Stock-Based Compensation Stock Options (Details) (USD $)	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Additional Disclosures
Targeted annual dividend per share	$ 1.20	$ 1.10	$ 1.10
Stock options [Member]
Additional Disclosures
Exercise price, lower range limit	$ 13.19
Exercise price, upper range limit	$ 34.15
Total intrinsic value relating to stock-based awards exercised during the period	$ 6,464,000	$ 1,272,000	$ 1,654,000
Vested stock-based awards net settled upon exercise (in shares)	618,970	0	0
Common stock issued for net settlement of stock-based awards (in shares)	79,890	0	0
Per share weighted average grant date fair value of stock based awards granted	$ 5.35	$ 4.45	$ 6.53
Fair Value Assumptions
Expected dividend yield	3.94%	4.22%	3.76%
Expected volatility	30.36%	30.09%	36.63%
Risk-free interest rate	1.47%	1.02%	0.64%
Expected life (years)	5 years 3 months 26 days	5 years 4 months 21 days	5 years 3 months 15 days
Stock options [Member] | Stock-based Awards with Five Year Contractual Term [Member]
Additional Disclosures
Contractual term (in years)	5 years	5 years	5 years
Vesting period (in years)	3 years	3 years	3 years
Stock options [Member] | Stock-based Awards with Ten Year Contractual Term [Member]
Additional Disclosures
Contractual term (in years)	10 years	10 years	10 years
Vesting period (in years)	5 years	5 years	5 years
Stock appreciation rights (SARs) [Member]
Awards (In Shares)
Granted	0	0	0
Exercised	(7,000)	0	0
Additional Disclosures
Total intrinsic value relating to stock-based awards exercised during the period	18,000
Stock Options (Including SARs) [Member]
Awards (In Shares)
Outstanding, Beginning Balance	3,047,910	3,458,403	3,580,168
Granted	458,110	296,525	423,528
Expired/canceled	(492,060)	(616,135)	(390,148)
Exercised	(881,064)	(90,883)	(155,145)
Outstanding, Ending Balance	2,132,896	3,047,910	3,458,403
Exercisable, Ending Balance	949,254
Vested and Expected to Vest, Ending Balance	2,070,258
Weighted Average Exercise Price (Per Share)
Outstanding, Beginning Balance	$ 29.94	$ 31.61	$ 31.86
Granted	$ 29.14	$ 26.07	$ 29.24
Expired/canceled	$ 42.90	$ 39.96	$ 35.71
Exercised	$ 26.55	$ 13.01	$ 20.64
Outstanding, Ending Balance	$ 28.17	$ 29.94	$ 31.61
Exercisable, Ending Balance	$ 27.99
Vested and Expected to Vest, Ending Balance	$ 28.17
Weighted Average Remaining Contractual Term (Years)
Outstanding, Ending Balance	6 years 8 months 19 days
Exercisable, Ending Balance	4 years 10 months 28 days
Vested And Expected To Vest, Ending Balance	6 years 8 months 9 days
Aggregated Intrinsic Value
Outstanding, Ending Balance	12,003,000
Exercisable, Ending Balance	5,519,000
Vested and Expected to Vest, Ending Balance	$ 11,664,000