SECURITIES (Details 4) $ in Thousands	Dec. 31, 2017 USD ($) holding	Dec. 31, 2016 USD ($) holding
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	163	121
Fair value, less than 12 months	$ 475,739	$ 444,471
Fair value, 12 months or longer	193,298	56,356
Fair value, Total	669,037	500,827
Unrealized losses, Total	(10,384)	(8,594)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(3,465)	(5,510)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	$ (6,919)	$ (3,084)
US Government Agencies Debt Securities [Member]
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	4
Fair value, less than 12 months	$ 24,343
Fair value, 12 months or longer	0
Fair value, Total	24,343
Unrealized losses, Total	(131)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	$ (131)
Agency mortgage-backed securities [Member]
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	84	57
Fair value, less than 12 months	$ 235,411	$ 137,949
Fair value, 12 months or longer	14,886	0
Fair value, Total	250,297	137,949
Unrealized losses, Total	(1,803)	(1,594)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(1,493)	(1,594)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	$ (310)	$ 0
Agency collateralized mortgage obligations [Member]
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	42	32
Fair value, less than 12 months	$ 178,142	$ 243,051
Fair value, 12 months or longer	159,506	47,403
Fair value, Total	337,648	290,454
Unrealized losses, Total	(7,151)	(5,129)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(1,579)	(3,140)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	$ (5,572)	$ (1,989)
Single issuer trust preferred securities issued by banks and insurers
Summary of gross unrealized losses and fair value of investments
No of holdings | holding		1
Fair value, less than 12 months		$ 0
Fair value, 12 months or longer		1,036
Fair value, Total		1,036
Unrealized losses, Total		(3)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months		0
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months		$ (3)
Pooled trust preferred securities issued by banks and insurers
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	1	1
Fair value, less than 12 months	$ 0	$ 0
Fair value, 12 months or longer	1,640	1,583
Fair value, Total	1,640	1,583
Unrealized losses, Total	(539)	(616)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	0	0
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	$ (539)	$ (616)
Small Business Administration Pooled Securities [Member]
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	4	5
Fair value, less than 12 months	$ 34,553	$ 59,846
Fair value, 12 months or longer	9,647	0
Fair value, Total	44,200	59,846
Unrealized losses, Total	(318)	(699)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(223)	$ (699)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	$ (95)
Marketable securities [Member]
Summary of gross unrealized losses and fair value of investments
No of holdings | holding	28	25
Fair value, less than 12 months	$ 3,290	$ 3,625
Fair value, 12 months or longer	7,619	6,334
Fair value, Total	10,909	9,959
Unrealized losses, Total	(442)	(553)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for less than 12 months	(39)	(77)
Unrealized loss position for available for sale and held to maturity securities in a continuous loss position for more than 12 months	$ (403)	$ (476)