Deferred Revenue (Details2) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Deferred revenue
Balance at the beginning of the period	$ 426.1us-gaap_DeferredRevenue
Cash collections	115.1us-gaap_DeferredRevenueAdditions
Revenue recognized from deferred revenue	(134.9)
Balance at the end of the period	406.3us-gaap_DeferredRevenue
U.S. Government \| Enhanced View SLA
Deferred revenue
Balance at the beginning of the period	210.0
Cash collections	75.0
Revenue recognized from deferred revenue	(84.3)
Balance at the end of the period	200.7
U.S. Government \| Value Added Services
Deferred revenue
Balance at the beginning of the period	77.7
Cash collections	11.3
Revenue recognized from deferred revenue	(15.5)
Balance at the end of the period	73.5
U.S. Government \| Pre-FOC Payments Related To NextView
Deferred revenue
Balance at the beginning of the period	88.8
Revenue recognized from deferred revenue	(3.8)
Balance at the end of the period	85.0
Diversified commercial \| DAP
Deferred revenue
Balance at the beginning of the period	39.4
Cash collections	14.4
Revenue recognized from deferred revenue	(15.4)
Balance at the end of the period	38.4
Diversified commercial \| Other
Deferred revenue
Balance at the beginning of the period	10.2
Cash collections	14.4
Revenue recognized from deferred revenue	(15.9)
Balance at the end of the period	$ 8.7

Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response)

-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

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Period Type:	instant

- Definition

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

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- Definition

Amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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- Details

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Balance Type:	na
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- Details

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- Details

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