Adjustments to additional paid in capital related to premium payments.

No definition available.

Name:	bbio_AdjustmentsToAdditionalPaidInCapitalRelatedToPremiumPayments
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt instrument additional increase available in loan facilities.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentAdditionalIncreaseAvailableInLoanFacilities
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument additional increase available in loan facilities no later than fourteen months.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentAdditionalIncreaseAvailableInLoanFacilitiesNoLaterThanFourteenMonths
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument additional increase available in loan facilities upon achievement of certain performance milestones.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentAdditionalIncreaseAvailableInLoanFacilitiesUponAchievementOfCertainPerformanceMilestones
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument additional increase available in loan facilities year three.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentAdditionalIncreaseAvailableInLoanFacilitiesYearThree
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument additional principal borrowing amount.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentAdditionalPrincipalBorrowingAmount
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument amended maturity extension date

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentAmendedMaturityExtensionDate
Namespace Prefix:	bbio_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument capped call transaction cap price per share.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentCappedCallTransactionCapPricePerShare
Namespace Prefix:	bbio_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt instrument, convertible, increase in conversion rate, number of common stock issuable.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentConvertibleIncreaseInConversionRateNumberOfCommonStockIssuable
Namespace Prefix:	bbio_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument convertible threshold business days.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentConvertibleThresholdBusinessDays
Namespace Prefix:	bbio_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument convertible threshold consecutive trading day period.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentConvertibleThresholdConsecutiveTradingDayPeriod
Namespace Prefix:	bbio_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, final payment charge percentage.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentFinalPaymentChargePercentage
Namespace Prefix:	bbio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument interest only extension date.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentInterestOnlyExtensionDate
Namespace Prefix:	bbio_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument interest only extension date one.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentInterestOnlyExtensionDateOne
Namespace Prefix:	bbio_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument maturity date extension.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentMaturityDateExtension
Namespace Prefix:	bbio_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument option to purchase additional notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument Option to Purchase Additional Notes Exercised.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentOptionToPurchaseAdditionalNotesExercised
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument, option to purchase additional notes remaining portion exercised.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentOptionToPurchaseAdditionalNotesRemainingPortionExercised
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt instrument percentage of prepayment fee.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentPercentageOfPrepaymentFee
Namespace Prefix:	bbio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument principal amount denomination for conversion into common stock.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentPrincipalAmountDenominationForConversionIntoCommonStock
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt instruments maturity year.

+ References

No definition available.

+ Details

Name:	bbio_DebtInstrumentsMaturityYear
Namespace Prefix:	bbio_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Direct offering expense.

+ References

No definition available.

+ Details

Name:	bbio_DirectOfferingExpense
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Gain loss on debt modification.

+ References

No definition available.

+ Details

Name:	bbio_GainLossOnDebtModification
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Minimum threshold percentage of aggregate principal by trustee or holders.

+ References

No definition available.

+ Details

Name:	bbio_MinimumThresholdPercentageOfAggregatePrincipalByTrusteeOrHolders
Namespace Prefix:	bbio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares covered by capped calls.

+ References

No definition available.

+ Details

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Namespace Prefix:	bbio_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of principal amount to be repurchased in fundamental change.

+ References

No definition available.

+ Details

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Namespace Prefix:	bbio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Proceeds from issuance of notes after deducting discount and offering expenses.

+ References

No definition available.

+ Details

Name:	bbio_ProceedsFromIssuanceOfNotesAfterDeductingDiscountAndOfferingExpenses
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Purchase of capped calls.

+ References

No definition available.

+ Details

Name:	bbio_PurchaseOfCappedCalls
Namespace Prefix:	bbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Sale of stock premium over last reported sale price percentage.

+ References

No definition available.

+ Details

Name:	bbio_SaleOfStockPremiumOverLastReportedSalePricePercentage
Namespace Prefix:	bbio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold percentage of stock price trigger in measurement period.

+ References

No definition available.

+ Details

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Namespace Prefix:	bbio_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

+ References

+ Details

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

- Definition

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
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-Name Accounting Standards Codification
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-Paragraph 6
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(5))
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-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
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+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Subparagraph (b)
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-Topic 210
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(5))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentConvertibleThresholdTradingDays
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentDateOfFirstRequiredPayment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

+ Details

Name:	us-gaap_DebtInstrumentFrequencyOfPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the debt instrument was offered for sale, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

Name:	us-gaap_DebtInstrumentOfferingDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(3))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

Name:	us-gaap_DebtInstrumentPaymentTerms
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28555-108399

