Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowances for Accounts Receivable
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 4,045	$ 1,425	$ 1,651
Charged to Operations	4,034	2,414	1,016
Write-Offs	(5,149)	(923)	(1,257)
Recoveries	315	1,129	15
Other Changes	0	0	0
Balance at End of Period	3,245	4,045	1,425
Valuation Allowance for Deferred Tax Assets
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	55,336	63,616	52,001
Charged to Operations	(8,894)	(7,518)	12,038
Write-Offs	0	0	0
Recoveries	0	0	0
Other Changes	12	(762)	(423)
Balance at End of Period	$ 46,454	$ 55,336	$ 63,616