MERGERS AND ACQUISITIONS - Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Merger and conversion costs	$ 28,486	$ 1,102	$ 22,136
Professional fees paid for investment banking	5,487	4,556	3,943
Labor and related expenses	86,024	60,898	$ 51,342
NewBridge Bancorp
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Net interest income	255,403	253,737
Net income	74,272	60,512
Net income available to common shareholders	$ 74,272	$ 59,690
Basic income per common share (in dollars per share)	$ 1.36	$ 1.17
Diluted income per common share (in dollars per share)	$ 1.36	$ 1.16
Weighted average basic common shares outstanding (in shares)	54,666,023	51,216,107
Weighted average diluted common shares outstanding (in shares)	54,765,807	51,301,182
Merger and conversion costs	$ 19,315	$ 3,532
Professional fees paid for investment banking	7,807
Labor and related expenses	8,677
Facility and equipment related expense	5,167
Other miscellaneous expenses related to merger	$ 1,196