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Valuation and Qualifying Accounts (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Receivables aging period | 60 days |
Accounts receivable reserve period | 90 days |
Allowance for doubtful accounts | $ 3,484 | $ 2,853
Reserves for sales discounts | 15,094 | 15,999
Inventory obsolescence reserves | $ 9,675 | 7,601
Inventory usage period | 3 years |
Inventory reserve percentage | 100.00% |
Product warranty accrual period of expenses used in calculation | 12 months |
Product warranty accrual period for sales used in calculation | 12 months |
Warranty | $ 5,566 | $ 5,913
Wholegood Units |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Product warranty period | 1 year |
Parts |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Product warranty period | 90 days |
Minimum |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Sales discount percentage of customers who qualify for each program that discount available | 90.00% |
Product warranty accrual lag period | 90 days |
Maximum |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Sales discount percentage of customers who qualify for each program that discount available | 95.00% |
Product warranty accrual lag period | 6 months |

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