Fair Value Measurement and Disclosures - Summary of Fair Value of Level III Investments (Details) - USD ($) |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Net change in unrealized gain (loss) | $ (10,793,000) | $ 1,581,000 | $ (21,446,000) | $ 736,000 |
| Transfers out of Level III | 0 | |||
| Level III | ||||
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Balance, beginning | 1,480,686,000 | 356,705,000 | 1,068,004,000 | 73,377,000 |
| Purchases | 624,609,000 | 340,774,000 | 1,858,668,000 | 729,101,000 |
| Sales | (581,954,000) | (66,246,000) | (1,391,892,000) | (173,469,000) |
| Net realized gain (loss) | (267,000) | 4,448,000 | 626,000 | 4,449,000 |
| Net change in unrealized gain (loss) | (10,793,000) | (1,581,000) | (21,446,000) | 736,000 |
| Transfers into Level III | 0 | 140,478,000 | 0 | 140,478,000 |
| Transfers out of Level III | (57,491,000) | 0 | (59,170,000) | (94,000) |
| Balance, ending | 1,454,790,000 | 774,578,000 | 1,454,790,000 | 774,578,000 |
| Series I | ||||
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Net change in unrealized gain (loss) | (1,718,000) | (1,237,000) | (4,015,000) | (2,359,000) |
| Transfers into Level III | 34,264,000 | 34,264,000 | ||
| Transfers out of Level III | (11,141,000) | (11,468,000) | (27,000) | |
| Series I | Level III | ||||
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Balance, beginning | 237,892,000 | 87,006,000 | 207,000,000 | 21,331,000 |
| Purchases | 89,279,000 | 59,072,000 | 246,093,000 | 151,928,000 |
| Sales | (86,724,000) | (10,426,000) | (210,150,000) | (36,457,000) |
| Net realized gain (loss) | (43,000) | 51,000 | 85,000 | 50,000 |
| Net change in unrealized gain (loss) | (1,718,000) | (1,237,000) | (4,015,000) | (2,359,000) |
| Transfers into Level III | 0 | 34,264,000 | 0 | 34,264,000 |
| Transfers out of Level III | (11,141,000) | 0 | (11,468,000) | (27,000) |
| Balance, ending | 227,545,000 | 168,730,000 | 227,545,000 | 168,730,000 |
| Series II | ||||
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Net change in unrealized gain (loss) | (9,075,000) | 344,000 | (17,431,000) | 3,095,000 |
| Transfers into Level III | 106,214,000 | 106,214,000 | ||
| Transfers out of Level III | (46,350,000) | (47,702,000) | (67,000) | |
| Series II | Level III | ||||
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
| Balance, beginning | 1,242,794,000 | 269,699,000 | 861,004,000 | 52,046,000 |
| Purchases | 535,330,000 | 281,702,000 | 1,612,575,000 | 577,173,000 |
| Sales | (495,230,000) | (55,820,000) | (1,181,742,000) | (137,012,000) |
| Net realized gain (loss) | (224,000) | 4,397,000 | 541,000 | 4,399,000 |
| Net change in unrealized gain (loss) | (9,075,000) | (344,000) | (17,431,000) | 3,095,000 |
| Transfers into Level III | 0 | 106,214,000 | 0 | 106,214,000 |
| Transfers out of Level III | (46,350,000) | 0 | (47,702,000) | (67,000) |
| Balance, ending | $ 1,227,245,000 | $ 605,848,000 | $ 1,227,245,000 | $ 605,848,000 |