Other Comprehensive Income (Loss) - Changes in AOCI Balances by Component (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	$ 1,584,092	$ 2,980,253
Total OCI, net of tax	(123,697)	45,395
Balance, end of year	1,210,165	2,976,717
Accumulated OCI, Net
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(379,873)	(543,531)
Other comprehensive income (loss) before reclassifications	(120,448)	41,943
Amounts reclassified from AOCI	968	2,967
Total OCI, net of tax	(119,480)	44,910
Balance, end of year	(499,353)	(498,621)
Foreign Currency Translation
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(242,950)	(309,800)
Other comprehensive income (loss) before reclassifications	(106,884)	41,711
Amounts reclassified from AOCI	0	0
Total OCI, net of tax	(106,884)	41,711
Balance, end of year	(349,834)	(268,089)
Ownership Share of Equity Method Investees’ Other Comprehensive Income (Loss)
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(35,456)	(23,672)
Other comprehensive income (loss) before reclassifications	(8,313)	(2,464)
Amounts reclassified from AOCI	141	142
Total OCI, net of tax	(8,172)	(2,322)
Balance, end of year	(43,628)	(25,994)
Defined Benefit Pension and Postretirement Plans
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(99,197)	(204,649)
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from AOCI	1,046	2,064
Total OCI, net of tax	1,046	2,064
Balance, end of year	(98,151)	(202,585)
Unrealized Gain (Loss) on Derivative Contracts
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(2,270)	(5,410)
Other comprehensive income (loss) before reclassifications	(5,251)	2,696
Amounts reclassified from AOCI	(219)	761
Total OCI, net of tax	(5,470)	3,457
Balance, end of year	(7,740)	(1,953)
Accumulated Other Comprehensive Income (Loss), Net Attributable to Noncontrolling Interests
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(5,051)	(3,701)
Balance, end of year	(9,268)	(3,216)
Foreign Currency Translation
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(5,051)	(3,701)
Other comprehensive income (loss) before reclassifications	(4,217)	485
Amounts reclassified from AOCI	0	0
Total OCI, net of tax	(4,217)	485
Balance, end of year	(9,268)	(3,216)
Ownership Share of Equity Method Investees’ Other Comprehensive Income (Loss)
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	0	0
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from AOCI	0	0
Total OCI, net of tax	0	0
Balance, end of year	0	0
Defined Benefit Pension and Postretirement Plans
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	0	0
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from AOCI	0	0
Total OCI, net of tax	0	0
Balance, end of year	0	0
Unrealized Gain (Loss) on Derivative Contracts
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	0	0
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from AOCI	0	0
Total OCI, net of tax	0	0
Balance, end of year	0	0
Noncontrolling Interests
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	96,340	146,128
Other comprehensive income (loss) before reclassifications	(4,217)	485
Amounts reclassified from AOCI	0	0
Total OCI, net of tax	(4,217)	485
Balance, end of year	$ 118,520	$ 163,612

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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