Supplemental Guarantor Information - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	$ 252.4	$ 222.2
Cash flows used in investing activities:
Capital expenditures	(19.4)	(15.9)
Acquisition of business, net of cash acquired	(68.7)	0.0
Net cash used in investing activities	(88.1)	(15.9)
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	88.5	170.0
Repayments of borrowings under revolving credit facility	(12.5)	(170.0)
Repayments of long-term debt	(5.9)	(3.7)
Net change in accounts payable-inventory financing	70.2	24.9
Repurchases of common stock	(177.1)	(109.2)
Payment of incentive compensation plan withholding taxes	(11.6)	(8.7)
Dividend payments	(43.4)	(32.0)
Capital contributions	0.0
Other	11.6	(2.5)
Distributions and advances from (to) affiliates	0.0	0.0
Net cash used in financing activities	(80.2)	(131.2)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.8	1.7
Net increase in cash, cash equivalents and restricted cash	84.9	76.8
Cash, cash equivalents and restricted cash—beginning of period	205.8	144.2
Cash, cash equivalents and restricted cash—end of period	290.7	221.0
Consolidating Adjustments
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	1.1	(14.4)
Cash flows used in investing activities:
Capital expenditures	0.0	0.0
Acquisition of business, net of cash acquired	0.0
Net cash used in investing activities	0.0	0.0
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	0.0	0.0
Repayments of borrowings under revolving credit facility	0.0	0.0
Repayments of long-term debt	0.0	0.0
Net change in accounts payable-inventory financing	0.0	0.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0	0.0
Dividend payments	0.0	0.0
Capital contributions	0.0
Other	0.0	0.0
Distributions and advances from (to) affiliates	7.8	(1.9)
Net cash used in financing activities	7.8	(1.9)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.0	0.0
Net increase in cash, cash equivalents and restricted cash	8.9	(16.3)
Cash, cash equivalents and restricted cash—beginning of period	(16.9)	(1.9)
Cash, cash equivalents and restricted cash—end of period	(8.0)	(18.2)
Parent Guarantor
Cash flows used in investing activities:
Acquisition of business, net of cash acquired	0.0
Parent Guarantor \| Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	0.0	0.0
Cash flows used in investing activities:
Capital expenditures	0.0	0.0
Net cash used in investing activities	0.0	0.0
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	0.0	0.0
Repayments of borrowings under revolving credit facility	0.0	0.0
Repayments of long-term debt	0.0	0.0
Net change in accounts payable-inventory financing	0.0	0.0
Repurchases of common stock	(177.1)	(109.2)
Payment of incentive compensation plan withholding taxes	(11.6)	(8.7)
Dividend payments	(43.4)	(32.0)
Capital contributions	0.0
Other	0.0	0.0
Distributions and advances from (to) affiliates	232.1	149.9
Net cash used in financing activities	0.0	0.0
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.0	0.0
Net increase in cash, cash equivalents and restricted cash	0.0	0.0
Cash, cash equivalents and restricted cash—beginning of period	0.0	0.0
Cash, cash equivalents and restricted cash—end of period	0.0	0.0
Subsidiary Issuer
Cash flows used in investing activities:
Acquisition of business, net of cash acquired	0.0
Subsidiary Issuer \| Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	16.9	(13.8)
Cash flows used in investing activities:
Capital expenditures	(13.0)	(11.1)
Net cash used in investing activities	(13.0)	(11.1)
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	88.5	163.0
Repayments of borrowings under revolving credit facility	(12.5)	(163.0)
Repayments of long-term debt	(3.7)	(3.7)
Net change in accounts payable-inventory financing	0.1	(0.9)
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0	0.0
Dividend payments	0.0	0.0
Capital contributions	(76.0)
Other	11.6	(2.2)
Distributions and advances from (to) affiliates	7.3	91.3
Net cash used in financing activities	15.3	84.5
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.0	0.0
Net increase in cash, cash equivalents and restricted cash	19.2	59.6
Cash, cash equivalents and restricted cash—beginning of period	176.0	113.7
Cash, cash equivalents and restricted cash—end of period	195.2	173.3
Guarantor Subsidiaries
Cash flows used in investing activities:
Acquisition of business, net of cash acquired	0.0
Guarantor Subsidiaries \| Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	183.2	239.6
Cash flows used in investing activities:
Capital expenditures	(4.6)	(1.2)
Net cash used in investing activities	(4.6)	(1.2)
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	0.0	0.0
Repayments of borrowings under revolving credit facility	0.0	0.0
Repayments of long-term debt	0.0	0.0
Net change in accounts payable-inventory financing	68.6	1.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0	0.0
Dividend payments	0.0	0.0
Capital contributions	0.0
Other	0.0	(0.1)
Distributions and advances from (to) affiliates	(247.2)	(239.3)
Net cash used in financing activities	(178.6)	(238.4)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.0	0.0
Net increase in cash, cash equivalents and restricted cash	0.0	0.0
Cash, cash equivalents and restricted cash—beginning of period	0.0	0.0
Cash, cash equivalents and restricted cash—end of period	0.0	0.0
Non-Guarantor Subsidiaries
Cash flows used in investing activities:
Acquisition of business, net of cash acquired	(68.7)
Non-Guarantor Subsidiaries \| Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	51.2	10.8
Cash flows used in investing activities:
Capital expenditures	(1.8)	(3.6)
Net cash used in investing activities	(70.5)	(3.6)
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	0.0	7.0
Repayments of borrowings under revolving credit facility	0.0	(7.0)
Repayments of long-term debt	(2.2)	0.0
Net change in accounts payable-inventory financing	1.5	24.8
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0	0.0
Dividend payments	0.0	0.0
Capital contributions	76.0
Other	0.0	(0.2)
Distributions and advances from (to) affiliates	0.0	0.0
Net cash used in financing activities	75.3	24.6
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.8	1.7
Net increase in cash, cash equivalents and restricted cash	56.8	33.5
Cash, cash equivalents and restricted cash—beginning of period	46.7	32.4
Cash, cash equivalents and restricted cash—end of period	103.5	65.9
Affiliated Entity
Cash flows used in investing activities:
Acquisition of business, net of cash acquired	0.0
Affiliated Entity \| Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	0.0	0.0
Cash flows used in investing activities:
Capital expenditures	0.0	0.0
Net cash used in investing activities	0.0	0.0
Cash flows used in financing activities:
Proceeds from borrowings under revolving credit facility	0.0	0.0
Repayments of borrowings under revolving credit facility	0.0	0.0
Repayments of long-term debt	0.0	0.0
Net change in accounts payable-inventory financing	0.0	0.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0	0.0
Dividend payments	0.0	0.0
Other	0.0	0.0
Distributions and advances from (to) affiliates	0.0	0.0
Net cash used in financing activities	0.0	0.0
Effect of exchange rate changes on cash, cash equivalents and restricted cash	0.0	0.0
Net increase in cash, cash equivalents and restricted cash	0.0	0.0
Cash, cash equivalents and restricted cash—beginning of period	0.0	0.0
Cash, cash equivalents and restricted cash—end of period	0.0	$ 0.0
Co-Issuer [Member] \| Reportable Legal Entities
Cash flows used in financing activities:
Capital contributions	$ 0.0

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