Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating activities:
Net income	$ 79.4	$ 309.6
Reconciliation of net income to net cash provided by operating activities:
Depreciation	21.3	22.7
Amortization	27.8	28.3
Stock-based compensation, net of tax benefit	6.8	6.8
Deferred taxes	(0.5)	(2.3)
Gain on sale of discontinued operation, net of tax	0.0	(247.9)
Other operating activities, net	8.1	(3.1)
Changes in assets and liabilities, excluding effects of acquisitions:
Receivables	(63.1)	(26.8)
Inventories	(18.6)	(55.8)
Prepaid expenses and other assets	26.0	11.5
Accounts payable	53.4	27.2
Accrued liabilities and other	(31.0)	(40.6)
Deferred revenues	2.8	3.3
Other long-term liabilities	(2.6)	0.3
Net cash provided by operating activities	109.8	33.2
Investing activities:
Acquisitions, net of cash acquired	(202.0)	(0.7)
Capital expenditures	(23.3)	(42.5)
Proceeds from sale of discontinued operation	0.0	754.6
Other investing activities, net	0.9	3.6
Net cash provided by (used in) investing activities	(224.4)	715.0
Financing activities:
Repurchases of common stock	(157.1)	(122.0)
Dividends paid	(23.3)	(23.1)
Proceeds from exercise of stock options	10.6	1.7
Withholding tax paid related to stock-based compensation	(3.3)	(4.6)
Net cash used in financing activities	(173.1)	(148.0)
Effect of foreign currency exchange rate changes on cash and cash equivalents	0.7	1.9
Change in cash and cash equivalents	(287.0)	602.1
Less: change in cash and cash equivalents of discontinued operations	0.0	1.3
Cash and cash equivalents at beginning of period	803.6	378.3
Cash and cash equivalents at beginning of period	$ 516.6	$ 979.1