8. Oil and Gas Properties (Tables)

12 Months Ended

Dec. 31, 2015

Oil and Gas Exploration and Production Industries Disclosures [Abstract]

Gross and net productive oil wells

	December 31, 2015				December 31, 2014
	Gross		Net		Gross		Net
North Dakota		344		10.58		242		7.51
Montana		5		0.37		5		0.37
		349		10.95		247		7.88

Capitalized costs for oil and gas properties

	Years Ended December 31,
	2015			2014
Purchases of oil and natural gas properties and development costs for cash	$	20,714,004		$	24,739,407
Purchase of oil and natural gas properties accrued at year-end		6,899,503			9,364,796
Purchase of oil and natural gas properties accrued at the beginning of the year		(9,364,796	)		(7,953,801	)
Advances to operators applied to development of oil and natural gas properties		–			6,036,748
Capitalized asset retirement obligations		48,711			103,778
Total purchase and development costs, oil and natural gas properties	$	18,297,422		$	32,290,928