(4) Equity Investment in Sunrise Energy (Details) - Condensed Statement of Operations - Sunrise (Equity Investmentin SELLC [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Equity Investmentin SELLC [Member]
(4) Equity Investment in Sunrise Energy (Details) - Condensed Statement of Operations - Sunrise [Line Items]
Revenue	$ 782	$ 812
Expenses	(605)	(568)
Net income	$ 177	$ 244

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

No definition available.

Name:	hnrg_SELLCRevenues
Namespace Prefix:	hnrg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration