$BLUE
bluebird bio, Inc. Stock $blue

$blue Overview Financials Valuation SEC Filings Company Website

2020 Q2 Form 10-K Financial Statement

#000129397121000013 Filed on February 23, 2021

Income Statement

Concept	2020 Q2	2020	2019 Q4
Revenue	$0.00	$0.00	$9.997M
YoY Change	-100.0%		-48.05%
Cost Of Revenue	$1.554M	$5.396M	$1.100M
YoY Change	153.51%	81.2%	37.5%
Gross Profit	-$1.554M	-$5.396M	$8.900M
YoY Change	-112.25%	81.2%	-51.63%
Gross Profit Margin			89.03%
Selling, General & Admin	$68.63M	$240.0M	$76.20M
YoY Change	0.0%	1.74%	42.43%
% of Gross Profit			856.18%
Research & Development	$156.3M	$319.3M	$161.8M
YoY Change	6.67%	-2.39%	35.17%
% of Gross Profit			1817.98%
Depreciation & Amortization	$4.550M	$5.100M	$5.050M
YoY Change	12.35%	24.39%	10.99%
% of Gross Profit			56.74%
Operating Expenses	$224.9M	$559.3M	$238.0M
YoY Change	4.54%	-0.66%	35.07%
Operating Profit	-$143.7M	-$559.3M	-$230.5M
YoY Change	-29.13%	-0.66%	46.87%
Interest Expense	$2.939M	$5.770M	$5.500M
YoY Change	-68.69%	-66.8%	37.5%
% of Operating Profit
Other Income/Expense, Net	$1.551M	-$6.881M	$500.0K
YoY Change	-152.83%	-31.08%	-73.68%
Pretax Income	-$21.46M	-$560.4M	-$223.1M
YoY Change	-89.07%	0.86%	49.93%
Income Tax	$10.00K	$700.0K	$200.0K
% Of Pretax Income
Net Earnings	-$21.47M	-$618.7M	-$223.3M
YoY Change	-89.04%	-21.65%	49.87%
Net Earnings / Revenue			-2234.14%
Basic Earnings Per Share	-$0.36	-$9.95
Diluted Earnings Per Share	-$0.36	-$9.95	-$4.038M
COMMON SHARES
Basic Shares Outstanding	60.38M shares	62.18M shares
Diluted Shares Outstanding	60.38M shares	62.18M shares

Balance Sheet

Concept	2020 Q2	2020	2019 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.599B	$1.151B	$1.238B
YoY Change	3.7%	4.05%	-34.55%
Cash & Equivalents	$1.199B	$317.7M	$327.2M
Short-Term Investments	$400.0M	$833.5M	$910.8M
Other Short-Term Assets	$60.10M	$63.90M	$45.30M
YoY Change	65.11%	41.06%	34.42%
Inventory
Prepaid Expenses	$39.36M		$32.89M
Receivables	$4.000M	$400.0K	$400.0K
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.613B	$1.216B	$1.152B
YoY Change	24.04%	5.49%	-18.8%
LONG-TERM ASSETS
Property, Plant & Equipment	$155.4M	$346.9M	$151.2M
YoY Change	20.32%	2.91%	-38.7%
Goodwill	$13.13M		$13.13M
YoY Change	0.0%		0.0%
Intangibles	$12.18M		$14.33M
YoY Change	-26.07%		8.79%
Long-Term Investments	$49.40M	$122.9M	$131.5M
YoY Change	-82.84%	-6.54%	-74.02%
Other Assets	$74.78M	$72.80M	$79.23M
YoY Change	-11.94%	-8.08%	76.83%
Total Long-Term Assets	$494.3M	$565.8M	$575.3M
YoY Change	-31.58%	-1.63%	-30.18%
TOTAL ASSETS
Total Short-Term Assets	$1.613B	$1.216B	$1.152B
Total Long-Term Assets	$494.3M	$565.8M	$575.3M
Total Assets	$2.108B	$1.781B	$1.727B
YoY Change	4.17%	3.12%	-22.98%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$26.18M	$21.60M	$43.00M
YoY Change	-11.12%	-49.77%	141.13%
Accrued Expenses	$125.9M	$149.8M	$136.4M
YoY Change	44.22%	9.82%	41.05%
Deferred Revenue	$3.915M		$8.474M
YoY Change	-58.72%		-54.45%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due			$0.00
YoY Change			-100.0%
Total Short-Term Liabilities	$197.2M	$203.6M	$223.6M
YoY Change	21.63%	-8.94%	52.69%
LONG-TERM LIABILITIES
Long-Term Debt	$0.00	$0.00	$0.00
YoY Change			-100.0%
Other Long-Term Liabilities	$4.335M	$222.6M	$10.41M
YoY Change	155.15%	1.69%	235.18%
Total Long-Term Liabilities	$4.335M	$222.6M	$10.41M
YoY Change	155.15%	1.69%	235.18%
TOTAL LIABILITIES
Total Short-Term Liabilities	$197.2M	$203.6M	$223.6M
Total Long-Term Liabilities	$4.335M	$222.6M	$10.41M
Total Liabilities	$425.8M	$426.2M	$442.4M
YoY Change	10.02%	-3.66%	23.66%
SHAREHOLDERS EQUITY
Retained Earnings	-$2.506B		-$2.282B
YoY Change	35.27%		52.24%
Common Stock	$662.0K		$554.0K
YoY Change	19.71%		1.28%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.682B	$1.355B	$1.285B
YoY Change
Total Liabilities & Shareholders Equity	$2.108B	$1.781B	$1.727B
YoY Change	4.17%	3.12%	-22.98%

