Long-term Compensation Plans - Schedule Equity Classified Share Based Payment RSUs (Details) - shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining vesting period (months)	13 months
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	3,034,193	2,623,851
Weighted average remaining vesting period (months)	13 months
Potential additional awards (in shares)	2,472,416
Service-based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	1,002,085
Weighted average remaining vesting period (months)	6 months
Potential additional awards (in shares)	0
Performance-based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	1,482,846
Weighted average remaining vesting period (months)	18 months
Potential additional awards (in shares)	1,351,323
Market-based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	549,262
Weighted average remaining vesting period (months)	10 months
Potential additional awards (in shares)	1,121,093

Share-based Compensation Arrangement by Share-based Payment Award, Number Of Additional Awards Available

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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

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.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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)(1)(ii)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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