Dividend Availability and Regulatory Matters Dividend Availability and Regulatory Matters (Details) - USD ($)	Dec. 31, 2025	Dec. 31, 2024
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%
Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum	6.50%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%
Bank of California, inc.
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Leverage Capital	$ 3,331,161,000	$ 3,369,457,000
Tier One Leverage Capital to Average Assets	9.99%	10.15%
Tier One Leverage Capital Required to be Well Capitalized	$ 0	$ 0
Tier One Risk Based Common Equity	$ 2,701,645,000	$ 2,739,941,000
Common Equity Tier One Capital Ratio	10.01%	10.55%
Tier One Risk Based Common Equity Required to be Well Capitalized	$ 0	$ 0
Banking Regulation, Capital Conservation Buffer, Common Equity Tier 1 Risk-Based Capital, Actual		7.00%
Tier One Risk Based Capital	$ 3,331,161,000	$ 3,369,457,000
Tier One Risk Based Capital to Risk Weighted Assets	12.34%	12.97%
Tier One Risk Based Capital Required to be Well Capitalized	$ 1,619,857,000	$ 1,558,601,000
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets		6.00%
Banking Regulation, Capital Conservation Buffer, Tier 1 Risk-Based Capital, Actual		8.50%
Capital	$ 4,403,973,000	$ 4,427,860,000
Capital to Risk Weighted Assets	16.31%	17.05%
Capital Required to be Well Capitalized	$ 2,699,762,000	$ 2,597,668,000
Capital Required to be Well Capitalized to Risk Weighted Assets		10.00%
Banking Regulation, Capital Conservation Buffer, Total Risk-Based Capital, Actual		10.50%
Bank of California
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Leverage Capital	$ 3,543,771,000	$ 3,671,545,000
Tier One Leverage Capital to Average Assets	10.65%	11.08%
Tier One Leverage Capital Required to be Well Capitalized	$ 1,663,677,000	$ 1,656,718,000
Tier One Leverage Capital Required to be Well Capitalized to Average Assets		5.00%
Tier One Risk Based Common Equity	$ 3,543,771,000	$ 3,671,545,000
Common Equity Tier One Capital Ratio	13.15%	14.17%
Tier One Risk Based Common Equity Required to be Well Capitalized	$ 1,751,120,000	$ 1,684,283,000
Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum		6.50%
Banking Regulation, Capital Conservation Buffer, Common Equity Tier 1 Risk-Based Capital, Actual		7.00%
Tier One Risk Based Capital	$ 3,543,771,000	$ 3,671,545,000
Tier One Risk Based Capital to Risk Weighted Assets	13.15%	14.17%
Tier One Risk Based Capital Required to be Well Capitalized	$ 2,155,225,000	$ 2,072,963,000
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets		8.00%
Banking Regulation, Capital Conservation Buffer, Tier 1 Risk-Based Capital, Actual		8.50%
Capital	$ 4,206,727,000	$ 4,315,098,000
Capital to Risk Weighted Assets	15.61%	16.65%
Capital Required to be Well Capitalized	$ 2,694,031,000	$ 2,591,204,000
Capital Required to be Well Capitalized to Risk Weighted Assets		10.00%
Banking Regulation, Capital Conservation Buffer, Total Risk-Based Capital, Actual		10.50%

Tier One Risk Based Common Equity

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Tier One Risk Based Common Equity Required to be Well Capitalized

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Capital conservation buffer percentage calculated as Common Equity Tier 1 risk-based capital ratio after deduction of minimum Common Equity Tier 1 risk-based capital ratio as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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Capital conservation buffer percentage calculated as Tier 1 risk-based capital ratio after deduction of minimum Tier 1 risk-based capital ratio as defined by regulatory framework.

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Capital conservation buffer percentage calculated as total risk-based capital ratio after deduction of minimum total risk-based capital ratio as defined by regulatory framework.

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Amount of total capital as defined by regulatory framework.

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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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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

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-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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