Securities (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 security	Dec. 31, 2013
Marketable Securities [Abstract]
Marketable securities, restricted, Total at cost	$ 110,006
Marketable securities, restricted, Total at FVM	108,087
Private-label collateralized mortgage obligations, amortized cost	4	5
Private-label collateralized mortgage obligations, fair value	4	5
Weighted average yields on tax-exempt obligations rate	34.00%
Number of securities in the portfolio with an unrealized loss for a period greater than 12 months	17
Maximum unrealized loss of as security for a period greater than 12 months	$ 1,431