Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Restricted Stock Restricted Stock [Member] Share-based Compensation Arrangement by Share-based Payment Award Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Non-vested restricted stock outstanding, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeitures, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Non-vested restricted stock outstanding, ending balance Non-vested restricted stock outstanding, weighted average grant date fair value, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted, weighted average grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Vested, weighted average grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeitures, weighted average grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Non-vested restricted stock outstanding, weighted average grant date fair value, ending balance Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] Schedule of Net Benefit Costs Schedule of Net Benefit Costs [Table Text Block] Schedule of Assumptions Used Schedule of Assumptions Used [Table Text Block] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Domain] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Pension Plan Pension Plan [Member] Postretirement Health Plan Other Postretirement Benefit Plan [Member] Defined Benefit Plans and Other Postretirement Benefit Plans Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on plan assets Defined Benefit Plan, Expected Return on Plan Assets Amortization of Prior service costs Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Amortization of Other actuarial loss Defined Benefit Plan, Amortization of Gains (Losses) Net periodic benefit cost Defined Benefit Plan, Net Periodic Benefit Cost Condensed Consolidated Balance Sheet Parenthetical [Abstract] Condensed Consolidated Balance Sheet Parenthetical [Abstract] Statement [Table] Statement [Table] Common Stock Common Stock [Member] Common Class B Common Class B [Member] Statement Statement [Line Items] Current Assets Assets, Current [Abstract] Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current Other Assets Other Assets, Noncurrent [Abstract] Accumulated amortization of trademarks and patents TrademarksAndPatentsAccumulated Amortization The accumulated amount of amortization of the costs pertaining to the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit PLUS the accumulated amount of amortization of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Accumulated amortization of customer lists Customer list accumulated amortization Accumulated amortization as of the balance sheet date that pertains to a customer list finite-lived intangible asset. Noncurrent Liabilities Liabilities, Noncurrent [Abstract] Net unamortized debt issuance costs Debt Issuance Costs, Noncurrent, Net Stockholder's Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares issued Common Stock, Shares, Issued Treasury stock, common shares Treasury Stock, Shares Inventory Disclosure [Abstract] Inventories Inventory, Policy [Policy Text Block] Accumulated Other Comprehensive Income [Abstract] Accumulated Other Comprehensive Income [Abstract] Accumulated Other Comprehensive (Loss) Income Comprehensive Income (Loss) Note [Text Block] Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entities [Table] Entities [Table] Entity Information Entity Information [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Related Party Transactions [Abstract] Related Party Transactions Disclosure Related Party Transactions Disclosure [Text Block] Inventories Inventory Disclosure [Text Block] Postretirement Health Plan Employer contributions Defined Benefit Plan, Contributions by Employer Estimated contributions in remainder of current fiscal year Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year Medical Cost Trend Assumption Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year Ultimate Health Care Cost Trend Rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Year that Rate Reaches Ultimate Trend Rate Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2006 Plan 2006 Plan [Member] 2006 Plan [Member] 2006 Plan - Director Stock Option Director Stock Option [Member] Stock options issued to company directors. 2006 Plan - Employee Stock Options 2006 Plan - Employee Stock Options [Member] Employee Stock Options under our 2006 Long Term Incentive Plan Stock Options Employee Stock Option [Member] Number Authorized (shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Award Vesting Period (Years) Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Annual Vesting Percentage ShareBasedCompensationVestingPercentageAnnual Percent of share based compensation that vests annually. Number of years after grant date vesting starts (years) NumberYearsAfterGrantDateVestingStarts The number of years after the grant date that vesting starts. Number of consecutive years vesting occurs after initial vest date (years) NumberOfConsecutiveYearsVestingOccursAfterInitialVestDate Number of consecutive years vesting continues after the initial vest date. Exercised, number of shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Cash Received from Exercise of Stock Options Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options Tax Benefit Realized from Exercise of Stock Options Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options Options, Granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Award Vesting Period, Minimum (years) ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPeriodMinimum Mininimum period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition Award Vesting Period, Maximum (years) ShareBasedCompensationArrangementByShareBasedPaymentAwardVestingPeriodMaximum