Financial Statements of HSBC USA Inc. (Parent) Balance Sheet (Phantom) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Condensed Financial Statements, Captions [Line Items]
Securities held-to-maturity, fair value	$ 17,029	$ 14,689
2025	7,172
2026	2,063
2027	3,639
2028	1,423
2029	1,470
Thereafter	4,950
HSBC USA
Condensed Financial Statements, Captions [Line Items]
Securities held-to-maturity, fair value		$ 1
2025	7,200
2026	2,100
2027	3,500
2028	1,100
2029	1,500
Thereafter	$ 2,400

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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