Subsequent event (Narrative) (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jun. 30, 2015 USD ($)	Nov. 30, 2013 USD ($) shares	Jun. 19, 2015 USD ($) shares	Jun. 19, 2015 COP shares	May. 31, 2015 shares	Apr. 22, 2015	Nov. 30, 2014 shares
Stock Issued During Period, Value, New Issues		$ 5,068
Common Stock, Shares, Issued | shares					60,633,701		60,296,365
Common Stock, Shares, Outstanding | shares		53,066,656			60,633,701		60,296,365
Subsequent Event [Member]
NovaCopper Common Share for Each Sunward Common Share Held						0.30%
Common Stock, Shares, Issued | shares					43,100,000
Exchange Ratio of NovaCopper Options for Sunward Option						0.30%
Loss Contingency, Estimate of Possible Loss | COP				COP 2,623,203,975
Subsequent Event [Member] | Minimum [Member]
Combined Companies Cash Position			$ 20,000
Subsequent Event [Member] | Approximations [Member]
Common Stock, Shares, Outstanding | shares			103,800,000	103,800,000
Business Combination, Consideration Transferred	$ 23,000
Loss Contingency, Estimate of Possible Loss			$ 1,050