It represents the period of monthly vesting of share-based compensation awards.

No definition available.

Name:	nbrv_ShareBasedCompensationArrangementByShareBasedPaymentAwardMonthlyVestingPeriod
Namespace Prefix:	nbrv_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Share-Based Payments - Inducement Awards Outside of the 2019 Inducement Plan (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 31, 2018	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Fair Value Assumptions
Expected volatility (as a percent)				77.30%
Expected term of options (in years)				5 years 6 months
Risk-free interest rate (as a percent)				1.00%
Inducement Awards Outside of the 2019 Inducement Plan
Share-Based Payments
Share-based compensation expense		$ 0.1	$ 0.1	$ 0.2	$ 0.2
Additional disclosures
Weighted-average remaining contractual life				7 years 1 month 6 days
Total unrecognized compensation related to unvested options		$ 0.5		$ 0.5
Recognition period				1 year 1 month 6 days
Inducement Awards Outside of the 2019 Inducement Plan \| Vesting period, year one
Share-Based Payments
Percentage that vests during the period	25.00%
Inducement Awards Outside of the 2019 Inducement Plan \| Vesting period, year two
Share-Based Payments
Percentage that vests during the period	75.00%
Monthly vesting period	36 months
Inducement Awards Outside of the 2019 Inducement Plan \| Non-statutory option
Share-Based Payments
Vesting period	4 years
Options exercise price (in dollars per share)	$ 35.30
Exercise period	10 years
Options weighted average grant date fair value (in dollars per share)				$ 2.05
Inducement Awards Outside of the 2019 Inducement Plan \| Non-statutory option \| Chief Executive Officer
Share-Based Payments
Options granted during the period	85,000
Inducement Awards Outside of the 2019 Inducement Plan \| Restricted Stock Units ("RSUs")
Share-Based Payments
Options weighted average grant date fair value (in dollars per share)				$ 3.53
Inducement Awards Outside of the 2019 Inducement Plan \| Restricted Stock Units ("RSUs") \| Chief Executive Officer
Share-Based Payments
Restricted stock granted during the period	15
Inducement Awards Outside of the 2019 Inducement Plan \| Restricted Stock Units ("RSUs") \| Upon receipt of FDA approval
Share-Based Payments
Percentage that vests during the period	50.00%
Inducement Awards Outside of the 2019 Inducement Plan \| Restricted Stock Units ("RSUs") \| First anniversary of FDA approval
Share-Based Payments
Percentage that vests during the period	50.00%