Amount of write-down from impairment of an investment in a qualified affordable housing project.

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 (f)
-URI https://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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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.

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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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VARIABLE INTEREST ENTITIES - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Variable Interest Entity
Lending to special purpose entities included in loans and leases	$ 154,208,000,000		$ 154,208,000,000		$ 126,405,000,000
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Lending to special purpose entities included in loans and leases	3,341,000,000		3,341,000,000		2,646,000,000
Affordable housing project investment impairment losses	0	$ 0	0	$ 0
Variable Interest Entity, Not Primary Beneficiary \| Special Purpose Entities
Variable Interest Entity
Lending to special purpose entities included in loans and leases	3,300,000,000		3,300,000,000		2,600,000,000
Commitments to extend credit \| Variable Interest Entity, Not Primary Beneficiary \| Special Purpose Entities
Variable Interest Entity
Commitment amount	$ 2,400,000,000		$ 2,400,000,000		$ 1,900,000,000