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Supplemental Guarantor Information - Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | $ 777.7 | $ 604.0 | $ 277.5
Cash flows used in investing activities: |  |  |
Capital expenditures | (81.1) | (63.5) | (90.1)
Premium payments on interest rate cap agreements | 0.0 | (2.4) | (0.5)
Acquisition of business, net of cash acquired | 0.0 | 0.0 | (263.8)
Net cash used in investing activities | (81.1) | (65.9) | (354.4)
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 1,560.7 | 338.8 | 314.5
Repayments of borrowings under revolving credit facility | (1,560.7) | (338.8) | (314.5)
Repayments of long-term debt | (14.9) | (20.6) | (32.8)
Proceeds from issuance of long-term debt | 2,083.0 | 1,483.0 | 525.0
Payments to extinguish long-term debt | (2,121.3) | (1,490.4) | (525.3)
Net change in other long-term obligation | (3.8) | 15.7 | 0.0
Payment of debt financing costs | (9.6) | (5.9) | (6.8)
Net change in accounts payable-inventory financing | (84.0) | 143.6 | 95.9
Effective portion of interest rate cap agreements | 0.4 | 0.0 | 0.0
Proceeds from stock option exercises | 13.0 | 7.4 | 2.4
Proceeds from Coworker Stock Purchase Plan | 10.3 | 9.3 | 8.7
Repurchases of common stock | (534.0) | (367.4) | (241.3)
Payment of incentive compensation plan withholding taxes | (49.6) | 0.0 | (0.6)
Dividends | (106.9) | (78.7) | (52.9)
Principal payments under capital lease obligations | (1.3) | (0.6) |
Repayment of intercompany loan | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | 0.0 | 0.0 | 0.0
Net cash (used in) provided by financing activities | (818.7) | (304.6) | (226.5)
Effect of exchange rate changes on cash and cash equivalents | 2.6 | (7.4) | (3.5)
Net (decrease) increase in cash and cash equivalents | (119.5) | 226.1 | (306.9)
Cash and cash equivalents – beginning of period | 263.7 | 37.6 | 344.5
Cash and cash equivalents – end of period | 144.2 | 263.7 | 37.6
Reportable Legal Entities | Parent Guarantor |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | 0.6 | 0.0 | 0.5
Cash flows used in investing activities: |  |  |
Capital expenditures | 0.0 | 0.0 | 0.0
Premium payments on interest rate cap agreements |  | 0.0 | 0.0
Acquisition of business, net of cash acquired |  |  | 0.0
Net cash used in investing activities | 0.0 | 0.0 | 0.0
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of long-term debt | 0.0 | 0.0 | 0.0
Proceeds from issuance of long-term debt | 0.0 | 0.0 | 0.0
Payments to extinguish long-term debt | 0.0 | 0.0 | 0.0
Net change in other long-term obligation | 0.0 | 0.0 |
Payment of debt financing costs | 0.0 | 0.0 | 0.0
Net change in accounts payable-inventory financing | 0.0 | 0.0 | 0.0
Effective portion of interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 0.0 | 0.0
Proceeds from Coworker Stock Purchase Plan | 0.0 | 0.0 | 0.0
Repurchases of common stock | (534.0) | (367.4) | (241.3)
Payment of incentive compensation plan withholding taxes | (49.6) |  | 0.0
Dividends | (106.9) | (78.7) | (52.9)
Principal payments under capital lease obligations | 0.0 | 0.0 |
Repayment of intercompany loan | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | 689.9 | 446.1 | 293.7
Net cash (used in) provided by financing activities | (0.6) | 0.0 | (0.5)
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 | 0.0
Net (decrease) increase in cash and cash equivalents | 0.0 | 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
Reportable Legal Entities | Subsidiary Issuer |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | (71.1) | (158.5) | (18.1)
Cash flows used in investing activities: |  |  |
Capital expenditures | (55.2) | (50.9) | (75.4)
Premium payments on interest rate cap agreements |  | (2.4) | (0.5)
Acquisition of business, net of cash acquired |  |  | 0.0
Net cash used in investing activities | (55.2) | (53.3) | (75.9)
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 1,501.5 | 329.6 | 314.5
Repayments of borrowings under revolving credit facility | (1,501.5) | (329.6) | (314.5)
Repayments of long-term debt | (14.9) | (15.2) | (15.4)
Proceeds from issuance of long-term debt | 2,083.0 | 1,483.0 | 525.0
Payments to extinguish long-term debt | (2,121.3) | (1,490.4) | (525.3)
Net change in other long-term obligation | 0.0 | 0.0 |
Payment of debt financing costs | (9.6) | (4.5) | (6.8)
Net change in accounts payable-inventory financing | (0.2) | 1.5 | 0.0
