Aggregate number of common shares reserved for future issuance.

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-Name Accounting Standards Codification
-Topic 210
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Amount of cost to be recognized for option under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Gross number of share options (or share units) granted during the period.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Stock Award Plans and Stock-based Compensation - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended
	Jan. 01, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit recognized		$ 0	$ 0	$ 0	$ 0
Number of stock options granted		4,750		5,200
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 142,900		$ 142,900
Weighted-average remaining contractual term				2 years 5 months 19 days
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		990		$ 990
Weighted-average remaining contractual term				1 month 13 days
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 1,352,000		$ 1,352,000
Weighted-average remaining contractual term				2 years 5 months 4 days
2018 Stock Option and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future grant		84,838		84,838
Number of common shares reserved for issuance	183,726
Percentage increase in number of shares of common stock reserved and available for issuance	4.00%