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Derivatives and Hedging Activities - Credit Risk Contingent Feature (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | $ 2 |
One Rating Downgrade [Member] | Moody's, A3 Rating [Member] |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | $ 2
One Rating Downgrade [Member] | Standard & Poor's, A- Rating [Member] |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | 2
Two Rating Downgrade [Member] | Moody's, A3 Rating [Member] |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | 2
Two Rating Downgrade [Member] | Standard & Poor's, A- Rating [Member] |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | 2
Three Rating Downgrade [Member] | Moody's, A3 Rating [Member] |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | 1 | 2
Three Rating Downgrade [Member] | Standard & Poor's, A- Rating [Member] |  |
Credit Derivatives [Line Items] |  |
Additional collateral aggregate fair value | $ 1 | $ 2

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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=109980867&loc=SL5624258-113959 + Details
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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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