Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating activities:
Net income	$ 81.1	$ 70.1
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	37.5	33.1
Stock-based compensation expense	5.5	5.4
Deferred income taxes	(8.0)	8.4
Changes in operating assets and liabilities	(61.0)	(37.4)
Net cash provided by operating activities	55.1	79.6
Investing activities:
Purchases of properties and equipment	(12.5)	(24.3)
Proceeds from sales of properties and equipment	0.2	0.5
Payments for acquisition-related activity, net of cash acquired	(52.2)	(6.2)
Proceeds from acquisition-related activity	0.0	0.8
Net cash used for investing activities	(64.5)	(29.2)
Financing activities:
Increase in revolving lines of credit, net	40.1	20.5
Purchases of treasury stock	(3.4)	(13.7)
Redemptions of common stock to satisfy withholding taxes related to stock-based compensation	(7.8)	(9.0)
Cash dividends paid to stockholders	(16.5)	(14.5)
Proceeds from stock-based compensation activity	4.1	0.6
Other, net	(0.1)	0.1
Net cash provided by (used for) financing activities	16.4	(16.0)
Effects of foreign exchange rate changes on cash and cash equivalents	(0.7)	0.2
Increase in cash and cash equivalents	6.3	34.6
Cash and cash equivalents at beginning of year	81.7	31.6
Cash and cash equivalents at end of period	$ 88.0	$ 66.2