v3.26.1
Financial Highlights - Schedule of Financial Highlights of the Company (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Dec. 31, 2024
Investment Company, Investment Income (Loss) from Operations, Per Share [Abstract]        
Net asset value, beginning of period [1] $ 8.07 $ 11.79    
Net investment income [1] 0.36 0.4    
Net realized gains (loss) [1] 0.19 0.02    
Net change in unrealized appreciation (depreciation) [1] (0.6) (0.38)    
Net increase (decrease) in net assets resulting from operations [1] (0.05) 0.04    
Issuance of common stock [1] 0 0    
Accretion from share buybacks [1] 0.02      
Distributions declared from net investment income [1],[2] (0.3) (0.37)    
Net increase (decrease) resulting from transactions with common stockholders [1] (0.28) (0.37)    
Net asset value, end of period [1] 7.74 11.46    
Per share market value, end of period [1] $ 5.01 $ 10.19    
Shares outstanding, end of period 13,892,045 [1] 11,544,415 [1] 13,998,168 11,544,415
Total return based on net asset value [1],[3] (0.37%) 0.34%    
Total return based on market value [1],[3] (24.63%) (3.91%)    
Ratio/Supplemental Data:        
Net assets, end of period $ 107,477 $ 132,295 $ 112,946 [4] $ 136,113
Ratio of total expenses to average net assets before waiver [5],[6],[7] 25.01% 20.88%    
Ratio of total expenses to average net assets after waiver [5],[6],[7] 22.52% 20.88%    
Ratio of net investment income to average net assets [5],[6],[7] 11.77% 16.12%    
Portfolio turnover 9.00% 8.00%    
[1] The per share data was derived by using the weighted average shares outstanding during the period, except where such calculations deviate from those specified under the instructions to Form N-2.
[2] The per share data for distributions declared reflects the actual amount of distributions of record per share for the period.
[3] Total return based on net asset value is calculated as the change in net asset value per share, assuming the Company’s distributions were reinvested through its dividend reinvestment plan. Total return based on market value is calculated as the change in market value per share, assuming the Company’s distributions were reinvested through its dividend reinvestment plan. Total return does not include any estimate of a sales load or commission paid to acquire shares.
[4] Great Elm Capital Corp.’s (the “Company”) investments are generally acquired in private transactions exempt from registration under the Securities Act, as amended (the “Securities Act”) and, therefore, are generally subject to limitations on resale, and may be deemed to be “restricted securities” under the Securities Act.
[5] Annualized for periods less than one year.
[6] Average net assets used in ratio calculations is calculated using monthly ending net assets for the period presented. For the three months ended March 31, 2026 and 2025 average net assets were $112,893 and $136,959, respectively.
[7] The ratio of incentive fees to average net assets was 0.48% and 0.84% for the three months ended March 31, 2026 and 2025, respectively