Detail of Certain Balance Sheet Accounts - Changes in Accumulated Other Comprehensive Loss (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ 490,237,000	$ 392,992,000
Other comprehensive income (loss) before reclassifications			60,546,000	21,957,000
Amounts reclassified from accumulated other comprehensive income (loss)			879,000	0
Other comprehensive income, net of tax	$ 19,591,000	$ 3,946,000	61,425,000	21,957,000
Ending balance	584,368,000	534,728,000	584,368,000	534,728,000
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(158,530,000)	(138,568,000)
Ending balance	(97,105,000)	(116,611,000)	(97,105,000)	(116,611,000)
Cumulative Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(72,731,000)	(65,995,000)
Other comprehensive income (loss) before reclassifications			60,691,000	27,311,000
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Other comprehensive income, net of tax			60,691,000	27,311,000
Ending balance	(12,040,000)	(38,684,000)	(12,040,000)	(38,684,000)
Net Unrealized Gain (Loss) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			515,000	0
Other comprehensive income (loss) before reclassifications			(145,000)	(5,354,000)
Amounts reclassified from accumulated other comprehensive income (loss)			879,000	0
Other comprehensive income, net of tax			734,000	(5,354,000)
Ending balance	1,249,000	(5,354,000)	1,249,000	(5,354,000)
Net Unrealized Loss on Net Investment Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(1,926,000)	(1,926,000)
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Other comprehensive income, net of tax			0	0
Ending balance	(1,926,000)	(1,926,000)	(1,926,000)	(1,926,000)
Benefit Plans Liability, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(84,388,000)	(70,647,000)
Other comprehensive income (loss) before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Other comprehensive income, net of tax			0	0
Ending balance	$ (84,388,000)	$ (70,647,000)	$ (84,388,000)	$ (70,647,000)