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		6 Months Ended
	Jun. 20, 2016	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
PRSU
Shares of common stock authorized to issue under equity award plan	10,000,000
Stock-based compensation expense		$ 3,135	$ 3,529	$ 6,207	$ 6,838
Below 25th Percentile [Member]
PRSU
Shares granted and outstanding, Vesting percentage				0.00%
Above 25th Percentile [Member]
PRSU
Shares granted and outstanding, Vesting percentage				50.00%
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%