Loan Transactions and Related Notes Receivable - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			3 Months Ended
	Oct. 31, 2013 First Credit Agreement	Jan. 31, 2009 First Credit Agreement	Jan. 31, 2009 Second Credit Agreement	Oct. 31, 2013 Third Credit Agreement	Dec. 31, 2009 Third Credit Agreement
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan amount		$ 10,000	$ 10,000		$ 10,000
Original principal amount outstanding	$ 1,300			$ 8,500
Notes receivable, maturity	Jan. 15, 2014			Aug. 30, 2015