Amount of noncash expense for share-based payment arrangement.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Stock option issuance period.

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Stock-Based Awards - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Jun. 20, 2016	Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Award
Stock option issuance period		10 years
Option vested period		1 year
Shares of common stock authorized to issue under equity award plan	10,000,000
Stock-based compensation expense		$ 3,239	$ 3,072
Below 25th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		0.00%
At 25th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		50.00%
At 50th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		100.00%
At 100th Percentile [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		200.00%
Performance Based Restricted Stock Unit [Member] \| Maximum [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		200.00%
Performance Based Restricted Stock Unit [Member] \| Minimum [Member]
Share-based Payment Award
Shares granted and outstanding, Vesting percentage		0.00%