XML 102 R53.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Product Development Obligations - Additional Information (Detail) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 USD ($) DevelopmentObligation | Dec. 31, 2015 USD ($)
Debt Instrument [Line Items] |  |
Number of product development obligations | DevelopmentObligation | 11 |
Accrued product development costs excluding interest | $ 9.9 | $ 10.3
Accrued Interest | $ 4.9 | $ 4.8
Bank of Finland Interest Rate [Member] |  |
Debt Instrument [Line Items] |  |
Interest rate percentage | 1.00% |
Minimum [Member] |  |
Debt Instrument [Line Items] |  |
Interest rate on product development advances | 3.00% |

X
- Definition Accrued Product Development Costs Excluding Interest. + References No definition available. + Details
Name: | fgen_AccruedProductDevelopmentCostsExcludingInterest
Namespace Prefix: | fgen_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of product development obligations. + References No definition available. + Details
Name: | fgen_NumberOfProductDevelopmentObligations
Namespace Prefix: | fgen_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
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_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of interest payable on debt, including, but not limited to, trade payables. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
Name: | us-gaap_InterestPayableCurrentAndNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin. + References No definition available. + Details
Name: | us-gaap_LoansReceivableBasisSpreadOnVariableRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_VariableRateAxis=fgen_BankOfFinlandInterestRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |