Long-Term Debt	12 Months Ended
Dec. 31, 2019
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Credit Agreement On November 21, 2019, Earthstone, Earthstone Energy Holdings, LLC, a subsidiary of Earthstone (“EEH” or the “Borrower”), Wells Fargo Bank, National Association, as Administrative Agent and Issuing Bank (“Wells Fargo”), Royal Bank of Canada, as Syndication Agent, BOKF, NA dba Bank of Texas (“BOKF”) as Issuing Bank with respect to Existing Letters of Credit, SunTrust Bank, as Documentation Agent, and the lenders party thereto (the “Lenders”) entered into a credit agreement (the “Credit Agreement”). The Credit Agreement replaced the Prior Credit Agreement (as defined below), which was terminated on November 21, 2019. Concurrently with the effectiveness of the Credit Agreement, the Company terminated that certain credit agreement, dated as of May 9, 2017 (the “Prior Credit Agreement”), by and among the Borrower, Earthstone Operating, LLC, EF Non-Op, LLC, Sabine River Energy, LLC, Earthstone Legacy Properties, LLC, Lynden USA Operating, LLC, Bold Energy III LLC (“Bold”), Bold Operating, LLC the guarantors party thereto, the lenders party thereto, and BOKF, as administrative agent. In connection with the termination of the Prior Credit Agreement, $1.2 million of remaining unamortized deferred financing costs were expensed and included in Write-off of deferred financing costs in the Consolidated Statements of Operations. The initial borrowing base of the credit facility under the Credit Agreement is $325.0 million, and is subject to redetermination on or about November 1st and May 1st of each year. The amounts borrowed under the Credit Agreement bear annual interest rates at either (a) the adjusted LIBO Rate (as customarily defined) (the “Adjusted LIBO Rate”) plus 1.75% to 2.75% or (b) the sum of (i) the greatest of (A) the prime rate of Wells Fargo, (B) the federal funds rate plus ½ of 1.0%, and (C) the Adjusted LIBO Rate for an interest rate period of one month plus 1.0%, (ii) plus 0.75%to 1.75%, depending on the amount borrowed under the credit facility. Principal amounts outstanding under the credit facility are due and payable in full at maturity on November 21, 2024. All of the obligations under the Credit Agreement, and the guarantees of those obligations, are secured by substantially all of EEH’s assets. Additional payments due under the Credit Agreement include paying a commitment fee of 0.375% to 0.50% per year, depending on the amount borrowed under the credit facility, to the Lenders in respect of the unutilized commitments thereunder. EEH is also required to pay customary letter of credit fees. The Credit Agreement contains a number of covenants that, among other things, restrict, subject to certain exceptions, EEH’s ability to incur additional indebtedness, create liens on assets, make investments, pay dividends and distributions or repurchase its limited liability interests, engage in mergers or consolidations, sell certain assets, sell or discount any notes receivable or accounts receivable and engage in certain transactions with affiliates. In addition, the Credit Agreement requires EEH to maintain the following financial covenants: a current ratio of not less than 1.0 to 1.0 and for the four preceding quarters a consolidated leverage ratio of not greater than 4.0 to 1.0. Consolidated leverage ratio means the ratio of (i) the aggregate debt of EEH and its consolidated subsidiaries as at the last day of the fiscal quarter to (ii) EBITDAX for such fiscal quarter. The term “EBITDAX” means, for any period, the sum of consolidated net income for such period plus (a) the following expenses or charges to the extent deducted from consolidated net income in such period: (i) interest, (ii) taxes, (iii) depreciation, (iv) depletion, (v) amortization, (vi) certain distributions to employees related to the stock compensation, (vii) certain transaction related expenses, (viii) reimbursed indemnification expenses related to certain dispositions and investments, (ix) non-cash extraordinary, usual, or nonrecurring expenses or losses, (x) other non-cash charges and minus (b) to the extent included in consolidated net income in such period: (i) non-cash income and (ii) gains on asset dispositions, disposals and abandonments outside of the ordinary course of business. The Credit Agreement contains customary affirmative covenants and defines events of default to include failure to pay principal or interest, breach of covenants, breach of representations and warranties, insolvency, judgment default and a change in control. Upon the occurrence and continuance of an event of default, the Lenders have the right to accelerate repayment of the loans and exercise their remedies with respect to the collateral. At December 31, 2019, the Company was in compliance with all covenants under the Credit Agreement. As of December 31, 2019, the Company had a $325.0 million borrowing base under the Credit Agreement, of which $170.0 million was outstanding, bearing annual interest of 3.860%, resulting in an additional $155.0 million of borrowing base availability under the Credit Agreement. At December 31, 2018, there were $78.8 million of borrowings outstanding under the Prior Credit Agreement. For the year ended December 31, 2019, the Company had borrowings of $234.7 million and $143.5 million in repayments of borrowings. For the years ended December 31, 2019 and 2018, interest on all outstanding debt averaged 4.42% and 4.16% per annum, respectively, which excluded commitment fees of $0.7 million and $0.8 million for each period ended, respectively, and amortization of deferred financing costs of $0.4 million and $0.3 million for each period ended, respectively. The Company capitalized $1.6 million and $0.5 million, respectively, of costs associated with the credit agreements for the years ended December 31, 2019 and 2018. These capitalized costs are included in Other noncurrent assets in the Consolidated Balance Sheets. The Company’s policy is to capitalize the financing costs associated with its debt and amortize those costs on a straight-line basis over the term of the associated debt, which approximates the effective interest method over the term of the related debt.

