Revenue Recognition - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue from Contract with Customer [Abstract]
Increase (decrease) in revenue recognized from changes in transaction prices	$ 0.1	$ (0.4)	$ 0.3	$ (0.4)
Revenue recognized, services performed prior to reaching enforceable agreement	$ 2.7	$ 0.0	3.9	0.0
Revenue recognized that was included in the contract liability balance at the beginning of the period			68.2	50.3
Revenue recognized, advance billings			$ 66.7	$ 47.8

Contract with Customer, Liability, Revenue Recognized, Advance Billings

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

Sales Revenue, Services Performed Prior To Agreement, Net

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in estimate of transaction price which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due. Includes, but is not limited to, change in assessment of whether estimate of variable consideration is constrained.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130551-203045

+ Details

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

+ Details

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- References

No definition available.

+ Details

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