Business and Summary of Significant Accounting Policies (Details) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended										12 Months Ended										12 Months Ended
	Dec. 31, 2013 USD ($) FinancialInstitutions		Sep. 30, 2013 USD ($)	Jun. 30, 2013 USD ($)	Mar. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)		Sep. 30, 2012 USD ($)	Jun. 30, 2012 USD ($)	Mar. 31, 2012 USD ($)	Dec. 31, 2013 USD ($) FinancialInstitutions		Dec. 31, 2012 USD ($)		Dec. 31, 2011 USD ($)		Dec. 31, 2013 Forward Contracts [Member] USD ($)	Dec. 31, 2013 Forward Contracts [Member] EUR (€)	Dec. 31, 2012 Forward Contracts [Member] USD ($)	Dec. 31, 2012 Forward Contracts [Member] EUR (€)	Dec. 31, 2013 COTS Agreement - Cost-Sharing Arrangement Terms with NASA [Member] USD ($)	Dec. 31, 2013 Antares Development Program [Member] USD ($)	Dec. 31, 2012 Antares Development Program [Member] USD ($)	Dec. 31, 2011 Antares Development Program [Member] USD ($)	Dec. 31, 2013 Buildings [Member]	Dec. 31, 2013 Machinery, Equipment and Software [Member] Minimum [Member]	Dec. 31, 2013 Machinery, Equipment and Software [Member] Maximum [Member]	Dec. 31, 2013 Leasehold Improvements [Member]
Business and Summary of Significant Accounting Policies [Abstract]
Aggregate Net Changes in Contract Estimates Increased (Decreased) Operating Income.											$ 59,000,000		$ 61,000,000		$ (1,000,000)
Property, Plant and Equipment [Line Items]
Useful life (in years)																									20 years	3 years	12 years
Useful life, description																												Shorter of estimated useful life or lease term
Numerator
Net income	16,933,000	[1]	15,552,000	16,279,000	19,602,000	13,947,000	[2]	19,452,000	14,614,000	12,993,000	68,366,000		61,006,000		67,394,000
Percentage allocated to shareholders (in hundredths)											99.80%	[3]	99.60%	[3]	99.10%	[3]
Numerator for basic and diluted earnings per share											68,229,000		60,762,000		66,787,000
Denominator
Denominator for basic earnings per share - weighted-average shares outstanding (in shares)											60,161		59,165		58,531
Dilutive effect of stock options and restricted stock units (in shares)											283		292		596
Denominator for diluted earnings per share (in shares)											60,444		59,457		59,127
Per share income
Basic (in dollars per share)	$ 0.28		$ 0.26	$ 0.27	$ 0.33	$ 0.29		$ 0.33	$ 0.25	$ 0.22	$ 1.13		$ 1.03		$ 1.14
Diluted (in dollars per share)	$ 0.28		$ 0.26	$ 0.27	$ 0.33	$ 0.29		$ 0.33	$ 0.25	$ 0.22	$ 1.13		$ 1.02		$ 1.13
Research and development [Abstract]
Deferred revenue and customer advances	21,250,000					62,098,000					21,250,000		62,098,000
Research and development costs incurred											49,900,000	[4]	62,600,000	[4]	158,800,000	[4]
Less amounts funded by NASA											(5,800,000)		(21,900,000)		(108,000,000)
Net research and development expenses											44,100,000		40,700,000		50,800,000
Research and development costs incurred, inception to date	530,400,000										530,400,000											250,600,000
Less amounts funded by NASA, inception to date	(288,000,000)										(288,000,000)
Net research and development expenses, inception to date	242,400,000										242,400,000
Research and development expenses											89,233,000		114,205,000		102,751,000						530,000,000	15,800,000	42,600,000	34,300,000
Cash Received From Nasa																					288,000,000
Receivable From NASA																					0
Derivative [Line Items]
Total face value of forward exchange contracts																	21,400,000	16,400,000	72,900,000	56,000,000
Final expiration date of forward exchange contracts											Jan. 31, 2015
Fair value of forward exchange contracts	1,300,000										1,300,000
Basic weighted-average shares outstanding (in shares)											60,161		59,165		58,531
Basic weighted-average shares outstanding and unvested restricted stock units expected to vest (in shares)											60,247		59,428		59,078
Percentage allocated to shareholders (in hundredths)											99.80%	[3]	99.60%	[3]	99.10%	[3]
Number of Financial institutions holding money market funds	3										3
Cash equivalents	$ 260,000,000					$ 215,000,000					$ 260,000,000		$ 215,000,000

[1] In December 2013, the company recorded a $10.0 million pretax charge ($6.1 million after tax) to write off a non-current asset and a $3.7 million gain (pretax and after tax) on the sale of investments.

[2] In December 2012, the company recorded a $10.3 million pretax debt extinguishment charge ($6.3 million after tax) related to a financing transaction.

[3] Basic weighted-average shares outstanding 60,161 59,165 58,531 Basic weighted-average shares outstanding and unvested restricted share units expected to vest 60,247 59,428 59,078 Percentage allocated to shareholders 99.8% 99.6% 99.1%

[4] Includes associated general and administrative expenses.