ARMOUR Residential REIT (ARR) 10-K 17 Feb 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 16, 2021	Jun. 30, 2020
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-34766
Entity Registrant Name	ARMOUR RESIDENTIAL REIT, INC.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	26-1908763
Entity Address, Address Line One	3001 Ocean Drive, Suite 201
Entity Address, City or Town	Vero Beach
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	32963
City Area Code	772
Local Phone Number	617-4340
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 597,492,827
Entity Common Stock, Shares Outstanding (in shares)		65,290,733
Documents Incorporated by Reference	Certain portions of the registrant’s definitive proxy statement pursuant to Regulation 14A of the Securities Exchange Act of 1934 for its 2021 annual meeting of stockholders are incorporated by reference into Part III of this Form 10-K.
Entity Central Index Key	0001428205
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false
Series C Preferred Stock
Entity Information [Line Items]
Title of 12(b) Security	Preferred Stock, 7.00% Series C Cumulative Redeemable
Trading Symbol	ARR-PRC
Security Exchange Name	NYSE
Common Stock
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	ARR
Security Exchange Name	NYSE

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash	$ 167,671	$ 181,395
Cash collateral posted to counterparties	3,997	91,771
Agency Securities (including pledged securities of $4,726,584 at December 31, 2020 and $11,188,502 at December 31, 2019)	5,178,322	11,941,766
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)	3,207,420	883,601
Derivatives, at fair value	54,686	24,751
Accrued interest receivable	12,833	35,085
Prepaid and other	1,977	9,051
Subordinated loan to BUCKLER	105,000	105,000
Total Assets	5,524,486	13,272,420
Liabilities:
Repurchase agreements	4,536,065	11,354,547
Cash collateral posted by counterparties	44,704	14,958
Payable for unsettled purchases	0	358,712
Derivatives, at fair value	1,217	71,974
Accrued interest payable- repurchase agreements	1,625	31,932
Accounts payable and other accrued expenses	2,571	3,590
Total Liabilities	4,586,182	11,835,713
Commitments and contingencies (Note 9)
Preferred stock, $0.001 par value, 50,000 shares authorized;
Common stock, $0.001 par value, 125,000 shares authorized, 65,290 and 58,877 shares issued and outstanding at December 31, 2020 and December 31, 2019	65	59
Additional paid-in capital	3,033,025	3,054,604
Accumulated deficit	(2,273,822)	(1,973,437)
Accumulated other comprehensive income	179,031	355,473
Total Stockholders’ Equity	938,304	1,436,707
Total Liabilities and Stockholders’ Equity	5,524,486	13,272,420
Credit Risk and Non-Agency Securities
Assets
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)	0	883,601
Series B Preferred Stock
Preferred stock, $0.001 par value, 50,000 shares authorized;
Preferred stock	0	8
Series C Preferred Stock
Preferred stock, $0.001 par value, 50,000 shares authorized;
Preferred stock	$ 5	$ 0

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Agency securities pledged	$ 11,188,502	$ 4,726,584
Credit risk and non-agency securities pledged		$ 810,549
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	125,000,000	125,000,000
Common stock, shares issued (in shares)	65,290,000	58,877,000
Common stock, shares outstanding (in shares)	65,290,000	58,877,000
Series B Preferred Stock
Preferred stock, par value (in dollars per share)		$ 0.001
Preferred stock, dividend rate	7.875%	7.875%
Preferred stock, shares issued (in shares)		8,383,000
Preferred stock, shares outstanding (in shares)		8,383,000
Preferred stock, aggregate liquidation preference		$ 209,583
Series C Preferred Stock
Preferred stock, par value (in dollars per share)	$ 0.001
Preferred stock, dividend rate	7.00%	7.00%
Preferred stock, shares issued (in shares)	5,347,000
Preferred stock, shares outstanding (in shares)	5,347,000
Preferred stock, aggregate liquidation preference	$ 133,675

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Interest Income:
Agency Securities, net of amortization of premium and fees	$ 22,594,000	$ 151,206,000		$ 382,811,000		$ 218,391,000
Total Interest Income		169,754,000		439,565,000		283,148,000
Interest expense- repurchase agreements	(3,076,000)	(62,939,000)		(288,229,000)		(154,230,000)
Interest expense- U.S. Treasury Securities sold short	0	(32,000)		0		0
Net Interest Income	19,540,000	106,783,000		151,336,000		128,918,000
Other Loss:
Realized gain (loss) on sale of available for sale Agency Securities (reclassified from Other comprehensive income (loss))	5,076,000	143,877,000		9,611,000		(152,950,000)
Credit loss expense	0	(1,012,000)		0		(12,090,000)
Gain on Agency Securities, trading	(503,000)	19,557,000		0		0
Loss on short sale of U.S. Treasury Securities	0	(414,000)		0		0
Subtotal		(5,776,000)		(12,638,000)		(199,678,000)
Realized loss on derivatives	16,641,000	(378,208,000)	[1]	(213,996,000)	[1]	(47,497,000)	[1]
Unrealized gain (loss) on derivatives	47,751,000	94,055,000		(136,127,000)		49,316,000
Subtotal		(284,153,000)		(350,123,000)		1,819,000
Total Other Loss		(289,929,000)		(362,761,000)		(197,859,000)
Expenses:
Management fees		29,628,000		29,571,000		27,246,000
Professional fees		3,770,000		2,808,000		4,978,000
Insurance		742,000		713,000		660,000
Compensation		5,597,000		3,889,000		3,774,000
Other		1,084,000		1,499,000		367,000
Total Expenses	10,046,000	40,821,000		38,480,000		37,025,000
Less management fees waived	(2,955,000)	(8,855,000)		0		0
Total Expenses after fees waived		31,966,000		38,480,000		37,025,000
Net Loss	81,413,000	(215,112,000)		(249,905,000)		(105,966,000)
Dividends on preferred stock	(2,320,000)	(9,787,000)		(15,634,000)		(17,032,000)
Net Loss related to common stockholders	$ 79,093,000	$ (224,899,000)		$ (265,539,000)		$ (122,998,000)
Net Loss per share related to common stockholders (Note 12):
Basic (in dollars per share)	$ 1.22	$ (3.57)		$ (4.59)		$ (2.92)
Diluted (in dollars per share)	1.21	(3.57)		(4.59)		(2.92)
Dividends declared per common share (in dollars per share)	$ 0.30	$ 1.20		$ 2.16		$ 2.28
Weighted average common shares outstanding:
Basic (in shares)	64,895	63,070		57,833		42,128
Diluted (in shares)	65,392	63,070		57,833		42,128
Credit Risk and Non-Agency Securities
Interest Income:
Debt securities, trading	$ 0	$ 17,746,000		$ 52,919,000		$ 56,427,000
Other Loss:
Debt securities, trading	(1,000)	(189,555,000)		(24,396,000)		(27,266,000)
Interest Only Securities
Interest Income:
Debt securities, trading		0		596,000		1,667,000
Other Loss:
Debt securities, trading		0		123,000		(1,007,000)
US Treasury Securities
Interest Income:
Debt securities, trading	0	469,000		1,353,000		4,644,000
Other Loss:
Debt securities, trading	0	21,771,000		2,024,000		(6,365,000)
Corporate Debt Securities
Interest Income:
Debt securities, trading	$ 22,000	$ 333,000		$ 1,886,000		$ 2,019,000
[1]	Interest expense related to our interest rate swap contracts is recorded as realized loss on derivatives on the consolidated statements of operations. For additional information, see Note 8 to the consolidated financial statements.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net Loss	$ (215,112)	$ (249,905)	$ (105,966)
Other comprehensive income (loss):
Reclassification adjustment for realized (gain) loss on sale of available for sale Agency Securities	(143,877)	(9,611)	152,950
Reclassification adjustment for credit loss expense on available for sale Agency Securities	1,012	0	12,090
Net unrealized gain (loss) on available for sale Agency Securities	(33,577)	408,954	(188,799)
Other comprehensive income (loss)	(176,442)	399,343	(23,759)
Comprehensive Income (Loss)	$ (391,554)	$ 149,438	$ (129,725)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjusted Balance	Series A Preferred Stock	Series B Preferred Stock	Series C Preferred Stock	Preferred StockSeries A Preferred Stock	Preferred StockSeries A Preferred StockCumulative Effect, Period of Adoption, Adjusted Balance	Preferred StockSeries B Preferred Stock	Preferred StockSeries B Preferred StockCumulative Effect, Period of Adoption, Adjusted Balance	Preferred StockSeries C Preferred Stock	Preferred StockSeries C Preferred StockCumulative Effect, Period of Adoption, Adjusted Balance	Common Stock	Common StockCumulative Effect, Period of Adoption, Adjusted Balance	Total Additional Paid-in Capital	Total Additional Paid-in CapitalCumulative Effect, Period of Adoption, Adjustment	Total Additional Paid-in CapitalCumulative Effect, Period of Adoption, Adjusted Balance	Total Additional Paid-in CapitalSeries A Preferred Stock	Total Additional Paid-in CapitalSeries B Preferred Stock	Total Additional Paid-in CapitalSeries C Preferred Stock	Accumulated Deficit	Accumulated DeficitCumulative Effect, Period of Adoption, Adjustment	Accumulated DeficitCumulative Effect, Period of Adoption, Adjusted Balance	Accumulated DeficitSeries A Preferred Stock	Accumulated DeficitSeries B Preferred Stock	Accumulated DeficitSeries C Preferred Stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss)Cumulative Effect, Period of Adoption, Adjusted Balance
Beginning balance (in shares) at Dec. 31, 2017						2,181		6,262		0		41,877
Beginning balance at Dec. 31, 2017	$ 1,326,051					$ 2		$ 6		$ 0		$ 42		$ 2,709,335						$ (1,363,223)						$ (20,111)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred dividends			$ (4,498)	$ (12,534)																			$ (4,498)	$ (12,534)
Common stock dividends	(97,024)																			(97,024)
Issuance of Preferred stock, net (in shares)								107				840
Issuance of Preferred stock, net of expenses				2,632								$ 19,001						$ 2,632
Issuance of common stock, net (in shares)												1,723
Issuance of common stock, net	38,014											$ 2		38,012
Stock based compensation, net of withholding requirements (in shares)												102
Stock based compensation, net of withholding requirements	2,397													2,397
Net Loss	(105,966)																			(105,966)
Other comprehensive income (loss)	(23,759)																									(23,759)
Ending balance (in shares) at Dec. 31, 2018						2,181	2,181	6,369	6,369	0	0	43,702	43,702
Ending balance at Dec. 31, 2018	1,125,313	$ 1,125,313				$ 2	$ 2	$ 6	$ 6	$ 0	$ 0	$ 44	$ 44	2,752,376	$ 176	$ 2,752,552				(1,583,245)	$ (176)	$ (1,583,421)				(43,870)	$ (43,870)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred dividends			(2,249)	(13,385)																			$ (2,249)	(13,385)
Common stock dividends	(124,477)																			(124,477)
Preferred stock, called for redemption (in shares)						(2,181)
Preferred stock, called for redemption			$ (54,514)			$ (2)											$ (54,512)
Issuance of Preferred stock, net (in shares)								2,014
Issuance of Preferred stock, net of expenses				49,795				$ 2										49,793
Issuance of common stock, net (in shares)												16,064
Issuance of common stock, net	321,860											$ 16		321,844
Stock based compensation, net of withholding requirements (in shares)												111
Stock based compensation, net of withholding requirements	2,694													2,694
Common stock repurchased (in shares)												(1,000)
Common stock repurchased, net	(17,768)											$ (1)		(17,767)
Net Loss	(249,905)																			(249,905)
Other comprehensive income (loss)	399,343																									399,343
Ending balance (in shares) at Dec. 31, 2019						0		8,383		0		58,877
Ending balance at Dec. 31, 2019	1,436,707					$ 0		$ 8		$ 0		$ 59		3,054,604						(1,973,437)						355,473
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred dividends				(1,375)	$ (8,412)																			$ (1,375)	$ (8,412)
Common stock dividends	(75,486)																			(75,486)
Preferred stock, called for redemption (in shares)								(8,383)
Preferred stock, called for redemption				$ (209,583)				$ (8)										$ (209,575)
Issuance of Preferred stock, net (in shares)										5,347
Issuance of Preferred stock, net of expenses					$ 130,138					$ 5									$ 130,133
Issuance of common stock, net (in shares)												6,287
Issuance of common stock, net	54,575											$ 6		54,569
Stock based compensation, net of withholding requirements (in shares)												166
Stock based compensation, net of withholding requirements	4,071													4,071
Common stock repurchased (in shares)												(40)
Common stock repurchased, net	(777)													(777)
Net Loss	(215,112)																			(215,112)
Other comprehensive income (loss)	(176,442)																									(176,442)
Ending balance (in shares) at Dec. 31, 2020						0		0		5,347		65,290
Ending balance at Dec. 31, 2020	$ 938,304					$ 0		$ 0		$ 5		$ 65		$ 3,033,025						$ (2,273,822)						$ 179,031

Consolidated Statement of Sto_2

Consolidated Statement of Stockholders' Equity (Parenthetical)	12 Months Ended
	Dec. 31, 2019
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201807Member
Series A Preferred Stock
Preferred stock, dividend rate	8.25%
Series B Preferred Stock
Preferred stock, dividend rate	7.875%
Series C Preferred Stock
Preferred stock, dividend rate	7.00%

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows From Operating Activities:
Net Loss	$ (215,112,000)	$ (249,905,000)	$ (105,966,000)
Adjustments to reconcile net loss to net cash and cash collateral posted to counterparties provided by (used in) operating activities:
Net amortization of premium on Agency Securities	53,322,000	53,909,000	32,989,000
Realized (gain) loss on sale of Agency Securities, available for sale	(143,877,000)	(9,611,000)	152,950,000
Credit loss expense	1,012,000	0	12,090,000
Gain on Agency Securities, trading	(19,557,000)	0	0
Loss on short sale of U.S. Treasury Securities	414,000	0	0
Stock based compensation	4,071,000	2,694,000	2,397,000
Changes in operating assets and liabilities:
Increase (decrease) in accrued interest receivable	21,828,000	(12,443,000)	(53,000)
Increase (decrease) in prepaid and other assets	7,074,000	(1,690,000)	(255,000)
Change in derivatives, at fair value	(100,692,000)	134,631,000	(58,145,000)
Increase (decrease) in accrued interest payable- repurchase agreements	(30,307,000)	21,664,000	3,816,000
Increase (decrease) in accounts payable and other accrued expenses	(1,019,000)	(821,000)	652,000
Net cash and cash collateral posted to counterparties provided by (used in) operating activities	(257,824,000)	(40,717,000)	75,223,000
Cash Flows From Investing Activities:
Purchases of Agency Securities	(5,838,937,000)	(8,937,989,000)	(4,816,961,000)
Principal repayments of Agency Securities	1,217,164,000	1,701,406,000	691,934,000
Principal repayments of Credit Risk and Non-Agency Securities	45,766,000	53,641,000	33,837,000
Proceeds from sales of Agency Securities	10,959,587,000	2,894,339,000	4,496,015,000
Disbursements on reverse repurchase agreements	(858,156,000)	0	0
Receipts from reverse repurchase agreements	858,156,000	0	0
Increase (decrease) in cash collateral posted by counterparties	29,746,000	(82,255,000)	67,620,000
Net cash and cash collateral posted to counterparties provided by (used in) investing activities	7,085,728,000	(4,389,771,000)	466,258,000
Cash Flows From Financing Activities:
Issuance of common stock, net of expenses	54,575,000	321,860,000	38,014,000
Proceeds from repurchase agreements	67,986,298,000	173,216,266,000	185,437,769,000
Principal repayments on repurchase agreements	(74,804,780,000)	(168,899,370,000)	(185,956,035,000)
Common stock dividends paid	(75,486,000)	(124,477,000)	(97,024,000)
Common stock repurchased, net	(777,000)	(16,965,000)	0
Net cash and cash collateral posted to counterparties provided by (used in) financing activities	(6,929,402,000)	4,471,455,000	(591,676,000)
Net increase (decrease) in cash and cash collateral posted to counterparties	(101,498,000)	40,967,000	(50,195,000)
Cash and cash collateral posted to counterparties - beginning of year	273,166,000	232,199,000	282,394,000
Cash and cash collateral posted to counterparties - end of year	171,668,000	273,166,000	232,199,000
Supplemental Disclosure:
Cash paid during the year for interest	183,365,000	425,746,000	252,393,000
Non-Cash Investing Activities:
Payable for unsettled purchases	0	358,712,000	166,052,000
Net unrealized gain (loss) on available for sale Agency Securities	(33,577,000)	408,954,000	(188,799,000)
Amounts receivable for issuance of preferred stock	0	5,506,000	0
Amounts payable for common stock repurchased	0	(803,000)	0
Series A Preferred Stock
Cash Flows From Financing Activities:
Redemption of Preferred stock, net of expenses	0	(54,514,000)	0
Preferred dividends paid	0	(2,249,000)	(4,498,000)
Series B Preferred Stock
Cash Flows From Financing Activities:
Redemption of Preferred stock, net of expenses	(209,583,000)	0	0
Issuance of Preferred stock, net of expenses	0	44,289,000	2,632,000
Preferred dividends paid	(1,375,000)	(13,385,000)	(12,534,000)
Series C Preferred Stock
Cash Flows From Financing Activities:
Issuance of Preferred stock, net of expenses	130,138,000	0	0
Preferred dividends paid	(8,412,000)	0	0
Credit Risk and Non-Agency Securities
Adjustments to reconcile net loss to net cash and cash collateral posted to counterparties provided by (used in) operating activities:
Amortization (accretion)	(2,849,000)	(2,956,000)	(2,946,000)
(Gain) loss on debt securities, trading	189,555,000	24,396,000	27,266,000
Cash Flows From Investing Activities:
Purchases of trading securities	(237,928,000)	(138,767,000)	0
Proceeds from sale of trading securities	889,057,000	0	97,758,000
Interest Only Securities
Adjustments to reconcile net loss to net cash and cash collateral posted to counterparties provided by (used in) operating activities:
Amortization (accretion)	0	1,924,000	4,122,000
(Gain) loss on debt securities, trading	0	(123,000)	1,007,000
Cash Flows From Investing Activities:
Proceeds from sale of trading securities	0	18,822,000	0
US Treasury Securities
Adjustments to reconcile net loss to net cash and cash collateral posted to counterparties provided by (used in) operating activities:
Amortization (accretion)	84,000	(362,000)	(1,066,000)
(Gain) loss on debt securities, trading	(21,771,000)	(2,024,000)	6,365,000
Cash Flows From Investing Activities:
Purchases of trading securities	(4,621,776,000)	(1,685,058,000)	(765,828,000)
Proceeds from sale of trading securities	$ 4,643,049,000	$ 1,786,090,000	$ 661,883,000

Organization and Nature of Busi

Organization and Nature of Business Operations	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Business Operations	Note 1 - Organization and Nature of Business Operations References to “we,” “us,” “our,” or the “Company” are to ARMOUR Residential REIT, Inc. (“ARMOUR”) and its subsidiaries. References to “ACM” are to ARMOUR Capital Management LP, a Delaware limited partnership. ARMOUR owns a 10% equity interest in BUCKLER Securities LLC ("BUCKLER"). BUCKLER is a Delaware limited liability company and a FINRA-regulated broker-dealer, controlled by ACM and certain executive officers of ARMOUR. Refer to the Glossary of Terms for definitions of capitalized terms and abbreviations used in this report. ARMOUR is an externally managed Maryland corporation incorporated in 2008. The Company is managed by ACM, an investment advisor registered with the SEC (see Note 9 - Commitments and Contingencies and Note 15 - Related Party Transactions ). We have elected to be taxed as a real estate investment trust ("REIT") under the Internal Revenue Code of 1986, as amended (the "Code"). Our qualification as a REIT depends on our ability to meet, on a continuing basis, various complex requirements under the Code relating to, among other things, the sources of our gross income, the composition and values of our assets, our distribution levels and the concentration of ownership of our capital stock. We believe that we are organized in conformity with the requirements for qualification as a REIT under the Code and our manner of operations enables us to meet the requirements for taxation as a REIT for federal income tax purposes. As a REIT, we will generally not be subject to federal income tax on the REIT taxable income that we currently distribute to our stockholders. If we fail to qualify as a REIT in any taxable year and do not qualify for certain statutory relief provisions, we will be subject to federal income tax at regular corporate rates. Even if we qualify as a REIT for U.S. federal income tax purposes, we may still be subject to some federal, state and local taxes on our income.

