Total amount of portfolio loans sold and or reclassified to loans held-for-sale during the period.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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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.

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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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LOANS - Corporate Loans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
LOANS - Corporate Loans (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Loans
Loans, net of unearned income	$ 674,909		$ 674,909		$ 667,034
Corporate
Loans
Total loans	350,227		350,227		334,141
Net unearned income	(787)		(787)		(763)
Loans, net of unearned income	349,440		349,440		333,378
Loans sold and/or reclassified to held-for-sale	300	$ 100	800	$ 600
Corporate \| Commercial and industrial
Loans
Loans, net of unearned income	147,195		147,195		141,322
Corporate \| Financial institutions
Loans
Loans, net of unearned income	82,528		82,528		73,757
Corporate \| Mortgage and real estate
Loans
Loans, net of unearned income	54,964		54,964		51,964
Corporate \| Lease financing
Loans
Loans, net of unearned income	1,576		1,576		1,655
Corporate \| In U.S. offices
Loans
Total loans	178,895		178,895		169,781
Corporate \| In U.S. offices \| Commercial and industrial
Loans
Total loans	51,365		51,365		51,319
Corporate \| In U.S. offices \| Financial institutions
Loans
Total loans	46,255		46,255		39,128
Corporate \| In U.S. offices \| Mortgage and real estate
Loans
Total loans	47,629		47,629		44,683
Corporate \| In U.S. offices \| Installment, revolving credit and other
Loans
Total loans	32,201		32,201		33,181
Corporate \| In U.S. offices \| Lease financing
Loans
Total loans	1,445		1,445		1,470
Corporate \| In offices outside the U.S.
Loans
Total loans	171,332		171,332		164,360
Corporate \| In offices outside the U.S. \| Commercial and industrial
Loans
Total loans	98,281		98,281		93,750
Corporate \| In offices outside the U.S. \| Financial institutions
Loans
Total loans	37,851		37,851		35,273
Corporate \| In offices outside the U.S. \| Mortgage and real estate
Loans
Total loans	7,344		7,344		7,309
Corporate \| In offices outside the U.S. \| Installment, revolving credit and other
Loans
Total loans	22,827		22,827		22,638
Corporate \| In offices outside the U.S. \| Lease financing
Loans
Total loans	131		131		190
Corporate \| In offices outside the U.S. \| Government and official institutions
Loans
Total loans	$ 4,898		$ 4,898		$ 5,200