Derivatives and Risk Management Activities - Broker Receivable/Payable (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Offsetting Assets, Liabilities [Line Items]
Initial margin	$ 163	$ 73
Variation margin posted/(returned)	(214)	(45)
Letters of credit	(106)	(157)
Net broker payable	(125)	(45)
Exchange traded
Offsetting Assets, Liabilities [Line Items]
Letters of credit	$ (74)	$ (73)

The amount of cash or securities required by a broker or counterparty as security for a trading or derivatives securities position.

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- References

No definition available.

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- Definition

Cash posted by (returned to) the reporting entity to (from) a broker or counterparty to comply with initial margin requirements.

+ References

No definition available.

+ Details

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- Definition

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: 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

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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