Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 15,709us-gaap_ProfitLoss	$ 6,890us-gaap_ProfitLoss
Securities:
Net change in unrealized gain on securities	11,478	20,909
Reclassification adjustment for net gains realized in net income	(4,353)	(781)
Net change in non-credit related other than temporary impairment	24	24
Income taxes	(2,859)	(7,959)
Other comprehensive income on securities	4,290	12,193
Derivatives used in cash flow hedging relationships:
Net change in unrealized loss on derivatives	(1,454)us-gaap_UnrealizedGainLossOnDerivatives	(139)us-gaap_UnrealizedGainLossOnDerivatives
Reclassification adjustment for net loss on derivatives realized in net income	564	521
Income taxes	327	(142)
Other comprehensive income (loss) on cash flow hedges	(563)	240
Other comprehensive income	3,727	12,433
TOTAL COMPREHENSIVE INCOME	$ 19,436	$ 19,323

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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