+ Details

Name:	us-gaap_DeferredFinanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 4
-Subparagraph (b)(3)
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-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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Debt - Additional Information (Details)						1 Months Ended		3 Months Ended			7 Months Ended	9 Months Ended
Debt - Additional Information (Details)	Jan. 28, 2021 USD ($) TradingDay shares $ / shares	Jan. 25, 2021 USD ($) $ / shares shares	Mar. 09, 2020 USD ($) TradingDay shares $ / shares	Mar. 04, 2020 USD ($) $ / shares shares	Nov. 30, 2019 USD ($)	Apr. 30, 2021 USD ($)	Apr. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jan. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	May 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)
Debt Instrument [Line Items]
Purchase of capped calls												$ 61,295,000	$ 49,280,000
Repurchase of common stock												198,458,000	75,000,000
Interest expense								$ 8,514,000			$ 18,429,000	$ 24,124,000
Hercules Capital, Inc
Debt Instrument [Line Items]
Debt instrument, frequency of interest payment						payable monthly
Stated interest rate						7.65%		7.65%				7.65%
Gains or losses on debt modification							$ 0
Debt instrument interest only extension date						Jun. 01, 2024
Debt instrument interest only extension date, one						Jun. 01, 2025
Debt instrument maturity date extension						May 01, 2025
Debt instrument amended maturity extended date						May 01, 2026
Debt instrument, additional available in loan facilities						$ 185,000.0		$ 185,000.0				$ 185,000.0
Debt instrument, additional increase available in loan facilities no later than June 15, 2022						70,000.0
Debt Instrument additional increase available in loan facilities upon achievement of certain performance milestones						40,000.0
Debt instrument, additional increase available in loan facilities no later than December 15, 2023						$ 75,000.0
Interest expense								2,500,000		$ 2,000,000.0		6,800,000	5,400,000
Amortization of debt discount and issuance costs								500,000		300,000		1,400,000	$ 1,000,000.0
Hercules Capital, Inc \| Prime Rate
Debt Instrument [Line Items]
Interest rate						4.40%
2029 Notes
Debt Instrument [Line Items]
Debt Instrument face amount	$ 717,500,000							747,500,000				$ 747,500,000
Proceeds from exercise of option to purchase additional notes	67,500,000
Debt instrument option to purchase additional notes	97,500,000
Proceeds from exercise of remaining portion of option to purchase additional notes	$ 30,000,000.0
Debt instrument issuance date	Jan. 28, 2021
Maturity year	2029
Debt instrument, frequency of interest payment	semiannually
Interest payable beginning date	Aug. 01, 2021
Stated interest rate	2.25%
Maturity date	Feb. 01, 2029
Description of payment terms of notes												The 2029 Notes will accrue interest payable semiannually in arrears on February 1 and August 1 of each year, beginning on August 1, 2021, at a rate of 2.25% per year. The 2029 Notes will mature on February 1, 2029, unless earlier converted, redeemed or repurchased.
Proceeds from issuance of notes after deducting discount and offering expenses	$ 731,400,000
Direct offering expense	0
Purchase of capped calls	61,300,000
Repurchase of common stock	50,000,000.0
Denomination of the principal amount of debt in consideration conversion of the notes	$ 1,000
Debt instrument, convertible, threshold trading days \| TradingDay	20
Debt instrument, convertible, threshold consecutive trading days \| TradingDay	30
Debt instrument, convertible, threshold percentage of stock price trigger	130.00%
Number of consecutive trading day period (Measurement period) for conversion of notes	5 days
Number of business days in consideration of conversion of notes	5 days
Threshold percentage of stock price trigger in measurement period	98.00%
Conversion rate	10.3050
Initial conversion price per share \| $ / shares	$ 97.04
Debt instrument, conversion, equivalent shares of common stock \| shares	7,702,988
Percentage of principal amount to be repurchased in fundamental change	100.00%
Minimum threshold percentage of aggregate principal by trustee or holders	25.00%
Debt issuance costs including initial purchasers discounts, legal and other professional fees	$ 16,100,000
Expected life of notes	8 years
Interest expense								4,662,000				$ 12,575,000
2029 Notes \| Maximum
Debt Instrument [Line Items]
Debt instrument, increase in conversion rate, number of shares issuable \| shares	11,361,851
2027 Notes
Debt Instrument [Line Items]
Debt Instrument face amount			$ 550,000,000.0					550,000,000.0				$ 550,000,000.0
Proceeds from exercise of option to purchase additional notes			$ 75,000,000.0
Debt instrument issuance date			Mar. 09, 2020
Maturity year			2027
Debt instrument, frequency of interest payment			semiannually
Interest payable beginning date			Sep. 15, 2020
