Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Feb. 28, 2019
Document Information [Line Items]
Entity Registrant Name	Bloom Energy Corp
Entity Central Index Key	0001664703
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Emerging Growth Company	true
Entity Small Business	false
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float	$ 156,000,000
Class A common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		58,462,298
Class B common stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		54,442,364