Investment Securities (Details 5) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Jun. 30, 2013	Jun. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Trust preferred securities	Dec. 31, 2012 Trust preferred securities	Dec. 31, 2011 Trust preferred securities
Losses recognized in earnings for trust preferred securities held
Beginning balance	$ 351	$ 261	$ 351	$ 261	$ 351	$ 261	$ 351	$ 261	$ 351	$ 10,674	$ 10,472
Reduction for debt securities for which other-than-temporary impairment has been previously recognized and there is no related other comprehensive income
Credit losses on debt securities for which other-than-temporary impairment has not been previously recognized									1,954
Additional credit losses on debt securities for which other-than-temporary impairment was previously recognized		90					1,954			171	202
Sale of debt securities										(10,494)
Ending balance							$ 2,305	$ 351	$ 2,305	$ 351	$ 10,674