LOANS (Change in accretable yield on acquired loans narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan and lease losses	$ 62,639		$ 61,963
Provision for loan losses	1,635	$ 4,263
2015, 2016 and 2017 Acquisitions
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contractually required payments of loans acquired	36,900
Estimated fair value of loans acquired	21,800
Allowance for loan and lease losses	64		$ 57
Provision for loan losses	7	$ 0
2015 Acquisitions | Non Impaired Purchased Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contractually required payments of loans acquired	3,670,000
Estimated fair value of loans acquired	$ 3,590,000