Dynex Capital (DX) 10-Q 3 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	9 Months Ended
	Sep. 30, 2017	Oct. 31, 2017	Jun. 30, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	DYNEX CAPITAL INC
Entity Central Index Key	826,675
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		53,219,286
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 310,217,722

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets:
Mortgage-backed securities (including pledged of $2,714,312 and $3,150,610, respectively)	$ 2,921,444	$ 3,212,084
Mortgage loans held for investment, net	16,523	19,036
Cash and cash equivalents	117,702	74,120
Restricted cash	43,987	24,769
Derivative assets	368	28,534
Receivable for securities sold	13,435	0
Principal receivable on investments	3,359	11,978
Accrued interest receivable	19,267	20,396
Other assets, net	7,193	6,814
Total assets	3,143,278	3,397,731
Liabilities:
Repurchase agreements	2,519,230	2,898,952
Payable for unsettled securities	77,357	0
Non-recourse collateralized financing	5,706	6,440
Derivative liabilities	133	6,922
Accrued interest payable	2,720	3,156
Accrued dividends payable	11,620	12,268
Other liabilities	2,413	2,809
Total liabilities	2,619,179	2,930,547
Shareholders' Equity:
Preferred stock, par value $.01 per share; 50,000,000 shares authorized; 5,665,101 and 4,571,937 shares issued and outstanding, respectively ($141,628 and $114,298 aggregate liquidation preference, respectively)	135,828	110,005
Common stock, par value $.01 per share, 200,000,000 shares authorized; 51,262,350 and 49,153,463 shares issued and outstanding, respectively	513	492
Additional paid-in capital	742,845	727,369
Accumulated other comprehensive income (loss)	5,886	(32,609)
Accumulated deficit	(360,973)	(338,073)
Total shareholders' equity	524,099	467,184
Total liabilities and shareholders’ equity	$ 3,143,278	$ 3,397,731

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets:
Pledged MBS	$ 2,714,312	$ 3,150,610
Shareholders' Equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	5,665,101	4,571,937
Preferred stock, shares outstanding	5,665,101	4,571,937
Preferred stock, aggregate liquidation preference	$ 141,628	$ 114,298
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	51,262,350	49,153,463
Common stock, shares outstanding	51,262,350	49,153,463

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Interest income	$ 23,103	$ 21,135	$ 70,378	$ 69,040
Interest expense	9,889	6,068	26,122	18,478
Net interest income	13,214	15,067	44,256	50,562
Gain (loss) on derivative instruments, net	5,993	2,409	(9,634)	(62,153)
Loss on sale of investments, net	(5,211)	0	(10,628)	(4,238)
Fair value adjustments, net	23	34	63	86
Other (loss) income, net	(109)	545	(150)	898
General and administrative expenses:
Compensation and benefits	(2,070)	(1,736)	(6,356)	(5,829)
Other general and administrative	(1,529)	(1,619)	(5,620)	(5,288)
Net income (loss)	10,311	14,700	11,931	(25,962)
Preferred stock dividends	(2,808)	(2,294)	(7,885)	(6,882)
Net income (loss) to common shareholders	7,503	12,406	4,046	(32,844)
Other comprehensive income:
Unrealized gain on available-for-sale investments, net	981	769	28,087	61,260
Reclassification adjustment for loss on sale of investments, net	5,211	0	10,628	4,238
Reclassification adjustment for de-designated cash flow hedges	(48)	(99)	(220)	(152)
Total other comprehensive income	6,144	670	38,495	65,346
Comprehensive income to common shareholders	$ 13,647	$ 13,076	$ 42,541	$ 32,502
Net income (loss) per common share-basic and diluted	$ 0.15	$ 0.25	$ 0.08	$ (0.67)
Weighted average common shares-basic and diluted	49,832	49,147	49,411	49,102

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity Statement - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Total	Preferred Stock	Preferred Stock Including Additional Paid in Capital	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Balance, Preferred stock, Shares outstanding at Dec. 31, 2016	4,571,937	4,571,937
Balance, Common stock, shares outstanding at Dec. 31, 2016	49,153,463			49,153,463
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		1,093,164		2,048,288
Stock Issued During Period, Shares, Restricted Stock Award, Gross				138,166
Shares Paid for Tax Withholding for Share Based Compensation				(77,567)
Balance, Preferred stock, Shares outstanding at Sep. 30, 2017	5,665,101	5,665,101
Balance, Common stock, shares outstanding at Sep. 30, 2017	51,262,350			51,262,350
Balance at Dec. 31, 2016	$ 467,184		$ 110,005	$ 492	$ 727,369	$ (32,609)	$ (338,073)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issuance	40,379		25,884	21	14,474
Restricted stock granted, net of amortization	1,566			1	1,565
Adjustments for tax withholding on share-based compensation	(521)			(1)	(520)
Stock issuance costs	(104)		(61)		(43)
Net income	11,931						11,931
Dividends on preferred stock	(7,885)						(7,885)
Dividends on common stock	(26,946)						(26,946)
Other comprehensive income	38,495					38,495
Balance at Sep. 30, 2017	$ 524,099		$ 135,828	$ 513	$ 742,845	$ 5,886	$ (360,973)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating activities:
Net income (loss)	$ 11,931	$ (25,962)
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Decrease in accrued interest receivable	1,129	3,263
(Decrease) increase in accrued interest payable	(436)	420
Loss on derivative instruments, net	9,634	62,153
Loss on sale of investments, net	(10,628)	(4,238)
Fair value adjustments, net	(63)	(86)
Amortization of investment premiums, net	122,621	112,418
Other amortization and depreciation, net	983	1,186
Stock-based compensation expense	1,567	2,066
Increase in other assets and liabilities, net	(1,905)	(2,060)
