SECURITIES - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	May. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Proceeds from Sale of Available-for-sale Securities, Debt				$ 60,314,000	$ 16,444,000
Available-for-sale Securities, Gross Realized Gains				632,000	361,000
Available-for-sale Securities, Gross Realized Losses				$ 472,000
Collateral Underlying Mortgage Investments Terms				30- and 15-year fixed and 10/1 adjustable rate mortgage
Cost Method Investments, Fair Value Disclosure		$ 0		$ 0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		502,569,000		502,569,000		$ 527,682,000
Accumulated unrealized losses		(6,216,000)		(6,216,000)		(10,026,000)
Securities Available For Sale Transferred To Held-To-Maturity	$ 158,800,000
Available For Sale Securities Transferred To Held To Maturity Securities Unrealized Gain Loss	$ 3,100,000	0	$ 0	0	$ (3,137,000)
Trading Securities, Unrealized Holding Loss				2,400,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		260,146,000		260,146,000		301,040,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		2,241,000		2,241,000		3,672,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		242,423,000		242,423,000		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		3,975,000		3,975,000		0
Available-for-sale Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		10,300,000		10,300,000		11,600,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		27,000		27,000		$ 159,000
Mortgage Backed Securities And Collateralized Mortgage Obligations Of Us Government Sponsored Entities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities pledged as collateral		148,600,000		148,600,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		229,100,000		229,100,000
Accumulated unrealized losses		3,000,000		3,000,000
Collateralized Mortgage Backed Securities [Member] | Carrying Amount [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities pledged as collateral		125,000,000		125,000,000
Collateralized Mortgage Backed Securities [Member] | Fair Value [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities pledged as collateral		124,300,000		124,300,000
Collateralized Loan Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		134,600,000		134,600,000
Accumulated unrealized losses		1,500,000		1,500,000
Private Collateralized Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		105,700,000		105,700,000
Accumulated unrealized losses		$ 1,400,000		$ 1,400,000