Stock-Based Compensation - Additional Information (Details)	6 Months Ended
Jun. 30, 2019 $ / shares shares
PSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share units granted \| shares	212,000
Weighted-average grant date fair value \| $ / shares	$ 23.99
PSUs \| Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share units performance period	3 years
Award vesting period	3 years
PSUs \| Minimum \| Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share units vesting percentage	0.00%
PSUs \| Maximum \| Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share units vesting percentage	200.00%
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of share units granted \| shares	558,000
Weighted-average grant date fair value \| $ / shares	$ 23.84
RSUs \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	1 year
RSUs \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	4 years

Share based compensation arrangement by share based payment award performance period.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ 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)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target 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 (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&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.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

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