Consolidated Statements Of Comprehensive Income (Parenthetical) (Unaudited) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Other comprehensive income/(loss), tax	$ (27,900,000)	$ 10,100,000
Reclassifications to earnings of realized losses on available-for-sale securities	(500,000)	0
Reclassifications to earnings of gains (loss) on cash flow hedging instruments	$ (300,000)	$ 1,500,000

Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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