Basis of Presentation and Conso

Basis of Presentation and Consolidation	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Consolidation	Note 2 - Basis of Presentation and Consolidation The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the U.S. (“GAAP”). The consolidated financial statements include the accounts of ARMOUR Residential REIT, Inc. and its subsidiaries. All intercompany accounts and transactions have been eliminated. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Significant estimates affecting the accompanying consolidated financial statements include the valuation of MBS, including an assessment of the allowance for credit losses, and derivative instruments.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 3 - Summary of Significant Accounting Policies Cash Cash includes cash on deposit with financial institutions. We may maintain deposits in federally insured financial institutions in excess of federally insured limits. However, management believes we are not exposed to significant credit risk due to the financial position and creditworthiness of the depository institutions in which those deposits are held. Cash Collateral Posted To/By Counterparties Cash collateral posted to/by counterparties represents cash posted by us to counterparties or posted by counterparties to us as collateral. Cash collateral posted to/by counterparties may include collateral for interest rate swap contracts (including swaptions and basis swap contracts), and repurchase agreements on our MBS and our Agency Securities purchased or sold on a to-be-announced basis ("TBA Agency Securities"). Investments in Securities, at Fair Value Our investments in securities are generally classified as either available for sale or trading securities. Management determines the appropriate classifications of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. Available for Sale Securities represent investments that we intend to hold for extended periods of time and are reported at their estimated fair values with unrealized gains and losses excluded from earnings and reported as part of the consolidated statements of comprehensive income (loss). Trading Securities are reported at their estimated fair values with gains and losses included in Other Income (Loss) as a component of the consolidated statements of operations. Receivables and Payables for Unsettled Sales and Purchases We account for purchases and sales of securities on the trade date, including purchases and sales for forward settlement. Receivables and payables for unsettled trades represent the agreed trade price multiplied by the outstanding balance of the securities at the balance sheet date. Accrued Interest Receivable and Payable Accrued interest receivable includes interest accrued between payment dates on securities and interest on unsettled sales of securities. Accrued interest payable includes interest on unsettled purchases of securities and interest on repurchase agreements. At certain times, we may have interest payable on U.S. Treasury Securities sold short. Repurchase Agreements We finance the acquisition of the majority of our MBS through the use of repurchase agreements. Our repurchase agreements are secured by our MBS and bear interest rates that have historically moved in close relationship to the Federal Funds Rate and short-term London Interbank Offered Rate ("LIBOR"). Under these repurchase agreements, we sell MBS to a lender and agree to repurchase the same MBS in the future for a price that is higher than the original sales price. The difference between the sales price that we receive and the repurchase price that we pay represents interest paid to the lender, which accrues over the life of the repurchase agreement. A repurchase agreement operates as a financing arrangement under which we pledge our MBS as collateral to secure a loan which is equal in value to a specified percentage of the estimated fair value of the pledged collateral. We retain beneficial ownership of the pledged collateral. At the maturity of a repurchase agreement, we are required to repay the loan and concurrently receive back our pledged collateral from the lender or, with the consent of the lender, we may renew such agreement at the then prevailing interest rate. The repurchase agreements may require us to pledge additional assets to the lender in the event the estimated fair value of the existing pledged collateral declines. In addition to the repurchase agreement financing discussed above, at certain times we have entered into reverse repurchase agreements with certain of our repurchase agreement counterparties. Under a typical reverse repurchase agreement, we purchase U.S. Treasury Securities from a borrower in exchange for cash and agree to sell the same securities in the future in exchange for a price that is higher than the original purchase price. The difference between the purchase price originally paid and the sale price represents interest received from the borrower. Reverse repurchase agreement receivables and repurchase agreement liabilities are presented net when they meet certain criteria, including being with the same counterparty, being governed by the same master repurchase agreement ("MRA"), settlement through the same brokerage or clearing account and maturing on the same day. We did not have any reverse repurchase agreements outstanding at December 31, 2020 and December 31, 2019. Derivatives, at Fair Value We recognize all derivatives individually as either assets or liabilities at fair value on our consolidated balance sheets. All changes in the fair values of our derivatives are reflected in our consolidated statements of operations. We designate derivatives as hedges for tax purposes and any unrealized derivative gains or losses would not affect our distributable net taxable income. These transactions may include interest rate swap contracts, interest rate swaptions and basis swap contracts. We also may utilize forward contracts for the purchase or sale of TBA Agency Securities. We account for TBA Agency Securities as derivative instruments if it is reasonably possible that we will not take or make physical delivery of the Agency Security upon settlement of the contract. We account for TBA dollar roll transactions as a series of derivative transactions. We may also purchase and sell TBA Agency Securities as a means of investing in and financing Agency Securities (thereby increasing our “at risk” leverage) or as a means of disposing of or reducing our exposure to Agency Securities (thereby reducing our “at risk” leverage). We agree to purchase or sell, for future delivery, Agency Securities with certain principal and interest terms and certain types of collateral, but the particular Agency Securities to be delivered are not identified until shortly before the TBA settlement date. We may also choose, prior to settlement, to move the settlement of these securities out to a later date by entering into an offsetting short or long position (referred to as a “pair off”), net settling the paired off positions for cash, and simultaneously purchasing or selling a similar TBA Agency Security for a later settlement date. This transaction is commonly referred to as a “dollar roll.” When it is reasonably possible that we will pair off a TBA Agency Security, we account for that contract as a derivative. Impairment of Assets We assess impairment of available for sale securities at least on a quarterly basis and more frequently when economic or market concerns warrant such evaluation. We consider an impairment if we (1) intend to sell the available for sale securities, or (2) believe it is more likely than not that we will be required to sell the securities before recovery (for example, because of liquidity requirements or contractual obligations) and a credit impairment exists where fair value is less than amortized cost. Impairment losses recognized establish a new cost basis for the related available for sale securities. Revenue Recognition Interest income is earned and recognized on Agency Securities based on their unpaid principal amounts and their contractual terms. Recognition of interest income commences on the settlement date of the purchase transaction and continues through the settlement date of the sale transaction. Premiums and discounts associated with the purchase of Multi-Family MBS, which are generally not subject to prepayment, are amortized or accreted into interest income over the contractual lives of the securities using a level yield method. Premiums and discounts associated with the purchase of other Agency Securities are amortized or accreted into interest income over the actual lives of the securities, reflecting actual prepayments as they occur. Purchase and sale transactions (including TBA Agency Securities) are recorded on the trade date to the extent it is probable that we will take or make timely physical delivery of the related securities. Gains or losses realized from sales of available for sale securities are reclassified into income from other comprehensive income and are determined using the specific identification method. Interest income on Credit Risk and Non-Agency Securities and Interest-Only Securities is recognized using the effective yield method over the life of the securities based on the future cash flows expected to be received. Future cash flow projections and related effective yields are determined for each security and updated quarterly. Impairment losses establish a new cost basis in the security for purposes of calculating effective yields, recognized when the fair value of a security is less than its cost basis and there has been an adverse change in the future cash flows expected to be received. Other changes in future cash flows expected to be received are recognized prospectively over the remaining life of the security. Interest income on U.S. Treasury Securities is recognized based on their unpaid principal amounts and their contractual terms. Recognition of interest income commences on the settlement date of the purchase transaction and continues through the settlement date of the sale transaction. Comprehensive Income (Loss) Comprehensive income (loss) refers to changes in equity during a period from transactions and other events and circumstances from non-owner sources. It includes all changes in equity during a period, except those resulting from investments by owners and distributions to owners.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2020
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	Note 4 - Recent Accounting Pronouncements We consider the applicability and impact of all Accounting Standards Updates ("ASU") issued by the Financial Accounting Standards Board. Those not listed below were deemed to be either not applicable, are not expected to have a significant impact on our consolidated financial statements when adopted, or did not have a significant impact on our consolidated financial statements upon adoption. Accounting Standard Description ASU 2016-13, Financial Instruments–Credit Losses (Topic 326) The standard introduces a new model for recognizing credit losses on financial instruments based on an estimate of current expected credit losses. The standard applies to (1) loans, accounts receivable, trade receivables, and other financial assets measured at amortized cost, (2) loan commitments and certain other off–balance sheet credit exposures, (3) debt securities and other financial assets measured at fair value through other comprehensive income, and (4) beneficial interests in securitized financial assets. The standard was effective for fiscal years beginning after December 15, 2019. The adoption of the standard on January 1, 2020 did not have a significant impact on the Company, since at that time we did not intend to sell our investments in available for sale Agency Securities. The Company determined that it was not more likely than not that we would be required to sell the investments before recovery of their amortized cost bases as the contractual cash flows of these federal agency mortgage backed securities are guaranteed by an agency of the U.S. government and we expected that all securities would not be settled at a price less than their amortized cost.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Note 5 - Fair Value of Financial Instruments Our valuation techniques for financial instruments use observable and unobservable inputs. Observable inputs reflect readily obtainable data from third party sources, while unobservable inputs reflect management’s market assumptions. The Accounting Standards Codification Topic No. 820, "Fair Value Measurement," classifies these inputs into the following hierarchy: Level 1 Input s - Quoted prices for identical instruments in active markets. Level 2 Inputs - Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable. Level 3 Inputs - Prices determined using significant unobservable inputs. Unobservable inputs may be used in situations where quoted prices or observable inputs are unavailable (for example, when there is little or no market activity for an investment at the end of the period). Unobservable inputs reflect management’s assumptions about the factors that market participants would use in pricing an asset or liability, and would be based on the best information available. At the beginning of each quarter, we assess the assets and liabilities that are measured at fair value on a recurring basis to determine if any transfers between levels in the fair value hierarchy are needed. The following describes the valuation methodologies used for our assets and liabilities measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy. Any transfers between levels are assumed to occur at the beginning of the reporting period. Investment in Securities: Fair value for our investments in securities are based on obtaining a valuation for each security from third party pricing services and/or dealer quotes. The third party pricing services use common market pricing methods that may include pricing models that may incorporate such factors as coupons, prepayment speeds, spread to the Treasury curves and interest rate swap curves, duration, periodic and life caps and credit enhancement. If the fair value of a security is not available from the third party pricing services or such data appears unreliable, we obtain pricing indications from up to three dealers who make markets in similar securities. Management reviews pricing used to ensure that current market conditions are properly reflected. This review includes, but is not limited to, comparisons of similar market transactions or alternative third party pricing services, dealer pricing indications and comparisons to a third party pricing model. Fair values obtained from the third party pricing services for similar instruments are classified as Level 2 securities if the inputs to the pricing models used are consistent with the Level 2 definition. If quoted prices for a security are not reasonably available from the third party pricing service, but dealer pricing indications are, the security will be classified as a Level 2 security. If neither is available, management will determine the fair value based on characteristics of the security that we receive from the issuer and based on available market information and classify it as a Level 3 security. U.S. Treasury Securities are classified as Level 1, as quoted unadjusted prices are available in active markets for identical assets. Derivatives: The fair values of our interest rate swap contracts, interest rate swaptions and basis swaps are valued using information provided by third party pricing services that incorporate common market pricing methods that may include current interest rate curves, forward interest rate curves and market spreads to interest rate curves. We estimate the fair value of TBA Agency Securities based on similar methods used to value our Agency Securities. Management compares the pricing information received to dealer quotes to ensure that the current market conditions are properly reflected. The fair values of our derivatives are classified as Level 2. The following table provides a summary of our assets and liabilities that are measured at fair value on a recurring basis at December 31, 2020 and December 31, 2019. December 31, 2020 (Level 1) (Level 2) (Level 3) Balance Assets at Fair Value: Agency Securities $ — $ 5,178,322 $ — $ 5,178,322 Derivatives $ — $ 54,686 $ — $ 54,686 Liabilities at Fair Value: Derivatives $ — $ 1,217 $ — $ 1,217 December 31, 2019 (Level 1) (Level 2) (Level 3) Balance Assets at Fair Value: Agency Securities $ — $ 11,941,766 $ — $ 11,941,766 Credit Risk and Non-Agency Securities $ — $ 883,601 $ — $ 883,601 Derivatives $ — $ 24,751 $ — $ 24,751 Liabilities at Fair Value: $ — Derivatives $ — $ 71,974 $ — $ 71,974 There were no transfers of assets or liabilities between the levels of the fair value hierarchy during the year ended December 31, 2020 or for the year ended December 31, 2019. Excluded from the tables above are financial instruments, including cash, cash collateral posted to/by counterparties, receivables, the Subordinated loan to BUCKLER, payables and borrowings under repurchase agreements, which are presented in our consolidated financial statements at cost which approximates fair value. The estimated fair value of these instruments is measured using "Level 1" or "Level 2" inputs at December 31, 2020 and December 31, 2019.

Investment In Securities

Investment In Securities	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Investments In Securities	Note 6 - Investments in Securities As of December 31, 2020 and December 31, 2019, our securities portfolio consisted of $5,178,322 and $12,825,367 of investment securities, at fair value, respectively, and $2,711,977 and $1,006,280 of TBA Agency Securities, at fair value, respectively. Our TBA Agency Securities are reported at net carrying value of $19,747 and $(592), at December 31, 2020 and December 31, 2019, respectively, and are reported in Derivatives, at fair value on our consolidated balance sheets (see Note 8 - Derivatives) . The net carrying value of our TBA Agency Securities represents the difference between the fair value of the underlying Agency Security in the TBA contract and the cost basis or the forward price to be paid or received for the underlying Agency Security. The following tables summarize our investment in securities as of December 31, 2020 and December 31, 2019, excluding TBA Agency Securities (see Note 8 - Derivatives) . Beginning in the second quarter of 2020, we designated Agency MBS purchased as “trading securities” for financial reporting purposes, and consequently, fair value changes for these investments will be reported in net income. We anticipate continuing this designation for newly acquired Agency MBS positions because it is more representative of our results of operations insofar as the fair value changes for these securities are presented in a manner consistent with the presentation and timing of the fair value changes of our hedging instruments. Fair value changes for the legacy Agency Securities designated as available for sale will continue to be reported in other comprehensive income as required by GAAP. Available for Sale Trading Securities Agency Agency Credit Risk and Non-Agency Interest-Only U.S. Treasuries Totals December 31, 2020 Balance, December 31, 2019 $ 11,941,766 $ — $ 883,601 $ — $ — $ 12,825,367 Purchases (1) 1,768,688 3,711,961 237,928 — 4,621,776 10,340,353 Proceeds from sales (10,800,879) (158,708) (889,057) — (4,643,049) (16,491,693) Principal repayments (873,650) (343,514) (45,766) — — (1,262,930) Gains (losses) (32,565) 19,557 (189,555) — 21,357 (181,206) Credit loss expense (1,012) — — — — (1,012) Amortization/accretion (31,446) (21,876) 2,849 — (84) (50,557) Balance, December 31, 2020 $ 1,970,902 $ 3,207,420 $ — $ — $ — $ 5,178,322 Percentage of Portfolio 38.06 % 61.94 % — % — % — % 100.00 % December 31, 2019 Balance, December 31, 2018 $ 7,051,954 — $ 819,915 $ 20,623 $ 98,646 $ 7,991,138 Purchases (1) 9,130,512 — 138,767 — 1,685,058 $ 10,954,337 Sales (2,894,339) — — (18,822) (1,786,090) $ (4,699,251) Principal Repayments (1,701,406) — (53,641) — — $ (1,755,047) Losses 408,954 — (24,396) 123 2,024 $ 386,705 Amortization/accretion (53,909) — 2,956 (1,924) 362 $ (52,515) Balance, December 31, 2019 $ 11,941,766 $ — $ 883,601 $ — $ — $ 12,825,367 Percentage of Portfolio 93.11 % — % 6.89 % — % — % 100.00 % (1) Purchases include cash paid during the period, plus payable for investment securities purchased during the period as of period end. Available for Sale Securities: During year ended December 31, 2020, we evaluated our available for sale securities to determine if the available sale securities in an unrealized loss position were impaired. In the first quarter of 2020, we recognized an impairment of $1,012 in our consolidated statements of operations as we had determined that we may have been required to sell certain securities in the near future. No credit loss expense was required for the remainder of 2020. We do not have an allowance for credit losses as all of our available for sale securities consist of Agency MBS. At December 31, 2019 and December 31, 2018, we evaluated our available for sale securities with unrealized losses to determine whether there was an other than temporary impairment ("OTTI"). At those dates, we also considered whether we intended to sell available for sale securities and whether it was more likely than not that we could meet our liquidity requirements and contractual obligations without selling available for sale securities. No OTTI was recognized for the year ended December 31, 2019. During the first quarter of 2018, we recognized additional losses on available for sale securities, previously identified during 2017, totaling $12,090 in our consolidated financial statements of operations. We determined that there was no OTTI of our remaining available for sale securities for the year ended December 31, 2018. The table below presents the components of the carrying value and the unrealized gain or loss position of our available for sale securities at December 31, 2020 and December 31, 2019. Our available for sale securities had a weighted average coupon of 3.25% and 3.76% at December 31, 2020 and December 31, 2019. Agency Securities Principal Amount Amortized Cost Gross Unrealized Loss Gross Unrealized Gain Fair Value December 31, 2020 Total Fannie Mae $ 1,359,136 $ 1,397,206 $ (1) $ 159,603 $ 1,556,808 Total Freddie Mac 354,382 368,686 — 19,246 387,932 Total Ginnie Mae 25,388 25,979 (43) 226 26,162 Total $ 1,738,906 $ 1,791,871 $ (44) $ 179,075 $ 1,970,902 December 31, 2019 Total Fannie Mae $ 8,779,331 $ 8,975,140 $ (291) $ 294,937 $ 9,269,786 Total Freddie Mac 2,522,870 2,587,512 (40) 61,323 2,648,795 Total Ginnie Mae 22,504 23,641 (461) 5 23,185 Total $ 11,324,705 $ 11,586,293 $ (792) $ 356,265 $ 11,941,766 The following table presents the unrealized losses and estimated fair value of our available for sale securities by length of time that such securities have been in a continuous unrealized loss position at December 31, 2020 and December 31, 2019. All of our available for sale securities are issued and guaranteed by GSEs or Ginnie Mae. The GSEs have a long term credit rating of AA+. Unrealized Loss Position For: < 12 Months ≥ 12 Months Total Agency Securities Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses December 31, 2020 $ 8,811 $ (44) $ — $ — $ 8,811 $ (44) December 31, 2019 $ 2,136 $ (10) $ 43,939 $ (782) $ 46,075 $ (792) Actual maturities of available for sale securities are generally shorter than stated contractual maturities because actual maturities of available for sale securities are affected by the contractual lives of the underlying mortgages, periodic payments of principal and prepayments of principal. The following table summarizes the weighted average lives of our available for sale securities at December 31, 2020 and December 31, 2019. December 31, 2020 December 31, 2019 Weighted Average Life of Fair Value Amortized Fair Value Amortized < 1 year $ 71 $ 72 $ — $ — ≥ 1 year and < 3 years 548,352 520,657 22,237 22,254 ≥ 3 years and < 5 years 282,739 269,716 6,542,389 6,365,623 ≥ 5 years 1,139,740 1,001,426 5,377,140 5,198,416 Total Available for Sale Securities $ 1,970,902 $ 1,791,871 $ 11,941,766 $ 11,586,293 We use a third party model to calculate the weighted average lives of our available for sale securities. Weighted average life is calculated based on expectations for estimated prepayments for the underlying mortgage loans of our available for sale securities. These estimated prepayments are based on assumptions such as interest rates, current and future home prices, housing policy and borrower incentives. The weighted average lives of our available for sale securities at December 31, 2020 and December 31, 2019 in the table above are based upon market factors, assumptions, models and estimates from the third party model and also incorporate management’s judgment and experience. The actual weighted average lives of our available for sale securities could be longer or shorter than estimated. Trading Securities: The components of the carrying value of our trading securities at December 31, 2020 and December 31, 2019 are presented in the table below. We did not have any Credit Risk and Non-Agency Securities, U.S. Treasury Securities or Interest-Only Securities at December 31, 2020. We did not have any U.S. Treasury Securities or Interest-Only Securities at December 31, 2019. Principal Amount Amortized Cost Gross Unrealized Loss Gross Unrealized Gain Fair Value December 31, 2020 Agency Securities: Total Fannie Mae $ 2,420,828 $ 2,585,409 $ (1,441) $ 18,211 $ 2,602,179 Total Freddie Mac 570,654 601,320 (430) 4,351 605,241 Total Trading Securities $ 2,991,482 $ 3,186,729 $ (1,871) $ 22,562 $ 3,207,420 December 31, 2019 Credit Risk Transfer $ 754,729 $ 751,940 $ — $ 52,024 $ 803,964 Non-Agency Securities 93,723 72,904 (3) 6,736 79,637 Total Trading Securities $ 848,452 $ 824,844 $ (3) $ 58,760 $ 883,601 Our Credit Risk Transfer securities were collateralized by residential mortgage loans meeting agency criteria. However, our securities' principal and interest are not guaranteed by the agencies. Credit Risk Transfer securities include tranches issued since 2014. Our Non-Agency Securities are collateralized by residential mortgage loans not guaranteed by any agency and include legacy securities issued between 2005 and 2007. The following table summarizes the weighted average lives of our trading securities at December 31, 2020 and December 31, 2019. December 31, 2020 December 31, 2019 Estimated Weighted Average Life of Trading Securities Fair Value Amortized Cost Fair Value Amortized Cost < 1 year $ — $ — $ — $ — ≥ 1 year and < 3 years 649,425 650,328 389,883 369,600 ≥ 3 years and < 5 years 1,522,509 1,506,035 407,656 375,030 ≥ 5 years 1,035,486 1,030,366 86,062 80,214 Total $ 3,207,420 $ 3,186,729 $ 883,601 $ 824,844 We use a third party model to calculate the weighted average lives of our trading securities. Weighted average life is calculated based on expectations for estimated prepayments for the underlying mortgage loans of our trading securities. These estimated prepayments are based on assumptions such as interest rates, current and future home prices, housing policy and borrower incentives. The weighted average lives of our trading securities at December 31, 2020 and December 31, 2019 in the tables above are based upon market factors, assumptions, models and estimates from the third party model and also incorporate management’s judgment and experience. The actual weighted average lives of our trading securities could be longer or shorter than estimated.

Repurchase Agreements

Repurchase Agreements	12 Months Ended
	Dec. 31, 2020
Disclosure of Repurchase Agreements [Abstract]
Repurchase Agreements	Note 7 - Repurchase Agreements At December 31, 2020, we had MRAs with 33 counterparties and had $4,536,065 in outstanding borrowings with 18 of those counterparties. At December 31, 2019, we had MRAs with 49 counterparties and had $11,354,547 in outstanding borrowings with 25 of those counterparties. The following table represents the contractual repricing regarding our repurchase agreements to finance MBS purchases at December 31, 2020 and December 31, 2019. No amounts below are subject to offsetting. Balance Weighted Average Contractual Rate Weighted Average Maturity in days Haircut (1) December 31, 2020 Agency Securities ≤ 30 days $ 3,618,255 0.23 % 15 3.12 % > 30 days to ≤ 60 days 917,810 0.23 % 45 3.20 % Total or Weighted Average $ 4,536,065 0.23 % 21 3.13 % December 31, 2019 Agency Securities ≤ 30 days $ 10,241,137 2.56 % 8 4.35 % > 30 days to ≤ 60 days 426,147 1.99 % 34 4.61 % Total or Weighted Average 10,667,284 2.54 % 9 4.36 % Credit Risk and Non-Agency Securities ≤ 30 days 687,263 2.45 % 15 16.25 % Total or Weighted Average $ 11,354,547 2.54 % 9 5.16 % (1) The Haircut represents the weighted average margin requirement, or the percentage amount by which the collateral value must exceed the loan amount. Our repurchase agreements require that we maintain adequate pledged collateral. A decline in the value of the MBS pledged as collateral for borrowings under repurchase agreements could result in the counterparties demanding additional collateral pledges or liquidation of some of the existing collateral to reduce borrowing levels. We manage this risk by maintaining an adequate balance of available cash and unpledged securities. An event of default or termination event under the standard MRA would give our counterparty the option to terminate all repurchase transactions existing with us and require any amount due to be payable immediately. In addition, certain of our MRAs contain a restriction that prohibits our leverage from exceeding twelve times our stockholders’ equity as well as termination events in the case of significant reductions in equity capital. We also may receive cash or securities as collateral from our derivative counterparties which we may use as additional collateral for repurchase agreements. Certain interest rate swap contracts provide for cross collateralization and cross default with repurchase agreements and other contracts with the same counterparty. At December 31, 2020 and December 31, 2019, BUCKLER accounted for 66.1% and 45.0%, respectively, of our aggregate borrowings and had an amount at risk of 8.3% and 14.8%, respectively, of our total stockholders' equity with a weighted average maturity of 21 days and 7 days, respectively, on repurchase agreements (See Note 15 - Related Party Transactions ). In addition, at December 31, 2020, we had 1 repurchase agreement counterparty that individually accounted for between 5% and 10% of our aggregate borrowings. In total, this counterparty accounted for approximately 9.0% of our repurchase agreement borrowings outstanding at December 31, 2020. At December 31, 2019, we had 2 repurchase agreement counterparties that individually accounted for between 5% and 10% of our aggregate borrowings. In total, these counterparties accounted for 12.7% of our repurchase agreement borrowings at December 31, 2019.

