Condensed Consolidating Financial Statements (Statements of Cash Flows) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	$ 231.3	$ 129.0
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.1	0.2
Purchases of property, plant and equipment	(60.9)	(60.5)
Net proceeds from sale of business and related property	115.9	0.0
Insurance recoveries received for property damage incurred from natural disaster	4.2	0.0
Net cash used in investing activities	59.3	(60.3)
Cash flows from financing activities:
Short-term borrowings, net	(1.5)	(1.4)
Asset securitization borrowings	155.0	275.0
Asset securitization payments	(53.7)	0.0
Long-term debt payments	(32.9)	(200.8)
Long-term borrowings	0.0	0.0
Borrowings from credit facility	1,820.0	1,883.0
Payments on credit facility	(1,766.5)	(1,701.0)
Proceeds from employee stock purchases	2.5	2.3
Repurchases of common stock	(350.2)	(250.0)
Repurchases of common stock to satisfy employee withholding tax obligations	(21.1)	(16.0)
Intercompany debt	0.0	0.0
Intercompany financing activity	0.0	0.0
Cash dividends paid	(68.2)	(58.4)
Net cash provided by financing activities	(316.6)	(67.3)
(Decrease) increase in cash and cash equivalents	(26.0)	1.4
Effect of exchange rates on cash and cash equivalents	3.9	9.1
Cash and cash equivalents, beginning of period	68.2	50.2
Cash and cash equivalents, end of period	46.1	60.7
Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	0.0	(0.6)
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.0	0.1
Purchases of property, plant and equipment	0.0	0.0
Net proceeds from sale of business and related property	0.0
Insurance recoveries received for property damage incurred from natural disaster	0.0
Net cash used in investing activities	0.0	0.1
Cash flows from financing activities:
Short-term borrowings, net	0.0	0.0
Asset securitization borrowings	0.0	0.0
Asset securitization payments	0.0	0.0
Long-term debt payments	0.0	(0.5)
Long-term borrowings	0.0	0.0
Borrowings from credit facility	0.0	0.4
Payments on credit facility	0.0	0.0
Proceeds from employee stock purchases	0.0	0.0
Repurchases of common stock	0.0	0.0
Repurchases of common stock to satisfy employee withholding tax obligations	0.0	0.0
Intercompany debt	0.0	0.0
Intercompany financing activity	0.0	0.6
Cash dividends paid	0.0	0.0
Net cash provided by financing activities	0.0	0.5
(Decrease) increase in cash and cash equivalents	0.0	0.0
Effect of exchange rates on cash and cash equivalents	0.0	0.0
Cash and cash equivalents, beginning of period	0.0	0.0
Cash and cash equivalents, end of period	0.0	0.0
Parent [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	57.2	411.6
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.0	0.0
Purchases of property, plant and equipment	0.0	0.0
Net proceeds from sale of business and related property	0.0
Insurance recoveries received for property damage incurred from natural disaster	0.0
Net cash used in investing activities	0.0	0.0
Cash flows from financing activities:
Short-term borrowings, net	0.0	0.0
Asset securitization borrowings	0.0	0.0
Asset securitization payments	0.0	0.0
Long-term debt payments	(30.0)	(200.0)
Long-term borrowings	0.0	0.0
Borrowings from credit facility	1,820.0	1,883.0
Payments on credit facility	(1,766.5)	(1,701.0)
Proceeds from employee stock purchases	2.5	2.3
Repurchases of common stock	(350.2)	(250.0)
Repurchases of common stock to satisfy employee withholding tax obligations	(21.1)	(16.0)
Intercompany debt	(29.8)	102.8
Intercompany financing activity	385.9	(174.3)
Cash dividends paid	(68.2)	(58.4)
Net cash provided by financing activities	(57.4)	(411.6)
(Decrease) increase in cash and cash equivalents	(0.2)	0.0
Effect of exchange rates on cash and cash equivalents	0.0	0.0
Cash and cash equivalents, beginning of period	1.6	1.2
Cash and cash equivalents, end of period	1.4	1.2
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	362.5	(2.4)
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.0	0.1
Purchases of property, plant and equipment	(46.1)	(48.3)
Net proceeds from sale of business and related property	4.0
Insurance recoveries received for property damage incurred from natural disaster	4.2
Net cash used in investing activities	(37.9)	(48.2)
Cash flows from financing activities:
Short-term borrowings, net	0.0	0.0
Asset securitization borrowings	0.0	0.0
Asset securitization payments	0.0	0.0
Long-term debt payments	(2.8)	(0.2)
Long-term borrowings	0.0	(0.1)
Borrowings from credit facility	0.0	(0.2)
Payments on credit facility	0.0	0.0
Proceeds from employee stock purchases	0.0	0.0
Repurchases of common stock	0.0	0.0
Repurchases of common stock to satisfy employee withholding tax obligations	0.0	0.0
Intercompany debt	83.3	(34.8)
Intercompany financing activity	(406.3)	91.0
Cash dividends paid	0.0	0.0
Net cash provided by financing activities	(325.8)	55.9
(Decrease) increase in cash and cash equivalents	(1.2)	5.3
Effect of exchange rates on cash and cash equivalents	(2.8)	0.0
Cash and cash equivalents, beginning of period	28.0	17.1
Cash and cash equivalents, end of period	24.0	22.4
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	(188.4)	(279.6)
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.1	0.0
Purchases of property, plant and equipment	(14.8)	(12.2)
Net proceeds from sale of business and related property	111.9
Insurance recoveries received for property damage incurred from natural disaster	0.0
Net cash used in investing activities	97.2	(12.2)
Cash flows from financing activities:
Short-term borrowings, net	(1.5)	(1.4)
Asset securitization borrowings	155.0	275.0
Asset securitization payments	(53.7)	0.0
Long-term debt payments	(0.1)	(0.1)
Long-term borrowings	0.0	0.1
Borrowings from credit facility	0.0	(0.2)
Payments on credit facility	0.0	0.0
Proceeds from employee stock purchases	0.0	0.0
Repurchases of common stock	0.0	0.0
Repurchases of common stock to satisfy employee withholding tax obligations	0.0	0.0
Intercompany debt	(53.5)	(68.0)
Intercompany financing activity	20.4	82.7
Cash dividends paid	0.0	0.0
Net cash provided by financing activities	66.6	287.9
(Decrease) increase in cash and cash equivalents	(24.6)	(3.9)
Effect of exchange rates on cash and cash equivalents	6.7	9.1
Cash and cash equivalents, beginning of period	38.6	31.9
Cash and cash equivalents, end of period	$ 20.7	$ 37.1