CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2016	Apr. 30, 2015
Operating activities:
Net (loss) income	$ (173.0)	$ 19.1
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation, amortization and accretion	37.4	37.8
Stock-based compensation expense	56.9	50.2
Deferred income taxes	6.2	(5.3)
Restructuring charges and other facility exit costs, net	52.3	0.0
Other operating activities	8.3	(3.5)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	397.4	143.1
Prepaid expenses and other current assets	(14.9)	(22.4)
Accounts payable and accrued liabilities	(197.2)	(110.8)
Deferred revenue	4.1	(3.4)
Accrued income taxes	(13.1)	(18.3)
Net cash provided by operating activities	164.4	86.5
Investing activities:
Purchases of marketable securities	(577.5)	(485.2)
Sales of marketable securities	107.6	97.5
Maturities of marketable securities	322.6	192.4
Capital expenditures	(22.3)	(12.5)
Acquisitions, net of cash acquired	(59.6)	(34.5)
Other investing activities	(1.0)	(10.6)
Net cash (used in) investing activities	(230.2)	(252.9)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	51.2	57.2
Taxes paid related to net share settlement of equity awards	(18.3)	(23.1)
Repurchases of common stock	(100.1)	(95.4)
Net cash (used in) financing activities	(67.2)	(61.3)
Effect of exchange rate changes on cash and cash equivalents	3.4	(0.2)
Net (decrease) in cash and cash equivalents	(129.6)	(227.9)
Cash and cash equivalents at beginning of period	1,353.0	1,410.6
Cash and cash equivalents at end of period	$ 1,223.4	$ 1,182.7