Revenue from Contracts with Customers - Costs of Obtaining Contracts (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Prepaid expenses and other
Costs of Obtaining Contracts with Customers
Current portion of costs of obtaining contracts with customers	$ 8.8	$ 6.0
Other noncurrent assets
Costs of Obtaining Contracts with Customers
Non-current portion of costs of obtaining contracts with customers	$ 28.4	$ 20.3

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- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as noncurrent.

+ References

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