Investment in Loans (Schedule of 90 Days or More Past Due) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		$ 1,417,054	$ 1,387,733
Loans, at fair value	[1],[2]	1,453,480	1,412,426
Proceeds from the disposition of loans (non-cash)		113,791	0
Commercial mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		212,716	277,870
Loans, at fair value		213,031	274,759
Residential mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		1,150,303	911,705
Loans, at fair value		1,187,069	932,203
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		48,180	179,743
Loans, at fair value		47,525	186,954
Non-accrual status [Member] | Commercial mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, at fair value			10,700
Non-accrual status [Member] | Commercial mortgage loans | 90 Days or More Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		44,233	28,936
Loans, at fair value		44,052	26,545
Non-accrual status [Member] | Residential mortgage loans | 90 Days or More Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		64,509	22,092
Loans, at fair value		60,381	19,401
Non-accrual status [Member] | Consumer loans | 90 Days or More Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unpaid Principal Balance		1,015	5,633
Loans, at fair value		$ 930	$ 5,225

[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.