Shareholders' Equity - Components of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 335,397	$ 296,608	$ 263,477
Other comprehensive income (loss)	(3,246)	(53)
Income taxes	642	(438)
Interest income (expense), net	(122)	(828)	(416)
Other expense, net	(8,143)	(6,381)	(4,004)
Income taxes	1,413	9,074	29,100
Ending Balance	327,631	335,397	296,608
Reclassification Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Interest income (expense), net	(1,034)
Other expense, net	(5,193)
Income taxes	1,559
ASU 2018-02 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Cumulative effect adjustment from adoption of ASU 2018-02	937
Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(2,386)	(563)
Other comprehensive income (loss)	(653)	(1,823)
Ending Balance	(3,039)	(2,386)	(563)
Debt Security [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	5,682	4,350
Other comprehensive income (loss)	(2,593)	1,770
Income taxes	642	(438)
Ending Balance		5,682	4,350
Debt Security [Member] | Reclassification Adjustments [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Interest income (expense), net	(1,034)
Other expense, net	(5,193)
Income taxes	1,559
Debt Security [Member] | ASU 2018-02 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Cumulative effect adjustment from adoption of ASU 2018-02	937
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	3,296	3,787	(6,580)
Ending Balance	(3,039)	$ 3,296	$ 3,787
Accumulated Other Comprehensive Income (Loss) [Member] | ASU 2018-02 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Cumulative effect adjustment from adoption of ASU 2018-02	$ 937