Financial Highlights (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Investment Company, Financial Highlights [Roll Forward]
Net asset value at beginning of period (in dollars per share)	$ 23.09
Net asset value at end of period (in dollars per share)	$ 22.93	$ 23.52
Common shares outstanding at beginning of period (in shares)	196,721,000
Common shares outstanding at end of period (in shares)	203,377,000	145,073,000
Outstanding senior securities	$ 2,755,600	$ 2,060,400
Class I shares
Investment Company, Financial Highlights [Roll Forward]
Net asset value at beginning of period (in dollars per share)	$ 23.09	$ 23.56
Capital contribution (in dollars per share)	0	0
Net investment income (in dollars per share)	0.51	0.52
Net unrealized appreciation (depreciation) (in dollars per share)	(0.16)	0.01
Net realized gains (losses) (in dollars per share)	0.03	0.03
(Provision) benefit for taxes on realized and unrealized gains (losses) (in dollars per share)	0	0
Net increase (decrease) in net assets resulting from operations (in dollars per share)	0.38	0.56
Distributions of net investment income to shareholders (in dollars per share)	(0.51)	(0.52)
Distributions in excess of net investment income (in dollars per share)	(0.03)	(0.08)
Net asset value at end of period (in dollars per share)	$ 22.93	$ 23.52
Total return	1.67%	2.40%
Common shares outstanding at beginning of period (in shares)	139,709,000	89,884,000
Common shares outstanding at end of period (in shares)	145,699,000	97,207,000
Net assets at the beginning of the period	$ 3,225,643	$ 2,118,000
Net assets at end of period	3,341,128	2,286,444
Average net assets	$ 3,423,169	$ 2,245,265
Ratio of net investment income to average net assets	2.20%	2.22%
Ratio of total expenses to average net assets	1.65%	2.00%
Ratio of net expenses to average net assets	1.65%	2.00%
Ratio of portfolio turnover to average investments at fair value	3.93%	9.95%
Weighted average outstanding debt	$ 2,669,291	$ 1,965,163
Average debt per share (in dollars per share)	$ 12.87	$ 13.83
Asset coverage ratio	269.41%	265.13%
Class S shares
Investment Company, Financial Highlights [Roll Forward]
Net asset value at beginning of period (in dollars per share)	$ 23.09	$ 23.56
Capital contribution (in dollars per share)	0	0
Net investment income (in dollars per share)	0.46	0.47
Net unrealized appreciation (depreciation) (in dollars per share)	(0.16)	0.01
Net realized gains (losses) (in dollars per share)	0.03	0.03
(Provision) benefit for taxes on realized and unrealized gains (losses) (in dollars per share)	0	0
Net increase (decrease) in net assets resulting from operations (in dollars per share)	0.33	0.51
Distributions of net investment income to shareholders (in dollars per share)	(0.46)	(0.47)
Distributions in excess of net investment income (in dollars per share)	(0.03)	(0.08)
Net asset value at end of period (in dollars per share)	$ 22.93	$ 23.52
Total return	1.45%	2.18%
Common shares outstanding at beginning of period (in shares)	56,785,000	44,323,000
Common shares outstanding at end of period (in shares)	57,129,000	47,759,000
Net assets at the beginning of the period	$ 1,310,917	$ 1,044,424
Net assets at end of period	1,309,867	1,123,357
Average net assets	$ 1,351,855	$ 1,111,550
Ratio of net investment income to average net assets	1.99%	2.01%
Ratio of total expenses to average net assets	1.86%	2.18%
Ratio of net expenses to average net assets	1.86%	2.18%
Ratio of portfolio turnover to average investments at fair value	3.93%	9.95%
Weighted average outstanding debt	$ 2,669,291	$ 1,965,163
Average debt per share (in dollars per share)	$ 12.87	$ 13.83
Asset coverage ratio	269.41%	265.13%
Class D shares
Investment Company, Financial Highlights [Roll Forward]
Net asset value at beginning of period (in dollars per share)	$ 23.09	$ 23.56
Capital contribution (in dollars per share)	0	0
Net investment income (in dollars per share)	0.50	0.51
Net unrealized appreciation (depreciation) (in dollars per share)	(0.16)	0.01
Net realized gains (losses) (in dollars per share)	0.03	0.03
(Provision) benefit for taxes on realized and unrealized gains (losses) (in dollars per share)	0	0
Net increase (decrease) in net assets resulting from operations (in dollars per share)	0.37	0.55
Distributions of net investment income to shareholders (in dollars per share)	(0.50)	(0.51)
Distributions in excess of net investment income (in dollars per share)	(0.03)	(0.08)
Net asset value at end of period (in dollars per share)	$ 22.93	$ 23.52
Total return	1.61%	2.33%
Common shares outstanding at beginning of period (in shares)	174,000	81,000
Common shares outstanding at end of period (in shares)	407,000	107,000
Net assets at the beginning of the period	$ 4,028	$ 1,916
Net assets at end of period	9,321	2,515
Average net assets	$ 7,594	$ 2,380
Ratio of net investment income to average net assets	2.14%	2.16%
Ratio of total expenses to average net assets	1.71%	2.05%
Ratio of net expenses to average net assets	1.71%	2.05%
Ratio of portfolio turnover to average investments at fair value	3.93%	9.95%
Weighted average outstanding debt	$ 2,669,291	$ 1,965,163
Average debt per share (in dollars per share)	$ 12.87	$ 13.83
Asset coverage ratio	269.41%	265.13%
Class T shares
Investment Company, Financial Highlights [Roll Forward]
Net asset value at beginning of period (in dollars per share)	$ 23.09
Capital contribution (in dollars per share)	0
Net investment income (in dollars per share)	0.46
Net unrealized appreciation (depreciation) (in dollars per share)	(0.16)
Net realized gains (losses) (in dollars per share)	0.03
(Provision) benefit for taxes on realized and unrealized gains (losses) (in dollars per share)	0
Net increase (decrease) in net assets resulting from operations (in dollars per share)	0.33
Distributions of net investment income to shareholders (in dollars per share)	(0.46)
Distributions in excess of net investment income (in dollars per share)	(0.03)
Net asset value at end of period (in dollars per share)	$ 22.93	$ 0
Total return	1.45%
Common shares outstanding at beginning of period (in shares)	53,000
Common shares outstanding at end of period (in shares)	142,000
Net assets at the beginning of the period	$ 1,217
Net assets at end of period	3,247
Average net assets	$ 3,032
Ratio of net investment income to average net assets	1.99%
Ratio of total expenses to average net assets	1.86%
Ratio of net expenses to average net assets	1.86%
Ratio of portfolio turnover to average investments at fair value	3.93%
Weighted average outstanding debt	$ 2,669,291
Average debt per share (in dollars per share)	$ 12.87
Asset coverage ratio	269.41%