Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Fair market value adjustment on cash flow hedges, net of income tax (provision) benefit of ($2 million), $1 million, $0 million and $46 million	$ (2)	$ 1	$ 0	$ 46
Income tax provision on reclassification adjustment for net realized gain on cash flow hedges included in net interest expense	$ 1	$ 1	$ 4	$ 2

Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration