Derivative Instruments (Details Textual) (USD $) In Thousands, unless otherwise specified	2 Months Ended	3 Months Ended				1 Months Ended
	Apr. 30, 2012 Derivative_Instrument	Mar. 31, 2014	Mar. 31, 2014 August 2012 Derivative_Instrument	Mar. 31, 2014 Designated as hedging instruments:	Mar. 31, 2013 Designated as hedging instruments:	May 31, 2010 August Two Thousand and Twelve Derivative_Instrument	Mar. 31, 2014 Interest rate contracts with corporate customers	Mar. 31, 2014 Offsetting interest rate contracts with other financial institutions	Mar. 31, 2014 Junior Subordinated Debt	Mar. 31, 2014 Interest rate swaps	Mar. 31, 2014 Commitments to fund fixed-rate residential mortgage loans	Dec. 31, 2013 Commitments to fund fixed-rate residential mortgage loans	Mar. 31, 2014 Commitments to sell residential mortgage loans	Dec. 31, 2013 Commitments to sell residential mortgage loans
Derivative Instruments (Textual) [Abstract]
Junior subordinated debentures						$ 75,000	$ 73,950	$ 73,950	$ 32,000	$ 30,000	$ 83,103	$ 54,807	$ 75,000	$ 50,000
Number of interest rate swap agreements (derivative instrument)	2
Variable interest rate of derivatives, description		the three-month LIBOR plus a pre-determined spread
Number of derivative instruments terminated (derivative instruments)			2			2
Derivative instruments deferred gain			1,679			1,679
Gains (losses) on derivative financial instruments				$ 0	$ 85