Equity Investment (Detail) - TH2 - USD ($) $ in Thousands	3 Months Ended
Oct. 31, 2019	Oct. 31, 2018	Jul. 31, 2019
Schedule of Equity Method Investments [Line Items]
Losses from investment	$ 2,095	$ 1,483
Loan to joint venture	1,534
Loan to joint venture, outstanding balance	$ 3,691		$ 2,157

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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