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Derivative Instruments and Hedging Activities - Hedged Items in Fair Value Hedging Relationship (Details) - USD ($) $ in Millions | Jun. 30, 2021 | Dec. 31, 2020
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Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Hedged Assets, Fair Value Hedge, Cumulative Increase (Decrease) | $ (1) |
Hedged Assets, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 249 |
Prepayable Financial Asset Closed Portfolio, Last-of-Layer, Amortized Cost | 225 |
Available-for-sale securities |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount of Assets | 9,936 | $ 9,797
Hedged Assets, Fair Value Hedge, Cumulative Increase (Decrease) | 467 | 590
Hedged Assets, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 188 | 200
Interest-bearing deposits |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Of Liabilities | (9,882) | (11,312)
Hedged Liabilities, Fair Value Hedge, Cumulative Increase (Decrease) | (124) | (213)
Hedged Liabilities, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 0 | 0
Securitized debt obligations |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Of Liabilities | (6,926) | (7,609)
Hedged Liabilities, Fair Value Hedge, Cumulative Increase (Decrease) | (84) | (171)
Hedged Liabilities, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 9 | 20
Senior and subordinated notes |  |
Hedged Items In Fair Value Hedging Relationship [Line Items] |  |
Carrying Amount Of Liabilities | (20,267) | (21,927)
Hedged Liabilities, Fair Value Hedge, Cumulative Increase (Decrease) | (879) | (1,282)
Hedged Liabilities, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | $ (597) | $ (666)

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- Definition The carry amount of liabilities in fair value hedging relationship + References No definition available. + Details
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- Definition [Line Items] for Table shows the carrying amount and associated cumulative basis adjustment related to the application of hedge accounting that is included in the carrying amount of hedged assets and liabilities in fair value hedging relationships. + References No definition available. + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999712-113959 + Details
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- Definition Amortized cost of closed portfolio of prepayable financial asset, used to designate hedging relationship in which hedged item is last layer expected to be remaining at end of hedging relationship. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EEE -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999718-113959 + Details
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