Maximum period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition Share-based Compensation Expense Allocated Share-based Compensation Expense Condensed Consolidated Statements of Comprehensive Income [Abstract] Condensed Consolidated Statements of Comprehensive Income [Abstract] Statement, Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Net Income (Loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Other Comprehensive Income (Loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Pension and postretirement benefits (net of tax) Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax Cumulative translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Other Comprehensive Income Other Comprehensive Income (Loss), Net of Tax Total Comprehensive Income (Loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Summary of Stock Option Transactions Options outstanding, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Options exercisable, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Options outstanding, ending balance Options exercisable, ending balance Options outstanding, weighted average exercise price, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Options exercisable, weighted average exercise price, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Exercised, weighted average exercise price Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Options outstanding, weighted average exercise price, ending balance Options exercisable, weighted average exercise price, ending balance Options outstanding, weighted average remaining contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Options exercisable, weighted average remaining contractual term Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Options outstanding, aggregate intrinsic value, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Options exercisable, aggregate intrinsic value, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Exercised, aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Options outstanding, aggregate intrinsic value, ending balance Options exercisable, aggregate intrinsic value, ending balance Accumulated Other Comprehensive (Loss) Income by Component Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities [Abstract] Net Income Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Amortization and Accretion, Net Amortization of investment net discount Accretion (Amortization) of Discounts and Premiums, Investments Non-cash stock compensation expense Share-based Compensation Excess tax benefits for share-based payments Excess Tax Benefit from Share-based Compensation, Operating Activities Deferred income taxes Deferred Income Tax Expense (Benefit) Provision for bad debts and cash discounts Provision for Doubtful Accounts Loss on the sale of fixed assets Gain (Loss) on Disposition of Property Plant Equipment (Increase) Decrease in assets: Increase (Decrease) in Operating Assets [Abstract] Accounts receivable Increase (Decrease) in Accounts and Other Receivables Inventories Increase (Decrease) in Inventories Prepaid expenses Increase (Decrease) in Prepaid Expense and Other Assets Other assets Increase (Decrease) in Other Operating Assets Increase (Decrease) in liabilities: Increase (Decrease) in Operating Liabilities [Abstract] Accounts payable Increase (Decrease) in Accounts Payable and Income Taxes Payable The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business PLUS the increase (decrease) during the period in the amount due for taxes based on the reporting entity's earnings or attributable to the entity's income earning process (business presence) within a given jurisdiction. Accrued expenses Increase (Decrease) in Accrued Liabilities Deferred compensation Increase (Decrease) in Deferred Compensation Pension and postretirement benefits Increase (Decrease) in Pension and Postretirement Obligations Other liabilities Increase (Decrease) in Other Operating Liabilities Total Adjustments Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities Net Cash Provided by Operating Activities Net Cash Provided by (Used in) Operating Activities CASH FLOWS FROM INVESTING ACTIVITIES Net Cash Provided by (Used in) Investing Activities [Abstract] Capital expenditures Payments to Acquire Property, Plant, and Equipment Proceeds from sale of property, plant and equipment Proceeds from Sale of Property, Plant, and Equipment Purchases of short-term investments Payments to Acquire Short-term Investments Dispositions of short-term investments Proceeds from Sale of Short-term Investments Net Cash Used in Investing Activities Net Cash Provided by (Used in) Investing Activities CASH FLOWS FROM FINANCING ACTIVITIES Net Cash Provided by (Used in) Financing Activities [Abstract] Principal payments on notes payable Repayments of Senior Debt Dividends paid Payments of Ordinary Dividends, Common Stock Purchase of treasury stock Payments for Repurchase of Common Stock Proceeds from issuance of treasury stock Proceeds from Sale of Treasury Stock Proceeds from issuance of common stock Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Excess tax benefits for share-based payments Excess Tax Benefit from Share-based Compensation, Financing Activities Net Cash Used in Financing Activities Net Cash Provided by (Used in) Financing Activities Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Net Decrease in Cash and Cash Equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and Cash Equivalents, Beginning of Period Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents, End of Period Supplemental disclosure of non-cash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Capital expenditures accrued, but not paid Capital Expenditures Incurred