- Definition

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.

+ References

No definition available.

+ Details

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

- Definition

Represents the depth, below seabed which is required to be drilled, of an exploration well.

+ References

No definition available.

+ Details

Name:	hdy_ExplorationWellsRequiredToBeDrilledDepthBelowSeabed
Namespace Prefix:	hdy_
Data Type:	num:lengthItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of receivable if extension well is not drilled under oil and gas properties arrangement.

+ References

No definition available.

+ Details

Name:	hdy_OilAndGasPropertiesAmountReceivableIfExtensionWellNotDrilled
Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Estimated period for completion of exploration well project, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

Extension period for second exploration, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Represents the maximum period of time over which current available liquidity could be exhausted.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

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

- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_LitigationCaseAxis=hdy_SettlementAndReleaseAgreementWithTullowAndDanaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

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

- Details

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

ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - Status of Our Business - Oil and Gas Properties (Details)			12 Months Ended
	Aug. 19, 2016 USD ($) m	Aug. 15, 2016 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2012	Dec. 30, 2012	Dec. 27, 2012
Settlement and Release Agreement with Tullow and Dana \| Subsequent event
Status of our Business
Settlement amount		$ 686,570
Guinea concession
Status of our Business
Ownership interest (as a percent)			37.00%	37.00%	77.00%
Threshold gross expenditure cap for well to be paid by the entity			$ 100,000,000
Gross expenditure cap			$ 100,000,000
Maximum period of time over which current available liquidity could be exhausted			12 months
Guinea concession \| Subsequent event
Status of our Business
Ownership interest (as a percent)	100.00%
Extension period for second exploration (in years)	1 year
Depth below seabed required to be drilled of an exploration well (in meters) \| m	2,500
Amount receivable, if extension well not drilled	$ 46,000,000
Estimated time for completion of exploration well project (in days)	42 days
Guinea concession \| Tullow Guinea Ltd
Status of our Business
Ownership interest sold (as a percent)				40.00%		40.00%
Guinea concession \| Dana
Status of our Business
Ownership interest (as a percent)			23.00%
Guinea concession \| Tullow Guinea Ltd
Status of our Business
Ownership interest (as a percent)			40.00%	40.00%