Debt - Narrative (Details)		1 Months Ended	12 Months Ended			119 Months Ended
		Aug. 31, 2022 USD ($)	Dec. 31, 2023 USD ($) securitization counterparty facility trust $ / shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 USD ($) securitization $ / shares	Jan. 01, 2022 USD ($)
Debt Instrument [Line Items]
Percentage of guarantors beneficial interest			100.00%			100.00%
Other prepaid collateral			$ 3,756,000	$ 5,152,000		$ 3,756,000
Number of securitizations completed | securitization						18
Number of securitizations outstanding | securitization			5			5
Convertible senior notes, net	[1]		$ 103,516,000	104,256,000		$ 103,516,000
Interest expense			59,286,000	43,632,000	$ 36,742,000
Purchase price of repurchased notes			952,000	75,000	$ 8,762,000
Additional paid-in capital			308,933,000	$ 335,328,000		308,933,000
Put liability			$ 16,600,000			$ 16,600,000
Accounting Standards Update 2020-06
Debt Instrument [Line Items]
Convertible senior notes, net							$ 700,000
Series A Preferred Stock
Debt Instrument [Line Items]
Preferred stock dividend rate percentage			7.25%	7.25%
Series B Preferred Stock
Debt Instrument [Line Items]
Preferred stock dividend rate percentage			5.00%	5.00%
Mortgage loans | Non-rated Secured Borrowings
Debt Instrument [Line Items]
Number of securitizations outstanding | securitization			1			1
Mortgage loans | Rated Secured Borrowings
Debt Instrument [Line Items]
Number of securitizations outstanding | securitization			4			4
Convertible Notes Payable
Debt Instrument [Line Items]
Interest Rate			7.25%			7.25%
Principal amount of note (in dollars per share) | $ / shares			$ 25.00
If-converted value in excess of principal			$ 65,300,000
Unamortized discount			0	$ 300,000		$ 0
Interest expense			10,600,000
Conversion discount (premium) - Convertible senior notes			$ 300,000	$ 800,000
Interest rate, effective percentage			7.25%	8.03%		7.25%
Repurchase amount			$ 1,000,000	$ 100,000		$ 1,000,000
Purchase price of repurchased notes			1,000,000	100,000
Amortization of debt discount (premium) and deferred expenses			$ 900,000
Senior Notes | 8.875% Senior Unsecured Notes Due September 2027
Debt Instrument [Line Items]
Interest Rate		8.875%
Interest rate, effective percentage			9.96%			9.96%
Aggregate principal		$ 110,000,000
Debt instrument term (in years)		5 years
Issuance amount, percent of par value (in percent)		0.99009
Proceeds from unsecured notes payable		$ 106,100,000
Put liability			$ 90,000,000			$ 90,000,000
Amount outstanding			110,000,000	110,000,000		110,000,000
Notes Payable, Other Payables
Debt Instrument [Line Items]
Debt issuance costs, net			$ (3,200,000)	$ (4,000,000)		$ (3,200,000)
Master Repurchase Agreement
Debt Instrument [Line Items]
Interest Rate			7.44%	6.31%		7.44%
Amount outstanding			$ 375,745,000	$ 445,855,000		$ 375,745,000
Master Repurchase Agreement | Delaware Trust | Mortgage loans
Debt Instrument [Line Items]
Number of facilities repurchased | facility			2
Number of wholly-owned Delaware trusts | trust			2
Number of counterparties | counterparty			2
Ceiling for each repurchase facility			$ 150,000,000			150,000,000
Master Repurchase Agreement | Delaware Trust | Mortgage loans | Minimum
Debt Instrument [Line Items]
Percentage of purchase price for each mortgage loan or REO			75.00%
Master Repurchase Agreement | Delaware Trust | Mortgage loans | Maximum
Debt Instrument [Line Items]
Percentage of purchase price for each mortgage loan or REO			90.00%
Master Repurchase Agreement | Delaware Trust | Mortgages One
Debt Instrument [Line Items]
Ceiling for each repurchase facility			$ 400,000,000			400,000,000
Master Repurchase Agreement | Delaware Trust | Bonds
Debt Instrument [Line Items]
Number of facilities repurchased | facility			4
Convertible Notes Payable
Debt Instrument [Line Items]
Unpaid principal balance			$ 103,500,000	104,500,000		$ 103,500,000
Interest expense			$ 7,500,000	$ 8,400,000
Common Stock | Convertible Notes Payable
Debt Instrument [Line Items]
Conversion ratio			1.7405
Conversion price (in dollars per share) | $ / shares			$ 14.36			$ 14.36
Additional paid-in capital | Accounting Standards Update 2020-06
Debt Instrument [Line Items]
Additional paid-in capital							$ (700,000)
Gregory Funding LLC | Master Repurchase Agreement | Mortgage loans | Reperforming Mortgage Loans On Real Estate
Debt Instrument [Line Items]
Servicing fees percentage			0.65%
Gregory Funding LLC | Master Repurchase Agreement | Mortgage loans | Residential NPLs
Debt Instrument [Line Items]
Servicing fees percentage			1.25%
2017-D | Great Ajax Corp
Debt Instrument [Line Items]
Ownership percentage by parent (in percent)			50.00%	50.00%		50.00%

[1] Secured borrowings, net are presented net of deferred issuance costs of $3.1 million at December 31, 2023 and $4.7 million at December 31, 2022. Convertible senior notes, net are presented net of deferred issuance costs of zero and $0.3 million at December 31, 2023 and 2022, respectively. Notes payable, net are presented net of deferred issuance costs and discount of $3.2 million at December 31, 2023 and $4.0 million at December 31, 2022.