Aggregate number of common shares reserved for future issuance.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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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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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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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 ($)		12 Months Ended
	Jun. 19, 2018	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2021	Jan. 01, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit recognized		$ 0	$ 0
weighted-average grant date fair value per share		$ 8.32	$ 3.73
Number of shares, granted			2,694,823
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		194,095	294,530
Unrecognized compensation cost		$ 1,996,300
Weighted-average remaining contractual term		2 years 3 months 18 days
Restricted Stock Units [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		79,600	160,500
Restricted Stock Units [Member] \| Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		11,780	45,330
Restricted Stock Units [Member] \| Certain Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		52,900
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 125,100
Weighted-average remaining contractual term		2 years 7 months 6 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Minimum [Member] \| Restricted Stock Units [Member] \| Certain Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		0
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		10 years
Maximum [Member] \| Restricted Stock Units [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years	3 years
Maximum [Member] \| Restricted Stock Units [Member] \| Certain Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, granted		105,800
2018 Stock Options and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage increase in number of shares of common stock reserved and available for issuance	4.00%
Number of shares available for future grant			96,868
Number of common shares reserved for issuance				183,726	22,980