SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE AND OTHER SHORT-TERM DEBT - Information Regarding Other Borrowed Funds (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Borrowed Funds
Amount outstanding at year end	$ 312,118	$ 286,639
FHLB short-term borrowings
Other Borrowed Funds
Amount outstanding at year end	40,000
Maximum amount outstanding during the year	110,000	63,000	$ 18,900
Average amount outstanding during the year	$ 25,425	$ 3,953	$ 212
Weighted average-rate during the year	0.48%	0.33%	0.31%
Weighted average rate at year-end	0.77%
Securities sold under agreement to repurchase
Other Borrowed Funds
Amount outstanding at year end	$ 312,118	$ 286,639	$ 258,464
Maximum amount outstanding during the year	334,023	318,788	292,692
Average amount outstanding during the year	$ 247,610	$ 226,913	$ 192,868
Weighted average-rate during the year	0.18%	0.22%	0.18%
Weighted average rate at year-end	0.20%	0.19%	0.26%