XML 81 R66.htm IDEA: XBRL DOCUMENT v3.3.1.900
Pension and Postretirement Health and Life Benefits (Schedule of Net Benefit Costs) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Dec. 31, 2014
Jun. 30, 2015
Sep. 30, 2014
Dec. 31, 2015
Actuarial (gain) loss from remeasurement, net       $ (29.6)
Net periodic benefit cost (credit)       (26.4)
Successor [Member]        
Actuarial (gain) loss from remeasurement, net $ 10.4     (29.6)
Curtailment (gain) 0.0     0.0
Predecessor [Member]        
Actuarial (gain) loss from remeasurement, net     $ 0.0  
Curtailment (gain)     2.2  
Pension Plan, Defined Benefit [Member]        
Service costs 2.0   1.8 5.8
Interest costs 10.2   31.7 36.9
Expected return on plan assets (gains) (13.1)   (38.5) (47.4)
Amortization of actuarial (gains) losses, net 6.4   1.0 0.2
Actuarial (gain) loss from remeasurement, net (18.7) $ (3.9) (96.0) 55.2
Curtailment (gain)     (2.2)  
Net periodic benefit cost (credit) (5.5)   6.2 4.5
Postretirement Health and Life Benefits Plans [Member]        
Service costs 0.2   1.3 0.2
Interest costs 2.3   7.5 8.8
Expected return on plan assets (gains) (0.4)   (1.5) (0.8)
Amortization of actuarial (gains) losses, net 4.0     (29.8)
Actuarial (gain) loss from remeasurement, net (4.3)   (8.3) 30.2
Amortization of prior service costs (credits), net     0.3 0.3
Net periodic benefit cost (credit) $ (6.1)   $ (7.0) $ (21.9)