Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive (Loss) by Component (Details) - USD ($) $ in Thousands		6 Months Ended
	Mar. 07, 2019	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019
AOCI Attributable to Parent [Roll Forward]
Beginning balance		$ 3,450,451
Other comprehensive income (loss) before reclassifications, net of tax		10,109	$ (105,068)
Amounts reclassified from accumulated other comprehensive loss, net of tax		32,316	14,309
Other comprehensive income (loss), net of income taxes		42,425	(90,759)
Ending balance		3,665,328
Realized currency losses on divestiture	$ 27,037	27,037	0
Pension and Other Post-Retirement Benefits
AOCI Attributable to Parent [Roll Forward]
Beginning balance		(626,322)	(568,957)
Other comprehensive income (loss) before reclassifications, net of tax		0	0
Amounts reclassified from accumulated other comprehensive loss, net of tax		9,665	14,309
Other comprehensive income (loss), net of income taxes		9,665	14,309
Cumulative effect from adoption of ASU 2018-02				$ (122,526)
Ending balance		(739,183)	(554,648)
Net Investment Hedge
AOCI Attributable to Parent [Roll Forward]
Beginning balance		10,726	(17,388)
Other comprehensive income (loss) before reclassifications, net of tax		(835)	16,045
Amounts reclassified from accumulated other comprehensive loss, net of tax		(4,386)	0
Other comprehensive income (loss), net of income taxes		(5,221)	16,045
Cumulative effect from adoption of ASU 2018-02				0
Ending balance		5,505	(1,343)
Foreign Currency Translation
AOCI Attributable to Parent [Roll Forward]
Beginning balance		(499,482)	(266,247)
Other comprehensive income (loss) before reclassifications, net of tax		10,944	(121,113)
Amounts reclassified from accumulated other comprehensive loss, net of tax		27,037	0
Other comprehensive income (loss), net of income taxes		37,981	(121,113)
Cumulative effect from adoption of ASU 2018-02				0
Ending balance		(461,501)	(387,360)
Total
AOCI Attributable to Parent [Roll Forward]
Beginning balance		(1,115,078)	(852,592)
Cumulative effect from adoption of ASU 2018-02				$ (122,526)
Ending balance		$ (1,195,179)	$ (943,351)