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Financial Instruments and Fair Value Measurements - Schedule of Long-term Debt Carrying Value and Fair Value (Details) - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018
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Carrying Value |  |
Debt Instrument [Line Items] |  |
Debt, fair value | $ 888.8 | $ 922.2
Carrying Value | 5.00% Senior Notes |  |
Debt Instrument [Line Items] |  |
Debt, fair value | 546.1 | 545.0
Carrying Value | 5.25% Senior Notes |  |
Debt Instrument [Line Items] |  |
Debt, fair value | 297.9 | 297.5
Carrying Value | Real estate related |  |
Debt Instrument [Line Items] |  |
Debt, fair value | 44.8 | 79.7
Fair Value |  |
Debt Instrument [Line Items] |  |
Debt, fair value | 912.9 | 884.3
Fair Value | 5.00% Senior Notes |  |
Debt Instrument [Line Items] |  |
Debt, fair value | 558.6 | 521.6
Fair Value | 5.25% Senior Notes |  |
Debt Instrument [Line Items] |  |
Debt, fair value | 309.1 | 286.5
Fair Value | Real estate related |  |
Debt Instrument [Line Items] |  |
Debt, fair value | $ 45.2 | $ 76.2

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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- Details
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- Details
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- Details
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