Joint Venture - Selected Statement of Operations Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenues [Abstract]
Total investment income	$ 6,694,692	$ 5,738,009	$ 3,602,347
Expenses:
Interest expense	1,838,600	1,759,437	990,538
Total expenses before tax expense	2,952,489	2,646,721	1,616,795
Net investment income before tax expense	3,742,203	3,091,288	1,985,552
Tax expense	33,724	32,826	975
Net investment income after tax expense	3,708,479	3,058,462	1,984,577
Net realized and change in unrealized gain (loss):
Net change in unrealized gain (loss) on investments	(97,287)	615,705	(1,045,678)
Net realized gain (loss) on investments	(126,664)	(310,984)	(275,829)
Net realized and change in unrealized gain (loss)	(223,951)	304,721	(1,321,507)
Net increase (decrease) in net assets resulting from operations	3,484,528	3,363,183	663,070
Non-controlled/non-affiliated investments
Revenues [Abstract]
Interest income	6,008,101	5,196,090	3,330,329
Payment-in-kind interest income	370,198	218,469	129,475
Dividend income	1,387	198	2,152
Nonconsolidated Investee | BCRED Emerald JV LP
Revenues [Abstract]
Total investment income	529,984	660,299	249,960
Expenses:
Interest expense	179,969	237,692	79,232
Other Expenses	2,316	4,115	3,914
Total expenses before tax expense	182,285	241,807	83,146
Net investment income before tax expense	347,699	418,492	166,814
Tax expense	0	0	0
Net investment income after tax expense	347,699	418,492	166,814
Net realized and change in unrealized gain (loss):
Net change in unrealized gain (loss) on investments	(76,545)	75,379	(82,456)
Net realized gain (loss) on investments	774	(9,491)	(6,965)
Net realized and change in unrealized gain (loss)	(75,771)	65,888	(89,421)
Net increase (decrease) in net assets resulting from operations	271,928	484,380	77,393
Nonconsolidated Investee | BCRED Verdelite JV LP
Revenues [Abstract]
Total investment income	61,391	44,544	5,610
Expenses:
Interest expense	37,436	23,370	2,936
Other Expenses	226	700	134
Total expenses before tax expense	37,662	24,070	3,070
Net investment income before tax expense	23,729	20,474	2,540
Tax expense	0	0	0
Net investment income after tax expense	23,729	20,474	2,540
Net realized and change in unrealized gain (loss):
Net change in unrealized gain (loss) on investments	(4,637)	14,145	(4,857)
Net realized gain (loss) on investments	926	2,218	0
Net realized and change in unrealized gain (loss)	(3,711)	16,363	(4,857)
Net increase (decrease) in net assets resulting from operations	20,018	36,837	(2,317)
Nonconsolidated Investee | Non-controlled/non-affiliated investments | BCRED Emerald JV LP
Revenues [Abstract]
Interest income	518,499	652,708	242,406
Payment-in-kind interest income	10,788	5,692	2,586
Dividend income	19	59	2,031
Other Income	678	1,840	2,937
Nonconsolidated Investee | Non-controlled/non-affiliated investments | BCRED Verdelite JV LP
Revenues [Abstract]
Interest income	61,366	44,353	5,607
Other Income	$ 25	$ 191	$ 3