Annual report pursuant to Section 13 and 15(d)

Fair Value of Financial Instruments - Schedule of Fair Value Hierarchy Of Outstanding Borrowings (Details)

v3.25.0.1
Fair Value of Financial Instruments - Schedule of Fair Value Hierarchy Of Outstanding Borrowings (Details) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value $ 1,768,955 $ 1,554,869
Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 1,768,955 1,554,869
Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 1,713,360 1,450,995
SBA Debentures | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 271,371 170,323
SBA Debentures | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 260,436 142,011
July 2024 Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value   104,828
July 2024 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value   105,755
February 2025 Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 49,981 49,866
February 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 50,698 49,144
June 2025 Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 69,919 69,757
June 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 69,308 67,198
June 2025 3-Year Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 49,926 49,771
June 2025 3-Year Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 49,713 48,983
March 2026 A Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 49,889 49,795
March 2026 A Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 49,052 47,702
March 2026 B Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 49,880 49,776
March 2026 B Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 49,087 47,759
September 2026 Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 323,321 322,339
September 2026 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 302,244 288,711
January 2027 Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 347,265 345,935
January 2027 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 327,928 315,832
2031 Asset-Backed Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 118,769 148,544
2031 Asset-Backed Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 115,031 142,500
2033 Notes | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 39,043 38,935
2033 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 40,272 40,400
MUFG Bank Facility | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 116,000 61,000
MUFG Bank Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 116,000 61,000
SMBC Facility | Carrying Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Carrying value 283,591 94,000
SMBC Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 283,591 94,000
Identical Assets Level 1 | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | SBA Debentures | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | July 2024 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value   0
Identical Assets Level 1 | February 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | June 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | June 2025 3-Year Notes    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0  
Identical Assets Level 1 | June 2025 3-Year Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value   0
Identical Assets Level 1 | March 2026 A Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | March 2026 B Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | September 2026 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | January 2027 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | 2031 Asset-Backed Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | 2033 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | MUFG Bank Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Identical Assets Level 1 | SMBC Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 155,303 182,900
Observable Inputs Level 2 | SBA Debentures | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | July 2024 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value   0
Observable Inputs Level 2 | February 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | June 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | June 2025 3-Year Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | March 2026 A Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | March 2026 B Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | September 2026 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | January 2027 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | 2031 Asset-Backed Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 115,031 142,500
Observable Inputs Level 2 | 2033 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 40,272 40,400
Observable Inputs Level 2 | MUFG Bank Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Observable Inputs Level 2 | SMBC Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Unobservable Inputs Level 3 | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 1,558,057 1,268,095
Unobservable Inputs Level 3 | SBA Debentures | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 260,436 142,011
Unobservable Inputs Level 3 | July 2024 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value   105,755
Unobservable Inputs Level 3 | February 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 50,698 49,144
Unobservable Inputs Level 3 | June 2025 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 69,308 67,198
Unobservable Inputs Level 3 | June 2025 3-Year Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 49,713 48,983
Unobservable Inputs Level 3 | March 2026 A Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 49,052 47,702
Unobservable Inputs Level 3 | March 2026 B Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 49,087 47,759
Unobservable Inputs Level 3 | September 2026 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 302,244 288,711
Unobservable Inputs Level 3 | January 2027 Notes    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 327,928  
Unobservable Inputs Level 3 | January 2027 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value   315,832
Unobservable Inputs Level 3 | 2031 Asset-Backed Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Unobservable Inputs Level 3 | 2033 Notes | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 0 0
Unobservable Inputs Level 3 | MUFG Bank Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value 116,000 61,000
Unobservable Inputs Level 3 | SMBC Facility | Fair Value    
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]    
Approximate Fair Value $ 283,591 $ 94,000