XML 48 R38.htm IDEA: XBRL DOCUMENT
v3.22.1

Derivatives - Summary of Terms of Derivative Financial Instrument (Details) - Cap Agreement - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2022 | Dec. 31, 2021
Derivative [Line Items] |  |
Notional Amount | $ 7,500,000 | $ 7,500,000
Strike | 3.75% |
Effective Date | Dec. 20, 2021 |
Maturity Date | Jul. 06, 2024 |

X
- Definition Derivative strike price percentage. + References No definition available. + Details
Name: | self_DerivativeStrikePricePercentage
Namespace Prefix: | self_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Date the entity entered into the derivative contract, in YYYY-MM-DD format. + References No definition available. + Details
Name: | us-gaap_DerivativeInceptionDates
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Date the derivative contract matures, in YYYY-MM-DD format. + References No definition available. + Details
Name: | us-gaap_DerivativeMaturityDates
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959 + Details
Name: | us-gaap_DerivativeNotionalAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateCapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |