Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 1,761	$ 1,623	$ 3,311	$ 3,257
Other comprehensive (loss) income:
Net unrealized debt securities gains (losses), net of tax	26	(7)	43	(18)
Foreign currency translation adjustments, net of tax	(36)	(96)	(28)	(66)
Net unrealized pension and other postretirement benefits, net of tax	3	1	(24)	29
Other comprehensive (loss) income	(7)	(102)	(9)	(55)
Comprehensive income	$ 1,754	$ 1,521	$ 3,302	$ 3,202

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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