Long-Term Debt

Credit Agreement

On November 21, 2019, Earthstone, Earthstone Energy Holdings, LLC, a subsidiary of Earthstone (“EEH” or the “Borrower”), Wells Fargo Bank, National Association, as Administrative Agent and Issuing Bank (“Wells Fargo”), Royal Bank of Canada, as Syndication Agent, BOKF, NA dba Bank of Texas (“BOKF”) as Issuing Bank with respect to Existing Letters of Credit, SunTrust Bank, as Documentation Agent, and the lenders party thereto (the “Lenders”) entered into a credit agreement (the “Credit Agreement”). The Credit Agreement replaced the Prior Credit Agreement (as defined below), which was terminated on November 21, 2019.

Concurrently with the effectiveness of the Credit Agreement, the Company terminated that certain credit agreement, dated as of May 9, 2017 (the “Prior Credit Agreement”), by and among the Borrower, Earthstone Operating, LLC, EF Non-Op, LLC, Sabine River Energy, LLC, Earthstone Legacy Properties, LLC, Lynden USA Operating, LLC, Bold Energy III LLC (“Bold”), Bold Operating, LLC the guarantors party thereto, the lenders party thereto, and BOKF, as administrative agent. In connection with the termination of the Prior Credit Agreement, $1.2 million of remaining unamortized deferred financing costs were expensed and included in Write-off of deferred financing costs in the Consolidated Statements of Operations.

The initial borrowing base of the credit facility under the Credit Agreement is $325.0 million, and is subject to redetermination on or about November 1st and May 1st of each year. The amounts borrowed under the Credit Agreement bear annual interest rates at either (a) the adjusted LIBO Rate (as customarily defined) (the “Adjusted LIBO Rate”) plus 1.75% to 2.75% or (b) the sum of (i) the greatest of (A) the prime rate of Wells Fargo, (B) the federal funds rate plus ½ of 1.0%, and (C) the Adjusted LIBO Rate for an interest rate period of one month plus 1.0%, (ii) plus 0.75%to 1.75%, depending on the amount borrowed under the credit facility. Principal amounts outstanding under the credit facility are due and payable in full at maturity on November 21, 2024. All of the obligations under the Credit Agreement, and the guarantees of those obligations, are secured by substantially all of EEH’s assets. Additional payments due under the Credit Agreement include paying a commitment fee of 0.375% to 0.50% per year, depending on the amount borrowed under the credit facility, to the Lenders in respect of the unutilized commitments thereunder. EEH is also required to pay customary letter of credit fees.

The Credit Agreement contains a number of covenants that, among other things, restrict, subject to certain exceptions, EEH’s ability to incur additional indebtedness, create liens on assets, make investments, pay dividends and distributions or repurchase its limited liability interests, engage in mergers or consolidations, sell certain assets, sell or discount any notes receivable or accounts receivable and engage in certain transactions with affiliates.

In addition, the Credit Agreement requires EEH to maintain the following financial covenants: a current ratio of not less than 1.0 to 1.0 and for the four preceding quarters a consolidated leverage ratio of not greater than 4.0 to 1.0. Consolidated leverage ratio means the ratio of (i) the aggregate debt of EEH and its consolidated subsidiaries as at the last day of the fiscal quarter to (ii) EBITDAX for such fiscal quarter. The term “EBITDAX” means, for any period, the sum of consolidated net income for such period plus (a) the following expenses or charges to the extent deducted from consolidated net income in such period: (i) interest, (ii) taxes, (iii) depreciation, (iv) depletion, (v) amortization, (vi) certain distributions to employees related to the stock compensation, (vii) certain transaction related expenses, (viii) reimbursed indemnification expenses related to certain dispositions and investments, (ix) non-cash extraordinary, usual, or nonrecurring expenses or losses, (x) other non-cash charges and minus (b) to the extent included in consolidated net income in such period: (i) non-cash income and (ii) gains on asset dispositions, disposals and abandonments outside of the ordinary course of business.

The Credit Agreement contains customary affirmative covenants and defines events of default to include failure to pay principal or interest, breach of covenants, breach of representations and warranties, insolvency, judgment default and a change in control. Upon the occurrence and continuance of an event of default, the Lenders have the right to accelerate repayment of the loans and exercise their remedies with respect to the collateral. At December 31, 2019, the Company was in compliance with all covenants under the Credit Agreement.

As of December 31, 2019, the Company had a $325.0 million borrowing base under the Credit Agreement, of which $170.0 million was outstanding, bearing annual interest of 3.860%, resulting in an additional $155.0 million of borrowing base availability under the Credit Agreement. At December 31, 2018, there were $78.8 million of borrowings outstanding under the Prior Credit Agreement.

For the year ended December 31, 2019, the Company had borrowings of $234.7 million and $143.5 million in repayments of borrowings.

For the years ended December 31, 2019 and 2018, interest on all outstanding debt averaged 4.42% and 4.16% per annum, respectively, which excluded commitment fees of $0.7 million and $0.8 million for each period ended, respectively, and amortization of deferred financing costs of $0.4 million and $0.3 million for each period ended, respectively.

The Company capitalized $1.6 million and $0.5 million, respectively, of costs associated with the credit agreements for the years ended December 31, 2019 and 2018. These capitalized costs are included in Other noncurrent assets in the Consolidated Balance Sheets. The Company’s policy is to capitalize the financing costs associated with its debt and amortize those costs on a straight-line basis over the term of the associated debt, which approximates the effective interest method over the term of the related debt.