Description of Business and Summary of Significant Accounting Policies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 30, 2011	Apr. 30, 2010	Apr. 30, 2011	Apr. 30, 2010	Jul. 31, 2010	Nov. 02, 2009 Mint Software Inc. [Member]	May 21, 2010 Medfusion Inc. [Member]
Basis of Presentation (Textuals)
Acquisition of companies						$ 170	$ 89
Numerator:
Net income from continuing operations	688	576	691	587
Net income from discontinued operations				35
Net income	$ 688	$ 576	$ 691	$ 622
Shares used in basic per share amounts:
Weighted average common shares outstanding	303	314	309	316
Shares used in diluted per share amounts:
Weighted average common shares outstanding	303	314	309	316
Dilutive common equivalent shares from stock options and restricted stock awards	10	9	10	9
Dilutive weighted average common shares outstanding	313	323	319	325
Basic and diluted net income per share:
Basic net income per share from continuing operations	$ 2.27	$ 1.83	$ 2.23	$ 1.86
Basic net income per share from discontinued operations				$ 0.11
Basic net income per share	$ 2.27	$ 1.83	$ 2.23	$ 1.97
Diluted net income per share from continuing operations	$ 2.20	$ 1.78	$ 2.16	$ 1.80
Diluted net income per share from discontinued operations				$ 0.11
Diluted net income per share	$ 2.20	$ 1.78	$ 2.16	$ 1.91
Weighted average stock options and restricted stock units excluded from calculation due to anti-dilutive effect	1	7		13
Description of Business and Summary of Significant Accounting Policies (Textuals)
Maximum limit of customer accountable for total net revenue	10.00%	10.00%	10.00%	10.00%
Maximum limit of customer accountable for total accounts receivable			10.00%		10.00%