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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS - Schedule of Long-term Debt Carrying Value and Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Carrying Value
Debt Instrument
Debt, fair value	$ 632.6	$ 634.3
Carrying Value | Real estate related
Debt Instrument
Debt, fair value	82.6	84.3
Fair Value
Debt Instrument
Debt, fair value	619.7	644.0
Fair Value | Real estate related
Debt Instrument
Debt, fair value	$ 74.2	77.0
Senior Notes | 4.00% Senior Notes
Debt Instrument
Interest rate (as a percentage)	4.00%
Senior Notes | Carrying Value | 4.00% Senior Notes
Debt Instrument
Debt, fair value	$ 550.0	550.0
Senior Notes | Fair Value | 4.00% Senior Notes
Debt Instrument
Debt, fair value	$ 545.6	$ 567.0

X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
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X

- 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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X

- 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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