Other Comprehensive Income (Loss) Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019		Jun. 30, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances	$ 640,510	$ 620,450	$ 565,780	$ 544,020	$ 620,450		$ 544,020
Total other comprehensive income (loss)	(1,530)	3,020	1,910	(1,480)	1,490		430
Balances	647,360	640,510	585,690	565,780	647,360		585,690
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax					(500)		500
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax					100		800
Defined Benefit Plans [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances		(7,200)		(10,450)	(7,200)		(10,450)
Net unrealized gains (losses) arising during the period					0		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax					(200)	[1]	(2,850)	[2]
Total other comprehensive income (loss)					200		2,850
Reclassification of stranded tax effects					(1,260)
Balances	(8,260)		(7,600)		(8,260)		(7,600)
Accumulated Net Gain (Loss) from Hedges Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances		940		(3,170)	940		(3,170)
Net unrealized gains (losses) arising during the period					1,490	[3]	1,670	[4]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax					0		0
Total other comprehensive income (loss)					1,490		1,670
Reclassification of stranded tax effects					(10)
Balances	2,420		(1,500)		2,420		(1,500)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances		(10,590)		(3,710)	(10,590)		(3,710)
Net unrealized gains (losses) arising during the period					(200)		(4,090)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax					0		0
Total other comprehensive income (loss)					(200)		(4,090)
Reclassification of stranded tax effects					0
Balances	(10,790)		(7,800)		(10,790)		(7,800)
Accumulated Other Comprehensive Income [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances	(15,100)	(16,850)	(18,810)	(17,330)	(16,850)		(17,330)
Net unrealized gains (losses) arising during the period					1,290		(2,420)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax					(200)		(2,850)
Total other comprehensive income (loss)	(1,530)	3,020	1,910	(1,480)	1,490		430
Reclassification of stranded tax effects					(1,270)
Balances	$ (16,630)	$ (15,100)	$ (16,900)	$ (18,810)	$ (16,630)		$ (16,900)

[1] Defined benefit plans, net of income tax of approximately $0.1 million. See Note 16, "Defined Benefit Plans," for further details.

[2] Defined benefit plans, net of income tax of approximately $0.8 million. See Note 16, "Defined Benefit Plans," for further details.

[3] Derivative instruments, net of income tax of approximately $0.5 million. See Note 10, "Derivative Instruments," for further details.

[4] Derivative instruments, net of income tax of approximately $0.5 million. See Note 10, "Derivative Instruments," for further details.