Income Taxes - Operating Loss Carryforwards (Details) $ in Millions	Dec. 31, 2021 USD ($)
Federal
Operating loss carryforwards
Net operating loss	$ 279.4
Tax credit carryforwards	8.1
Federal | Tax Years 2023 through 2039
Operating loss carryforwards
Net operating loss	150.6
Federal | No expiration
Operating loss carryforwards
Net operating loss	128.8
State
Operating loss carryforwards
Net operating loss	271.8
Tax credit carryforwards	2.4
State | Tax Years 2023 through 2039
Operating loss carryforwards
Net operating loss	$ 271.8