XML 83 R62.htm IDEA: XBRL DOCUMENT
v3.22.4

Leases - Additional Information (Detail) $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 01, 2021 USD ($) Option | Mar. 31, 2021 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Lessee Lease Description [Line Items] |  |  |  |  |
Finance lease right-of-use assets |  |  | $ 435 | $ 761 |
Finance lease liability |  |  | 173 |  |
Operating lease right-of-use assets |  |  | 79,893 | 91,112 |
Operating lease liability |  |  | 89,885 |  |
Cash payment related to lease |  |  | $ 15,497 | 10,022 | $ 951
Minimum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 1 year |  |
Maximum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 5 years |  |
Office Spaces |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, expiration period |  |  | 2025 |  |
Office Equipment [Member] | Minimum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 1 year |  |
Office Equipment [Member] | Maximum [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, operating lease, lease term |  |  | 5 years |  |
ASC 842 [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Finance lease right-of-use assets |  |  | $ 0 | 24,654 | 0
Operating lease right-of-use assets |  |  | $ 0 | $ 93,222 | $ 0
Shorenstein Properties LLC [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, finance lease, initial lease term |  |  | 15 years |  |
Lessee, finance lease, expiration period |  |  | 2023 |  |
Shorenstein Properties LLC [Member] | Lease Amendment [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Lessee, finance lease, option to extend the additional lease term | 5 years |  |  |  |
Lessee, finance lease, additional lease expiration period | 2028 |  |  |  |
Percentage increases on each anniversary of rent commencement date 2023 | 2.00% |  |  |  |
Lessee, finance lease, existence of option to extend | true |  |  |  |
Lessee, finance lease, option to extend | Under the terms of the Lease Amendment, the Company has two optional rights to each extend the lease for an additional five years. |  |  |  |
Optional rights to extend lease | Option | 2 |  |  |  |
Rent increase commencement year first option | 2023 |  |  |  |
Percentage increases on each anniversary of rent commencement date 2028 | 3.00% |  |  |  |
Rent increase commencement year second option | 2028 |  |  |  |
Shorenstein Properties LLC [Member] | Lease Amendment [Member] | ASC 842 [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Finance lease right-of-use assets | $ 24,600 |  |  |  |
Finance lease liability | 32,600 |  |  |  |
Operating lease right-of-use assets | 93,200 |  |  |  |
Operating lease liability | $ 101,200 |  |  |  |
Beijing Economic-Technological Development Area [Member] |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |
Operating lease right-of-use assets |  | $ 3,400 |  |  |
Operating lease liability |  | $ 3,400 |  |  |
Lessee, operating lease, lease term |  | 5 years |  |  |
Lessee, operating lease, expiration period |  | 2026 |  |  |

X
- Definition Lessee, finance lease, additional lease expiration period. + References No definition available. + Details
Name: | fgen_LesseeFinanceLeaseAdditionalLeaseExpirationPeriod
Namespace Prefix: | fgen_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Lessee, finance lease, expiration period. + References No definition available. + Details
Name: | fgen_LesseeFinanceLeaseExpirationPeriod
Namespace Prefix: | fgen_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Lessee, finance lease, option to extend the additional lease term. + References No definition available. + Details
Name: | fgen_LesseeFinanceLeaseOptionToExtendAdditionalLeaseTerm
Namespace Prefix: | fgen_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Lessee, operating lease, expiration period. + References No definition available. + Details
Name: | fgen_LesseeOperatingLeaseExpirationPeriod
Namespace Prefix: | fgen_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of optional rights to extend lease. + References No definition available. + Details
Name: | fgen_NumberOfOptionalRightsToExtendLease
Namespace Prefix: | fgen_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage increases on anniversary of rent commencement date option two. + References No definition available. + Details
Name: | fgen_PercentageIncreasesOnAnniversaryOfRentCommencementDateOptionTwo
Namespace Prefix: | fgen_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage increases on each anniversary of rent commencement date. + References No definition available. + Details
Name: | fgen_PercentageIncreasesOnEachAnniversaryOfRentCommencementDate
Namespace Prefix: | fgen_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Rent commencement year option one. + References No definition available. + Details
Name: | fgen_ScheduledRentCommencementYearOptionOne
Namespace Prefix: | fgen_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Scheduled rent commencement year option two. + References No definition available. + Details
Name: | fgen_ScheduledRentCommencementYearOptionTwo
Namespace Prefix: | fgen_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Present value of lessee's discounted obligation for lease payments from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918701-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
Name: | us-gaap_FinanceLeaseLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, after accumulated amortization, of right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
Name: | us-gaap_FinanceLeaseRightOfUseAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Indicates (true false) whether lessee has option to extend finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeFinanceLeaseExistenceOfOptionToExtend
Namespace Prefix: | us-gaap_
Data Type: | xbrli:booleanItemType
Balance Type: | na
Period Type: | duration

X
- Definition Description of terms and conditions of option to extend lessee's finance lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeFinanceLeaseOptionToExtend
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeFinanceLeaseTermOfContract1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LesseeLeaseDescriptionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseTermOfContract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI https://asc.fasb.org/extlink&oid=128292326&loc=SL77918686-209980 + Details
Name: | us-gaap_OperatingLeasePayments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=fgen_OfficeSpacesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_OfficeEquipmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201901Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=fgen_ShorensteinPropertiesLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LeaseContractualTermAxis=fgen_LeaseAmendmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=fgen_BeijingEconomicTechnologicalDevelopmentAreaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |