Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Gain (Loss) on Sale of Securities, Net	$ 0	$ 18	$ 1	$ 28
Interest Expense, Junior Subordinated Debentures	(965)	(1,156)	(1,920)	(2,310)
Interest Expense, Deposits	(3,375)	(3,120)	(6,591)	(6,906)
Income tax expense	10,333	10,701	17,471	16,741
Net Income (Loss) Attributable to Parent	21,332	21,328	38,373	34,531
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(422)	(260)	(776)	(524)
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	0	18	1	28
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	0	8	0	12
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	0	10	1	16
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	(481)	(471)	(954)	(932)
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	(206)	(201)	(407)	(392)
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	(275)	(270)	(547)	(540)
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	(251)	0	(394)	0
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	(104)	0	(164)	0
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	$ (147)	$ 0	$ (230)	$ 0