Cashflow Statement

Concept	2020 Q2	2020	2019 Q4
OPERATING ACTIVITIES
Net Income	-$21.47M	-$618.7M	-$223.3M
YoY Change	-89.04%	-21.65%	49.87%
Depreciation, Depletion And Amortization	$4.550M	$5.100M	$5.050M
YoY Change	12.35%	24.39%	10.99%
Cash From Operating Activities	$39.74M	-$470.4M	-$159.0M
YoY Change	-128.82%	-16.66%	22.54%
INVESTING ACTIVITIES
Capital Expenditures	-$4.800M	$28.99M	-$13.39M
YoY Change	-74.21%	-59.19%	3.8%
Acquisitions
YoY Change
Other Investing Activities	$274.1M	-$55.36M	$196.6M
YoY Change	9.18%	-109.48%	-148.17%
Cash From Investing Activities	$269.3M	-$84.35M	$183.3M
YoY Change	15.85%	-116.61%	-143.52%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net	$541.5M
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	543.1M	$546.7M	2.010M
YoY Change	11262.55%	2480.43%	4.69%
NET CHANGE
Cash From Operating Activities	39.74M	-$470.4M	-159.0M
Cash From Investing Activities	269.3M	-$84.35M	183.3M
Cash From Financing Activities	543.1M	$546.7M	2.010M
Net Change In Cash	852.1M	-$7.981M	26.30M
YoY Change	757.97%	-77.45%	-104.79%
FREE CASH FLOW
Cash From Operating Activities	$39.74M	-$470.4M	-$159.0M
Capital Expenditures	-$4.800M	$28.99M	-$13.39M
Free Cash Flow	$44.54M	-$499.3M	-$145.6M
YoY Change	-137.34%	-21.42%	24.61%

