Stock-Based Compensation - Additional Information (Detail) - Director - USD ($)	1 Months Ended
	May 31, 2019	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non option equity instruments granted per director (in shares)	193
Non option equity instruments grant date fair value per grant	$ 56,250
Non option equity instruments grant date fair value total	$ 394,000
Non option equity instruments, outstanding, number (in shares)		11,408
Shares available for future grant under the plan (in shares)		494,379