BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Supplemental Cash Items:
Cash Paid During the Period for Interest, Net of Amount Capitalized	$ 15,990	$ 16,929
Non-cash Investing Activities:
Oil and Natural Gas Properties Included in Accounts Payable and Accrued Liabilities	143,220	133,872
Capitalized Asset Retirement Obligations	259	226
Compensation Capitalized on Oil and Gas Properties	184	84
Non-cash Financing Activities:
Issuance of 8.50% Second Lien Notes due 2023 - PIK Interest	0	1,742
Issuance of Preferred Stock for 2L Notes Repurchase	81,212	0
Contingent Consideration Settlements	$ 0	2,887
8.50% Second Lien Notes due 2023
Non-cash Financing Activities:
Interest rate	8.50%
Second Lien Notes | 8.50% Second Lien Notes due 2023
Non-cash Financing Activities:
Issuance of 8.50% Second Lien Notes due 2023 - PIK Interest	$ 0	$ 1,738