Asset-Backed Securities Issued - Accrued Interest Payable (Details) - Asset-backed securities issued - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total Accrued Interest Payable on ABS Issued	$ 25,684	$ 25,401
Legacy Sequoia
Debt Instrument [Line Items]
Total Accrued Interest Payable on ABS Issued	107	99
Sequoia
Debt Instrument [Line Items]
Total Accrued Interest Payable on ABS Issued	9,598	8,452
CAFL
Debt Instrument [Line Items]
Total Accrued Interest Payable on ABS Issued	10,342	11,030
Freddie Mac SLST
Debt Instrument [Line Items]
Total Accrued Interest Payable on ABS Issued	4,405	4,630
Freddie Mac K-Series
Debt Instrument [Line Items]
Total Accrued Interest Payable on ABS Issued	$ 1,232	$ 1,190