Supplemental Guarantor Information - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	$ 376.2	$ 313.1
Cash flows from investing activities:
Capital expenditures	(36.8)	(25.7)
Net cash used in investing activities	(36.8)	(25.7)
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	67.7	105.4
Repayments of borrowings under revolving credit facilities	(13.7)	(105.4)
Repayments of long-term debt	(7.5)	(13.4)
Proceeds from issuance of long-term debt	2,083.0	0.0
Payments to extinguish long-term debt	(2,121.3)	0.0
Payments of debt financing costs	(9.6)	0.0
Net change in accounts payable-inventory financing	(85.1)	71.3
Proceeds from stock option exercises	7.4	3.8
Excess tax benefits from equity-based compensation		0.7
Proceeds from Coworker Stock Purchase Plan	4.7	4.5
Repurchases of common stock	(359.4)	(223.1)
Payment of incentive compensation plan withholding taxes	(42.0)
Dividends	(50.3)	(35.7)
Principal payments under capital lease obligations	(0.6)	(0.8)
Repayment of intercompany loan	0.0
Principal payments under capital lease obligations	(0.6)	(0.8)
Distributions and advances from (to) affiliates	0.0	0.0
Net cash used in financing activities	(526.7)	(192.7)
Effect of exchange rate changes on cash and cash equivalents	2.6	(2.9)
Net (decrease) increase in cash and cash equivalents	(184.7)	91.8
Cash and cash equivalents—beginning of period	263.7	37.6
Cash and cash equivalents—end of period	79.0	129.4
Consolidating Adjustments
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	(33.9)	20.8
Cash flows from investing activities:
Capital expenditures	0.0	0.0
Net cash used in investing activities	0.0	0.0
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	0.0	0.0
Repayments of borrowings under revolving credit facilities	0.0	0.0
Repayments of long-term debt	0.0	0.0
Proceeds from issuance of long-term debt	0.0
Payments to extinguish long-term debt	0.0
Payments of debt financing costs	0.0
Net change in accounts payable-inventory financing	0.0	0.0
Proceeds from stock option exercises	0.0	0.0
Excess tax benefits from equity-based compensation		0.0
Proceeds from Coworker Stock Purchase Plan	0.0	0.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0
Dividends	0.0	0.0
Principal payments under capital lease obligations	0.0	0.0
Repayment of intercompany loan	0.0
Distributions and advances from (to) affiliates	7.4	(3.1)
Net cash used in financing activities	7.4	(3.1)
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net (decrease) increase in cash and cash equivalents	(26.5)	17.7
Cash and cash equivalents—beginning of period	0.0	(39.4)
Cash and cash equivalents—end of period	(26.5)	(21.7)
Parent Guarantor | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	0.0	0.0
Cash flows from investing activities:
Capital expenditures	0.0	0.0
Net cash used in investing activities	0.0	0.0
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	0.0	0.0
Repayments of borrowings under revolving credit facilities	0.0	0.0
Repayments of long-term debt	0.0	0.0
Proceeds from issuance of long-term debt	0.0
Payments to extinguish long-term debt	0.0
Payments of debt financing costs	0.0
Net change in accounts payable-inventory financing	0.0	0.0
Proceeds from stock option exercises	0.0	0.0
Excess tax benefits from equity-based compensation		0.0
Proceeds from Coworker Stock Purchase Plan	0.0	0.0
Repurchases of common stock	(359.4)	(223.1)
Payment of incentive compensation plan withholding taxes	0.0
Dividends	(50.3)	(35.7)
Principal payments under capital lease obligations	0.0	0.0
Repayment of intercompany loan	0.0
Distributions and advances from (to) affiliates	409.7	258.8
Net cash used in financing activities	0.0	0.0
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net (decrease) increase in 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
Subsidiary Issuer | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	(22.1)	(79.4)
Cash flows from investing activities:
Capital expenditures	(26.6)	(22.1)
Net cash used in investing activities	(26.6)	(22.1)
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	54.0	105.4
Repayments of borrowings under revolving credit facilities	0.0	(105.4)
Repayments of long-term debt	(7.5)	(7.7)
Proceeds from issuance of long-term debt	2,083.0
Payments to extinguish long-term debt	(2,121.3)
Payments of debt financing costs	(9.6)
