INVESTMENTS IN DEBT AND EQUITY SECURITIES (Securities Held to Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Carrying value: Maturity, 1 Year or Less	$ 640	$ 826
Carrying value: Maturity, 1-5 Years	16,902	1,099
Carrying value: Maturity, 5-10 Years	199,107	161,254
Carrying value: Maturity, After 10 Years	523,537	468,374
Carrying value: Total Amortized Cost	740,186	631,553
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	443	6,462
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	21,446	991
Carrying value: Fair Value	719,183	637,024
Carrying value: Weighted Average Yield	1.86%	1.80%
Weighted average yield, Maturity, 1 Year or Less	3.32%	2.56%
Weighted average yield, Maturity, 1-5 Years	2.20%	3.40%
Weighted average yield, Maturity, 5-10 Years	1.53%	1.77%
Weighted average yield, Maturity, After 10 Years	1.97%	1.81%
US Government sponsored agencies [Member]
Carrying value: Maturity, 1 Year or Less	0	0
Carrying value: Maturity, 1-5 Years	0	0
Carrying value: Maturity, 5-10 Years	16,119	52,582
Carrying value: Maturity, After 10 Years	0	0
Carrying value: Total Amortized Cost	16,119	52,582
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	0	269
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	153	0
Carrying value: Fair Value	15,966	52,851
Carrying value: Weighted Average Yield	1.14%	1.63%
Residential mortgage-backed [Member]
Carrying value: Maturity, 1 Year or Less	0	0
Carrying value: Maturity, 1-5 Years	16,327	0
Carrying value: Maturity, 5-10 Years	182,933	108,420
Carrying value: Maturity, After 10 Years	522,504	466,863
Carrying value: Total Amortized Cost	721,764	575,283
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	441	6,142
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	21,206	614
Carrying value: Fair Value	700,999	580,811
Carrying value: Weighted Average Yield	1.88%	1.82%
State and political subdivisions
Carrying value: Maturity, 1 Year or Less	640	826
Carrying value: Maturity, 1-5 Years	575	1,099
Carrying value: Maturity, 5-10 Years	55	252
Carrying value: Maturity, After 10 Years	1,033	1,511
Carrying value: Total Amortized Cost	2,303	3,688
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	2	51
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	87	377
Carrying value: Fair Value	2,218	3,362
Carrying value: Weighted Average Yield	1.93%	1.89%
Debt securities
Fair Value: Maturity, 1 Year or Less	642	836
Fair value: Maturity, 1-5 Years	16,926	1,129
Fair value: Maturity, 5-10 Years	195,647	164,433
Fair value: Maturity, After 10 Years	$ 505,968	$ 470,626