Financial Statements of HSBC USA Inc. (Parent) Statement of Cash Flows (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ (338)	$ (1,045)	$ 1,018
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	59	61	77
Other, net	(481)	36	108
Net cash provided by (used in) operating activities	(1,359)	8,367	362
Cash flows from investing activities
Net change in interest bearing deposits with banks	(6,316)	12,175	(17,252)
Net change in loans	(4,765)	(11,603)	(6,034)
Other, net	(16)	(48)	(77)
Net cash provided by (used in) investing activities	1,233	(2,748)	(22,342)
Cash flows from financing activities
Net change in short-term borrowings	3,787	(1,076)	3,449
Issuance of long-term debt	5,547	7,626	6,271
Repayment of long-term debt	(4,370)	(3,445)	(6,274)
Dividends paid	(73)	(73)	(73)
Capital contribution from parent	0	312	0
Additions (reductions) of capital surplus	(17)	(3)	8
Net cash provided by (used in) financing activities	(272)	(5,876)	21,903
Net change in cash and due from banks	(398)	(257)	(77)
Cash paid for:
Interest	921	1,085	1,231
HSBC USA Inc [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(338)	(1,045)	1,018
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	37	1	14
Other, net	2,087	(3,177)	(997)
Undistributed loss (gain) of subsidiaries	(325)	951	(1,042)
Net change in trading assets and liabilities	362	(321)	(72)
Increase (Decrease), Other, Net	16	(58)	27
Net cash provided by (used in) operating activities	1,807	(3,533)	(1,106)
Cash flows from investing activities
Purchases of securities	(139)	(342)	0
Sales and maturities of securities	208	14	21
Net change in loans	5	5	10
Net change in investments in and advances to subsidiaries	(1,666)	(918)	(886)
Other, net	0	1	0
Net cash provided by (used in) investing activities	(1,592)	(1,240)	(855)
Cash flows from financing activities
Net change in short-term borrowings	(1,643)	186	1,809
Issuance of long-term debt	4,401	7,209	5,646
Repayment of long-term debt	(2,875)	(2,858)	(5,450)
Dividends paid	(73)	(73)	(73)
Capital contribution from parent	0	312	0
Additions (reductions) of capital surplus	(17)	(3)	29
Net cash provided by (used in) financing activities	(207)	4,773	1,961
Net change in cash and due from banks	8	0	0
Cash and due from banks at beginning of period	0	0	0
Cash and due from banks at end of period	8	0	0
Cash paid for:
Interest	$ 321	$ 317	$ 338