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Derivatives and Hedging Activities - Credit Risk Contingent Feature (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | $ 3 |
Standard & Poor's, A- Rating | One rating downgrade |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | $ 1
Standard & Poor's, A- Rating | Two rating downgrades |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 2 | 1
Standard & Poor's, A- Rating | Three rating downgrades |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 2 | 1
Moody's, A3 Rating | One rating downgrade |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | 1
Moody's, A3 Rating | Two rating downgrades |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 2 | 1
Moody's, A3 Rating | Three rating downgrades |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | $ 2 | $ 1

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- Definition The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959 + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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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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- Details
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- Details
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- Details
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- Details
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- Details
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