Securitized Debt Obligations, Net - Schedule of Information on Securitized Debt Obligations (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
Debt Instrument [Line Items]
Interest expense on securitized debt obligations	$ 39,800	$ 87,600
Senior CLO Securities Outstanding
Debt Instrument [Line Items]
Count | loan	3	3
Principal Balance	$ 2,671,734	$ 2,673,541
Book Value	$ 2,664,208	$ 2,664,010
Senior CLO Securities Outstanding | 2021 FL4 Collateralized Loan Obligation
Debt Instrument [Line Items]
Count | loan	1	1
Principal Balance	$ 803,750	$ 803,750
Book Value	$ 800,192	$ 799,626
Senior CLO Securities Outstanding | 2020 FL3 Collateralized Loan Obligation
Debt Instrument [Line Items]
Count | loan	1	1
Principal Balance	$ 808,750	$ 808,750
Book Value	$ 807,428	$ 806,757
Senior CLO Securities Outstanding | 2020 FL2 Collateralized Loan Obligation
Debt Instrument [Line Items]
Count | loan	1	1
Principal Balance	$ 1,059,234	$ 1,061,041
Book Value	$ 1,056,588	$ 1,057,627
Underlying Collateral Assets
Debt Instrument [Line Items]
Count | loan	62	63
Principal Balance	$ 3,316,109	$ 3,317,916
Book Value	$ 3,316,109	$ 3,317,916
Underlying Collateral Assets | 2021 FL4 Collateralized Loan Obligation
Debt Instrument [Line Items]
Count | loan	29	30
Principal Balance	$ 1,000,000	$ 1,000,000
Book Value	$ 1,000,000	$ 1,000,000
Underlying Collateral Assets | 2020 FL3 Collateralized Loan Obligation
Debt Instrument [Line Items]
Count | loan	16	16
Principal Balance	$ 1,000,000	$ 1,000,000
Book Value	$ 1,000,000	$ 1,000,000
Underlying Collateral Assets | 2020 FL2 Collateralized Loan Obligation
Debt Instrument [Line Items]
Count | loan	17	17
Principal Balance	$ 1,316,109	$ 1,317,916
Book Value	$ 1,316,109	$ 1,317,916
LIBOR
Debt Instrument [Line Items]
One-month USD LIBOR	4.86%	4.39%
LIBOR | Senior CLO Securities Outstanding
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	1.74%	1.73%
LIBOR | Senior CLO Securities Outstanding | 2021 FL4 Collateralized Loan Obligation
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	1.57%	1.57%
LIBOR | Senior CLO Securities Outstanding | 2020 FL3 Collateralized Loan Obligation
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	2.15%	2.14%
LIBOR | Senior CLO Securities Outstanding | 2020 FL2 Collateralized Loan Obligation
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	1.55%	1.55%
LIBOR | Underlying Collateral Assets
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	3.39%	3.38%
LIBOR | Underlying Collateral Assets | 2021 FL4 Collateralized Loan Obligation
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	3.51%	3.47%
LIBOR | Underlying Collateral Assets | 2020 FL3 Collateralized Loan Obligation
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	3.24%	3.25%
LIBOR | Underlying Collateral Assets | 2020 FL2 Collateralized Loan Obligation
Debt Instrument [Line Items]
Wtd. Avg. Yield/Cost	3.41%	3.42%
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
30 day average compounded SOFR reference rate	4.80%	4.36%