Other Comprehensive Income (Loss )- Components of Accumulated Other Comprehensive Loss, Net of Tax (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Equity [Abstract]
Foreign Currency Translation Adjustments, Beginning balance			$ (566)
Foreign currency translation adjustments, net of tax	$ 104	$ (359)	(675)	$ (43)
Foreign Currency Translation Adjustments, Ending balance	(1,241)		(1,241)
Net Unrealized Gain (Loss) on Investment, Beginning balance			15,882
Unrealized gain (loss) on investment, net of tax	(5,678)	3,915	(5,936)	6,572
Net Unrealized Gain (Loss) on Investment, Ending balance	9,946		9,946
Net Unrealized Losses on Derivatives, Beginning balance			(380)
Unrealized loss on cash flow hedging instruments, net of tax	(1,705)	(612)	(3,390)	(849)
Net Unrealized Losses on Derivatives, Ending balance	(3,770)		(3,770)
Accumulated Other Comprehensive Income (Loss), Beginning balance			14,936
Accumulated Other Comprehensive (Income) Loss, Current period change	(7,279)	$ 2,944	(10,001)	$ 5,680
Accumulated Other Comprehensive Income (Loss), Ending balance	$ 4,935		$ 4,935