No definition available.

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

- Definition

Represents the number of lawsuits filed.

+ References

No definition available.

+ Details

Name:	hdy_LossContingencyNumberOfLawsuitsFiled
Namespace Prefix:	hdy_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

Name:	us-gaap_LegalFees
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of loss contingency liability.

+ References

+ Details

Name:	us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

+ Details

Name:	us-gaap_LossContingencyDamagesSoughtValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

+ Details

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

- Details

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

- Details

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

- Details

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

COMMITMENTS AND CONTINGENCIES (Details) $ in Millions			12 Months Ended		24 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) $ in Millions	Mar. 13, 2014 lawsuit	May. 09, 2012 USD ($) plaintiff	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)
Shareholder Lawsuits
LITIGATION AND OTHER LEGAL MATTERS
Provision for possible loss			$ 0.0		$ 0.0
Number of lawsuits filed \| lawsuit	2
Iroquois Lawsuit
LITIGATION AND OTHER LEGAL MATTERS
Provision for possible loss			0.0		0.0
Number of plaintiffs which filed lawsuit \| plaintiff		5
Damages sought		$ 18.5
Maximum possible loss		$ 18.5
Foreign Corrupt Practices Act Investigations
LITIGATION AND OTHER LEGAL MATTERS
Loss contingency amounts related to potential fines, sanctions or other penalties			0.0		0.0
Legal and other professional fees			$ 5.2	$ 7.5	$ 12.7