Shareholders' Equity Changes in Accumulated Other Comprehensive Income (Loss) Balances (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2015			$ (62,492)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax			2,266
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	$ 1,528	$ (5,072)	490	$ (32,763)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax			(6,397)
Balance as of September 30, 2016	(66,623)		(66,623)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2015			(64,360)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax			490
Balance as of September 30, 2016	(63,870)		(63,870)
Cash Flow Hedging | Foreign Exchange Contract
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2015			1,868
Reclassification to the income statement			2,266
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax			(6,887)
Balance as of September 30, 2016	$ (2,753)		$ (2,753)