Annual report pursuant to Section 13 and 15(d)

Consolidated Valuation and Qualifying Accounts and Reserves (Detail)

v3.10.0.1
Consolidated Valuation and Qualifying Accounts and Reserves (Detail) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Allowance for doubtful accounts      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year $ 802 $ 1,209 $ 1,765
Charges (Reversals) to Cost or Expenses 469 (401) (438)
Deductions (421) (6) (118)
Balance at End of Year 850 802 1,209
Allowance for sales returns      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year 210 210 210
Balance at End of Year 210 210 210
Allowance for tax valuation      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year 40,866 54,310 49,514
Charges (Reversals) to Cost or Expenses 6,101 (13,444) 4,796
Balance at End of Year $ 46,967 $ 40,866 $ 54,310