Consolidated Statements of Income (Loss) and Comprehensive Income (Loss) (CAD)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue
Survey revenue [note 16]	3,913,367us-gaap_Revenues	2,684,095us-gaap_Revenues	10,937,575us-gaap_Revenues
Expense
Survey cost	431,518NSFDF_SurveyCost	1,632,159NSFDF_SurveyCost	3,633,645NSFDF_SurveyCost
General and administrative	4,132,108us-gaap_GeneralAndAdministrativeExpense	4,112,787us-gaap_GeneralAndAdministrativeExpense	4,508,506us-gaap_GeneralAndAdministrativeExpense
Stock based compensation expense [note 10]	658,000	492,000	265,000
Amortization of property and equipment	67,162	85,484	125,015
Total expense	5,288,788us-gaap_OperatingExpenses	6,322,430us-gaap_OperatingExpenses	8,532,166us-gaap_OperatingExpenses
Other expense (income)
Interest expense (income), net	(50,824)us-gaap_InterestIncomeExpenseNet	(25,455)us-gaap_InterestIncomeExpenseNet	2,744us-gaap_InterestIncomeExpenseNet
Foreign exchange loss (gain)	(158,817)	(150,350)	14,686
Increase (decrease) in fair value of US$ Warrants [note 12]	42,800NSFDF_OilAndNaturalGasOperations	1,371,500NSFDF_OilAndNaturalGasOperations	(168,143)NSFDF_OilAndNaturalGasOperations
Other expense	354,781us-gaap_OtherExpenses	107,985us-gaap_OtherExpenses	66,973us-gaap_OtherExpenses
Total other income (expense)	187,940us-gaap_NonoperatingIncomeExpense	1,303,680us-gaap_NonoperatingIncomeExpense	(83,740)us-gaap_NonoperatingIncomeExpense
Income (loss) before income taxes	(1,563,361)	(4,942,015)	2,489,149
Income tax expense [note 13]		399,546us-gaap_IncomeTaxExpenseBenefit	426,421us-gaap_IncomeTaxExpenseBenefit
Income (loss) and comprehensive income (loss)	(1,563,361)us-gaap_ComprehensiveIncomeNetOfTax	(5,341,561)us-gaap_ComprehensiveIncomeNetOfTax	2,062,728us-gaap_ComprehensiveIncomeNetOfTax
Income (loss) per share [note 9] - Basic	(0.04)us-gaap_EarningsPerShareBasic	(0.13)us-gaap_EarningsPerShareBasic	0.05us-gaap_EarningsPerShareBasic
Income (loss) per share [note 9] - Diluted	(0.04)us-gaap_EarningsPerShareDiluted	(0.13)us-gaap_EarningsPerShareDiluted	0.04us-gaap_EarningsPerShareDiluted

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