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Note 8 - Derivatives We enter into derivative transactions to manage our interest rate risk and agency mortgage rate exposures. We have agreements with our derivative counterparties that provide for the posting of collateral based on the fair values of our derivatives. Through this margin process, either we or our counterparties may be required to pledge cash or securities as collateral. Collateral requirements vary by counterparty and change over time based on the fair value, notional amount and remaining term of the contracts. Certain contracts provide for cross collateralization and cross default with repurchase agreements and other contracts with the same counterparty. Interest rate swap contracts are designed to lock in funding costs for repurchase agreements associated with our assets in such a way to help assure the realization of net interest margins. Such transactions are based on assumptions about prepayments which, if not realized, will cause transaction results to differ from expectations. Interest rate swaptions generally provide us the option to enter into an interest rate swap agreement at a certain point of time in the future with a predetermined notional amount, stated term and stated rate of interest in the fixed leg and interest rate index on the floating leg. Basis swap contracts allow us to exchange one floating interest rate basis for another, thereby allowing us to diversify our floating rate basis exposures. TBA Agency Securities are forward contracts for the purchase (“long position”) or sale (“short position”) of Agency Securities at a predetermined price, face amount, issuer, coupon and stated maturity on an agreed-upon future date. The specific Agency Securities delivered into the contract upon the settlement date, published each month by the Securities Industry and Financial Markets Association, are not known at the time of the transaction. We may enter into TBA Agency Securities as a means of hedging against short-term changes in interest rates. We may also enter into TBA Agency Securities as a means of acquiring or disposing of Agency Securities and we may from time to time utilize TBA dollar roll transactions to finance Agency Security purchases. We estimate the fair value of TBA Agency Securities based on similar methods used to value our Agency Securities. We have netting arrangements in place with all derivative counterparties pursuant to standard documentation developed by ISDA. We are also required to post or hold cash collateral based upon the net underlying market value of our open positions with the counterparty. A decline in the value of the open positions with the counterparty could result in the counterparties demanding additional collateral pledges or liquidation of some of the existing collateral to reduce borrowing levels. We manage this risk by maintaining an adequate balance of available cash and unpledged securities. An event of default or termination event under the standard ISDA would give our counterparty the option to terminate all repurchase transactions existing with us and require any amount due to be payable immediately. In addition, certain of our ISDAs contain a restriction that prohibits our leverage from exceeding twelve times our stockholders’ equity as well as termination events in the case of significant reductions in equity capital. During the year ended December 31, 2020, we received waivers from certain ISDA counterparties related to significant reductions in equity capital that would have otherwise caused a default or termination event. The following tables present information about the potential effects of netting our derivatives if we were to offset the assets and liabilities on the accompanying consolidated balance sheets. We currently present these financial instruments at their gross amounts and they are included in derivatives, at fair value on the accompanying consolidated balance sheets at December 31, 2020 and December 31, 2019. Gross Amounts Not Offset Assets Gross Amounts (1) Financial Cash Collateral Total Net December 31, 2020 Interest rate swap contracts $ 34,588 $ (866) $ (27,773) $ 5,949 TBA Agency Securities 20,098 (351) (13,942) 5,805 Totals $ 54,686 $ (1,217) $ (41,715) $ 11,754 December 31, 2019 Interest rate swap contracts $ 23,659 $ (70,290) $ 83,066 $ 36,435 TBA Agency Securities 1,092 (1,092) — — Totals $ 24,751 $ (71,382) $ 83,066 $ 36,435 (1) See Note 5, “Fair Value of Financial Instruments” for additional discussion. Gross Amounts Not Offset Liabilities Gross Amounts (1) Financial Cash Collateral Total Net December 31, 2020 Interest rate swap contracts $ (866) $ 866 $ — $ — TBA Agency Securities (351) 351 — — Totals $ (1,217) $ 1,217 $ — $ — December 31, 2019 Interest rate swap contracts $ (70,290) $ 70,290 $ — $ — TBA Agency Securities (1,684) 1,092 377 (215) Totals $ (71,974) $ 71,382 $ 377 $ (215) (1) See Note 5, “Fair Value of Financial Instruments” for additional discussion. The following table represents the location and information regarding our derivatives which are included in Other Income (Loss) in the accompanying consolidated statements of operations for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. Income (Loss) Recognized For the Years Ended Derivatives Location on consolidated statements of operations December 31, 2020 December 31, 2019 December 31, 2018 Interest rate swap contracts: Realized gain (loss) Realized loss on derivatives $ (461,374) $ (237,725) $ 2,655 Interest income Realized loss on derivatives 30,076 187,899 124,714 Interest expense Realized loss on derivatives (46,069) (162,529) (124,241) Changes in fair value Unrealized gain (loss) on derivatives 81,287 (132,303) 43,755 $ (396,080) $ (344,658) $ 46,883 TBA Agency Securities: Realized gain (loss) Realized loss on derivatives 99,159 (1,641) (50,625) Changes in fair value Unrealized gain (loss) on derivatives 12,768 (3,824) 5,561 $ 111,927 $ (5,465) $ (45,064) Totals $ (284,153) $ (350,123) $ 1,819 The following tables present information about our derivatives at December 31, 2020 and December 31, 2019. Interest Rate Swaps (1) Notional Amount Weighted Average Remaining Term (Months) Weighted Average Rate December 31, 2020 < 3 years $ 2,230,000 12 0.06 % ≥ 3 years and < 5 years 463,000 45 0.14 % ≥ 5 years and < 7 years 942,000 72 0.28 % ≥ 7 years 1,702,000 113 0.50 % Total or Weighted Average (2) $ 5,337,000 58 0.24 % December 31, 2019 < 3 years $ 2,750,000 19 1.66 % ≥ 3 years and < 5 years 2,850,000 47 1.84 % ≥ 5 years and < 7 years 1,200,000 83 1.86 % ≥ 7 years 1,175,000 118 1.54 % Total or Weighted Average (3) $ 7,975,000 53 1.74 % (1) Pay Fixed/Receive Variable (2) Of this amount, $2,230,000 notional are SOFR based swaps, the last of which matures in 2023; and $3,107,000 notional are Fed Funds based swaps, the last of which matures in 2030. (3) Of this amount, $1,025,000 notional are LIBOR based swaps, the last of which matures in 2023; $375,000 notional are SOFR based swaps, the last of which matures in 2024; and $6,575,000 notional are Fed Funds based swaps, the last of which matures in 2029. TBA Agency Securities Notional Amount Cost Basis Fair Value December 31, 2020 15 Year Long 1.5% $ 200,000 $ 204,758 $ 205,781 2.0% 1,200,000 1,248,015 1,253,354 30 Year Long 2.0% 600,000 619,031 622,934 2.5% 800,000 838,047 841,314 3.5% (200,000) (211,055) (211,406) Total (1) $ 2,600,000 $ 2,698,796 $ 2,711,977 December 31, 2019 15 Year Long 3.0% $ 500,000 $ 511,055 $ 511,885 30 Year Long 2.5% 500,000 494,813 494,395 Total (2) $ 1,000,000 $ 1,005,868 $ 1,006,280 (1) $1,250,000 notional are forward settling. (2) $1,000,000 notional are forward settling.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 9 - Commitments and Contingencies Management The Company is managed by ACM, pursuant to management agreements with ARMOUR and JAVELIN (see also Note 15, “ Related Party Transactions” ) . The management agreements entitle ACM to receive a management fee payable monthly in arrears. Currently, the monthly ARMOUR management fee is 1/12th of the sum of (a) 1.5% of gross equity raised up to $1.0 billion plus (b) 0.75% of gross equity raised in excess of $1.0 billion. The cost of repurchased stock and any dividend representing a return of capital for tax purposes will reduce the amount of gross equity raised used to calculate the monthly management fee. At December 31, 2020, December 31, 2019 and December 31, 2018, the effective ARMOUR management fee, prior to management fees waived was 1.00%, 1.00% and 1.03% based on gross equity raised of $2,944,169, $2,965,163 and $2,658,969, respectively. ACM began waiving 40% of its management fee during the second quarter of 2020. As of December 31, 2020, ACM has waived management fees of $8,855. On January 13, 2021, ACM notified ARMOUR that it intended to adjust the fee waiver to the rate of $2,400 for the first quarter of 2021 and $800 per month thereafter until further notice (see Note 16 - Subsequent Events ). The ACM monthly management fees are not calculated based on the performance of our assets. Accordingly, the payment of our monthly management fees may not decline in the event of a decline in our earnings and may cause us to incur losses. We are also responsible for any costs and expenses that ACM incurred solely on behalf of ARMOUR or JAVELIN other than the various overhead expenses specified in the terms of the management agreements. ACM is further entitled to receive termination fees from ARMOUR and JAVELIN under certain circumstances. Indemnifications and Litigation We enter into certain contracts that contain a variety of indemnifications, principally with ACM and underwriters, against third party claims for errors and omissions in connection with their services to us. We have not incurred any costs to defend lawsuits or settle claims related to these indemnification agreements. As a result, the estimated fair value of these agreements, as well as the maximum amount attributable to past events, is not material. Accordingly, we have no liabilities recorded for these agreements at December 31, 2020 and December 31, 2019. Nine putative class action lawsuits have been filed in connection with the tender offer (the “Tender Offer”) and merger (the “Merger”) for JAVELIN. The Tender Offer and Merger are collectively defined herein as the “Transactions.” All nine suits name ARMOUR, the previous members of JAVELIN’s board of directors prior to the Merger (of which eight are current members of ARMOUR’s board of directors) (the “Individual Defendants”) and JMI Acquisition Corporation (“Acquisition” ) as defendants. Certain cases also name ACM and JAVELIN as additional defendants. The lawsuits were brought by purported holders of JAVELIN’s common stock, both individually and on behalf of a putative class of JAVELIN’s stockholders, alleging that the Individual Defendants breached their fiduciary duties owed to the plaintiffs and the putative class of JAVELIN stockholders, including claims that the Individual Defendants failed to properly value JAVELIN; failed to take steps to maximize the value of JAVELIN to its stockholders; ignored or failed to protect against conflicts of interest; failed to disclose material information about the Transactions; took steps to avoid competitive bidding and to give ARMOUR an unfair advantage by failing to adequately solicit other potential acquirors or alternative transactions; and erected unreasonable barriers to other third-party bidders. The suits also allege that ARMOUR, JAVELIN, ACM and Acquisition aided and abetted the alleged breaches of fiduciary duties by the Individual Defendants. The lawsuits seek equitable relief, including, among other relief, to enjoin consummation of the Transactions, or rescind or unwind the Transactions if already consummated, and award costs and disbursements, including reasonable attorneys’ fees and expenses. The sole Florida lawsuit was never served on the defendants, and that case was voluntarily dismissed and closed on January 20, 2017 . On April 25, 2016, the Maryland court issued an order consolidating the eight Maryland cases into one action, captioned In re JAVELIN Mortgage Investment Corp. Shareholder Litigation (Case No. 24-C-16-001542), and designated counsel for one of the Maryland cases as interim lead co-counsel. On May 26, 2016, interim lead counsel filed the Consolidated Amended Class Action Complaint for Breach of Fiduciary Duty asserting consolidated claims of breach of fiduciary duty, aiding and abetting the breaches of fiduciary duty, and waste. On June 27, 2016, defendants filed a Motion to Dismiss the Consolidated Amended Class Action Complaint for failing to state a claim upon which relief can be granted. A hearing was held on the Motion to Dismiss on March 3, 2017, and the Court reserved ruling. On September 27, 2019, the court further deferred the matter for six months. On June 15, 2020, co-counsel for the plaintiff filed a notice of supplemental authority requesting to move the matter forward. On August 19, 2020, a Notification To Parties of Contemplated Dismissal was sent out by the Clerk of the Circuit Court to all parties. Counsel for the plaintiff responded on August 24, 2020, with a Motion to Defer Dismissal. No further action has been taken by the court. Each of ARMOUR, JAVELIN, ACM and the Individual Defendants intends to defend the claims made in these lawsuits vigorously; however, there can be no assurance that any of ARMOUR, JAVELIN, ACM or the Individual Defendants will prevail in its defense of any of these lawsuits to which it is a party. An unfavorable resolution of any such litigation surrounding the Transactions may result in monetary damages being awarded to the plaintiffs and the putative class of former stockholders of JAVELIN and the cost of defending the litigation, even if resolved favorably, could be substantial. Due to the preliminary nature all of these suits, ARMOUR is not able at this time to estimate their outcome.

Stock Based Compensation

Stock Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Stock Based Compensation	Note 10 - Stock Based Compensation We adopted the 2009 Stock Incentive Plan as amended (the “Plan”) to attract, retain and reward directors and other persons who provide services to us in the course of operations. The Plan authorizes the Board to grant awards including common stock, restricted shares of common stock (“RSUs”), stock options, performance shares, performance units, stock appreciation rights and other equity and cash-based awards (collectively, “Awards”), subject to terms as provided in the Plan. At December 31, 2020, there were 677 shares available for future issuance under the Plan. In January 2021, we granted 535 RSUs to ACM and 100 RSUs to the Board, leaving 42 shares available for issuance. Transactions related to awards for the years ended December 31, 2020, December 31, 2019 and December 31, 2018 are summarized below: December 31, 2020 December 31, 2019 December 31, 2018 Number of Awards Weighted Number of Awards Weighted Number of Awards Weighted Unvested RSU Awards Outstanding beginning of period 247 $ 24.82 360 $ 24.82 472 $ 24.82 Granted (1) 502 $ 17.85 6 $ 18.71 — $ — Vested (205) $ 20.41 (119) $ 18.05 (112) $ 22.70 Forfeited (48) $ 23.14 — $ — — $ — Unvested RSU Awards Outstanding end of period 496 $ 19.77 247 $ 24.82 360 $ 24.82 (1) During the year ended December 31, 2020, we granted 358 RSUs to ACM and 144 RSUs to the Board.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Stockholders' Equity	Note 11 - Stockholders' Equity Preferred Stock At December 31, 2020 and December 31, 2019, we were authorized to issue up to 50,000 shares of preferred stock, par value $0.001 per share, with such designations, voting and other rights and preferences as may be determined from time to time by our Board of Directors (“Board”) or a committee thereof. On June 24, 2019, we filed Articles Supplementary with the State Department of Assessments and Taxation of the State of Maryland (the “Department”) to designate 10,320 shares of the Company’s authorized preferred stock, par value $0.001 per share, as additional shares of 7.875% Series B Preferred Stock, thereby increasing the aggregate number of shares of preferred stock designated as Series B Preferred Stock to 17,970 shares. Shares designated as Series B Preferred Stock but unissued totaled 9,587 at December 31, 2019. On January 28, 2020, we filed Articles Supplementary with the Department to designate 10,000 shares of the Company’s authorized preferred stock, par value $0.001 per share, as shares of 7.00% Series C Preferred Stock with the powers, designations, preferences and other rights as set forth therein. At December 31, 2020, a total of 31,617 shares of our authorized preferred stock remained available for designation as future series. Called for Redemption 8.250% Series A Cumulative Preferred Stock,“Series A Preferred Stock” On June 25, 2019, the Company mailed a notice of full redemption of all 2,181 issued and outstanding shares of its Series A Preferred Stock ($25.00 liquidation preference per share) to the holders of record of its Series A Preferred Stock as of June 14, 2019. Pursuant to the redemption, each share of Series A Preferred Stock was canceled and represented solely the right to receive cash in the amount of $25.00 per share of Series A Preferred Stock on July 26, 2019. Pursuant to the terms of the Series A Preferred Stock, holders of record of the Series A Preferred Stock on July 15, 2019 received the full monthly dividend for July 2019. The final dividend amount of $375 was paid on July 29, 2019 and was recorded as other expense in our consolidated statements of operations. 7.875% Series B Cumulative Preferred Stock, “Series B Preferred Stock” On January 24, 2020, the Company mailed a notice of full redemption of all 8,383 issued and outstanding shares of its Series B Preferred Stock ($25.00 liquidation preference per share) to the holders of record of its Series B Preferred Stock as of January 13, 2020. Pursuant to the redemption, each share of Series B Preferred Stock was canceled and represented solely the right to receive cash in the amount of $25.00 per share of Series B Preferred Stock on February 27, 2020. Pursuant to the terms of the Series B Preferred Stock, holders of record of the Series B Preferred Stock on February 15, 2020 received the full monthly dividend for February 2020. The final dividend amount of $1,375 was paid on February 27, 2020 and was recorded as other expense in our consolidated statements of operations. At December 31, 2019, we had 8,383 shares of Series B Preferred Stock issued and outstanding with a par value of $0.001 per share and a liquidation preference of $25.00 per share, or $209,583 in the aggregate. Shares designated as Series B Preferred Stock but unissued totaled 9,587 at December 31, 2019. At December 31, 2019, there were no accrued or unpaid dividends on the Series B Preferred Stock. On March 2, 2020, we terminated the Equity Sales Agreement (the “Preferred B ATM Sales Agreement”) with BUCKLER, and B. Riley FBR, Inc., as sales agents, relating to an "at-the-market" offering program for our Series B Preferred Stock, dated June 24, 2019. The Preferred B ATM Sales Agreement allowed us to offer and sell, over a period of time and from time to time, up to 9,000 shares of our Series B Preferred Stock. At the date of termination, we sold 1,914 shares under this agreement for proceeds of $47,306, net of issuance costs and commissions of approximately $689. We did not incur any termination penalties as a result of this termination. On March 4, 2020, we terminated the 2019 Series B Preferred Stock Dividend Reinvestment and Stock Purchase Plan (the “2019 Plan”) relating to the offer and sale of up to 2,500 shares of our Series B Preferred Stock pursuant to the terms of the 2019 Plan (the “DRIP Offering”) dated June 24, 2019. The 2019 Plan permitted (i) current holders of our Series B Preferred Stock to reinvest all or a portion of the cash dividends on their shares of Series B Preferred Stock into shares of Series B Preferred Stock and to separately purchase additional shares of Series B Preferred Stock and (ii) other interested investors to purchase shares of Series B Preferred Stock. At the date of termination, we issued sixteen shares under the DRIP Offering. Issued and Outstanding Series C Cumulative Redeemable Preferred Stock "Series C Preferred Stock" At December 31, 2020, we had 5,347 shares of Series C Preferred Stock issued and outstanding with a par value of $0.001 per share and a liquidation preference of $25.00 per share, or $133,675 in the aggregate. Shares designated as Series C Preferred Stock but unissued totaled 4,653 at December 31, 2020. At December 31, 2020, there were no accrued or unpaid dividends on the Series C Preferred Stock. On January 23, 2020, the Company and ACM, entered into an Underwriting Agreement (the “Underwriting Agreement”) with B. Riley FBR, Inc., as representative of the several underwriters named therein (collectively, the “Underwriters”), including, but not limited to, BUCKLER, with respect to (i) the sale by the Company of 3,000 shares (the “Firm Shares”) of the Company’s new 7.00% Series C Preferred Stock ($25.00 liquidation preference per share), $0.001 par value, to the Underwriters with an offering price to the public of $25.00 per share, and (ii) the grant by the Company to the Underwriters of an option to purchase all or part of 450 additional shares of the Series C Preferred Stock during the 30-day period following the execution of the Underwriting Agreement with the same offering price per share to the public to cover over-allotments. On January 24, 2020, the Underwriters exercised the option to purchase all 450 additional shares of the Series C Preferred Stock. On January 28, 2020, the Company completed the sale of 3,450 total shares. Total proceeds were $83,282, net of issuance costs and commissions of $2,968. On January 29, 2020, the Company entered into an Equity Sales Agreement with B. Riley FBR, Inc. and BUCKLER, as sales agents (individually and collectively, the “Agents’), and ACM, pursuant to which the Company may offer and sell, over a period of time and from time to time, through one of more of the Agents, as the Company’s agents, up to 6,550 of Series C Preferred Stock. The Equity Sales Agreement relates to a proposed “at-the-market” offering. The Company intends to use the net proceeds from the offering as a portion of the funds used to redeem 100% of the outstanding Series C Preferred Stock as described above. During the year ended December 31, 2020, we sold 1,897 shares under this agreement for proceeds of $46,856, net of issuance costs and commissions of approximately $726. Common Stock At December 31, 2020 and December 31, 2019, we were authorized to issue up to 125,000 shares of common stock, par value $0.001 per share, with such designations, voting and other rights and preferences as may be determined from time to time by our Board. We had 65,290 shares of common stock issued and outstanding at December 31, 2020 and 58,877 shares of common stock issued and outstanding at December 31, 2019. On February 15, 2019, we entered into an Equity Sales Agreement (the “Common stock ATM Sales Agreement”) with BUCKLER, JMP Securities LLC and Ladenburg Thalmann & Co. Inc., as sales agents, relating to the shares of our common stock. On April 3, 2020, the Common stock ATM Sales Agreement was amended to add B. Riley, FBR, Inc. as a sales agent. On May 4, 2020 the Common stock ATM Sales Agreement was further amended to increase the number of shares available for sale pursuant to the terms of the Common Stock ATM Sales Agreement. In accordance with the terms of the Common Stock ATM Sales agreement, as amended, we may offer and sell over a period of time and from time to time, up to 17,000 shares of our common stock par value $0.001 per share. The Common stock ATM Sales Agreement relates to an "at-the-market" offering program. Under the agreement, we will pay the agent designated to sell our shares, an aggregate commission of up to 2.0% of the gross sales price per share of our common stock sold through the designated agent, under the agreement. During the year ended December 31, 2020, we sold 6,287 shares under this agreement for proceeds of $54,575, net of issuance costs and commissions of approximately $954. See Note 15 - Related Party Transactions for discussion of additional transactions with BUCKLER. Common Stock Repurchased At December 31, 2020 and December 31, 2019, there were 8,210 and 8,250 authorized shares remaining under the current repurchase authorization. Under the Repurchase Program, shares may be purchased in the open market, including block trades, through privately negotiated transactions, or pursuant to a trading plan separately adopted in the future. The timing, manner, price and amount of any repurchases will be at our discretion, subject to the requirements of the Exchange Act of 1934, as amended, and related rules. We are not required to repurchase any shares under the Repurchase Program and it may be modified, suspended or terminated at any time for any reason. We do not intend to purchase shares from our Board or other affiliates. Under Maryland law, such repurchased shares are treated as authorized but unissued. Equity Capital Raising Activities The following tables present our equity transactions for the years ended December 31, 2020 , December 31, 2019 and December 31, 2018. Transaction Type Completion Date Number of Shares Per Share price (1) Net Proceeds December 31, 2020 Preferred C Underwritten Offering January 28, 2020 3,450 $ 24.14 $ 83,282 Preferred C ATM Sales Agreement January 30, 2020 - December 23, 2020 1,897 $ 24.70 $ 46,856 Common Stock ATM Sales Agreement April 7, 2020 - December 15 2020 6,287 $ 8.68 $ 54,575 Common stock repurchases, net February 26, 2020 - March 3, 2020 (40) $ 19.42 $ (777) December 31, 2019 Preferred B ATM Sales Agreement June 6, 2019-June 19, 2019 100 $ 24.81 $ 2,489 Preferred B ATM Sales Agreement June 25, 2019-December 31, 2019 1,914 $ 24.74 $ 47,306 Common Stock ATM Sales Agreement January 4, 2019-January 11, 2019 884 $ 20.98 $ 18,540 January Public Offering January 17, 2019 6,900 $ 20.00 $ 137,946 February Public Offering February 22, 2019-February 27, 2019 8,280 $ 19.98 $ 165,374 Common stock repurchases May 31, 2019-December 31, 2019 (1,000) $ 17.77 $ (17,768) December 31, 2018 Series B Preferred equity distribution agreement January 2, 2018-January 26, 2018 107 $ 24.62 $ 2,632 DRIP August 21, 2018-December 10, 2018 840 $ 22.61 $ 19,001 Common stock ATM Sales Agreement December 11, 2018-December 19, 2018 883 $ 21.53 $ 19,013 (1) Weighted average price Dividends The following table presents our Series A Preferred Stock dividend transactions prior to full redemption for the year ended December 31, 2019. The table below does not include the final dividend amount of $375 that was paid on July 29, 2019 to holders of record on July 15, 2019. This amount was recorded in other expense in our consolidated statements of operations. 2019 Record Date Payment Date Rate per Series A Preferred Share Aggregate January 15, 2019 January 28, 2019 $ 0.17 374.8 February 15, 2019 February 27, 2019 $ 0.17 374.8 March 15, 2019 March 27, 2019 $ 0.17 374.8 April 15, 2019 April 29, 2019 $ 0.17 374.8 May 15, 2019 May 28, 2019 $ 0.17 374.8 June 15, 2019 June 27, 2019 $ 0.17 374.8 Total dividends paid $ 2,249 The following tables present our Series A Preferred Stock dividend transactions for the year ended December 31, 2018. 2018 Record Date Payment Date Rate per Series A Preferred Share Aggregate January 15, 2018 January 29, 2018 $ 0.17 $ 374.8 February 15, 2018 February 27, 2018 $ 0.17 374.8 March 15, 2018 March 27, 2018 $ 0.17 374.8 April 15, 2018 April 27, 2018 $ 0.17 374.8 May 15, 2018 May 29, 2018 $ 0.17 374.8 June 15, 2018 June 27, 2018 $ 0.17 374.8 July 15, 2018 July 27, 2018 $ 0.17 374.8 August 15, 2018 August 27, 2018 $ 0.17 374.8 September 15, 2018 September 27, 2018 $ 0.17 374.8 October 15, 2018 October 29, 2018 $ 0.17 374.8 November 15, 2018 November 27, 2018 $ 0.17 374.8 December 15, 2018 December 27, 2018 $ 0.17 374.8 Total dividends paid $ 4,498 The following table presents our Series B Preferred Stock dividend transactions prior to full redemption. The table below does not include the final dividend amount of $1,375 that was paid on February 27, 2020 to holders of record on February 15, 2020. This amount was recorded in other expense in our consolidated statements of operations. 2020 Record Date Payment Date Rate per Series B Preferred Share Aggregate January 15, 2020 January 27, 2020 $ 0.16 $ 1,375 The following table present our Series B Preferred Stock dividend transactions for the years ended December 31, 2019 and December 31, 2018. 2019 Record Date Payment Date Rate per Series B Preferred Share Aggregate January 15, 2019 January 28, 2019 $ 0.16 1,045 February 15, 2019 February 27, 2019 $ 0.16 1,045 March 15, 2019 March 27, 2019 $ 0.16 1,045 April 15, 2019 April 29, 2019 $ 0.16 1,045 May 15, 2019 May 28, 2019 $ 0.16 1,045 June 15, 2019 June 27, 2019 $ 0.16 1,059 July 15, 2019 July 29, 2019 $ 0.16 1,100 August 15, 2019 August 27, 2019 $ 0.16 1,142 September 15, 2019 September 27, 2019 $ 0.16 1,168 October 15, 2019 October 28, 2019 $ 0.16 1,190 November 15, 2019 November 27, 2019 $ 0.16 1,210 December 15, 2019 December 27, 2019 $ 0.16 1,291 Total dividends paid $ 13,385 2018 Record Date Payment Date Rate per Series B Preferred Share Aggregate January 15, 2018 January 29, 2018 $ 0.16 $ 1,039 February 15, 2018 February 27, 2018 $ 0.16 1,045 March 15, 2018 March 27, 2018 $ 0.16 1,045 April 15, 2018 April 27, 2018 $ 0.16 1,045 May 15, 2018 May 29, 2018 $ 0.16 1,045 June 15, 2018 June 27, 2018 $ 0.16 1,045 July 15, 2018 July 27, 2018 $ 0.16 1,045 August 15, 2018 August 27, 2018 $ 0.16 1,045 September 15, 2018 September 27, 2018 $ 0.16 1,045 October 15, 2018 October 29, 2018 $ 0.16 1,045 November 15, 2018 November 27, 2018 $ 0.16 1,045 December 15, 2018 December 27, 2018 $ 0.16 1,045 Total dividends paid $ 12,534 The following table presents our Series C Preferred Stock dividend transactions for the year ended December 31, 2020. 2020 Record Date Payment Date Rate per Series C Preferred Share Aggregate February 15, 2020 February 27, 2020 $ 0.14583 $ 678.1 March 15, 2020 March 27, 2020 $ 0.14583 773.4 April 15, 2020 April 27, 2020 $ 0.14583 773.4 May 15, 2020 May 27, 2020 $ 0.14583 773.4 June 15, 2020 June 29, 2020 $ 0.14583 773.4 July 15, 2020 July 27, 2020 $ 0.14583 773.4 August 15, 2020 August 27, 2020 $ 0.14583 773.4 September 15, 2020 September 28, 2020 $ 0.14583 773.4 October 15, 2020 October 27, 2020 $ 0.14583 773.4 November 15, 2020 November 27, 2020 $ 0.14583 773.4 December 15, 2020 December 28, 2020 $ 0.14583 773.4 Total dividends paid $ 8,412 The following tables present our common stock dividend transactions for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. 2020 Record Date Payment Date Rate per common share Aggregate January 15, 2020 January 30, 2020 $ 0.17 $ 10,126 February 14, 2020 February 27, 2020 $ 0.17 10,131 March 16, 2020 March 27, 2020 $ 0.17 10,120 June 15, 2020 June 29, 2020 $ 0.09 5,876 July 15, 2020 July 30, 2020 $ 0.10 6,531 August 17, 2020 August 28, 2020 $ 0.10 6,530 September 15, 2020 September 29, 2020 $ 0.10 6,529 October 15, 2020 October 29, 2020 $ 0.10 6,531 November 16, 2020 November 27, 2020 $ 0.10 6,531 December 15, 2020 December 29, 2020 $ 0.10 6,581 Total dividends paid $ 75,486 2019 Record Date Payment Date Rate per common share Aggregate January 15, 2019 January 28, 2019 $ 0.19 $ 8,540 February 15, 2019 February 28, 2019 $ 0.19 9,851 March 15, 2019 March 27, 2019 $ 0.19 11,423 April 15, 2019 April 29, 2019 $ 0.19 11,424 May 15, 2019 May 28, 2019 $ 0.19 11,424 June 17, 2019 June 27, 2019 $ 0.19 11,350 July 16, 2019 July 29, 2019 $ 0.17 10,114 August 15, 2019 August 27, 2019 $ 0.17 10,099 September 16, 2019 September 27, 2019 $ 0.17 10,075 October 15, 2019 October 28, 2019 $ 0.17 10,059 November 15, 2019 November 27, 2019 $ 0.17 10,059 December 16, 2019 December 27, 2019 $ 0.17 10,059 Total dividends paid $ 124,477 2018 Record Date Payment Date Rate per common share Aggregate January 16, 2018 January 29, 2018 $ 0.19 $ 8,046 February 15, 2018 February 27, 2018 $ 0.19 8,046 March 15, 2018 March 28, 2018 $ 0.19 8,045 April 13, 2018 April 27, 2018 $ 0.19 8,046 May 15, 2018 May 30, 2018 $ 0.19 8,046 June 15, 2018 June 28, 2018 $ 0.19 8,045 July 16, 2018 July 27, 2018 $ 0.19 8,045 August 15, 2018 August 28, 2018 $ 0.19 8,045 September 17, 2018 September 27, 2018 $ 0.19 8,117 October 15, 2018 October 29, 2018 $ 0.19 8,118 November 15, 2018 November 27, 2018 $ 0.19 8,118 December 17, 2018 December 27, 2018 $ 0.19 8,307 Total dividends paid $ 97,024

