The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Stock-Based Awards - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Jun. 20, 2016	Mar. 31, 2019	Mar. 31, 2018
PRSU
Shares of common stock authorized to issue under equity award plan	10,000,000
Stock-based compensation expense		$ 3,072	$ 3,309
Below 25th Percentile [Member]
PRSU
Shares granted and outstanding, Vesting percentage		0.00%
At 50th Percentile [Member]
PRSU
Shares granted and outstanding, Vesting percentage		100.00%
At 100th Percentile [Member]
PRSU
Shares granted and outstanding, Vesting percentage		200.00%
Performance Based Restricted Stock Unit [Member] \| Maximum [Member]
PRSU
Shares granted and outstanding, Vesting percentage		200.00%
Performance Based Restricted Stock Unit [Member] \| Minimum [Member]
PRSU
Shares granted and outstanding, Vesting percentage		0.00%