Other Comprehensive Income (Loss) Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021		Sep. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances	$ 597,600	$ 595,970	$ 584,250	$ 661,100	$ 675,460	$ 697,480	$ 584,250		$ 697,480
Total other comprehensive income (loss)	(510)	990	630	1,320	(660)	(3,680)	1,110		(3,020)
Balances	614,320	597,600	595,970	557,970	661,100	675,460	614,320		557,970
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax							100		100
Cross Currency Interest Rate Contract [Member]
Other Comprehensive Income (Loss), Tax [Abstract]
Other Comprehensive Income (Loss), Tax							(2,400)		700
Defined Benefit Plans [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances			(8,620)			(9,930)	(8,620)		(9,930)
Net unrealized gains (losses) arising during the period							0		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							(470)	[1]	(470)	[2]
Total other comprehensive income (loss)							470		470
Balances	(8,150)			(9,460)			(8,150)		(9,460)
Accumulated Net Gain (Loss) from Hedges Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances			(3,580)			4,230	(3,580)		4,230
Net unrealized gains (losses) arising during the period							7,210	[3]	(2,280)	[4]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							0		0
Total other comprehensive income (loss)							7,210		(2,280)
Balances	3,630			1,950			3,630		1,950
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances			6,580			(300)	6,580		(300)
Net unrealized gains (losses) arising during the period							(6,570)		(1,210)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							0		0
Total other comprehensive income (loss)							(6,570)		(1,210)
Balances	10			(1,510)			10		(1,510)
Accumulated Other Comprehensive Income [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balances	(4,000)	(4,990)	(5,620)	(10,340)	(9,680)	(6,000)	(5,620)		(6,000)
Net unrealized gains (losses) arising during the period							640		(3,490)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							(470)		(470)
Total other comprehensive income (loss)	(510)	990	630	1,320	(660)	(3,680)	1,110		(3,020)
Balances	$ (4,510)	$ (4,000)	$ (4,990)	$ (9,020)	$ (10,340)	$ (9,680)	$ (4,510)		$ (9,020)

[1] Defined benefit plans, net of income tax of approximately $0.1 million. See Note 17, "Defined Benefit Plans," for further details.

[2] Defined benefit plans, net of income tax of approximately $0.1 million. See Note 17, "Defined Benefit Plans," for further details.

[3] Derivative instruments, net of income tax of approximately $2.4 million. See Note 10, "Derivative Instruments," for further details

[4] Derivative instruments, net of income tax of approximately $0.7 million. See Note 10, "Derivative Instruments," for further details.