Debt Covenant, Minimum Debt Service Reserves Required

No definition available.

Name:	be_DebtCovenantMinimumDebtServiceReservesRequired
Namespace Prefix:	be_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Debt Other Issuance Costs, Net

+ References

No definition available.

+ Details

Name:	be_DebtOtherIssuanceCostsNet
Namespace Prefix:	be_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: 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

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

+ Details

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

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types: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

Amount, after accumulated amortization, of debt premium.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399

+ Details

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

- Definition

Amount, before 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 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

+ Details

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

- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

+ Details

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

- Details

Name:	dei_LegalEntityAxis=be_PowerPurchaseAgreementCompany5Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=be_SeniorSecuredNotesDueJune2031NonRecourseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=be_SeniorSecuredNotesDueMarch2030NonRecourseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=be_PowerPurchaseAgreementCompany3aMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=be_TermLoanDueSeptember2028NonRecourseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=be_PowerPurchaseAgreementCompany4Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=be_TermLoanDueDecember2021NonRecourseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=be_TermLoandueDecember2021YearsOneThroughThreeNonRecourseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=be_TermLoandueDecember2021AfterYearThreeNonRecourseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Outstanding Loans and Security Agreements - Non-recourse Debt Facilities Narrative (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2021	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2012
Debt Instrument [Line Items]
Unpaid Principal Balance			$ 539,669,000	$ 527,054,000
PPA Company 5 \| Letters of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 6,200,000			$ 6,400,000
Senior secured notes \| 3.04% Senior Secured Notes due June 2031
Debt Instrument [Line Items]
Interest rate percentage				3.04%
Senior secured notes \| 6.07% Senior Secured Notes due March 2030
Debt Instrument [Line Items]
Interest rate percentage			6.07%	6.07%
Unpaid Principal Balance			$ 73,955,000	$ 77,837,000
Senior secured notes \| PPA Company 3a \| 3.04% Senior Secured Notes due June 2031
Debt Instrument [Line Items]
Interest rate percentage	3.04%
Unpaid Principal Balance	$ 109,100,000
Accrued interest	100,000
Financing fees	11,500,000
Debt instrument, unamortized premium	6,500,000
Debt other issuance costs, net	2,100,000
Proceeds from debt, net of issuance costs	6,700,000
Senior secured notes \| PPA Company 3a \| 7.5% Term Loan due September 2028
Debt Instrument [Line Items]
Interest rate percentage							7.50%
Debt face amount							$ 46,800,000
Debt minimum debt service reserves required			3,600,000	3,800,000
Senior secured notes \| PPA Company 4 \| 3.04% Senior Secured Notes due June 2031
Debt Instrument [Line Items]
Debt minimum debt service reserves required			8,000,000
Senior secured notes \| PPA Company 4 \| 6.07% Senior Secured Notes due March 2030
Debt Instrument [Line Items]
Interest rate percentage					6.07%
Debt minimum debt service reserves required			$ 9,100,000	$ 8,500,000
Senior secured notes \| PPA Company 5 \| 3.04% Senior Secured Notes due June 2031
Debt Instrument [Line Items]
Debt face amount	$ 136,000,000
Term loan \| LIBOR + 2.5% Term Loan due December 2021
Debt Instrument [Line Items]
Interest rate percentage			2.50%	2.50%
Debt face amount						$ 131,200,000
LIBOR margin (as a percentage)		2.50%
Unpaid Principal Balance				$ 114,761,000
Commitment fee percentage			0.50%
Term loan \| LIBOR + 2.5% Term Loan due December 2021 \| LIBOR
Debt Instrument [Line Items]
LIBOR margin (as a percentage)			2.50%
Term loan \| 7.5% Term Loan due September 2028
Debt Instrument [Line Items]
Interest rate percentage			7.50%	7.50%
Unpaid Principal Balance			$ 31,070,000	$ 34,456,000
Term loan \| PPA Company 5 \| Term Loan due December 2021, Years One Through Three, Non-Recourse \| LIBOR
Debt Instrument [Line Items]
LIBOR margin (as a percentage)			2.25%
Term loan \| PPA Company 5 \| Term Loan due December 2021, After Year Three, Non-Recourse \| LIBOR
Debt Instrument [Line Items]
LIBOR margin (as a percentage)			2.50%