Consolidated Statements Of Comprehensive Income (Parenthetical) (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Other comprehensive income/(loss), tax	$ 3.3	$ 8.7
Reclassifications to earnings of realized gains/(losses) on available-for-sale securities	$ 0.0	$ 5.6

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 7: 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