Notes Payable Notes Payable - Schedule of Borrowings (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Jul. 31, 2012
Short-term Debt [Line Items]
Weighted average borrowing rate	1.3226%
Outstanding balance on credit facility	$ 112,340	$ 0
USD-Denominated Borrowing [Member]
Short-term Debt [Line Items]
Interest rate	1.30%
Balance	13,000
EUR-Denominated Borrowing [Member]
Short-term Debt [Line Items]
Interest rate	1.18%
Balance	66,478
GBP-Denominated Borrowing [Member]
Short-term Debt [Line Items]
Interest rate	1.62%
Balance	$ 32,862