Facts In Submission

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CY2020	us-gaap	Nature Of Operations NatureOfOperations	Description of the business<div style="margin-top:6pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">bluebird bio, Inc. (the “Company” or “bluebird”) was incorporated in Delaware on April 16, 1992, and is headquartered in Cambridge, Massachusetts. The Company is a biotechnology company committed to researching, developing and commercializing potentially transformative gene therapies for severe genetic diseases and cancer. Since its inception, the Company has devoted substantially all of its resources to its research and development efforts relating to its product candidates, including activities to manufacture product candidates, conduct clinical studies of its product candidates, perform preclinical research to identify new product candidates and provide selling, general and administrative support for these operations, including commercial-readiness activities.</span></div><div style="margin-top:12pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company’s programs in severe genetic diseases include betibeglogene autotemcel (beti-cel; formerly LentiGlobin for β-thalassemia gene therapy) as a treatment for transfusion-dependent β-thalassemia, or TDT; its LentiGlobin</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">®</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> product candidate as a treatment for sickle cell disease, or SCD; and elivaldogene autotemcel (eli-cel; formerly Lenti-D gene therapy) as a treatment for cerebral adrenoleukodystrophy, or CALD. The Company’s programs in oncology are focused on developing novel T cell-based immunotherapies, including chimeric antigen receptor (CAR) and T cell receptor (TCR) T cell therapies. Idecabtagene vicleucel, or ide-cel, and bb21217 are product candidates in oncology under the Company’s collaboration arrangement with Bristol-Myers Squibb ("BMS"). ide-cel and bb21217 are CAR T cell product candidates for the treatment of multiple myeloma. Please refer to Note 11, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Collaborative arrangements,</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> for further discussion of the Company’s collaboration with BMS.</span></div><div style="margin-top:12pt;text-indent:18pt"><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In June 2019, the Company received conditional marketing authorization from the European Commission for beti-cel as a treatment of patients 12 years and older with TDT who do not have a β</span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">0</span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">/β</span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">0</span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> genotype, for whom hematopoietic stem cell (HSC) transplantation is appropriate but a human leukocyte-matched related HSC donor is not available. beti-cel is being marketed as ZYNTEGLO™ in the European Union. Since receiving conditional marketing authorization for ZYNTEGLO, the Company has continued to advance its commercial readiness activities. Through December 31, 2020, the Company had not generated any revenue from product sales. In February 2021 the Company temporarily suspended marketing of ZYNTEGLO in light of safety events in the HGB-206 study of LentiGlobin gene therapy for SCD which is manufactured using the same vector as ZYNTEGLO. Additionally, the European Medicines Agency, or EMA, has paused the renewal procedure for ZYNTEGLO's conditional marketing authorization while the EMA's pharmacovigilance risk assessment committee reviews the risk-benefit assessment for ZYNTEGLO and determines whether any additional pharmacovigilance measures are necessary. </span></div><div style="margin-top:12pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In January 2021, the Company announced its intent to separate its severe genetic disease and oncology programs into two separate, independent publicly traded companies, bluebird bio, Inc. and a new company, referred to as Oncology NewCo in these consolidated financial statements. bluebird bio, Inc. intends to retain focus on its severe genetic disease programs and Oncology NewCo is expected to focus on the Company's oncology programs. The transaction is expected to be completed in late 2021 and is anticipated to be tax-free, subject to receipt of a favorable Internal Revenue Service (“IRS”) ruling.</span></div><div style="margin-top:12pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In accordance with Accounting Standards Codification (“ASC”) 205-40, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Going Concern</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that the consolidated financial statements are issued. The Company has incurred losses since inception and to date has financed its operations primarily through the sale of equity securities and, to a lesser extent, through collaboration agreements and grants from governmental agencies and charitable foundations. As of December 31, 2020, the Company had an accumulated deficit of $2.90 billion. During the year ended December 31, 2020, the Company incurred a loss of $618.7 million and used $470.4 million of cash in operations. The Company expects to continue to generate operating losses and negative operating cash flows for the next few years and will need additional funding to support its planned operating activities through profitability. The transition to profitability is dependent upon the successful development, approval, and commercialization of the Company’s products and product candidates and the achievement of a level of revenues adequate to support its cost structure. </span></div><div style="margin-top:12pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">As of December 31, 2020, the Company had cash, cash equivalents and marketable securities of $1.27 billion. The Company expects its cash, cash equivalents and marketable securities will be sufficient to fund current planned operations for at least the next twelve months from the date of issuance of these financial statements, though it may pursue additional cash resources through public or private equity or debt financings or by establishing additional collaborations with other companies. Management's expectations with respect to its ability to fund current planned operations is based on estimates that are subject to </span></div>risks and uncertainties. If actual results are different from management's estimates, the Company may need to seek additional strategic or financing opportunities sooner than would otherwise be expected. However, there is no guarantee that any of these strategic or financing opportunities will be executed or executed on favorable terms, and some could be dilutive to existing stockholders. If the Company is unable to obtain additional funding on a timely basis, it may be forced to significantly curtail, delay, or discontinue one or more of its planned research or development programs or be unable to expand its operations or otherwise capitalize on its commercialization of its product and product candidates.