Net Income (Loss) per Common Sh

Net Income (Loss) per Common Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Income (Loss) per Common Share	Note 12 - Net Income (Loss) per Common Share The following table presents a reconciliation of net loss and the shares used in calculating weighted average basic and diluted earnings per common share for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 Net Loss $ (215,112) $ (249,905) $ (105,966) Less: Preferred dividends (9,787) (15,634) (17,032) Net Loss related to common stockholders $ (224,899) $ (265,539) $ (122,998) Weighted average common shares outstanding – basic 63,070 57,833 42,128 Add: Effect of dilutive non-vested awards, assumed vested — — — Weighted average common shares outstanding – diluted 63,070 57,833 42,128 For the years ended December 31, 2020, December 31, 2019 and December 31, 2018, 496, 247 and 360, respectively, of potentially dilutive non-vested awards outstanding were excluded from the computation of diluted Net Loss related to common stockholders because to have included them would have been anti-dilutive for the period. Note 13 - Comprehensive Income (Loss) per Common Share The following table presents a reconciliation of comprehensive net income (loss) and the shares used in calculating weighted average basic and diluted comprehensive income (loss) per common share for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 Comprehensive Income (Loss) $ (391,554) $ 149,438 $ (129,725) Less: Preferred dividends (9,787) (15,634) (17,032) Comprehensive Income (Loss) available (related) to common stockholders $ (401,341) $ 133,804 $ (146,757) Net Comprehensive Income (Loss) per share available (related) to common stockholders: Basic $ (6.36) $ 2.31 $ (3.48) Diluted $ (6.36) $ 2.30 $ (3.48) Weighted average common shares outstanding: Basic 63,070 57,833 42,128 Add: Effect of dilutive non-vested awards, assumed vested — 247 — Diluted 63,070 58,080 42,128

Comprehensive Income (Loss) per

Comprehensive Income (Loss) per Common Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Comprehensive Income (Loss) per Common Share	Note 12 - Net Income (Loss) per Common Share The following table presents a reconciliation of net loss and the shares used in calculating weighted average basic and diluted earnings per common share for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 Net Loss $ (215,112) $ (249,905) $ (105,966) Less: Preferred dividends (9,787) (15,634) (17,032) Net Loss related to common stockholders $ (224,899) $ (265,539) $ (122,998) Weighted average common shares outstanding – basic 63,070 57,833 42,128 Add: Effect of dilutive non-vested awards, assumed vested — — — Weighted average common shares outstanding – diluted 63,070 57,833 42,128 For the years ended December 31, 2020, December 31, 2019 and December 31, 2018, 496, 247 and 360, respectively, of potentially dilutive non-vested awards outstanding were excluded from the computation of diluted Net Loss related to common stockholders because to have included them would have been anti-dilutive for the period. Note 13 - Comprehensive Income (Loss) per Common Share The following table presents a reconciliation of comprehensive net income (loss) and the shares used in calculating weighted average basic and diluted comprehensive income (loss) per common share for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 Comprehensive Income (Loss) $ (391,554) $ 149,438 $ (129,725) Less: Preferred dividends (9,787) (15,634) (17,032) Comprehensive Income (Loss) available (related) to common stockholders $ (401,341) $ 133,804 $ (146,757) Net Comprehensive Income (Loss) per share available (related) to common stockholders: Basic $ (6.36) $ 2.31 $ (3.48) Diluted $ (6.36) $ 2.30 $ (3.48) Weighted average common shares outstanding: Basic 63,070 57,833 42,128 Add: Effect of dilutive non-vested awards, assumed vested — 247 — Diluted 63,070 58,080 42,128

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 14 - Income Taxes The following table reconciles our GAAP net loss to estimated REIT taxable income (loss) for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 GAAP net loss $ (215,112) $ (249,905) $ (105,966) Book to tax differences: TRS income (51) (147) (265) Premium amortization expense (261) — (1,132) Agency Securities, trading (19,557) — — Credit Risk and Non-Agency Securities 188,075 24,459 26,509 Interest-Only Securities — 85 318 U.S. Treasury Securities (21,357) (2,024) 6,365 Changes in interest rate contracts 268,159 375,493 (1,346) Reversal of (Gain) Loss on Security sales (143,877) (9,611) 152,950 Credit loss expense/OTTI 1,012 — 12,090 Amortization of deferred hedging costs (152,092) (69,302) (56,378) Series A Cumulative Preferred Stock dividend- Called for redemption — 375 — Series B Cumulative Preferred Stock dividend- Called for redemption 1,375 — — Other 1,544 18 16 Estimated taxable income (loss) $ (92,142) $ 69,441 $ 33,161 Interest rate contracts are treated as hedging transactions for U. S. federal income tax purposes. Unrealized gains and losses on open interest rate contracts are not included in the determination of REIT taxable income. Realized gains and losses on interest rate contracts terminated before their maturity are deferred and amortized over the remainder of the original term of the contract for REIT taxable income. At December 31, 2020, we had approximately $717,000 in interest rate swap expense amortizing through the year 2029. Net capital losses realized Amount Available to offset capital gains though 2016 (31,204) 2021 2017 (7,375) 2022 2018 (216,634) 2023 The Company's subsidiary, ARMOUR TRS, Inc. has made an election as a taxable REIT subsidiary (“TRS”). As such, the TRS is taxable as a domestic C corporation and subject to federal, state, and local income taxes based upon its taxable income. During the years ended December 31, 2020 and December 31, 2019, we recorded $36 and $25, respectively of income tax expense attributable to our TRS. The aggregate tax basis of our assets and liabilities was greater than our total Stockholders’ Equity at December 31, 2020, by approximately $323,071, or approximately $4.95 per common share (based on the 65,290 common shares then outstanding). We are required and intend to timely distribute substantially all of our REIT taxable income in order to maintain our REIT status under the Code. Total dividend payments to stockholders for the year ended December 31, 2020, were $86,648 (including the final dividend on the Series B Preferred Stock, called for redemption of $1,375 paid on February 27, 2020 to holders of record on February 15, 2020). Total dividend payments to stockholders for the year ended December 31, 2019, were $140,486 (including the final dividend on the Series A Preferred Stock, called for redemption of $375 paid on July 29, 2019 to holders of record on July 15, 2019). Total dividend payments to stockholders for the year ended December 31, 2018 were $114,056. Our estimated REIT taxable income (loss) available for distribution as dividends was $(92,142), $69,441 and $33,161 for the years ended December 31, 2020, December 31, 2019 and December 31, 2018, respectively. Our REIT taxable income and dividend requirements to maintain our REIT status are determined on an annual basis. Dividends paid in excess of current tax earnings and profits for the year will generally not be taxable to common stockholders. The portion of the dividends on our common stock which represented non-taxable return of capital was approximately 100.0% in 2020, 56.8% in 2019 and 83.2% in 2018. Our management is responsible for determining whether tax positions taken by us are more likely than not to be sustained on their merits. We have no material unrecognized tax benefits or material uncertain tax positions.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Note 15 - Related Party Transactions ACM Management: The Company is managed by ACM, pursuant to management agreements with ARMOUR and JAVELIN. All of our executive officers are also employees of ACM. ACM manages our day-to-day operations, subject to the direction and oversight of the Board. The ARMOUR management agreement runs through June 18, 2027 and is thereafter automatically renewed for an additional five-year term unless terminated under certain circumstances. The JAVELIN management agreement renewed on October 5, 2017, for a one-year period, with the annual management fee thereunder reduced to one dollar for the entirety of the renewal term. It will automatically renew for successive one-year terms unless terminated under certain circumstances. Either party must provide 180 days prior written notice of any such termination. Under the terms of the management agreements, ACM is responsible for costs incident to the performance of its duties, such as compensation of its employees and various overhead expenses. ACM is responsible for the following primary roles: • Advising us with respect to, arranging for and managing the acquisition, financing, management and disposition of, elements of our investment portfolio; • Evaluating the duration risk and prepayment risk within the investment portfolio and arranging borrowing and hedging strategies; • Coordinating capital raising activities; • Advising us on the formulation and implementation of operating strategies and policies, arranging for the acquisition of assets, monitoring the performance of those assets and providing administrative and managerial services in connection with our day-to-day operations; and • Providing executive and administrative personnel, office space and other appropriate services required in rendering management services to us. The following table reconciles the fees incurred in accordance with the ARMOUR management agreement for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. ACM began waiving 40% of its management fee during the second quarter of 2020. On January 13, 2021, ACM notified ARMOUR that it intended to adjust the fee waiver to the rate of $2,400 for the first quarter of 2021 and $800 per month thereafter until further notice (see Note 16 - Subsequent Events ). For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 ARMOUR management fees $ 29,580 $ 29,513 $ 27,190 Less management fees waived (8,855) — — Total Management fee expense $ 20,725 $ 29,513 $ 27,190 In accordance with the JAVELIN management agreement, we paid management fees of one dollar for each of the years ended December 31, 2020 and December 31, 2019 and December 31, 2018. We are required to take actions as may be reasonably required to permit and enable ACM to carry out its duties and obligations. We are also responsible for any costs and expenses that ACM incurred solely on our behalf other than the various overhead expenses specified in the terms of the management agreements. For the years ended December 31, 2020, December 31, 2019 and December 31, 2018 we reimbursed ACM $157, $114 and $206, respectively for other expenses incurred on our behalf. In 2013, 2017 and 2020, we elected to grant restricted stock unit awards to our executive officers and other ACM employees through ACM that vest over various periods through 2027. In November 2017 and January 2020, we elected to grant restricted stock unit awards to the Board. We recognized stock based compensation expense of $515, $348 and $436 for the years ended, December 31, 2020, December 31, 2019 and December 31, 2018, respectively. BUCKLER In March 2017, we contributed $352 for a 10% ownership interest in BUCKLER. The investment is included in prepaid and other assets in our consolidated balance sheet and is accounted for using the equity method as BUCKLER maintains specific ownership accounts. The value of the investment was $634 at December 31, 2020 and $381 at December 31, 2019 reflecting our total investment plus our share of BUCKLER’s operating results, in accordance with the terms of the operating agreement of BUCKLER that our independent directors negotiated. The primary purpose of our investment in BUCKLER is to facilitate our access to repurchase financing on potentially attractive terms (considering rate, term, size, haircut, relationship and funding commitment) compared to other suitable repurchase financing counterparties. Our operating agreement with BUCKLER contains certain provisions to benefit and protect the Company, including (1) sharing in any (a) defined profits realized by BUCKLER from the anticipated financing spreads resulting from repurchase financing facilitated by BUCKLER, and (b) distributions from BUCKLER to its members of net cash receipts, and (2) the realization of anticipated savings from reduced clearing, brokerage, trading and administrative fees. In addition, the independent directors of the Company, must approve in their sole discretion, any third-party business engaged by BUCKLER and may cause BUCKLER to wind up and dissolve and promptly return certain subordinated loans we provide to BUCKLER as regulatory capital (as described more fully below) if the independent directors reasonably determine that BUCKLER’s ability to provide attractive securities transactions for the Company is materially adversely affected. For the year ended December 31, 2020, we earned $1,408 from BUCKLER as an allocated share of Financing Gross Profit for a reduction of interest on repurchase agreements charged to the Company. Financing Gross Profit is defined in the operating agreement, subject to a contractually required reduction in our share of the Financing Gross Profit of $306 per annum until the end of the first quarter of 2021 (see Note 11 - Stockholders' Equity for discussion of equity transactions with BUCKLER). We previously entered into three subordinated loan agreements with BUCKLER, totaling $105,000. On March 18, 2019, these three subordinated loan agreements were consolidated into one loan of $105,000, maturing on April 1, 2022, with automatic renewals. During the second quarter of 2020, we agreed to extend the maturity of the loan to May 1, 2025. BUCKLER may, at its option after obtaining the approval of the Financial Industry Regulatory Authority, repay all or a portion of the principal amount of the loan. The loan has a stated interest rate of zero, plus additional interest payable to the Company in an amount equal to the amount of interest earned by BUCKLER on the investment of the loan proceeds, generally in government securities funds. For the years ended December 31, 2020, December 31, 2019 and December 31, 2018, the Company earned $333, $1,886 and $2,019 in interest on this loan. The table below summarizes other transactions with BUCKLER as of and for the years ended December 31, 2020 and December 31, 2019. Transactions with BUCKLER December 31, 2020 December 31, 2019 Repurchase agreements (1) $ 2,998,111 $ 5,107,101 Interest on repurchase agreements $ 38,663 $ 120,090 Collateral posted on repurchase agreements $ 3,117,929 $ 5,341,487

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	Note 16 - Subsequent Events Except as set forth below, no subsequent events were identified through the date of issuance. Coronavirus pandemic ("COVID-19") COVID-19 continues to have a real-time impact on all business sectors. The extent of the ultimate impact of COVID-19 on the Company's operational and financial performance will depend on various developments, including the duration of the outbreak and the spread of the virus and the federal government's and states' future responses to the virus, which cannot be reasonably predicted at this time. While the Company is not able to estimate the future impact of COVID-19 at this time, it could continue to materially affect the Company’s future financial and operational results. ACM Management Agreement On April 30, 2020, ACM notified ARMOUR that ACM was voluntarily waiving a portion of the Base Management Fee due and payable to ACM pursuant to the Seventh Amended and Restated Management Agreement, effective as of November 17, 2017 (as further amended and restated on July 21, 2020, the “Agreement”), until further notice. This previously disclosed voluntary waiver was deemed prudent by ACM to maintain a competitive cost structure for ARMOUR considering the COVID-19 related decline in the stockholders’ equity of ARMOUR. In early January 2021, ACM reviewed (and will continue to review quarterly) the level of such fee waiver considering current economic circumstances and noted that from May 1, 2020 to December 31, 2020, the stockholders’ equity of ARMOUR has increased (before issuance of additional shares), resulting in a partial recovery of the COVID-19 related decline. On January 13, 2021, ACM notified ARMOUR that it intended to adjust the fee waiver to the rate of $2,400 for the first quarter of 2021 and $800 per month thereafter until ACM provides further notice to ARMOUR. ACM may terminate this waiver for any month by providing notice to ARMOUR on or before the 25th day of the preceding month. This waiver does not constitute a waiver of any other amounts due to ACM from ARMOUR under the Agreement or otherwise, including but not limited to any expense reimbursements, any amounts calculated by reference to the contractual Base Management Fee, or any awards under the Second Amended and Restated 2009 Stock Incentive Plan. Series C Preferred Stock On January 27, 2021, a cash dividend of $0.14583 per outstanding share of Series C Preferred Stock, or $780 in the aggregate, was paid to holders of record on January 15, 2021. We have also declared cash dividends of $0.14583 payable February 26, 2021 and March 29, 2021 to holders of record on February 15, 2021 and March 15, 2021, respectively. Between January 19, 2021 and February 16, 2021, we issued 434 shares under our Preferred C ATM Sales Agreement for proceeds of $10,594, net of issuance costs and commissions of $108. Common Stock On January 28, 2021, a cash dividend of $0.10 per outstanding common share, or $6,646 in the aggregate, was paid to holders of record on January 15, 2021. We have also declared cash dividends of $0.10 per outstanding common share payable February 26, 2021 to holders of record on February 16, 2021 and payable March 29, 2021 to holders of record on March 15, 2021.

