CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Paid-in Capital	Retained Earnings (Accumulated Deficit)	Deferred Compensation Obligation	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Predecessor [Member] Preferred Stock	Predecessor [Member] Common Stock	Predecessor [Member] Paid-in Capital	Predecessor [Member] Retained Earnings (Accumulated Deficit)	Predecessor [Member] Deferred Compensation Obligation	Predecessor [Member] Accumulated Other Comprehensive Income (Loss)	Predecessor [Member] Treasury Stock
Balance as of beginning of period (in shares) at Dec. 31, 2013			65,307,000
Balance as of beginning of period at Dec. 31, 2013	$ 788,804	$ 1,150	$ 466	$ 891,351	$ (104,180)	$ 2,792	$ 267	$ (3,042)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(409,592)				(409,592)
Dividends declared on preferred stock	0				(17,148)			0
Issuance of stock (in shares)			0
Issuance of common stock	313,330			310,080
Issuance of preferred stock		3,250
Conversion of preferred stock (in shares)			5,926,000
Conversion of preferred stock		(356)	$ 59	297	0
Induced conversion of preferred stock	(4,256)		$ 0	0
Share-based compensation (in shares)			15,000
Payments to induce conversion of preferred stock	3,627		$ 1	3,626
Deferred compensation (in shares)			0
Dividends declared on preferred stock ($600.00 and $348.33 per Series A and Series B preferred share, respectively)	(17,148)			0		(419)		303
Exercise of stock options (in shares)			257,000
Stock Issued During Period, Value, Stock Options Exercised	1,428		$ 3	1,425
Restricted stock unit vesting (in shares)			64,000
Deferred compensation	116		$ 0	(474)
Stock Issued During Period, Value, Restricted Stock Award, Gross	(474)
Exercise of stock options	(18)						(18)
Other	18			0
Balance as of end of period (in shares) at Dec. 31, 2014			71,569,000
Balance as of end of period at Dec. 31, 2014	675,817	4,044	$ 529	1,206,305	(535,176)	3,211	249	(3,345)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(1,582,961)				(1,582,961)
Dividends declared on preferred stock	(12,134)				12,134
Conversion of preferred stock (in shares)			9,414,000
Conversion of preferred stock	0	(898)	$ 94	804
Induced conversion of preferred stock	0				0
Share-based compensation (in shares)			195,000
Payments to induce conversion of preferred stock	4,540		$ 4	4,536
Deferred compensation (in shares)			2,000
Dividends declared on preferred stock ($600.00 and $348.33 per Series A and Series B preferred share, respectively)	0			0		(229)		229
Restricted stock unit vesting (in shares)			73,000
Deferred compensation	(556)		$ 1	(557)
Exercise of stock options	173						173
Balance as of end of period (in shares) at Dec. 31, 2015			81,253,000
Balance as of end of period at Dec. 31, 2015	(915,121)	3,146	$ 628	1,211,088	(2,130,271)	3,440	422	(3,574)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,054,602				1,054,602
Conversion of preferred stock (in shares)			6,965,000
Conversion of preferred stock	(38)
Induced conversion of preferred stock	0
Payments to induce conversion of preferred stock				1,511
Stock Issued During Period, Value, Stock Options Exercised	1,511
Deferred compensation	49,943
Exercise of stock options	(421)
Other		1,266	$ (69)	(1,198)			39
Balance as of end of period (in shares) at Sep. 12, 2016			88,218,000							0
Balance as of end of period at Sep. 12, 2016	0				0				$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Balance as of beginning of period (in shares) at Dec. 31, 2015			81,253,000
Balance as of beginning of period at Dec. 31, 2015	$ (915,121)	3,146	$ 628	1,211,088	(2,130,271)	3,440	422	(3,574)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)	0
Balance as of end of period (in shares) at Dec. 31, 2016			14,992,000
Balance as of end of period at Dec. 31, 2016	$ 185,548	0	$ 150	190,621	(5,296)	0	73	0
Issuance of Common Stock, Backstop Fee	9,059
Issuance of Common Stock, Exchange of Claims	$ 131,893
Postconfirmation, Shares outstanding	14,992,000
Postconfirmation, Stockholders' Equity	$ 190,895		150	190,745	0	0	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cancellation of Equity Upon Emergence from Bankruptcy	882,992	(1,880)	(697)	(1,213,797)	1,075,669	(3,440)	(383)	3,574
Cancellation of Total Equity Upon Emergence from Bankruptcy	(140,954)
Preconfirmation, Stockholders' Equity	140,954	1,880	$ 697	1,213,797	(1,075,669)	3,440	383	3,574
Cancellation of Equity Upon Emergence from Bankruptcy, Shares			(88,218,000)
Postconfirmation, Common Stock - Rights Offering			$ 76
Postconfirmation, Additional Paid-in Capital - Rights Offering			49,867
Postconfirmation, Common Stock - Backstop Fee			5
Postconfirmation, Additional paid-in capital - Backstop Fee			$ 9,054
Postconfirmation, Common Stock - Rights Offering, shares			7,634,000
Postconfirmation, Common Stock - Backstop Fee, Shares			473,000
Postconfirmation, Common Stock - Exchange of Claims,Shares			6,885,000
Postconfirmation, Common Stock - Exchange of Claims			$ 69
Postconfirmation, Additional paid-in capital - Exchange of Claims			$ 131,824
Balance as of beginning of period (in shares) at Sep. 12, 2016			88,218,000							0
Balance as of beginning of period at Sep. 12, 2016	0				0				$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(5,296)				(5,296)
Induced conversion of preferred stock	0
Payments to induce conversion of preferred stock				81
Exercise of stock options	73
Other	132			205	0	0	(73)	0
Balance as of end of period (in shares) at Dec. 31, 2016			14,992,000
Balance as of end of period at Dec. 31, 2016	$ 185,548	$ 0	$ 150	$ 190,621	$ (5,296)	$ 0	$ 73	$ 0