REGULATORY CAPITAL MATTERS (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Parent Company [Member]
Total risk-based capital ratio
Amount	$ 619,804	$ 473,656
Ratio	12.56%	11.28%
Minimum Capital Requirement	$ 394,626	$ 335,829
Ratio	8.00%	8.00%
Tier 1 risk-based capital ratio
Amount	$ 594,795	$ 442,307
Ratio	12.06%	10.54%
Minimum Capital Requirement	$ 295,969	$ 167,914
Ratio	6.00%	4.00%
Common equity tier 1 capital ratio
Amount	$ 404,131
Ratio	8.19%
Minimum Capital Requirement	$ 221,977
Ratio	4.50%
Tier 1 leverage ratio
Amount	$ 594,795	$ 442,307
Ratio	8.97%	8.57%
Minimum Capital Requirement	$ 265,377	$ 206,502
Ratio	4.00%	4.00%
Banc Of California National Association [Member]
Total risk-based capital ratio
Amount	$ 734,134	$ 503,727
Ratio	14.93%	12.04%
Minimum Capital Requirement	$ 393,421	$ 334,834
Ratio	8.00%	8.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions	$ 491,776	$ 418,543
Ratio	10.00%	10.00%
Tier 1 risk-based capital ratio
Amount	$ 697,624	$ 472,378
Ratio	14.19%	11.29%
Minimum Capital Requirement	$ 295,066	$ 167,417
Ratio	6.00%	4.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions	$ 393,421	$ 251,126
Ratio	8.00%	6.00%
Common equity tier 1 capital ratio
Amount	$ 697,624
Ratio	14.19%
Minimum Capital Requirement	$ 221,299
Ratio	4.50%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions	$ 319,654
Ratio	6.50%
Tier 1 leverage ratio
Amount	$ 697,624	$ 472,378
Ratio	10.53%	9.17%
Minimum Capital Requirement	$ 265,049	$ 206,095
Ratio	4.00%	4.00%
Minimum Required to Be Well Capitalized Under Prompt Corrective Action Provisions	$ 331,312	$ 257,619
Ratio	5.00%	5.00%

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

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

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