Name:	hdy_AdditionalConsiderationGrossExpenditureCapAppraisalWell
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The gross expenditure cap related to future costs associated with the drilling of an exploration well to be paid on behalf of the entity as additional consideration in the sale of an investment.

No definition available.

Name:	hdy_AdditionalConsiderationGrossExpenditureCapWellExplorationDrilling
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The number of days after the rig contracted to drill an exploration well moves off the well location in which additional consideration in the sale of an investment is to be paid on behalf of the entity.

No definition available.

Name:	hdy_AdditionalConsiderationPaymentPeriod
Namespace Prefix:	hdy_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	hdy_OilAndGasPropertiesAndProjectsLineItems
Namespace Prefix:	hdy_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Represents the increase (decrease) in the property balance resulting from capitalized cost adjustment.

No definition available.

Name:	hdy_OilAndGasPropertiesBalanceIncreaseAmountAsResultOfCreditReceived
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The percentage interest in the investment of an oil and gas property.

No definition available.

Name:	hdy_OilAndGasPropertiesOwnershipInterest
Namespace Prefix:	hdy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the interest of the entity sold in the investment in oil and gas properties managed by the entity.

No definition available.

Name:	hdy_OilAndGasPropertiesOwnershipInterestSold
Namespace Prefix:	hdy_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations, inclusive of transaction cost.

No definition available.

Name:	hdy_ProceedsFromSaleOfOilAndGasPropertyAndEquipmentGross
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the threshold gross expenditure cap related to future costs associated with well to be paid by the entity in the sale of an investment.

No definition available.

Name:	hdy_ThresholdGrossExpenditureCapForDeterminationOfBearingPortionOfShareOfCost
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the transaction costs on sale of interest in unevaluated oil and gas property and equipment.

No definition available.

Name:	hdy_TransactionCostsOnSaleOfInterestInUnevaluatedOilAndGasPropertyAndEquipment
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10.(c)(7)(ii))
-URI http://asc.fasb.org/extlink&oid=50486907&loc=d3e511914-122862

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationCumulative
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_CapitalizedCostsOilAndGasProducingActivitiesNetAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=hdy_GuineaConcessionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_CounterpartyNameAxis=hdy_TullowGuineaLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	dei_LegalEntityAxis=hdy_DanaPetroleumEAndPLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: