Derivatives and Hedging (Details) - Interest Rate Swap $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2016 USD ($) Derivative	Jan. 31, 2015 USD ($)	Jan. 31, 2016 USD ($) Derivative	Jan. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)
Derivative [Line Items]
Number of interest rate derivatives held | Derivative	2		2
Reclassification adjustment out of other comprehensive income into interest expense	$ 200	$ 400	$ 500	$ 900
Description of interest rate cash flow hedge accounting method			Hypothetical derivative method
Description of types of interest rate cash flow hedging instruments used			Interest rate swap
Other liabilities
Derivative [Line Items]
Interest rate swap derivative	$ 0		$ 0		$ 446