ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - General Overview (Details)	3 Months Ended
Sep. 30, 2016 subsidiary
ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES
Number of wholly-owned subsidiaries	2

Represents the wholly-owned subsidiaries of the entity.

No definition available.

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