Quarterly Financial Data (unaud

Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (unaudited)	Note 17 - Quarterly Financial Data (unaudited) The following tables are a comparative breakdown of our unaudited quarterly financial results for the immediately preceding eight quarters. Quarter Ended March 31, June 30, September 30, December 31, Agency Securities, net of amortization of premium and fees $ 79,776 $ 23,648 $ 25,188 $ 22,594 Credit Risk and Non-Agency Securities, including discount accretion 12,355 4,873 518 — U.S. Treasury Securities 469 — — — BUCKLER Subordinated loan 258 29 24 22 Interest expense- repurchase agreements (51,520) (5,389) (2,954) (3,076) Interest expense- U.S. Treasury Securities sold short — (32) — — Net Interest Income $ 41,338 $ 23,129 $ 22,776 $ 19,540 Realized gain (loss) on sale of Agency Securities (reclassified from Other comprehensive income (loss)) 93,325 36,008 9,468 5,076 Credit loss expense (1,012) — — — Gain on Agency Securities, trading — 7,911 12,149 (503) Gain (Loss) on Credit Risk and Non-Agency Securities (183,111) 190 (6,633) (1) Gain (loss) U.S. Treasury Securities 21,771 — — — Loss on short sale of U.S. Treasury Securities — (414) — — Realized gain (loss) on derivatives (1) (235,148) (180,567) 20,866 16,641 Unrealized gain (loss) on derivatives (133,887) 173,325 6,866 47,751 Expenses (9,935) (10,781) (10,059) (10,046) Management fees waived — 2,947 2,953 2,955 Net Income (Loss) $ (406,659) $ 51,748 $ 58,386 $ 81,413 Dividends declared on preferred stock (2,827) (2,320) (2,320) (2,320) Net Income (Loss) available (related) to common stockholders $ (409,486) $ 49,428 $ 56,066 79,093 Net income (loss) available (related) per share to common stockholders – Basic $ (6.95) $ 0.78 $ 0.87 $ 1.22 Net income (loss) available (related) per share to common stockholders – Diluted $ (6.95) $ 0.77 $ 0.86 $ 1.21 Dividends declared per common share $ 0.51 $ 0.09 $ 0.30 $ 0.30 Weighted average common shares outstanding – Basic 58,884 63,741 64,724 64,895 Weighted average common shares outstanding – Diluted 58,884 64,340 65,272 65,392 Quarter Ended March 31, June 30, September 30, December 31, Agency Securities, net of amortization of premium and fees $ 79,832 $ 113,438 $ 102,134 $ 87,407 Credit Risk and Non-Agency Securities, including discount accretion 13,592 13,383 13,158 12,785 Interest-Only Securities 345 251 — — U.S. Treasury Securities 482 744 128 — BUCKLER Subordinated loan 539 544 479 324 Interest expense- repurchase agreements (60,978) (87,504) (80,293) (59,454) Net Interest Income $ 33,812 $ 40,856 $ 35,606 $ 41,062 Realized loss on sale of Agency Securities (reclassified from Other comprehensive income (loss)) (2,910) (44) 4,569 7,996 Gain (Loss) on Credit Risk and Non-Agency Securities 496 (17,699) (8,842) 1,650 Gain (Loss) on Interest-Only Securities (368) 490 — — Gain (loss) U.S. Treasury Securities (693) 3,453 (736) — Realized gain (loss) on derivatives (1) (22,131) (92,990) (85,076) (13,799) Unrealized gain (loss) on derivatives (113,067) (107,304) 3,845 80,399 Expenses (9,520) (10,012) (10,321) (8,627) Net Income (Loss) $ (114,381) $ (183,250) $ (60,955) $ 108,681 Dividends declared on preferred stock (4,259) (4,274) (3,410) (3,691) Net Income (Loss) available (related) to common stockholders $ (118,640) $ (187,524) $ (64,365) $ 104,990 Net income (loss) available (related) per share to common stockholders – Basic $ (2.21) $ (3.14) $ (1.09) $ 1.78 Net income (loss) available (related) per share to common stockholders – Diluted $ (2.21) $ (3.14) $ (1.09) $ 1.78 Dividends declared per common share $ 0.57 $ 0.57 $ 0.51 $ 0.51 Weighted average common shares outstanding – Basic 53,630 59,654 59,077 58,902 Weighted average common shares outstanding – Diluted 53,630 59,654 59,077 59,149 (1) Interest expense related to our interest rate swap contracts is recorded in realized loss on derivatives on the consolidated statements of operations.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the U.S. (“GAAP”). The consolidated financial statements include the accounts of ARMOUR Residential REIT, Inc. and its subsidiaries. All intercompany accounts and transactions have been eliminated. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Significant estimates affecting the accompanying consolidated financial statements include the valuation of MBS, including an assessment of the allowance for credit losses, and derivative instruments.
Cash	Cash Cash includes cash on deposit with financial institutions. We may maintain deposits in federally insured financial institutions in excess of federally insured limits. However, management believes we are not exposed to significant credit risk due to the financial position and creditworthiness of the depository institutions in which those deposits are held.
Cash Collateral Posted To/By Counterparties	Cash Collateral Posted To/By Counterparties Cash collateral posted to/by counterparties represents cash posted by us to counterparties or posted by counterparties to us as collateral. Cash collateral posted to/by counterparties may include collateral for interest rate swap contracts (including swaptions and basis swap contracts), and repurchase agreements on our MBS and our Agency Securities purchased or sold on a to-be-announced basis ("TBA Agency Securities").
Investments in Securities, at Fair Value	Investments in Securities, at Fair Value Our investments in securities are generally classified as either available for sale or trading securities. Management determines the appropriate classifications of the securities at the time they are acquired and evaluates the appropriateness of such classifications at each balance sheet date. Available for Sale Securities represent investments that we intend to hold for extended periods of time and are reported at their estimated fair values with unrealized gains and losses excluded from earnings and reported as part of the consolidated statements of comprehensive income (loss). Trading Securities
Receivables and Payables for Unsettled Sales and Purchases	Receivables and Payables for Unsettled Sales and Purchases     We account for purchases and sales of securities on the trade date, including purchases and sales for forward settlement. Receivables and payables for unsettled trades represent the agreed trade price multiplied by the outstanding balance of the securities at the balance sheet date.
Accrued Interest Receivable and Payable	Accrued Interest Receivable and Payable
Repurchase Agreements	Repurchase Agreements We finance the acquisition of the majority of our MBS through the use of repurchase agreements. Our repurchase agreements are secured by our MBS and bear interest rates that have historically moved in close relationship to the Federal Funds Rate and short-term London Interbank Offered Rate ("LIBOR"). Under these repurchase agreements, we sell MBS to a lender and agree to repurchase the same MBS in the future for a price that is higher than the original sales price. The difference between the sales price that we receive and the repurchase price that we pay represents interest paid to the lender, which accrues over the life of the repurchase agreement. A repurchase agreement operates as a financing arrangement under which we pledge our MBS as collateral to secure a loan which is equal in value to a specified percentage of the estimated fair value of the pledged collateral. We retain beneficial ownership of the pledged collateral. At the maturity of a repurchase agreement, we are required to repay the loan and concurrently receive back our pledged collateral from the lender or, with the consent of the lender, we may renew such agreement at the then prevailing interest rate. The repurchase agreements may require us to pledge additional assets to the lender in the event the estimated fair value of the existing pledged collateral declines.
Derivatives, at Fair Value	Derivatives, at Fair Value We recognize all derivatives individually as either assets or liabilities at fair value on our consolidated balance sheets. All changes in the fair values of our derivatives are reflected in our consolidated statements of operations. We designate derivatives as hedges for tax purposes and any unrealized derivative gains or losses would not affect our distributable net taxable income. These transactions may include interest rate swap contracts, interest rate swaptions and basis swap contracts.
Impairment of Assets	Impairment of Assets    We assess impairment of available for sale securities at least on a quarterly basis and more frequently when economic or market concerns warrant such evaluation. We consider an impairment if we (1) intend to sell the available for sale securities, or (2) believe it is more likely than not that we will be required to sell the securities before recovery (for example, because of liquidity requirements or contractual obligations) and a credit impairment exists where fair value is less than amortized cost. Impairment losses recognized establish a new cost basis for the related available for sale securities.
Revenue Recognition	Revenue Recognition Interest income is earned and recognized on Agency Securities based on their unpaid principal amounts and their contractual terms. Recognition of interest income commences on the settlement date of the purchase transaction and continues through the settlement date of the sale transaction. Premiums and discounts associated with the purchase of Multi-Family MBS, which are generally not subject to prepayment, are amortized or accreted into interest income over the contractual lives of the securities using a level yield method. Premiums and discounts associated with the purchase of other Agency Securities are amortized or accreted into interest income over the actual lives of the securities, reflecting actual prepayments as they occur. Purchase and sale transactions (including TBA Agency Securities) are recorded on the trade date to the extent it is probable that we will take or make timely physical delivery of the related securities. Gains or losses realized from sales of available for sale securities are reclassified into income from other comprehensive income and are determined using the specific identification method. Interest income on Credit Risk and Non-Agency Securities and Interest-Only Securities is recognized using the effective yield method over the life of the securities based on the future cash flows expected to be received. Future cash flow projections and related effective yields are determined for each security and updated quarterly. Impairment losses establish a new cost basis in the security for purposes of calculating effective yields, recognized when the fair value of a security is less than its cost basis and there has been an adverse change in the future cash flows expected to be received. Other changes in future cash flows expected to be received are recognized prospectively over the remaining life of the security. Interest income on U.S. Treasury Securities is recognized based on their unpaid principal amounts and their contractual terms. Recognition of interest income commences on the settlement date of the purchase transaction and continues through the settlement date of the sale transaction.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) refers to changes in equity during a period from transactions and other events and circumstances from non-owner sources. It includes all changes in equity during a period, except those resulting from investments by owners and distributions to owners.
Recent Accounting Pronouncements	We consider the applicability and impact of all Accounting Standards Updates ("ASU") issued by the Financial Accounting Standards Board. Those not listed below were deemed to be either not applicable, are not expected to have a significant impact on our consolidated financial statements when adopted, or did not have a significant impact on our consolidated financial statements upon adoption. Accounting Standard Description ASU 2016-13, Financial Instruments–Credit Losses (Topic 326) The standard introduces a new model for recognizing credit losses on financial instruments based on an estimate of current expected credit losses. The standard applies to (1) loans, accounts receivable, trade receivables, and other financial assets measured at amortized cost, (2) loan commitments and certain other off–balance sheet credit exposures, (3) debt securities and other financial assets measured at fair value through other comprehensive income, and (4) beneficial interests in securitized financial assets. The standard was effective for fiscal years beginning after December 15, 2019. The adoption of the standard on January 1, 2020 did not have a significant impact on the Company, since at that time we did not intend to sell our investments in available for sale Agency Securities. The Company determined that it was not more likely than not that we would be required to sell the investments before recovery of their amortized cost bases as the contractual cash flows of these federal agency mortgage backed securities are guaranteed by an agency of the U.S. government and we expected that all securities would not be settled at a price less than their amortized cost.

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table provides a summary of our assets and liabilities that are measured at fair value on a recurring basis at December 31, 2020 and December 31, 2019. December 31, 2020 (Level 1) (Level 2) (Level 3) Balance Assets at Fair Value: Agency Securities $ — $ 5,178,322 $ — $ 5,178,322 Derivatives $ — $ 54,686 $ — $ 54,686 Liabilities at Fair Value: Derivatives $ — $ 1,217 $ — $ 1,217 December 31, 2019 (Level 1) (Level 2) (Level 3) Balance Assets at Fair Value: Agency Securities $ — $ 11,941,766 $ — $ 11,941,766 Credit Risk and Non-Agency Securities $ — $ 883,601 $ — $ 883,601 Derivatives $ — $ 24,751 $ — $ 24,751 Liabilities at Fair Value: $ — Derivatives $ — $ 71,974 $ — $ 71,974

Investment In Securities (Table

Investment In Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Summary of Investment in Securities	The following tables summarize our investment in securities as of December 31, 2020 and December 31, 2019, excluding TBA Agency Securities (see Note 8 - Derivatives) . Beginning in the second quarter of 2020, we designated Agency MBS purchased as “trading securities” for financial reporting purposes, and consequently, fair value changes for these investments will be reported in net income. We anticipate continuing this designation for newly acquired Agency MBS positions because it is more representative of our results of operations insofar as the fair value changes for these securities are presented in a manner consistent with the presentation and timing of the fair value changes of our hedging instruments. Fair value changes for the legacy Agency Securities designated as available for sale will continue to be reported in other comprehensive income as required by GAAP. Available for Sale Trading Securities Agency Agency Credit Risk and Non-Agency Interest-Only U.S. Treasuries Totals December 31, 2020 Balance, December 31, 2019 $ 11,941,766 $ — $ 883,601 $ — $ — $ 12,825,367 Purchases (1) 1,768,688 3,711,961 237,928 — 4,621,776 10,340,353 Proceeds from sales (10,800,879) (158,708) (889,057) — (4,643,049) (16,491,693) Principal repayments (873,650) (343,514) (45,766) — — (1,262,930) Gains (losses) (32,565) 19,557 (189,555) — 21,357 (181,206) Credit loss expense (1,012) — — — — (1,012) Amortization/accretion (31,446) (21,876) 2,849 — (84) (50,557) Balance, December 31, 2020 $ 1,970,902 $ 3,207,420 $ — $ — $ — $ 5,178,322 Percentage of Portfolio 38.06 % 61.94 % — % — % — % 100.00 % December 31, 2019 Balance, December 31, 2018 $ 7,051,954 — $ 819,915 $ 20,623 $ 98,646 $ 7,991,138 Purchases (1) 9,130,512 — 138,767 — 1,685,058 $ 10,954,337 Sales (2,894,339) — — (18,822) (1,786,090) $ (4,699,251) Principal Repayments (1,701,406) — (53,641) — — $ (1,755,047) Losses 408,954 — (24,396) 123 2,024 $ 386,705 Amortization/accretion (53,909) — 2,956 (1,924) 362 $ (52,515) Balance, December 31, 2019 $ 11,941,766 $ — $ 883,601 $ — $ — $ 12,825,367 Percentage of Portfolio 93.11 % — % 6.89 % — % — % 100.00 % (1) Purchases include cash paid during the period, plus payable for investment securities purchased during the period as of period end.
Available-for-sale Securities in an Unrealized Gain or Loss Position	The table below presents the components of the carrying value and the unrealized gain or loss position of our available for sale securities at December 31, 2020 and December 31, 2019. Our available for sale securities had a weighted average coupon of 3.25% and 3.76% at December 31, 2020 and December 31, 2019. Agency Securities Principal Amount Amortized Cost Gross Unrealized Loss Gross Unrealized Gain Fair Value December 31, 2020 Total Fannie Mae $ 1,359,136 $ 1,397,206 $ (1) $ 159,603 $ 1,556,808 Total Freddie Mac 354,382 368,686 — 19,246 387,932 Total Ginnie Mae 25,388 25,979 (43) 226 26,162 Total $ 1,738,906 $ 1,791,871 $ (44) $ 179,075 $ 1,970,902 December 31, 2019 Total Fannie Mae $ 8,779,331 $ 8,975,140 $ (291) $ 294,937 $ 9,269,786 Total Freddie Mac 2,522,870 2,587,512 (40) 61,323 2,648,795 Total Ginnie Mae 22,504 23,641 (461) 5 23,185 Total $ 11,324,705 $ 11,586,293 $ (792) $ 356,265 $ 11,941,766
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	The following table presents the unrealized losses and estimated fair value of our available for sale securities by length of time that such securities have been in a continuous unrealized loss position at December 31, 2020 and December 31, 2019. All of our available for sale securities are issued and guaranteed by GSEs or Ginnie Mae. The GSEs have a long term credit rating of AA+. Unrealized Loss Position For: < 12 Months ≥ 12 Months Total Agency Securities Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses December 31, 2020 $ 8,811 $ (44) $ — $ — $ 8,811 $ (44) December 31, 2019 $ 2,136 $ (10) $ 43,939 $ (782) $ 46,075 $ (792)
Investments Classified by Contractual Maturity Date	The following table summarizes the weighted average lives of our available for sale securities at December 31, 2020 and December 31, 2019. December 31, 2020 December 31, 2019 Weighted Average Life of Fair Value Amortized Fair Value Amortized < 1 year $ 71 $ 72 $ — $ — ≥ 1 year and < 3 years 548,352 520,657 22,237 22,254 ≥ 3 years and < 5 years 282,739 269,716 6,542,389 6,365,623 ≥ 5 years 1,139,740 1,001,426 5,377,140 5,198,416 Total Available for Sale Securities $ 1,970,902 $ 1,791,871 $ 11,941,766 $ 11,586,293 The following table summarizes the weighted average lives of our trading securities at December 31, 2020 and December 31, 2019. December 31, 2020 December 31, 2019 Estimated Weighted Average Life of Trading Securities Fair Value Amortized Cost Fair Value Amortized Cost < 1 year $ — $ — $ — $ — ≥ 1 year and < 3 years 649,425 650,328 389,883 369,600 ≥ 3 years and < 5 years 1,522,509 1,506,035 407,656 375,030 ≥ 5 years 1,035,486 1,030,366 86,062 80,214 Total $ 3,207,420 $ 3,186,729 $ 883,601 $ 824,844
Debt Securities, Trading, and Equity Securities, FV-NI	The components of the carrying value of our trading securities at December 31, 2020 and December 31, 2019 are presented in the table below. We did not have any Credit Risk and Non-Agency Securities, U.S. Treasury Securities or Interest-Only Securities at December 31, 2020. We did not have any U.S. Treasury Securities or Interest-Only Securities at December 31, 2019. Principal Amount Amortized Cost Gross Unrealized Loss Gross Unrealized Gain Fair Value December 31, 2020 Agency Securities: Total Fannie Mae $ 2,420,828 $ 2,585,409 $ (1,441) $ 18,211 $ 2,602,179 Total Freddie Mac 570,654 601,320 (430) 4,351 605,241 Total Trading Securities $ 2,991,482 $ 3,186,729 $ (1,871) $ 22,562 $ 3,207,420 December 31, 2019 Credit Risk Transfer $ 754,729 $ 751,940 $ — $ 52,024 $ 803,964 Non-Agency Securities 93,723 72,904 (3) 6,736 79,637 Total Trading Securities $ 848,452 $ 824,844 $ (3) $ 58,760 $ 883,601

Repurchase Agreements (Tables)

Repurchase Agreements (Tables)	12 Months Ended
	Dec. 31, 2020
Disclosure of Repurchase Agreements [Abstract]
Schedule of Repurchase Agreements	The following table represents the contractual repricing regarding our repurchase agreements to finance MBS purchases at December 31, 2020 and December 31, 2019. No amounts below are subject to offsetting. Balance Weighted Average Contractual Rate Weighted Average Maturity in days Haircut (1) December 31, 2020 Agency Securities ≤ 30 days $ 3,618,255 0.23 % 15 3.12 % > 30 days to ≤ 60 days 917,810 0.23 % 45 3.20 % Total or Weighted Average $ 4,536,065 0.23 % 21 3.13 % December 31, 2019 Agency Securities ≤ 30 days $ 10,241,137 2.56 % 8 4.35 % > 30 days to ≤ 60 days 426,147 1.99 % 34 4.61 % Total or Weighted Average 10,667,284 2.54 % 9 4.36 % Credit Risk and Non-Agency Securities ≤ 30 days 687,263 2.45 % 15 16.25 % Total or Weighted Average $ 11,354,547 2.54 % 9 5.16 % (1) The Haircut represents the weighted average margin requirement, or the percentage amount by which the collateral value must exceed the loan amount.

Derivatives (Tables)

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Offsetting Assets	The following tables present information about the potential effects of netting our derivatives if we were to offset the assets and liabilities on the accompanying consolidated balance sheets. We currently present these financial instruments at their gross amounts and they are included in derivatives, at fair value on the accompanying consolidated balance sheets at December 31, 2020 and December 31, 2019. Gross Amounts Not Offset Assets Gross Amounts (1) Financial Cash Collateral Total Net December 31, 2020 Interest rate swap contracts $ 34,588 $ (866) $ (27,773) $ 5,949 TBA Agency Securities 20,098 (351) (13,942) 5,805 Totals $ 54,686 $ (1,217) $ (41,715) $ 11,754 December 31, 2019 Interest rate swap contracts $ 23,659 $ (70,290) $ 83,066 $ 36,435 TBA Agency Securities 1,092 (1,092) — — Totals $ 24,751 $ (71,382) $ 83,066 $ 36,435 (1) See Note 5, “Fair Value of Financial Instruments” for additional discussion.
Offsetting Liabilities	Gross Amounts Not Offset Liabilities Gross Amounts (1) Financial Cash Collateral Total Net December 31, 2020 Interest rate swap contracts $ (866) $ 866 $ — $ — TBA Agency Securities (351) 351 — — Totals $ (1,217) $ 1,217 $ — $ — December 31, 2019 Interest rate swap contracts $ (70,290) $ 70,290 $ — $ — TBA Agency Securities (1,684) 1,092 377 (215) Totals $ (71,974) $ 71,382 $ 377 $ (215) (1) See Note 5, “Fair Value of Financial Instruments” for additional discussion.
Derivative Instruments, Gain (Loss)	The following table represents the location and information regarding our derivatives which are included in Other Income (Loss) in the accompanying consolidated statements of operations for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. Income (Loss) Recognized For the Years Ended Derivatives Location on consolidated statements of operations December 31, 2020 December 31, 2019 December 31, 2018 Interest rate swap contracts: Realized gain (loss) Realized loss on derivatives $ (461,374) $ (237,725) $ 2,655 Interest income Realized loss on derivatives 30,076 187,899 124,714 Interest expense Realized loss on derivatives (46,069) (162,529) (124,241) Changes in fair value Unrealized gain (loss) on derivatives 81,287 (132,303) 43,755 $ (396,080) $ (344,658) $ 46,883 TBA Agency Securities: Realized gain (loss) Realized loss on derivatives 99,159 (1,641) (50,625) Changes in fair value Unrealized gain (loss) on derivatives 12,768 (3,824) 5,561 $ 111,927 $ (5,465) $ (45,064) Totals $ (284,153) $ (350,123) $ 1,819
Schedule of Derivative Instruments	The following tables present information about our derivatives at December 31, 2020 and December 31, 2019. Interest Rate Swaps (1) Notional Amount Weighted Average Remaining Term (Months) Weighted Average Rate December 31, 2020 < 3 years $ 2,230,000 12 0.06 % ≥ 3 years and < 5 years 463,000 45 0.14 % ≥ 5 years and < 7 years 942,000 72 0.28 % ≥ 7 years 1,702,000 113 0.50 % Total or Weighted Average (2) $ 5,337,000 58 0.24 % December 31, 2019 < 3 years $ 2,750,000 19 1.66 % ≥ 3 years and < 5 years 2,850,000 47 1.84 % ≥ 5 years and < 7 years 1,200,000 83 1.86 % ≥ 7 years 1,175,000 118 1.54 % Total or Weighted Average (3) $ 7,975,000 53 1.74 % (1) Pay Fixed/Receive Variable (2) Of this amount, $2,230,000 notional are SOFR based swaps, the last of which matures in 2023; and $3,107,000 notional are Fed Funds based swaps, the last of which matures in 2030. (3) Of this amount, $1,025,000 notional are LIBOR based swaps, the last of which matures in 2023; $375,000 notional are SOFR based swaps, the last of which matures in 2024; and $6,575,000 notional are Fed Funds based swaps, the last of which matures in 2029. TBA Agency Securities Notional Amount Cost Basis Fair Value December 31, 2020 15 Year Long 1.5% $ 200,000 $ 204,758 $ 205,781 2.0% 1,200,000 1,248,015 1,253,354 30 Year Long 2.0% 600,000 619,031 622,934 2.5% 800,000 838,047 841,314 3.5% (200,000) (211,055) (211,406) Total (1) $ 2,600,000 $ 2,698,796 $ 2,711,977 December 31, 2019 15 Year Long 3.0% $ 500,000 $ 511,055 $ 511,885 30 Year Long 2.5% 500,000 494,813 494,395 Total (2) $ 1,000,000 $ 1,005,868 $ 1,006,280 (1) $1,250,000 notional are forward settling. (2) $1,000,000 notional are forward settling.

