CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2019	Jan. 31, 2019	Jul. 31, 2018	Apr. 30, 2018
Operating activities:
Net loss	$ (24.2)	$ 64.7	$ (39.4)	$ (82.4)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation, amortization and accretion	32.7			24.1
Stock-based compensation expense	75.2			54.4
Deferred income taxes	24.4			13.3
Restructuring and other exit costs, net	0.2			22.5
Other operating activities	15.3			10.5
Changes in operating assets and liabilities
Accounts receivable	206.2			231.4
Prepaid expenses and other current assets	11.4			(1.4)
Accounts payable and accrued liabilities	(172.6)			(227.7)
Deferred revenue	62.2			(58.5)
Accrued income taxes	(9.6)			(3.1)
Net cash provided by (used in) operating activities	221.2			(16.9)
Investing activities:
Purchases of marketable securities	(19.8)			(9.9)
Sales of marketable securities	4.6			6.2
Maturities of marketable securities	0.0			68.6
Capital expenditures	(14.7)			(16.7)
Other investing activities	0.7			(0.6)
Net cash (used in) provided by investing activities	(29.2)			47.6
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	46.9			49.1
Taxes paid related to net share settlement of equity awards	(25.8)			(38.8)
Repurchases of common stock	(88.5)			(22.0)
Repayment of debt	(125.0)			0.0
Net cash used in financing activities	(192.4)			(11.7)
Effect of exchange rate changes on cash and cash equivalents	(2.4)			(4.0)
Net (decrease) increase in cash and cash equivalents	(2.8)			15.0
Cash and cash equivalents at beginning of period	886.0		$ 1,093.0	1,078.0
Cash and cash equivalents at end of period	$ 883.2	$ 886.0		$ 1,093.0