Common Equity Tier One Capital Ratio, CECL Transition

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- Definition

Common Equity Tier One Capital Ratio, Excluding CECL Transition Adjustment

+ References

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- Definition

Regulatory Capital Adjustments, Net of Tax, CECL Transition

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- Definition

Regulatory Capital Adjustments, Net of Tax, CECL Transition, Phased in Amount

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- Definition

Statutory Accounting Practices, Statutory Amount Available for Dividend Payments per Share, Maximum

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

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Amount of dividends available for payment after computation of statutory restrictions on capital surplus.

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Regulatory and Capital Adequacy - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended	36 Months Ended
	Dec. 31, 2021	Dec. 31, 2025	Dec. 31, 2024
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Regulatory capital adjustments, net of tax, CECL transition	$ 2,400
Common equity tier one capital ratio, CECL transition			13.50%
Common equity tier one capital ratio, excluding CECL transition adjustment			13.30%
Forecast
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Regulatory capital adjustments, net of tax, CECL transition, phased in amount		$ 600
Capital One Bank (USA), N.A.
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Funds available for dividend payments			$ 8,900
Fund available for dividend payments, per share (in USD per share)			$ 0.60