Recorded Lower Of Amortized Cost Or Fair Value Adjustment

No definition available.

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Namespace Prefix:	hsbcusa_
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Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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Balance Type:	na
Period Type:	duration

- Definition

Amount of decrease in financing receivable from sale. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of gain (loss) from sale of financing receivable, including, but not limited to, lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481326/860-20-50-5

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Data Type:	xbrli:monetaryItemType
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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
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- Definition

Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
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-Publisher FASB
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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details

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- Details

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- Details

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- Details

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Loans Held for Sale - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	$ 1,305		$ 1,305		$ 1,925
Valuation allowance	0		0		0
Commercial loans held for sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale, fair value	795		795		626
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	1,303		1,303		1,923
Loans Transferred From Portfolio Loans to Held For Sale \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans held for sale	86		86		45
Lower of amortized cost or fair value adjustment	0	$ 0	0	$ 0
Commercial mortgages \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans sold, carrying value			1,100
Loss on sale of loans			0
Transfer of loans to held for sale, net	200
Total loans held for sale	$ 422		$ 422		$ 1,252