Accumulated Other Comprehensive Loss - Changes in AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accumulated other comprehensive loss, net of tax
Beginning balance	$ (970,782)	$ (749,807)	$ (716,118)	$ (643,093)
Net current period change			(36,196)
Amounts reclassified from AOCI			2,248
Amounts reclassified due to de-designation			11,208
Ending balance	(1,076,705)	(635,187)	(1,076,705)	(635,187)
Cumulative Translation Adjustment
Accumulated other comprehensive loss, net of tax
Beginning balance			(22,184)
Net current period change			(13,553)
Ending balance	(35,737)		(35,737)
Cash Flow Hedges
Accumulated other comprehensive loss, net of tax
Beginning balance			(1,530)
Net current period change			(33,948)
Amounts reclassified from AOCI			2,244
Amounts reclassified due to de-designation			14,928
Ending balance	(18,306)		(18,306)
Defined Benefit Plans
Accumulated other comprehensive loss, net of tax
Beginning balance			(49,282)
Amounts reclassified from AOCI			750
Ending balance	(48,532)		(48,532)
Income Taxes
Accumulated other comprehensive loss, net of tax
Beginning balance			(1,714)
Net current period change			11,305
Amounts reclassified from AOCI			(746)
Amounts reclassified due to de-designation			(3,720)
Ending balance	5,125		5,125
Accumulated other comprehensive loss
Accumulated other comprehensive loss, net of tax
Beginning balance	(99,421)	(71,635)	(74,710)	(71,498)
Ending balance	$ (97,450)	$ (75,218)	$ (97,450)	$ (75,218)