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Supplemental Guarantor Information - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by operating activities | $ 602.3 | $ 439.1 |
Cash flows used in investing activities: |  |  |
Capital expenditures | (53.4) | (58.6) |
Net cash used in investing activities | (53.4) | (58.6) |
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facilities | 688.9 | 1,279.1 |
Repayments of borrowings under revolving credit facilities | (681.9) | (1,087.5) |
Repayments of long-term debt | (18.2) | (11.2) |
Proceeds from issuance of long-term debt | 0.0 | 2,083.0 |
Payments to extinguish long-term debt | 0.0 | (2,121.3) |
Payments of debt financing costs | (1.0) | (9.6) |
Net change in accounts payable-inventory financing | (90.1) | (41.4) |
Premium payments on interest rate cap agreements | (12.6) | 0.0 |
Proceeds from stock option exercises | 24.4 | 9.1 |
Proceeds from Coworker Stock Purchase Plan | 8.4 | 7.6 |
Repurchases of common stock | (232.5) | (534.0) |
Payment of incentive compensation plan withholding taxes | (27.1) | (42.0) |
Dividends | (95.5) | (74.7) |
Repayment of intercompany loan | 0.0 | 0.0 |
Other | 1.9 | (4.7) |
Distributions and advances from (to) affiliates | 0.0 | 0.0 |
Net cash used in financing activities | (435.3) | (547.6) |
Effect of exchange rate changes on cash and cash equivalents | (2.7) | 1.3 |
Net increase (decrease) in cash and cash equivalents | 110.9 | (165.8) |
Cash and cash equivalents—beginning of period | 144.2 | 263.7 | $ 263.7
Cash and cash equivalents—end of period | 255.1 | 97.9 | 144.2
Consolidating Adjustments |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by operating activities | (7.4) | (22.0) |
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 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 | 0.0 |
Net change in accounts payable-inventory financing | 0.0 | 0.0 |
Premium payments on interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 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 | 0.0 |
Dividends | 0.0 | 0.0 |
Repayment of intercompany loan | 0.0 | 0.0 |
Other | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | (6.0) | 10.3 |
Net cash used in financing activities | (6.0) | 10.3 |
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 |
Net increase (decrease) in cash and cash equivalents | (13.4) | (11.7) |
Cash and cash equivalents—beginning of period | (1.9) | 0.0 | 0.0
Cash and cash equivalents—end of period | (15.3) | (11.7) | (1.9)
Parent Guarantor | Reportable Legal Entities |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by operating activities | 0.0 | 42.4 |
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 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 | 0.0 |
Net change in accounts payable-inventory financing | 0.0 | 0.0 |
Premium payments on interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 0.0 |
Proceeds from Coworker Stock Purchase Plan | 0.0 | 0.0 |
Repurchases of common stock | (232.5) | (534.0) |
Payment of incentive compensation plan withholding taxes | (27.1) | 0.0 |
Dividends | (95.5) | (74.7) |
Repayment of intercompany loan | 0.0 | 0.0 |
Other | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | 355.1 | 566.3 |
Net cash used in financing activities | 0.0 | (42.4) |
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 |
Net increase (decrease) in 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
Subsidiary Issuer | Reportable Legal Entities |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by operating activities | (78.9) | (17.7) |
Cash flows used in investing activities: |  |  |
Capital expenditures | (40.9) | (40.0) |
Net cash used in investing activities | (40.9) | (40.0) |
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facilities | 640.0 | 1,233.3 |
Repayments of borrowings under revolving credit facilities | (640.0) | (1,057.0) |
Repayments of long-term debt | (11.2) | (11.2) |
Proceeds from issuance of long-term debt |  | 2,083.0 |
Payments to extinguish long-term debt |  | (2,121.3) |
Payments of debt financing costs | (1.0) | (9.6) |
Net change in accounts payable-inventory financing | (0.8) | (1.2) |
Premium payments on interest rate cap agreements | (12.6) |  |
Proceeds from stock option exercises | 24.4 | 9.1 |
Proceeds from Coworker Stock Purchase Plan | 8.4 | 7.6 |
Repurchases of common stock | 0.0 | 0.0 |
Payment of incentive compensation plan withholding taxes | 0.0 | (16.0) |
Dividends | 0.0 | 0.0 |
Repayment of intercompany loan | 0.0 | 0.0 |
Other | 6.6 | 0.2 |
Distributions and advances from (to) affiliates | 213.2 | (202.6) |
Net cash used in financing activities | 227.0 | (85.7) |
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 |
Net increase (decrease) in cash and cash equivalents | 107.2 | (143.4) |
Cash and cash equivalents—beginning of period | 113.7 | 222.7 | 222.7
Cash and cash equivalents—end of period | 220.9 | 79.3 | 113.7
Guarantor Subsidiaries |  |  |
Cash flows used in financing activities: |  |  |
Payments of debt financing costs |  | 0.0 |
Guarantor Subsidiaries | Reportable Legal Entities |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by operating activities | 608.4 | 422.4 |
Cash flows used in investing activities: |  |  |
Capital expenditures | (3.5) | (4.8) |
Net cash used in investing activities | (3.5) | (4.8) |
Cash flows used in 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 | (85.8) | (52.9) |
Premium payments on interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 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 | (24.0) |
Dividends | 0.0 | 0.0 |
Repayment of intercompany loan | 47.5 | 34.3 |
Other | (4.3) | (4.1) |
Distributions and advances from (to) affiliates | (562.3) | (374.0) |
Net cash used in financing activities | (604.9) | (420.7) |
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 |
Net increase (decrease) in cash and cash equivalents | 0.0 | (3.1) |
Cash and cash equivalents—beginning of period | 0.0 | 3.1 | 3.1
Cash and cash equivalents—end of period | 0.0 | 0.0 | 0.0
Non-Guarantor Subsidiaries | Reportable Legal Entities |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by operating activities | 80.2 | 14.0 |
Cash flows used in investing activities: |  |  |
Capital expenditures | (9.0) | (13.8) |
Net cash used in investing activities | (9.0) | (13.8) |
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facilities | 48.9 | 45.8 |
Repayments of borrowings under revolving credit facilities | (41.9) | (30.5) |
Repayments of long-term debt | (7.0) | 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 | 0.0 |
Net change in accounts payable-inventory financing | (3.5) | 12.7 |
Premium payments on interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 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 | (2.0) |
Dividends | 0.0 | 0.0 |
Repayment of intercompany loan | (47.5) | (34.3) |
Other | (0.4) | (0.8) |
Distributions and advances from (to) affiliates | 0.0 | 0.0 |
Net cash used in financing activities | (51.4) | (9.1) |
Effect of exchange rate changes on cash and cash equivalents | (2.7) | 1.3 |
Net increase (decrease) in cash and cash equivalents | 17.1 | (7.6) |
Cash and cash equivalents—beginning of period | 32.4 | 37.9 | 37.9
Cash and cash equivalents—end of period | 49.5 | 30.3 | 32.4
Co-Issuer | 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 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 | 0.0 |
Net change in accounts payable-inventory financing | 0.0 | 0.0 |
Premium payments on interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 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 | 0.0 |
Dividends | 0.0 | 0.0 |
Repayment of intercompany loan | 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 and cash equivalents | 0.0 | 0.0 |
Net increase (decrease) in 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

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