Notes Payable - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2014	Oct. 31, 2013	Jul. 31, 2014
Notes Payable [Line Items]
Notes payable	$ 94,708		$ 61,422
Letters of Credit Outstanding	3,500
Proceeds from borrowing on notes payable	41,000	0
USD-denominated credit facility China [Member]
Notes Payable [Line Items]
Repayments of Lines of Credit	7,714
Maximum Amount Outstanding	19,422
Remaining borrowing capacity	12,492
Maximum Borrowing Capacity	24,200
USD-Denominated Borrowing Credit Revolver [Member]
Notes Payable [Line Items]
Notes payable	83,000		42,000
Remaining borrowing capacity	213,500
Maximum Borrowing Capacity	$ 363,500