Derivative Instruments and Hedging Activities (Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Available-for-sale securities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedged asset, fair value hedge	$ 5,405	$ 5,119
Hedged asset, fair value hedge, cumulative increase (decrease)	(59)	(14)
Closed portfolio and beneficial interest, last-of-layer, amortized cost	4,100	3,900
Hedge basis adjustment, last-of-layer increase (decrease)	(44)	(6)
Hedged asset, last-of-layer, amount	2,000	1,200
Available-for-sale securities \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedge basis adjustment, last-of-layer increase (decrease)	10	14
Finance receivables and loans, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedged asset, fair value hedge	43,485	44,098
Hedged asset, fair value hedge, cumulative increase (decrease)	(350)	(37)
Hedge basis adjustment, last-of-layer increase (decrease)	(350)	(37)
Hedged asset, last-of-layer, amount	17,600	15,600
Finance receivables and loans, net \| Designated as hedging instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedge basis adjustment, last-of-layer increase (decrease)	(386)	(82)
Long-term debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedged liability, fair value hedge	7,190	7,213
Hedged liability, fair value hedge, cumulative increase (decrease)	112	110
Discontinued hedge \| Available-for-sale securities
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedged asset, discontinued fair value hedge, cumulative increase (decrease)	(68)	(30)
Hedge basis adjustment, last-of-layer increase (decrease)	(54)	(20)
Discontinued hedge \| Finance receivables and loans, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedged asset, discontinued fair value hedge, cumulative increase (decrease)	36	46
Hedge basis adjustment, last-of-layer increase (decrease)	36	46
Discontinued hedge \| Long-term debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Hedged liability, discontinued fair value hedge, cumulative increase (decrease)	$ 110	$ 110

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.

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=125515794&loc=SL109999718-113959

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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)
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Amount of asset hedged in fair value hedging relationship.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
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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=125515794&loc=SL109999712-113959

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Amount of asset hedged in last of 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 (b)
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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, in last-of-layer 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 (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999718-113959

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge.

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Amount of liability hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 4EE
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-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109999712-113959

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