Annual report pursuant to Section 13 and 15(d)

Postretirement Benefits Fair Values of Trust's Pension Assets (Details)

v3.22.0.1
Postretirement Benefits Fair Values of Trust's Pension Assets (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]      
Defined Contribution Plan Expense $ 47.1 $ 49.4 $ 44.1