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CY2019Q4	us-gaap	Marketable Securities MarketableSecurities	910752000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of estimates</span></div><div style="margin-top:6pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the financial statements and accompanying notes. Actual results could materially differ from those estimates. Management considers many factors in selecting appropriate financial accounting policies and controls, and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including: expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes and management must select an amount that falls within that range of reasonable estimates. This process may result in actual results differing materially from those estimated amounts used in the preparation of the financial statements.</span></div><div style="margin-top:12pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Estimates and judgments are used in the following areas, among others: future undiscounted cash flows and subsequent fair value estimates used to assess potential and measure any impairment of long-lived assets, including goodwill and intangible assets, and the measurement of right-of-use assets and lease liabilities, contingent consideration, stock-based compensation expense, accrued expenses, income taxes, and the assessment of the Company's ability to fund its operations for at least the next twelve months from the date of issuance of these financial statements. In addition, estimates and judgments are used in the Company’s accounting for its revenue-generating arrangements, in particular as it relates to determining the standalone selling price of performance obligations, evaluating whether an option to acquire additional goods and services represents a material right, estimating the total transaction price, including estimating variable consideration and the probability of achieving future potential development and regulatory milestones, assessing the period of performance over which revenue may be recognized, and accounting for modifications to revenue-generating arrangements.</span></div>
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="margin-top:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Concentrations of credit risk and off-balance sheet risk</span></div><div style="margin-top:6pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Financial instruments that subject the Company to credit risk primarily consist of cash and cash equivalents and available-for-sale securities. The Company maintains its cash and cash equivalent balances with high-quality financial institutions and, consequently, the Company believes that such funds are subject to minimal credit risk. The Company’s marketable securities primarily consist of U.S. Treasury securities, U.S. government agency securities, certificates of deposit, corporate bonds, and commercial paper, and potentially subject the Company to concentrations of credit risk. The Company has adopted an investment policy that limits the amounts the Company may invest in any one type of investment and requires all investments held by the Company to be at least AA+/Aa1 rated, thereby reducing credit risk exposure.</span></div>
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2020	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	11500000	USD
CY2019	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	34800000	USD
CY2018	us-gaap	Investment Income Net Amortization Of Discount And Premium InvestmentIncomeNetAmortizationOfDiscountAndPremium	30100000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0.0	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0.0	USD
CY2018	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	15500000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	20017000	USD
CY2020Q4	blue	Equity Securities Unrealized Gain EquitySecuritiesUnrealizedGain	0	USD
CY2020Q4	blue	Equity Securities Unrealized Loss EquitySecuritiesUnrealizedLoss	14364000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	5653000	USD
CY2020Q4	blue	Marketable Securities Amortized Cost MarketableSecuritiesAmortizedCost	970180000	USD
CY2020Q4	blue	Marketable Securities Unrealized Gains MarketableSecuritiesUnrealizedGains	735000	USD
CY2020Q4	blue	Marketable Securities Unrealized Loss MarketableSecuritiesUnrealizedLoss	14478000	USD
CY2020Q4	us-gaap	Marketable Securities MarketableSecurities	956437000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	20017000	USD
CY2019Q4	blue	Equity Securities Unrealized Gain EquitySecuritiesUnrealizedGain	0	USD
CY2019Q4	blue	Equity Securities Unrealized Loss EquitySecuritiesUnrealizedLoss	7147000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	12870000	USD
CY2019Q4	blue	Marketable Securities Amortized Cost MarketableSecuritiesAmortizedCost	915152000	USD
CY2019Q4	blue	Marketable Securities Unrealized Gains MarketableSecuritiesUnrealizedGains	2838000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	0	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	0	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	0	USD
CY2020Q4	us-gaap	Interest Receivable InterestReceivable	3100000	USD
CY2019Q4	us-gaap	Interest Receivable InterestReceivable	3600000	USD
CY2019	blue	Interest Receivable Write Off InterestReceivableWriteOff	0	USD
CY2020	blue	Interest Receivable Write Off InterestReceivableWriteOff	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	287982000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	114000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	1205000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	289187000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	114000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	67217000	USD
CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	46000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	79618000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	45000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	146835000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	91000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	5700000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	12900000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	213891000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	187749000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	51060000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	36573000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	162831000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	151176000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	15100000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	13400000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	13400000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	56023000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	54495000	USD
