Debt - Summary of the Company's Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Debt	$ 1,329,677	$ 1,355,359
Unamortized debt issuance costs	(8,215)	(9,512)
Net debt	1,321,462	1,345,847
Unused amount of revolving credit facilities (subject to borrowing base)	580,655	555,117
Senior Revolving Credit Facility
Debt Instrument [Line Items]
Debt	105,315	147,547
Unamortized debt issuance costs	(1,201)	(1,104)
Net debt	104,114	146,443
RMR II revolving warehouse credit facility
Debt Instrument [Line Items]
Debt		189
Unamortized debt issuance costs		(900)
Net debt		189
RMR IV revolving warehouse credit facility
Debt Instrument [Line Items]
Debt	65	18,144
Unamortized debt issuance costs	(400)	(338)
Net debt	65	17,806
RMR V revolving warehouse credit facility
Debt Instrument [Line Items]
Debt	20,099	286
Unamortized debt issuance costs	(400)	(400)
Net debt	20,099	286
RMR VI revolving warehouse credit facility
Debt Instrument [Line Items]
Debt	15,005
Unamortized debt issuance costs	(900)
Net debt	15,005
RMIT 2020-1 securitization
Debt Instrument [Line Items]
Debt	180,214	180,214
Unamortized debt issuance costs	(412)	(618)
Net debt	179,802	179,596
RMIT 2021-1 securitization
Debt Instrument [Line Items]
Debt	248,916	248,916
Unamortized debt issuance costs	(774)	(985)
Net debt	248,142	247,931
RMIT 2021-2 securitization
Debt Instrument [Line Items]
Debt	200,192	200,192
Unamortized debt issuance costs	(1,427)	(1,534)
Net debt	198,765	198,658
RMIT 2021-3 securitization
Debt Instrument [Line Items]
Debt	125,202	125,202
Unamortized debt issuance costs	(1,099)	(1,178)
Net debt	124,103	124,024
RMIT 2022-1 securitization
Debt Instrument [Line Items]
Debt	250,374	250,374
Unamortized debt issuance costs	(1,629)	(1,841)
Net debt	248,745	248,533
RMIT 2022-2B securitization
Debt Instrument [Line Items]
Debt	184,295	184,295
Unamortized debt issuance costs	(1,673)	(1,914)
Net debt	$ 182,622	$ 182,381

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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