Change in Accumulated Other Comprehensive Income (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31, 2015	$ 122,748
Other comprehensive income	(618)
Balance at June 30, 2016	163,724
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31, 2015	(8,566)
Balance at June 30, 2016	(9,184)
Accumulated Net Unrealized Investment Gain (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31, 2015	(11)
Other comprehensive income	15
Balance at June 30, 2016	4
Accumulated Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31, 2015	(8,555)
Other comprehensive income	(633)
Balance at June 30, 2016	$ (9,188)