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Borrowings - Holdings Credit Facility (Details) - USD ($) $ in Thousands		7 Months Ended	12 Months Ended					24 Months Ended
	Apr. 28, 2023	Apr. 19, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 27, 2023	Oct. 26, 2023	Jun. 09, 2018	Jun. 08, 2018	Nov. 05, 2014
Line of Credit Facility [Line Items]
Minimum asset coverage ratio										150.00%	200.00%	150.00%
Amortization of financing costs			$ 6,780	$ 6,837	$ 7,388
Holdings Credit Facility
Line of Credit Facility [Line Items]
Credit facility outstanding balance			515,063	618,963	545,263
Revolving Credit Facility | Holdings Credit Facility | Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity									$ 800
Available borrowing capacity			$ 730,000
Borrowing capacity, first percentage			35.00%
Borrowing capacity, second percentage			45.00%
Borrowing capacity, third percentage			55.00%
Borrowing capacity, fourth percentage			67.50%
Borrowing capacity, fifth percentage			70.00%
Minimum asset coverage ratio			150.00%
Interest expense			$ 41,176	22,542	10,210
Non-usage fee			760	743	1,282
Amortization of financing costs			$ 1,912	$ 2,956	$ 2,852
Weighted average interest rate			7.00%	3.90%	2.10%
Effective interest rate			7.60%	4.50%	3.00%
Average debt outstanding			$ 577,759	$ 581,367	$ 478,016	$ 526,645	$ 598,129
Revolving Credit Facility | Holdings Credit Facility, Broadly Syndicated Loans | Credit Facility | SOFR
Line of Credit Facility [Line Items]
Interest rate margin	1.70%
Revolving Credit Facility | Holdings Credit Facility, Broadly Syndicated Loans | Credit Facility | LIBOR
Line of Credit Facility [Line Items]
Interest rate margin		2.00%						1.60%
Revolving Credit Facility | Holdings Credit Facility, Excluding Broadly Syndicated Loans | Credit Facility | SOFR
Line of Credit Facility [Line Items]
Interest rate margin	2.20%							2.50%
Revolving Credit Facility | Holdings Credit Facility, Excluding Broadly Syndicated Loans | Credit Facility | LIBOR
Line of Credit Facility [Line Items]
Interest rate margin		2.50%						2.10%

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of the fee for available but unused credit capacity under the credit facility.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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