Accounts Receivable and Notes Receivable and Credit Quality of Receivables - Components of Accounts and Notes Receivable (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current:
Accounts receivable	$ 615.1	$ 551.5
Notes receivable	138.4	164.1
Allowance for doubtful accounts	(40.4)	(31.2)
Current accounts and notes receivable, net	713.1	684.4
Long-term:
Accounts and notes receivable, net of allowance of $0.1 and $0.2	40.2	52.8
Total accounts and notes receivable, net	753.3	737.2
Accounts and notes receivable allowance	$ 0.1	$ 0.2

Allowance For Accounts, Notes, And Loans Receivable, Noncurrent

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- Definition

The aggregate of amounts due from customers or clients, within one year of the balance sheet date (or one operating cycle, if longer), for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date within one year of the balance sheet, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

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- References

No definition available.

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Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

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- Definition

A valuation allowance relating to a written agreement to receive money (at a specified future date(s) within one year from the reporting date (or the normal operating cycle, whichever is longer), consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

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- Definition

The aggregate of amounts due from customers or clients more than one year from the balance sheet date, for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money at a future date more than one year from the balance sheet date, reduced to their estimated net realizable fair value by an allowance established by the Company of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

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- Definition

An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date(s) within one year of the balance sheet date or the normal operating cycle, whichever is longer. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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