Equity and Accumulated Other Comprehensive Earnings - AOCI Activity (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Accumulated Other Comprehensive Earnings (Loss)
Stockholders' Equity Attributable to Parent, Beginning Balance		$ 2,949
Stockholders' Equity Attributable to Parent, Ending Balance	$ 2,762	2,762
Settlement loss	97	97
Foreign Currency Translation
Accumulated Other Comprehensive Earnings (Loss)
Stockholders' Equity Attributable to Parent, Beginning Balance		(340)
Other comprehensive earnings (loss) before reclassifications		(163)
Stockholders' Equity Attributable to Parent, Ending Balance	(503)	(503)
Pension and Other Postretirement Benefits (Net of Tax)
Accumulated Other Comprehensive Earnings (Loss)
Stockholders' Equity Attributable to Parent, Beginning Balance		(558)
Other comprehensive earnings (loss) before reclassifications		(104)
Amounts reclassified from accumulated other comprehensive earnings (loss) into earnings		94
Stockholders' Equity Attributable to Parent, Ending Balance	(568)	(568)
Effective Derivatives (Net of Tax)
Accumulated Other Comprehensive Earnings (Loss)
Stockholders' Equity Attributable to Parent, Beginning Balance		(12)
Other comprehensive earnings (loss) before reclassifications		18
Amounts reclassified from accumulated other comprehensive earnings (loss) into earnings		(3)
Stockholders' Equity Attributable to Parent, Ending Balance	3	3
Accumulated Other Comprehensive Earnings (Loss).
Accumulated Other Comprehensive Earnings (Loss)
Stockholders' Equity Attributable to Parent, Beginning Balance		(910)
Other comprehensive earnings (loss) before reclassifications		(249)
Amounts reclassified from accumulated other comprehensive earnings (loss) into earnings		91
Stockholders' Equity Attributable to Parent, Ending Balance	$ (1,068)	$ (1,068)