Fresh Start Accounting - Application of Fresh Start Accounting to Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	May 04, 2017
Current assets:
Cash and cash equivalents	$ 0	$ 49,704	$ 6,392	$ 20,140
Restricted cash	325	325		7,411
Accounts receivable	33,145	29,514		33,560
Short-term derivative instruments	5,879	18,813		51,329
Prepaid expenses and other current assets	13,238	7,241		10,904
Total current assets	52,587	105,597		123,344
Property and equipment, net				657,336
Long-term derivative instruments	6,364	2,469		33,800
Restricted investments	4,622	94,467		156,443
Other long-term assets	5,837	6,129		10,504
Total assets	877,539	836,843		981,427
Current liabilities:
Accounts payable	8,310	2,345		2,890
Revenues payable	29,167	24,779		22,747
Accrued liabilities	23,358	23,155		38,180
Current portion of long-term debt				0
Total current liabilities	61,088	50,418		63,817
Liabilities subject to compromise				0
Long-term debt	285,000	294,000		430,000
Asset retirement obligations	90,466	75,867	99,460	95,186
Deferred tax liabilities	0	0		2,206
Other long-term liabilities	3,753	0		78
Total liabilities	443,332	420,285		591,287
Commitments and contingencies (see Note 18)				0
Stockholders' equity:
Predecessor common units				0
Successor warrants	4,790	4,788		4,788
Successor common stock	209	3		3
Additional paid-in capital	424,399	355,872		385,349
Total stockholders' equity	434,207	416,558	$ 393,933	390,140
Total liabilities and equity	$ 877,539	$ 836,843		981,427
Reorganization Adjustments [Member]
Current assets:
Cash and cash equivalents				(62,910)
Restricted cash				7,411
Accounts receivable				0
Short-term derivative instruments				0
Prepaid expenses and other current assets				675
Total current assets				(54,824)
Property and equipment, net				0
Long-term derivative instruments				0
Restricted investments				0
Other long-term assets				8,575
Total assets				(46,249)
Current liabilities:
Accounts payable				1,389
Revenues payable				0
Accrued liabilities				2,939
Current portion of long-term debt				(454,799)
Total current liabilities				(450,471)
Liabilities subject to compromise				(1,162,437)
Long-term debt				430,000
Asset retirement obligations				0
Deferred tax liabilities				0
Other long-term liabilities				0
Total liabilities				(1,182,908)
Commitments and contingencies (see Note 18)				0
Stockholders' equity:
Predecessor common units				(80,601)
Successor warrants				4,788
Successor common stock				3
Additional paid-in capital				1,212,469
Total stockholders'/ partners' equity				1,136,659
Total liabilities and equity				(46,249)
Fresh Start Adjustments [Member]
Current assets:
Cash and cash equivalents				0
Restricted cash				0
Accounts receivable				0
Short-term derivative instruments				0
Prepaid expenses and other current assets				0
Total current assets				0
Property and equipment, net				(894,164)
Long-term derivative instruments				0
Restricted investments				0
Other long-term assets				0
Total assets				(894,164)
Current liabilities:
Accounts payable				0
Revenues payable				0
Accrued liabilities				(1,713)
Current portion of long-term debt				0
Total current liabilities				(1,713)
Liabilities subject to compromise				0
Long-term debt				0
Asset retirement obligations				(62,928)
Deferred tax liabilities				0
Other long-term liabilities				(2,403)
Total liabilities				(67,044)
Commitments and contingencies (see Note 18)				0
Stockholders' equity:
Predecessor common units				0
Successor warrants				0
Successor common stock				0
Additional paid-in capital				(827,120)
Total stockholders'/ partners' equity				(827,120)
Total liabilities and equity				(894,164)
Predecessor [Member]
Current assets:
Cash and cash equivalents				27,701
Property and equipment, net				1,551,500
Current liabilities:
Asset retirement obligations				95,186
Predecessor [Member] | Balances Prior to Reorganization and Fresh Start Adjustments [Member]
Current assets:
Cash and cash equivalents				83,050
Restricted cash				0
Accounts receivable				33,560
Short-term derivative instruments				51,329
Prepaid expenses and other current assets				10,229
Total current assets				178,168
Property and equipment, net				1,551,500
Long-term derivative instruments				33,800
Restricted investments				156,443
Other long-term assets				1,929
Total assets				1,921,840
Current liabilities:
Accounts payable				1,501
Revenues payable				22,747
Accrued liabilities				36,954
Current portion of long-term debt				454,799
Total current liabilities				516,001
Liabilities subject to compromise				1,162,437
Long-term debt				0
Asset retirement obligations				158,114
Deferred tax liabilities				2,206
Other long-term liabilities				2,481
Total liabilities				1,841,239
Commitments and contingencies (see Note 18)				0
Stockholders' equity:
Predecessor common units				80,601
Successor warrants				0
Successor common stock				0
Additional paid-in capital				0
Total stockholders'/ partners' equity				80,601
Total liabilities and equity				1,921,840
Predecessor [Member] | Reorganization Adjustments [Member]
Current liabilities:
Liabilities subject to compromise				$ (1,162,437)