Stock-Based Awards - Summary of Restricted Stock Activity (Detail) - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited, Shares		(5,641)
Weighted- Average Grant Date Fair Value, Forfeited		$ 5.39
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested Beginning Balance, Shares	3,580,743	3,244,558	1,957,102
Granted, Shares	1,642,266	1,653,186	2,794,703
Vested, Shares	(1,897,699)	(1,206,879)	(1,053,980)
Forfeited, Shares	(288,405)	(110,122)	(453,267)
Unvested Ending Balance, Shares	3,036,905	3,580,743	3,244,558
Weighted-Average Grant Date Fair Value, Unvested, Beginning Balance	$ 5.38	$ 7.29	$ 11.47
Weighted- Average Grant Date Fair Value, Granted	5.46	3.80	6.16
Weighted- Average Grant Date Fair Value, Vested	5.78	8.13	11.25
Weighted- Average Grant Date Fair Value, Forfeited	5.11	4.79	9.09
Unvested Weighted-Average Grant Date Fair Value, Ending Balance	$ 5.20	$ 5.38	$ 7.29
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested Beginning Balance, Shares	39,408	39,278	9,494
Granted, Shares	31,170	32,901	35,283
Vested, Shares	(15,136)	(27,130)	(5,499)
Forfeited, Shares	(452)
Unvested Ending Balance, Shares	54,990	39,408	39,278
Weighted-Average Grant Date Fair Value, Unvested, Beginning Balance	$ 4.46	$ 7.20	$ 11.52
Weighted- Average Grant Date Fair Value, Granted	5.43	3.82	6.45
Weighted- Average Grant Date Fair Value, Vested	4.73	7.45	9.85
Weighted- Average Grant Date Fair Value, Forfeited	5.37
Unvested Weighted-Average Grant Date Fair Value, Ending Balance	$ 4.93	$ 4.46	$ 7.20
Performance Based Restricted Stock Unites (PRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested Beginning Balance, Shares	341,312		232,610
Granted, Shares	257,043	117,013	270,872
Forfeited, Shares	(47,669)	(8,311)	(38,262)
Unvested Ending Balance, Shares	550,686	341,312
Weighted-Average Grant Date Fair Value, Unvested, Beginning Balance	$ 5.17		$ 6.24
Weighted- Average Grant Date Fair Value, Granted	6.49	$ 3.11	6.24
Weighted- Average Grant Date Fair Value, Forfeited	5.74	6.24	$ 6.24
Unvested Weighted-Average Grant Date Fair Value, Ending Balance	$ 5.73	$ 5.17

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

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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.

+ References

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-Publisher FASB
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-Topic 718
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-Paragraph 2
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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).

+ References

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-Publisher FASB
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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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-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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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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- 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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