Effective portion of interest rate cap agreements | 0.4 |  |
Proceeds from stock option exercises | 13.0 | 7.4 | 2.4
Proceeds from Coworker Stock Purchase Plan | 10.3 | 9.3 | 8.7
Repurchases of common stock | 0.0 | 0.0 | 0.0
Payment of incentive compensation plan withholding taxes | 0.0 |  | (0.6)
Dividends | 0.0 | 0.0 | 0.0
Principal payments under capital lease obligations | 0.0 | 0.0 |
Repayment of intercompany loan | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | 56.6 | 398.3 | (196.5)
Net cash (used in) provided by financing activities | 17.3 | 389.4 | (207.3)
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 | 0.0
Net (decrease) increase in cash and cash equivalents | (109.0) | 177.6 | (301.3)
Cash and cash equivalents – beginning of period | 222.7 | 45.1 | 346.4
Cash and cash equivalents – end of period | 113.7 | 222.7 | 45.1
Reportable Legal Entities | Guarantor Subsidiaries |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | 788.5 | 695.5 | 350.0
Cash flows used in investing activities: |  |  |
Capital expenditures | (6.3) | (7.6) | (11.6)
Premium payments on interest rate cap agreements |  | 0.0 | 0.0
Acquisition of business, net of cash acquired |  |  | 0.0
Net cash used in investing activities | (6.3) | (7.6) | (11.6)
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of long-term debt | 0.0 | 0.0 | 0.0
Proceeds from issuance of long-term debt | 0.0 | 0.0 | 0.0
Payments to extinguish long-term debt | 0.0 | 0.0 | 0.0
Net change in other long-term obligation | (3.8) | 15.7 |
Payment of debt financing costs | 0.0 | 0.0 | 0.0
Net change in accounts payable-inventory financing | (78.4) | 131.0 | 96.1
Effective portion of interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 0.0 | 0.0
Proceeds from Coworker Stock Purchase Plan | 0.0 | 0.0 | 0.0
Repurchases of common stock | 0.0 | 0.0 | 0.0
Payment of incentive compensation plan withholding taxes | 0.0 |  | 0.0
Dividends | 0.0 | 0.0 | 0.0
Principal payments under capital lease obligations | (0.2) | 1.0 |
Repayment of intercompany loan | 34.3 | 40.4 |
Distributions and advances from (to) affiliates | (737.2) | (872.9) | (434.5)
Net cash (used in) provided by financing activities | (785.3) | (684.8) | (338.4)
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 | 0.0
Net (decrease) increase in cash and cash equivalents | (3.1) | 3.1 | 0.0
Cash and cash equivalents – beginning of period | 3.1 | 0.0 | 0.0
Cash and cash equivalents – end of period | 0.0 | 3.1 | 0.0
Reportable Legal Entities | Non-Guarantor Subsidiaries |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | 52.3 | 56.1 | 27.9
Cash flows used in investing activities: |  |  |
Capital expenditures | (19.6) | (5.0) | (3.1)
Premium payments on interest rate cap agreements |  | 0.0 | 0.0
Acquisition of business, net of cash acquired |  |  | (263.8)
Net cash used in investing activities | (19.6) | (5.0) | (266.9)
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 59.2 | 9.2 | 0.0
Repayments of borrowings under revolving credit facility | (59.2) | (9.2) | 0.0
Repayments of long-term debt | 0.0 | (5.4) | (17.4)
Proceeds from issuance of long-term debt | 0.0 | 0.0 | 0.0
Payments to extinguish long-term debt | 0.0 | 0.0 | 0.0
Net change in other long-term obligation | 0.0 | 0.0 |
Payment of debt financing costs | 0.0 | (1.4) | 0.0
Net change in accounts payable-inventory financing | (5.4) | 11.1 | (0.2)
Effective portion of interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 0.0 | 0.0
Proceeds from Coworker Stock Purchase Plan | 0.0 | 0.0 | 0.0
Repurchases of common stock | 0.0 | 0.0 | 0.0
Payment of incentive compensation plan withholding taxes | 0.0 |  | 0.0
Dividends | 0.0 | 0.0 | 0.0
Principal payments under capital lease obligations | (1.1) | (1.6) |
Repayment of intercompany loan | (34.3) | (40.4) |
Distributions and advances from (to) affiliates | 0.0 | 0.0 | 267.4
Net cash (used in) provided by financing activities | (40.8) | (37.7) | 249.8
Effect of exchange rate changes on cash and cash equivalents | 2.6 | (7.4) | (3.5)
Net (decrease) increase in cash and cash equivalents | (5.5) | 6.0 | 7.3
Cash and cash equivalents – beginning of period | 37.9 | 31.9 | 24.6
Cash and cash equivalents – end of period | 32.4 | 37.9 | 31.9
Reportable Legal Entities | Co-Issuer |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | 0.0 | 0.0 | 0.0
Cash flows used in investing activities: |  |  |
Capital expenditures | 0.0 | 0.0 | 0.0
