Stockholders' Equity Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended							9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019		Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019		Sep. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (14,674)	$ (17,881)	$ (16,945)	[1]	$ (17,230)	$ 2,254	$ (14,959)	$ (16,945)	[1]	$ (14,959)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(7,734)	3,351	(818)		(4,086)	(19,286)	17,392
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(174)	(144)	(118)		(145)	(198)	(179)
Other Comprehensive (loss) income, net of Tax	(7,908)	3,207	(936)		(4,231)	(19,484)	17,213	(5,637)		(6,502)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(22,582)	(14,674)	(17,881)		(21,461)	(17,230)	2,254	(22,582)		(21,461)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(16,436)	(19,274)	(17,682)		(16,868)	819	(14,578)	(17,682)		(14,578)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(7,533)	2,838	(1,592)		(5,415)	(17,687)	15,397
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0	0			0	0
Other Comprehensive (loss) income, net of Tax	(7,533)	2,838	(1,592)		(5,415)	(17,687)	15,397
Accumulated Other Comprehensive Income (Loss), Net of Tax	(23,969)	(16,436)	(19,274)		(22,283)	(16,868)	819	(23,969)		(22,283)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	1,657	1,288	638		(351)	1,449	(365)	638		(365)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(201)	513	768		1,323	(1,602)	1,993
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	(174)	(144)	(118)		(145)	(198)	(179)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(375)	369	650		1,178	(1,800)	1,814
Accumulated Other Comprehensive Income (Loss), Net of Tax	1,282	1,657	1,288		827	(351)	1,449	1,282		827
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax	105	105	99		(11)	(14)	(16)	99		(16)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0	0	6		6	3	2
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax	0	0	0			0	0
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0	0	6		6	3	2
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ 105	$ 105	$ 105		$ (5)	$ (11)	$ (14)	$ 105		$ (5)

[1] December 31, 2018 balances were derived from audited consolidated financial statements.