Ur-Energy Inc. Quarterly report pursuant to Section 13 or 15(d)

Mineral Properties (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Mineral Properties, Rollforward
Balance, beginning of period	$ 52,750us-gaap_MineralPropertiesNet
Amortization	(1,295)us-gaap_AdjustmentForAmortization
Balance, end of period	51,455us-gaap_MineralPropertiesNet
Lost Creek Property [Member]
Mineral Properties, Rollforward
Balance, beginning of period	18,512
Amortization	(1,295)
Balance, end of period	17,217
Path Finder Mines [Member]
Mineral Properties, Rollforward
Balance, beginning of period		21,028
Balance, end of period	21,028	21,028
Other US Properties [Member]
Mineral Properties, Rollforward
Balance, beginning of period		13,210
Balance, end of period	$ 13,210	$ 13,210