Investment securities HTM Contractual Maturity Table (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Amortized cost and fair values of investment securities held to maturity
Securities held to maturity, debt securities due in one year or less, amortized cost	$ 0
Securities held to maturity, debt securities due after one year through five years, amortized cost	230
Securities held to maturity, debt securities due after five years through ten years, amortized cost	82,187
Securities held to maturity, debt securities due after ten years, amortized cost	111,342
Total held to maturity debt securities, amortized Cost	193,759	175,210
Securities held to maturity, debt securities due in one year or less, fair value	0
Securities held to maturity, debt securities due in one year through five years, fair value	231
Securities held to maturity, debt securities due after five years through ten years, fair value	81,033
Securities held to maturity, debt securities due after ten years, fair value	111,882
Investment securities held to maturity, fair value	$ 193,146	$ 169,889
Ratio of Fair Value to Amortized Cost, HTM	99.70%