Changes in non-cash working capital (Details) (CAD)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes In Non-Cash Working Capital Details
Accounts receivable	46,949us-gaap_AccountsReceivableNet	176,429us-gaap_AccountsReceivableNet	(350,077)us-gaap_AccountsReceivableNet
Work-in-progress	299,842us-gaap_InventoryWorkInProcess	676,621us-gaap_InventoryWorkInProcess	135,747us-gaap_InventoryWorkInProcess
Prepaid expenses and deposits	(180,188)	(17,807)	(97,544)
Accounts payable and accrued liabilities	(156,729)	(684,369)	275,799
Deferred revenue	(2,781,101)NSFDF_DeferredRevenue1	2,463,998NSFDF_DeferredRevenue1	(1,459,393)NSFDF_DeferredRevenue1
Change in non-cash working capital	(2,771,227)	2,614,872	(1,495,468)
Portion attributable to:
Operating activities	(2,771,227)	2,614,872	(1,495,468)
Financing activities
Investing activities
Change in non-cash working capital	(2,771,227)NSFDF_ChangesInNoncashWorkingCapital	2,614,872NSFDF_ChangesInNoncashWorkingCapital	(1,495,468)NSFDF_ChangesInNoncashWorkingCapital

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations.

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