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Other Consolidated Financial Statement (Details Textual) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Net gains recognized on the increase in fair value of equity securities	$ 153.9	$ 102.9	$ (288.4)	$ 42.0
Net gains (losses) realized during the period on equity securities	0.4	$ 0.0	6.6	$ 0.0
Other long-term liabilities	1,356.4		1,356.4		$ 1,329.6
Accrued income taxes	652.7		652.7		$ 709.9
Ionis, Sangamo, Denali and Sage
Net gains recognized on the increase in fair value of equity securities	263.0
Net losses recognized on the decrease in fair value of equity securities	$ 105.8		$ 284.8

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