Severance and Retention Costs, Restructured North American TEGSEDI Operations (Details) - Restructured North American TEGSEDI Operations [Member] - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Sep. 30, 2021
Severance and Retention Costs [Abstract]
Beginning balance		$ 0.0
Amounts expensed during the period	$ 9.4	9.4
Amounts paid during the period		(9.2)
Ending balance		$ 0.2
Research, Development and Patent Expenses [Member]
Severance and Retention Costs [Abstract]
Amounts expensed during the period	2.3
Selling, General and Administrative Expenses [Member]
Severance and Retention Costs [Abstract]
Amounts expensed during the period	$ 7.1