Commitments and Contingencies (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Aggregate minimum commitments under non-cancelable operating leases [Abstract]
2014	$ 18,670,000
2015	18,604,000
2016	17,765,000
2017	15,049,000
2018	16,992,000
Thereafter	42,070,000
Total minimum commitments due	129,150,000
Rent expense	19,400,000	19,700,000	19,300,000
Research and development allowable costs reported as allowable expenses inception to date.		177,000,000
Write off option payment	10,000,000
Revenue Of Commercial Resupply Svsitd	$ 1,300,000,000
Percentage of Commercial and Resupply Services Contract that is launch and delivery milestones	25.00%