Share-based Compensation - Omnibus Incentive Plan (Details) - The 2018 Omnibus Incentive Plan [Member] - $ / shares	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance, in shares		3,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, beginning balance (in shares)	270,742
Granted, number of shares (in shares)	730,211
Vested, number of shares (in shares)	(83,157)
Forfeited, number of shares (in shares)	(99,523)
Unvested, ending balance (in shares)	818,273
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Unvested, weighted average, beginning (in dollars per share)	$ 14.20
Granted, weighted average grant date fair value (in dollars per share)	8.21
Vested, weighted average grant date fair value (in dollars per share)	14.16
Forfeited, weighted average grant date fair value (in dollars per share)	8.43
Unvested, weighted average, ending (in dollars per share)	$ 9.55

Aggregate number of common shares reserved for future issuance.

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-Name Accounting Standards Codification
-Topic 210
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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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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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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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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