Stated interest rate			2.50%
Maturity date			Mar. 15, 2027
Description of payment terms of notes												The 2027 Notes will accrue interest payable semiannually in arrears on March 15 and September 15 of each year, beginning on September 15, 2020, at a rate of 2.50% per year. The 2027 Notes will mature on March 15, 2027, unless earlier converted or repurchased
Proceeds from issuance of notes after deducting discount and offering expenses			$ 537,000,000.0
Purchase of capped calls			49,300,000
Repurchase of common stock			75,000,000.0
Denomination of the principal amount of debt in consideration conversion of the notes			$ 1,000
Debt instrument, convertible, threshold trading days \| TradingDay			20
Debt instrument, convertible, threshold consecutive trading days \| TradingDay			30
Debt instrument, convertible, threshold percentage of stock price trigger			130.00%
Number of consecutive trading day period (Measurement period) for conversion of notes			5 days
Number of business days in consideration of conversion of notes			5 days
Threshold percentage of stock price trigger in measurement period			98.00%
Conversion rate			23.4151
Initial conversion price per share \| $ / shares			$ 42.71
Debt instrument, conversion, equivalent shares of common stock \| shares			12,878,305
Percentage of principal amount to be repurchased in fundamental change			100.00%
Minimum threshold percentage of aggregate principal by trustee or holders			25.00%
Debt issuance costs including initial purchasers discounts, legal and other professional fees			$ 13,000,000.0					519,000				$ 519,000			$ 8,160,000
Expected life of notes			7 years
Debt instrument, convertible, if-converted value of notes in excess of principal amount												53,600,000
Debt issuance costs allocated to equity component			$ 4,100,000
Debt issuance costs allocated to liability component			$ 8,900,000
Interest expense								$ 3,852,000		$ 8,212,000		$ 11,549,000
2027 Notes \| Maximum
Debt Instrument [Line Items]
Debt instrument, increase in conversion rate, number of shares issuable \| shares			17,707,635
2021 Capped Call Transactions
Debt Instrument [Line Items]
Purchase of capped calls		$ 61,300,000
Initial conversion price per share \| $ / shares		$ 97.04
Capped call transaction, cap price per share \| $ / shares		$ 131.58
Premium over last reported sale price percentage		100.00%
Number of shares covered by capped calls \| shares		7,702,988
Adjustments to additional paid in capital related to premium payments									$ 61,300,000
2021 Capped Call Transactions \| Share Repurchase Transactions
Debt Instrument [Line Items]
Repurchase of common stock		$ 50,000,000.0
Stock repurchased during period, shares \| shares		759,993
Repurchase of common stock price per share \| $ / shares		$ 65.79
2020 Capped Call Transactions
Debt Instrument [Line Items]
Purchase of capped calls				$ 49,300,000
Initial conversion price per share \| $ / shares				$ 42.71
Capped call transaction, cap price per share \| $ / shares				$ 62.12
Premium over last reported sale price percentage				100.00%
Number of shares covered by capped calls \| shares				12,878,305
Adjustments to additional paid in capital related to premium payments				$ (49,300,000)
2020 Capped Call Transactions \| Share Repurchase Transactions
Debt Instrument [Line Items]
Repurchase of common stock				$ 75,000,000.0
Stock repurchased during period, shares \| shares				2,414,681
Repurchase of common stock price per share \| $ / shares				$ 31.06
Tranche I \| Hercules Capital, Inc
Debt Instrument [Line Items]
Debt Instrument face amount																		$ 35,000,000.0
Tranche II \| Hercules Capital, Inc
Debt Instrument [Line Items]
Debt Instrument face amount																	$ 20,000,000.0
Tranche III \| Hercules Capital, Inc
Debt Instrument [Line Items]
Debt Instrument face amount																$ 20,000,000.0
Tranche IV
Debt Instrument [Line Items]
Debt Instrument face amount														$ 25,000,000.0
Tranche IV \| Hercules Capital, Inc
Debt Instrument [Line Items]
Debt instrument additional principal borrowing amount						$ 25,000,000.0
Tranche A Loan \| Silicon Valley Bank and Hercules Loan Agreement
Debt Instrument [Line Items]
Interest rate												8.50%
Debt instrument drawn amount					$ 17,500,000
Tranche A Loan \| Silicon Valley Bank and Hercules Loan Agreement \| Eidos
Debt Instrument [Line Items]
Stated interest rate					8.50%
Maturity date					Oct. 02, 2023
Final payment charge percentage					5.95%
Tranche A Loan \| Silicon Valley Bank and Hercules Loan Agreement \| Prime Rate \| Eidos
Debt Instrument [Line Items]
Interest rate					3.25%
Tranche A Loan \| Maximum \| Silicon Valley Bank and Hercules Loan Agreement \| Eidos
Debt Instrument [Line Items]
Percentage of prepayment fee					2.50%
Tranche A Loan \| Minimum \| Silicon Valley Bank and Hercules Loan Agreement \| Eidos
Debt Instrument [Line Items]
Percentage of prepayment fee					0.75%