Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Operating activities:
Net income	$ 151.5	$ 137.2
Reconciliation of net income to net cash provided by operating activities:
Depreciation	46.3	49.1
Amortization	60.8	63.7
Lease expense	13.5	14.1
Stock-based compensation	8.7	14.9
Loss on extinguishment of debt	0.0	8.8
Deferred taxes	0.7	(1.1)
Other operating activities, net	9.5	11.5
Changes in assets and liabilities, excluding effects of acquisitions:
Receivables	(190.7)	(11.8)
Inventories	(40.6)	(48.4)
Contract assets	13.7	(1.4)
Prepaid expenses and other assets	16.3	29.4
Accounts payable	118.3	(5.0)
Accrued and other current liabilities	(20.9)	(31.8)
Contract liabilities	6.8	11.5
Other long-term liabilities	(22.4)	(14.4)
Net cash provided by operating activities	171.5	226.3
Investing activities:
Capital expenditures	(55.1)	(48.5)
Investment in securities	(10.2)	0.0
Acquisitions, net of cash acquired	0.0	(2.4)
Other investing activities, net	1.8	0.9
Net cash used in investing activities	(63.5)	(50.0)
Financing activities:
Proceeds from notes	0.0	740.7
Repayment of notes	0.0	(258.5)
Borrowings from revolving credit facility	0.0	500.0
Repayments of revolving credit facility	0.0	(500.0)
Financing costs	0.0	(24.2)
Repurchases of common stock	(265.6)	(191.8)
Dividends paid	(56.0)	(56.0)
Proceeds from exercise of stock options	45.6	11.4
Withholding tax paid related to stock-based compensation	(7.7)	(6.4)
Other financing activities, net	(0.8)	(0.5)
Net cash used in financing activities	(284.5)	214.7
Effect of foreign currency exchange rate changes on cash and cash equivalents	(0.3)	(4.5)
Change in cash and cash equivalents	(176.8)	386.5
Less: change in cash and cash equivalents of discontinued operations	7.0	0.9
Cash and cash equivalents at beginning of period	897.1	342.5
Cash and cash equivalents at end of period	$ 713.3	$ 728.1