Share-based Compensation Arrangement by Share-based Payment Award, Options And Non-Option Equity Instruments, Outstanding, Number

No definition available.

+ Details

Name:	blcm_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsAndNonOptionEquityInstrumentsOutstandingNumber
Namespace Prefix:	blcm_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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_ShareBasedGoodsAndNonemployeeServicesTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_AwardTypeAxis=blcm_InducementEmployeeStockOptionsMember
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- Details

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- Details

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STOCKHOLDERS' EQUITY AND SHARE-BASED COMPENSATION PLANS - Outstanding Awards (Details) - shares	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Goods and Nonemployee Services Transaction [Line Items]
Options outstanding (in shares)	567,842	575,924	528,647
2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Awards outstanding (in shares)	574,201	548,650
Stock options \| 2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Options outstanding (in shares)	471,282	401,535
Inducement stock options \| 2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Options outstanding (in shares)	96,560	122,500
Restricted stock units \| 2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Awards other than options outstanding (in shares)	5,609	19,490
Inducement restricted stock units outstanding \| 2019 Equity Incentive Plan
Share-based Goods and Nonemployee Services Transaction [Line Items]
Awards other than options outstanding (in shares)	750	5,125