INVESTMENTS IN DEBT AND EQUITY SECURITIES (Schedule of Continuous Unrealized Losses) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$ 191,970	$ 661,612
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(1,731)	(20,999)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	342,988	10,527
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(9,005)	(447)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	534,958	672,139
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(10,736)	(21,446)
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	217,833	566,896
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(1,811)	(19,441)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	284,068	10,253
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(9,640)	(315)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	501,901	577,149
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(11,451)	(19,756)
U.S. Government sponsored agencies [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	24,573	16,005
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(273)	(664)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	14,707	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(19)	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	39,280	16,005
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(292)	(664)
Residential mortgage-backed [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	179,472	511,617
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(1,076)	(18,119)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	259,445	5,473
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(9,537)	(95)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	438,917	517,090
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(10,613)	(18,214)
State and political subdivisions [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value		27,872
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses		(560)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		27,872
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses		(560)
Corporate notes [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	12,079	9,959
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(421)	(41)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	9,916	4,780
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(84)	(220)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	21,995	14,739
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(505)	(261)
Equity investments [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	1,709	1,443
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(41)	(57)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,709	1,443
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(41)	(57)
U.S. Government sponsored agencies [Member]
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	11,636	15,966
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(77)	(153)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	11,636	15,966
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(77)	(153)
Residential mortgage-backed [Member]
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	179,822	644,700
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(1,651)	(20,759)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	342,062	10,527
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(8,929)	(447)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	521,884	655,227
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	(10,580)	(21,206)
State and political subdivisions [Member]
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	512	946
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	(3)	(87)
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	926	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	(76)	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	1,438	946
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	$ (79)	$ (87)