Financial Statements of HSBC USA Inc. (Parent) Balance Sheet (Details) - USD ($) $ in Millions		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Assets:
Securities held-to-maturity, net of allowance for credit losses of less than $1 million at December 31, 2020 (fair value of $2 million at both December 31, 2020 and 2019, respectively)		$ 8,981		$ 13,293
Investment in subsidiaries:
Other Assets		6,084		6,723
Total assets		196,434	[1]	175,375	[1]	$ 172,448
Liabilities:
Interest, taxes and other liabilities		2,665		3,835
Total liabilities	[1]	178,143		157,119
Total equity		18,291		18,256		$ 20,506
Total liabilities and equity		196,434		175,375
HSBC USA Inc [Member]
Assets:
Securities held-to-maturity, net of allowance for credit losses of less than $1 million at December 31, 2020 (fair value of $2 million at both December 31, 2020 and 2019, respectively)		2		2
Receivables and balances due from subsidiaries		14,585		14,044
Receivables from other HSBC affiliates		1,276		2,335
Investment in subsidiaries:
Banking		21,897		21,753
Other		12		12
Other Assets		182		204
Total assets		37,954		38,350
Liabilities:
Interest, taxes and other liabilities		85		137
Payables due to subsidiaries		4		3
Payables due to other HSBC affiliates		32		35
Short-term borrowings		2,998		2,476
Short-term borrowings due to subsidiaries	[2]	3,000		0
Long-term debt	[3]	10,695		14,595
Long-term debt due to subsidiary and other HSBC affiliates	[3]	2,849		2,848
Total liabilities		19,663		20,094
Total equity		18,291		18,256
Total liabilities and equity		$ 37,954		$ 38,350

[1] Assets

[2] Reflects a borrowing due to HSBC Bank USA which matures at the end of February 2021. The borrowing will be re-evaluated prior to its maturity date and either extended or allowed to mature.

[3] Contractual scheduled maturities for the debt over the next five years are as follows: 2021 – $3.0 billion; 2022 – $2.9 billion; 2023 – $1.5 billion; 2024 – $1.5 billion; 2025 – $3.8 billion; and thereafter – $0.8 billion