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In the event of a default on the debt, the percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Amount of principal payments that were due during the period for the repayment short-term and long-term debt.

No definition available.

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Arrangement fee paid to the lender by the Company related to the Credit Agreement, recorded as a debt discount.

No definition available.

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Legal costs incurred related to the Credit Agreement, recorded as a debt discount.

No definition available.

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Represents a freestanding financial instrument that is not indexed to the Company's own shares.

No definition available.

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The percentage specified in the guarantee agreement with the Guarantor under which the party agrees to reimburse the Guarantor for any guaranty obligations paid to the lender, as a percent.

No definition available.

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Pertains to the warrants issued to the Guarantor And Co-Guarantor of the Credit Agreement.

No definition available.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	instant

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Data Type:	num:percentItemType
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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
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Data Type:	xbrli:durationItemType
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Amount, after accumulated amortization, of debt discount.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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Amount of the cost of borrowed funds accounted for as interest expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References

No definition available.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

No definition available.

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

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Data Type:	na
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Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
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Name:	us-gaap_ClassOfWarrantOrRightAxis=bhvn_WarrantsIssuedCommonIssuedCoGuarantorInConnectionWithCreditAgreementMember
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