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Derivatives (Derivatives Not Designated as Hedging Instruments - Credit Contracts) (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Derivative [Line Items] |  |
Derivative assets - Fair value | $ 457,317 | $ 602,754
Derivative liabilities - Fair value | 344,135 | 424,828
Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional Amount | 22,005,910 | 21,341,158
Derivative assets - Fair value | 456,409 | 602,754
Derivative liabilities - Fair value | 342,877 | 422,729
Credit contracts | Derivatives not designated as hedging instruments | Other credit derivatives |  |
Derivative [Line Items] |  |
Notional Amount | 76,992 | 76,992
Derivative assets - Fair value | 5 | 13
Derivative liabilities - Fair value | 153 | 206
Credit contracts | Derivatives not designated as hedging instruments | Other credit derivatives | RPAs - protection sold |  |
Derivative [Line Items] |  |
Notional Amount | 66,278 | 66,278
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 153 | 206
Credit contracts | Derivatives not designated as hedging instruments | Other credit derivatives | RPAs - protection purchased |  |
Derivative [Line Items] |  |
Notional Amount | 10,714 | 10,714
Derivative assets - Fair value | 5 | 13
Derivative liabilities - Fair value | $ 0 | $ 0

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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset. + 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 (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset. + 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 (a) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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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 + Details
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