Pension and Postretirement Health and Life Benefits (Schedule of Net Benefit Costs) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Expected return on plan assets (gains)			$ (0.0675)
Successor [Member]
Actuarial (gain) loss from remeasurement, net			20,900,000
Curtailment (gain)	$ 0		0
Predecessor [Member]
Actuarial (gain) loss from remeasurement, net				$ 0
Curtailment (gain)		$ 2,200,000		2,200,000
Pension Plan, Defined Benefit [Member] | Successor [Member]
Service costs	1,100,000		3,100,000
Interest costs	9,200,000		27,800,000
Expected return on plan assets (gains)	(12,200,000)		(36,600,000)
Amortization of actuarial (gains) losses, net	0		0
Actuarial (gain) loss from remeasurement, net	24,800,000		20,900,000
Curtailment (gain)	0		0
Net periodic benefit cost (credit)	22,900,000		15,200,000
Pension Plan, Defined Benefit [Member] | Predecessor [Member]
Service costs		600,000		1,800,000
Interest costs		10,600,000		31,700,000
Expected return on plan assets (gains)		(12,900,000)		(38,500,000)
Amortization of actuarial (gains) losses, net		(400,000)		(1,000,000)
Actuarial (gain) loss from remeasurement, net		0		0
Curtailment (gain)		(2,200,000)		(2,200,000)
Net periodic benefit cost (credit)		(3,500,000)		(6,200,000)
Postretirement Health and Life Benefits Plans [Member] | Successor [Member]
Service costs	100,000		200,000
Interest costs	2,200,000		6,600,000
Expected return on plan assets (gains)	(200,000)		(700,000)
Amortization of prior service costs (credits), net	(100,000)		(200,000)
Net periodic benefit cost (credit)	$ 2,000,000		$ 5,900,000
Postretirement Health and Life Benefits Plans [Member] | Predecessor [Member]
Service costs		400,000		1,300,000
Interest costs		2,500,000		7,500,000
Expected return on plan assets (gains)		(500,000)		(1,500,000)
Amortization of prior service costs (credits), net		(100,000)		(300,000)
Net periodic benefit cost (credit)		$ 2,300,000		$ 7,000,000