Annual report pursuant to Section 13 and 15(d)

Pension And Other Postretirement Benefit Programs - Amounts Recognized on the Consolidated Balance Sheets (Details)

v3.20.1
Pension And Other Postretirement Benefit Programs - Amounts Recognized on the Consolidated Balance Sheets (Details) - USD ($)
$ in Millions
Dec. 31, 2019
Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]    
Pension benefit liabilities $ (16.0) $ (11.3)
Postretirement benefit liabilities (59.7) (55.7)
Retiree Health and Life Insurance Plans    
Defined Benefit Plan Disclosure [Line Items]    
Accounts payable and accrued expenses (5.6) (6.5)
Postretirement benefit liabilities (59.7) (55.7)
Net amount recognized (65.3) (62.2)
U.S. Pension Plan | Pension Plan    
Defined Benefit Plan Disclosure [Line Items]    
Pension benefit liabilities (13.9) (9.3)
Net amount recognized (13.9) (9.3)
Canadian Pension Plan | Pension Plan    
Defined Benefit Plan Disclosure [Line Items]    
Pension benefit liabilities (2.1) (2.0)
Net amount recognized $ (2.1) $ (2.0)