Taxes Computed at Statutory Federal Income Tax Rate Reconciled to Provision for Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Loss From Operations Before Provision Benefit For Income Taxes [Line Items]
United States federal tax at statutory rate									$ (4,714)	$ 200	$ (23,844)
Non-deductible acquisition and reorganization expenses									1,400	(2)	(56)
Research credits									(3,360)	(3,000)	(3,133)
Change in unrecognized tax benefits									(545)	(208)	(519)
State income taxes, net of federal benefit									(371)	182	(2,120)
Compensation									651	765	1,017
Meals and entertainment									1,341	1,023	954
Impact of foreign operations									2,847	1,848	2,505
Provision-to-Return adjustments									(1,116)	(136)	0
Settlements with taxing authorities									0	(4,218)	0
Deemed Dividends									887	1,408	0
Dividends Accrued									2,198	1,190	0
Federal, state and local rate changes									344	1,104	(268)
Non-deductible items									70	(5)	82
Valuation allowance									(17,504)	1,816	24,666
Other									58	135	(749)
Income tax provision (benefit)	$ (15,218)	$ (2,656)	$ (503)	$ 563	$ (1,557)	$ 3,692	$ 1,472	$ (981)	(17,814)	2,626	(1,664)
Bilateral Advance Pricing Agreement [Member]
Income Loss From Operations Before Provision Benefit For Income Taxes [Line Items]
Bilateral Advance Pricing Agreement impact									$ 0	$ 524	$ (199)