Amount 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, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The current portion of prepayments received from customers for goods or services to be provided in the future.

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- Definition

Amount awarded from other party in judgment or settlement of litigation.

+ References

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- Definition

Cash receipts from customers during the current period which are usually for sales of goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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Subsequent Event (Details) - USD ($) $ in Millions	3 Months Ended
Subsequent Event (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Accounts receivable, net		$ 60.2	$ 19.9
Customer Advances, Current		19.3
Government [Member]
Subsequent Event [Line Items]
Accounts receivable, net		14.5
Customer Advances, Current		$ 19.3
Scenario, Forecast [Member] \| Government [Member]
Subsequent Event [Line Items]
Litigation Settlement, Amount Awarded from Other Party	$ 24.0
Proceeds on claims	$ 4.7