CY2020Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	55802000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	44679000	USD
CY2020Q4	blue	Accrued Manufacturing Costs Current AccruedManufacturingCostsCurrent	22571000	USD
CY2019Q4	blue	Accrued Manufacturing Costs Current AccruedManufacturingCostsCurrent	23126000	USD
CY2020Q4	blue	Accrued Clinical And Contract Research Organization Costs Current AccruedClinicalAndContractResearchOrganizationCostsCurrent	23766000	USD
CY2019Q4	blue	Accrued Clinical And Contract Research Organization Costs Current AccruedClinicalAndContractResearchOrganizationCostsCurrent	16799000	USD
CY2020Q4	blue	Accrued Collaboration Research Costs Current AccruedCollaborationResearchCostsCurrent	20004000	USD
CY2019Q4	blue	Accrued Collaboration Research Costs Current AccruedCollaborationResearchCostsCurrent	27142000	USD
CY2020Q4	blue	Accrued Property Plant And Equipment Current AccruedPropertyPlantAndEquipmentCurrent	789000	USD
CY2019Q4	blue	Accrued Property Plant And Equipment Current AccruedPropertyPlantAndEquipmentCurrent	2354000	USD
CY2020Q4	blue	Accrued License And Milestone Fees AccruedLicenseAndMilestoneFees	278000	USD
CY2019Q4	blue	Accrued License And Milestone Fees AccruedLicenseAndMilestoneFees	300000	USD
CY2020Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	1541000	USD
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	66400000	shares
CY2019Q4	us-gaap	Accrued Professional Fees Current AccruedProfessionalFeesCurrent	1827000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	20655000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	25329000	USD
CY2020Q4	us-gaap	Accrued Liabilities And Other Liabilities AccruedLiabilitiesAndOtherLiabilities	145406000	USD
CY2019Q4	us-gaap	Accrued Liabilities And Other Liabilities AccruedLiabilitiesAndOtherLiabilities	141556000	USD
CY2019Q2	blue	Lessee Operating Lease Annual Rent Increase Percentage LesseeOperatingLeaseAnnualRentIncreasePercentage	0.03
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	35049000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	35346000	USD
CY2020	us-gaap	Lease Cost LeaseCost	35049000	USD
CY2019	us-gaap	Lease Cost LeaseCost	35346000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	32097000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	31026000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y4M24D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y4M24D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0635
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0670
CY2020	us-gaap	Operating Lease Expense OperatingLeaseExpense	47700000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	45300000	USD
CY2018	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	9800000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	36430000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	36899000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	37387000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	37398000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	32082000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	56095000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	236291000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	43270000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	193021000	USD
CY2020Q4	us-gaap	Purchase Obligation Due In Next Twelve Months PurchaseObligationDueInNextTwelveMonths	83885000	USD
CY2020Q4	us-gaap	Purchase Obligation Due In Second Year PurchaseObligationDueInSecondYear	12611000	USD
CY2020Q4	us-gaap	Purchase Obligation Due In Third Year PurchaseObligationDueInThirdYear	0	USD
CY2020Q4	us-gaap	Purchase Obligation Due In Fourth Year PurchaseObligationDueInFourthYear	0	USD
CY2020Q4	us-gaap	Purchase Obligation Due In Fifth Year PurchaseObligationDueInFifthYear	0	USD
CY2020Q4	us-gaap	Purchase Obligation Due After Fifth Year PurchaseObligationDueAfterFifthYear	0	USD
CY2020Q4	us-gaap	Purchase Obligation PurchaseObligation	96496000	USD
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	125000000.0	shares
CY2020Q4	blue	Common Stock Number Of Votes Per Common Share CommonStockNumberOfVotesPerCommonShare	1	vote
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	66400000	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	55400000	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	55400000	shares
CY2018Q1	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	300000	shares
CY2018Q1	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	185.00
CY2018Q1	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	48700000	USD
CY2018Q3	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	3900000	shares
CY2018Q3	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	162.50
CY2018Q3	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	600600000	USD
CY2018Q3	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	400000	shares
CY2018Q3	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	238.10
CY2018Q3	us-gaap	Proceeds From Issuance Or Sale Of Equity ProceedsFromIssuanceOrSaleOfEquity	100000000.0	USD
CY2018Q3	blue	Common Stock Amount Attributable To Prepayment Of Joint Research Activities CommonStockAmountAttributableToPrepaymentOfJointResearchActivities	45500000	USD
CY2020Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	10500000	shares
CY2020Q2	us-gaap	Shares Issued Price Per Share SharesIssuedPricePerShare	55.00
CY2020Q2	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	541500000	USD
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	5000000.0	shares
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2020Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	10369000	shares
CY2019Q4	us-gaap	Common Stock Capital Shares Reserved For Future Issuance CommonStockCapitalSharesReservedForFutureIssuance	8764000	shares
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	35324000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	25283000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	10041000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	35324000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	20998000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	14326000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4300000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	4100000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	3800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	4285000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	2404000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	522000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	522000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	522000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	1786000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	10041000	USD
