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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 |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | $ 851 | $ 973 | $ 1,391
Charged to Costs and Expenses | 969 | 1,005 | 1,239
Charged to Other Accounts | (8) | (121) | 51
Deductions from Reserves | (619) | (1,006) | (1,708)
Balance at End of Period | 1,193 | 851 | 973
Allowance for Deferred Income Tax Assets |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 9,977 | 27,578 | 19,304
Charged to Costs and Expenses | 19,277 |  | 6,700
Charged to Other Accounts | (491) | (14,009) | 1,574
Deductions from Reserves |  | (3,592) |
Balance at End of Period | 28,763 | 9,977 | 27,578
Reserve for Inventory |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 6,270 | 7,887 | 4,790
Charged to Costs and Expenses | 1,679 | 2,712 | 3,521
Charged to Other Accounts | (56) | (1,047) | 302
Deductions from Reserves | (1,820) | (3,282) | (726)
Balance at End of Period | $ 6,073 | $ 6,270 | $ 7,887

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- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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