Net cash and cash equivalents provided by operating activities	156,089	157,636
Investing activities:
Purchase of investments	(772,590)	(96,816)
Principal payments received on investments	248,298	337,719
Proceeds from sales of investments	792,984	94,033
Principal payments received on mortgage loans held for investment, net	2,641	3,709
Distributions received from limited partnership	0	10,835
Net receipts (payments) on derivatives, including terminations	11,743	(24,483)
Other investing activities	(214)	(105)
Net cash and cash equivalents provided by investing activities	282,862	324,892
Financing activities:
Borrowings under repurchase agreements	60,229,426	19,293,243
Repayments of repurchase agreement borrowings and FHLB advances	(60,609,148)	(19,661,384)
Principal payments on non-recourse collateralized financing	(747)	(1,443)
Proceeds from issuance of preferred stock	25,884	0
Proceeds from issuance of common stock	14,495	102
Cash paid for stock issuance costs	(61)	0
Cash paid for repurchases of common stock	0	(310)
Payments related to tax withholding for stock-based compensation	(521)	(485)
Dividends paid	(35,479)	(39,285)
Net cash and cash equivalents used in financing activities	(376,151)	(409,562)
Net increase in cash, cash equivalents, and restricted cash	62,800	72,966
Cash, cash equivalents, and restricted cash at beginning of period	98,889	85,125
Cash, cash equivalents, and restricted cash at end of period	161,689	158,091
Supplemental Disclosure of Cash Activity:
Cash paid for interest	$ 26,766	$ 18,185

Organization and Summary of Sig

Organization and Summary of Significant Accounting Policies (Notes)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Organization and Summary of Significant Accounting Policies	ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization Dynex Capital, Inc., ("Company") was incorporated in the Commonwealth of Virginia on December 18, 1987 and commenced operations in February 1988. The Company primarily earns income from investing on a leveraged basis in specified pools of Agency and non-Agency mortgage-backed securities (“MBS”) consisting of residential MBS (“RMBS”), commercial MBS (“CMBS”) and CMBS interest-only ("IO") securities that are issued or guaranteed by the U.S. Government or U.S. Government sponsored agencies ("Agency MBS") and MBS issued by others ("non-Agency MBS"). We also invest in other types of mortgage-related securities, such as to-be-announced (“TBA”) forward contracts for the purchase or sale of generic (also referred to as "non-specified") pools of Agency MBS. Basis of Presentation The accompanying unaudited consolidated financial statements of Dynex Capital, Inc. and its subsidiaries (together, “Dynex” or, as appropriate, the “Company”) have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and with the instructions to the Quarterly Report on Form 10-Q and Article 10, Rule 10-01 of Regulation S-X promulgated by the Securities and Exchange Commission (the “SEC”). Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all significant adjustments, consisting of normal recurring accruals, considered necessary for a fair presentation of the consolidated financial statements have been included. Operating results for the three months ended September 30, 2017 are not necessarily indicative of the results that may be expected for any other interim periods or for the entire year ending December 31, 2017. The unaudited consolidated financial statements included herein should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 filed with the SEC. Consolidation The consolidated financial statements include the accounts of the Company and the accounts of its majority owned subsidiaries and variable interest entities ("VIE") for which it is the primary beneficiary. As a primary beneficiary, the Company has both the power to direct the activities that most significantly impact the economic performance of the VIE and a right to receive benefits or absorb losses of the entity that could be potentially significant to the VIE. The Company is required to reconsider its evaluation of whether to consolidate a VIE each reporting period, based upon changes in the facts and circumstances pertaining to the VIE. The Company consolidates certain trusts through which it has securitized mortgage loans as a result of not meeting the sale criteria under GAAP at the time the financial assets were transferred to the trust. All intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates 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 the disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of revenue and expenses during the reported period. Actual results could differ from those estimates. The most significant estimates used by management include, but are not limited to, amortization of premiums and discounts, fair value measurements of its investments, and other-than-temporary impairments. These items are discussed further below within this note to the consolidated financial statements. Income Taxes The Company has elected to be taxed as a real estate investment trust ("REIT") under the Internal Revenue Code of 1986 and the corresponding provisions of state law. To qualify as a REIT, the Company must meet certain tests including investing in primarily real estate-related assets and the required distribution of at least 90% of its annual REIT taxable income to stockholders after consideration of its net operating loss ("NOL") carryforward and not including taxable income retained in its taxable subsidiaries. As a REIT, the Company generally will not be subject to federal income tax on the amount of its income or capital gains that is distributed as dividends to shareholders. The