Income Taxes - Net operating loss carryforwards and Tax Act (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Net operating loss carryforwards
Tax at statutory federal rate	21.00%	21.00%
Federal
Net operating loss carryforwards
Net operating loss carryforwards	$ 131.8
Net operating loss carryforwards, which will expire if not utilized	99.8
Net operating loss carryforwards, which will carryover indefinitely	32.0
State
Net operating loss carryforwards
Net operating loss carryforwards	50.2
Net operating loss carryforwards, which will expire if not utilized	48.5
Net operating loss carryforwards, which will carryover indefinitely	$ 1.7