Other Comprehensive Income (Loss) - Changes in AOCI Balances by Component (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	$ 2,497,489	$ 3,184,840	$ 3,118,050	$ 3,492,399
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(43,644)	(59,983)	(10,968)	(81,219)
Balance, end of year	1,683,930	3,199,929	1,683,930	3,199,929
Foreign Currency Translation
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(281,288)	(242,917)	(308,747)	(211,177)
Other comprehensive income (loss) before reclassifications	(40,253)	(11,333)	(12,794)	(43,073)
Amounts reclassified from AOCI	0	0	0	0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(40,253)	(11,333)	(12,794)	(43,073)
Balance, end of year	(321,541)	(254,250)	(321,541)	(254,250)
Ownership Share of Equity Method Investees’ Other Comprehensive Income (Loss)
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(28,459)	(20,064)	(23,672)	(32,614)
Other comprehensive income (loss) before reclassifications	2,518	(6,646)	(2,552)	5,247
Amounts reclassified from AOCI	144	151	427	808
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	2,662	(6,495)	(2,125)	6,055
Balance, end of year	(25,797)	(26,559)	(25,797)	(26,559)
Defined Benefit Pension and Postretirement Plans
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(200,546)	(148,188)	(204,649)	(152,058)
Other comprehensive income (loss) before reclassifications	0	(56,191)	0	(56,191)
Amounts reclassified from AOCI	1,990	16,388	6,093	20,258
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	1,990	(39,803)	6,093	(35,933)
Balance, end of year	(198,556)	(187,991)	(198,556)	(187,991)
Unrealized Gain (Loss) on Derivative Contracts
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	285	(11,426)	(5,410)	(5,684)
Other comprehensive income (loss) before reclassifications	(6,844)	(3,736)	(2,519)	(10,785)
Amounts reclassified from AOCI	550	1,784	1,920	3,091
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(6,294)	(1,952)	(599)	(7,694)
Balance, end of year	(6,009)	(13,378)	(6,009)	(13,378)
Unrealized Gain (Loss) on Available-for- Sale Securities
Changes in AOCI balances by component (after-tax)
Balance, beginning of year		0		(709)
Other comprehensive income (loss) before reclassifications	(44,579)	0	(17,865)	0
Amounts reclassified from AOCI	2,684	0	8,440	709
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(41,895)	0	(9,425)	709
Balance, end of year		0		0
Unrealized Gain (Loss) on Derivative Contracts
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(510,008)	(422,595)	(542,478)	(402,242)
Other comprehensive income (loss) before reclassifications		(77,906)		(104,802)
Amounts reclassified from AOCI		18,323		24,866
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(41,895)	(59,583)	(9,425)	(79,936)
Balance, end of year	(551,903)	(482,178)	(551,903)	(482,178)
Accumulated Other Comprehensive Income (Loss), Net Attributable to Noncontrolling Interests
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(3,495)	(2,345)	(3,701)	(1,462)
Balance, end of year	(5,244)	(2,745)	(5,244)	(2,745)
Foreign Currency Translation
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	(3,495)	(2,345)	(3,701)	(1,462)
Other comprehensive income (loss) before reclassifications	(1,749)	(400)	(1,543)	(1,283)
Amounts reclassified from AOCI	0	0	0	0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(1,749)	(400)	(1,543)	(1,283)
Balance, end of year	(5,244)	(2,745)	(5,244)	(2,745)
Ownership Share of Equity Method Investees’ Other Comprehensive Income (Loss)
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	0	0	0	0
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	0	0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	0	0	0	0
Balance, end of year	0	0	0	0
Defined Benefit Pension and Postretirement Plans
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	0	0	0	0
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	0	0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	0	0	0	0
Balance, end of year	0	0	0	0
Unrealized Gain (Loss) on Derivative Contracts
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	0	0	0	0
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI	0	0	0	0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	0	0	0	0
Balance, end of year	0	0	0	0
Unrealized Gain (Loss) on Available-for- Sale Securities
Changes in AOCI balances by component (after-tax)
Balance, beginning of year		0		0
Other comprehensive income (loss) before reclassifications	(1,749)	0	(1,543)	0
Amounts reclassified from AOCI	0	0	0	0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(1,749)	0	(1,543)	0
Balance, end of year		0		0
Noncontrolling Interests
Changes in AOCI balances by component (after-tax)
Balance, beginning of year	123,252	141,485	154,869	150,089
Other comprehensive income (loss) before reclassifications		(400)		(1,283)
Amounts reclassified from AOCI		0		0
TOTAL OTHER COMPREHENSIVE LOSS, NET OF TAX	(1,749)	(400)	(1,543)	(1,283)
Balance, end of year	$ 124,435	$ 156,905	$ 124,435	$ 156,905

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

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