Segment Reporting (Schedule Of Financial Information Concerning Reportable Segments) (Details) $ in Thousands	5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2015 USD ($)	Aug. 14, 2015 USD ($)	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segment			2
Net sales			$ 437,963	$ 533,040	$ 825,145
Industrial Materials [Member]
Segment Reporting Information [Line Items]
Additions to lower of cost or market reserve			19,000
Other expense (income), net		$ 2,700			34,500
Preferred Stock Issuance Expense		3,200
Mark To Market Adjustment					3,500
Impairment of long-lived assets and goodwill		35,400			76,100
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Other expense (income), net					6,300
Preferred Stock Issuance Expense		19,400
Mark To Market Adjustment					(6,300)
Proxy Context Costs					2,400
Predecessor [Member]
Segment Reporting Information [Line Items]
Additions to lower of cost or market reserve		0			0
Net sales	$ 193,133	339,907			825,145
Total segment operating income (loss)	(12,563)	(68,249)			(119,974)
Other expense (income), net	(813)	1,421			2,920
Interest expense		26,211			35,736
Interest income	(6)	(363)			(320)
Loss before income taxes	(21,743)	(95,518)	116,421		(158,310)
Inventory write-downs		0			19,600
Restructuring Costs		4,422			40,350
Impairment of long-lived assets and goodwill		35,381			75,650
Predecessor [Member] | Industrial Materials [Member]
Segment Reporting Information [Line Items]
Net sales	193,133	339,907			825,145
Total segment operating income (loss)	(2,529)	(24,900)			(51,300)
Restructuring Costs		2,696			34,479
Predecessor [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Total segment operating income (loss)	(10,034)	(43,349)			(68,674)
Restructuring Costs		$ 1,726			$ 5,871
Successor [Member]
Segment Reporting Information [Line Items]
Additions to lower of cost or market reserve	0		18,974
Net sales	193,133		437,963
Total segment operating income (loss)	(12,563)		(92,053)
Other expense (income), net	(813)		(2,188)
Interest expense	9,999		26,914
Interest income	(6)		(358)
Loss before income taxes	(21,743)		(116,421)
Inventory write-downs	0		1,770
Restructuring Costs	389		2,365
Impairment of long-lived assets and goodwill	0		2,843
Successor [Member] | Industrial Materials [Member]
Segment Reporting Information [Line Items]
Net sales			437,963
Total segment operating income (loss)			(63,827)
Restructuring Costs	28		1,842
Successor [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Total segment operating income (loss)			(28,226)
Restructuring Costs	$ 361		$ 523