LOANS - Corporate Loans Credit Quality Indicators (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Loans receivable
Loans, net of unearned income	$ 618,824	$ 617,617
Loans at fair value	4,793	5,005
Corporate
Loans receivable
Loans, net of unearned income	300,924	291,832
Total non-accrual	2,327	1,596
Loans at fair value	4,760	4,971
Corporate \| Commercial and industrial
Loans receivable
Loans, net of unearned income	126,161	119,692
Total non-accrual	1,863	1,071
Corporate \| Financial institutions
Loans receivable
Loans, net of unearned income	64,437	64,317
Total non-accrual	164	173
Corporate \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	44,266	42,471
Total non-accrual	204	232
Corporate \| Lease financing
Loans receivable
Loans, net of unearned income	1,878	2,017
Total non-accrual	1	76
Corporate \| Other
Loans receivable
Loans, net of unearned income	59,416	58,359
Total non-accrual	95	44
Corporate \| Private Banking loans managed on a delinquency basis
Loans receivable
Loans, net of unearned income	20,971	20,575
Corporate \| Investment grade
Loans receivable
Loans, net of unearned income	217,307	211,393
Corporate \| Investment grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	88,145	85,893
Corporate \| Investment grade \| Financial institutions
Loans receivable
Loans, net of unearned income	54,961	53,522
Corporate \| Investment grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	20,540	18,869
Corporate \| Investment grade \| Lease financing
Loans receivable
Loans, net of unearned income	1,548	1,660
Corporate \| Investment grade \| Other
Loans receivable
Loans, net of unearned income	52,113	51,449
Corporate \| Non-investment grade
Loans receivable
Loans, net of unearned income	57,886	54,893
Corporate \| Non-investment grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	36,153	32,726
Total non-accrual	1,863	1,071
Corporate \| Non-investment grade \| Financial institutions
Loans receivable
Loans, net of unearned income	9,312	10,622
Total non-accrual	164	173
Corporate \| Non-investment grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	2,556	2,800
Total non-accrual	204	232
Corporate \| Non-investment grade \| Lease financing
Loans receivable
Loans, net of unearned income	329	282
Total non-accrual	1	76
Corporate \| Non-investment grade \| Other
Loans receivable
Loans, net of unearned income	7,209	6,867
Total non-accrual	$ 95	$ 44

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No definition available.

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Glossary Loan
-URI http://asc.fasb.org/extlink&oid=6517073

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