SECURITIES (Schedule of Unrealized Gross Losses and Estimated Fair values of Investment Securities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Fair Value - Less Than 12 Months	$ 335,786	$ 386,967
Unrealized Losses - Less Than 12 Months	(8,664)	(11,942)
Fair Value - 12 Months of More	146,583	122,236
Unrealized Losses - 12 Months or More	(8,365)	(7,834)
Fair Value	482,369	509,203
Unrealized losses	(17,029)	(19,776)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	3,183
Held to Maturity Securities Unrealized Loss Position Less Than 12 Months Aggregate Losses Accumulated in Investments	(35)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	3,183
Held to Maturity Securities Gross Unrealized Loss Accumulated in Investments	(35)
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value - Less Than 12 Months	631	2,143
Unrealized Losses - Less Than 12 Months	(2)	(11)
Fair Value - 12 Months of More	0	0
Unrealized Losses - 12 Months or More	0	0
Fair Value	631	2,143
Unrealized losses	(2)	(11)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	3,183
Held to Maturity Securities Unrealized Loss Position Less Than 12 Months Aggregate Losses Accumulated in Investments	(35)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	3,183
Held to Maturity Securities Gross Unrealized Loss Accumulated in Investments	(35)
US Government-sponsored Enterprises Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value - Less Than 12 Months	131,887	145,424
Unrealized Losses - Less Than 12 Months	(2,760)	(4,189)
Fair Value - 12 Months of More	43,244	43,915
Unrealized Losses - 12 Months or More	(2,280)	(2,845)
Fair Value	175,131	189,339
Unrealized losses	(5,040)	(7,034)
Collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Fair Value - Less Than 12 Months	202,801	239,278
Unrealized Losses - Less Than 12 Months	(5,901)	(7,738)
Fair Value - 12 Months of More	98,773	73,376
Unrealized Losses - 12 Months or More	(5,712)	(4,586)
Fair Value	301,574	312,654
Unrealized losses	(11,613)	(12,324)
Private issue collateralized mortgage obligations
Schedule of Available-for-sale Securities [Line Items]
Fair Value - Less Than 12 Months	467	122
Unrealized Losses - Less Than 12 Months	(1)	(4)
Fair Value - 12 Months of More	4,566	4,945
Unrealized Losses - 12 Months or More	(373)	(403)
Fair Value	5,033	5,067
Unrealized losses	$ (374)	$ (407)