INVESTMENTS IN DEBT AND EQUITY SECURITIES - (Securities Held to Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	$ 445	$ 640
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	80,410	16,902
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	129,512	199,107
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	508,305	523,537
Held-to-maturity Securities, Amortized Cost Before Other Than Temporary Impairment	718,672	740,186
Held-to-maturity Securities, Gross Unrealized Gains	623	443
Held-to-maturity Securities, Gross Unrealized Losses	(14,318)	(21,446)
Held-to-maturity Securities, Fair Value	704,977	719,183
Held-to-maturity Securities Weighted Average Yield	1.89%	1.86%
Held-to-maturity Securities Weighted Average Yield With In One Year	2.85%	3.32%
Held-to-maturity Securities Weighted Average Yield After One Through Five Years	2.01%	2.20%
Held-to-maturity Securities Weighted Average Yield After Five Through Ten Years	1.42%	1.53%
Held-to-maturity Securities Weighted Average Yield After Ten Years	2.00%	1.97%
U.S. Government sponsored agencies [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	0	0
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	0	0
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	14,373	16,119
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	0	0
Held-to-maturity Securities, Amortized Cost Before Other Than Temporary Impairment	14,373	16,119
Held-to-maturity Securities, Gross Unrealized Gains	0	0
Held-to-maturity Securities, Gross Unrealized Losses	(135)	(153)
Held-to-maturity Securities, Fair Value	14,238	15,966
Held-to-maturity Securities Weighted Average Yield	1.16%	1.14%
Residential mortgage-backed [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	0	0
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	79,836	16,327
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	115,139	182,933
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	507,272	522,504
Held-to-maturity Securities, Amortized Cost Before Other Than Temporary Impairment	702,247	721,764
Held-to-maturity Securities, Gross Unrealized Gains	622	441
Held-to-maturity Securities, Gross Unrealized Losses	(14,101)	(21,206)
Held-to-maturity Securities, Fair Value	688,768	700,999
Held-to-maturity Securities Weighted Average Yield	1.91%	1.88%
State and political subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	445	640
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	574	575
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	0	55
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	1,033	1,033
Held-to-maturity Securities, Amortized Cost Before Other Than Temporary Impairment	2,052	2,303
Held-to-maturity Securities, Gross Unrealized Gains	1	2
Held-to-maturity Securities, Gross Unrealized Losses	(82)	(87)
Held-to-maturity Securities, Fair Value	1,971	2,218
Held-to-maturity Securities Weighted Average Yield	1.63%	1.93%
Debt securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Fair Value	445	642
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Fair Value	80,347	16,926
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Fair Value	128,038	195,647
Held-to-maturity Securities, Debt Maturities, After Ten Years, Fair Value	$ 496,147	$ 505,968