Investments Maturities of AFS Securities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	$ 57,847
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis	299,251
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis	124,607
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	220,119
Investment securities available for sale at amortized cost	701,824	694,832
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	58,251
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	299,602
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	124,508
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	218,170
Available-for-sale Securities	$ 700,531	$ 691,729