Summary of Significant Accounting Policies - Summary of Accounts Receivable (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for doubtful accounts	$ (1)	$ (106)
Accounts receivable	54,440	72,943
Accrued Oil, Gas, and NGL Sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable gross	42,248	44,860
Due from Joint Interest Owners
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable gross	11,293	27,435
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable gross	$ 900	$ 754