Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Gain (Loss) on Sale of Securities, Net	$ 8us-gaap_GainLossOnSaleOfSecuritiesNet	$ 1us-gaap_GainLossOnSaleOfSecuritiesNet
Interest Expense, Junior Subordinated Debentures	(956)	(955)
Interest Expense, Deposits	(3,892)us-gaap_InterestExpenseDeposits	(3,216)us-gaap_InterestExpenseDeposits
Income tax expense	8,572us-gaap_IncomeTaxExpenseBenefit	7,138us-gaap_IncomeTaxExpenseBenefit
Net Income (Loss) Attributable to Parent	18,783us-gaap_NetIncomeLoss	17,041us-gaap_NetIncomeLoss
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(586)	(354)
Reclassification Out of Accumulated Comprehensive Income, Pre-tax [Member] \| Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Gain (Loss) on Sale of Securities, Net	8	1
Reclassification Out of Accumulated Comprehensive Income, Tax effect [Member] \| Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income tax expense	3	0
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Accumulated Net Unrealized Investment Gain (Loss) [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net Income (Loss) Attributable to Parent	5	1
Hedges related to junior subordinated debt [Member] \| Reclassification Out of Accumulated Comprehensive Income, Pre-tax [Member] \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest Expense, Junior Subordinated Debentures	(471)	(473)
Hedges related to junior subordinated debt [Member] \| Reclassification Out of Accumulated Comprehensive Income, Tax effect [Member] \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income tax expense	(202)	(201)
Hedges related to junior subordinated debt [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member] \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net Income (Loss) Attributable to Parent	(269)	(272)
Hedges related to deposits [Member] \| Reclassification Out of Accumulated Comprehensive Income, Pre-tax [Member] \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest Expense, Deposits	(547)	(143)
Hedges related to deposits [Member] \| Reclassification Out of Accumulated Comprehensive Income, Tax effect [Member] \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income tax expense	(225)	(60)
Hedges related to deposits [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member] \| Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net Income (Loss) Attributable to Parent	$ (322)	$ (83)

The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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