REGULATORY CAPITAL MATTERS - Actual and Required Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Banc of California, NA
Total risk-based capital
Total risk-based capital ratio, actual amount	$ 1,195,050	$ 1,011,587
Total risk-based capital ratio, actual ratio (percent)	0.1571	0.1727
Total risk-based capital ratio, minimum capital requirements amount	$ 608,740	$ 468,698
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	$ 760,925	$ 585,873
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	$ 1,110,767	$ 938,346
Tier 1 risk-based capital ratio, actual ratio (percent)	0.1460	0.1602
Tier 1 risk-based capital ratio, minimum capital requirements amount	$ 456,555	$ 351,524
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	$ 608,740	$ 468,698
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	$ 1,110,767	$ 938,346
Common equity tier 1 capital ratio, actual ratio (percent)	0.1460	0.1602
Common equity tier 1 capital ratio, minimum capital requirements amount	$ 342,416	$ 263,643
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	$ 494,601	$ 380,817
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	$ 1,110,767	$ 938,346
Tier 1 leverage ratio, actual ratio (percent)	0.1206	0.1219
Tier 1 leverage ratio, minimum capital requirements amount	$ 368,306	$ 307,894
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	$ 460,382	$ 384,868
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	$ 1,140,480	$ 996,466
Total risk-based capital ratio, actual ratio (percent)	0.1498	0.1701
Total risk-based capital ratio, minimum capital requirements amount	$ 609,062	$ 468,628
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	$ 955,747	$ 840,501
Tier 1 risk-based capital ratio, actual ratio (percent)	0.1255	0.1435
Tier 1 risk-based capital ratio, minimum capital requirements amount	$ 456,796	$ 351,471
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	$ 860,841	$ 655,623
Common equity tier 1 capital ratio, actual ratio (percent)	0.1131	0.1119
Common equity tier 1 capital ratio, minimum capital requirements amount	$ 342,597	$ 263,603
Common equity tier 1 capital ratio, minimum capital requirements ratio (percent)	4.50%	4.50%
Tier 1 leverage
Tier 1 leverage ratio, actual amount	$ 955,747	$ 840,501
Tier 1 leverage ratio, actual ratio (percent)	0.1037	0.1090
Tier 1 leverage ratio, minimum capital requirements amount	$ 368,610	$ 308,555
Tier 1 leverage ratio, minimum capital requirements ratio (percent)	0.0400	0.0400

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