Quarterly report pursuant to Section 13 or 15(d)

Summary of Potential Number of Shares Vesting under Restricted Stock Unit Awards (Detail)

v3.10.0.1
Summary of Potential Number of Shares Vesting under Restricted Stock Unit Awards (Detail)
$ in Thousands
9 Months Ended
Sep. 30, 2018
USD ($)
shares
Disclosure Of Restricted Stock Unit [Abstract]  
Number of shares vesting at IRR of at least 7% | shares 76,065
Number of shares vesting at IRR of at least 9.5% | shares 152,129
Number of shares vesting at IRR of at least 13% | shares 228,194
Value at grant at IRR of at least 7% | $ $ 2,967
Value at grant at IRR of at least 9.5% | $ 5,938
Value at grant at IRR of at least 13% | $ $ 8,906