Segment Reporting (Net Sales By Product Within Engine Products Segment And Industrial Products Segment) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Segment Reporting Information [Line Items]
Net sales		$ 610,578	$ 575,588	$ 588,537	$ 596,510	$ 668,226	$ 624,234	$ 581,622	$ 599,384	$ 2,371,213	$ 2,473,466	$ 2,436,948
Engine Products [Member]
Segment Reporting Information [Line Items]
Net sales										1,484,132	1,584,027	1,504,188
Industrial Products [Member]
Segment Reporting Information [Line Items]
Net sales										887,081	889,439	932,760
Europe [Member]
Segment Reporting Information [Line Items]
Net sales										671,296	728,554	678,996
Other Credit Derivatives [Member]
Segment Reporting Information [Line Items]
Net sales										222,003	207,681	200,612
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Net sales										470,661	517,305	546,406
Aerospace And Defense Products [Member] | Engine Products [Member]
Segment Reporting Information [Line Items]
Net sales										103,851	99,628	104,191
Aftermarket Products [Member] | Engine Products [Member]
Segment Reporting Information [Line Items]
Net sales	[1]									980,756	1,012,165	912,717
Off Road Products [Member] | Engine Products [Member]
Segment Reporting Information [Line Items]
Net sales										261,120	342,205	358,834
On Road Products [Member] | Engine Products [Member]
Segment Reporting Information [Line Items]
Net sales										138,405	130,029	128,446
Gas Turbine Products [Member] | Industrial Products [Member]
Segment Reporting Information [Line Items]
Net sales										186,919	156,860	232,922
Industrial Filtration Solutions Products [Member] | Industrial Products [Member]
Segment Reporting Information [Line Items]
Net sales										528,917	553,356	529,751
Domestic Country [Member]
Segment Reporting Information [Line Items]
Net sales										1,007,253	1,019,926	1,010,934
Special Applications Products [Member] | Industrial Products [Member]
Segment Reporting Information [Line Items]
Net sales										$ 171,245	$ 179,223	$ 170,087

[1] Includes replacement part sales to the Company's OEM Customers.