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		6 Months Ended
LOANS - Corporate Loans (Details) - USD ($) $ in Millions	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Loans
Loans, net of unearned income	$ 671,180		$ 671,180		$ 667,034
Corporate
Loans
Total loans	348,350		348,350		334,141
Net unearned income	(802)		(802)		(763)
Loans, net of unearned income	347,548		347,548		333,378
Loans sold and/or reclassified to held-for-sale	400	$ 0	500	$ 500
Corporate \| Commercial and industrial
Loans
Loans, net of unearned income	148,947		148,947		141,322
Corporate \| Financial institutions
Loans
Loans, net of unearned income	80,547		80,547		73,757
Corporate \| Mortgage and real estate
Loans
Loans, net of unearned income	53,551		53,551		51,964
Corporate \| Lease financing
Loans
Loans, net of unearned income	1,585		1,585		1,655
Corporate \| In U.S. offices
Loans
Total loans	176,545		176,545		169,781
Corporate \| In U.S. offices \| Commercial and industrial
Loans
Total loans	53,260		53,260		51,319
Corporate \| In U.S. offices \| Financial institutions
Loans
Total loans	42,867		42,867		39,128
Corporate \| In U.S. offices \| Mortgage and real estate
Loans
Total loans	46,310		46,310		44,683
Corporate \| In U.S. offices \| Installment, revolving credit and other
Loans
Total loans	32,663		32,663		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	171,805		171,805		164,360
Corporate \| In offices outside the U.S. \| Commercial and industrial
Loans
Total loans	98,068		98,068		93,750
Corporate \| In offices outside the U.S. \| Financial institutions
Loans
Total loans	38,312		38,312		35,273
Corporate \| In offices outside the U.S. \| Mortgage and real estate
Loans
Total loans	7,261		7,261		7,309
Corporate \| In offices outside the U.S. \| Installment, revolving credit and other
Loans
Total loans	22,755		22,755		22,638
Corporate \| In offices outside the U.S. \| Lease financing
Loans
Total loans	139		139		190
Corporate \| In offices outside the U.S. \| Government and official institutions
Loans
Total loans	$ 5,270		$ 5,270		$ 5,200