INVESTMENT SECURITIES - Securities Transferred between AFS and HTM (Details) - USD ($)	3 Months Ended					9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Investment Securities
Securities classified as trading	$ 0					$ 0		$ 0
Securities transferred from available-for-sale to held-to-maturity category, remaining unamortized loss, net of tax	$ 820,000	$ (1,215,000)				(2,687,000)	$ (933,000)
Transferred From Available-For-Sale to Held-To-Maturity
Investment Securities
Securities transferred from available-for-sale to held-to-maturity category, amortized cost			$ 12,630,000	$ 152,890,000	$ 152,890,000
Securities transferred from available-for-sale to held-to-maturity category, fair value			12,640,000	147,450,000	147,450,000
Securities transferred from available-for-sale to held-to-maturity category, unrealized holding gain				$ 3,530,000	$ 3,530,000
Securities transferred from available-for-sale to held-to-maturity category, remaining unamortized loss						2,350,000
Securities transferred from available-for-sale to held-to-maturity category, remaining unamortized loss, net of tax						1,520,000
Unrealized Gains (Losses) on Securities | Transferred From Available-For-Sale to Held-To-Maturity
Investment Securities
Securities transferred from available-for-sale to held-to-maturity category, unrealized holding gain			$ 8,000
Securities transferred from available-for-sale to held-to-maturity category, remaining unamortized loss, net of tax						$ (779,000)	$ (396,000)