CY2020Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Other Increases Decreases In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherIncreasesDecreasesInPeriod	2200000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	2600000	shares
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	156600000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	160600000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	110800000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	156631000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	160629000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	110836000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	156631000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	160629000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	110836000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.695
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.707
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.755
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.014
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.023
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.027
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.000
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.000
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.000
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	5483000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	116.30
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	1585000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	69.40
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	95000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	19.43
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod	711000	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice	124.00
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	6262000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	105.02
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	15716000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	3669000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	107.11
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P5Y9M18D
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	15659000	USD
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CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-790153000	USD
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CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	612000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	222000	USD
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CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-966000	USD
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CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	0	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-198000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-52000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
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CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	686000	USD
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CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Percent	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Cuts And Jobs Act Of2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsAndJobsActOf2017Percent	0.001
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.003
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.008
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.001
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CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.256
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CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	700000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.001
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-500000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.001
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	200000	USD
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.000
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	546098000	USD
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CY2020Q4	blue	Deferred Tax Assets Capitalized License Fee And Research And Development Expenses DeferredTaxAssetsCapitalizedLicenseFeeAndResearchAndDevelopmentExpenses	14402000	USD
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CY2020Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	45976000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	49480000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	7576000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	882879000	USD
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CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	0	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	0	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	138300000	USD
CY2020Q4	blue	Operating Loss Carryforwards Without Expiration Dates OperatingLossCarryforwardsWithoutExpirationDates	1320000000	USD
CY2020Q4	blue	Operating Loss Carryforwards With Expiration Dates OperatingLossCarryforwardsWithExpirationDates	711000000.0	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	12095000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	3554000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	296000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15945000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	3149000	USD
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CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	18994000	USD
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CY2020Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	0	USD
CY2019Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	0	USD
CY2020Q4	us-gaap	Costs And Expenses CostsAndExpenses	214690000	USD
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	8083000	shares
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CY2020Q1	us-gaap	Revenues Revenues	21863000	USD
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CY2020	us-gaap	Revenues Revenues	250734000	USD
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CY2019	us-gaap	Net Income Loss NetIncomeLoss	-789608000	USD
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2020 Q2 Form 10-K Financial Statement

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2020 Q2 Form 10-K Financial Statement

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