Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2016

Pension Costs

Defined Benefit Plan Disclosure [Line Items]

Schedule Of Benefit Plans

	Predecessor			Successor			Predecessor			Successor
	For the Three Months Ended June 30,						For the Six Months Ended June 30,
	2015			2016			2015			2016
	(Dollars in thousands)						(Dollars in thousands)
Service cost	$	506		$	508		$	1,333		$	1,016
Interest cost	1,526			1,498			3,052			2,996
Expected return on plan assets	(1,354		)	(1,310		)	(2,708		)	(2,620		)
Amortization of prior service cost	1			—			2			—
Net cost	$	679		$	696		$	1,679		$	1,392

Postretirement Costs

Defined Benefit Plan Disclosure [Line Items]

Schedule Of Benefit Plans

	Predecessor			Successor		Predecessor			Successor
	For the Three Months Ended June 30,					For the Six Months Ended June 30,
	2015			2016		2015			2016
	(Dollars in thousands)					(Dollars in thousands)
Service cost	$	4		$	1	$	8		$	2
Interest cost	315			272		630			543
Amortization of prior service cost	(43		)	—		(86		)	—
Net cost	$	276		$	273	$	552		$	545