CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Millions, unless otherwise specified	Jul. 31, 2013	Jan. 31, 2013
Current assets [Abstract]:
Cash and cash equivalents	$ 1,401.0	$ 1,612.2
Marketable securities	596.9	342.1
Accounts receivable, net	303.9	495.1
Deferred income taxes	51.6	42.2
Prepaid expenses and other current assets	83.1	60.8
Total current assets	2,436.5	2,552.4
Marketable securities	410.1	411.1
Computer equipment, software, furniture and leasehold improvements, net	133.4	114.9
Purchased technologies, net	63.1	76.0
Goodwill	903.2	871.5
Deferred income taxes, net	125.3	122.8
Other assets	151.7	159.7
Assets, Total	4,223.3	4,308.4
Current liabilities [Abstract]:
Accounts payable	74.4	94.2
Accrued compensation	125.7	189.6
Accrued income taxes	42.5	13.9
Deferred revenue	636.9	647.0
Other accrued liabilities	76.4	99.0
Total current liabilities	955.9	1,043.7
Deferred revenue	168.6	187.6
Long term income taxes payable	203.4	194.2
Long-term Debt	746.0	745.6
Other liabilities	98.3	94.1
Commitments and contingencies
Stockholders' equity [Abstract]:
Preferred stock	0	0
Common stock and additional paid-in capital	1,455.8	1,449.8
Accumulated other comprehensive income	(7.5)	(5.7)
Retained earnings	602.8	599.1
Total stockholders' equity	2,051.1	2,043.2
Liabilities and Equity, Total	$ 4,223.3	$ 4,308.4