Stock-Based Compensation - Additional Information (Detail)	1 Months Ended				3 Months Ended		12 Months Ended	15 Months Ended	27 Months Ended	39 Months Ended
	Jan. 31, 2022 Milestone shares	Jan. 31, 2021 Milestone shares	Jan. 31, 2020 Milestone shares	Jan. 31, 2019 Milestone shares	Mar. 31, 2022 USD ($) Period $ / shares shares	Mar. 31, 2021 USD ($)	Dec. 31, 2019	Mar. 31, 2022 USD ($) shares	Mar. 31, 2022 USD ($) shares	Mar. 31, 2022 USD ($) shares	Jan. 01, 2022 shares	Dec. 31, 2021 shares	Apr. 28, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 2,357,000	$ 1,577,000
Forfeited awards					15,000
Cash proceeds from exercises of stock options | $					$ 0	$ 156,000
Weighted average fair value of stock options granted to employees | $ / shares					$ 3.53
Excess tax benefit from stock-based awards | $					$ 0
Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Milestone achievement period	4 years	4 years	4 years	4 years			4 years
Issuance of performance based award	657,000	205,500	244,000	221,600
Percentage of shares vested upon achievement of certain milestone			100.00%	100.00%
Number of milestones to be achieve | Milestone			3	3
Forfeited awards					40,000
Performance Based Restricted Stock Units [Member] | PRSU Awards Vesting Upon the Achievement of Three of the Milestones Over a Four Year Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares vested upon achievement of certain milestone	100.00%	100.00%
Number of milestones to be achieve | Milestone	3	3
Performance Based Restricted Stock Units [Member] | PRSU Awards Vesting Upon the Achievement of Four of the Milestones Over a Four Year Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares vested upon achievement of certain milestone		133.30%
Number of milestones to be achieve | Milestone		4
Performance Based Restricted Stock Units [Member] | PRSU Awards Vesting Upon the Achievement of All Four of the Milestones Over a Four Year Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares vested upon achievement of certain milestone	133.30%
Number of milestones to be achieve | Milestone	4
Performance Based Restricted Stock Units [Member] | January 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 60,000					$ 1,300,000
Performance Based Restricted Stock Units [Member] | January 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 60,000				$ 1.8
Forfeiture of performance based award					10,500
Performance Based Restricted Stock Units [Member] | January 2021 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 133,000			$ 668,000
Forfeiture of performance based award					7,500
Performance Based Restricted Stock Units [Member] | January 2022 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation | $					$ 520,000
Forfeiture of performance based award					0
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance, description					Initially, a total of 1,527,770 shares of the Company’s common stock were reserved for issuance pursuant to the 2014 Plan. The number of shares available for issuance under the 2014 Plan will, unless otherwise determined by the Company’s Board of Directors or the Compensation Committee, be automatically increased on January 1 of each year commencing on January 1, 2016 and ending on (and including) January 1, 2024, in an amount equal to 3.5% of the total number of shares of the Company’s common stock outstanding on December 31 of the preceding calendar year.
Percentage of common stock outstanding to increase shares reserved for issuance					3.50%
Common stock reserved for future issuance												5,383,372	1,527,770
Additional number of shares of common stock reserved for issuance											2,738,694
Number of common shares available for grant					6,203,285			6,203,285	6,203,285	6,203,285
2014 ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance, description					The number of shares available for issuance under the ESPP will, unless otherwise determined by the Company’s Board of Directors or the Compensation Committee, be automatically increased on January 1 of each year commencing on January 1, 2016 and ending on (and including) January 1, 2024, in an amount equal to 1% of the total number of shares of the Company’s common stock outstanding on December 31 of the preceding calendar year.
Percentage of common stock outstanding to increase shares reserved for issuance					1.00%
Common stock reserved for future issuance												2,978,312	458,331
Additional number of shares of common stock reserved for issuance											782,484
Number of common shares available for grant					3,760,796			3,760,796	3,760,796	3,760,796
Duration of employee stock purchase plan as determined by the compensation committee					24 months
Duration for offering period, employee stock purchase plan					6 months
Employee stock purchase plan, number of purchase periods | Period					4
Maximum duration for purchase under employee stock purchase plan					1 year
Maximum duration of employee stock purchase plan					27 months
Percentage of purchase of common stock					85.00%
Percentage of common stock on the date of purchase					85.00%