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

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Amount, before allowance for credit loss, of financing receivable.

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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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VARIABLE INTEREST ENTITIES - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Variable Interest Entity
Lending to special purpose entities included in loans and leases	$ 122,581,000,000		$ 122,581,000,000		$ 123,090,000,000
LIHTC Investments
Variable Interest Entity
Net impairment losses recognized in earnings	0	$ 0	0	$ 0
Commitments to extend credit \| Special Purpose Entities
Variable Interest Entity
Commitment amount	1,700,000,000		1,700,000,000		1,500,000,000
Commercial and industrial \| Special Purpose Entities
Variable Interest Entity
Lending to special purpose entities included in loans and leases	1,520,000,000		1,520,000,000		1,295,000,000
Retail
Variable Interest Entity
Lending to special purpose entities included in loans and leases	63,498,000,000		63,498,000,000		62,297,000,000
Retail \| Education
Variable Interest Entity
Lending to special purpose entities included in loans and leases	$ 12,800,000,000		$ 12,800,000,000		$ 12,308,000,000