LOANS - Corporate Loans Credit Quality Indicators (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Loans receivable
Loans, net of unearned income	$ 617,617	$ 644,635
Loans at fair value	5,005	5,901
Corporate
Loans receivable
Loans, net of unearned income	291,832	278,692
Loans, total non-accrual	1,596	1,202
Loans at fair value	4,971	5,858
Corporate \| Commercial and industrial
Loans receivable
Loans, net of unearned income	119,627	114,353
Loans, total non-accrual	1,071	594
Corporate \| Financial institutions
Loans receivable
Loans, net of unearned income	64,317	67,832
Loans, total non-accrual	173	250
Corporate \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	42,471	38,473
Loans, total non-accrual	232	252
Corporate \| Lease financing
Loans receivable
Loans, net of unearned income	2,082	2,176
Loans, total non-accrual	76	51
Corporate \| Other
Loans receivable
Loans, net of unearned income	58,359	49,949
Loans, total non-accrual	44	55
Corporate \| Private Banking loans managed on a delinquency basis
Loans receivable
Loans, net of unearned income	20,575	18,616
Corporate \| Investment Grade
Loans receivable
Loans, net of unearned income	211,393	204,995
Corporate \| Investment Grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	85,893	84,820
Corporate \| Investment Grade \| Financial institutions
Loans receivable
Loans, net of unearned income	53,522	56,154
Corporate \| Investment Grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	18,869	16,068
Corporate \| Investment Grade \| Lease financing
Loans receivable
Loans, net of unearned income	1,660	1,669
Corporate \| Investment Grade \| Other
Loans receivable
Loans, net of unearned income	51,449	46,284
Corporate \| Non-Investment Grade
Loans receivable
Loans, net of unearned income	54,893	49,223
Corporate \| Non-Investment Grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	32,726	29,003
Loans, total non-accrual	1,071	594
Corporate \| Non-Investment Grade \| Financial institutions
Loans receivable
Loans, net of unearned income	10,622	11,429
Loans, total non-accrual	173	250
Corporate \| Non-Investment Grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	2,800	3,587
Loans, total non-accrual	232	252
Corporate \| Non-Investment Grade \| Lease financing
Loans receivable
Loans, net of unearned income	282	393
Loans, total non-accrual	76	51
Corporate \| Non-Investment Grade \| Other
Loans receivable
Loans, net of unearned income	6,867	3,609
Loans, total non-accrual	$ 44	$ 55

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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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