Net change in accounts payable-inventory financing	(1.2)	0.1
Proceeds from stock option exercises	7.4	3.8
Excess tax benefits from equity-based compensation		0.7
Proceeds from Coworker Stock Purchase Plan	4.7	4.5
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	(16.0)
Dividends	0.0	0.0
Principal payments under capital lease obligations	0.0	0.0
Repayment of intercompany loan	0.0
Distributions and advances from (to) affiliates	(100.5)	136.4
Net cash used in financing activities	(107.0)	137.8
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net (decrease) increase in cash and cash equivalents	(155.7)	36.3
Cash and cash equivalents—beginning of period	222.7	45.1
Cash and cash equivalents—end of period	67.0	81.4
Guarantor Subsidiaries | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	391.5	326.3
Cash flows from investing activities:
Capital expenditures	(4.3)	(1.9)
Net cash used in investing activities	(4.3)	(1.9)
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	0.0	0.0
Repayments of borrowings under revolving credit facilities	0.0	0.0
Repayments of long-term debt	0.0	0.0
Proceeds from issuance of long-term debt	0.0
Payments to extinguish long-term debt	0.0
Payments of debt financing costs	0.0
Net change in accounts payable-inventory financing	(83.9)	70.9
Proceeds from stock option exercises	0.0	0.0
Excess tax benefits from equity-based compensation		0.0
Proceeds from Coworker Stock Purchase Plan	0.0	0.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	(24.0)
Dividends	0.0	0.0
Principal payments under capital lease obligations	(0.1)	0.0
Repayment of intercompany loan	(34.3)
Distributions and advances from (to) affiliates	(316.6)	(395.3)
Net cash used in financing activities	(390.3)	(324.4)
Effect of exchange rate changes on cash and cash equivalents	0.0	0.0
Net (decrease) increase in cash and cash equivalents	(3.1)	0.0
Cash and cash equivalents—beginning of period	3.1	0.0
Cash and cash equivalents—end of period	0.0	0.0
Non-Guarantor Subsidiaries | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	40.7	45.4
Cash flows from investing activities:
Capital expenditures	(5.9)	(1.7)
Net cash used in investing activities	(5.9)	(1.7)
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	13.7	0.0
Repayments of borrowings under revolving credit facilities	(13.7)	0.0
Repayments of long-term debt	0.0	(5.7)
Proceeds from issuance of long-term debt	0.0
Payments to extinguish long-term debt	0.0
Payments of debt financing costs	0.0
Net change in accounts payable-inventory financing	0.0	0.3
Proceeds from stock option exercises	0.0	0.0
Excess tax benefits from equity-based compensation		0.0
Proceeds from Coworker Stock Purchase Plan	0.0	0.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	(2.0)
Dividends	0.0	0.0
Principal payments under capital lease obligations	(0.5)	(0.8)
Repayment of intercompany loan	34.3
Distributions and advances from (to) affiliates	0.0	3.2
Net cash used in financing activities	(36.8)	(3.0)
Effect of exchange rate changes on cash and cash equivalents	2.6	(2.9)
Net (decrease) increase in cash and cash equivalents	0.6	37.8
Cash and cash equivalents—beginning of period	37.9	31.9
Cash and cash equivalents—end of period	38.5	69.7
Co-Issuer | Reportable Legal Entities
Supplemental Guarantor Information [Line Items]
Net cash provided by operating activities	0.0	0.0
Cash flows from investing activities:
Capital expenditures	0.0	0.0
Net cash used in investing activities	0.0	0.0
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facilities	0.0	0.0
Repayments of borrowings under revolving credit facilities	0.0	0.0
Repayments of long-term debt	0.0	0.0
Proceeds from issuance of long-term debt	0.0
Payments to extinguish long-term debt	0.0
Payments of debt financing costs	0.0
Net change in accounts payable-inventory financing	0.0	0.0
Proceeds from stock option exercises	0.0	0.0
Excess tax benefits from equity-based compensation		0.0
Proceeds from Coworker Stock Purchase Plan	0.0	0.0
Repurchases of common stock	0.0	0.0
Payment of incentive compensation plan withholding taxes	0.0
Dividends	0.0	0.0
Principal payments under capital lease obligations	0.0	0.0
Repayment of intercompany loan	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 and cash equivalents	0.0	0.0
Net (decrease) increase in 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