Income Taxes - Net Operating Losses and Tax Rates (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net operating losses
Statutory Federal income tax rate (as a percent)	21.00%	21.00%	21.00%
Domestic Tax Authority [Member]
Net operating losses
Operating loss carryforward	$ 745.8	$ 987.0
Estimated effective tax rate on net operating losses		21.00%
State and Local Jurisdiction [Member]
Net operating losses
Operating loss carryforward	$ 554.7	$ 653.1
Estimated effective tax rate on net operating losses		3.45%