XML 111 R58.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Equity and Stock-based Compensation - Subsidiary Stock and Non-Controlling Interests - Additional information (Detail) - $ / shares | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Nov. 19, 2014
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 0 | 0 |
IPO [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Conversion rights, shares issued upon conversion of each preferred share |  |  | 958,996
FibroGen Europe [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 42,619,022 | 42,619,022 |
Preferred stock redemption percentage | If a Preferred Share can be redeemed by a majority shareholder owning more than ninety percent (90%) of the shares of FibroGen Europe in accordance with the provisions of the Finnish Limited Liability Companies Act, the minority holders of Preferred Shares have the right to request redemption of their shares. |  |
Minimum percentage of shareholder's approval to call for redemption of preferred shares | 90.00% |  |
Preferred stock, voting rights | one vote |  |
Conversion rights, shares issued upon conversion of each preferred share | 1 |  |
FibroGen Europe [Member] | Series A [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 1,700,845 | 1,700,845 |
FibroGen Europe [Member] | Series B [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 1,875,000 | 1,875,000 |
FibroGen Europe [Member] | Series C [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 1,599,503 | 1,599,503 |
FibroGen Europe [Member] | Series D [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 1,520,141 | 1,520,141 |
FibroGen Europe [Member] | Series E [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 459,565 | 459,565 |
FibroGen Europe [Member] | Series F [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 5,714,332 | 5,714,332 |
FibroGen Europe [Member] | Series G [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 9,927,500 | 9,927,500 |
FibroGen Europe [Member] | Series H [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 19,822,136 | 19,822,136 |
FibroGen China [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Conversion rights, shares issued upon conversion of each preferred share | 1 |  |
FibroGen China [Member] | Series A [Member] |  |  |
Class Of Stock [Line Items] |  |  |
Preferred stock, shares outstanding | 6,758,000 | 6,758,000 |
Preferred shares issued, price per share | $ 1.00 |  |
Cash dividend percentage | 6.00% |  |

X
- Definition Preferred shares issued, price per share. + References No definition available. + Details
Name: | fgen_PreferredSharesIssuedPricePerShare
Namespace Prefix: | fgen_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Required minimum shareholder percentage to call for redemption of preferred shares. + References No definition available. + Details
Name: | fgen_RequiredMinimumShareholderPercentageToCallForRedemptionOfPreferredShares
Namespace Prefix: | fgen_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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_ClassOfStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares issued for each share of convertible preferred stock that is converted. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(27)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21506-112644 + Details
Name: | us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
Name: | us-gaap_PreferredStockDividendRatePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The redemption terms of preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity. The redemption features of this capital stock are solely within the control of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21564-112644 + Details
Name: | us-gaap_PreferredStockRedemptionTerms
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_PreferredStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Description of voting rights of nonredeemable preferred stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 + Details
Name: | us-gaap_PreferredStockVotingRights
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=us-gaap_IPOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=fgen_FibrogenEuropeOyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesAPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesBPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesCPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesDPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesEPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesFPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesGPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesHPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=fgen_FibroGenChinaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |