Debt - Schedule of Components (Details) - USD ($)	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Oct. 15, 2024	Aug. 16, 2024	Aug. 09, 2024	Nov. 17, 2023	Dec. 13, 2022
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	$ 3,084,000,000		$ 2,984,000,000
Principal Amount Outstanding	1,892,500,000		1,751,300,000
Principal Amount Available	541,488,000		717,844,000
Carrying value	1,900,691,000		1,745,999,000
Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	3,804,018,000		3,080,569,000
Senior Notes
Line of Credit Facility [Line Items]
Principal Amount Outstanding	715,000,000		615,000,000
ASPV Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	500,000,000		500,000,000			$ 500,000,000		$ 300,000,000
Principal Amount Outstanding	274,200,000		251,300,000
Principal Amount Available	58,956,000		69,062,000
Carrying Value	274,200,000		251,300,000
ASPV Credit Facility | Line of Credit | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	501,263,000		493,142,000
MSPV Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	500,000,000		500,000,000
Principal Amount Outstanding	363,100,000		191,400,000
Principal Amount Available	74,273,000		101,922,000
Carrying Value	363,100,000		191,400,000
MSPV Credit Facility | Line of Credit | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	707,695,000		505,122,000
Truist Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	975,000,000		975,000,000		$ 975,000,000		$ 300,000,000
Principal Amount Outstanding	146,200,000		299,600,000
Principal Amount Available	408,259,000		546,860,000
Carrying Value	146,200,000		299,600,000
Truist Credit Facility | Line of Credit | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	2,160,297,000		1,639,675,000
Series A Tranche A Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	90,000,000		90,000,000
Principal Amount Outstanding	90,000,000		90,000,000
Carrying Value	90,384,000		89,732,000
Series A Tranche A Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0		0
Series A Tranche B Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	150,000,000		150,000,000
Principal Amount Outstanding	150,000,000		150,000,000
Carrying Value	151,953,000		148,799,000
Series A Tranche B Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0		0
Series B Tranche A Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	85,000,000		85,000,000	$ 85,000,000
Principal Amount Outstanding	85,000,000		85,000,000
Carrying Value	86,092,000		84,330,000
Series B Tranche A Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0		0
Series B Tranche B Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	25,000,000		25,000,000	25,000,000
Principal Amount Outstanding	25,000,000		25,000,000
Carrying Value	25,000,000		25,000,000
Series B Tranche B Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0		0
Series B Tranche C Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	290,000,000		290,000,000	$ 290,000,000
Principal Amount Outstanding	290,000,000		290,000,000
Carrying Value	294,360,000		286,838,000
Series B Tranche C Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0		0
Series C Tranche A Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	25,000,000	$ 25,000,000
Principal Amount Outstanding	25,000,000
Carrying Value	25,324,000
Series C Tranche A Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0
Series C Tranche B Notes | Senior Notes
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	75,000,000	$ 75,000,000
Principal Amount Outstanding	75,000,000
Carrying Value	75,078,000
Series C Tranche B Notes | Senior Notes | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	0
CLO Transaction | Secured Debt
Line of Credit Facility [Line Items]
Maximum Principal Amount Committed	369,000,000		369,000,000
Principal Amount Outstanding	369,000,000		369,000,000
Principal Amount Available			0
Carrying Value	369,000,000		369,000,000
CLO Transaction | Secured Debt | Asset Pledged as Collateral
Line of Credit Facility [Line Items]
Assets Pledged as Collateral	$ 434,764,000		$ 442,629,000