CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Millions, unless otherwise specified	Jul. 31, 2012	Jan. 31, 2012
Current assets [Abstract]:
Cash and cash equivalents	$ 930.2	$ 1,156.9
Marketable securities	500.5	254.4
Accounts receivable, net	361.4	395.1
Deferred income taxes	44.8	30.1
Prepaid expenses and other current assets	65.8	59.4
Total current assets	1,902.7	1,895.9
Marketable securities	286.1	192.8
Computer equipment, software, furniture and leasehold improvements, net	109.0	104.5
Purchased technologies, net	71.4	84.6
Goodwill	739.2	682.4
Deferred income taxes, net	136.8	135.8
Other assets	130.7	131.8
Assets, Total	3,375.9	3,227.8
Current liabilities [Abstract]:
Accounts payable	82.9	89.3
Accrued compensation	136.6	183.9
Accrued income taxes	17.0	14.4
Deferred revenue	590.9	582.3
Other accrued liabilities	74.0	84.2
Total current liabilities	901.4	954.1
Deferred revenue	161.1	136.9
Long term income taxes payable	179.0	174.8
Other liabilities	83.1	79.1
Stockholders' equity [Abstract]:
Preferred stock	0	0
Common stock and additional paid-in capital	1,457.3	1,365.4
Accumulated other comprehensive income	0.6	5.9
Retained earnings	593.4	511.6
Total stockholders' equity	2,051.3	1,882.9
Liabilities and Equity, Total	$ 3,375.9	$ 3,227.8