Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Trading Symbol Trading Symbol Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Statement Of Financial Position [Abstract] Statement of Financial Position [Abstract] Assets [Abstract] ASSETS Assets: Cash and Cash Equivalents Cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Available-For-Sale Securities, Debt Securities, Current Marketable securities Accounts Receivable, Net, Current Accounts receivable, net of allowance for doubtful accounts of $25 in 2018 and $25 in 2017 Net accounts receivable Inventory, Net, Total Inventories Total inventories Income Taxes Receivable, Current Income taxes receivable Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets Current Assets Total current assets Total current assets Property, Plant and Equipment, Net, Total Property, plant and equipment, net of accumulated depreciation of $24,813 in 2018 and $24,395 in 2017 Net property, plant and equipment Goodwill Goodwill Other Intangibles, Net Other intangibles, net Available-For-Sale Securities, Debt Securities, Noncurrent Marketable securities Deferred Tax Assets, Net, Noncurrent Deferred income taxes Other Assets Other assets Total Assets Total assets Total assets Liabilities and Stockholders Equity LIABILITIES AND STOCKHOLDERS' EQUITY Accounts Payable, Current Accounts payable Accrued Expenses and Other Current Liabilities Accrued expenses and other liabilities Total accrued expenses and other liabilities Total accrued expenses and other liabilities Represents carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Liabilities, Current Total current liabilities Total current liabilities Defined Benefit Pension Plan, Liabilities, Noncurrent Pension liabilities Pension liabilities Pension liabilities Other Liabilities, Noncurrent Other long-term liabilities Total Liabilities Total liabilities Total liabilities Common Stock, Value, Issued Common stock Additional Paid in Capital, Common Stock Capital in excess of par value Retained Earnings (Accumulated Deficit) Retained earnings Accumulated Other Comprehensive Income (Loss), Net Of Tax Accumulated other comprehensive loss Balance Balance Total Stockholders Equity Total stockholders' equity Total stockholders' equity Balance Balance Total Liabilities and Stockholders Equity Total liabilities and stockholders' equity Total liabilities and stockholders' equity Allowance for Doubtful Accounts Receivable, Current Allowance for doubtful accounts Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accumulated depreciation Income Statement Income Statement Revenue, Net Net sales from all dealers Net sales Cost of Goods and Services Sold, Total Cost of goods sold Gross Profit Gross profit Gross profit Selling, General and Administrative Expense Selling, general and administrative expenses related to employment agreements Selling, general and administrative expenses Operating Income (Loss) Operating income Operating income Interest Income Interest income Income (Loss) From Continuing Operations Before Income Taxes, Extraordinary Items, Noncontrolling Interest Income before income taxes Income before income taxes Income Tax Expense (Benefit) Income tax provision Total income tax provision Net Income (Loss) Attributable To Parent Net income available for stockholders: Net income Net (loss) income Net income EARNINGS PER SHARE Earnings per share Basic Earnings per share (in dollars per share) Basic earnings per share (in dollars per share) Basic (in dollars per shares) Basic earnings per share, Total (in dollars per share) Earnings Per Share, Diluted Diluted earnings per share (in dollars per share) Diluted (in dollars per shares) Diluted earnings per share, Total (in dollars per share) Dividends Paid Per Share Dividends paid per share (in dollars per share) Statement Of Income and Comprehensive Income Statement Of Income and Comprehensive Income Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Other comprehensive income, net of taxes: Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net Of Tax Pension adjustment Total activity in period Pension adjustment Pension adjustment, net of taxes Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Total Unrealized gain on debt securities, net of reclassification adjustments Total activity in period Unrealized gain on securities, net of taxes and reclassification adjustment Comprehensive Income (Loss), Net Of Tax, Attributable To Parent, Total Comprehensive income Comprehensive income Statement Of Stockholders Equity Statement Of Stockholders Equity Statement [Table] Statement [Table] Equity Components [Axis] Statement, Equity Components [Axis] Common Stock [Member] Common stock Common Stock Additional Paid-In Capital [Member] Capital in Excess of Par Value Retained Earnings [Member] Retained Earnings Accumulated Other Comprehensive Income (Loss) [Member] Accumulated Other Comprehensive Income (Loss) Equity Component [Domain] Equity Component [Domain] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common Stock, Shares, Outstanding Common stock, shares outstanding Balance (in shares) Balance (in shares) Balance (in shares) Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures, Total Stock issued for stock incentive plans, net Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures, Total Stock issued for stock incentive plans, net (in