The number of shares issuable in connection with legal settlements.

No definition available.

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- Definition

The amount of cash payable for the settlement of litigation that would be covered under its directors and officers insurance policy.

+ References

No definition available.

+ Details

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- Definition

Maximum number of days for Security instrument to put in place from the date of the Presidential Decree.

+ References

No definition available.

+ Details

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- Definition

Information pertaining to Sufficient financing for Obligation Well cost as defined in Farmout Agreement " Cash and committed financing to the satisfaction of SAPETRO.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	hdy_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Represents the contract area of oil and gas properties, retained by the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	hdy_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Estimated total amount of drilling preparation cost to share of expenditures as per PSC oil and gas properties arrangement.

+ References

No definition available.

+ Details

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

- Definition

The amount of mutually acceptable security as per PSC oil and gas properties arrangement.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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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

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

- Definition

The period to correct delinquency in filing SEC Forms.

+ References

No definition available.

+ Details

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

- Definition

The number of shares issued during the period in connection with legal settlements.

+ References

No definition available.

+ Details

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Namespace Prefix:	hdy_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold amount to be paid according to new Farm-out agreement for additional 2% Participating interest assigned.

+ References

No definition available.

+ Details

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

- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

Name:	us-gaap_SubsequentEventLineItems
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SUBSEQUENT EVENTS (Details)									3 Months Ended	6 Months Ended
SUBSEQUENT EVENTS (Details)	Apr. 12, 2017 USD ($) km²	Mar. 30, 2017 USD ($)	Mar. 01, 2017 USD ($)	Feb. 27, 2017	Feb. 02, 2017 shares	Jan. 24, 2017 USD ($)	Jan. 11, 2017 USD ($)	Aug. 19, 2016 USD ($) km²	Dec. 31, 2016 USD ($) shares	Dec. 31, 2016 USD ($) plaintiff shares	Jun. 30, 2016	Dec. 31, 2012	Dec. 30, 2012	Mar. 25, 2010 mi²	Mar. 25, 2010 km²
Settlement of Iroquois Lawsuit
SUBSEQUENT EVENTS
Number of plaintiffs which filed lawsuit \| plaintiff										5
Number of shares will issue to the plaintiffs \| shares									600,000	600,000
Settlements in cash payable									$ 1,350,000	$ 1,350,000
Subsequent Event
SUBSEQUENT EVENTS
Period to correct delinquency				30 days
Subsequent Event \| Settlement of Iroquois Lawsuit
SUBSEQUENT EVENTS
Cash payment of settlements							$ 1,350,000
Number of shares issued to plaintiffs \| shares					600,000
Guinea concession
SUBSEQUENT EVENTS
Mutually acceptable security								$ 5,000,000	$ 5,000,000
Ownership interest (as a percent)								100.00%	100.00%	100.00%	37.00%	37.00%	77.00%
Contract area retained (in square kilometers/square miles)								5,000						9,650	25,000
Amount receivable, if extension well not drilled								$ 46,000,000
Guinea concession \| Subsequent Event
SUBSEQUENT EVENTS
Mutually acceptable security			$ 5,000,000			$ 5,000,000		$ 5,000,000
Ownership interest (as a percent)								100.00%
Contract area retained (in square kilometers/square miles) \| km²								5,000
Amount receivable, if extension well not drilled						$ 46,000,000		$ 46,000,000
Guinea concession \| Subsequent Event \| Farm-out Agreement
SUBSEQUENT EVENTS
Mutually acceptable security	$ 5,000,000
Contract area retained (in square kilometers/square miles) \| km²	5,000
Maximum days for security instrument to put in place	30 days
Guinea concession \| Subsequent Event \| SAPETERO \| Farm-out Agreement
SUBSEQUENT EVENTS
Ownership interest sold (as a percent)		50.00%
Ownership interest (as a percent)	2.00%
Sufficient financing for the Obligation Well Cost	$ 15,000,000
Threshold amount for additional assigned 2% participating interest	$ 1,000,000
Guinea concession \| Subsequent Event \| SAPETERO \| Farm-out Agreement \| Minimum
SUBSEQUENT EVENTS
Estimated total drilling preparation cost		$ 8,000,000
Guinea concession \| Subsequent Event \| SAPETERO \| Farm-out Agreement \| Maximum
SUBSEQUENT EVENTS
Estimated total drilling preparation cost		$ 10,000,000