Stock Based Compensation (Table

Stock Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Schedule of Nonvested Restricted Stock Units Activity	related to awards for the years ended December 31, 2020, December 31, 2019 and December 31, 2018 are summarized below: December 31, 2020 December 31, 2019 December 31, 2018 Number of Awards Weighted Number of Awards Weighted Number of Awards Weighted Unvested RSU Awards Outstanding beginning of period 247 $ 24.82 360 $ 24.82 472 $ 24.82 Granted (1) 502 $ 17.85 6 $ 18.71 — $ — Vested (205) $ 20.41 (119) $ 18.05 (112) $ 22.70 Forfeited (48) $ 23.14 — $ — — $ — Unvested RSU Awards Outstanding end of period 496 $ 19.77 247 $ 24.82 360 $ 24.82 (1) During the year ended December 31, 2020, we granted 358 RSUs to ACM and 144 RSUs to the Board.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2020
Equity [Abstract]
Schedule of Stock Issuances	The following tables present our equity transactions for the years ended December 31, 2020 , December 31, 2019 and December 31, 2018. Transaction Type Completion Date Number of Shares Per Share price (1) Net Proceeds December 31, 2020 Preferred C Underwritten Offering January 28, 2020 3,450 $ 24.14 $ 83,282 Preferred C ATM Sales Agreement January 30, 2020 - December 23, 2020 1,897 $ 24.70 $ 46,856 Common Stock ATM Sales Agreement April 7, 2020 - December 15 2020 6,287 $ 8.68 $ 54,575 Common stock repurchases, net February 26, 2020 - March 3, 2020 (40) $ 19.42 $ (777) December 31, 2019 Preferred B ATM Sales Agreement June 6, 2019-June 19, 2019 100 $ 24.81 $ 2,489 Preferred B ATM Sales Agreement June 25, 2019-December 31, 2019 1,914 $ 24.74 $ 47,306 Common Stock ATM Sales Agreement January 4, 2019-January 11, 2019 884 $ 20.98 $ 18,540 January Public Offering January 17, 2019 6,900 $ 20.00 $ 137,946 February Public Offering February 22, 2019-February 27, 2019 8,280 $ 19.98 $ 165,374 Common stock repurchases May 31, 2019-December 31, 2019 (1,000) $ 17.77 $ (17,768) December 31, 2018 Series B Preferred equity distribution agreement January 2, 2018-January 26, 2018 107 $ 24.62 $ 2,632 DRIP August 21, 2018-December 10, 2018 840 $ 22.61 $ 19,001 Common stock ATM Sales Agreement December 11, 2018-December 19, 2018 883 $ 21.53 $ 19,013 (1) Weighted average price
Dividends Transactions	The following table presents our Series A Preferred Stock dividend transactions prior to full redemption for the year ended December 31, 2019. The table below does not include the final dividend amount of $375 that was paid on July 29, 2019 to holders of record on July 15, 2019. This amount was recorded in other expense in our consolidated statements of operations. 2019 Record Date Payment Date Rate per Series A Preferred Share Aggregate January 15, 2019 January 28, 2019 $ 0.17 374.8 February 15, 2019 February 27, 2019 $ 0.17 374.8 March 15, 2019 March 27, 2019 $ 0.17 374.8 April 15, 2019 April 29, 2019 $ 0.17 374.8 May 15, 2019 May 28, 2019 $ 0.17 374.8 June 15, 2019 June 27, 2019 $ 0.17 374.8 Total dividends paid $ 2,249 The following tables present our Series A Preferred Stock dividend transactions for the year ended December 31, 2018. 2018 Record Date Payment Date Rate per Series A Preferred Share Aggregate January 15, 2018 January 29, 2018 $ 0.17 $ 374.8 February 15, 2018 February 27, 2018 $ 0.17 374.8 March 15, 2018 March 27, 2018 $ 0.17 374.8 April 15, 2018 April 27, 2018 $ 0.17 374.8 May 15, 2018 May 29, 2018 $ 0.17 374.8 June 15, 2018 June 27, 2018 $ 0.17 374.8 July 15, 2018 July 27, 2018 $ 0.17 374.8 August 15, 2018 August 27, 2018 $ 0.17 374.8 September 15, 2018 September 27, 2018 $ 0.17 374.8 October 15, 2018 October 29, 2018 $ 0.17 374.8 November 15, 2018 November 27, 2018 $ 0.17 374.8 December 15, 2018 December 27, 2018 $ 0.17 374.8 Total dividends paid $ 4,498 The following table presents our Series B Preferred Stock dividend transactions prior to full redemption. The table below does not include the final dividend amount of $1,375 that was paid on February 27, 2020 to holders of record on February 15, 2020. This amount was recorded in other expense in our consolidated statements of operations. 2020 Record Date Payment Date Rate per Series B Preferred Share Aggregate January 15, 2020 January 27, 2020 $ 0.16 $ 1,375 The following table present our Series B Preferred Stock dividend transactions for the years ended December 31, 2019 and December 31, 2018. 2019 Record Date Payment Date Rate per Series B Preferred Share Aggregate January 15, 2019 January 28, 2019 $ 0.16 1,045 February 15, 2019 February 27, 2019 $ 0.16 1,045 March 15, 2019 March 27, 2019 $ 0.16 1,045 April 15, 2019 April 29, 2019 $ 0.16 1,045 May 15, 2019 May 28, 2019 $ 0.16 1,045 June 15, 2019 June 27, 2019 $ 0.16 1,059 July 15, 2019 July 29, 2019 $ 0.16 1,100 August 15, 2019 August 27, 2019 $ 0.16 1,142 September 15, 2019 September 27, 2019 $ 0.16 1,168 October 15, 2019 October 28, 2019 $ 0.16 1,190 November 15, 2019 November 27, 2019 $ 0.16 1,210 December 15, 2019 December 27, 2019 $ 0.16 1,291 Total dividends paid $ 13,385 2018 Record Date Payment Date Rate per Series B Preferred Share Aggregate January 15, 2018 January 29, 2018 $ 0.16 $ 1,039 February 15, 2018 February 27, 2018 $ 0.16 1,045 March 15, 2018 March 27, 2018 $ 0.16 1,045 April 15, 2018 April 27, 2018 $ 0.16 1,045 May 15, 2018 May 29, 2018 $ 0.16 1,045 June 15, 2018 June 27, 2018 $ 0.16 1,045 July 15, 2018 July 27, 2018 $ 0.16 1,045 August 15, 2018 August 27, 2018 $ 0.16 1,045 September 15, 2018 September 27, 2018 $ 0.16 1,045 October 15, 2018 October 29, 2018 $ 0.16 1,045 November 15, 2018 November 27, 2018 $ 0.16 1,045 December 15, 2018 December 27, 2018 $ 0.16 1,045 Total dividends paid $ 12,534 The following table presents our Series C Preferred Stock dividend transactions for the year ended December 31, 2020. 2020 Record Date Payment Date Rate per Series C Preferred Share Aggregate February 15, 2020 February 27, 2020 $ 0.14583 $ 678.1 March 15, 2020 March 27, 2020 $ 0.14583 773.4 April 15, 2020 April 27, 2020 $ 0.14583 773.4 May 15, 2020 May 27, 2020 $ 0.14583 773.4 June 15, 2020 June 29, 2020 $ 0.14583 773.4 July 15, 2020 July 27, 2020 $ 0.14583 773.4 August 15, 2020 August 27, 2020 $ 0.14583 773.4 September 15, 2020 September 28, 2020 $ 0.14583 773.4 October 15, 2020 October 27, 2020 $ 0.14583 773.4 November 15, 2020 November 27, 2020 $ 0.14583 773.4 December 15, 2020 December 28, 2020 $ 0.14583 773.4 Total dividends paid $ 8,412 The following tables present our common stock dividend transactions for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. 2020 Record Date Payment Date Rate per common share Aggregate January 15, 2020 January 30, 2020 $ 0.17 $ 10,126 February 14, 2020 February 27, 2020 $ 0.17 10,131 March 16, 2020 March 27, 2020 $ 0.17 10,120 June 15, 2020 June 29, 2020 $ 0.09 5,876 July 15, 2020 July 30, 2020 $ 0.10 6,531 August 17, 2020 August 28, 2020 $ 0.10 6,530 September 15, 2020 September 29, 2020 $ 0.10 6,529 October 15, 2020 October 29, 2020 $ 0.10 6,531 November 16, 2020 November 27, 2020 $ 0.10 6,531 December 15, 2020 December 29, 2020 $ 0.10 6,581 Total dividends paid $ 75,486 2019 Record Date Payment Date Rate per common share Aggregate January 15, 2019 January 28, 2019 $ 0.19 $ 8,540 February 15, 2019 February 28, 2019 $ 0.19 9,851 March 15, 2019 March 27, 2019 $ 0.19 11,423 April 15, 2019 April 29, 2019 $ 0.19 11,424 May 15, 2019 May 28, 2019 $ 0.19 11,424 June 17, 2019 June 27, 2019 $ 0.19 11,350 July 16, 2019 July 29, 2019 $ 0.17 10,114 August 15, 2019 August 27, 2019 $ 0.17 10,099 September 16, 2019 September 27, 2019 $ 0.17 10,075 October 15, 2019 October 28, 2019 $ 0.17 10,059 November 15, 2019 November 27, 2019 $ 0.17 10,059 December 16, 2019 December 27, 2019 $ 0.17 10,059 Total dividends paid $ 124,477 2018 Record Date Payment Date Rate per common share Aggregate January 16, 2018 January 29, 2018 $ 0.19 $ 8,046 February 15, 2018 February 27, 2018 $ 0.19 8,046 March 15, 2018 March 28, 2018 $ 0.19 8,045 April 13, 2018 April 27, 2018 $ 0.19 8,046 May 15, 2018 May 30, 2018 $ 0.19 8,046 June 15, 2018 June 28, 2018 $ 0.19 8,045 July 16, 2018 July 27, 2018 $ 0.19 8,045 August 15, 2018 August 28, 2018 $ 0.19 8,045 September 17, 2018 September 27, 2018 $ 0.19 8,117 October 15, 2018 October 29, 2018 $ 0.19 8,118 November 15, 2018 November 27, 2018 $ 0.19 8,118 December 17, 2018 December 27, 2018 $ 0.19 8,307 Total dividends paid $ 97,024

Net Income (Loss) per Common _2

Net Income (Loss) per Common Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Weighted Average Number of Shares	The following table presents a reconciliation of net loss and the shares used in calculating weighted average basic and diluted earnings per common share for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 Net Loss $ (215,112) $ (249,905) $ (105,966) Less: Preferred dividends (9,787) (15,634) (17,032) Net Loss related to common stockholders $ (224,899) $ (265,539) $ (122,998) Weighted average common shares outstanding – basic 63,070 57,833 42,128 Add: Effect of dilutive non-vested awards, assumed vested — — — Weighted average common shares outstanding – diluted 63,070 57,833 42,128

Comprehensive Income (Loss) p_2

Comprehensive Income (Loss) per Common Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table presents a reconciliation of comprehensive net income (loss) and the shares used in calculating weighted average basic and diluted comprehensive income (loss) per common share for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 Comprehensive Income (Loss) $ (391,554) $ 149,438 $ (129,725) Less: Preferred dividends (9,787) (15,634) (17,032) Comprehensive Income (Loss) available (related) to common stockholders $ (401,341) $ 133,804 $ (146,757) Net Comprehensive Income (Loss) per share available (related) to common stockholders: Basic $ (6.36) $ 2.31 $ (3.48) Diluted $ (6.36) $ 2.30 $ (3.48) Weighted average common shares outstanding: Basic 63,070 57,833 42,128 Add: Effect of dilutive non-vested awards, assumed vested — 247 — Diluted 63,070 58,080 42,128

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	The following table reconciles our GAAP net loss to estimated REIT taxable income (loss) for the years ended December 31, 2020, December 31, 2019 and December 31, 2018. For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 GAAP net loss $ (215,112) $ (249,905) $ (105,966) Book to tax differences: TRS income (51) (147) (265) Premium amortization expense (261) — (1,132) Agency Securities, trading (19,557) — — Credit Risk and Non-Agency Securities 188,075 24,459 26,509 Interest-Only Securities — 85 318 U.S. Treasury Securities (21,357) (2,024) 6,365 Changes in interest rate contracts 268,159 375,493 (1,346) Reversal of (Gain) Loss on Security sales (143,877) (9,611) 152,950 Credit loss expense/OTTI 1,012 — 12,090 Amortization of deferred hedging costs (152,092) (69,302) (56,378) Series A Cumulative Preferred Stock dividend- Called for redemption — 375 — Series B Cumulative Preferred Stock dividend- Called for redemption 1,375 — — Other 1,544 18 16 Estimated taxable income (loss) $ (92,142) $ 69,441 $ 33,161
Schedule of Tax Credit Carryforwards	Net capital losses realized Amount Available to offset capital gains though 2016 (31,204) 2021 2017 (7,375) 2022 2018 (216,634) 2023

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	For the Years Ended December 31, 2020 December 31, 2019 December 31, 2018 ARMOUR management fees $ 29,580 $ 29,513 $ 27,190 Less management fees waived (8,855) — — Total Management fee expense $ 20,725 $ 29,513 $ 27,190 The table below summarizes other transactions with BUCKLER as of and for the years ended December 31, 2020 and December 31, 2019. Transactions with BUCKLER December 31, 2020 December 31, 2019 Repurchase agreements (1) $ 2,998,111 $ 5,107,101 Interest on repurchase agreements $ 38,663 $ 120,090 Collateral posted on repurchase agreements $ 3,117,929 $ 5,341,487

Quarterly Financial Data (una_2

Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	The following tables are a comparative breakdown of our unaudited quarterly financial results for the immediately preceding eight quarters. Quarter Ended March 31, June 30, September 30, December 31, Agency Securities, net of amortization of premium and fees $ 79,776 $ 23,648 $ 25,188 $ 22,594 Credit Risk and Non-Agency Securities, including discount accretion 12,355 4,873 518 — U.S. Treasury Securities 469 — — — BUCKLER Subordinated loan 258 29 24 22 Interest expense- repurchase agreements (51,520) (5,389) (2,954) (3,076) Interest expense- U.S. Treasury Securities sold short — (32) — — Net Interest Income $ 41,338 $ 23,129 $ 22,776 $ 19,540 Realized gain (loss) on sale of Agency Securities (reclassified from Other comprehensive income (loss)) 93,325 36,008 9,468 5,076 Credit loss expense (1,012) — — — Gain on Agency Securities, trading — 7,911 12,149 (503) Gain (Loss) on Credit Risk and Non-Agency Securities (183,111) 190 (6,633) (1) Gain (loss) U.S. Treasury Securities 21,771 — — — Loss on short sale of U.S. Treasury Securities — (414) — — Realized gain (loss) on derivatives (1) (235,148) (180,567) 20,866 16,641 Unrealized gain (loss) on derivatives (133,887) 173,325 6,866 47,751 Expenses (9,935) (10,781) (10,059) (10,046) Management fees waived — 2,947 2,953 2,955 Net Income (Loss) $ (406,659) $ 51,748 $ 58,386 $ 81,413 Dividends declared on preferred stock (2,827) (2,320) (2,320) (2,320) Net Income (Loss) available (related) to common stockholders $ (409,486) $ 49,428 $ 56,066 79,093 Net income (loss) available (related) per share to common stockholders – Basic $ (6.95) $ 0.78 $ 0.87 $ 1.22 Net income (loss) available (related) per share to common stockholders – Diluted $ (6.95) $ 0.77 $ 0.86 $ 1.21 Dividends declared per common share $ 0.51 $ 0.09 $ 0.30 $ 0.30 Weighted average common shares outstanding – Basic 58,884 63,741 64,724 64,895 Weighted average common shares outstanding – Diluted 58,884 64,340 65,272 65,392 Quarter Ended March 31, June 30, September 30, December 31, Agency Securities, net of amortization of premium and fees $ 79,832 $ 113,438 $ 102,134 $ 87,407 Credit Risk and Non-Agency Securities, including discount accretion 13,592 13,383 13,158 12,785 Interest-Only Securities 345 251 — — U.S. Treasury Securities 482 744 128 — BUCKLER Subordinated loan 539 544 479 324 Interest expense- repurchase agreements (60,978) (87,504) (80,293) (59,454) Net Interest Income $ 33,812 $ 40,856 $ 35,606 $ 41,062 Realized loss on sale of Agency Securities (reclassified from Other comprehensive income (loss)) (2,910) (44) 4,569 7,996 Gain (Loss) on Credit Risk and Non-Agency Securities 496 (17,699) (8,842) 1,650 Gain (Loss) on Interest-Only Securities (368) 490 — — Gain (loss) U.S. Treasury Securities (693) 3,453 (736) — Realized gain (loss) on derivatives (1) (22,131) (92,990) (85,076) (13,799) Unrealized gain (loss) on derivatives (113,067) (107,304) 3,845 80,399 Expenses (9,520) (10,012) (10,321) (8,627) Net Income (Loss) $ (114,381) $ (183,250) $ (60,955) $ 108,681 Dividends declared on preferred stock (4,259) (4,274) (3,410) (3,691) Net Income (Loss) available (related) to common stockholders $ (118,640) $ (187,524) $ (64,365) $ 104,990 Net income (loss) available (related) per share to common stockholders – Basic $ (2.21) $ (3.14) $ (1.09) $ 1.78 Net income (loss) available (related) per share to common stockholders – Diluted $ (2.21) $ (3.14) $ (1.09) $ 1.78 Dividends declared per common share $ 0.57 $ 0.57 $ 0.51 $ 0.51 Weighted average common shares outstanding – Basic 53,630 59,654 59,077 58,902 Weighted average common shares outstanding – Diluted 53,630 59,654 59,077 59,149 (1) Interest expense related to our interest rate swap contracts is recorded in realized loss on derivatives on the consolidated statements of operations.

Organization and Nature of Bu_2

Organization and Nature of Business Operations Organization and Nature of Business Operations (Details)	Dec. 31, 2020
Corporate Joint Venture | BUCKLER Securities, LLC
Investments in and Advances to Affiliates [Line Items]
Ownership percentage	10.00%

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020dealer
Fair Value Disclosures [Abstract]
Trading securities, number of dealers	3

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets at Fair Value:
Agency Securities	$ 1,970,902	$ 11,941,766
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)	3,207,420	883,601
Derivatives, at fair value	54,686	24,751
Liabilities at Fair Value:
Derivatives, at fair value	1,217	71,974
Fair Value, Measurements, Recurring
Assets at Fair Value:
Agency Securities	5,178,322	11,941,766
Derivatives, at fair value	54,686	24,751
Liabilities at Fair Value:
Derivatives, at fair value	1,217	71,974
Fair Value, Measurements, Recurring | (Level 1)
Assets at Fair Value:
Agency Securities	0	0
Derivatives, at fair value	0	0
Liabilities at Fair Value:
Derivatives, at fair value	0	0
Fair Value, Measurements, Recurring | (Level 2)
Assets at Fair Value:
Agency Securities	5,178,322	11,941,766
Derivatives, at fair value	54,686	24,751
Liabilities at Fair Value:
Derivatives, at fair value	1,217	71,974
Fair Value, Measurements, Recurring | (Level 3)
Assets at Fair Value:
Agency Securities	0	0
Derivatives, at fair value	0	0
Liabilities at Fair Value:
Derivatives, at fair value	0	0
Credit Risk and Non-Agency Securities
Assets at Fair Value:
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)	$ 0	883,601
Credit Risk and Non-Agency Securities | Fair Value, Measurements, Recurring
Assets at Fair Value:
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)		883,601
Credit Risk and Non-Agency Securities | Fair Value, Measurements, Recurring | (Level 1)
Assets at Fair Value:
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)		0
Credit Risk and Non-Agency Securities | Fair Value, Measurements, Recurring | (Level 2)
Assets at Fair Value:
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)		883,601
Credit Risk and Non-Agency Securities | Fair Value, Measurements, Recurring | (Level 3)
Assets at Fair Value:
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)		$ 0

Investment In Securities - Addi

Investment In Securities - Additional Information (Details) - USD ($)	3 Months Ended					12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Debt securities	$ 5,178,322,000					$ 5,178,322,000	$ 12,825,367,000
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)	3,207,420,000					3,207,420,000	883,601,000
Credit loss expense	0	$ 0	$ 0	$ (1,012,000)		(1,012,000)	0	$ (12,090,000)
TBA Agency Securities
Debt Securities, Available-for-sale [Line Items]
Credit Risk and Non-Agency Securities (including pledged securities of $810,549 at December 31, 2019)	$ 2,711,977,000					$ 2,711,977,000	1,006,280,000
Agency Securities
Debt Securities, Available-for-sale [Line Items]
OTTI					$ 12,090,000		$ 0
Weighted average coupon rate	3.25%					3.25%	3.76%
TBA Agency Securities
Debt Securities, Available-for-sale [Line Items]
Derivative assets (liabilities), net	$ 19,747,000					$ 19,747,000	$ (592,000)

Investment In Securities - Summ

Investment In Securities - Summary of Investment in Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Investment In Securities, Fair Value [Roll Forward]
Beginning balance	$ 12,825,367	$ 7,991,138
Purchases	10,340,353	10,954,337
Proceeds from sales	(16,491,693)	(4,699,251)
Principal repayments	(1,262,930)	(1,755,047)
Gains (losses)	(181,206)	386,705
Credit loss expense	(1,012)
Amortization/accretion	(50,557)	(52,515)
Ending balance	$ 5,178,322	$ 12,825,367
Percentage of Portfolio	100.00%	100.00%
Agency Securities
Investment In Securities, Fair Value [Roll Forward]
Beginning balance	$ 11,941,766	$ 7,051,954
Purchases	1,768,688	9,130,512
Proceeds from sales	(10,800,879)	(2,894,339)
Principal repayments	(873,650)	(1,701,406)
Gains (losses)	(32,565)	408,954
Credit loss expense	(1,012)
Amortization/accretion	(31,446)	(53,909)
Ending balance	$ 1,970,902	$ 11,941,766
Percentage of Portfolio	38.06%	93.11%
Agency Trading Securities
Investment In Securities, Fair Value [Roll Forward]
Beginning balance	$ 0	$ 0
Purchases	3,711,961	0
Proceeds from sales	(158,708)	0
Principal repayments	(343,514)	0
Gains (losses)	19,557	0
Credit loss expense	0
Amortization/accretion	(21,876)	0
Ending balance	$ 3,207,420	$ 0
Percentage of Portfolio	61.94%	0.00%
Credit Risk and Non-Agency Securities
Investment In Securities, Fair Value [Roll Forward]
Beginning balance	$ 883,601	$ 819,915
Purchases	237,928	138,767
Proceeds from sales	(889,057)	0
Principal repayments	(45,766)	(53,641)
Gains (losses)	(189,555)	(24,396)
Credit loss expense	0
Amortization/accretion	2,849	2,956
Ending balance	$ 0	$ 883,601
Percentage of Portfolio	0.00%	6.89%
Interest Only Securities
Investment In Securities, Fair Value [Roll Forward]
Beginning balance	$ 0	$ 20,623
Purchases	0	0
Proceeds from sales	0	(18,822)
Principal repayments	0	0
Gains (losses)	0	123
Credit loss expense	0
Amortization/accretion	0	(1,924)
Ending balance	$ 0	$ 0
Percentage of Portfolio	0.00%	0.00%
US Treasury Securities
Investment In Securities, Fair Value [Roll Forward]
Beginning balance	$ 0	$ 98,646
Purchases	4,621,776	1,685,058
Proceeds from sales	(4,643,049)	(1,786,090)
Principal repayments	0	0
Gains (losses)	21,357	2,024
Credit loss expense	0
Amortization/accretion	(84)	362
Ending balance	$ 0	$ 0
Percentage of Portfolio	0.00%	0.00%

