CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income	$ 121.5	$ 99.7
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	50.2	50.6
Amortization	1.6	1.3
Stock-based compensation	13.4	9.4
Non-cash restructuring charges	0.4	0.4
Contingent consideration payments in excess of acquisition-date liability	(0.3)	(0.5)
Other non-cash items, net	(1.3)	(3.4)
Changes in assets and liabilities	(32.8)	(30.5)
Net cash provided by operating activities	152.7	127.0
Cash flows from investing activities:
Capital expenditures	(57.1)	(48.2)
Acquisition of business	(18.9)	0.0
Other, net	0.2	2.5
Net cash used in investing activities	(75.8)	(45.7)
Cash flows from financing activities:
Borrowings under revolving credit agreements	28.0	0.0
Repayments under revolving credit agreements	(28.0)	0.0
Debt issuance costs	(0.9)	0.0
Dividend payments	(22.2)	(20.7)
Proceeds from stock-based compensation awards	16.2	6.5
Employee stock purchase plan contributions	2.6	2.4
Shares purchased under share repurchase programs	(83.1)	(70.8)
Net cash used in financing activities	(87.4)	(82.6)
Effect of exchange rates on cash	(0.2)	(9.1)
Net decrease in cash and cash equivalents	(10.7)	(10.4)
Cash and cash equivalents at beginning of period	337.4	235.9
Cash and cash equivalents at end of period	$ 326.7	$ 225.5