REGULATORY CAPITAL MATTERS - Actual and Required Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Banc of California, NA
Total risk-based capital
Total risk-based capital ratio, actual amount	$ 1,201,884	$ 1,195,050
Total risk-based capital ratio, actual ratio (percent)	0.1602	0.1571
Total risk-based capital ratio, minimum capital requirements amount	$ 600,116	$ 608,740
Total risk-based capital ratio, minimum capital requirements ratio (percent)	0.0800	0.0800
Total risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 750,145	$ 760,925
Total risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions ratio (percent)	0.1000	0.1000
Tier 1 risk-based capital
Tier 1 risk-based capital ratio, actual amount	$ 1,121,049	$ 1,110,767
Tier 1 risk-based capital ratio, actual ratio (percent)	0.1494	0.1460
Tier 1 risk-based capital ratio, minimum capital requirements amount	$ 450,087	$ 456,555
Tier 1 risk-based capital ratio, minimum capital requirements ratio (percent)	0.0600	0.0600
Tier 1 risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 600,116	$ 608,740
Tier 1 risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions ratio (percent)	0.0800	0.0800
Common equity tier 1 capital
Common equity tier 1 capital ratio, actual amount	$ 1,121,049	$ 1,110,767
Common equity tier 1 capital ratio, actual ratio (percent)	0.1494	0.1460
Common equity tier 1 capital ratio, minimum capital requirements amount	$ 337,565	$ 342,416
Common equity tier 1 capital ratio, minimum capital requirements ratio (percent)	4.50%	4.50%
Common equity tier 1 capital ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 487,594	$ 494,601
Common equity tier 1 capital ratio, minimum required to be well capitalized under prompt corrective action provisions ratio (percent)	6.50%	6.50%
Tier 1 leverage
Tier 1 leverage ratio, actual amount	$ 1,121,049	$ 1,110,767
Tier 1 leverage ratio, actual ratio (percent)	0.1225	0.1206
Tier 1 leverage ratio, minimum capital requirements amount	$ 365,989	$ 368,306
Tier 1 leverage ratio, minimum capital requirements ratio (percent)	0.0400	0.0400
Tier 1 leverage ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 457,486	$ 460,382
Tier 1 leverage ratio, minimum required to be well capitalized under prompt corrective action provisions ratio (percent)	0.0500	0.0500
Banc of California, Inc.
Total risk-based capital
Total risk-based capital ratio, actual amount	$ 1,069,180	$ 1,140,480
Total risk-based capital ratio, actual ratio (percent)	0.1421	0.1498
Total risk-based capital ratio, minimum capital requirements amount	$ 601,941	$ 609,062
Total risk-based capital ratio, minimum capital requirements ratio (percent)	0.0800	0.0800
Tier 1 risk-based capital
Tier 1 risk-based capital ratio, actual amount	$ 887,717	$ 955,747
Tier 1 risk-based capital ratio, actual ratio (percent)	0.1180	0.1255
Tier 1 risk-based capital ratio, minimum capital requirements amount	$ 451,456	$ 456,796
Tier 1 risk-based capital ratio, minimum capital requirements ratio (percent)	0.0600	0.0600
Common equity tier 1 capital
Common equity tier 1 capital ratio, actual amount	$ 887,717	$ 860,841
Common equity tier 1 capital ratio, actual ratio (percent)	0.1180	0.1131
Common equity tier 1 capital ratio, minimum capital requirements amount	$ 338,592	$ 342,597
Common equity tier 1 capital ratio, minimum capital requirements ratio (percent)	4.50%	4.50%
Tier 1 leverage
Tier 1 leverage ratio, actual amount	$ 887,717	$ 955,747
Tier 1 leverage ratio, actual ratio (percent)	0.0970	0.1037
Tier 1 leverage ratio, minimum capital requirements amount	$ 365,892	$ 368,610
Tier 1 leverage ratio, minimum capital requirements ratio (percent)	0.0400	0.0400

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