XML 191 R171.htm IDEA: XBRL DOCUMENT v3.21.1

INCOME TAXES - Tax credit carry forwards (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
California Enterprise Zone tax credits
Tax Credit Carryforward [Line Items]
Tax credit carry forwards	$ 0.1	$ 0.1
Federal | Research and development tax credit
Tax Credit Carryforward [Line Items]
Tax credit carry forwards	0.7	1.0
State | Research and development tax credit
Tax Credit Carryforward [Line Items]
Tax credit carry forwards	$ 0.7	$ 1.0

X

- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319

+ Details

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

X

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

X

- Details

Name:	us-gaap_TaxCreditCarryforwardAxis=stem_CaliforniaEnterpriseZoneTaxCreditsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=us-gaap_DomesticCountryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_TaxCreditCarryforwardAxis=us-gaap_ResearchMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: