Investment in Securities (Maturities of Securities) (Details) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)	[1],[2]	$ 2,087,360	$ 1,514,185
Amortized Cost		$ 1,975,520	$ 1,474,155
Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.52%	3.92%
Long
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 2,087,360	$ 1,514,185
Amortized Cost		$ 2,095,765	$ 1,508,997
Long | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.37%	3.84%
Long | Agency RMBS
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 1,663,328	$ 911,787
Amortized Cost		$ 1,671,020	$ 881,270
Long | Agency RMBS | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		2.95%	3.84%
Long | Agency RMBS | Less than three years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 45,956	$ 139,059
Amortized Cost		$ 45,678	$ 135,844
Long | Agency RMBS | Less than three years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.99%	4.15%
Long | Agency RMBS | Greater than three years less than seven years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 950,723	$ 770,173
Amortized Cost		$ 955,157	$ 742,946
Long | Agency RMBS | Greater than three years less than seven years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.24%	3.79%
Long | Agency RMBS | Greater than seven years less than eleven [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 665,617	$ 2,555
Amortized Cost		$ 669,147	$ 2,480
Long | Agency RMBS | Greater than seven years less than eleven [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		2.46%	3.01%
Long | Agency RMBS | Greater than eleven year [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 1,032	$ 0
Amortized Cost		$ 1,038	$ 0
Long | Agency RMBS | Greater than eleven year [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		1.99%	0.00%
Long | Agency RMBS | Interest only securities
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 33,288	$ 47,656
Amortized Cost		$ 32,607	$ 43,406
Long | Agency RMBS | Interest only securities | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.46%	3.36%
Long | Agency RMBS | Interest only securities | Less than three years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 8,981	$ 8,143
Amortized Cost		$ 8,466	$ 7,314
Long | Agency RMBS | Interest only securities | Less than three years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.10%	3.99%
Long | Agency RMBS | Interest only securities | Greater than three years less than seven years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 22,497	$ 32,669
Amortized Cost		$ 22,379	$ 29,362
Long | Agency RMBS | Interest only securities | Greater than three years less than seven years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.76%	3.74%
Long | Agency RMBS | Interest only securities | Greater than seven years less than eleven [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 1,810	$ 5,165
Amortized Cost		$ 1,762	$ 5,063
Long | Agency RMBS | Interest only securities | Greater than seven years less than eleven [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		1.46%	1.04%
Long | Agency RMBS | Interest only securities | Greater than eleven year [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 0	$ 1,679
Amortized Cost		$ 0	$ 1,667
Long | Agency RMBS | Interest only securities | Greater than eleven year [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.00%	0.83%
Long | Non-Agency RMBS and CMBS
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 224,485	$ 312,157
Amortized Cost		$ 220,050	$ 317,081
Long | Non-Agency RMBS and CMBS | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		4.03%	2.98%
Long | Non-Agency RMBS and CMBS | Less than three years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 96,277	$ 58,350
Amortized Cost		$ 92,396	$ 54,339
Long | Non-Agency RMBS and CMBS | Less than three years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		4.31%	3.39%
Long | Non-Agency RMBS and CMBS | Greater than three years less than seven years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 93,787	$ 114,815
Amortized Cost		$ 90,822	$ 109,161
Long | Non-Agency RMBS and CMBS | Greater than three years less than seven years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		4.79%	3.45%
Long | Non-Agency RMBS and CMBS | Greater than seven years less than eleven [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 26,639	$ 109,519
Amortized Cost		$ 28,293	$ 123,782
Long | Non-Agency RMBS and CMBS | Greater than seven years less than eleven [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		1.80%	2.74%
Long | Non-Agency RMBS and CMBS | Greater than eleven year [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 7,782	$ 29,473
Amortized Cost		$ 8,539	$ 29,799
Long | Non-Agency RMBS and CMBS | Greater than eleven year [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.34%	1.46%
Long | Non-Agency RMBS
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 201,605	$ 201,090
Amortized Cost		$ 196,747	$ 190,759
Long | Non-Agency RMBS | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		4.17%	3.15%
Long | Non-Agency RMBS | Interest only securities
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 17,712	$ 9,610
Amortized Cost		$ 16,701	$ 8,123
Long | Non-Agency RMBS | Interest only securities | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.64%	1.17%
Long | Non-Agency RMBS | Interest only securities | Less than three years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 6,360	$ 5,163
Amortized Cost		$ 5,504	$ 3,754
Long | Non-Agency RMBS | Interest only securities | Less than three years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.85%	0.92%
Long | Non-Agency RMBS | Interest only securities | Greater than three years less than seven years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 2,187	$ 4,447
Amortized Cost		$ 2,141	$ 4,369
Long | Non-Agency RMBS | Interest only securities | Greater than three years less than seven years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.12%	1.37%
Long | Non-Agency RMBS | Interest only securities | Greater than seven years less than eleven [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 9,165	$ 0
Amortized Cost		$ 9,056	$ 0
Long | Non-Agency RMBS | Interest only securities | Greater than seven years less than eleven [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.63%	0.00%
Long | Non-Agency RMBS | Interest only securities | Greater than eleven year [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 0	$ 0
Amortized Cost		$ 0	$ 0
Long | Non-Agency RMBS | Interest only securities | Greater than eleven year [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.00%	0.00%
Long | CLOs And Other Securities [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 140,991	$ 231,385
Amortized Cost		$ 149,599	$ 257,513
Long | CLOs And Other Securities [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		7.55%	5.09%
Long | CLOs And Other Securities [Member] | Less than three years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 110,953	$ 89,235
Amortized Cost		$ 114,392	$ 90,869
Long | CLOs And Other Securities [Member] | Less than three years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		8.82%	7.73%
Long | CLOs And Other Securities [Member] | Greater than three years less than seven years [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 30,038	$ 139,830
Amortized Cost		$ 35,207	$ 163,670
Long | CLOs And Other Securities [Member] | Greater than three years less than seven years [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		3.42%	3.69%
Long | CLOs And Other Securities [Member] | Greater than seven years less than eleven [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 0	$ 2,320
Amortized Cost		$ 0	$ 2,974
Long | CLOs And Other Securities [Member] | Greater than seven years less than eleven [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.00%	1.14%
Long | CLOs And Other Securities [Member] | Greater than eleven year [Member]
Securities, Available-for-sale [Line Items]
Securities, at fair value(1)(2)		$ 0	$ 0
Amortized Cost		$ 0	$ 0
Long | CLOs And Other Securities [Member] | Greater than eleven year [Member] | Weighted Average
Securities, Available-for-sale [Line Items]
Weighted Average Coupon		0.00%	0.00%

[1] Ellington Financial Inc.'s Consolidated Balance Sheet includes assets and liabilities of variable interest entities it has consolidated. See Note 9 for additional details on Ellington Financial Inc.'s consolidated variable interest entities.

[2] Includes assets pledged as collateral to counterparties. See Note 11 for additional details on the Company's borrowings and related collateral.