Income Taxes - Gross Carryforwards (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Operating Loss Carryforwards [Line Items]
Increase (decrease) in valuation allowance	$ (56.6)
Expire Through Tax Year 2039
Operating Loss Carryforwards [Line Items]
Tax credit carryforwards	73.9
Net operating loss carryforwards	373.1
No Expiration
Operating Loss Carryforwards [Line Items]
U.S. interest carryforward	263.0
State tax credit carryforwards	4.1
U.S. Federal and Non-U.S. | No Expiration
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 1,273.3