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Investments - Debt Securities, Trading (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Trading
Cost	$ 25.9	$ 24.6
Unrealized gains	0.8	0.0
Unrealized losses	0.0	(0.3)
Fair value	$ 26.7	$ 24.3

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Debt Securities, Trading, Accumulated Gross Unrealized Gain Before Tax

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amortized cost of investments in debt securities classified as trading.

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