Condensed Consolidating Financial Statements (Statements of Cash Flows) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	$ (141.0)	$ (83.5)
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.3	0.1
Purchases of property, plant and equipment	(37.2)	(22.7)
Net proceeds from sale of business and related property	43.6	0.0
Insurance recoveries received for property damage incurred from natural disaster	6.9	0.0
Net cash used in investing activities	13.6	(22.6)
Cash flows from financing activities:
Short-term borrowings, net	0.0	(0.1)
Asset securitization payments	(43.5)	(51.0)
Long-term debt payments	(31.7)	(10.2)
Long-term borrowings	3.3	0.0
Borrowings from credit facility	844.5	790.0
Payments on credit facility	(525.5)	(444.1)
Proceeds from employee stock purchases	0.8	0.8
Repurchases of common stock	(100.0)	(150.0)
Repurchases of common stock to satisfy employee withholding tax obligations	(13.5)	(18.1)
Intercompany debt	0.0	0.0
Intercompany financing activity	0.0	0.0
Cash dividends paid	(25.5)	(21.3)
Net cash provided by financing activities	108.9	96.0
Decrease in cash and cash equivalents	(18.5)	(10.1)
Effect of exchange rates on cash and cash equivalents	3.9	(1.0)
Cash and cash equivalents, beginning of period	46.3	68.2	$ 68.2
Cash and cash equivalents, end of period	31.7	57.1	46.3
Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	0.0	0.0
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
Asset securitization payments	0.0	0.0
Long-term debt payments	0.0	0.0
Long-term borrowings	0.0
Borrowings from credit facility	0.0	0.0
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	0.0
Cash dividends paid	0.0	0.0
Net cash provided by financing activities	0.0	0.0
Decrease 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	0.0
Cash and cash equivalents, end of period	0.0	0.0	0.0
Parent [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	49.9	104.4
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
Net cash used in investing activities	0.0	0.0
Cash flows from financing activities:
Short-term borrowings, net		0.0
Asset securitization payments		0.0
Long-term debt payments	(30.0)	(7.5)
Long-term borrowings	0.0
Borrowings from credit facility	844.5	790.0
Payments on credit facility	(525.5)	(444.1)
Proceeds from employee stock purchases	0.8	0.8
Repurchases of common stock	(100.0)	(150.0)
Repurchases of common stock to satisfy employee withholding tax obligations	(13.5)	(18.1)
Intercompany debt	(7.9)	(47.5)
Intercompany financing activity	(192.6)	(206.9)
Cash dividends paid	(25.5)	(21.3)
Net cash provided by financing activities	(49.7)	(104.6)
Decrease in cash and cash equivalents	0.2	(0.2)
Effect of exchange rates on cash and cash equivalents	0.0	0.0
Cash and cash equivalents, beginning of period	1.8	1.6	1.6
Cash and cash equivalents, end of period	2.0	1.4	1.8
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	(258.3)	(158.6)
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.3	0.0
Purchases of property, plant and equipment	(33.5)	(17.3)
Net proceeds from sale of business and related property	43.0
Insurance recoveries received for property damage incurred from natural disaster	6.9
Net cash used in investing activities	16.7	(17.3)
Cash flows from financing activities:
Short-term borrowings, net		0.0
Asset securitization payments		0.0
Long-term debt payments	(0.5)	(2.7)
Long-term borrowings	2.7
Borrowings from credit facility		0.0
Payments on credit facility		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	(0.2)	37.9
Intercompany financing activity	237.2	127.7
Cash dividends paid	0.0	0.0
Net cash provided by financing activities	239.2	162.9
Decrease in cash and cash equivalents	(2.4)	(13.0)
Effect of exchange rates on cash and cash equivalents	0.0	0.0
Cash and cash equivalents, beginning of period	15.4	28.0	28.0
Cash and cash equivalents, end of period	13.0	15.0	15.4
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash flows from operating activities	67.4	(29.3)
Cash flows from investing activities:
Proceeds from the disposal of property, plant and equipment	0.0	0.1
Purchases of property, plant and equipment	(3.7)	(5.4)
Net proceeds from sale of business and related property	0.6
Insurance recoveries received for property damage incurred from natural disaster	0.0
Net cash used in investing activities	(3.1)	(5.3)
Cash flows from financing activities:
Short-term borrowings, net		(0.1)
Asset securitization payments	(43.5)	(51.0)
Long-term debt payments	(1.2)	0.0
Long-term borrowings	0.6
Borrowings from credit facility		0.0
Payments on credit facility		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	8.1	9.6
Intercompany financing activity	(44.6)	79.2
Cash dividends paid	0.0	0.0
Net cash provided by financing activities	(80.6)	37.7
Decrease in cash and cash equivalents	(16.3)	3.1
Effect of exchange rates on cash and cash equivalents	3.9	(1.0)
Cash and cash equivalents, beginning of period	29.1	38.6	38.6
Cash and cash equivalents, end of period	$ 16.7	$ 40.7	$ 29.1