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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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