Fair Value Measurements using Significant Unobservable Inputs (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
Schedule of Pension and Other Postretirment Plan Assets by Fair Value [Line Items]
Balance at beginning of fiscal year	$ 10,536	$ 7,965
Actual return on plan assets
Relating to assets still held at end of fiscal year	112	812
Relating to assets sold during the period
Purchases, sales, and settlements	700	1,146
Transfers in and/or out of Level 3
Foreign currency exchange gain/(loss)	(493)	613
Balance at end of fiscal year	$ 10,855	$ 10,536