XML 58 R44.htm IDEA: XBRL DOCUMENT v3.22.4
Summary of Significant Accounting Policies (Environmental and ARO) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Accounting Policies [Abstract]      
Asset Retirement Obligation $ 1.9 $ 2.0 $ 3.8
Accretion Expense, Including Asset Retirement Obligations 0.0 0.1  
Increase (Decrease) in Asset Retirement Obligations 0.0 (1.8) $ 2.5
Asset Retirement Obligation, Cash Paid to Settle $ (0.1) $ (0.1)