LOANS - Corporate Loans Credit Quality Indicators (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Loans receivable
Loans, net of unearned income	$ 653,183	$ 624,369
Loans at fair value	4,308	3,486
Corporate
Loans receivable
Loans, net of unearned income	327,607	299,306
Total non-accrual	2,054	2,421
Loans at fair value	4,281	3,457
Corporate \| Commercial and industrial
Loans receivable
Loans, net of unearned income	141,242	129,116
Total non-accrual	1,468	1,909
Corporate \| Financial institutions
Loans receivable
Loans, net of unearned income	69,805	61,560
Total non-accrual	224	185
Corporate \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	49,634	44,031
Total non-accrual	169	139
Corporate \| Lease financing
Loans receivable
Loans, net of unearned income	1,699	1,769
Total non-accrual	60	56
Corporate \| Other
Loans receivable
Loans, net of unearned income	60,946	59,373
Total non-accrual	133	132
Corporate \| Private bank loans managed on a delinquency basis
Loans receivable
Loans, net of unearned income	25,108	23,353
Corporate \| Investment grade
Loans receivable
Loans, net of unearned income	237,140	210,647
Corporate \| Investment grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	100,024	87,201
Corporate \| Investment grade \| Financial institutions
Loans receivable
Loans, net of unearned income	58,666	50,597
Corporate \| Investment grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	22,102	18,718
Corporate \| Investment grade \| Lease financing
Loans receivable
Loans, net of unearned income	1,117	1,303
Corporate \| Investment grade \| Other
Loans receivable
Loans, net of unearned income	55,231	52,828
Corporate \| Non-investment grade
Loans receivable
Loans, net of unearned income	61,078	61,849
Corporate \| Non-investment grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	39,750	39,874
Total non-accrual	1,468	1,909
Corporate \| Non-investment grade \| Financial institutions
Loans receivable
Loans, net of unearned income	10,916	10,873
Total non-accrual	224	185
Corporate \| Non-investment grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	2,256	1,821
Total non-accrual	169	139
Corporate \| Non-investment grade \| Lease financing
Loans receivable
Loans, net of unearned income	522	410
Total non-accrual	60	56
Corporate \| Non-investment grade \| Other
Loans receivable
Loans, net of unearned income	5,580	6,450
Total non-accrual	$ 133	$ 132

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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 (a)
-URI http://asc.fasb.org/extlink&oid=84173941&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=82891408&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=84173941&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
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-URI http://asc.fasb.org/subtopic&trid=2196772

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