Company assesses its tax positions for all open tax years and determines whether the Company has any material unrecognized liabilities in accordance with Accounting Standards Codification ("ASC") Topic 740. The Company records these liabilities, if any, to the extent they are deemed more likely than not to have been incurred. Net Income (Loss) Per Common Share The Company calculates basic net income (loss) per common share by dividing net income (loss) to common shareholders for the period by weighted-average shares of common stock outstanding for that period. The Company did not have any potentially dilutive securities outstanding during the three or nine months ended September 30, 2017 or September 30, 2016 . Holders of unvested shares of the Company's issued and outstanding restricted common stock are eligible to receive non-forfeitable dividends. As such, these unvested shares are considered participating securities as per ASC Topic 260-10 and therefore are included in the computation of basic net income (loss) per common share using the two-class method. Upon vesting, restrictions on transfer expire on each share of restricted stock, and each such share of restricted stock represents one unrestricted share of common stock. Because the Company's 8.50% Series A Cumulative Redeemable Preferred Stock (the “Series A Preferred Stock”) and 7.625% Series B Cumulative Redeemable Preferred Stock (the “Series B Preferred Stock”) are redeemable at the Company's option for cash only and may convert into shares of common stock only upon a change of control of the Company, the effect of those shares and their related dividends is excluded from the calculation of diluted net income (loss) per common share. Cash and Cash Equivalents Cash and cash equivalents include cash on hand and highly liquid investments with original maturities of three months or less. Restricted Cash Restricted cash consists of cash the Company has pledged to cover initial and variation margin with its financing and derivative counterparties. The Company early adopted Accounting Standards Update ("ASU") No. 2016-18, Statement of Cash Flows (Topic 230) - Restricted Cash , which requires amounts generally described as restricted cash or restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the statement of cash flows. Because this ASU is to be applied retrospectively to each period presented, "net cash and cash equivalents used in financing activities" on the Company's consolidated statement of cash flows for the nine months ended September 30, 2016 now omits "increase in restricted cash" previously reported in the Quarterly Report on Form 10-Q for that period, and that increase is now included within "net increase in cash, cash equivalents, and restricted cash" for that period in order to conform to the current period's presentation. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported on the Company's consolidated balance sheet as of September 30, 2017 that sum to the total of the same such amounts shown on the Company's consolidated statement of cash flows for the nine months ended September 30, 2017 : September 30, 2017 Cash and cash equivalents $ 117,702 Restricted cash 43,987 Total cash, cash equivalents, and restricted cash shown on consolidated statement of cash flows $ 161,689 Mortgage-Backed Securities The Company's investments in Agency and non-Agency RMBS, CMBS, and CMBS IO securities are designated as available-for-sale ("AFS") and are recorded at fair value on the Company's consolidated balance sheet. Changes in unrealized gain (loss) on the Company's MBS are reported in other comprehensive income ("OCI") until it is sold, matures, or is determined to be other than temporarily impaired. Although the Company generally intends to hold its AFS securities until maturity, it may sell any of these securities as part of the overall management of its business. Upon the sale of an AFS security, any unrealized gain or loss is reclassified out of accumulated other comprehensive income ("AOCI") into net income as a realized "gain (loss) on sale of investments, net" using the specific identification method. The Company’s MBS pledged as collateral against repurchase agreements and derivative instruments are included in MBS on the consolidated balance sheets with the fair value of the MBS pledged as collateral disclosed parenthetically. Interest Income, Premium Amortization, and Discount Accretion. Interest income on MBS is accrued based on the outstanding principal balance (or notional balance in the case of interest-only, or "IO", securities) and their contractual terms. Premiums and discounts on the Company's Agency MBS as well as any non-Agency MBS rated 'AA' and higher at the time of purchase are amortized or accreted into interest income over the expected life of such securities using the effective yield method, and adjustments to premium amortization and discount accretion are made for actual cash payments. The Company may also adjust premium amortization and discount accretion for changes in projected future cash payments. The Company's projections of future cash payments are based on input and analysis received from external sources and internal models, and include assumptions about the amount and timing of loan prepayment rates, fluctuations in interest rates, credit losses, and other factors. On at least a quarterly basis, the Company reviews and makes any necessary adjustments to its cash flow projections and updates the yield recognized on these assets. The Company does not estimate future prepayments on its fixed-rate Agency RMBS. The Company holds certain non-Agency MBS that had credit ratings of