Commitments and Contingencies - Summary (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Investments in affordable housing projects
Tax Credit and Certain Equity Investments
Carrying amount	$ 4,107	$ 3,823
Amount of future funding commitments included in carrying amount	1,285	1,057
Lending exposure	763	546
Renewable Energy Investments
Tax Credit and Certain Equity Investments
Carrying amount	257	167
Amount of future funding commitments not included in carrying amount	71	76
Private equity and certain other equity method investments:
Tax Credit and Certain Equity Investments
Carrying amount	1,822	1,574
Amount of future funding commitments not included in carrying amount	$ 411	$ 471

Lending commitments to Affordable Housing Projects

No definition available.

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- Definition

Amount of investment in qualified affordable housing projects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
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-Topic 210
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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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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.

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- Definition

Amount of commitment or contingent commitments to qualified affordable housing project investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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