Stock-Based Compensation - Schedule of RSU and PRSU Award Activity (Details)	6 Months Ended
Jun. 30, 2020 $ / shares shares
Stock-based compensation expenses (restricted share units (“RSUs”) and performance-based RSUs (“PRSUs”)), before income taxes
RSUs and PRSUs, Nonvested, Number of Shares [Roll Forward]
Non-vested as of December 31, 2019 (shares) \| shares	2,024,768
Non-vested as of June 30, 2020 (shares) \| shares	2,127,354
RSUs and PRSUs, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Non-Vested, as of December 31, 2019 ($ per share) \| $ / shares	$ 22.09
Weighted Average Grant Date Fair Value, Non-Vested, as of June 30, 2020 ($ per share) \| $ / shares	$ 25.66
Restricted Stock Units (RSUs)
RSUs and PRSUs, Nonvested, Number of Shares [Roll Forward]
Granted (shares) \| shares	751,308
Vested (shares) \| shares	(653,685)
Forfeitures (shares) \| shares	(18,026)
RSUs and PRSUs, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Grants ($ per share) \| $ / shares	$ 29.91
Weighted Average Grant Date Fair Value, Vested ($ per share) \| $ / shares	22.88
Weighted Average Grant Date Fair Value, Forfeited ($ per share) \| $ / shares	$ 24.87
Performance Restricted Stock Units (PRSUs)
RSUs and PRSUs, Nonvested, Number of Shares [Roll Forward]
Granted (shares) \| shares	323,771
Vested (shares) \| shares	(298,824)
Forfeitures (shares) \| shares	(1,958)
RSUs and PRSUs, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Grants ($ per share) \| $ / shares	$ 29.60
Weighted Average Grant Date Fair Value, Vested ($ per share) \| $ / shares	22.53
Weighted Average Grant Date Fair Value, Forfeited ($ per share) \| $ / shares	$ 30.63

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

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)(iv)(3)
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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).

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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

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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

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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.

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