but Not yet Paid Cash dividends declared and accrued, but not paid Dividends Payable Organization, Consolidation and Presentation of Financial Statements [Abstract] Basis of Statement Presentation Basis of Presentation and Significant Accounting Policies [Text Block] Amortization of intangible assets Amortization of Intangible Assets Amortization expense for remainder of current fiscal year Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year Indefinite-lived trademarks Indefinite-Lived Intangible Assets (Excluding Goodwill) Goodwill impairment loss Goodwill, Impairment Loss Segment Reporting [Abstract] Operating Segments Segment Reporting, Policy [Policy Text Block] Schedule of Stock Option Transactions Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Restricted Stock Transactions Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Fair Value Measurement, Policy Fair Value Measurement, Policy [Policy Text Block] Inventory, Current [Table] Inventory, Current [Table] Inventory [Axis] Inventory [Axis] Inventory [Domain] Inventory [Domain] Inventory Inventory [Line Items] Inventory obsolescence reserve Inventory Valuation Reserves Stock-based Compensation Policy Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Finished goods Inventory, Finished Goods, Gross Packaging Packaging Inventory Packaging Inventory Other Other Inventory, Gross Total Inventories Inventory, Net Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Business to Business Products Business to Business Segment [Member] Business to Business Segment [Member] Retail and Wholesale Products Retail and Wholesale Segment [Member] Retail and Wholesale Segment [Member] Unallocated Assets Segment Reconciling Items [Member] Segment Reporting Information Segment Reporting Information [Line Items] Assets Assets Segment Net Sales Revenues Total Sales Sales Revenue, Goods, Net Segment Income (Loss) Segment Reporting Information, Operating Income for Reportable Segment Segment Reporting Information, Operating Income for Reportable Segment Corporate Expenses Corporate Expenses The corporate expenses line represents certain unallocated expenses, including primarily salaries, wages and benefits, purchased services, rent, utilities and depreciation and amortization associated with corporate functions such as research and development, information systems, finance, legal, human resources and customer service. Corporate expenses also include the annual incentive plan bonus accrual. Income (Loss) from Operations Operating Income (Loss) Total Other Income (Expense), Net Nonoperating Income (Expense) Income (Loss) before Income Taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income Taxes Income Tax Expense (Benefit) Operating Segment Disclosure Segment Reporting Disclosure [Text Block] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Measurement [Domain] Fair Value Hierarchy [Domain] Fair Value, Inputs, Level 1 Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 Fair Value, Inputs, Level 2 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Cash Equivalents Cash Equivalents, at Carrying Value Notes Payable, Fair Value Long-term Debt, Fair Value Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Cash and cash equivalents Short-term investments Short-term Investments Accounts receivable, less allowance of $782 and $753 at April 30, 2017 and July 31, 2016, respectively Receivables, Net, Current Inventories Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Current Prepaid repairs expense Other Prepaid Expense, Current Prepaid expenses and other assets Prepaid Expense, Current Total Current Assets Assets, Current Property, Plant and Equipment Property, Plant and Equipment, Net [Abstract] Cost Property, Plant and Equipment, Gross Less accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Total Property, Plant and Equipment, Net Property, Plant and Equipment, Net Goodwill Goodwill Trademarks and patents, net of accumulated amortization of $287 and $261 at April 30, 2017 and July 31, 2016, respectively Trademarks and patents, net The total amount, net of amortization, as of the balance sheet date for 1) the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit and 2) costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Customer list, net of accumulated amortization of $4,315 and $3,460 at April 30, 2017 and July 31, 2016, respectively Customer list, net Gross carrying amount before accumulated amortization as of the balance sheet date of an asset comprised of customer information, acquired in a business combination or other transaction, having a finite beneficial life. Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Other Other Assets, Noncurrent Total Other Assets Assets, Noncurrent Total Assets LIABILITIES & STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current Liabilities Liabilities, Current [Abstract] Current maturities of notes payable Senior Notes, Current Accounts payable Accounts Payable and Accrued Liabilities, Current Dividends payable Dividends Payable, Current Accrued expenses: Accrued Liabilities, Current [Abstract] Salaries, wages and commissions Employee-related Liabilities, Current Trade promotions and advertising Accrued Marketing Costs, Current Freight Accrued Liabilities, Current Other Other Liabilities, Current Total Current Liabilities Liabilities, Current Notes payable, net of unamortized debt issuance costs of $96 and $118 at April 30, 2017 and July 31, 2016, respectively Senior Notes, Noncurrent Deferred compensation Deferred Compensation Liability, Classified, Noncurrent Pension and postretirement benefits Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent Other Other Liabilities, Noncurrent Total Noncurrent Liabilities