REGULATORY CAPITAL MATTERS (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Banc of California, NA
Total risk-based capital
Amount	$ 1,128,784	$ 1,131,057
Ratio	16.53%	16.56%
Minimum Capital Requirement, Amount	$ 546,256	$ 546,359
Minimum Capital Requirement, Ratio	8.00%	8.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 682,820	$ 682,949
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%	10.00%
Tier 1 risk-based capital
Amount	$ 1,069,728	$ 1,078,008
Ratio	15.67%	15.78%
Minimum Capital Requirement, Amount	$ 409,692	$ 409,769
Minimum Capital Requirement, Ratio	6.00%	6.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 546,256	$ 546,359
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%	8.00%
Common equity tier 1 capital
Amount	$ 1,069,728	$ 1,078,008
Ratio	15.67%	15.78%
Minimum Capital Requirement, Amount	$ 307,269	$ 307,327
Minimum Capital Requirement, Ratio	4.50%	4.50%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 443,833	$ 443,917
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%	6.50%
Tier 1 leverage
Amount	$ 1,069,728	$ 1,078,008
Ratio	10.50%	10.67%
Minimum Capital Requirement, Amount	$ 407,428	$ 404,060
Minimum Capital Requirement, Ratio	4.00%	4.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 509,285	$ 505,074
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%	5.00%
Banc of California, Inc.
Total risk-based capital
Amount	$ 998,423	$ 1,002,200
Ratio	14.60%	14.56%
Minimum Capital Requirement, Amount	$ 547,082	$ 550,499
Minimum Capital Requirement, Ratio	8.00%	8.00%
Tier 1 risk-based capital
Amount	$ 939,367	$ 949,151
Ratio	13.74%	13.79%
Minimum Capital Requirement, Amount	$ 410,311	$ 412,874
Minimum Capital Requirement, Ratio	6.00%	6.00%
Common equity tier 1 capital
Amount	$ 670,296	$ 682,539
Ratio	9.80%	9.92%
Minimum Capital Requirement, Amount	$ 307,733	$ 309,656
Minimum Capital Requirement, Ratio	4.50%	4.50%
Tier 1 leverage
Amount	$ 939,367	$ 949,151
Ratio	9.21%	9.39%
Minimum Capital Requirement, Amount	$ 407,892	$ 404,339
Minimum Capital Requirement, Ratio	4.00%	4.00%

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Tier One Risk Based Common Capital

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Tier One Risk Based Common Capital Required for Capital Adequacy

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

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Tier One Risk Based Common Capital Required to be Well Capitalized

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Tier One Risk Based Common Capital Required to be Well Capitalized to Risk Weighted Assets

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Tier One Risk Based Common Capital to Risk Weighted Assets

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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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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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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