Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Disclosure of information about share-based payment arrangement.

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Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jun. 13, 2018	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Stock options granted		450,900	612,050
Number of common stock available for future grant		1,014,126
Number of shares of common stock issued to certain board members in lieu of cash compensation		24,235	6,790
Shares remaining outstanding		1,577,541
Stock-based compensation expense		$ 3,204	$ 2,606
Employee Stock Option
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Expected term of stock options		5 years 11 months 23 days	6 years 14 days
Unrecognized employee stock based compensation expense		$ 5,300
Unrecognized employee stock based compensation expense, period for recognition		2 years 4 months 28 days
2018 Employee Stock Purchase Plan
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Number of common stock available for future grant		218,692
Number of common stock authorized for issuance		239,545
Number of common stock stock issued		20,853
Stock-based compensation expense		$ 100	$ 30
2018 Omnibus Incentive Plan
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Number of common stock available for future grant	1,500,000
2018 Employee Stock Purchase Plan
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Maximum employee subscription rate	15.00%
2018 Employee Stock Purchase Plan \| Maximum
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Percentage of fair market value of common stock	85.00%