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Valuation and Qualifying Accounts - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Inventory obsolescence reserves | $ 12,000 | $ 8,200 |  |
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 | $ 9,096 | 10,249 |  |
Parts |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Product warranty period | 90 days |  |  |
Minimum |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Product warranty accrual lag period | 90 days |  |  |
Maximum |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Product warranty accrual lag period | 6 months |  |  |
Maximum | Wholegoods |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Product warranty period | 1 year |  |  |
Reserve for sales discounts |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Reserves for sales discounts on products shipped under promotional programs | $ 13,549 | $ 16,883 | $ 18,123 | $ 15,652

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