Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended		15 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Mar. 31, 2011
Amount Accrued
Beginning Balance			$ 3,335	$ 1,105
Accruals	473		2,230
Plan termination	(3,808)	0
Ending Balance	$ 0		$ 0	$ 1,105