Significant Accounting Policies - Equity Instruments and Investments (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Equity Instruments and Investments
Equity instruments with readily determinable fair value	$ 70.0	$ 142.2
Equity instruments without readily determinable fair values	259.8	217.2
Debt securities of our captive insurance companies	$ 50.3	$ 60.9
Debt Securities \| Securities in captive insurance subsidiary portfolio \| Maximum
Equity Instruments and Investments
Short-term investment maturity period	1 year
Investment maturity period	10 years

Represents the maturity periods of the investments held by the entity.

No definition available.

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- Definition

Represents the short-term investment maturity period.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

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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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