Stock-Based Compensation and Employee Stock Purchase Program - Additional Information (Detail)				1 Months Ended	3 Months Ended
	Feb. 02, 2022 shares	May 20, 2015 shares	May 14, 2015	Jun. 30, 2019 shares	Mar. 31, 2024 USD ($) IncentivePlan shares	Mar. 31, 2023 USD ($)	Dec. 31, 2023 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans | IncentivePlan					2
Shares Subject to Outstanding, Options granted					0
Total number of options outstanding					76,682		80,030
Intrinsic value of options exercised | $					$ 0
Unrecognized compensation cost related to unvested stock-based compensation grants | $					$ 495,000
Weighted-average remaining recognition period					9 months 18 days
Stock-based compensation | $					$ 138,000	$ 212,000
2015 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of shares reserved for issuance under plan					5,309
Stock-based compensation | $					$ 2,000	$ 1,000
Percentage in payroll deductions to acquire shares of common stock			15.00%
Purchase plan offering period			6 months
Employees are able to purchase company's common stock on first trading day of offering period, percentage			85.00%
Issuance of common stock pursuant to employee stock purchase plan					5,971
First offering period, start date			May 14, 2015
First offering period, end date			Feb. 01, 2016
Inducement Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of options outstanding					8,145		8,366
Inducement Stock Option [Member] | Stanley Jacot, Jr. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Subject to Outstanding, Options granted	7,902
2015 Omnibus Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Terms under the plan					The 2015 Plan became effective upon the Company’s IPO in May 2015 and all shares that were reserved, but not issued, under the 2006 Plan were assumed by the 2015 Plan. Upon effectiveness, the 2015 Plan had 3,860 shares of common stock reserved for future issuance, which included 259 that were transferred to and assumed by the 2015 Plan. The 2015 Plan provides for automatic annual increases in shares available for grant. In addition, shares subject to awards under the 2006 Plan that are forfeited or canceled will be added to the 2015 Plan.
Total number of shares reserved for issuance under plan		3,860			138,248
Options vesting period		4 years
Additional shares authorized for issuance under the plan				3,000
Common stock available for future grant					69,766
Total number of options outstanding					68,482		71,609
2015 Omnibus Equity Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable period		10 years
2006 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of shares reserved for issuance under plan		259
Total number of options outstanding					102		102