Liabilities, Noncurrent Total Liabilities Liabilities Stockholders’ Equity Common Stock, Value, Issued Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss: Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Pension and postretirement benefits Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax Cumulative translation adjustment Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Total accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Less Treasury Stock, at cost (2,907,370 Common and 324,741 Class B shares at April 30, 2017 and 2,912,953 Common and 324,741 Class B shares at July 31, 2016) Treasury Stock, Value Total Stockholders' Equity Stockholders' Equity Attributable to Parent Total Liabilities & Stockholders’ Equity Liabilities and Equity Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Total Accumulated Other Comprehensive (Loss) Income Equity Component [Domain] Pension and Postretirement Health Benefits Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Cumulative Translation Adjustment Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive (Loss) Income, Balance, beginning Other comprehensive income before reclassifications, net of tax Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Amounts reclassified from accumulated other comprehensive income, net of tax Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Net current-period other comprehensive income, net of tax Accumulated Other Comprehensive (Loss) Income, Balance, ending Operating Segments Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] NEW ACCOUNTING PRONOUNCEMENTS [Abstract] NEW ACCOUNTING PRONOUNCEMENTS [Abstract] New Accounting Pronouncements New Accounting Pronouncements [Text Block] Disclosure of new accounting pronouncements adopted during the period or new accounting pronouncements that have been issued but not yet adopted. Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Future Amortization Expense Finite-Lived Intangible Assets [Line Items] 2018 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2019 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Five Discount rate for net periodic benefit cost Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Rate of increase in compensation levels Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Long-term expected rate of return on assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets Disclosure of Compensation Related Costs, Share-based Payments Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Number of Reportable Segments Number of Reportable Segments Accounting Changes and Error Corrections [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Axis] Adjustments for Change in Accounting Principle [Domain] Adjustments for Change in Accounting Principle [Domain] New Accounting Pronouncements or Change in Accounting Principle New Accounting Pronouncements or Change in Accounting Principle [Line Items] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Selling, General and Administrative Expenses Selling, General and Administrative Expenses, Policy [Policy Text Block] Trade Receivable Trade and Other Accounts Receivable, Policy [Policy Text Block] Overburden Removal and Mining Costs Overburden Removal and Mining Costs [Policy Text Block] Description of accounting policy for overburden removal/stripping costs for mined properties and other mining-related costs. Reclamation Asset Retirement Obligations, Policy [Policy Text Block] Equity Component [Domain] Tax for reclassification adjustment from AOCI for pension and other postretirement benefits Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Tax Pension and Other Postretirement Benefits Disclosure Pension and Other Postretirement Benefits Disclosure [Text Block] Condensed Consolidated Statements of Income and Retained Earnings [Abstract] Condensed Consolidated Statements of Income and Retained Earnings [Abstract] Net Sales Cost of Sales Cost of Goods Sold Gross Profit Gross Profit Selling, General and Administrative Expenses Selling, General and Administrative Expense Income (Loss) from Operations Other Income (Expense) Nonoperating Income (Expense) [Abstract] Interest expense Interest Expense, Debt Interest income Investment Income, Interest Other, net Other Nonoperating Income (Expense) Total Other Income (Expense), Net Income (Loss) Before Income Taxes Income Tax (Expense) Benefit Net Income (Loss) Retained Earnings: Retained Earnings (Accumulated Deficit) [Abstract] Balance at beginning of period Cash dividends declared and treasury stock issuances Cash dividends declared and treasury stock issuances Common stock cash dividend declared by an entity during the period plus the value of treasury stock reissued during the period.. This element includes paid and unpaid dividends declared during the period. Balance at End of Period Net Income Per Share Earnings Per Share [Abstract] Basic Common (in dollars per share) Earnings Per Share, Basic Diluted Common (in dollars per share) Earnings Per Share, Diluted Average Shares Outstanding Weighted Average Shares Outstanding [Abstract] Weighted Average Shares Outstanding [Abstract] Basic Common (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted Common (in shares) Weighted Average Number of Shares Outstanding, Diluted Dividends Declared Per Share (in dollars per share) Common Stock, Dividends, Per Share, Declared Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Director [Member] Director [Member] Related Party Transaction Related Party Transaction [Line Items] Revenue from Related Parties Revenue from Related Parties Accounts Receivable, Related Parties, Current Accounts Receivable, Related Parties, Current Inventories Schedule of Inventory, Current [Table Text Block]