XML 63 R53.htm IDEA: XBRL DOCUMENT
v3.24.0.1

DISTRIBUTIONS TO COMMON STOCKHOLDERS - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2023 | Sep. 30, 2023 | [1] | Jun. 30, 2023 | [1] | Dec. 31, 2022 | Sep. 30, 2022 | [1] | Jun. 30, 2022 | [1] | Dec. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2023
Equity [Abstract] |  |  |  |  |  |  |  |  |  |  |
Investment company, cash distributions paid to common stockholders from ordinary income | 53.20% |  |  |  |  |  |  |  | 53.20% |  |
Investment company, cash distributions paid to common stockholders from capital gains | 46.80% |  |  |  |  |  |  |  | 46.80% |  |
Cash distributions to common stockholders |  |  |  |  |  |  |  |  | $ 67,400 | $ 30,900 |
Distributions to common stockholders from ordinary income | $ 15,093 | [1] | $ 6,665 | $ 7,069 | $ 7,360 | [1] | $ 4,678 | $ 3,188 |  |  | $ 21,400
Distributions to common stockholders from net realized gains | 28,009 | [1] | $ 5,519 | $ 5,024 | 4,652 | [1] | $ 2,797 | $ 8,268 |  |  | $ 10,600
Investment company, net adjustments for tax difference to capital distribution | $ 400 |  |  |  | $ 300 |  |  |  | $ 400 | $ 1,600 |
[1] | Refer to Note 8 — Distributions to Common Stockholders in the accompanying Notes to Consolidated Financial Statements for additional information.

X
- Definition Investment Company, Cash Distributions Paid To Common Stockholders From Capital Gains, Percent + References No definition available. + Details
Name: | gain_InvestmentCompanyCashDistributionsPaidToCommonStockholdersFromCapitalGainsPercent
Namespace Prefix: | gain_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Investment Company, Cash Distributions Paid To Common Stockholders From Ordinary Income, Percent + References No definition available. + Details
Name: | gain_InvestmentCompanyCashDistributionsPaidToCommonStockholdersFromOrdinaryIncomePercent
Namespace Prefix: | gain_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Investment Company, Net Adjustments For Tax Difference To Capital Underdistribution + References No definition available. + Details
Name: | gain_InvestmentCompanyNetAdjustmentsForTaxDifferenceToCapitalUnderdistribution
Namespace Prefix: | gain_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 2 -SubTopic 405 -Topic 942 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481071/942-405-45-2 + Details
Name: | us-gaap_DividendsCommonStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_EquityAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of dividend distribution by investment company from long-term capital gain. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480990/946-20-50-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481004/946-505-50-5 + Details
Name: | us-gaap_InvestmentCompanyDistributionLongTermCapitalGain
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of dividend distribution by investment company from ordinary income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480990/946-20-50-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481004/946-505-50-5 + Details
Name: | us-gaap_InvestmentCompanyDistributionOrdinaryIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration