Income Taxes - Operating Loss Carryforwards (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating Loss Carryforwards
Recognized valuation allowance relating to NOL carryforwards	$ 2,600.0
U.S. Federal
Operating Loss Carryforwards
Net operating loss carryforwards	418.3
U.S. Federal | Between 2030 and 2036
Operating Loss Carryforwards
Net operating loss carryforwards	3,700.0
State and Local Jurisdiction [Member]
Operating Loss Carryforwards
Net operating loss carryforwards	1,100.0
Foreign
Operating Loss Carryforwards
Net operating loss carryforwards	$ 10,900.0