Components of Selected Balance Sheet Accounts (Detail) - USD ($) $ in Thousands		Dec. 31, 2018	Dec. 31, 2017
Other current assets:
Tubular inventory and well materials		$ 4,061	$ 5,146
Prepaid expenses		1,064	1,104
Other current assets		5,125	6,250
Other assets:
Deferred issuance costs of the Credit Facility		2,437	2,857
Escrow Deposit Remaining		0	3,210	[1]
Other		44	2,440
Accounts payable and accrued liabilities:
Trade accounts payable		16,507	22,579
Drilling costs		22,434	22,389
Royalties and revenue - related		51,212	39,287
Production, ad valorem and other taxes	[2]	2,418	1,275
Compensation-related		4,489	2,975
Interest		670	223
Bankruptcy Claims, amount reserved for outstanding claims		0	3,933
Other 2	[2]	5,970	3,520
Other liabilities:
Asset retirement obligations		4,314	3,286
Defined benefit pension obligations		857	971
Postretirement health care benefit obligations		362	476
Other		$ 0	$ 100

[1] 1 The December 31, 2017 amount represents amounts that had remained in the Escrow Account for the Devon Acquisition which fully funded the remaining liability due to Devon for the final settlement (see Note 5).

[2] 2 The amount for December 31, 2017 was reclassified from Accounts payable and accrued liabilities - Other.