Industry Segment Information (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011		Dec. 31, 2011
Segment Reporting Information [Line Items]
Revenues	$ 372,882,000		$ 342,170,000		$ 1,082,180,000		$ 1,010,472,000
Operating income	31,313,000		24,668,000		81,252,000		57,592,000
Identifiable assets	1,204,051,000				1,204,051,000				1,130,800,000	[1]
Capital expenditures	9,061,000		10,344,000		40,801,000		43,118,000
Depreciation and amortization	9,639,000		7,988,000		27,995,000		24,464,000
Intersegment revenues	17,500,000		27,700,000		49,900,000		82,800,000
Launch Vehicles [Member]
Segment Reporting Information [Line Items]
Revenues	140,673,000		116,538,000		393,135,000		353,178,000
Operating income	9,252,000		5,242,000		26,240,000		7,063,000
Identifiable assets	215,158,000				215,158,000				210,642,000	[1]
Capital expenditures	2,990,000		2,516,000		22,509,000		23,212,000
Depreciation and amortization	4,137,000		3,497,000		11,768,000		10,769,000
Intersegment revenues	15,900,000		26,100,000		44,900,000		77,800,000
Satelites and Space Systems [Member]
Segment Reporting Information [Line Items]
Revenues	129,490,000		141,130,000		370,887,000		431,963,000
Operating income	12,178,000		11,460,000		30,127,000		30,244,000
Identifiable assets	263,460,000				263,460,000				282,344,000	[1]
Capital expenditures	4,092,000		3,531,000		10,981,000		7,376,000
Depreciation and amortization	2,231,000		1,651,000		6,360,000		5,102,000
Intersegment revenues	1,400,000		1,500,000		4,400,000		3,900,000
Advanced Space Programs [Member]
Segment Reporting Information [Line Items]
Revenues	120,193,000		112,214,000		368,103,000		308,112,000
Operating income	9,883,000		7,966,000		26,976,000		20,285,000
Identifiable assets	390,892,000				390,892,000				254,769,000	[1]
Capital expenditures	1,142,000		3,098,000		4,558,000		10,294,000
Depreciation and amortization	1,677,000		1,276,000		5,130,000		3,576,000
Intersegment revenues	200,000		100,000		600,000		1,100,000
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Revenues	(17,474,000)	[2]	(27,712,000)	[2]	(49,945,000)	[2]	(82,781,000)	[2]
Operating income	0		0		(2,091,000)	[3]	0
Identifiable assets	334,541,000				334,541,000				383,045,000	[1]
Capital expenditures	837,000		1,199,000		2,753,000		2,236,000
Depreciation and amortization	$ 1,594,000		$ 1,564,000		$ 4,737,000		$ 5,017,000

[1] As of December 31, 2011.

[2] Corporate and other revenues are comprised solely of the elimination of intersegment revenues summarized as follows (in millions): Launch vehicles Quarters Ended September 30, 2012 2011 15.9 26.1 Nine Months Ended September 30,2012 2011 44.9 77.8 Satellites and Space Systems Quarters Ended September 30, 2012 2011 1.4 1.5 Nine Months Ended September 30, 2012 2011 4.4 3.9 Advanced Space Programs Quarters Ended September 30, 2012 2011 0.2 0.1 Nine Months Ended September 30, 2012 2011 0.6 1.1 Total intersegment revenues Quarters Ended September 30, 2012 2011 17.5 27.7 Nine Months Ended September 30, 2012 2011 49.9 82.8

[3] The corporate and other operating loss in 2012 is comprised solely of professional fees and other costs related to a potential acquisition that was not consummated.