Goodwill And Other Intangible Assets (Reconciliation Of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Apr. 30, 2012
Goodwill [Line Items]
Balance as of July 31, 2011	$ 171,741
Foreign exchange translation	(5,138)
Balance as of April 30, 2012	166,603
Engine Products [Member]
Goodwill [Line Items]
Balance as of July 31, 2011	72,966
Foreign exchange translation	(688)
Balance as of April 30, 2012	72,278
Industrial Products [Member]
Goodwill [Line Items]
Balance as of July 31, 2011	98,775
Foreign exchange translation	(4,450)
Balance as of April 30, 2012	$ 94,325