Financial Statements of HSBC USA Inc. (Parent) Balance Sheet (Parenthetical) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Securities held-to-maturity, fair value	$ 1,499	$ 1,831
2014	3,926
2015	4,333
2016	1,462
2017	1,859
2018	3,066
Thereafter	8,201
HSBC USA Inc [Member]
Condensed Financial Statements, Captions [Line Items]
Securities held-to-maturity, fair value		0
2014	2,900
2015	4,300
2016	1,500
2017	1,300
2018	3,000
Thereafter	$ 3,000

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Fair value of investments in debt securities classified as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

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-Name Accounting Standards Codification

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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