Retirement Plan (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Retirement Plan (Textual) [Abstract]
Employers' sponsors contribution retirement plan	90.00%
Contribution to retirement plan percentage of employee contribution	100.00%
Percentage of employee contribution to retirement plan	5.00%
Employers' sponsors contribution retirement plan amount	$ 0.1	$ 0.1	$ 0.1