REGULATORY CAPITAL MATTERS - Actual and Required Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Banc of California, NA
Total risk-based capital
Total risk-based capital ratio, actual amount	$ 1,120,122	$ 1,131,057
Total risk-based capital ratio, actual ratio	15.71%	16.56%
Total risk-based capital ratio, minimum capital requirements amount	$ 570,382	$ 546,359
Total risk-based capital ratio, minimum capital requirements ratio	8.00%	8.00%
Total risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 712,977	$ 682,949
Total risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions ratio	10.00%	10.00%
Tier 1 risk-based capital
Tier 1 risk-based capital ratio, actual amount	$ 1,053,308	$ 1,078,008
Tier 1 risk-based capital ratio, actual ratio	14.77%	15.78%
Tier 1 risk-based capital ratio, minimum capital requirements amount	$ 427,786	$ 409,769
Tier 1 risk-based capital ratio, minimum capital requirements ratio	6.00%	6.00%
Tier 1 risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 570,382	$ 546,359
Tier 1 risk-based capital ratio, minimum required to be well capitalized under prompt corrective action provisions ratio	8.00%	8.00%
Common equity tier 1 capital
Common equity tier 1 capital ratio, actual amount	$ 1,053,308	$ 1,078,008
Common equity tier 1 capital ratio, actual ratio	14.77%	15.78%
Common equity tier 1 capital ratio, minimum capital requirements amount	$ 320,840	$ 307,327
Common equity tier 1 capital ratio, minimum capital requirements ratio	4.50%	4.50%
Common equity tier 1 capital ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 463,435	$ 443,917
Common equity tier 1 capital ratio, minimum required to be well capitalized under prompt corrective action provisions ratio	6.50%	6.50%
Tier 1 leverage
Tier 1 leverage ratio, actual amount	$ 1,053,308	$ 1,078,008
Tier 1 leverage ratio, actual ratio	10.36%	10.67%
Tier 1 leverage ratio, minimum capital requirements amount	$ 406,694	$ 404,060
Tier 1 leverage ratio, minimum capital requirements ratio	4.00%	4.00%
Tier 1 leverage ratio, minimum required to be well capitalized under prompt corrective action provisions amount	$ 508,368	$ 505,074
Tier 1 leverage ratio, minimum required to be well capitalized under prompt corrective action provisions ratio	5.00%	5.00%
Banc of California, Inc.
Total risk-based capital
Total risk-based capital ratio, actual amount	$ 977,342	$ 1,002,200
Total risk-based capital ratio, actual ratio	13.71%	14.56%
Total risk-based capital ratio, minimum capital requirements amount	$ 570,368	$ 550,499
Total risk-based capital ratio, minimum capital requirements ratio	8.00%	8.00%
Tier 1 risk-based capital
Tier 1 risk-based capital ratio, actual amount	$ 910,528	$ 949,151
Tier 1 risk-based capital ratio, actual ratio	12.77%	13.79%
Tier 1 risk-based capital ratio, minimum capital requirements amount	$ 427,776	$ 412,874
Tier 1 risk-based capital ratio, minimum capital requirements ratio	6.00%	6.00%
Common equity tier 1 capital
Common equity tier 1 capital ratio, actual amount	$ 679,400	$ 682,539
Common equity tier 1 capital ratio, actual ratio	9.53%	9.92%
Common equity tier 1 capital ratio, minimum capital requirements amount	$ 320,832	$ 309,656
Common equity tier 1 capital ratio, minimum capital requirements ratio	4.50%	4.50%
Tier 1 leverage
Tier 1 leverage ratio, actual amount	$ 910,528	$ 949,151
Tier 1 leverage ratio, actual ratio	8.95%	9.39%
Tier 1 leverage ratio, minimum capital requirements amount	$ 407,145	$ 404,339
Tier 1 leverage ratio, minimum capital requirements ratio	4.00%	4.00%

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Tier One Risk Based Common Capital Required for Capital Adequacy to Risk Weighted Assets

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The amount of total capital as defined in the regulations.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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Amount of Common Equity Tier One Risk-based Capital, as defined by regulatory framework.

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Amount of Common Equity Tier 1 Risk-based Capital required to be categorized as adequately capitalized under regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Risk Based Capital as defined in the regulations.

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