CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Unaudited - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income
Net income	$ 46	$ 775
Other Comprehensive Income, Net of Tax:
Unrealized holding gains on available-for-sale debt securities arising during period	882	430
Reclassification adjustment for net losses on available-for sale debt securities included in net income		1
Unrealized holding gains on cash flow hedge derivatives arising during period	427	87
Reclassification adjustment for net (gains) losses on cash flow hedge derivatives included in net income	(25)	2
Reclassification of amounts to net periodic benefit costs	1	1
Other comprehensive income, net of tax	1,285	521
Comprehensive Income	$ 1,331	$ 1,296