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Fair Value Measurements - Fair Value Hierarchy of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	$ 9,626,202	$ 9,617,248
First lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	9,425,003	9,419,963
Second lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	46,678	46,336
Investments in equity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	154,521	150,949
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0	0
Level 1 | First lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0	0
Level 1 | Second lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0	0
Level 1 | Investments in equity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	199,713	144,452
Level 2 | First lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	199,713	144,452
Level 2 | Second lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0	0
Level 2 | Investments in equity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	9,426,489	9,472,796
Level 3 | First lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	9,225,290	9,275,511
Level 3 | Second lien debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	46,678	46,336
Level 3 | Investments in equity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total	$ 154,521	$ 150,949

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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