Fair Value Disclosure [Line Items]

No definition available.

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- Definition

Transfers between Fair Value Hierarchies

+ References

No definition available.

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- Definition

Amount of unrealized gain (loss) on investment in debt and equity securities.

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- Definition

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

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- Definition

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

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- Definition

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

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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).

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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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Fair Value (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Fair Value (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Fair Value Disclosure [Line Items]
Transfers between Fair Value Hierarchies	$ 0.0		$ 0.0
Allowance for Credit Loss			0.1		$ 0.1
Debt Securities, Available-for-Sale, Realized Gain		$ 0.1		$ 0.5
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost			5.9
Debt and Equity Securities, Unrealized Gain (Loss)			0.2
Equity Securities, FV-NI			6.1
U.S. Treasury debt securities
Fair Value Disclosure [Line Items]
Allowance for Credit Loss			0.0
Corporate/Other debt securities
Fair Value Disclosure [Line Items]
Allowance for Credit Loss			$ 0.1		$ 0.1