Related Party Transactions (Details)		3 Months Ended		9 Months Ended
		Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) period numberOfWarrants	Sep. 30, 2020 USD ($)		Dec. 31, 2020 USD ($)
Related Party Transaction [Line Items]
Annual base management fee percentage				1.50%
Base management fee to affiliate	[1]	$ 3,675,000	$ 2,981,000	$ 10,308,000	$ 8,330,000
Base management fee, gross		4,100,000	3,200,000	11,100,000	9,200,000
Management Fee Expense, Rebates		395,000	201,000	$ 784,000	853,000	[1]
Incentive fee rate				25.00%
Incentive Fee, Loss Carryforward		0		$ 0			$ 0
Incentive fee hurdle rate fixed				9.00%
Incentive fee hurdle rate floating				3.00%
Minimum percentage of incentive fee to be paid in share				10.00%
Termination Fee, Number Of Periods | period				2
Termination Fee, Period				12 months
Expense Reimbursement Period				60 days
Expense Reimbursement - Manager				$ 8,700,000	7,400,000
Real estate owned	[2],[3]	37,002,000		37,002,000			23,598,000
Investment in unconsolidated entities, at fair value	[2]	142,019,000		142,019,000			141,620,000
Securities, at fair value(1)(2)	[2],[3]	1,895,563,000		1,895,563,000			1,514,185,000
Non-controlling interests	[2]	31,944,000		31,944,000			36,357,000
Accrued expenses and other liabilities	[2]	20,943,000		20,943,000			18,659,000
Reverse repurchase agreements		2,105,836,000		2,105,836,000			1,496,931,000
Other assets	[2]	3,608,000		3,608,000			2,575,000
Unpaid Principal Balance		1,940,279,000		1,940,279,000			1,417,054,000
Related Party Transaction, Purchases from Related Party				5,500,000	1,600,000
Securities Collateral relating to Reverse Repurchase Agreements		2,400,000,000		2,400,000,000			1,800,000,000
Income Tax Expense (Benefit)		(2,009,000)	$ 2,494,000	3,149,000	3,490,000
Loans, at fair value	[2],[3]	1,996,529,000		1,996,529,000			1,453,480,000
Corporate loan [Member]
Related Party Transaction [Line Items]
Unpaid Principal Balance		16,828,000		16,828,000			5,855,000
Loans, at fair value		16,561,000		16,561,000			5,855,000
Commercial mortgage loans and REO
Related Party Transaction [Line Items]
Fair Value		34,000,000		34,000,000			34,000,000.0
Reverse repurchase agreements		134,900,000		134,900,000			116,100,000
Affiliated Entity [Member]
Related Party Transaction [Line Items]
Accounts payable and accrued expenses	[2]	3,000,000		3,000,000			2,500,000
Mortgage Originator
Related Party Transaction [Line Items]
Warehouse facility, monetary amount		$ 5,000,000		$ 5,000,000
Interest rate		15.00%		15.00%
Advances made under warehouse facility		$ 0		$ 0			0
Loans purchased under commitment agreement				$ 150,000,000
Number of warrants purchased under commitment agreement | numberOfWarrants				9,329,000
Mortgage Originator | Warrants
Related Party Transaction [Line Items]
Investment in unconsolidated entities, at fair value		6,300,000		$ 6,300,000			3,600,000
Related Party-Consumer Loans Titled in Name of Related Party
Related Party Transaction [Line Items]
Fair value of loans held in related party trust		71,100,000		71,100,000			44,500,000
Purchasing Entity
Related Party Transaction [Line Items]
Fair value of loans held in related party trust		54,500,000		54,500,000			45,100,000
Consumer loans purchased through affiliate				25,000,000	$ 84,700,000
Estimated remaining contingent purchase obligations		34,300,000		34,300,000			13,000,000
Related party trust - Residential Mortgage Loans and REO
Related Party Transaction [Line Items]
Fair value of loans held in related party trust		741,600,000		741,600,000			387,400,000
Related party mortgage originator (with flow mortgage loan purchase and sale agreement) [Member] | Non-Exchange Traded Equity Investment in Mortgage Originators [Member]
Related Party Transaction [Line Items]
Drawn down amount being guaranteed		$ 10,400,000		$ 10,400,000			5,300,000
Investment in Loan Originator | Corporate loan [Member]
Related Party Transaction [Line Items]
Investment Interest Rate		3.00%		3.00%
Unpaid Principal Balance		$ 3,000,000		$ 3,000,000
Lending Commitment				6,000,000
Loans, at fair value		3,000,000		3,000,000
Non-controlling interest of joint venture partner | Unrelated third party joint venture interest | Commercial mortgage loans and REO
Related Party Transaction [Line Items]
Non-controlling interests		2,000,000		2,000,000			4,100,000
Non-controlling interest of joint venture partner | Related party joint venture interest | Commercial mortgage loans and REO
Related Party Transaction [Line Items]
Non-controlling interests		3,600,000		3,600,000			8,900,000
Mortgage-related Commercial | Corporate equity securities
Related Party Transaction [Line Items]
Fair Value		23,300,000		23,300,000			33,900,000
Jepson Holdings Limited
Related Party Transaction [Line Items]
Investment in unconsolidated entities, at fair value		1,500,000		1,500,000			1,800,000
Loan receivable from affiliated entity related to warehouse facility
Related Party Transaction [Line Items]
Other assets		2,100,000		2,100,000			6,100,000
Participation in multi-borrower financing facility
Related Party Transaction [Line Items]
Outstanding debt of related party		$ 435,700,000		435,700,000			$ 192,300,000
Maximum | Mortgage Originator
Related Party Transaction [Line Items]
Commitment to purchase loans				$ 150,000,000
Number of warrants available for purchase under commitment agreement | numberOfWarrants				9,329,000

[1] See Note 13 for further details on management fee rebates.

[2] Ellington Financial Inc.'s Condensed 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.

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