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Financial Instruments and Fair Value Measurements - Schedule of Long-term Debt Carrying Value and Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Carrying Value
Debt Instrument [Line Items]
Debt, fair value	$ 634.3	$ 40.7
Carrying Value | 4.00% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Debt, fair value	550.0	0.0
Carrying Value | Real estate related
Debt Instrument [Line Items]
Debt, fair value	84.3	40.7
Fair Value
Debt Instrument [Line Items]
Debt, fair value	644.0	41.1
Fair Value | 4.00% Senior Notes | Senior Notes
Debt Instrument [Line Items]
Debt, fair value	567.0	0.0
Fair Value | Real estate related
Debt Instrument [Line Items]
Debt, fair value	$ 77.0	$ 41.1

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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.

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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.

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No definition available.

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