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 http://asc.fasb.org/extlink&oid=114775393&loc=SL49122993-202985

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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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
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Variable Interest Entity
Lending to special purpose entities included in loans and leases	$ 117,615,000,000		$ 116,660,000,000
LIHTC Investments
Variable Interest Entity
Net impairment losses recognized in earnings	0	$ 0
Commercial \| Special Purpose Entities
Variable Interest Entity
Lending to special purpose entities included in loans and leases	728,000,000		613,000,000
Commitments to extend credit \| Special Purpose Entities
Variable Interest Entity
Commitment amount	$ 677,000,000		$ 584,000,000