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Other Consolidated Financial Statement (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Class of Stock [Line Items]
Gain (loss) on investments, net	$ (436.6)	$ (77.3)
Other long-term liabilities	1,411.8		$ 1,329.6
Accrued income taxes	725.2		$ 709.9
Net gains recognized on the increase in fair value of equity securities	(442.3)	(60.9)
Proceeds from sale of available-for-sale securities, equity	91.2	$ 0.5
Ionis, Sangamo, Denali and Sage
Class of Stock [Line Items]
Net gains recognized on the increase in fair value of equity securities	$ 442.0

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