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Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Allowance for Doubtful Accounts [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of period | $ 128 |  |
Charged to costs & expenses | 38 | $ 128 |
Deductions | 128 |  |
Balance at end of period | 38 | 128 |
Inventory Reserve [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of period | 30,009 | 23,355 | $ 25,249
Charged to costs & expenses | 5,893 | 7,006 | 6,406
Deductions | 1,740 | 352 | 8,300
Balance at end of period | 34,162 | 30,009 | 23,355
Warranty Liability [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of period | 8,623 | 9,724 | 8,548
Charged to costs & expenses | 4,569 | 7,392 | 6,951
Deductions | 4,798 | 8,493 | 5,775
Balance at end of period | 8,394 | 8,623 | 9,724
Deferred Tax Asset Valuation Allowance [Member] |  |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of period | 5,816 | 6,006 | 6,149
Charged to costs & expenses | 43,560 |  | 18
Deductions | 760 | 190 | 161
Balance at end of period | $ 48,616 | $ 5,816 | $ 6,006

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