REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	$ 18,287	$ 18,505	$ 56,771	$ 51,735
Loan servicing income	821	1,670	3,888	5,231
Securities gains/(losses), net	2,013	(145)	7,168	1,037
Unrealized gain on equity securities, net	144	54	514	97
Net gains on sale of loans held for sale	4,673	7,410	12,192	18,261
Valuation adjustment on servicing rights	(626)	230	(1,579)	12
Income on bank owned life insurance	881	892	2,668	2,206
Other noninterest income	3,207	1,149	6,556	3,536
Total noninterest income out-of-scope of Topic 606	11,113	11,260	31,407	30,380
TOTAL NONINTEREST INCOME	29,400	29,765	88,178	82,115
Service charges and fees on deposit accounts
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	3,221	2,858	9,383	8,270
Overdraft fees
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	2,917	2,990	8,537	7,716
Customer service and other service fees
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	104	102	270	268
Credit card fee income
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	3,936	3,062	11,555	8,443
Debit card income
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	2,188	3,883	10,044	10,349
Total service charges and fees
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	12,366	12,895	39,789	35,046
Trust fees
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	4,959	4,499	14,258	13,794
Brokerage and insurance commissions
Disaggregation of Revenue [Line Items]
Service charges and fees on deposit accounts	$ 962	$ 1,111	$ 2,724	$ 2,895