CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jul. 31, 2016	Jul. 31, 2015
Operating activities:
Net loss	$ (265.9)	$ (249.5)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, amortization and accretion	70.4	74.0
Stock-based compensation expense	105.9	90.9
Deferred income taxes	(9.2)	223.0
Restructuring charges and other facility exit costs, net	68.3	0.0
Other operating activities	(6.2)	(15.3)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	346.9	64.4
Prepaid expenses and other current assets	(23.3)	(19.4)
Accounts payable and accrued liabilities	(44.6)	(80.3)
Deferred revenue	(1.4)	79.2
Accrued income taxes	(94.5)	(3.3)
Net cash provided by operating activities	146.4	163.7
Investing activities:
Purchases of marketable securities	(810.9)	(1,314.2)
Sales of marketable securities	354.7	187.0
Maturities of marketable securities	791.3	541.0
Capital expenditures	(42.6)	(29.8)
Acquisitions, net of cash acquired	(85.2)	(37.5)
Other investing activities	(6.7)	(13.1)
Net cash provided by (used in) investing activities	200.6	(666.6)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	54.2	61.9
Taxes paid related to net share settlement of equity awards	(19.9)	(28.7)
Repurchases of common stock	(270.0)	(207.7)
Proceeds from debt, net of discount	0.0	748.3
Other financing activities	0.0	(6.3)
Net cash (used in) provided by financing activities	(235.7)	567.5
Effect of exchange rate changes on cash and cash equivalents	3.0	(2.1)
Net increase in cash and cash equivalents	114.3	62.5
Cash and cash equivalents at beginning of period	1,353.0	1,410.6
Cash and cash equivalents at end of period	$ 1,467.3	$ 1,473.1