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)

v3.19.3
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, 2019
Aug. 31, 2018
Aug. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]      
Weighted-average fair value of options granted (per share)     $ 11.88
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value $ 429 $ 5,284 $ 2,208
Proceeds from Stock Options Exercised $ 1,404 $ 15,140 $ 7,762
Expected forfeiture rate 10.00% 10.00% 11.00%