Investment in Securities (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Securities with gross unrealized losses aggregated by investment category and length of time
Total temporarily impaired securities, Less than 12 Months, Fair Value	$ 1,039	$ 13,838
Total temporarily impaired securities, Less than 12 Months, Unrealized Losses	1	73
Total temporarily impaired securities, Over 12 Months, Fair Value		965
Total temporarily impaired securities, Over 12 Months, Unrealized Losses		49
Corporate debt securities [Member]
Securities with gross unrealized losses aggregated by investment category and length of time
Total temporarily impaired securities, Less than 12 Months, Fair Value	1,039	7,039
Total temporarily impaired securities, Less than 12 Months, Unrealized Losses	1	25
U.S. government sponsored enterprise mortgage-backed securities [Member]
Securities with gross unrealized losses aggregated by investment category and length of time
Total temporarily impaired securities, Less than 12 Months, Fair Value		6,799
Total temporarily impaired securities, Less than 12 Months, Unrealized Losses		48
Total temporarily impaired securities, Over 12 Months, Fair Value		965
Total temporarily impaired securities, Over 12 Months, Unrealized Losses		$ 49