Share-Based Compensation - Restricted Stock Award Activity (Details) - Restricted Stock Units (RSUs)	12 Months Ended
Dec. 31, 2021 $ / shares shares
Restricted Stock Units
Nonvested at December 31, 2020 \| shares	1,629,956
Granted \| shares	752,039
Vested \| shares	(826,473)
Forfeited \| shares	(451,694)
Nonvested at December 31, 2021 \| shares	1,103,828
Weighted Average Grant-Date Fair Value
Nonvested at December 31, 2020 \| $ / shares	$ 14.49
Granted \| $ / shares	4.14
Vested \| $ / shares	13.81
Forfeited \| $ / shares	9.90
Nonvested at December 31, 2021 \| $ / shares	$ 8.99

Restricted Stock Units [Abstract]

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Weighted Average Grant-Date Fair Value [Abstract]

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

+ 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)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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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-Publisher FASB
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-Topic 718
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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).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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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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-Publisher FASB
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- Definition

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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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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