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		$ 3,571	$ 2,644	$ 3,064
Other Comprehensive (Loss) Income, net of tax(a)
Pension and OPEB adjustments	[1]	9	(6)	3
Net unrealized (losses) gains on cash flow hedges	[1]	(47)	(10)
Net unrealized (losses) gains on cash flow hedges	[1]			2
Reclassification into earnings from cash flow hedges	[1]	6	6
Reclassification into earnings from cash flow hedges	[1]			8
Unrealized gains (losses) on available-for-sale securities	[1]	8	(3)	13
Other Comprehensive (Loss) Income, net of tax	[1]	(24)	(13)	26
Comprehensive Income		3,547	2,631	3,090
Less: Comprehensive (Loss) Income Attributable to Noncontrolling Interests		(177)	(22)	5
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		3,724	2,653	3,085
Less: Preferred Dividends		41
Comprehensive (Loss) Income Attributable to Parent		$ 3,683	$ 2,653	$ 3,085

[1] Tax impacts are insignificant for all periods presented.