ASSETS ACQUIRED IN FDIC-ASSISTED ACQUISITIONS - Narrative (Details) $ in Thousands	3 Months Ended					12 Months Ended		34 Months Ended
	Mar. 31, 2017	Sep. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2017 USD ($)	Dec. 31, 2012 USD ($)	Jul. 31, 2012 acquisition	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Number of FDIC-assisted acquisitions | acquisition								10
Reimbursement revenue							$ 87
Clawback liability						$ 10,000			$ 9,300
Single Family Residential Assets (SFR)
Business Acquisition [Line Items]
Coverage period for acquisitions						10 years
Non-Single Family Assets (NSF)
Business Acquisition [Line Items]
Coverage period for acquisitions						8 years
Coverage period for acquisitions, losses and recoveries both covered						5 years
Coverage period for acquisitions, only recoveries, net of expenses covered						3 years
American United Bank And United Security Bank | Non-Single Family Assets (NSF)
Business Acquisition [Line Items]
Anniversary mark for acquisition agreements					5 years
Satilla Community Bank (“SCB”) | Non-Single Family Assets (NSF)
Business Acquisition [Line Items]
Anniversary mark for acquisition agreements				5 years
First Bank Of Jacksonville, Tifton Banking Company, And Darby Bank & Trust | Non-Single Family Assets (NSF)
Business Acquisition [Line Items]
Anniversary mark for acquisition agreements			5 years
High Trust Bank And One Georgia Bank | Non-Single Family Assets (NSF)
Business Acquisition [Line Items]
Anniversary mark for acquisition agreements		5 years
Central Bank of Georgia (“CBG”) | Non-Single Family Assets (NSF)
Business Acquisition [Line Items]
Anniversary mark for acquisition agreements	5 years