Foreign Currency Risk (Details) CAD in Thousands, $ in Thousands	Dec. 31, 2015 USD ($)	Dec. 31, 2015 CAD	Dec. 31, 2014 USD ($)	Dec. 31, 2014 CAD	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)
Foreign Exchange Gain Loss [Line Items]
Cash and cash equivalents	$ 58,651		$ 72,026		$ 37,950	$ 60,162
Foreign Currency Exchange Risk [Member]
Foreign Exchange Gain Loss [Line Items]
Cash and cash equivalents	$ 17,836		$ 46,531
Cash and cash equivalents and marketable securities | CAD		CAD 56,491		CAD 43,516