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Schedule 12-14s - CONSOLIDATED SCHEDULE OF INVESTMENTS IN AND ADVANCES TO AFFILIATES (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | $ 460,668 | $ 321,688 | $ 280,976
Fair value beginning balance | 2,963,955 |  |
Total net change in unrealized appreciation (depreciation) | 25,010 | (85,063) | 3,311
Fair value ending balance | 3,248,046 | 2,963,955 |
Control investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 4,737 | 4,689 |
Realized Gain (Loss) | 0 | 0 | 0
Fair value beginning balance | 76,458 | 73,504 |
Gross Additions | 29,175 | 3,232 |
Gross Reductions | (13,263) | 0 |
Total net change in unrealized appreciation (depreciation) | 22,634 | (278) | (2,677)
Fair value ending balance | 115,004 | 76,458 | 73,504
Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 4,047 | 3,999 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 68,416 | 65,235 |
Gross Additions | 15,912 | 3,232 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | 19,159 | (51) |
Fair value ending balance | 103,487 | 68,416 | 65,235
Control investments | Other Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 690 | 690 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 8,042 | 8,269 |
Gross Additions | 13,263 | 0 |
Gross Reductions | (13,263) | 0 |
Total net change in unrealized appreciation (depreciation) | 3,475 | (227) |
Fair value ending balance | 11,517 | 8,042 | 8,269
Affiliate investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 1,204 |
Realized Gain (Loss) | 0 | 1,758 | (62,143)
Fair value beginning balance | 0 | 9,458 |
Gross Additions |  | 0 |
Gross Reductions |  | (13,547) |
Total net change in unrealized appreciation (depreciation) | 0 | 4,089 | 63,806
Fair value ending balance |  | 0 | 9,458
Investment Affiliated Issuers And Controlled Issuers |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 5,893 |
Realized Gain (Loss) |  | 1,758 |
Fair value beginning balance | 76,458 | 82,962 |
Gross Additions |  | 3,232 |
Gross Reductions |  | (13,547) |
Total net change in unrealized appreciation (depreciation) |  | 3,811 |
Fair value ending balance |  | 76,458 | 82,962
Coronado Aesthetics, LLC | Control investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Realized Gain (Loss) | 0 | 0 | 0
Fair value beginning balance | 319 | 565 |
Total net change in unrealized appreciation (depreciation) | (57) | (246) | 315
Fair value ending balance | 262 | 319 | 565
Gibraltar Acquisition LLC | Control investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Realized Gain (Loss) | 0 |  |
Total net change in unrealized appreciation (depreciation) | 9,656 |  |
Fair value ending balance | 62,512 |  |
Hercules Adviser LLC | Control investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Realized Gain (Loss) | 0 | 0 | 0
Fair value beginning balance | 31,153 | 20,840 |
Total net change in unrealized appreciation (depreciation) | 9,560 | 7,163 | 11,955
Fair value ending balance | 40,713 | 31,153 | 20,840
Tectura Corporation | Control investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Realized Gain (Loss) | 0 | 0 | 0
Fair value beginning balance | 8,042 | 8,269 |
Total net change in unrealized appreciation (depreciation) | 3,475 | (227) | (331)
Fair value ending balance | 11,517 | 8,042 | 8,269
Gibraltar Business Capital, LLC | Control investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Realized Gain (Loss) |  | 0 | 0
Fair value beginning balance | 36,944 | 43,830 |
Total net change in unrealized appreciation (depreciation) |  | (6,968) | (14,616)
Fair value ending balance |  | 36,944 | 43,830
Preferred Stock | Coronado Aesthetics, LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 0 | 0 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 313 | 500 |
Gross Additions | 0 | 0 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | (53) | (187) |
Fair value ending balance | 260 | 313 | 500
Preferred Stock | Tectura Corporation | Control investments | Other Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 0 | 0 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 0 | 0 |
Gross Additions | 13,263 | 0 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | (10,000) | 0 |
Fair value ending balance | 3,263 | 0 | 0
Preferred Stock | Gibraltar Business Capital, LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 0 |
Realized Gain (Loss) |  | 0 |
Fair value beginning balance | 14,137 | 19,393 |
Gross Additions |  | 0 |
