Name:	fwbi_AgreementsLineItems
Namespace Prefix:	fwbi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Number of days allowed to cure from breaching of the agreement.

No definition available.

Name:	fwbi_ThresholdNumberOfDaysForBreachOfAgreementCurePeriodForTermination
Namespace Prefix:	fwbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Number of days allowed to cure from breaching of the agreement, if in case of a payment breach.

No definition available.

Name:	fwbi_ThresholdNumberOfDaysForBreachOfAgreementTerminationTermCurePeriodForPaymentBreach
Namespace Prefix:	fwbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Number of days prior written notice to be given for termination of the agreement.

No definition available.

Name:	fwbi_ThresholdNumberOfDaysToGivePriorWrittenNoticeInCaseOfTermination
Namespace Prefix:	fwbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 730
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483041/730-20-50-1

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

The amount of costs incurred under a research and development arrangement accounted for as a contract to perform research and development for others.

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersCostsIncurredGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 730
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482916/730-10-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 912
-SubTopic 730
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482517/912-730-25-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481283/985-20-50-1

Name:	us-gaap_ResearchAndDevelopmentExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Name:	us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=us-gaap_LicenseAgreementTermsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_CounterpartyNameAxis=fwbi_SanofiMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	fwbi_TypeOfMilestonePaymentAxis=fwbi_DevelopmentAndRegulatoryMilestonePaymentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: