Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 14, 2020	Jun. 30, 2019
Entity Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Registrant Name	HSBC USA INC /MD/
Entity Central Index Key	0000083246
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		714
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 0
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Zero Coupon Callable Accreting Notes due January 15, 2043 [Member]
Entity Information [Line Items]
Trading Symbol	HBA/43
Zero Coupon Callable Accreting Notes due January 29, 2043 [Member]
Entity Information [Line Items]
Trading Symbol	HBA/43A