SECURITIES - Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	$ 209,047	$ 207,904
Held for Investment, Fair Value, Total	212,362	208,788
Available for Sale, Amortized Cost, Total	729,465
Available for Sale, Fair Value, Total	728,161	741,375
Collateralized Loan Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Due in less than one year	0
Held for Investment, Fair Value, Due in less than one year	0
Available for Sale Amortized Cost, Due in less than one year	225
Available for Sale, Fair Value, Due in less than one year	225
Held for Investment, Amortized Cost, Due after one year through five years	0
Held for Investment, Fair Value, Due after one year through five years	0
Available for Sale, Amortized Cost, Due after one year through five years	42,560
Available for Sale, Fair Value, Due after one year through five years	42,307
Held for Investment, Amortized Cost, Due after five years through ten years	41,300
Held for Investment, Fair Value, Due after five years through ten years	40,946
Available for Sale, Amortized Cost, Due after five years through ten years	106,746
Available for Sale, Fair Value, Due after five years through ten years	106,247
Held for Investment, Amortized Cost, Due after ten years	0
Held for Investment, Fair Value, Due after ten years	0
Available for Sale, Amortized Cost, Due after ten years	11,042
Available for Sale, Fair Value, Due after ten years	11,634
Held for Investment, Amortized Cost, Total	41,300
Held for Investment, Fair Value, Total	40,946
Available for Sale, Amortized Cost, Total	160,573
Available for Sale, Fair Value, Total	160,413
Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	65,787
Held for Investment, Fair Value, Total	67,913	68,347
Available for Sale, Amortized Cost, Total	117,458
Available for Sale, Fair Value, Total	118,492	125,059
Collateralized Mortgage Obligations Of US Government Sponsored Entities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	93,646
Held for Investment, Fair Value, Total	95,271	114,956
Available for Sale, Amortized Cost, Total	257,486
Available for Sale, Fair Value, Total	255,907	347,481
Private mortgage backed securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	0
Held for Investment, Fair Value, Total	0
Available for Sale, Amortized Cost, Total	32,494
Available for Sale, Fair Value, Total	32,216	30,258
Private collateralized mortgage obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	8,314
Held for Investment, Fair Value, Total	8,232
Available for Sale, Amortized Cost, Total	82,183
Available for Sale, Fair Value, Total	82,188	$ 85,135
Corporate and other debt securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	0
Held for Investment, Fair Value, Total	0
Available for Sale, Amortized Cost, Total	40,015
Available for Sale, Fair Value, Total	39,918
Private commercial mortgage backed securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held for Investment, Amortized Cost, Total	0
Held for Investment, Fair Value, Total	0
Available for Sale, Amortized Cost, Total	39,256
Available for Sale, Fair Value, Total	$ 39,027