XML 244 R224.htm IDEA: XBRL DOCUMENT
v3.21.1

WARRANTS (Details) - $ / shares | Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Class of Warrant or Right [Line Items] |  |  |
Number of Shares (in shares) | 44,205,800 | 44,296,242 | 29,624,663
Minimum |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price |  | $ 0.36 | $ 0.36
Warrant term |  | 1 year | 1 year
Maximum |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price |  | $ 1.53 | $ 1.53
Warrant term | 6 years | 5 years | 5 years
Series A' |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price | $ 0.4485 |  |
Number of Shares (in shares) | 178,372 |  |
Warrant term | 10 years |  |
Series D |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price | $ 1.5326 |  |
Number of Shares (in shares) | 6,157,542 |  |
Warrant term | 7 years |  |
Series D' |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price | $ 1.5326 |  |
Number of Shares (in shares) | 37,869,886 |  |
Warrant term | 7 years |  |
Shares reserved for warrants to purchase shares of common stock |  |  |
Class of Warrant or Right [Line Items] |  |  |
Number of Shares (in shares) | 6,001,639 | 6,001,639 | 6,001,639
Shares reserved for warrants to purchase shares of common stock | Minimum |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price | $ 0.36 |  |
Warrant term | 1 year |  |
Shares reserved for warrants to purchase shares of common stock | Maximum |  |  |
Class of Warrant or Right [Line Items] |  |  |
Exercise price | $ 1.53 |  |

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
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_ClassOfWarrantOrRightLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of warrants or rights outstanding. + References No definition available. + Details
Name: | us-gaap_ClassOfWarrantOrRightOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_WarrantsAndRightsOutstandingTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=stem_SeriesAPlusConvertiblePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=stem_SeriesDConvertiblePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=stem_SeriesDPlusConvertiblePreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=stem_CommonStockWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |