Balance Sheet Accounts and Supplemental Disclosures (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Receivables [Abstract]
Receivables, net	$ 333,467,000	$ 326,543,000
Period of performance criteria (in years)	15Y
Potential refund if performance criteria are not met	14,100,000
Inventory [Abstract]
Inventories	64,335,000	56,217,000
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	447,155,000	392,148,000
Accumulated depreciation and amortization	(187,183,000)	(159,442,000)
Property, plant and equipment, net	259,972,000	232,706,000
Depreciation expense	32,000,000	25,700,000	19,200,000
Goodwill [Roll Forward]
Balance at beginning of period	74,747,000
Goodwill adjustment	514,000
Balance at end of period	75,261,000	74,747,000
Accrued expenses [Abstract]
Contract related accruals	142,735,000	150,831,000
Payroll related accruals	64,321,000	60,997,000
Interest	1,946,000	1,627,000
Other	11,933,000	15,452,000
Total	220,935,000	228,907,000
Cash flow supplemental financial information [Abstract]
Interest paid	4,158,000	3,735,000	3,741,000
Income taxes paid	2,242,000	2,531,000	1,309,000
Acquired Technology [Member]
Intangible assets [Abstract]
Intangible assets, net	5,900,000	6,600,000
Amortization expense	700,000	500,000
Launch Vehicles [Member]
Goodwill [Roll Forward]
Balance at end of period	10,310,000	10,310,000
Satellites and Space Systems [Member]
Goodwill [Roll Forward]
Balance at beginning of period	53,301,000
Goodwill adjustment	216,000
Balance at end of period	53,517,000
Advanced Space Programs [Member]
Goodwill [Roll Forward]
Balance at beginning of period	11,136,000
Goodwill adjustment	298,000
Balance at end of period	11,434,000
Land [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	10,656,000	9,113,000
Buildings and Leasehold Improvements [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	80,885,000	78,534,000
Furniture, Fixtures and Equipment [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	262,906,000	215,623,000
Assets under Construction [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	65,645,000	65,087,000
Software and Other [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	27,063,000	23,791,000
Billed [Member]
Receivables [Abstract]
Receivables, net	77,505,000	56,035,000
Unbilled [Member]
Receivables [Abstract]
Retainages due upon contract completion	753,000	1,672,000
Receivables, net	255,209,000	268,836,000
Percentage of unbilled receivables and retainages due within one year (in hundredths)	95.00%
Incentive fees due incrementally	$ 10,200,000	$ 14,900,000
Period of incentive fees due (in years)	15Y