Investment In Securities - Unre

Investment In Securities - Unrealized Gain or Loss Position and Components of Carrying Value of Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Principal Amount	$ 1,738,906	$ 11,324,705
Total Available for Sale Securities	1,791,871	11,586,293
Gross Unrealized Loss	(44)	(792)
Gross Unrealized Gain	179,075	356,265
Fair Value	1,970,902	11,941,766
Fannie Mae
Debt Securities, Available-for-sale [Line Items]
Principal Amount	1,359,136	8,779,331
Total Available for Sale Securities	1,397,206	8,975,140
Gross Unrealized Loss	(1)	(291)
Gross Unrealized Gain	159,603	294,937
Fair Value	1,556,808	9,269,786
Freddie Mac
Debt Securities, Available-for-sale [Line Items]
Principal Amount	354,382	2,522,870
Total Available for Sale Securities	368,686	2,587,512
Gross Unrealized Loss	0	(40)
Gross Unrealized Gain	19,246	61,323
Fair Value	387,932	2,648,795
Ginnie Mae
Debt Securities, Available-for-sale [Line Items]
Principal Amount	25,388	22,504
Total Available for Sale Securities	25,979	23,641
Gross Unrealized Loss	(43)	(461)
Gross Unrealized Gain	226	5
Fair Value	$ 26,162	$ 23,185

Investment In Securities - Gros

Investment In Securities - Gross Unrealized Losses and Estimated Fair Value of Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value
Less than 12 Months	$ 8,811	$ 2,136
Greater than or equal to 12 Months	0	43,939
Fair Value	8,811	46,075
Unrealized Losses
Less than 12 Months	(44)	(10)
Greater than or equal to 12 Months	0	(782)
Unrealized Losses	$ (44)	$ (792)

Investment In Securities - Su_2

Investment In Securities - Summary of Weighted Average Lives of Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value
Less than 1 year	$ 71	$ 0
Greater than or equal to 1 year and less than 3 years	548,352	22,237
Greater than or equal to 3 years and less than 5 years	282,739	6,542,389
Greater than or equal to 5 years	1,139,740	5,377,140
Total Available for Sale Securities	1,970,902	11,941,766
Amortized Cost
Less than 1 year	72	0
Greater than or equal to 1 year and less than 3 years	520,657	22,254
Greater than or equal to 3 years and less than 5 years	269,716	6,365,623
Greater than or equal to 5 years	1,001,426	5,198,416
Total Available for Sale Securities	$ 1,791,871	$ 11,586,293

Investment In Securities - Carr

Investment In Securities - Carrying Value of Trading Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt and Equity Securities, FV-NI [Line Items]
Principal Amount	$ 2,991,482	$ 848,452
Amortized Cost	3,186,729	824,844
Gross Unrealized Loss	(1,871)	(3)
Gross Unrealized Gain	22,562	58,760
Fair Value	3,207,420	883,601
Credit Risk Transfer
Debt and Equity Securities, FV-NI [Line Items]
Principal Amount		754,729
Amortized Cost		751,940
Gross Unrealized Loss		0
Gross Unrealized Gain		52,024
Fair Value		803,964
Non-Agency Securities
Debt and Equity Securities, FV-NI [Line Items]
Principal Amount		93,723
Amortized Cost		72,904
Gross Unrealized Loss		(3)
Gross Unrealized Gain		6,736
Fair Value		$ 79,637
Fannie Mae | Agency Securities
Debt and Equity Securities, FV-NI [Line Items]
Principal Amount	2,420,828
Amortized Cost	2,585,409
Gross Unrealized Loss	(1,441)
Gross Unrealized Gain	18,211
Fair Value	2,602,179
Freddie Mac | Agency Securities
Debt and Equity Securities, FV-NI [Line Items]
Principal Amount	570,654
Amortized Cost	601,320
Gross Unrealized Loss	(430)
Gross Unrealized Gain	4,351
Fair Value	$ 605,241

Investment In Securities - Weig

Investment In Securities - Weighted Average Lives of Trading Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value
Less than 1 year	$ 0	$ 0
Greater than or equal to 1 year and less than 3 years	649,425	389,883
Greater than or equal to 3 years and less than 5 years	1,522,509	407,656
Greater than or equal to 5 years	1,035,486	86,062
Total	3,207,420	883,601
Amortized Cost
Less than 1 year	0	0
Greater than or equal to 1 year and less than 3 years	650,328	369,600
Greater than or equal to 3 years and less than 5 years	1,506,035	375,030
Greater than or equal to 5 years	1,030,366	80,214
Amortized Cost	$ 3,186,729	$ 824,844

Repurchase Agreements - Additio

Repurchase Agreements - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)counterparty	Dec. 31, 2019USD ($)counterparty
Concentration Risk [Line Items]
Number of counterparties with master repurchase agreements	33	49
Repurchase agreements, carrying amount | $	$ 4,536,065	$ 11,354,547
Number of counterparties with repurchase agreements outstanding	18	25
Counterparty Concentration Risk | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Number of counterparties	1	2
Counterparty Concentration Risk | BUCKLER Securities, LLC | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	66.10%	45.00%
Counterparty Concentration Risk | BUCKLER Securities, LLC | Stockholders' Equity, Total
Concentration Risk [Line Items]
Percentage of concentration risk	8.30%	14.80%
Weighted average maturity	21 days	7 days
Counterparty Concentration Risk | One Repurchase Agreement Counterparty | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	9.00%
Counterparty Concentration Risk | Two Repurchase Agreement Counterparties | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk		12.70%
Minimum | Counterparty Concentration Risk | One Repurchase Agreement Counterparty | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	5.00%
Minimum | Counterparty Concentration Risk | Two Repurchase Agreement Counterparties | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk		5.00%
Maximum
Concentration Risk [Line Items]
Ratio of indebtedness to net capital	12
Maximum | Counterparty Concentration Risk | One Repurchase Agreement Counterparty | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk	10.00%
Maximum | Counterparty Concentration Risk | Two Repurchase Agreement Counterparties | Repurchase Agreement Borrowings
Concentration Risk [Line Items]
Percentage of concentration risk		10.00%

Repurchase Agreements - Contrac

Repurchase Agreements - Contractual Repricing, Master Repurchase Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 4,536,065	$ 11,354,547
Weighted Average Contractual Rate	0.23%
Weighted Average Maturity in days	21 days
Haircut (as a percent)	3.13%
Agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Balance		$ 10,667,284
Weighted Average Contractual Rate		2.54%
Weighted Average Maturity in days		9 days
Haircut (as a percent)		4.36%
Credit Risk and Non-Agency Securities
Assets Sold under Agreements to Repurchase [Line Items]
Balance		$ 11,354,547
Weighted Average Contractual Rate		2.54%
Weighted Average Maturity in days		9 days
Haircut (as a percent)		5.16%
≤ 30 days | Agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 3,618,255	$ 10,241,137
Weighted Average Contractual Rate	0.23%	2.56%
Weighted Average Maturity in days	15 days	8 days
Haircut (as a percent)	3.12%	4.35%
≤ 30 days | Credit Risk and Non-Agency Securities
Assets Sold under Agreements to Repurchase [Line Items]
Balance		$ 687,263
Weighted Average Contractual Rate		2.45%
Weighted Average Maturity in days		15 days
Haircut (as a percent)		16.25%
> 30 days to ≤ 60 days | Agency securities
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 917,810	$ 426,147
Weighted Average Contractual Rate	0.23%	1.99%
Weighted Average Maturity in days	45 days	34 days
Haircut (as a percent)	3.20%	4.61%

Derivatives - Offsetting Assets

Derivatives - Offsetting Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Offsetting Assets [Line Items]
Gross Amounts	$ 54,686	$ 24,751
Gross Amounts Not Offset, Financial Instruments	(1,217)	(71,382)
Gross Amounts Not Offset, Cash Collateral	(41,715)	83,066
Total Net	11,754	36,435
Interest rate swap contracts
Offsetting Assets [Line Items]
Gross Amounts	34,588	23,659
Gross Amounts Not Offset, Financial Instruments	(866)	(70,290)
Gross Amounts Not Offset, Cash Collateral	(27,773)	83,066
Total Net	5,949	36,435
TBA Agency Securities
Offsetting Assets [Line Items]
Gross Amounts	20,098	1,092
Gross Amounts Not Offset, Financial Instruments	(351)	(1,092)
Gross Amounts Not Offset, Cash Collateral	(13,942)	0
Total Net	$ 5,805	$ 0

Derivatives - Offsetting Liabil

Derivatives - Offsetting Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Offsetting Liabilities [Line Items]
Gross Amounts	$ (1,217)	$ (71,974)
Gross Amounts Not Offset, Financial Instruments	1,217	71,382
Gross Amounts Not Offset, Cash Collateral	0	377
Total Net	0	(215)
Interest rate swap contracts
Offsetting Liabilities [Line Items]
Gross Amounts	(866)	(70,290)
Gross Amounts Not Offset, Financial Instruments	866	70,290
Gross Amounts Not Offset, Cash Collateral	0	0
Total Net	0	0
TBA Agency Securities
Offsetting Liabilities [Line Items]
Gross Amounts	(351)	(1,684)
Gross Amounts Not Offset, Financial Instruments	351	1,092
Gross Amounts Not Offset, Cash Collateral	0	377
Total Net	$ 0	$ (215)

Derivatives - Location and Info

Derivatives - Location and Information of Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain (loss)	$ 16,641	$ 20,866	$ (180,567)	$ (235,148)	$ (13,799)	$ (85,076)	$ (92,990)	$ (22,131)	$ (378,208)	[1]	$ (213,996)	[1]	$ (47,497)	[1]
Unrealized gain (loss) on derivatives	$ 47,751	$ 6,866	$ 173,325	$ (133,887)	$ 80,399	$ 3,845	$ (107,304)	$ (113,067)	94,055		(136,127)		49,316
Subtotal									(284,153)		(350,123)		1,819
Interest rate swap contracts
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain (loss)									(461,374)		(237,725)		2,655
Interest income									30,076		187,899		124,714
Interest expense									(46,069)		(162,529)		(124,241)
Unrealized gain (loss) on derivatives									81,287		(132,303)		43,755
Subtotal									(396,080)		(344,658)		46,883
TBA Agency Securities
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain (loss)									99,159		(1,641)		(50,625)
Unrealized gain (loss) on derivatives									12,768		(3,824)		5,561
Subtotal									$ 111,927		$ (5,465)		$ (45,064)
[1]	Interest expense related to our interest rate swap contracts is recorded as realized loss on derivatives on the consolidated statements of operations. For additional information, see Note 8 to the consolidated financial statements.

Derivatives - Interest Rate Swa

Derivatives - Interest Rate Swap Contracts, Swaptions and Futures Contracts (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Notional Amount	$ 5,337,000,000	$ 7,975,000,000
Weighted Average Remaining Term (Months)	58 months	53 months
Weighted Average Rate	0.24%	1.74%
London Interbank Offered Rate (LIBOR) Swap Rate
Derivative [Line Items]
Notional Amount		$ 1,025,000
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Derivative [Line Items]
Notional Amount	$ 2,230,000,000	375,000
Fed Funds Effective Rate Overnight Index Swap Rate
Derivative [Line Items]
Notional Amount	3,107,000,000	6,575,000
Less than 3 years
Derivative [Line Items]
Notional Amount	$ 2,230,000,000	$ 2,750,000,000
Weighted Average Remaining Term (Months)	12 months	19 months
Weighted Average Rate	0.06%	1.66%
Greater than or equal to 3 years and less than 5 years
Derivative [Line Items]
Notional Amount	$ 463,000,000	$ 2,850,000,000
Weighted Average Remaining Term (Months)	45 months	47 months
Weighted Average Rate	0.14%	1.84%
Greater than or equal to 5 years and less than 7 years
Derivative [Line Items]
Notional Amount	$ 942,000,000	$ 1,200,000,000
Weighted Average Remaining Term (Months)	72 months	83 months
Weighted Average Rate	0.28%	1.86%
Greater than 7 years
Derivative [Line Items]
Notional Amount	$ 1,702,000,000	$ 1,175,000,000
Weighted Average Remaining Term (Months)	113 months	118 months
Weighted Average Rate	0.50%	1.54%
Minimum | Greater than or equal to 3 years and less than 5 years
Derivative [Line Items]
Derivative, remaining maturity	3 years	3 years
Minimum | Greater than or equal to 5 years and less than 7 years
Derivative [Line Items]
Derivative, remaining maturity	5 years	5 years
Minimum | Greater than 7 years
Derivative [Line Items]
Derivative, remaining maturity	7 years	7 years
Maximum | Less than 3 years
Derivative [Line Items]
Derivative, remaining maturity	3 years	3 years
Maximum | Greater than or equal to 3 years and less than 5 years
Derivative [Line Items]
Derivative, remaining maturity	5 years	5 years
Maximum | Greater than or equal to 5 years and less than 7 years
Derivative [Line Items]
Derivative, remaining maturity	7 years	7 years

Derivatives - TBA Agency Securi

Derivatives - TBA Agency Securities (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Notional Amount	$ 5,337,000,000	$ 7,975,000,000
TBA Agency Securities, 15-year, 1.5%
Derivative [Line Items]
Derivative, Fixed Interest Rate	1.50%
Notional Amount	$ 200,000,000
Cost Basis	204,758,000
Fair Value	$ 205,781,000
TBA Agency Securities, 15-year, 2.0%
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.00%
Notional Amount	$ 1,200,000,000
Cost Basis	1,248,015,000
Fair Value	$ 1,253,354,000
TBA Agency Securities, 15-year, 3.0%
Derivative [Line Items]
Derivative, Fixed Interest Rate		3.00%
Notional Amount		$ 500,000,000
Cost Basis		511,055,000
Fair Value		$ 511,885,000
TBA Agency Securities, 30-year, 2.0%
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.00%
Notional Amount	$ 600,000,000
Cost Basis	619,031,000
Fair Value	$ 622,934,000
TBA Agency Securities, 30-year, 2.5%
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.50%	2.50%
Notional Amount	$ 800,000,000	$ 500,000,000
Cost Basis	838,047,000	494,813,000
Fair Value	$ 841,314,000	494,395,000
TBA Agency Securities, 30-year, 3.5%
Derivative [Line Items]
Derivative, Fixed Interest Rate	3.50%
Notional Amount	$ (200,000,000)
Cost Basis	(211,055,000)
Fair Value	(211,406,000)
TBA Agency Securities
Derivative [Line Items]
Notional Amount	2,600,000,000	1,000,000,000
Cost Basis	2,698,796,000	1,005,868,000
Fair Value	2,711,977,000	1,006,280,000
Notional amount, forward settling	$ 1,250,000,000	$ 1,000,000,000

Derivatives - Additional Inform

Derivatives - Additional Information (Details)	Dec. 31, 2020
Maximum
Derivative [Line Items]
Ratio of indebtedness to net capital	12

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands	Apr. 25, 2016lawsuit	Apr. 24, 2016defendant	Mar. 01, 2016lawsuit	Dec. 31, 2020USD ($)	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jan. 13, 2021USD ($)
Other Commitments [Line Items]
Monthly percentage of effective management fee percentage				8.33%				8.33%
Gross equity raised				$ 2,944,169				$ 2,944,169	$ 2,965,163	$ 2,658,969
Management fees waived				$ 2,955	$ 2,953	$ 2,947	$ 0	$ 8,855	$ 0	$ 0
Subsequent Event
Other Commitments [Line Items]
Fee waiver adjustment, first quarter											$ 2,400
Fee waiver adjustment, every month thereafter											$ 800
Transactions Case
Other Commitments [Line Items]
Number of new claims filed | lawsuit			9
Number of defendants, current directors | defendant		8
Number of consolidated claims | lawsuit	1
ARRM
Other Commitments [Line Items]
Percentage of gross equity raised used in calculation of management fee up to 1 Billion				1.50%				1.50%
Percentage of gross equity raised used in calculation of management fee in excess of 1 Billion				0.75%				0.75%
Effective management fee				1.00%				1.00%	1.00%	1.03%
Management fee waived percentage						40.00%
Management fees waived								$ 8,855	$ 0	$ 0

Stock Based Compensation - Addi

Stock Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonemployee services transaction, quarterly fee		$ 33
The 2009 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capital shares reserved for future issuance (in shares)		677,000
Compensation cost not yet recognized		$ 9,817
Period for recognition for compensation cost not yet recognized		2 years 3 months 18 days
The 2009 Stock Incentive Plan | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		502,000	6,000	0
Unvested RSU awards outstanding (in dollars per share)		$ 19.77	$ 24.82	$ 24.82	$ 24.82
The 2009 Stock Incentive Plan | Restricted Stock Units (RSUs) | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capital shares reserved for future issuance (in shares)	42,000
The 2009 Stock Incentive Plan | Restricted Stock Units (RSUs) | Armour Capital Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		358,000
The 2009 Stock Incentive Plan | Restricted Stock Units (RSUs) | Armour Capital Management | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	535,000
The 2009 Stock Incentive Plan | Restricted Stock Units (RSUs) | Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		144,000
The 2009 Stock Incentive Plan | Restricted Stock Units (RSUs) | Director | Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	100,000

Stock Based Compensation - Sche

Stock Based Compensation - Schedule of Restricted Stock Units (Details) - The 2009 Stock Incentive Plan - Restricted Stock Units (RSUs) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of Awards
Unvested RSU Awards Outstanding beginning of period (in shares)	247	360	472
Granted (in shares)	502	6	0
Vested (in shares)	(205)	(119)	(112)
Forfeited (in shares)	(48)	0	0
Unvested RSU Awards Outstanding end of period (in shares)	496	247	360
Weighted Average Grant Date Fair Value per Award
Unvested RSU Awards Outstanding beginning of period (in dollars per share)	$ 24.82	$ 24.82	$ 24.82
Granted (in dollars per share)	17.85	18.71	0
Vested (in dollars per share)	20.41	18.05	22.70
Forfeited (in dollars per share)	23.14	0	0
Unvested RSU Awards Outstanding end of period (in dollars per share)	$ 19.77	$ 24.82	$ 24.82
Director
Number of Awards
Granted (in shares)	144
Armour Capital Management
Number of Awards
Granted (in shares)	358

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($)	Dec. 28, 2020	Nov. 27, 2020	Oct. 27, 2020	Sep. 28, 2020	Aug. 27, 2020	Jul. 27, 2020	Jun. 29, 2020	May 27, 2020	Apr. 27, 2020	Mar. 27, 2020	Mar. 02, 2020	Feb. 27, 2020	Jan. 29, 2020	Jan. 28, 2020	Jan. 27, 2020	Jan. 24, 2020	Jan. 23, 2020	Dec. 27, 2019	Nov. 27, 2019	Oct. 28, 2019	Sep. 27, 2019	Aug. 27, 2019	Jul. 29, 2019	Jun. 27, 2019	Jun. 25, 2019	Jun. 24, 2019	May 28, 2019	Apr. 29, 2019	Mar. 27, 2019	Feb. 27, 2019	Jan. 28, 2019	Dec. 27, 2018	Nov. 27, 2018	Oct. 29, 2018	Sep. 27, 2018	Aug. 27, 2018	Jul. 27, 2018	Jun. 27, 2018	May 29, 2018	Apr. 27, 2018	Mar. 27, 2018	Feb. 27, 2018	Jan. 29, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Feb. 15, 2019
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																																												50,000,000	50,000,000
Preferred stock, par value (in dollars per share)																										$ 0.001																		$ 0.001	$ 0.001
Shares authorized, increase (decrease) (in shares)																										10,320,000
Preferred stock, undesignated shares authorized (in shares)																																												31,617,000
Common stock, shares authorized (in shares)																																												125,000,000	125,000,000
Common stock, par value (in dollars per share)																																												$ 0.001	$ 0.001
Common stock, shares issued (in shares)																																												65,290,000	58,877,000
Common stock, shares outstanding (in shares)																																												65,290,000	58,877,000
Remaining shares authorized to be repurchased (in shares)																																												8,210,000	8,250,000
Common Stock
Class of Stock [Line Items]
Per Share price (in dollars per share)																																												$ 19.42	$ 17.77	$ 22.61
Proceeds from issuance of common stock																																														$ 19,001,000
At-The-Market Offering Program
Class of Stock [Line Items]
Common stock, shares authorized (in shares)																																															17,000
Common stock, par value (in dollars per share)																																															$ 0.001
Sale of stock, commission rate																																															2.00%
Common Stock ATM Sales Agreement | Common Stock
Class of Stock [Line Items]
Per Share price (in dollars per share)																																												$ 8.68	$ 20.98	$ 21.53
Proceeds from issuance of common stock																																												$ 54,575,000	$ 18,540,000	$ 19,013,000
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share)																																													$ 0.001
Preferred stock, dividend rate																										7.875%																		7.875%	7.875%	7.875%
Preferred stock, designated but unissued shares authorized (in shares)																										17,970,000																			9,587,000
Preferred stock, called for redemption (in shares)																8,383,000
Preferred stock, liquidation preference per share (in dollars per share)																$ 25																													$ 25
Payments of dividends												$ 1,375,000			$ 1,375,000			$ 1,291,000	$ 1,210,000	$ 1,190,000	$ 1,168,000	$ 1,142,000	$ 1,100,000	$ 1,059,000			$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,039,000	$ 1,375,000	$ 13,385,000	$ 12,534,000
Preferred stock, shares issued (in shares)																																													8,383,000
Preferred stock, aggregate liquidation preference																																													$ 209,583,000
Preferred stock issued (in shares)																																														107,000
Proceeds from issuance of preferred stock, net																																												$ 0	44,289,000	$ 2,632,000
Per Share price (in dollars per share)																																														$ 24.62
Percent of outstanding shares intended to be redeemed													100.00%
Proceeds from issuance of common stock																																													$ 49,795,000	$ 2,632,000
Preferred stock, shares outstanding (in shares)																																													8,383,000
Series B Preferred Stock | June 24, 2019, Preferred B ATM Sales Agreement
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																										9,000,000
Preferred stock issued (in shares)											1,914,000
Proceeds from issuance of preferred stock, net											$ 47,306,000
Payments of stock issuance costs											$ 689,000
Series B Preferred Stock | Dividend Reinvestment Program
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																										2,500,000
Preferred stock issued (in shares)																																												16
Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)														10,000,000
Preferred stock, par value (in dollars per share)														$ 0.001																														$ 0.001
Preferred stock, dividend rate														7.00%																														7.00%	7.00%	7.00%
Preferred stock, liquidation preference per share (in dollars per share)																																												$ 25
Payments of dividends	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400		$ 678,100																																$ 8,412,000	$ 0	$ 0
Preferred stock, shares issued (in shares)																																												5,347,000
Preferred stock, aggregate liquidation preference																																												$ 133,675,000
Proceeds from issuance of preferred stock, net																																												130,138,000	$ 0	$ 0
Accrued or unpaid dividends																																												$ 0
Unnissued preferred stock (in shares)																																												4,653,000
Proceeds from issuance of common stock																																												$ 130,138,000
Preferred stock, shares outstanding (in shares)																																												5,347,000
Series C Preferred Stock | January 23, 2020 Underwriting Agreement
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																	3,000,000
Preferred stock, par value (in dollars per share)																	$ 0.001
Preferred stock, dividend rate																	7.00%
Preferred stock, liquidation preference per share (in dollars per share)																	$ 25
Payments of stock issuance costs														$ 2,968,000
Per Share price (in dollars per share)																	$ 25
Series C Preferred Stock | Preferred C Underwritten Offering
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																	450,000
Per Share price (in dollars per share)																																												$ 24.14
Over-allotment option term																	30 days
Proceeds from issuance of common stock														$ 83,282,000
Series C Preferred Stock | January 29, 2020, Equity Sales Agreement
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)													6,550,000
Preferred stock issued (in shares)																																												1,897,000
Payments of stock issuance costs																																												$ 726,000
Proceeds from issuance of common stock																																												46,856,000
Series C Preferred Stock | At-The-Market Offering Program
Class of Stock [Line Items]
Payments of stock issuance costs																																												$ 954,000
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividend rate																																												8.25%	8.25%	8.25%
Preferred stock, called for redemption (in shares)																									2,181,000
Preferred stock, liquidation preference per share (in dollars per share)																									$ 25
Payments of dividends																							$ 375,000	$ 374,800			$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 0	$ 2,249,000	$ 4,498,000