less than 'AA' at the time of purchase or were not rated by any of the nationally recognized credit rating agencies. A portion of these non-Agency MBS were purchased at discounts to their par value, which management does not believe to be substantial. The discount is accreted into income over the security's expected life based on management's estimate of the security's projected cash flows. Future changes in the timing of projected cash flows or differences arising between projected cash flows and actual cash flows received may result in a prospective change in the effective yield on those securities. Determination of MBS Fair Value. The Company estimates the fair value of the majority of its MBS based upon prices obtained from third-party pricing services and broker quotes. The remainder of the Company's MBS are valued by discounting the estimated future cash flows derived from cash flow models that utilize information such as the security's coupon rate, estimated prepayment speeds, expected weighted average life, collateral composition, estimated future interest rates, expected losses, and credit enhancements as well as certain other relevant information. Refer to Note 5 for further discussion of MBS fair value measurements. Other-than-Temporary Impairment. An MBS is considered impaired when its fair value is less than its amortized cost. The Company evaluates all of its impaired MBS for other-than-temporary impairments ("OTTI") on at least a quarterly basis. An impairment is considered other-than-temporary if: (1) the Company intends to sell the MBS; (2) it is more likely than not that the Company will be required to sell the MBS before its fair value recovers; or (3) the Company does not expect to recover the full amortized cost basis of the MBS. If either of the first two conditions is met, the entire amount of the impairment is recognized in earnings. If the impairment is solely due to the inability to fully recover the amortized cost basis, the security is further analyzed to quantify any credit loss, which is the difference between the present value of cash flows expected to be collected on the MBS and its amortized cost. The credit loss, if any, is then recognized in earnings, while the balance of impairment related to other factors is recognized in other comprehensive income. Following the recognition of an OTTI through earnings, a new cost basis is established for the security. Any subsequent recoveries in fair value may be accreted back into the amortized cost basis of the MBS on a prospective basis through interest income. Please see Note 2 for additional information related to the Company's evaluation for OTTI. Repurchase Agreements The Company's repurchase agreements, which are used to finance its purchases of MBS, are accounted for as secured borrowings under which the Company pledges its securities as collateral to secure a loan, which is equal in value to a specified percentage of the estimated fair value of the pledged collateral. The Company retains beneficial ownership of the pledged collateral. At the maturity of a repurchase agreement, the Company is required to repay the loan and concurrently receives back its pledged collateral from the lender or, with the consent of the lender, the Company may renew the agreement at the then prevailing financing rate. A repurchase agreement lender may require the Company to pledge additional collateral in the event of a decline in the fair value of the collateral pledged. Repurchase agreement financing is recourse to the Company and the assets pledged. Most of the Company’s repurchase agreements are based on the September 1996 version of the Bond Market Association Master Repurchase Agreement, which generally provides that the lender, as buyer, is responsible for obtaining collateral valuations from a generally recognized source agreed to by both the Company and the lender, or, in an instance when such source is not available, the value determination is made by the lender. Derivative Instruments The Company's derivative instruments include interest rate swaps and forward contracts for the purchase or sale of generic Agency RMBS, commonly referred to as "TBA securities" or "TBA contracts". Derivative instruments are accounted for at the fair value of their unit of account. Derivative instruments in a gain position are reported as derivative assets and derivative instruments in a loss position are reported as derivative liabilities on the Company's consolidated balance sheet. All periodic interest costs and changes in fair value of derivative instruments, including gains and losses realized upon termination, maturity, or settlement are recorded in "gain (loss) on derivative instruments, net" on the Company's consolidated statement of comprehensive income. Cash receipts and payments related to derivative instruments are classified in the investing activities section of our consolidated statements of cash flows in accordance with the underlying nature or purpose of the derivative transactions. Our interest rate swap agreements are privately negotiated in the over-the-counter ("OTC") market and the majority of these agreements are centrally cleared through the Chicago Mercantile Exchange ("CME") with the rest being subject to bilateral agreements between the Company and the swap counterparty. The Company's CME cleared swaps require that the Company post initial margin as determined by the CME, and in addition, variation margin is exchanged, typically in cash, for changes in the fair value of the CME cleared swaps. Beginning in January 2017, as a result of a change in the CME's rulebook, the exchange of variation margin for CME cleared