shares) Stock Repurchased and Retired During Period, Value Stock purchased and retired Stock purchased and retired Stock Repurchased and Retired During Period, Shares Stock purchased and retired (in shares) Stock purchased and retired (in shares) Dividends, Common Stock, Cash Dividends declared Dividends paid Statement Of Cash Flows Statement Of Cash Flows Net Cash Provided By (Used In) Operating Activities, Continuing Operations [Abstract] OPERATING ACTIVITIES Adjustments To Reconcile Net Income (Loss) To Net Cash Provided By (Used For) Operating Activities Adjustments to reconcile net income to net cash provided by operating activities: Depreciation, Depletion and Amortization Depreciation and amortization Gain (Loss) On Sale Of Property Plant Equipment Gain on sale of equipment and property Gain on sale of equipment and property Amortization Of Premium Related To Marketable Securities Amortization of premium related to marketable securities Represent amount of amortization of premium related to marketable securities. Stock-Based Compensation Expense Stock-based compensation expense Deferred Income Tax Benefit Deferred income tax provision (Increase) Decrease In Assets (Increase) decrease in assets: Increase (Decrease) In Accounts Receivable Accounts receivable Accounts receivable Increase (Decrease) In Inventories Inventories Inventories Increase (Decrease) In Prepaid Expense and Other Assets Prepaid expenses and other current assets Prepaid expenses and other current assets Increase (Decrease) In Income Taxes Receivable Income taxes receivable Income taxes receivable Other Non-Current Assets Other non-current assets Other non-current assets Increase (Decrease) In Liabilities Increase (decrease) in liabilities: Increase (Decrease) In Accounts Payable Accounts payable Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Accrued expenses and other liabilities Increase (Decrease) In Other Noncurrent Liabilities Other long-term liabilities Net Cash Provided By (Used In) Operating Activities, Continuing Operations Net cash provided by operating activities Net cash provided by operating activities Net Cash Provided By (Used In) Investing Activities, Continuing Operations [Abstract] INVESTING ACTIVITIES Capital Expenditures Capital expenditures Capital expenditures Proceeds From Sale Of Productive Assets Proceeds from sale of assets Purchases Of Marketable Securities Purchases of marketable securities Purchases of marketable securities Proceeds From Sale Of Marketable Securities Sales of marketable securities The cash inflow associated with the aggregate amount received by the entity through sale of marketable securities (held-to-maturity or available-for-sale) during the period. Proceeds From Maturity Of Marketable Securities Maturities of marketable securities The cash inflow associated with the aggregate amount received by the entity through maturity of marketable securities (held-to-maturity or available-for-sale) during the period. Net Cash Provided By (Used In) Investing Activities, Continuing Operations Net cash provided by (used for) investing activities Net cash provided by (used for) investing activities Net Cash Provided By (Used In) Financing Activities, Continuing Operations [Abstract] FINANCING ACTIVITIES Payment Of Dividends Payment of dividends Payment of dividends Cash Paid For Common Stock Purchased and Retired Cash paid for common stock purchased and retired Cash paid for common stock purchased and retired Net Cash Provided By (Used In) Financing Activities, Continuing Operations Net cash used for financing activities Net cash used for financing activities Net (Decrease) Increase In Cash and Cash Equivalents Net increase (decrease) in cash and cash equivalents Net increase in cash and cash equivalents Supplemental Cash Flow Information [Abstract] Supplemental information: Income Taxes Paid, Net Total net income tax payments Income tax payments, net General [Abstract] General Organization, Consolidation and Presentation Of Financial Statements Disclosure [Text Block] GENERAL RECENT ACCOUNTING STANDARDS RECENT ACCOUNTING PRONOUNCEMENTS Accounting Changes and Error Corrections [Text Block] RECENT ACCOUNTING STANDARDS NET SALES Revenue from Contract with Customer [Text Block] NET SALES Earnings Per Share [Text Block] EARNINGS PER SHARE STOCK-BASED COMPENSATION STOCK-BASED COMPENSATION Disclosure Of Compensation Related Costs, Share-Based Payments [Text Block] STOCK-BASED COMPENSATION MARKETABLE SECURITIES Available-for-sale securities Investments In Debt and Marketable Equity Securities (And Certain Trading Assets) Disclosure [Text Block] MARKETABLE SECURITIES WARRANTY COSTS AND OTHER CONTINGENCIES WARRANTY COSTS AND OTHER CONTINGENCIES Product Warranty Disclosure [Text Block] WARRANTY COSTS AND OTHER CONTINGENCIES BUSINESS SEGMENT INFORMATION BUSINESS SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] BUSINESS SEGMENT INFORMATION INVENTORIES Inventory Disclosure [Abstract] Inventory Disclosure [Text Block] INVENTORIES INCOME TAXES Income Tax Disclosure [Abstract] Income Taxes INCOME TAXES EMPLOYEE BENEFIT PLANS Employee Benefit Plans Compensation and Retirement Disclosure [Abstract] Employee Benefit Plans EMPLOYEE BENEFIT PLANS FAIR VALUE MEASUREMENTS Fair Value Disclosures [Abstract] Fair Value Measurements FAIR VALUE MEASUREMENTS ACCUMULATED OTHER