Derivatives - Cash Flow Hedges (Details) $ in Millions	6 Months Ended
Jun. 30, 2021 USD ($)
Interest rate contracts
Derivatives in Cash Flow Hedging Relationships
Derivative notional amount	$ 650
Cash flow hedge
Derivatives in Cash Flow Hedging Relationships
Accumulated other comprehensive income (loss), unrealized gain (loss) on cash flow hedges	(126)
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the income statement within next twelve months	30
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the income statement over remaining fiscal year	24
After-tax net unrealized gain (loss) anticipated to be reclassifed from AOCI to the income statement over next fiscal year	10
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the income statement after the next fiscal year	92
Cash flow hedge \| 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	$ (104)
Cash flow hedge \| Foreign currency exchange contracts
Derivatives in Cash Flow Hedging Relationships
Maximum length of time hedged in interest rate cash flow hedge	36 months

After-tax net unrealized gain (loss) anticipated to be reclassified out of AOCI one year after the next fiscal year.

No definition available.

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- Definition

After-tax net unrealized gain (loss) anticipated to be reclassifed out of AOCI within the next fiscal year.

+ References

No definition available.

+ Details

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- Definition

After-tax net unrealized gain (loss) anticipated to be reclassified out of AOCI within the remaining fiscal year.

+ References

No definition available.

+ Details

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- Definition

Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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=121641772&loc=d3e637-108580

+ Details

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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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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