Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 6,759	$ 6,921	$ 2,748
Other comprehensive income (loss)
Net unrealized securities losses, net of tax	41	(8)	(7)
Foreign currency translation adjustments, net of tax	(56)	(172)	301
Net unrealized pension and other postretirement benefits, net of tax	(125)	11	62
Other comprehensive (loss) income	(140)	(169)	356
Comprehensive income	$ 6,619	$ 6,752	$ 3,104

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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