Derivatives - Cash Flow Hedges (Details) - Cash flow hedge $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Derivatives in Cash Flow Hedging Relationships
Accumulated other comprehensive income (loss), unrealized gain (loss) on cash flow hedges	$ (78)
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the income statement within next twelve months	4
Interest rate swap and treasury lock in aggregate
Derivatives in Cash Flow Hedging Relationships
Accumulated other comprehensive income (loss), unrealized gain (loss) on cash flow hedges	$ (102)

Amount, after tax, of accumulated gain (loss) on 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 11
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e637-108580

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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+ References

No definition available.

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