Restricted Stock Awards and Restricted Stock Units Description of Performance Incentive Plans (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restricted Stock Units [Member]
Schedule of Restricted Stock Award and Restricted Stock Unit Activity [Line Items]
Awards authorized and reserved under plan	0.4
Share Based Payment Expense for RSUs Expected to Vest	0.7
Restricted Stock Awards and Restricted Stock Units [Member]
Schedule of Restricted Stock Award and Restricted Stock Unit Activity [Line Items]
Awards authorized and reserved under plan		0.4	0.7
Vesting terms of RSUs and RSAs	Half of the these grants vest ratably on each of the first three anniversaries of the grant date; 25% will vest upon achievement of certain performance metrics; and the remaining 25% will vest one year from the date upon which certain performance metrics were achieved. If actual performance metrics exceed the targeted performance metrics by a predetermined amount, the executives are eligible to receive up to 200% of the performance-based portion of their award. Management has determined that the achievement of the performance benchmarks associated with the performance based RSUs granted in 2012 is probable and recorded $0.7 million in share-based payment expense related to	Half of the these grants vest ratably on each of the first three anniversaries of the grant date; 25% will vest upon achievement of certain performance metrics; and the remaining 25% will vest one year from the date upon which certain performance metrics were achieved. If actual performance metrics exceed the targeted performance metrics by a predetermined amount, the executives are eligible to receive up to 200% of the performance-based portion of their award. Management has determined that the achievement of the performance benchmarks associated with the performance based RSUs granted in 2012 is probable and recorded $0.7 million in share-based payment expense related to	Half of such grants vest ratably on each of the first four anniversaries of the grant date. The remaining half vest on a cliff basis on the fourth anniversary of the grant date, provided that certain corporate performance metrics are achieved. We have not recognized any share-based payment expense related to the performance