Share-Based Payments - Total Shareholder Return Units Narrative (Details) - Total Shareholder Return Units (TSRUs) [Member]		12 Months Ended
Oct. 26, 2016 USD ($) Employee trading_day	Dec. 31, 2018 Employee trading_day
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Trading day average used to calculate the conversion \| trading_day	20	20
Age of eligible unit holder which can elect to exercise and convert TSRUs when vested into PTUs	55 years
Award requisite service period	10 years
Number of employees affected by plan modification \| Employee	2,900	260
Incremental compensation cost resulting from plan modification \| $	$ 0
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term (years)		5 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term (years)		7 years

Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Age Requirement

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Value Conversion, Trading Day Average

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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

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- Definition

The number of employees affected by the modification of an equity-based compensation plan.

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

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- Definition

Period from grant date that an equity-based award expires, 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)(2)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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