Shareholders' Equity - Changes in Accumulated Other Comprehensive Income (Loss) Balances (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2017	$ (45,629)
Reclassification to the income statement	(9,645)
Change in fair value	(7,699)
Balance as of December 31, 2018	(62,973)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2017	(42,442)
Reclassification to the income statement	0
Change in fair value	(18,062)
Balance as of December 31, 2018	(60,504)
Cash Flow Hedging Derivatives
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2017	(34)
Reclassification to the income statement	(9,906)
Change in fair value	10,363
Balance as of December 31, 2018	423
Retirement Benefit Plan Activity
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance as of December 31, 2017	(3,153)
Reclassification to the income statement	261
Change in fair value	0
Balance as of December 31, 2018	$ (2,892)