Annual report pursuant to Section 13 and 15(d)

Summary of Weighted-Average Grant-Date Fair Value of Options, Total Intrinsic Value of Options Exercised, and Cash Receipts from Options Exercised (Detail)

v3.8.0.1
Summary of Weighted-Average Grant-Date Fair Value of Options, Total Intrinsic Value of Options Exercised, and Cash Receipts from Options Exercised (Detail) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Aug. 31, 2017
Aug. 31, 2016
Aug. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]      
Weighted-average fair value of options granted (per share) $ 11.88 $ 8.63 $ 8.35
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value $ 2,208 $ 989 $ 366
Cash receipts from exercise of options $ 7,762 $ 3,564 $ 1,147