Name:	nsfdf_LongTermDebtabstract
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

Name:	us-gaap_AccountsReceivableGross
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Date the debt agreement requires the first payment to be made, in YYYY-MM-DD format.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Subparagraph (SX 210.5-02.22)
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-Name Accounting Standards Codification
-Topic 942
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Name:	us-gaap_DebtInstrumentDateOfFirstRequiredPayment1
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The fair value of loans assumed in noncash investing or financing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Name Accounting Standards Codification
-Topic 230
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-Topic 230
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-URI http://asc.fasb.org/extlink&oid=123431023&loc=d3e4332-108586

Name:	us-gaap_LoansAssumed1
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Percentage increase in the stated interest rate on a short-term debt instrument.

No definition available.