XML 39 R32.htm IDEA: XBRL DOCUMENT
v3.25.3

Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Significant Accounting Policies [Line Items] |  |
Percentage of investment company taxable income distribute to stockholders | 90.00% |
Percentage of net ordinary income | 98.00% |
Percentage of capital gain net income | 98.20% |
Percentage of excise tax on minimum distribution amount | 4.00% |
Accrued excise tax expense | $ 374 | $ 348
Federal |  |
Significant Accounting Policies [Line Items] |  |
Deferred tax assets, capital loss carryforwards |  | 181,545
Capital loss carryforward |  | 39,740
Capital loss carryforward, short-term |  | 16,815
Capital loss carryforward, long-term |  | $ 164,730
Maximum |  |
Significant Accounting Policies [Line Items] |  |
Percentage of aggregate investment fair value on total capitalization | 5.00% |
Percentage of individual investment fair value on total capitalization | 1.00% |

X
- Definition Capital loss carryforward. + References No definition available. + Details
Name: | gecc_CapitalLossCarryforward
Namespace Prefix: | gecc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Capital loss carryforward, long-term. + References No definition available. + Details
Name: | gecc_CapitalLossCarryforwardLongTerm
Namespace Prefix: | gecc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Capital loss carryforward, short-term. + References No definition available. + Details
Name: | gecc_CapitalLossCarryforwardShortTerm
Namespace Prefix: | gecc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage of aggregate investment fair value on market capitalization. + References No definition available. + Details
Name: | gecc_PercentageOfAggregateInvestmentFairValueOnMarketCapitalization
Namespace Prefix: | gecc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of capital gain net income. + References No definition available. + Details
Name: | gecc_PercentageOfCapitalGainNetIncome
Namespace Prefix: | gecc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of excise tax on minimum distribution amount. + References No definition available. + Details
Name: | gecc_PercentageOfExciseTaxOnMinimumDistributionAmount
Namespace Prefix: | gecc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of individual investment fair value on market capitalization. + References No definition available. + Details
Name: | gecc_PercentageOfIndividualInvestmentFairValueOnMarketCapitalization
Namespace Prefix: | gecc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of investment company taxable income. + References No definition available. + Details
Name: | gecc_PercentageOfInvestmentCompanyTaxableIncome
Namespace Prefix: | gecc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of net ordinary income. + References No definition available. + Details
Name: | gecc_PercentageOfNetOrdinaryIncome
Namespace Prefix: | gecc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Significant accounting policies. + References No definition available. + Details
Name: | gecc_SignificantAccountingPoliciesLineItems
Namespace Prefix: | gecc_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + Details
Name: | us-gaap_DeferredTaxAssetsCapitalLossCarryforwards
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount of excise and sales taxes included in sales and revenues, which are then deducted as a cost of sales. Includes excise taxes, which are applied to specific types of transactions or items (such as gasoline or alcohol); and sales, use and value added taxes, which are applied to a broad class of revenue-producing transactions involving a wide range of goods and services. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_ExciseAndSalesTaxes
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_DomesticCountryMember
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: |