Annual report pursuant to Section 13 and 15(d)

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- Document And Entity Information
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Accounting Policies
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Notes Details

Note 4 - Revenue From Contracts With Customers (Details Textual)

v3.20.1

Note 4 - Revenue From Contracts With Customers (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Cumulative Effect of New Accounting Principle in Period of Adoption				$ (700,000)
Contract with Customer, Payment Term, Minimum	15 days
Contract with Customer, Payment Term, Maximum	90 days
Contract with Customer, Transaction Price of Royalties Using Expected Value Method	$ 0
Revenue from Contract with Customer, Including Assessed Tax	38,000	$ 338,000
Contract with Customer, Asset, Impairment Loss	0	0
Capitalized Contract Cost, Net, Total	0
Contract with Customer, Asset, after Allowance for Credit Loss, Total	0	12,000
Long-term Contract with Customer [Member]
Contract with Customer, Performance Obligation Satisfied in Previous Period	0	0
Grant [Member]
Revenue Not from Contract with Customer	$ 611,000	$ 761,000
INDIA
Contract with Customer, Term of Contract	8 years
CHINA
Contract with Customer, Term of Contract	10 years
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption				$ (700,000)
Accounting Standards Update 2014-09 [Member] \| Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 700,000
Accounting Standards Update 2014-09 [Member] \| Retained Earnings [Member] \| Sayre Pharmaceuticals [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			100,000
Accounting Standards Update 2014-09 [Member] \| Retained Earnings [Member] \| Beijing Sinotau Medical Research Co., Ltd. [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 600,000

- Definition

Amount of impairment loss recognized for write-down of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

No definition available.

+ Details

Name:	navb_ContractWithCustomerAssetImpairmentLoss
Namespace Prefix:	navb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The maximum timing of payment in exchange for good or service transferred to customer when right is conditioned on something other than passage of time and on obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

No definition available.

+ Details

Name:	navb_ContractWithCustomerPaymentTermMaximum
Namespace Prefix:	navb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum timing of payment in exchange for good or service transferred to customer when right is conditioned on something other than passage of time and on obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

No definition available.

+ Details

Name:	navb_ContractWithCustomerPaymentTermMinimum
Namespace Prefix:	navb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The term of a contract with a customer.

+ References

No definition available.

+ Details

Name:	navb_ContractWithCustomerTermOfContract
Namespace Prefix:	navb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

As part of a contract with a customer, this item represents the transaction price for royalties using the expected value method of revenue recognition.

+ References

No definition available.

+ Details

Name:	navb_ContractWithCustomerTransactionPriceOfRoyaltiesUsingExpectedValueMethod
Namespace Prefix:	navb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

+ Details

Name:	us-gaap_CapitalizedContractCostNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130533-203044

+ Details

Name:	us-gaap_ContractWithCustomerAssetNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12A
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL108322424-203045

+ Details

Name:	us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

+ Details

Name:	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

+ Details

Name:	us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue that is not accounted for under Topic 606.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

Name:	us-gaap_RevenueNotFromContractWithCustomer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_ContractWithCustomerDurationAxis=us-gaap_LongTermContractWithCustomerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_GrantMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=country_IN
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=country_CN
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_RetainedEarningsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201409Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=navb_SayrePharmaceuticalsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MajorCustomersAxis=navb_BeijingSinotauMedicalResearchCoLtdMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: