Fair Value of Financial Instruments (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)
Weighted Average
Fair Value [Line Items]
Interest rate (in percentage)	3.50%
Significant Unobservable Inputs (Level 3)
Fair Value [Line Items]
Notes payable, fair value	$ 85.6
Senior Notes \| Significant Unobservable Inputs (Level 3) \| Senior Notes Due 2027
Fair Value [Line Items]
Long-term debt, fair value	251.8
Senior Notes \| Significant Unobservable Inputs (Level 3) \| Senior Notes Due 2026
Fair Value [Line Items]
Long-term debt, fair value	199.2
Senior Notes \| Significant Other Observable Inputs (Level 2) \| Senior Notes Due 2024
Fair Value [Line Items]
Long-term debt, fair value	261.3
Senior Notes \| Significant Other Observable Inputs (Level 2) \| Senior Notes Due 2023
Fair Value [Line Items]
Long-term debt, fair value	$ 265.2

Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column B
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column B))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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+ References

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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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- Definition

Fair value portion of notes payable.

+ 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 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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