XML 64 R51.htm IDEA: XBRL DOCUMENT
v3.21.2

Stock-Based Incentive Plan - Narrative (Details) |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 09, 2020 shares | Sep. 30, 2021 USD ($) well shares | Sep. 30, 2020 USD ($) shares | Jun. 30, 2021 shares | Dec. 08, 2016 shares
Stock-Based Incentive Plan |  |  |  |  |
Granted (in shares) |  | 196,940 | 0 |  |
Stock-based compensation expense | $ |  | $ 197,826 | $ 300,351 |  |
Restricted Stock, Time Vested |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Shares outstanding (in shares) |  | 342,341 |  |  |
Granted (in shares) |  | 65,647 |  |  |
Number of vesting tranches | well |  | 3 |  |  |
Restricted Stock, Performance-Based |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Shares outstanding (in shares) |  | 389,594 |  |  |
Granted (in shares) |  | 131,293 |  |  |
Performance Based Contingent Shares |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Shares outstanding (in shares) |  | 300,440 |  | 323,080 |
Company Performance Awards |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Shares outstanding (in shares) |  | 0 |  |  |
2016 Plan |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Number of shares of common stock authorized for issuance under plan (in shares) |  |  |  |  | 1,100,000
Number of additional shares authorized (in shares) | 2,500,000 |  |  |  |
Number of shares remaining available for grant under plan (in shares) |  | 2,009,354 |  |  |
Minimum | Restricted Stock, Time Vested |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Vesting period |  | 3 years |  |  |
Maximum | Restricted Stock, Time Vested |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Expiration period |  | 4 years |  |  |
Vesting period |  | 4 years |  |  |
Maximum | Restricted Stock, Performance-Based |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Expiration period |  | 4 years |  |  |
Maximum | Performance Based Contingent Shares |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Expiration period |  | 4 years |  |  |
Director |  |  |  |  |
Stock-Based Incentive Plan |  |  |  |  |
Vesting period |  | 1 year |  |  |

X
- Definition Share-based Compensation Arrangement by Share-based Payment Award, Number Of Vesting Tranches + References No definition available. + Details
Name: | epm_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberOfVestingTranches
Namespace Prefix: | epm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of additional shares authorized for issuance under share-based payment arrangement. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AwardTypeAxis=epm_RestrictedStockTimeVestedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=epm_RestrictedStockPerformanceBasedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=epm_PerformanceBasedContingentSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=epm_CompanyPerformanceAwardsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PlanNameAxis=epm_A2016EquityIncentivePlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_TitleOfIndividualAxis=srt_DirectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |