Income Taxes (Summary Of Income Tax Expense (Recovery)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Abstract]
Canadian, Current tax expense	$ 27,623	$ 21,712	$ 21,824
Canadian, Deferred tax expense	1,880	1,680	324
Current tax expense before application of operating loss carryforwards	16,707	12,236	15,712
Tax benefit of operating loss carryforwards	(1,910)	(627)	(627)
Total foreign current tax expense	14,797	11,609	15,085
Deferred tax expense before adjustment to opening valuation allowance	(273)	1,474	3,077
Adjustment to opening valuation allowance	(6,166)
Total foreign deferred tax expense	(6,439)	1,474	3,077
Income tax expense	$ 37,861	$ 36,475	$ 40,310