Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 2,235	$ 367
Other comprehensive income (loss):
Net unrealized debt securities (losses) gains, net of tax	(12)	57
Foreign currency translation adjustments, net of tax	(17)	(322)
Net unrealized pension and other postretirement benefits, net of tax	26	6
Other comprehensive income (loss)	(3)	(259)
Comprehensive income	$ 2,232	$ 108