Income Taxes - Operating Loss and Credit Carryforwards (Details) $ in Millions	Dec. 31, 2020 USD ($)
Internal Revenue Service (IRS)
Operating Loss Carryforwards [Line Items]
Net operating losses	$ 526.9
Tax credit carryforward, amount	6.4
Internal Revenue Service (IRS) | Drug Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward, amount	2.0
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Net operating losses	343.2
Tax credit carryforward, amount	4.2
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating losses	$ 290.7