Stock-Based Compensation Stock Options (Details) (USD $)	3 Months Ended			6 Months Ended
	Jan. 31, 2015	Oct. 31, 2014	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
Additional Disclosures
Targeted annual dividend per share	$ 1.20			$ 1.20
Stock Options
Awards (in Shares)
Outstanding, Beginning Balance	2,229,033	2,132,896		2,132,896
Granted	154,025	253,000
Expired/canceled	(10,800)	(9,900)
Exercised	(137,525)	(146,963)
Outstanding, Ending Balance	2,234,733	2,229,033		2,234,733
Exercisable, Ending Balance	722,743			722,743
Vested and Expected to Vest, Ending Balance	2,063,199			2,063,199
Weighted Average Exercise Price
Outstanding, Beginning Balance	$ 28.94	$ 28.17		$ 28.17
Granted	$ 33.76	$ 33.94
Expired/canceled	$ 29.20	$ 29.10
Exercised	$ 28.06	$ 26.43
Outstanding, Ending Balance	$ 29.32	$ 28.94		$ 29.32
Exercisable, Ending Balance	$ 28.24			$ 28.24
Vested and Expected to Vest, Ending Balance	$ 29.29			$ 29.29
Weighted Average Remaining Contractual Term (Years)
Outstanding, Ending Balance				7 years 2 months 23 days
Exercisable, Ending Balance				5 years 2 months 9 days
Vested And Expected To Vest, Ending Balance				7 years 1 month 28 days
Aggregate Intrinsic Value
Outstanding, Ending Balance	$ 8,645,000			$ 8,645,000
Exercisable, Ending Balance	3,469,000			3,469,000
Vested and Expected to Vest, Ending Balance	7,745,000			7,745,000
Additional Disclosures
Exercise price, lower range limit				$ 24.35
Exercise price, upper range limit				$ 33.94
Total intrinsic value of stock-based awards settled	$ 806,000		$ 391,000	$ 1,959,000	$ 432,000
Contractual term (in years)				10 years	10 years
Vesting period (in years)				5 years	5 years
Vested Stock Based Awards Net Settled Upon Exercise				280,288	0
Stock Issued During The Period, Shares, Net Settlement Of Stock-Based Awards				45,989
Per share weighted average grant date fair value of stock based awards granted	$ 6.46		$ 6.26	$ 6.14	$ 5.50
Fair Value Assumptions
Expected dividend yield	3.55%		3.84%	3.54%	4.03%
Expected volatility	29.98%		32.00%	28.13%	32.85%
Risk-free interest rate	1.36%		1.50%	1.61%	1.39%
Expected life (years)	5 years 5 months 23 days		5 years 3 months 22 days	5 years 5 months 12 days	5 years 5 months 9 days
SARs
Awards (in Shares)
Granted				0	0
Exercised				0	0