Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 24, 2020
Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
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 Current Reporting Status	Yes
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