Consolidated Statements Of Comprehensive Income (Parenthetical) (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Other comprehensive income/(loss), tax	$ 6.4	$ 27.9
Reclassifications to earnings of realized losses on available-for-sale securities	$ 0.0	(0.5)
Reclassifications to earnings of gains (loss) on cash flow hedging instruments		$ 0.3

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

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+ Details