REGULATORY CAPITAL MATTERS (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Banc of California, NA
Total risk-based capital
Amount	$ 1,141,916	$ 1,042,617
Ratio	16.39%	14.73%
Minimum Capital Requirement, Amount	$ 557,416	$ 566,405
Minimum Capital Requirement, Ratio	8.00%	8.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 696,770	$ 708,007
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%	10.00%
Tier 1 risk-based capital
Amount	$ 1,092,202	$ 999,788
Ratio	15.68%	14.12%
Minimum Capital Requirement, Amount	$ 418,062	$ 424,804
Minimum Capital Requirement, Ratio	6.00%	6.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 557,416	$ 566,405
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%	8.00%
Common equity tier 1 capital
Amount	$ 1,092,202	$ 999,788
Ratio	15.68%	14.12%
Minimum Capital Requirement, Amount	$ 313,546	$ 318,603
Minimum Capital Requirement, Ratio	4.50%	4.50%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 452,900	$ 460,204
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%	6.50%
Tier 1 leverage
Amount	$ 1,092,202	$ 999,788
Ratio	10.88%	8.71%
Minimum Capital Requirement, Amount	$ 401,584	$ 459,368
Minimum Capital Requirement, Ratio	4.00%	4.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 501,980	$ 574,210
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	$ 1,009,727	$ 975,918
Ratio	14.48%	13.70%
Minimum Capital Requirement, Amount	$ 557,714	$ 569,856
Minimum Capital Requirement, Ratio	8.00%	8.00%
Tier 1 risk-based capital
Amount	$ 960,013	$ 941,429
Ratio	13.77%	13.22%
Minimum Capital Requirement, Amount	$ 418,286	$ 427,392
Minimum Capital Requirement, Ratio	6.00%	6.00%
Common equity tier 1 capital
Amount	$ 690,942	$ 672,358
Ratio	9.91%	9.44%
Minimum Capital Requirement, Amount	$ 313,714	$ 320,544
Minimum Capital Requirement, Ratio	4.50%	4.50%
Tier 1 leverage
Amount	$ 960,013	$ 941,429
Ratio	9.55%	8.17%
Minimum Capital Requirement, Amount	$ 402,204	$ 460,840
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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