Derivative Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Notional derivative contracts	$ 9,900
Net positive exposure	52	$ 27
Estimated reclassification of AOCI to interest expense	5
Cash collateral pledged	53	$ 27
CME
Derivative [Line Items]
Notional derivative contracts	$ 9,400
Notional derivative contracts, percent	95.00%
Amount of variation margin included as settlement	$ (107)
LCH
Derivative [Line Items]
Notional derivative contracts	$ 500
Notional derivative contracts, percent	5.00%
Amount of variation margin included as settlement	$ 8

Amount Of Variation Margin Included As Settlement

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- Definition

Derivative, Notional Amount, Percent

+ References

No definition available.

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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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.

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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
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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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