Mortgage Loans - Schedule of carrying value of mortgage loans (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Mortgage Loans on Real Estate
Total	$ 961,277	$ 989,084
GAOP - 7f7 >50
Mortgage Loans on Real Estate
Total	329,548	330,796
GAOP 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	43,686	48,649
GAOP - 6f6 and below
Mortgage Loans on Real Estate
Total	147,112	151,808
Great Ajax II REIT - 7f7 >50
Mortgage Loans on Real Estate
Total	372,179	378,281
Great AJAX REIT 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	36,037	39,825
Great Ajax II REIT - 6f6 and below
Mortgage Loans on Real Estate
Total	32,715	39,725
Current
Mortgage Loans on Real Estate
Total	695,255	580,610
Current | GAOP - 7f7 >50
Mortgage Loans on Real Estate
Total	263,192	198,006
Current | GAOP 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	33,184	26,303
Current | GAOP - 6f6 and below
Mortgage Loans on Real Estate
Total	9,472	3,333
Current | Great Ajax II REIT - 7f7 >50
Mortgage Loans on Real Estate
Total	355,105	319,677
Current | Great AJAX REIT 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	34,131	33,113
Current | Great Ajax II REIT - 6f6 and below
Mortgage Loans on Real Estate
Total	171	178
30
Mortgage Loans on Real Estate
Total	59,283	95,475
30 | GAOP - 7f7 >50
Mortgage Loans on Real Estate
Total	22,041	44,773
30 | GAOP 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	3,925	5,815
30 | GAOP - 6f6 and below
Mortgage Loans on Real Estate
Total	14,137	1,538
30 | Great Ajax II REIT - 7f7 >50
Mortgage Loans on Real Estate
Total	11,673	39,161
30 | Great AJAX REIT 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	1,523	4,188
30 | Great Ajax II REIT - 6f6 and below
Mortgage Loans on Real Estate
Total	5,984	0
60
Mortgage Loans on Real Estate
Total	36,740	1,835
60 | GAOP - 7f7 >50
Mortgage Loans on Real Estate
Total	10,721	772
60 | GAOP 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	1,010	140
60 | GAOP - 6f6 and below
Mortgage Loans on Real Estate
Total	17,037	94
60 | Great Ajax II REIT - 7f7 >50
Mortgage Loans on Real Estate
Total	2,494	700
60 | Great AJAX REIT 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	237	90
60 | Great Ajax II REIT - 6f6 and below
Mortgage Loans on Real Estate
Total	5,241	39
90
Mortgage Loans on Real Estate
Total	106,055	254,108
90 | GAOP - 7f7 >50
Mortgage Loans on Real Estate
Total	32,141	86,603
90 | GAOP 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	5,446	16,232
90 | GAOP - 6f6 and below
Mortgage Loans on Real Estate
Total	51,672	94,010
90 | Great Ajax II REIT - 7f7 >50
Mortgage Loans on Real Estate
Total	2,603	18,743
90 | Great AJAX REIT 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	146	2,434
90 | Great Ajax II REIT - 6f6 and below
Mortgage Loans on Real Estate
Total	14,047	36,086
Foreclosure
Mortgage Loans on Real Estate
Total	63,944	57,056
Foreclosure | GAOP - 7f7 >50
Mortgage Loans on Real Estate
Total	1,453	642
Foreclosure | GAOP 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	121	159
Foreclosure | GAOP - 6f6 and below
Mortgage Loans on Real Estate
Total	54,794	52,833
Foreclosure | Great Ajax II REIT - 7f7 >50
Mortgage Loans on Real Estate
Total	304	0
Foreclosure | Great AJAX REIT 7f7 Less Than 50
Mortgage Loans on Real Estate
Total	0	0
Foreclosure | Great Ajax II REIT - 6f6 and below
Mortgage Loans on Real Estate
Total	$ 7,272	$ 3,422