XML 54 R38.htm IDEA: XBRL DOCUMENT
v3.19.1

Bank Debt (Amended Credit Facility Maximum Leverage Ratio) (Details) | Dec. 31, 2018
--- | ---
Line of Credit Facility [Line Items] |
Leverage Ratio | 255.00%
Maximum [Member] | September 30, 2018 through March 31, 2019 [Member] |
Line of Credit Facility [Line Items] |
Leverage Ratio | 375.00%
Maximum [Member] | June 30, 2019 and September 30, 2019 [Member] |
Line of Credit Facility [Line Items] |
Leverage Ratio | 350.00%
Maximum [Member] | December 31, 2019 through September 30, 2020 [Member] |
Line of Credit Facility [Line Items] |
Leverage Ratio | 325.00%
Maximum [Member] | December 31, 2020 through September 30, 2021 [Member] |
Line of Credit Facility [Line Items] |
Leverage Ratio | 300.00%
Maximum [Member] | December 31, 2021 and Each Fiscal Quarter Thereafter [Member] |
Line of Credit Facility [Line Items] |
Leverage Ratio | 275.00%

X
- Definition Leverage Ratio + References No definition available. + Details
Name: | hnrg_LeverageRatio
Namespace Prefix: | hnrg_
Data Type: | num:percentItemType
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_LineOfCreditFacilityLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodFiveMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |