Derivative Instruments - Effect of Fair Value Hedge Accounting (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Mortgage loans	$ 98,930	$ 106,316	$ 117,374
Long-term debt interest expense	(70,084)	$ (82,521)	$ (98,388)
Interest Rate Risk On Held-for-Investment Mortgage Loan \| Interest Income
Derivative [Line Items]
Net impact of hedged mortgage assets and debt	140
Discontinued hedge-related basis adjustment amortization	(6)
Derivatives designated as hedging instruments	(145)
Interest accruals on derivative hedging instruments	(12)
Gains (losses) recognized in net interest income on fair value hedging relationships	(23)
Interest Rate Risk On Debt \| Interest Expense
Derivative [Line Items]
Net impact of hedged mortgage assets and debt	1,370
Discontinued hedge-related basis adjustment amortization	(89)
Derivatives designated as hedging instruments	(1,308)
Interest accruals on derivative hedging instruments	223
Gains (losses) recognized in net interest income on fair value hedging relationships	$ 196

Discontinued hedge related basis adjustment amortization

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- Definition

Interest Accruals On Hedging Instruments

+ References

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=121577467&loc=d3e76258-113986

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- Definition

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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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.

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No definition available.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the 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 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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- Definition

The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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Aggregate amount of interest paid or due on all long-term debt.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.8)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (a)

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-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Paragraph (b)
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