CONSOLIDATED STATEMENT OF INCOME (LOSS) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest income:
Loans		$ 2,856	$ 2,589	$ 2,241
Securities		1,188	1,131	952
Trading securities		291	213	209
Short-term investments		573	645	669
Other		82	77	52
Total interest income		4,990	4,655	4,123
Interest expense:
Deposits		1,475	1,072	703
Short-term borrowings		231	172	124
Long-term debt		1,137	1,123	998
Other		35	36	25
Total interest expense		2,878	2,403	1,850
Net interest income		2,112	2,252	2,273
Provision for credit losses		195	(73)	(165)
Net interest income after provision for credit losses		1,917	2,325	2,438
Other revenues:
Other revenues		1,184	1,236	1,233
Trading revenue		591	625	354
Other securities gains, net		88	24	52
Gain (loss) on instruments designated at fair value and related derivatives		(13)	19	43
Other income		16	6	334
Total other revenues	[1]	1,854	1,899	2,002
Operating expenses:
Salaries and employee benefits		822	830	1,077
Support services from HSBC affiliates		1,638	1,603	1,549
Occupancy expense, net		197	185	202
Goodwill impairment		365	0	0
Other expenses		479	1,020	563
Total operating expenses		3,501	3,638	3,391
Income before income tax		270	586	1,049
Income tax expense		157	266	1,228
Net income (loss)		113	320	(179)
Credit card fees, net [Member]
Other revenues:
Other revenues		67	50	46
Trust and investment management fees [Member]
Other revenues:
Other revenues		132	135	156
Other fees and commissions [Member]
Other revenues:
Other revenues		619	684	669
Servicing and other fees from HSBC affiliates [Member]
Other revenues:
Other revenues		$ 354	$ 356	$ 348

[1] See Note 24, "Business Segments," for a reconciliation of total other revenues on a U.S. GAAP basis to other operating income for each business segment under the Group Reporting Basis.