Commitments and Contingencies - Additional Information (Detail) - USD ($) shares in Millions		1 Months Ended	12 Months Ended
	Mar. 11, 2015	Feb. 28, 2011	Dec. 31, 2016	Feb. 28, 2017	May 23, 2016	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 09, 2002	May 26, 1998
Gain Contingencies [Line Items]
Income derived from Cambridge RPC's			$ 12,986
Post finance cost proceeds										5.00%	5.00%
Required minimum market capitalization value					$ 35,000,000
Cash and cash equivalents			1,662,643				$ 2,241,317	$ 3,143,550	$ 21,322,257
Working capital deficit			24,500,000
Total assets			5,083,665				$ 6,913,016
Penelope Mining LLC [Member]
Gain Contingencies [Line Items]
Investment in convertible preferred stock	$ 101,000,000
Investment agreement period	3 years
MINOSA [Member]
Gain Contingencies [Line Items]
Amount of debt financed	$ 14,750,000
Bank loan amount			$ 14,750,000
Bank loan maturity date			Mar. 18, 2017
Monaco [Member] | Subsequent Event [Member]
Gain Contingencies [Line Items]
Amount of debt financed				$ 5,000,000
Line of credit				$ 750,000
Oceanica Resources S. de. R.L [Member]
Gain Contingencies [Line Items]
Grant and issuance of new equity shares						3.0
Maximum [Member] | Galt Resources [Member]
Gain Contingencies [Line Items]
Investment for future revenue rights		$ 7,512,500
Seattle and Cambridge Projects [Member]
Gain Contingencies [Line Items]
Deferred income from revenue participation rights			$ 887,500