Subsequent Events - Additional Information (Detail) - USD ($)		1 Months Ended	6 Months Ended
	Aug. 05, 2015	Jul. 31, 2015	Jun. 30, 2015	Jul. 29, 2015	Jul. 22, 2015	Jul. 08, 2015	Dec. 31, 2014	Jun. 30, 2014	May. 31, 2014
Subsequent Event [Line Items]
Dividends Payable			$ 0					$ 471,938
Shares outstanding			10,494,011				10,487,511
Great Plains [Member]
Subsequent Event [Line Items]
Financing Receivable, Gross									$ 3,100,000
Debt Instrument, Collateral Amount									$ 3,100,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend declared per share					$ 0.135
Dividends Payable				$ 1,417,164
Shares outstanding					10,497,511
Subsequent Event [Member] | PGC [Member]
Subsequent Event [Line Items]
Proceeds from Divestiture of Businesses	$ 1,900,000		$ 1,939,682
Subsequent Event [Member] | Energy West Wyoming [Member]
Subsequent Event [Line Items]
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates		$ 14,600,000
Subsequent Event [Member] | Shoshone and Glacier Pipeline [Member]
Subsequent Event [Line Items]
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates		$ 1,200,000
Subsequent Event [Member] | Great Plains [Member]
Subsequent Event [Line Items]
Debt Instrument, Collateral Amount						$ 3,100,000