Stock-based Compensation - Summary of Changes in Non-vested Restricted Stock Awards (Details) - 2010 Plan - Restricted Stock Awards - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued, Non-vested beginning of period	436,000
Shares issued, Awards granted	3,000	148,000
Shares issued, Awards vested	(141,500)
Shares issued, Awards forfeited	(8,000)
Shares issued, Non-vested end of period	289,500
Weighted average grant date fair value, Non-vested beginning of period	$ 8.19
Weighted average grant date fair value, Awards granted	8.15
Weighted average grant date fair value, Awards vested	5.91
Weighted average grant date fair value, Awards forfeited	10.10
Weighted average grant date fair value, Non-vested end of period	$ 9.25
Aggregate intrinsic value, Non-vested end of year	$ 2,831

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.

+ References

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-Section 50
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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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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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-Publisher FASB
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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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No definition available.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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