Revenue and Contracts with Customers (Contract with Customer Asset and Liability) (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Jun. 30, 2020	Dec. 31, 2019
Deferred costs associated with deferred revenue		$ 145.4	$ 144.1
Provision for Loss on Contracts		13.0
Loss on contracts	$ 0.0
Deferred revenue		248.2	243.0
Advances from customers, current		0.0	23.3
Advances from customer, noncurrent		44.4	29.4
Government [Member]
Provision for Loss on Contracts		9.1	10.0
Provision for loss on contracts, noncurrent		$ 3.9	$ 8.3

Advances from customers, current

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- Definition

Provision for loss on contracts, noncurrent

+ References

No definition available.

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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 noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(5))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 35
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57763-111642

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- Definition

Net amount of other deferred costs capitalized at the end of the reporting period. Does not include deferred finance costs or deferred acquisition costs of insurance companies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Cumulative provision for contract losses not offset against related costs accumulated on the balance sheet.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 35
-Section 45
-Paragraph 2
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