Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 1,550	$ 1,634
Other comprehensive income (loss):
Net unrealized securities (losses) gains, net of tax	17	(11)
Foreign currency translation adjustments, net of tax	8	30
Net unrealized Pension and other postretirement benefits, net of tax	(27)	28
Other comprehensive income (loss)	(2)	47
Comprehensive income	$ 1,548	$ 1,681

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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