Significant Accounting Policies - Additional Information (Details) - USD ($)		1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 21, 2018	Dec. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Significant Accounting Policies [Line Items]
Allowance for uncollectible accounts			$ 9,000,000
Discount rate future net revenues			10.00%
Ceiling test limitation			$ 0	$ 0
Inventory		$ 18,757,000	$ 18,277,000		$ 18,757,000
Common share, no par value
Contingently issuable shares			19,200,000	2,800,000
Maximum
Significant Accounting Policies [Line Items]
Lease term			1 year
Ultra Resources, Inc. | Exchange Agreement
Significant Accounting Policies [Line Items]
Warrants issued on exchange	10,919,499	10,919,499			10,919,499
Number of common stock issued upon exercise of each warrant	1	1			1
Initial exercise price	$ 0.01	$ 0.01			$ 0.01
Volume-weighted average price of the common shares for warrants exercise		$ 2.50			$ 2.50
Warrants Exercise description			No Warrants will be exercisable until the date on which the volume-weighted average price of the common shares is at least $2.50 per common share for 30 consecutive trading days (the “Trading Price Condition”).
Warrant expiration date		Jul. 14, 2025			Jul. 14, 2025
Pipe and Production Equipment
Significant Accounting Policies [Line Items]
Inventory			$ 17,200,000
Crude Oil Inventory
Significant Accounting Policies [Line Items]
Inventory			$ 1,100,000