Premium payments on interest rate cap agreements |  | 0.0 | 0.0
Acquisition of business, net of cash acquired |  |  | 0.0
Net cash used in investing activities | 0.0 | 0.0 | 0.0
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of long-term debt | 0.0 | 0.0 | 0.0
Proceeds from issuance of long-term debt | 0.0 | 0.0 | 0.0
Payments to extinguish long-term debt | 0.0 | 0.0 | 0.0
Net change in other long-term obligation | 0.0 | 0.0 |
Payment of debt financing costs | 0.0 | 0.0 | 0.0
Net change in accounts payable-inventory financing | 0.0 | 0.0 | 0.0
Effective portion of interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 0.0 | 0.0
Proceeds from Coworker Stock Purchase Plan | 0.0 | 0.0 | 0.0
Repurchases of common stock | 0.0 | 0.0 | 0.0
Payment of incentive compensation plan withholding taxes | 0.0 |  | 0.0
Dividends | 0.0 | 0.0 | 0.0
Principal payments under capital lease obligations | 0.0 | 0.0 |
Repayment of intercompany loan | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | 0.0 | 0.0 | 0.0
Net cash (used in) provided by financing activities | 0.0 | 0.0 | 0.0
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 | 0.0
Net (decrease) increase in cash and cash equivalents | 0.0 | 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
Consolidating Adjustments |  |  |
Supplemental Guarantor Information [Line Items] |  |  |
Net cash provided by (used in) operating activities | 7.4 | 10.9 | (82.8)
Cash flows used in investing activities: |  |  |
Capital expenditures | 0.0 | 0.0 | 0.0
Premium payments on interest rate cap agreements |  | 0.0 | 0.0
Acquisition of business, net of cash acquired |  |  | 0.0
Net cash used in investing activities | 0.0 | 0.0 | 0.0
Cash flows used in financing activities: |  |  |
Proceeds from borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of borrowings under revolving credit facility | 0.0 | 0.0 | 0.0
Repayments of long-term debt | 0.0 | 0.0 | 0.0
Proceeds from issuance of long-term debt | 0.0 | 0.0 | 0.0
Payments to extinguish long-term debt | 0.0 | 0.0 | 0.0
Net change in other long-term obligation | 0.0 | 0.0 |
Payment of debt financing costs | 0.0 | 0.0 | 0.0
Net change in accounts payable-inventory financing | 0.0 | 0.0 | 0.0
Effective portion of interest rate cap agreements | 0.0 |  |
Proceeds from stock option exercises | 0.0 | 0.0 | 0.0
Proceeds from Coworker Stock Purchase Plan | 0.0 | 0.0 | 0.0
Repurchases of common stock | 0.0 | 0.0 | 0.0
Payment of incentive compensation plan withholding taxes | 0.0 |  | 0.0
Dividends | 0.0 | 0.0 | 0.0
Principal payments under capital lease obligations | 0.0 | 0.0 |
Repayment of intercompany loan | 0.0 | 0.0 |
Distributions and advances from (to) affiliates | (9.3) | 28.5 | 69.9
Net cash (used in) provided by financing activities | (9.3) | 28.5 | 69.9
Effect of exchange rate changes on cash and cash equivalents | 0.0 | 0.0 | 0.0
Net (decrease) increase in cash and cash equivalents | (1.9) | 39.4 | (12.9)
Cash and cash equivalents – beginning of period | 0.0 | (39.4) | (26.5)
Cash and cash equivalents – end of period | $ (1.9) | $ 0.0 | $ (39.4)

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- Definition The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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- Definition The cash inflow from a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 27 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3581-108585 + Details
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- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 + Details
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- Definition Amount of cash inflow from issuance of shares under share-based compensation arrangement, excluding stock option exercises. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 + Details
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- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Amount of cash inflow (outflow) from other long-term debt. + References No definition available. + Details
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901 + Details
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- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt and payment of capital lease obligations. + References No definition available. + Details
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- Definition Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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