Potential Vesting Percentage Range of Shares

No definition available.

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- Definition

Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 25
-Paragraph 19A
-URI http://asc.fasb.org/extlink&oid=107668666&loc=SL79513924-113897

+ Details

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ 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 (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

+ Details

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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.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of options vested.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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- Details

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- Details

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Period Type:

Equity-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions			9 Months Ended		12 Months Ended
	Aug. 01, 2018	Jun. 26, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options vested (in shares)	456,613
Weighted-average grant-date fair value (in usd per share)	$ 35.93
Payment of incentive compensation plan withholding taxes			$ 27.1	$ 42.0
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payment of incentive compensation plan withholding taxes			$ 19.0
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards vested in the period (in shares)					321,880	748,855
Potential vesting percentage range of shares					192.00%	193.50%
Awards vested, weighted average grant date fair value (in usd per share)					$ 37.84	$ 24.40
Payment of incentive compensation plan withholding taxes					$ 9.0	$ 18.0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of awards vested in the period (in shares)		997,450
Awards vested, weighted average grant date fair value (in usd per share)		$ 17.04
Payment of incentive compensation plan withholding taxes				$ 24.0