INVESTMENTS IN DEBT AND EQUITY SECURITIES (Securities Held to Maturity) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Carrying value: Maturity, 1 Year or Less	$ 826	$ 1,372
Carrying value: Maturity, 1-5 Years	1,099	8,314
Carrying value: Maturity, 5-10 Years	161,254	982
Carrying value: Maturity, After 10 Years	468,374	2,149
Carrying value: Total Amortized Cost	631,553	12,817
Carrying value: Gross Unrealized Gains	6,462	607
Carrying value: Gross Unrealized Losses	(991)	0
Carrying value: Fair Value	637,024	13,424
Carrying value: Weighted Average Yield	1.80%	4.76%
Weighted average yield, Maturity, 1 Year or Less	2.56%	2.55%
Weighted average yield, Maturity, 1-5 Years	3.40%	4.67%
Weighted average yield, Maturity, 5-10 Years	1.77%	4.60%
Weighted average yield, Maturity, After 10 Years	1.81%	6.61%
U.S. Government sponsored agencies
Carrying value: Maturity, 1 Year or Less	0
Carrying value: Maturity, 1-5 Years	0
Carrying value: Maturity, 5-10 Years	52,582
Carrying value: Maturity, After 10 Years	0
Carrying value: Total Amortized Cost	52,582
Carrying value: Gross Unrealized Gains	269
Carrying value: Gross Unrealized Losses	0
Carrying value: Fair Value	52,851
Carrying value: Weighted Average Yield	1.63%
Residential mortgage-backed
Carrying value: Maturity, 1 Year or Less	0	0
Carrying value: Maturity, 1-5 Years	0	0
Carrying value: Maturity, 5-10 Years	108,420	728
Carrying value: Maturity, After 10 Years	466,863	615
Carrying value: Total Amortized Cost	575,283	1,343
Carrying value: Gross Unrealized Gains	6,142	116
Carrying value: Gross Unrealized Losses	(614)	0
Carrying value: Fair Value	580,811	1,459
Carrying value: Weighted Average Yield	1.82%	5.06%
Commercial mortgage-backed
Carrying value: Maturity, 1 Year or Less		0
Carrying value: Maturity, 1-5 Years		6,310
Carrying value: Maturity, 5-10 Years		0
Carrying value: Maturity, After 10 Years		0
Carrying value: Total Amortized Cost		6,310
Carrying value: Gross Unrealized Gains		447
Carrying value: Gross Unrealized Losses		0
Carrying value: Fair Value		6,757
Carrying value: Weighted Average Yield		5.16%
State and political subdivisions
Carrying value: Maturity, 1 Year or Less	826	1,372
Carrying value: Maturity, 1-5 Years	1,099	2,004
Carrying value: Maturity, 5-10 Years	252	254
Carrying value: Maturity, After 10 Years	1,511	1,534
Carrying value: Total Amortized Cost	3,688	5,164
Carrying value: Gross Unrealized Gains	51	44
Carrying value: Gross Unrealized Losses	(377)	0
Carrying value: Fair Value	3,362	5,208
Carrying value: Weighted Average Yield	1.89%	4.20%
Debt securities
Fair Value: Maturity, 1 Year or Less	836	1,387
Fair value: Maturity, 1-5 Years	1,129	8,768
Fair value: Maturity, 5-10 Years	164,433	1,056
Fair value: Maturity, After 10 Years	$ 470,626	$ 2,213

The percentage of held to maturity securities weighted average yield.

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The percentage of held to maturity securities weighted average yield, maturing in the fifth through tenth fiscal year following the latest fiscal year.

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The percentage of held to maturity securities weighted average yield, maturing in the next fiscal year through the fifth fiscal year following the latest fiscal year.

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The percentage of held to maturity securities weighted average yield, maturing after the tenth fiscal year following the latest fiscal year.

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The percentage of held to maturity securities weighted average yield, maturing in the next fiscal year following the latest fiscal year.

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Amount of investments in debt securities categorized as held-to-maturity valued at amortized cost, excludes other than temporary impairment (OTTI).

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Amount of held-to-maturity debt securities at fair value maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the fifth through tenth fiscal year following the latest fiscal year.

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Amount of held-to-maturity debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the next fiscal year through the fifth fiscal year following the latest fiscal year.

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Amount of held-to-maturity debt securities at fair value maturing after the tenth fiscal year following the latest fiscal year.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing after the tenth fiscal year following the latest fiscal year.

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Amount of held-to-maturity debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

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This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

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As of the balance sheet date, the excess of fair value over carrying value (amortized cost) of a debt security categorized as held-to-maturity, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding gain.

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As of the balance sheet date, the excess of carrying value (amortized cost) over fair value of a debt security categorized as held-to-maturity, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding loss.

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