Consolidated Statements of Changes in Net Assets - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Operations:
Net investment income	$ 61,642	$ 18,908	$ 151,374	$ 40,809
Net unrealized appreciation (depreciation)	(3,198)	6,783	13,066	11,995
Net realized gains (losses)	(59)	(476)	3,741	(2,877)
Provision for income tax (expense) benefit	(158)	(71)	(543)	(176)
Net increase (decrease) in net assets resulting from operations	58,227	25,144	167,638	49,751
Distributions to common shareholders:
Net decrease in net assets resulting from distributions	(68,254)	(21,422)	(171,702)	(47,641)
Share transactions:
Issuance of Common shares in public offering	417,046	282,257
Issuance of Common shares under dividend reinvestment plan	18,165	4,115	45,869	8,770
Repurchased shares, net of early repurchase deduction	(16,544)	(40)
Total increase (decrease) in net assets	408,640	290,054	1,350,181	648,187
Net assets at beginning of period	2,470,746	724,860	1,529,205	366,727
Net assets at end of period	$ 2,879,386	$ 1,014,914	$ 2,879,386	$ 1,014,914
Net asset value per common share (in dollars per share)	$ 23.53	$ 23.48	$ 23.53	$ 23.48
Common shares outstanding at end of period (in shares)	122,364,000	43,219,000	122,364,000	43,219,000
Common Class I
Distributions to common shareholders:
Net decrease in net assets resulting from distributions	$ (46,748)	$ (15,241)	$ (118,282)	$ (35,805)
Share transactions:
Issuance of Common shares in public offering	271,288	164,300	881,665	381,028
Share transfers between classes	112	0	364	0
Issuance of Common shares under dividend reinvestment plan	7,687	1,797	20,839	4,264
Repurchased shares, net of early repurchase deduction	(7,296)	0	(21,838)	0
Net increase from share transactions	$ 271,791	$ 166,097	$ 881,030	$ 385,292
Net asset value per common share (in dollars per share)	$ 23.53	$ 23.48	$ 23.53	$ 23.48
Common shares outstanding at end of period (in shares)	81,487,000	29,495,000	81,487,000	29,495,000
Common Class S
Distributions to common shareholders:
Net decrease in net assets resulting from distributions	$ (21,469)	$ (6,181)	$ (53,349)	$ (11,836)
Share transactions:
Issuance of Common shares in public offering	145,291	117,942	460,437	256,304
Share transfers between classes	(112)	0	(364)	0
Issuance of Common shares under dividend reinvestment plan	10,458	2,318	24,999	4,506
Repurchased shares, net of early repurchase deduction	(9,248)	(40)	(13,449)	(40)
Net increase from share transactions	$ 146,389	$ 120,220	$ 471,623	$ 260,770
Net asset value per common share (in dollars per share)	$ 23.53	$ 23.48	$ 23.53	$ 23.48
Common shares outstanding at end of period (in shares)	40,803,000	13,723,000	40,803,000	13,723,000
Common Class D
Distributions to common shareholders:
Net decrease in net assets resulting from distributions	$ (37)	$ 0	$ (71)	$ 0
Share transactions:
Issuance of Common shares in public offering	467	15	1,561	15
Issuance of Common shares under dividend reinvestment plan	20	0	31	0
Repurchased shares, net of early repurchase deduction			0	0
Net increase from share transactions	$ 487	$ 15	$ 1,592	$ 15
Net asset value per common share (in dollars per share)	$ 23.53	$ 23.48	$ 23.53	$ 23.48
Common shares outstanding at end of period (in shares)	74,000	1,000	74,000	1,000