Debt (Details) - Falcon Credit Facility [Member] - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Aug. 23, 2018
Line Of Credit Facility [Line Items]
Borrowing base on credit facility	$ 500.0
Current borrowing base	70.0
Drawn under credit facility	$ 39.0	$ 38.0
Credit facility interest rate	2.64%
Available for future borrowings under the credit facility	$ 31.0
Description of maximum aggregate revolving borrowings	The Credit Facility provides for a maximum credit amount of $500.0 million and a borrowing base based on its oil and natural gas reserves and other factors is currently $70.0 million, subject to scheduled semi-annual and other borrowing base redeterminations and expires on the fifth anniversary of the Closing Date.
Expense incurred in closing of Credit Facility	$ 3.2
Unamortized deferred issuance costs	$ 2.0
Borrowings interest rate, description	Principal amounts borrowed are payable on the maturity date. The Company has a choice of borrowing at an alternative base rate (which is equal to the greatest of the federal funds rate plus one-half of 1.0%, the prime rate or the one-month LIBOR rate plus 1.0%) or LIBOR, with such borrowings bearing interest, payable quarterly in arrears for base rate loans and one month, two-month, three month or six-month periods for LIBOR loans. LIBOR loans bear interest at a rate per annum equal to the rate appearing on the Reuters Reference LIBOR01 or LIBOR02 page as the LIBOR, for deposits in dollars at 12:00 noon (London, England time) for one, two, three, or six months plus an applicable margin ranging from 200 to 300 basis points. Base rate loans bear interest at a rate per annum equal to the greatest of (i) the agent bank’s reference rate, (ii) the federal funds effective rate plus 50 basis points and (iii) the rate for one-month LIBOR loans plus 1%, plus an applicable margin ranging from 100 to 200 basis points. The scheduled redeterminations of our borrowing base take place on April 1st and October 1st of each year.
Federal Funds [Member]
Line Of Credit Facility [Line Items]
Applicable margin	0.50%
London Interbank Offered Rate (LIBOR)
Line Of Credit Facility [Line Items]
Applicable margin	1.00%
London Interbank Offered Rate (LIBOR) \| Minimum [Member]
Line Of Credit Facility [Line Items]
Applicable margin	1.00%
London Interbank Offered Rate (LIBOR) \| Maximum [Member]
Line Of Credit Facility [Line Items]
Applicable margin	2.00%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before accumulated amortization, of debt issuance costs related to line of credit arrangements. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The carrying value as of the balance sheet date of the current and noncurrent portions 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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- Definition

Description of the credit facility's borrowing capacity including discussion of how the borrowing capacity is determined (for example, borrowing capacity based on the amount of current assets).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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The effective interest rate during the reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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