CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Apr. 30, 2012	Apr. 30, 2011
Operating activities:
Net income	$ 78.9	$ 69.3
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	29.2	24.5
Stock-based compensation expense	33.4	25.9
Excess tax benefits from stock-based compensation	(9.9)	0
Changes in operating assets and liabilities, net of business combinations	7.7	8.7
Net cash provided by operating activities	139.3	128.4
Investing activities:
Purchases of marketable securities	(447.8)	(169.7)
Sales of marketable securities	48.8	34.6
Maturities of marketable securities	128.5	96.5
Capital expenditures	(11.5)	(23.2)
Acquisitions, net of cash acquired	0	(76.4)
Other investing activities	(5.0)	(14.5)
Net cash used in investing activities	(287.0)	(152.7)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	153.0	111.3
Repurchases of common stock	(99.2)	(68.6)
Excess tax benefits from stock-based compensation	9.9	0
Net cash used in financing activities	63.7	42.7
Effect of exchange rate changes on cash and cash equivalents	1.6	(2.1)
Net increase in cash and cash equivalents	(82.4)	16.3
Cash and cash equivalents at beginning of fiscal year	1,156.9	1,075.1
Cash and cash equivalents at end of period	$ 1,074.5	$ 1,091.4

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).