Share-Based Compensation - Summary of Company's Restricted Stock Activity (Detail)	9 Months Ended
Sep. 30, 2020 $ / shares shares
Restricted Stock
Number of Shares
Balance at beginning of period (in shares) \| shares	13,110
Granted (in shares) \| shares	13,041
Vested (in shares) \| shares	(13,052)
Balance at end of period (in shares) \| shares	13,099
Weighted Average Price
Balance at beginning of period (in usd per share) \| $ / shares	$ 15.93
Granted (in usd per share) \| $ / shares	16.87
Vested (in usd per share) \| $ / shares	15.96
Balance of end of period (in usd per share) \| $ / shares	$ 16.83
RSUs
Number of Shares
Balance at beginning of period (in shares) \| shares	300,629
Granted (in shares) \| shares	175,869
Vested (in shares) \| shares	(92,432)
Forfeited (in shares) \| shares	(8,736)
Balance at end of period (in shares) \| shares	375,330
Weighted Average Price
Balance at beginning of period (in usd per share) \| $ / shares	$ 18.13
Granted (in usd per share) \| $ / shares	15.37
Vested (in usd per share) \| $ / shares	18.80
Forfeited (in usd per share) \| $ / shares	18.03
Balance of end of period (in usd per share) \| $ / shares	$ 16.67

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)
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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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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).

+ References

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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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-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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-Publisher FASB
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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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