Stockholders' Equity - Equity T

Stockholders' Equity - Equity Transactions (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	Jan. 28, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Payments for common stock repurchased		$ (777)	$ (16,965)	$ 0
Common Stock
Class of Stock [Line Items]
Shares issued (in shares)				840
Common stock repurchased (in shares)		40	1,000
Per Share price (in dollars per share)		$ 19.42	$ 17.77	$ 22.61
Proceeds from issuance of common stock				$ 19,001
Payments for common stock repurchased		$ (777)	$ (17,768)
Common Stock ATM Sales Agreement | Common Stock
Class of Stock [Line Items]
Shares issued (in shares)		6,287	884	883
Per Share price (in dollars per share)		$ 8.68	$ 20.98	$ 21.53
Proceeds from issuance of common stock		$ 54,575	$ 18,540	$ 19,013
January Public Offering | Common Stock
Class of Stock [Line Items]
Shares issued (in shares)			6,900
Per Share price (in dollars per share)			$ 20
Proceeds from issuance of common stock			$ 137,946
February Public Offering | Common Stock
Class of Stock [Line Items]
Shares issued (in shares)			8,280
Per Share price (in dollars per share)			$ 19.98
Proceeds from issuance of common stock			$ 165,374
Series C Preferred Stock
Class of Stock [Line Items]
Proceeds from issuance of common stock		130,138
Proceeds from issuance of preferred stock, net		$ 130,138	0	$ 0
Series C Preferred Stock | Preferred C Underwritten Offering
Class of Stock [Line Items]
Shares issued (in shares)	3,450
Per Share price (in dollars per share)		$ 24.14
Proceeds from issuance of common stock	$ 83,282
Series C Preferred Stock | Preferred C ATM Sales Agreement
Class of Stock [Line Items]
Shares issued (in shares)		1,897
Per Share price (in dollars per share)		$ 24.70
Proceeds from issuance of common stock		$ 46,856
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock issued (in shares)				107
Per Share price (in dollars per share)				$ 24.62
Proceeds from issuance of common stock			49,795	$ 2,632
Proceeds from issuance of preferred stock, net		$ 0	$ 44,289	$ 2,632
Series B Preferred Stock | Preferred B ATM Sales Agreement
Class of Stock [Line Items]
Preferred stock issued (in shares)			100
Per Share price (in dollars per share)			$ 24.81
Proceeds from issuance of preferred stock, net			$ 2,489
Series B Preferred Stock | Preferred B ATM Sales Agreement
Class of Stock [Line Items]
Preferred stock issued (in shares)			1,914
Per Share price (in dollars per share)			$ 24.74
Proceeds from issuance of preferred stock, net			$ 47,306

Stockholders' Equity - Dividend

Stockholders' Equity - Dividend Transactions (Details) - USD ($)	Dec. 29, 2020	Dec. 28, 2020	Nov. 27, 2020	Oct. 29, 2020	Oct. 27, 2020	Sep. 29, 2020	Sep. 28, 2020	Aug. 28, 2020	Aug. 27, 2020	Jul. 30, 2020	Jul. 27, 2020	Jun. 29, 2020	May 27, 2020	Apr. 27, 2020	Mar. 27, 2020	Feb. 27, 2020	Jan. 30, 2020	Jan. 27, 2020	Dec. 27, 2019	Nov. 27, 2019	Oct. 28, 2019	Sep. 27, 2019	Aug. 27, 2019	Jul. 29, 2019	Jun. 27, 2019	May 28, 2019	Apr. 29, 2019	Mar. 27, 2019	Feb. 28, 2019	Feb. 27, 2019	Jan. 28, 2019	Dec. 27, 2018	Nov. 27, 2018	Oct. 29, 2018	Sep. 27, 2018	Aug. 28, 2018	Aug. 27, 2018	Jul. 27, 2018	Jun. 28, 2018	Jun. 27, 2018	May 30, 2018	May 29, 2018	Apr. 27, 2018	Mar. 28, 2018	Mar. 27, 2018	Feb. 27, 2018	Jan. 29, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Aggregate amount paid to holders of record																																																$ 75,486,000	$ 124,477,000	$ 97,024,000
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends cash paid (in dollars per share)																									$ 0.17	$ 0.17	$ 0.17	$ 0.17		$ 0.17	$ 0.17	$ 0.17	$ 0.17	$ 0.17	$ 0.17		$ 0.17	$ 0.17		$ 0.17		$ 0.17	$ 0.17		$ 0.17	$ 0.17	$ 0.17
Payments of dividends																								$ 375,000	$ 374,800	$ 374,800	$ 374,800	$ 374,800		$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800		$ 374,800	$ 374,800		$ 374,800		$ 374,800	$ 374,800		$ 374,800	$ 374,800	$ 374,800	0	2,249,000	4,498,000
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends cash paid (in dollars per share)																		$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16		$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16		$ 0.16	$ 0.16		$ 0.16		$ 0.16	$ 0.16		$ 0.16	$ 0.16	$ 0.16
Payments of dividends																$ 1,375,000		$ 1,375,000	$ 1,291,000	$ 1,210,000	$ 1,190,000	$ 1,168,000	$ 1,142,000	$ 1,100,000	$ 1,059,000	$ 1,045,000	$ 1,045,000	$ 1,045,000		$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000		$ 1,045,000	$ 1,045,000		$ 1,045,000		$ 1,045,000	$ 1,045,000		$ 1,045,000	$ 1,045,000	$ 1,039,000	1,375,000	13,385,000	12,534,000
Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock dividends cash paid (in dollars per share)		$ 0.14583	$ 0.14583		$ 0.14583		$ 0.14583		$ 0.14583		$ 0.14583	$ 0.14583	$ 0.14583	$ 0.14583	$ 0.14583	$ 0.14583
Payments of dividends		$ 773,400	$ 773,400		$ 773,400		$ 773,400		$ 773,400		$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 678,100																																8,412,000	0	0
Common Stock
Class of Stock [Line Items]
Common stock dividends cash paid (in dollars per share)	$ 0.10		$ 0.10	$ 0.10		$ 0.10		$ 0.10		$ 0.10		$ 0.09			$ 0.17	$ 0.17	$ 0.17		$ 0.17	$ 0.17	$ 0.17	$ 0.17	$ 0.17	$ 0.17	$ 0.19	$ 0.19	$ 0.19	$ 0.19	$ 0.19		$ 0.19	$ 0.19	$ 0.19	$ 0.19	$ 0.19	$ 0.19		$ 0.19	$ 0.19		$ 0.19		$ 0.19	$ 0.19		$ 0.19	$ 0.19
Aggregate amount paid to holders of record	$ 6,581,000		$ 6,531,000	$ 6,531,000		$ 6,529,000		$ 6,530,000		$ 6,531,000		$ 5,876,000			$ 10,120,000	$ 10,131,000	$ 10,126,000		$ 10,059,000	$ 10,059,000	$ 10,059,000	$ 10,075,000	$ 10,099,000	$ 10,114,000	$ 11,350,000	$ 11,424,000	$ 11,424,000	$ 11,423,000	$ 9,851,000		$ 8,540,000	$ 8,307,000	$ 8,118,000	$ 8,118,000	$ 8,117,000	$ 8,045,000		$ 8,045,000	$ 8,045,000		$ 8,046,000		$ 8,046,000	$ 8,045,000		$ 8,046,000	$ 8,046,000	$ 75,486,000	$ 124,477,000	$ 97,024,000

Net Income (Loss) per Common _3

Net Income (Loss) per Common Share - Reconciliation of Net Income (Loss) and Shares Used in Calculating Basic and Diluted Earnings Per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net Loss	$ 81,413	$ 58,386	$ 51,748	$ (406,659)	$ 108,681	$ (60,955)	$ (183,250)	$ (114,381)	$ (215,112)	$ (249,905)	$ (105,966)
Less: Preferred dividends	(2,320)	(2,320)	(2,320)	(2,827)	(3,691)	(3,410)	(4,274)	(4,259)	(9,787)	(15,634)	(17,032)
Net Loss related to common stockholders	$ 79,093	$ 56,066	$ 49,428	$ (409,486)	$ 104,990	$ (64,365)	$ (187,524)	$ (118,640)	$ (224,899)	$ (265,539)	$ (122,998)
Basic (in shares)	64,895	64,724	63,741	58,884	58,902	59,077	59,654	53,630	63,070	57,833	42,128
Add: Effect of dilutive non-vested awards, assumed vested (in shares)									0	0	0
Weighted average common shares outstanding – diluted (in shares)	65,392	65,272	64,340	58,884	59,149	59,077	59,654	53,630	63,070	57,833	42,128
Potentially dilutive non-vested awards outstanding									496	247	360

Comprehensive Income (Loss) p_3

Comprehensive Income (Loss) per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Comprehensive Income (Loss)									$ (391,554)	$ 149,438	$ (129,725)
Less: Preferred dividends	$ (2,320)	$ (2,320)	$ (2,320)	$ (2,827)	$ (3,691)	$ (3,410)	$ (4,274)	$ (4,259)	(9,787)	(15,634)	(17,032)
Comprehensive Income (Loss) available (related) to common stockholders									$ (401,341)	$ 133,804	$ (146,757)
Net Comprehensive Income (Loss) per share available (related) to common stockholders:
Basic (in dollars per share)									$ (6.36)	$ 2.31	$ (3.48)
Diluted (in dollars per share)									$ (6.36)	$ 2.30	$ (3.48)
Weighted average common shares outstanding:
Basic (in shares)	64,895	64,724	63,741	58,884	58,902	59,077	59,654	53,630	63,070	57,833	42,128
Add: Effect of dilutive non-vested awards, assumed vested (in shares)									0	247	0
Weighted average common shares outstanding - diluted (in shares)									63,070	58,080	42,128
Potentially dilutive non-vested awards outstanding									496	247	360

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of GAAP Net Income to Estimated REIT Taxable Income (Details) - USD ($) $ in Thousands	Feb. 27, 2020	Jul. 29, 2019	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investments, Owned, Federal Income Tax Note [Line Items]
GAAP net loss			$ 81,413	$ 58,386	$ 51,748	$ (406,659)	$ 108,681	$ (60,955)	$ (183,250)	$ (114,381)	$ (215,112)	$ (249,905)	$ (105,966)
Book to tax differences:
TRS income											(51)	(147)	(265)
Premium amortization expense											(261)	0	(1,132)
Agency Securities, trading											(19,557)	0	0
Credit Risk and Non-Agency Securities											188,075	24,459	26,509
Interest-Only Securities											0	85	318
U.S. Treasury Securities											(21,357)	(2,024)	6,365
Changes in interest rate contracts											268,159	375,493	(1,346)
Reversal of (Gain) Loss on Security sales											(143,877)	(9,611)	152,950
Credit loss expense/OTTI											1,012	0	12,090
Amortization of deferred hedging costs											(152,092)	(69,302)	(56,378)
Other											1,544	18	16
Estimated taxable income (loss)											(92,142)	69,441	33,161
Series A Preferred Stock
Book to tax differences:
Cumulative Preferred Stock dividend- Called for redemption		$ (375)									0	375	0
Series B Preferred Stock
Book to tax differences:
Cumulative Preferred Stock dividend- Called for redemption	$ (1,375)										$ 1,375	$ 0	$ 0

Income Taxes - Capital Gains (L

Income Taxes - Capital Gains (Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Capital Loss Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ (216,634)	$ (7,375)	$ (31,204)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	Feb. 27, 2020	Jul. 29, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Aggregate tax basis of stockholders' equity in excess of assets and liabilities			$ 323,071
Aggregate tax basis of stockholders' equity in excess of assets and liabilities (in dollars per share)			$ 4.95
Common stock, shares issued (in shares)			65,290	58,877
Payment of dividends			$ 86,648	$ 140,486	$ 114,056
Estimated REIT taxable Income			$ (92,142)	$ 69,441	$ 33,161
Percent of dividends that represent nontaxable return of capital			100.00%	56.80%	83.20%
Series A Preferred Stock
Related Party Transaction [Line Items]
Cumulative Preferred Stock dividend- Called for redemption		$ 375	$ 0	$ (375)	$ 0
Series B Preferred Stock
Related Party Transaction [Line Items]
Cumulative Preferred Stock dividend- Called for redemption	$ 1,375		(1,375)	0	$ 0
Interest rate swap contracts
Related Party Transaction [Line Items]
Unrealized gain (loss) yet to be amortized			717,000
ARMOUR TRS, Inc.
Related Party Transaction [Line Items]
Income tax expense			$ 36	$ 25

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details)	1 Months Ended	3 Months Ended	12 Months Ended
	Mar. 31, 2017USD ($)	Jun. 30, 2020	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Mar. 31, 2021USD ($)	Jan. 13, 2021USD ($)	Mar. 18, 2019loan	Mar. 17, 2019loan
Related Party Transaction [Line Items]
Management fees			$ 29,628,000	$ 29,571,000	$ 27,246,000
Number of loans | loan								1	3
Subsequent Event
Related Party Transaction [Line Items]
Fee waiver adjustment, first quarter							$ 2,400,000
Fee waiver adjustment, every month thereafter							$ 800,000
ARRM
Related Party Transaction [Line Items]
Annual management fee			$ 1
Period of written notice of termination			180 days
Management fees			$ 29,580,000	29,513,000	27,190,000
Management fee waived percentage		40.00%
ARRM | Armour Management Agreement
Related Party Transaction [Line Items]
Automatic renewal period of management agreement			5 years
ARRM | Javelin Management Agreement
Related Party Transaction [Line Items]
Automatic renewal period of management agreement			1 year
Management agreement, term			1 year
ARRM | Other Expense
Related Party Transaction [Line Items]
Management fees			$ 157,000	114,000	206,000
ARRM | Stock Based Compensation Expense
Related Party Transaction [Line Items]
Management fees			515,000	348,000	436,000
Javelin Mortgage Investment Corp. | Management Fee
Related Party Transaction [Line Items]
Management fees			$ 1	1
Corporate Joint Venture | BUCKLER Securities, LLC
Related Party Transaction [Line Items]
Ownership percentage	10.00%
Corporate Joint Venture | BUCKLER Securities, LLC
Related Party Transaction [Line Items]
Payments to acquire equity method investments	$ 352,000
Ownership percentage			10.00%
Equity method investments, value			$ 634,000	381,000
Proceeds from divestiture of interest in joint venture			1,408,000
Corporate Joint Venture | BUCKLER Securities, LLC | Forecast
Related Party Transaction [Line Items]
Required annual reduction in share of gross financing profit						$ 306,000
Corporate Joint Venture | Required Regulatory Capital Requirement of Related Party | BUCKLER Securities, LLC
Related Party Transaction [Line Items]
Loans receivable related parties			$ 105,000,000
Related party transaction, rate			0.00%
Related parties loans, proceeds			$ 333,000	$ 1,886,000	$ 2,019,000

Related Party Transactions - Sc

Related Party Transactions - Schedule of Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Management fees					$ 29,628	$ 29,571	$ 27,246
Less management fees waived	$ (2,955)	$ (2,953)	$ (2,947)	$ 0	(8,855)	0	0
ARRM
Related Party Transaction [Line Items]
Management fees					29,580	29,513	27,190
Less management fees waived					(8,855)	0	0
Total Management fee expense					20,725	29,513	$ 27,190
BUCKLER Securities, LLC | Corporate Joint Venture
Related Party Transaction [Line Items]
Repurchase agreements	2,998,111				2,998,111	5,107,101
Interest on repurchase agreements					38,663	120,090
Collateral posted on repurchase agreements	$ 3,117,929				$ 3,117,929	$ 5,341,487

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands

Mar. 29, 2021

Feb. 26, 2021

Jan. 28, 2021

Jan. 27, 2021

Dec. 28, 2020

Nov. 27, 2020

Oct. 27, 2020

Sep. 28, 2020

Aug. 27, 2020

Jul. 27, 2020

Jun. 29, 2020

May 27, 2020

Apr. 27, 2020

Mar. 27, 2020

Feb. 27, 2020

Feb. 16, 2021

Dec. 31, 2020

Dec. 31, 2019

Dec. 31, 2018

Jan. 13, 2021

Subsequent Event [Line Items]

Aggregate amount paid to holders of record

$ 75,486

$ 124,477

$ 97,024

Subsequent Event

Subsequent Event [Line Items]

Fee waiver adjustment, first quarter

$ 2,400

Fee waiver adjustment, every month thereafter

$ 800

Common stock dividends cash paid (in dollars per share)

$ 0.10

Aggregate amount paid to holders of record

$ 6,646

$ 780

Subsequent Event | Forecast

Subsequent Event [Line Items]

Common stock dividends cash paid (in dollars per share)

$ 0.10

$ 0.10

Series C Preferred Stock

Subsequent Event [Line Items]

Preferred stock dividends cash paid (in dollars per share)

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

$ 0.14583

Proceeds from issuance of common stock

$ 130,138

Series C Preferred Stock | Subsequent Event

Subsequent Event [Line Items]

Preferred stock dividends cash paid (in dollars per share)

$ 0.14583

Preferred stock issued (in shares)

434

Proceeds from issuance of common stock

$ 10,594

Payments of stock issuance costs

$ 108

Series C Preferred Stock | Subsequent Event | Forecast

Subsequent Event [Line Items]

Preferred stock dividends cash paid (in dollars per share)

$ 0.14583

$ 0.14583

Quarterly Financial Data (una_3

Quarterly Financial Data (unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Condensed Income Statements, Captions [Line Items]
Agency Securities, net of amortization of premium and fees	$ 22,594,000	$ 25,188,000	$ 23,648,000	$ 79,776,000	$ 87,407,000	$ 102,134,000	$ 113,438,000	$ 79,832,000	$ 151,206,000		$ 382,811,000		$ 218,391,000
Debt securities, trading					324,000	479,000	544,000	539,000
Interest expense- repurchase agreements	(3,076,000)	(2,954,000)	(5,389,000)	(51,520,000)	(59,454,000)	(80,293,000)	(87,504,000)	(60,978,000)	(62,939,000)		(288,229,000)		(154,230,000)
Net Interest Income	19,540,000	22,776,000	23,129,000	41,338,000	41,062,000	35,606,000	40,856,000	33,812,000	106,783,000		151,336,000		128,918,000
Realized gain (loss) on sale of available for sale Agency Securities (reclassified from Other comprehensive income (loss))	5,076,000	9,468,000	36,008,000	93,325,000	7,996,000	4,569,000	(44,000)	(2,910,000)	143,877,000		9,611,000		(152,950,000)
Debt securities, trading					0	(736,000)	3,453,000	(693,000)
Realized gain (loss) on derivatives	16,641,000	20,866,000	(180,567,000)	(235,148,000)	(13,799,000)	(85,076,000)	(92,990,000)	(22,131,000)	(378,208,000)	[1]	(213,996,000)	[1]	(47,497,000)	[1]
Unrealized gain (loss) on derivatives	47,751,000	6,866,000	173,325,000	(133,887,000)	80,399,000	3,845,000	(107,304,000)	(113,067,000)	94,055,000		(136,127,000)		49,316,000
Expenses	(10,046,000)	(10,059,000)	(10,781,000)	(9,935,000)	(8,627,000)	(10,321,000)	(10,012,000)	(9,520,000)	(40,821,000)		(38,480,000)		(37,025,000)
Net Loss	81,413,000	58,386,000	51,748,000	(406,659,000)	108,681,000	(60,955,000)	(183,250,000)	(114,381,000)	(215,112,000)		(249,905,000)		(105,966,000)
Dividends on preferred stock	(2,320,000)	(2,320,000)	(2,320,000)	(2,827,000)	(3,691,000)	(3,410,000)	(4,274,000)	(4,259,000)	(9,787,000)		(15,634,000)		(17,032,000)
Net Loss related to common stockholders	$ 79,093,000	$ 56,066,000	$ 49,428,000	$ (409,486,000)	$ 104,990,000	$ (64,365,000)	$ (187,524,000)	$ (118,640,000)	$ (224,899,000)		$ (265,539,000)		$ (122,998,000)
Net income (loss) available (related) per share to common stockholders - Basic (in dollars per share)	$ 1.22	$ 0.87	$ 0.78	$ (6.95)	$ 1.78	$ (1.09)	$ (3.14)	$ (2.21)	$ (3.57)		$ (4.59)		$ (2.92)
Net income (loss) available (related) per share to common stockholders - Diluted (in dollars per share)	1.21	0.86	0.77	(6.95)	1.78	(1.09)	(3.14)	(2.21)	(3.57)		(4.59)		(2.92)
Dividends declared per common share (in dollars per share)	$ 0.30	$ 0.30	$ 0.09	$ 0.51	$ 0.51	$ 0.51	$ 0.57	$ 0.57	$ 1.20		$ 2.16		$ 2.28
Weighted average common shares outstanding – basic (in shares)	64,895	64,724	63,741	58,884	58,902	59,077	59,654	53,630	63,070		57,833		42,128
Weighted average common shares outstanding - diluted (in shares)	65,392	65,272	64,340	58,884	59,149	59,077	59,654	53,630	63,070		57,833		42,128
Interest expense- U.S. Treasury Securities sold short	$ 0	$ 0	$ (32,000)	$ 0					$ (32,000)		$ 0		$ 0
Credit loss expense	0	0	0	(1,012,000)					(1,012,000)		0		(12,090,000)
Gain on Agency Securities, trading	(503,000)	12,149,000	7,911,000	0					19,557,000		0		0
Loss on short sale of U.S. Treasury Securities	0	0	(414,000)	0					(414,000)		0		0
Less management fees waived	2,955,000	2,953,000	2,947,000	0					8,855,000		0		0
Credit Risk and Non-Agency Securities
Condensed Income Statements, Captions [Line Items]
Debt securities, trading	0	518,000	4,873,000	12,355,000	$ 12,785,000	$ 13,158,000	$ 13,383,000	$ 13,592,000	17,746,000		52,919,000		56,427,000
Debt securities, trading	(1,000)	(6,633,000)	190,000	(183,111,000)	1,650,000	(8,842,000)	(17,699,000)	496,000	(189,555,000)		(24,396,000)		(27,266,000)
Interest Only Securities
Condensed Income Statements, Captions [Line Items]
Debt securities, trading					0	0	251,000	345,000	0		596,000		1,667,000
Debt securities, trading					0	0	490,000	(368,000)	0		123,000		(1,007,000)
US Treasury Securities
Condensed Income Statements, Captions [Line Items]
Debt securities, trading	0	0	0	469,000	$ 0	$ 128,000	$ 744,000	$ 482,000	469,000		1,353,000		4,644,000
Debt securities, trading	0	0	0	21,771,000					21,771,000		2,024,000		(6,365,000)
Corporate Debt Securities
Condensed Income Statements, Captions [Line Items]
Debt securities, trading	$ 22,000	$ 24,000	$ 29,000	$ 258,000					$ 333,000		$ 1,886,000		$ 2,019,000
[1]	Interest expense related to our interest rate swap contracts is recorded as realized loss on derivatives on the consolidated statements of operations. For additional information, see Note 8 to the consolidated financial statements.