Mortgage Loans - Schedule of carrying value of mortgage loans (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	$ 368,288	$ 55,718
Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	438,698	864,551
GAOP - 7f7 >50 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	368,288	55,718
GAOP - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	9,625	313,803
GAOP 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	1,196	37,152
GAOP - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	7,757	87,314
Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	360,799	364,821
Great AJAX REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	31,520	31,611
Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	27,801	29,850
Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	360,799	364,821
Great Ajax II REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	31,520	31,611
Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	27,801	29,850
Current | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	194,244	1,284
Current | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	342,657	558,780
Current | GAOP - 7f7 >50 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	194,244	1,284
Current | GAOP - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	6,232	199,229
Current | GAOP 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	756	20,514
Current | GAOP - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	1,186	8,565
Current | Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	303,408	300,506
Current | Great AJAX REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	25,629	25,592
Current | Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	5,446	4,374
30 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	46,815	592
30 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	37,190	106,557
30 | GAOP - 7f7 >50 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	46,815	592
30 | GAOP - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	2,535	49,868
30 | GAOP 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	45	7,516
30 | GAOP - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	410	6,906
30 | Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	29,605	36,277
30 | Great AJAX REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	2,726	3,846
30 | Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	1,869	2,144
60 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	37,453	0
60 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	17,532	1,625
60 | GAOP - 7f7 >50 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	37,453	0
60 | GAOP - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	16	283
60 | GAOP 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	114	78
60 | GAOP - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	0	421
60 | Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	11,775	801
60 | Great AJAX REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	1,252	42
60 | Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	4,375	0
90 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	70,193	26,243
90 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	30,876	161,119
90 | GAOP - 7f7 >50 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	70,193	26,243
90 | GAOP - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	842	63,498
90 | GAOP 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	281	9,044
90 | GAOP - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	2,293	45,058
90 | Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	15,606	26,600
90 | Great AJAX REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	1,913	2,131
90 | Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	9,941	14,788
Foreclosure | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	19,583	27,599
Foreclosure | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	10,443	36,470
Foreclosure | GAOP - 7f7 >50 | Mortgage loans held-for-sale, net
Mortgage Loans on Real Estate
Total	19,583	27,599
Foreclosure | GAOP - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	0	925
Foreclosure | GAOP 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	0	0
Foreclosure | GAOP - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	3,868	26,364
Foreclosure | Great Ajax II REIT - 7f7 >50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	405	637
Foreclosure | Great AJAX REIT 7f7 Less Than 50 | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	0	0
Foreclosure | Great Ajax II REIT - 6f6 and below | Mortgage loans held-for-investment, net
Mortgage Loans on Real Estate
Total	$ 6,170	$ 8,544