Equity-Based Compensation - Summary of Restricted Stock Activity Under the 2010 Plan, Equity Plan and the 1991 Restricted Stock Plan (Details) - Restricted Stock [Member] - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
2020 Equity Award Plan [Member]
Restricted Stock Activity
Restricted stock and stock units, granted	267,036
Released (in shares)	(11,912)
Canceled or forfeited (in shares)	(4,558)
End of period, outstanding (in shares)	250,566
Restricted stock grants (in shares)	267,036
Weighted-Average Fair Value
Restricted stock grants (weighted-average fair value)	$ 9.55
Released (weighted-average fair value)	9.44
Canceled or forfeited (weighted-average fair value)	10.11
End of period (weighted-average fair value)	$ 9.54
2010 Equity Award Plan [Member]
Restricted Stock Activity
Beginning of period, outstanding (in shares)	1,484,985	1,146,884	850,927
Restricted stock and stock units, granted		599,928	636,268
Released (in shares)	(408,232)	(131,949)	(112,160)
Canceled or forfeited (in shares)	(147,008)	(129,878)	(228,151)
End of period, outstanding (in shares)	929,745	1,484,985	1,146,884
Restricted stock grants (in shares)		599,928	636,268
Weighted-Average Fair Value
Beginning of period (weighted-average fair value)	$ 5.35	$ 5.49	$ 6.65
Restricted stock grants (weighted-average fair value)		5.02	4.42
Released (weighted-average fair value)	5.13	5.02	5.59
Canceled or forfeited (weighted-average fair value)	7.68	5.41	6.80
End of period (weighted-average fair value)	$ 5.07	$ 5.35	$ 5.49
2000 Equity Award Plan [Member]
Restricted Stock Activity
Beginning of period, outstanding (in shares)	40,000	40,000	40,000
Released (in shares)	(40,000)
End of period, outstanding (in shares)		40,000	40,000
Weighted-Average Fair Value
Beginning of period (weighted-average fair value)	$ 4.97	$ 4.97	$ 4.97
Released (weighted-average fair value)	$ 4.97
End of period (weighted-average fair value)		$ 4.97	$ 4.97
1991 Equity Award Plan [Member]
Restricted Stock Activity
Beginning of period, outstanding (in shares)	10,980	24,375	56,117
Released (in shares)	(10,730)	(11,470)	(20,868)
Canceled or forfeited (in shares)	(250)	(1,925)	(10,874)
End of period, outstanding (in shares)		10,980	24,375
Weighted-Average Fair Value
Beginning of period (weighted-average fair value)	$ 5.75	$ 5.75	$ 5.87
Released (weighted-average fair value)	5.75	5.75	6.40
Canceled or forfeited (weighted-average fair value)	$ 5.75	5.75	5.15
End of period (weighted-average fair value)		$ 5.75	$ 5.75

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

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-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).

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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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