Accounts Receivable and Notes Receivable and Credit Quality of Receivables - Allowance for Notes Receivable (Details) - Notes Receivable - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning allowance for notes receivable	$ (20.8)
Provision	(6.3)	$ (7.3)
Charge-offs and recoveries	2.7	1.5
Ending allowance for notes receivable	$ (24.4)	$ (20.8)

Financing Receivable, Allowance for Credit Losses, Recoveries And Write-Downs, Net

No definition available.

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Balance Type:	credit
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Balance Type:	debit
Period Type:	duration

- Details

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