LONG-TERM DEBT, NET (Long-Term Debt, Net) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total debt, net	$ 1,079,943,000	$ 864,123,000
Less: Liabilities subject to compromise	(855,943,000)	0
Less: Current portion	(224,000,000)	(690,123,000)
Long-term debt, net	0	174,000,000
KFM Credit Facility
Debt Instrument [Line Items]
Credit facility amount outstanding	224,000,000	174,000,000
7.875% Senior Unsecured Notes Due 2024
Debt Instrument [Line Items]
2024 Notes	500,000,000	500,000,000
Unamortized premium on 2024 notes	0	29,123,000
Less: Liabilities subject to compromise	(500,000,000)
7.875% Senior Unsecured Notes Due 2024 \| Alta Mesa RBL
Debt Instrument [Line Items]
2024 Notes	500,000,000.0
Alta Mesa RBL \| Alta Mesa RBL
Debt Instrument [Line Items]
Credit facility amount outstanding	355,943,000	$ 161,000,000
Less: Liabilities subject to compromise	$ (355,943,000)

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt premium.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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