Regulatory Matters, Commitments, Contingencies and Environmental (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Regulatory Matters, Commitments, Contingencies And Environmental Liabilities [Abstract]
Accrued Environmental Loss Contingencies, Noncurrent	$ 1,000
Estimated litigation liability		$ 18,000
Contingent Residual Support Agreement, Amount	2,000,000
Contingent Residual Support Agreement
Other Commitments [Line Items]
Senior Notes	$ 1,000,000