Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		$ 1,182,551	$ 1,113,862	$ 1,160,660	$ 1,195,655
Other comprehensive income (loss)		(623)	1,404	10,239	(19,014)
Ending Balance		1,224,964	1,132,083	1,224,964	1,132,083
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		(1,214)	(27,649)	(12,076)	(7,231)
Ending Balance		(1,837)	(26,245)	(1,837)	(26,245)
Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		6,963	(5,574)	5,739	1,065
Other comprehensive income (loss) before reclassifications		1,469	3,249	2,693	(3,390)
Other Comprehensive Income (Loss), Tax		0	0	0	0
Other comprehensive income (loss)		1,469	3,249	2,693	(3,390)
Ending Balance		8,432	(2,325)	8,432	(2,325)
Hedging Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		(8,365)	(23,106)	(18,106)	(9,443)
Other comprehensive income (loss) before reclassifications		(3,514)	(3,669)	4,613	(18,059)
Amounts reclassified from accumulated other comprehensive income (loss)	[1]	2,208	2,412	4,360	3,381
Other Comprehensive Income (Loss), Tax		(552)	(603)	(1,090)	(845)
Other comprehensive income (loss)		(1,858)	(1,860)	7,883	(15,523)
Ending Balance		(10,223)	(24,966)	(10,223)	(24,966)
Pension and Other Postretirement Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		(70)	773	33	889
Other comprehensive income (loss) before reclassifications		(63)	186	5	241
Amounts reclassified from accumulated other comprehensive income (loss)	[2]	(228)	(228)	(456)	(456)
Other Comprehensive Income (Loss), Tax		57	57	114	114
Other comprehensive income (loss)		(234)	15	(337)	(101)
Ending Balance		(304)	788	(304)	788
Investments in Convertible Preferred Securities Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance		258	258	258	258
Other comprehensive income (loss)		0	0	0	0
Ending Balance		$ 258	$ 258	$ 258	$ 258

[1] Amounts reclassified from gain (loss) on cash flow hedges are reclassified from AOCI to income when the hedged item affects earnings and is recognized in Interest expense, net. See Note 5 for additional information.

[2] This accumulated other comprehensive loss component is included in the computation of net periodic benefit cost recorded in Operating, administrative and general expenses.