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Derivative Instruments and Hedging Activities (Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location) (Details) - USD ($) $ in Millions | Jun. 30, 2020 | Dec. 31, 2019
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Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Closed Portfolio and Beneficial Interest, Last-of-Layer, Amortized Cost | $ 597 | $ 230
Available-for-sale securities |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Hedged Asset, Fair Value Hedge | 1,270 | 1,217
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease) | 50 | 18
Hedged asset, last-of-layer, amount | 490 | 0
Hedge basis adjustment, last-of-layer | 3 |
Finance receivables and Loans, net |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Hedged Asset, Fair Value Hedge | 36,211 | 33,312
Hedged Asset, Fair Value Hedge, Cumulative Increase (Decrease) | 334 | 135
Hedged asset, last-of-layer, amount | 10,200 | 10,200
Hedge basis adjustment, last-of-layer | 255 | 91
Long-term debt |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Hedged Liability, Fair Value Hedge | 10,020 | 11,995
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) | 196 | 24
Discontinued hedge | Available-for-sale securities |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 32 | 18
Hedged asset, last-of-layer, amount | 690 | 200
Hedge basis adjustment, last-of-layer | 22 | 2
Discontinued hedge | Finance receivables and Loans, net |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | 79 | 44
Hedged asset, last-of-layer, amount | 17,500 | 12,800
Hedge basis adjustment, last-of-layer | 79 | 43
Discontinued hedge | Long-term debt |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | $ 196 | $ 127

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- Definition Amortized cost of closed portfolio of prepayable financial asset and beneficial interest secured by prepayable financial instrument, 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=109980867&loc=SL109999718-113959 + Details
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