COMPREHENSIVE LOSS Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Loss Income [Text Block] ACCUMULATED OTHER COMPREHENSIVE LOSS The entire disclosure of accumulated other comprehensive (loss) income. SUBSEQUENT EVENT SUBSEQUENT EVENT Subsequent Events [Text Block] SUBSEQUENT EVENT Accounting Policies [Abstract] New Accounting Pronouncements, Policy [Policy Text Block] RECENT ACCOUNTING STANDARDS Disaggregation of Revenue [Table Text Block] Schedule of disaggregation of revenues Contract with Customer, Asset and Liability [Table Text Block] Schedule of contract balances Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of reconciliation of weighted average shares outstanding Schedule Of Employee Service Share-Based Compensation, Allocation Of Recognized Period Costs [Table Text Block] Schedule of stock-based compensation Schedule Of Nonvested Restricted Stock Units Activity [Table Text Block] Schedule of the changes in non-vested restricted shares Schedule Of Net Realized Gain Loss and Reclassification Table [Text Block] Schedule of net realized gains and reclassification of net realized gains from other comprehensive income Tabular disclosure of net realized gains and the reclassification of net realized gains from other comprehensive income. Marketable Securities [Table Text Block] Schedule of gross unrealized gains (losses) on marketable securities Available-For-Sale Securities [Table Text Block] Schedule of amortized cost basis, fair value and net unrealized gains on available-for-sale securities Schedule Of Product Warranty Liability [Table Text Block] Schedule of analysis of warranty accruals Schedule Of Inventory, Current [Table Text Block] Schedule of inventories Schedule Of Net Benefit Costs [Table Text Block] Schedule of net periodic benefit cost (credit) and related components for the plan Fair Value, Assets Measured On Recurring Basis [Table Text Block] Schedule of the valuation of financial instruments measured at fair value on a recurring basis Schedule Of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Schedule of accumulated other comprehensive loss Disaggregation of Revenue [Table] Products and Services [Axis] Products and Services [Domain] Boats And Accessories [Member] Boats And Accessories This member represents information about boats and accessories. Parts [Member] Parts This member represents information about parts. Disaggregation of Revenue [Line Items] Revenue from Contract with Customer, Including Assessed Tax Net sales Geographical [Axis] Geographical [Domain] Domestic [Member] Domestic This member represents information about revenue received from domestic. International [Member] International This member represents information about international. Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Domain] Transferred at Point in Time [Member] Products transferred at a point in time Transferred over Time [Member] Products transferred over time Balance Sheet Location [Axis] Balance Sheet Location [Domain] Accrued Expenses And Other Current Liabilities [Member] Accrued expenses and other current liabilities This member stands for accrued expenses and other current liabilities. Deferred Revenue, Current Deferred current revenue Revenue, Performance Obligation, Description of Payment Terms Revenue, Description of payment terms Distributed Earnings Less: Adjustments for earnings attributable to participating securities Less: Adjustments for earnings attributable to participating securities Net Income (Loss) Available to Common Stockholders, Basic Net Income in calculating earnings per share Net income used in calculating earnings per share Weighted Average Number Of Shares Including Participating Securities Outstanding Diluted Weighted average shares outstanding (including participating securities) Weighted number of shares including participating securities. Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights Adjustment for participating securities Adjustment for participating securities Weighted Average Number of Shares Outstanding, Basic and Diluted Weighted average shares outstanding (including participating securities) Basic (in shares) Shares used in calculating basic and diluted earnings per share (in shares) Shares used in calculating basic and diluted earnings per share Allocated Share-Based Compensation Expense Pre - tax cost Allocated Share-Based Compensation Expense, Net Of Tax After tax stock-based employee compensation expense After tax cost Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Defined Benefit Plans Disclosures [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Restricted shares of common stock Restricted Shares Restricted Stock Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Nonvested, Number Of Shares [Roll Forward] Shares Non-Vested Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Non-vested shares at December 31, 2017 Non-vested shares at March 31, 2018 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Vested Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Forfeited Forfeited Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward] Weighted Average Grant-Date Fair Value Non-Vested Shares At December 31, 2011 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Non-vested shares at December 31, 2017 Non-vested shares at March 31, 2018 Granted Granted Vested Vested Forfeited Forfeited