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ACQUISITIONS - FIRST CHOICE NARRATIVE (Details) |  | 12 Months Ended
--- | --- | ---
Dec. 02, 2016 USD ($) branch $ / shares shares | Dec. 31, 2016 USD ($) shares | Dec. 31, 2015 USD ($) shares
Business Acquisition [Line Items] |  |  |
Common stock, shares outstanding (shares) |  | 35,672,817 | 30,973,986
First Choice Bank |  |  |
Business Acquisition [Line Items] |  |  |
Number of retail bank branches acquired (branch) | branch | 8 |  |
Preferred stock outstanding (shares) | 51,000 |  |
Share price (USD per share) | $ / shares | $ 34.25 |  |
Total consideration paid | $ | $ 151,048,000 |  |
Acquisition related costs | $ |  | $ 11,900,000 | $ 0
First Choice Bank | Common Stock for Common Stock |  |  |
Business Acquisition [Line Items] |  |  |
Business acquisition, equity interest issued (shares) | 1,945,000 |  |
First Choice Bank | Common stock |  |  |
Business Acquisition [Line Items] |  |  |
Business acquisition, equity interest issued (shares) | 4,410,000.000 |  |
First Choice Bank | Series A Preferred Stock for Common Stock |  |  |
Business Acquisition [Line Items] |  |  |
Conversion ratio | 57.7300 |  |
First Choice Bank | Series B Preferred Stock for Common Stock |  |  |
Business Acquisition [Line Items] |  |  |
Conversion ratio | 57.7300 |  |
First Choice Bank | Series C Preferred Stock for Common Stock |  |  |
Business Acquisition [Line Items] |  |  |
Conversion ratio | 50.0694 |  |
First Choice Bank | Series D Preferred Stock for Common Stock |  |  |
Business Acquisition [Line Items] |  |  |
Conversion ratio | 41.2357 |  |
First Choice Bank | Series E Preferred Stock for Common Stock |  |  |
Business Acquisition [Line Items] |  |  |
Conversion ratio | 36.3082 |  |
First Choice Bank | Common stock |  |  |
Business Acquisition [Line Items] |  |  |
Conversion ratio | 0.5773 |  |
First Choice Bank | Series A Preferred Stock |  |  |
Business Acquisition [Line Items] |  |  |
Preferred stock outstanding (shares) | 7,500 |  |
First Choice Bank | Series B Preferred Stock |  |  |
Business Acquisition [Line Items] |  |  |
Preferred stock outstanding (shares) | 15,000 |  |
First Choice Bank | Series C Preferred Stock |  |  |
Business Acquisition [Line Items] |  |  |
Preferred stock outstanding (shares) | 6,000 |  |
First Choice Bank | Series D Preferred Stock |  |  |
Business Acquisition [Line Items] |  |  |
Preferred stock outstanding (shares) | 10,000 |  |
First Choice Bank | Series E Preferred Stock |  |  |
Business Acquisition [Line Items] |  |  |
Preferred stock outstanding (shares) | 12,500 |  |
First Choice Bank |  |  |
Business Acquisition [Line Items] |  |  |
Excess amount per share in which cash payment was due in lieu of fraction shares (USD per share) | $ / shares | $ 16.00 |  |
First Choice Bank | First Choice Bank | Common stock |  |  |
Business Acquisition [Line Items] |  |  |
Common stock, shares outstanding (shares) | 3,369,000.000 |  |

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