Revenue Recognition - Schedule of Contract Asset and Liability (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Contract assets	$ 308.9	$ 310.9
Reserve for overhead rate disallowance	(42.9)	(42.8)
Contract assets, net of reserve	266.0	268.1
Contract liabilities	212.6	276.8
Net contract assets (liabilities), net of reserve	$ 53.4	$ (8.7)

Contract with Customer, Asset (Liability), Net

No definition available.

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- Definition

Amount of accumulated credit loss for right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
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-Publisher FASB
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- Definition

Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- References

No definition available.

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