Summary of Potential Number of Shares Vesting under Restricted Stock Unit Awards (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($) shares
Schedule of Restricted Stock Unit [Line Items]
Number of shares vesting at IRR of at least 6.0% | shares	84,554
Number of shares vesting at IRR of at least 8.0% | shares	169,107
Number of shares vesting at IRR of at least 10.0% | shares	253,661
Value at grant at IRR of at least 6.0% | $	$ 2,522
Value at grant at IRR of at least 8.0% | $	5,044
Value at grant at IRR of at least 10.0% | $	$ 7,568