Investment Securities (Details 2) (USD $)	3 Months Ended					3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 OTTI Related to Credit Loss	Mar. 31, 2012 OTTI Related to Credit Loss	Dec. 31, 2011 OTTI Related to Credit Loss	Mar. 31, 2013 OTTI Related to All Other Factors	Mar. 31, 2012 OTTI Related to All Other Factors	Mar. 31, 2013 PMBS item	Dec. 31, 2012 PMBS
Other than Temporary Impairment
Number of investment securities in which other than temporary impairment losses were recognized								2
Other than temporary impairment investments, fair value									$ 700,000
Other than temporary impairment investments, historical cost									1,000,000
Additional information related to the recognized OTTI losses
Balance, beginning of the period	279,000	470,000	109,000	109,000	109,000	170,000	361,000
Less: losses related to OTTI securities sold	(279,000)		(109,000)			(170,000)
Change in value attributable to other factors		(38,000)					(38,000)
Balance, end of the period		$ 432,000		$ 109,000	$ 109,000		$ 323,000