Quarterly report pursuant to Section 13 or 15(d)

Reduction in Force (Details)

v2.4.1.9
Reduction in Force (Details) (USD $)
1 Months Ended 3 Months Ended
Mar. 31, 2015
employee
Mar. 31, 2015
Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]      
Restructuring reserve $ 1,055,132us-gaap_RestructuringReserve $ 1,055,132us-gaap_RestructuringReserve $ 449,351us-gaap_RestructuringReserve
Restructuring Costs Related to Equity Awards   372,000navb_RestructuringCostsRelatedtoEquityAwards  
Restructuring Reserve      
Number of employees terminated, staff 7navb_NumberofEmployeesTerminatedStaff    
Number of employees terminated, executives 4navb_NumberofEmployeesTerminatedExecutives    
Restructuring costs   1,400,000us-gaap_RestructuringCosts  
Separation payments, including payroll taxes      
Restructuring Cost and Reserve [Line Items]      
Restructuring reserve 964,013us-gaap_RestructuringReserve
/ us-gaap_RestructuringCostAndReserveAxis
= us-gaap_EmployeeSeveranceMember
964,013us-gaap_RestructuringReserve
/ us-gaap_RestructuringCostAndReserveAxis
= us-gaap_EmployeeSeveranceMember
 
Estimated cost of continuing healthcare coverage      
Restructuring Cost and Reserve [Line Items]      
Restructuring reserve $ 91,119us-gaap_RestructuringReserve
/ us-gaap_RestructuringCostAndReserveAxis
= navb_ContinuingHealthCareCoverageDomain
$ 91,119us-gaap_RestructuringReserve
/ us-gaap_RestructuringCostAndReserveAxis
= navb_ContinuingHealthCareCoverageDomain