Accumulated Other Comprehensive Income (Loss) (Schedule of Reclassifications) (Details) - USD ($) $ in Thousands		3 Months Ended								9 Months Ended	12 Months Ended
	Oct. 01, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Oct. 01, 2016	Dec. 31, 2015	Dec. 31, 2014
Successor [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues		$ 575,688
Income (loss) before income taxes		34,605
Provision for (benefit from) income taxes		(1,156)
Net income (loss)		33,449
Successor [Member] | Reclassification out of accumulated other comprehensive income [Member] | Derivative Instruments [Member] | Commodity Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues		0
Provision for (benefit from) income taxes		0
Net income (loss)		0
Successor [Member] | Reclassification out of accumulated other comprehensive income [Member] | Pension, Postretirement and Other Post-Employment Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of prior service credits		0
Amortization of net actuarial gains (losses)		0
Income (loss) before income taxes		0
Provision for (benefit from) income taxes		0
Net income (loss)		0
Successor [Member] | Reclassification out of accumulated other comprehensive income [Member] | Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and investment income		0
Provision for (benefit from) income taxes		0
Net income (loss)		$ 0
Predecessor [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues			$ 550,305	$ 420,298	$ 428,106	$ 563,249	$ 688,544	$ 644,462	$ 677,005	$ 1,398,709	$ 2,573,260	$ 2,937,119
Income (loss) before income taxes										1,237,455	(3,286,522)	(532,719)
Provision for (benefit from) income taxes										4,626	373,380	(25,634)
Net income (loss)	$ 1,676,091		$ (51,421)	$ (175,887)	$ (206,702)	$ (632,368)	$ (1,999,476)	$ (168,103)	$ (113,195)	1,242,081	(2,913,142)	$ (558,353)
Predecessor [Member] | Reclassification out of accumulated other comprehensive income [Member] | Derivative Instruments [Member] | Commodity Contract [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues										397	9,575
Provision for (benefit from) income taxes										(81)	(3,447)
Net income (loss)										316	6,128
Predecessor [Member] | Reclassification out of accumulated other comprehensive income [Member] | Pension, Postretirement and Other Post-Employment Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of prior service credits										7,854	8,335
Amortization of net actuarial gains (losses)										(6,010)	(16,369)
Income (loss) before income taxes										1,844	(8,034)
Provision for (benefit from) income taxes										(481)	2,892
Net income (loss)										1,363	(5,142)
Predecessor [Member] | Reclassification out of accumulated other comprehensive income [Member] | Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and investment income										(2,263)	(6,391)
Provision for (benefit from) income taxes										1,038	2,308
Net income (loss)										$ (1,225)	$ (4,083)