Gross Reductions |  | 0 |
Total net change in unrealized appreciation (depreciation) |  | (5,256) |
Fair value ending balance |  | 14,137 | 19,393
Preferred Stock | Black Crow AI, Inc. | Affiliate investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 0 |
Realized Gain (Loss) |  | 3,772 |
Fair value beginning balance | 0 | 1,120 |
Gross Additions |  | 0 |
Gross Reductions |  | (1,000) |
Total net change in unrealized appreciation (depreciation) |  | (120) |
Fair value ending balance |  | 0 | 1,120
Common Stock | Coronado Aesthetics, LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 0 | 0 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 6 | 65 |
Gross Additions | 0 | 0 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | (4) | (59) |
Fair value ending balance | 2 | 6 | 65
Common Stock | Tectura Corporation | Control investments | Other Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 0 | 0 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 0 | 0 |
Gross Additions | 0 | 0 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | 4 | 0 |
Fair value ending balance | 4 | 0 | 0
Common Stock | Gibraltar Business Capital, LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 0 |
Realized Gain (Loss) |  | 0 |
Fair value beginning balance | 1,107 | 1,225 |
Gross Additions |  | 0 |
Gross Reductions |  | 0 |
Total net change in unrealized appreciation (depreciation) |  | (118) |
Fair value ending balance |  | 1,107 | 1,225
Common Stock | Pineapple Energy LLC | Affiliate investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 0 |
Realized Gain (Loss) |  | 0 |
Fair value beginning balance | 0 | 591 |
Gross Additions |  | 0 |
Gross Reductions |  | (4,767) |
Total net change in unrealized appreciation (depreciation) |  | 4,176 |
Fair value ending balance |  | 0 | 591
Member Units | Gibraltar Acquisition LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 0 |  |
Realized Gain (Loss) | 0 |  |
Fair value beginning balance | 15,244 |  |
Gross Additions | 6,000 |  |
Gross Reductions | 0 |  |
Total net change in unrealized appreciation (depreciation) | 6,790 |  |
Fair value ending balance | 28,034 | 15,244 |
Member Units | Hercules Adviser LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 0 | 0 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 19,153 | 11,990 |
Gross Additions | 0 | 0 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | 9,560 | 7,163 |
Fair value ending balance | 28,713 | 19,153 | 11,990
Unsecured Debt | Gibraltar Acquisition LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 3,439 |  |
Realized Gain (Loss) | 0 |  |
Fair value beginning balance | 21,700 |  |
Gross Additions | 9,912 |  |
Gross Reductions | 0 |  |
Total net change in unrealized appreciation (depreciation) | 2,866 |  |
Fair value ending balance | 34,478 | 21,700 |
Unsecured Debt | Hercules Adviser LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 608 | 546 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 12,000 | 8,850 |
Gross Additions | 0 | 3,150 |
Gross Reductions | 0 | 0 |
Total net change in unrealized appreciation (depreciation) | 0 | 0 |
Fair value ending balance | 12,000 | 12,000 | 8,850
Unsecured Debt | Gibraltar Business Capital, LLC | Control investments | Majority Owned Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 3,453 |
Realized Gain (Loss) |  | 0 |
Fair value beginning balance | 21,700 | 23,212 |
Gross Additions |  | 82 |
Gross Reductions |  | 0 |
Total net change in unrealized appreciation (depreciation) |  | (1,594) |
Fair value ending balance |  | 21,700 | 23,212
Senior Secured Debt | Tectura Corporation | Control investments | Other Control Investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income | 690 | 690 |
Realized Gain (Loss) | 0 | 0 |
Fair value beginning balance | 8,042 | 8,269 |
Gross Additions | 0 | 0 |
Gross Reductions | (13,263) | 0 |
Total net change in unrealized appreciation (depreciation) | 13,471 | (227) |
Fair value ending balance | 8,250 | 8,042 | 8,269
Senior Secured Debt | Pineapple Energy LLC | Affiliate investments |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Amount of Interest and Fees Credited to Income |  | 1,204 |
Realized Gain (Loss) |  | (2,014) |
Fair value beginning balance | $ 0 | 7,747 |
Gross Additions |  | 0 |
Gross Reductions |  | (7,780) |
Total net change in unrealized appreciation (depreciation) |  | 33 |
Fair value ending balance |  | $ 0 | $ 7,747

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