Receivables (Details) (USD $)	3 Months Ended	6 Months Ended
	Jun. 30, 2014 Contract	Jun. 30, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables	$ 509,369,000	$ 509,369,000	$ 583,518,000
Number of Commercial Resupply Svcs contract missions	8
Number of Commercial Resupply Svcs Contract Missions Remaining	7
Percentage of Commercial Resupply Svcs Contract Launch Delivery	25.00%	25.00%
Revenue from Commercial Resupply Svcs contract inception to date	1,500,000,000	1,500,000,000
Contract value of Commercial Resupply Svcs contract	1,900,000,000	1,900,000,000
Period of performance criteria (in years)		15 years
Potential refund if performance criteria are not met	13,200,000	13,200,000
Billed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables	49,015,000	49,015,000	68,474,000
Unbilled [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables	460,354,000	460,354,000	515,044,000
Receivables pertaining to the commercial resupply services contract	249,000,000	249,000,000	335,000,000
Incentive fees due incrementally	$ 23,000,000	$ 23,000,000	$ 9,900,000
Period of incentive fees due (in years)	15 years