Supplemental Condensed Consolidated Financial Information (Condensed Consolidating Statements of Cash Flows (Unaudited)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities	$ 30,304	$ 29,912
INVESTING ACTIVITIES:
Capital expenditures	(2,034)	(17,528)
Producing properties and other acquisitions	0	(210)
Proceeds from disposition of property and equipment	4,462	1,751
Net cash provided by (used in) investing activities	2,428	(15,987)
FINANCING ACTIVITIES:
Borrowings under line of credit	2,700	71,400
Payments under line of credit	(22,700)	(35,100)
Intercompany borrowings (advances), net		0
Net payments on finance leases	(1,067)	(1,026)
Employee taxes paid by withholding shares	0	(43)
Bank overdrafts	809	(8,733)
Net cash provided by (used in) financing activities	(20,258)	26,498
Net increase in cash and cash equivalents	12,474	40,423
Cash, restricted cash, and cash equivalents, beginning of period	12,145	571
Cash, restricted cash, and cash equivalents, end of period	$ 25,188	40,994
Consolidating Adjustments [Member]
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities		0
INVESTING ACTIVITIES:
Capital expenditures		0
Producing properties and other acquisitions		0
Proceeds from disposition of property and equipment		0
Net cash provided by (used in) investing activities		0
FINANCING ACTIVITIES:
Borrowings under line of credit		0
Payments under line of credit		0
Intercompany borrowings (advances), net		0
Net payments on finance leases		0
Employee taxes paid by withholding shares		0
Bank overdrafts		0
Net cash provided by (used in) financing activities		0
Net increase in cash and cash equivalents		0
Cash, restricted cash, and cash equivalents, beginning of period		0
Cash, restricted cash, and cash equivalents, end of period		0
Parent [Member]
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities		(66,578)
INVESTING ACTIVITIES:
Capital expenditures		(421)
Producing properties and other acquisitions		0
Proceeds from disposition of property and equipment		0
Net cash provided by (used in) investing activities		(421)
FINANCING ACTIVITIES:
Borrowings under line of credit		39,300
Payments under line of credit		(23,500)
Intercompany borrowings (advances), net		75,016
Net payments on finance leases		0
Employee taxes paid by withholding shares		(43)
Bank overdrafts		(7,269)
Net cash provided by (used in) financing activities		83,504
Net increase in cash and cash equivalents		16,505
Cash, restricted cash, and cash equivalents, beginning of period		503
Cash, restricted cash, and cash equivalents, end of period		17,008
Combined Guarantor Subsidiaries [Member]
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities		86,663
INVESTING ACTIVITIES:
Capital expenditures		(13,051)
Producing properties and other acquisitions		(210)
Proceeds from disposition of property and equipment		1,700
Net cash provided by (used in) investing activities		(11,561)
FINANCING ACTIVITIES:
Borrowings under line of credit		0
Payments under line of credit		0
Intercompany borrowings (advances), net		(75,089)
Net payments on finance leases		0
Employee taxes paid by withholding shares		0
Bank overdrafts		0
Net cash provided by (used in) financing activities		(75,089)
Net increase in cash and cash equivalents		13
Cash, restricted cash, and cash equivalents, beginning of period		68
Cash, restricted cash, and cash equivalents, end of period		81
Combined Non-Guarantor Subsidiaries [Member]
OPERATING ACTIVITIES:
Net cash provided by (used in) operating activities		9,827
INVESTING ACTIVITIES:
Capital expenditures		(4,056)
Producing properties and other acquisitions		0
Proceeds from disposition of property and equipment		51
Net cash provided by (used in) investing activities		(4,005)
FINANCING ACTIVITIES:
Borrowings under line of credit		32,100
Payments under line of credit		(11,600)
Intercompany borrowings (advances), net		73
Net payments on finance leases		(1,026)
Employee taxes paid by withholding shares		0
Bank overdrafts		(1,464)
Net cash provided by (used in) financing activities		18,083
Net increase in cash and cash equivalents		23,905
Cash, restricted cash, and cash equivalents, beginning of period		0
Cash, restricted cash, and cash equivalents, end of period		$ 23,905