LOANS - Corporate Loans Credit Quality Indicators (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Loans receivable
Loans, net of unearned income	$ 699,483	$ 684,196
Loans at fair value	4,085	3,223
Corporate
Loans receivable
Loans, net of unearned income	389,935	381,836
Loans, total non-accrual	2,188	1,511
Loans at fair value	4,067	3,203
Corporate \| Commercial and industrial
Loans receivable
Loans, net of unearned income	166,846	174,890
Loans, total non-accrual	1,828	1,119
Corporate \| Financial institutions
Loans receivable
Loans, net of unearned income	91,852	85,284
Loans, total non-accrual	50	102
Corporate \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	63,151	57,500
Loans, total non-accrual	188	215
Corporate \| Lease financing
Loans receivable
Loans, net of unearned income	1,385	1,532
Loans, total non-accrual	41	0
Corporate \| Other
Loans receivable
Loans, net of unearned income	62,634	59,427
Loans, total non-accrual	81	75
Corporate \| Private Banking loans managed on a delinquency basis
Loans receivable
Loans, net of unearned income	31,590	27,656
Corporate \| Investment Grade
Loans receivable
Loans, net of unearned income	277,056	274,208
Corporate \| Investment Grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	110,797	113,925
Corporate \| Investment Grade \| Financial institutions
Loans receivable
Loans, net of unearned income	80,533	73,533
Corporate \| Investment Grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	27,571	26,799
Corporate \| Investment Grade \| Lease financing
Loans receivable
Loans, net of unearned income	816	1,035
Corporate \| Investment Grade \| Other
Loans receivable
Loans, net of unearned income	57,339	58,916
Corporate \| Non-Investment Grade
Loans receivable
Loans, net of unearned income	77,222	76,769
Corporate \| Non-Investment Grade \| Commercial and industrial
Loans receivable
Loans, net of unearned income	54,220	53,942
Loans, total non-accrual	1,828	1,119
Corporate \| Non-Investment Grade \| Financial institutions
Loans receivable
Loans, net of unearned income	11,269	10,866
Loans, total non-accrual	50	102
Corporate \| Non-Investment Grade \| Mortgage and real estate
Loans receivable
Loans, net of unearned income	3,811	4,200
Loans, total non-accrual	188	215
Corporate \| Non-Investment Grade \| Lease financing
Loans receivable
Loans, net of unearned income	528	497
Loans, total non-accrual	41	0
Corporate \| Non-Investment Grade \| Other
Loans receivable
Loans, net of unearned income	5,206	5,753
Loans, total non-accrual	$ 81	$ 75

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Amount of financing receivable on nonaccrual status.

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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.

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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.

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