Stock Based Compensation (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	$ 955	$ 637
Expected vesting percent	50.00%
2015 LTIP (performance-based)
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	$ 488	529
2017 LTIP (time-based)
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	344	0
ESPP
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	15	0
Board Of Directors | Board of Directors restricted stock | Restricted Stock
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	$ 108	$ 108