Consolidated Statements of Comprehensive Income (Parenthetical) (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Other comprehensive income/(loss), tax (benefit) expense	$ 4.7	$ (3.3)
Reclassifications to earnings of realized gains/(losses) on available-for-sale securities	$ 0.0	$ 0.0

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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+ Details