Allowance for credit losses on unfunded standby letters of credit.

No definition available.

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- Definition

Mortgage securitization outstanding loan purchase and sold.

+ References

No definition available.

+ Details

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- Definition

Pledged assets not separately reported trading assets.

+ References

No definition available.

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- Definition

Related Party, Whole Loan Securitization Program, Amounts of Transaction

+ References

No definition available.

+ Details

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
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- Definition

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it is permitted by contract or custom to sell or re-pledge to counterparties as collateral.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Fair value as of the balance sheet date of customer securities accepted as collateral by the entity that it has sold or re-pledged to counterparties as collateral.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
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Balance Type:	credit
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions where counterparty has the right to re-pledge such.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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- 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

No definition available.

+ Details

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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- Definition

Fair value of securities received as collateral against securities purchased under agreement to resell.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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- Details

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- Details

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- Details

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Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Additional Information (Detail) - USD ($)	36 Months Ended
	Dec. 31, 2007	Mar. 31, 2022	Dec. 31, 2021
Guarantor Obligations [Line Items]
Deferred fees		$ 4,000,000	$ 4,000,000
Carrying value of swap		1,463,311,000,000	1,395,345,000,000
Estimate of reasonably possible loss		150,000,000
Pledged assets not separately reported, trading assets		1,943,000,000	1,773,000,000
Collateral accepted under security resale agreements, fair value		10,798,000,000	12,848,000,000
Collateral accepted under security repurchase agreements but not reported on the balance sheet that can be sold or repledged, fair value		10,798,000,000	12,848,000,000
Collateral accepted under security repurchase agreements that has been sold or repledged under repurchase agreements or to cover short sales		2,125,000,000	538,000,000
Obligation to Repurchase Receivables Sold
Guarantor Obligations [Line Items]
Estimated repurchase liability		11,000,000	3,000,000
Obligation to Repurchase Receivables Sold \| Minimum
Guarantor Obligations [Line Items]
Estimate of reasonably possible loss		0
Obligation to Repurchase Receivables Sold \| Maximum
Guarantor Obligations [Line Items]
Estimate of reasonably possible loss		30,000,000
HSBC Securities
Guarantor Obligations [Line Items]
Whole loan securitization	$ 24,000,000,000
HSBC Securities \| Mortgage Securitization Activity Related Litigation
Guarantor Obligations [Line Items]
Mortgage securitization outstanding loan purchase and sold		2,700,000,000	2,700,000,000
Securities available-for-sale ("AFS")
Guarantor Obligations [Line Items]
Securities pledged as collateral that can be sold or repledged by the secured party, fair value		3,359,000,000	2,410,000,000
Trading assets
Guarantor Obligations [Line Items]
Pledged assets not separately reported, trading assets		1,943,000,000	1,749,000,000
Other liabilities
Guarantor Obligations [Line Items]
Allowance for credit losses on unfunded standby letters of credit		13,000,000	14,000,000
Other liabilities \| Standby Letters of Credit
Guarantor Obligations [Line Items]
Deferred fees		54,000,000	51,000,000
Swap
Guarantor Obligations [Line Items]
Carrying value of swap		$ 27,000,000	$ 38,000,000