The aggregate fair value as of the grant date of equity-based award plans other than stock (unit) option plans.

No definition available.

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Expected Per Share Amount

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Target Value, Per Share Amount

+ References

No definition available.

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- Definition

The percentage of the performance unit value determined on annual performance.

+ References

No definition available.

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- Definition

The percentage of the performance unit value determined on total vesting period performance.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Period For Value Determination

+ References

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable after one year (or the operating cycle, if longer).

+ References

No definition available.

+ Details

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions		9 Months Ended
	Feb. 27, 2018	Sep. 30, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period for remaining recognition of compensation expense		1 year 9 months
Unrecognized compensation cost related to nonvested share-based compensation arrangements		$ 36.4
Performance Shares [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	36 months
February 27, 2018 Grant [Member] \| Restricted Share Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based awards, grant-date fair value	$ 16.6
Weighted-average period for remaining recognition of compensation expense	2 years 8 months 12 days
Awards vesting period	3 years
February 27, 2018 Grant [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based awards, grant-date fair value	$ 6.4
Awards vesting period	3 years
Target value of P-Units (in dollars per unit)	$ 100
February 27, 2018 Grant [Member] \| Performance Shares [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected payout on P-Units (in dollars per unit)	$ 0
February 27, 2018 Grant [Member] \| Performance Shares [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	3 years
Expected payout on P-Units (in dollars per unit)	$ 200
February 27, 2018 Grant [Member] \| Performance Shares [Member] \| One-Year Period Ending December 31, 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance unit value percentage determined on an annual performance	25.00%
Period for value determination	1 year
February 27, 2018 Grant [Member] \| Performance Shares [Member] \| One-Year Period Ending December 31, 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance unit value percentage determined on an annual performance		25.00%
Period for value determination		1 year
February 27, 2018 Grant [Member] \| Performance Shares [Member] \| One-Year Period Ending December 31, 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance unit value percentage determined on an annual performance		25.00%
Period for value determination		1 year
February 27, 2018 Grant [Member] \| Performance Shares [Member] \| Three-Year Period Ending December 31, 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for value determination	3 years
Performance unit value percentage determined on total vesting period performance	25.00%
Other Current Liabilities [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated liabilities for share-based compensation awards classified as short-term		$ 8.5	$ 11.5
Other Noncurrent Liabilities [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated liabilities for share-based compensation awards classified as long-term		$ 5.8	$ 10.5