Defined Contribution Retirement Plan
12 Months Ended
Dec. 31, 2011
Defined Contribution Retirement Plan [Abstract]  
Defined Contribution Retirement Plan

14.    Defined Contribution Retirement Plan

We have a defined contribution retirement plan (the “Retirement Plan”), the terms of which, as amended, allow eligible employees who have met certain age and service requirements to participate by electing to contribute a percentage of their compensation to be set aside to pay their future retirement benefits, as defined by the Retirement Plan. We have agreed to make discretionary contributions to the Retirement Plan. For the years ended December 31, 2011, 2010 and 2009, we made contributions to the Retirement Plan totaling approximately $0.07 million, $0.07 million and $0.06 million, respectively.