swaps is legally considered to be the settlement of the derivative itself as opposed to a pledge of collateral. Accordingly, beginning in 2017, the Company accounts for the daily exchange of variation margin associated with its CME cleared interest rate swaps as a direct increase or decrease to the carrying value of the related derivative asset or liability. The carrying value of CME cleared interest rate swaps on the Company's consolidated balance sheets is the unsettled fair value of those instruments. A TBA security is a forward contract for the purchase or sale of a generic Agency MBS at a predetermined price 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. The Company executes TBA dollar roll transactions which effectively delay the settlement of a forward purchase of a TBA Agency RMBS by entering into an offsetting short position (referred to as a "pair off"), net settling the paired-off positions in cash, and simultaneously entering a similar TBA contract for a later settlement date. TBA securities purchased for a forward settlement month are generally priced at a discount relative to TBA securities sold for settlement in the current month. This discount, often referred to as “drop income” is the economic equivalent of net interest income on the underlying Agency securities over the roll period (interest income less implied financing cost). The Company accounts for TBA securities as derivative instruments because the Company cannot assert that it is probable at inception and throughout the term of an individual TBA contract that its settlement will result in physical delivery of the underlying Agency RMBS, or the individual TBA contract will not settle in the shortest time period possible. Please refer to Note 4 for additional information regarding the Company's derivative instruments as well as Note 5 for information on how the fair value of these instruments are calculated. Share-Based Compensation Pursuant to the Company’s 2009 Stock and Incentive Plan, the Company may grant share-based compensation to eligible employees, directors or consultants or advisers to the Company, including stock awards, stock options, stock appreciation rights, dividend equivalent rights, performance shares, and restricted stock units. The Company's restricted stock currently issued and outstanding under this plan may be settled only in shares of its common stock, and therefore are treated as equity awards with their fair value measured at the grant date and recognized as compensation cost over the requisite service period with a corresponding credit to shareholders' equity. The requisite service period is the period during which an employee is required to provide service in exchange for an award, which is equivalent to the vesting period specified in the terms of the time-based restricted stock award. None of the Company's restricted stock awards have performance based conditions. The Company does not currently have any share-based compensation issued or outstanding other than restricted stock issued to its employees, officers, and directors. Contingencies In the normal course of business, there may be various lawsuits, claims, and other contingencies pending against the Company. On a quarterly basis, the Company evaluates whether to establish provisions for estimated losses from those matters. The Company recognizes a liability for a contingent loss when: (a) the underlying causal event has occurred prior to the balance sheet date; (b) it is probable that a loss has been incurred; and (c) there is a reasonable basis for estimating that loss. A liability is not recognized for a contingent loss when it is only possible or remotely possible that a loss has been incurred, however, possible contingent losses shall be disclosed. If the contingent loss (or an additional loss in excess of any accrual) is at least a reasonable possibility and material, then the Company discloses a reasonable estimate of the possible loss or range of loss, if such reasonable estimate can be made. If the Company cannot make a reasonable estimate of the possible material loss, or range of loss, then that fact is disclosed. Recent Accounting Pronouncements The Financial Accounting Standards Board ("FASB") issued ASU No. 2017-08, Receivables-Nonrefundable Fees and Other Costs, which shortens the amortization period for certain callable debt securities held at a premium, requiring the premium to be amortized to the earliest call date. The amendments in this ASU are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018 and early adoption is permitted. The amendments in this Update should be applied using the modified-retrospective transition approach and will require disclosures for the change in accounting principle. The Company does not expect this ASU to have a material impact on the Company's consolidated financial statements. FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which contains significant amendments to hedge accounting with the main objective of better aligning an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. To meet that objective, the amendments expand and refine hedge accounting for both non-financial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. This ASU also includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness as well as changes to current disclosure requirements. The amendments in this ASU are effective for public business entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, and early adoption is permitted. All transition requirements and elections will be applied to hedging relationships existing on the date of adoption. The effect of adoption will be reflected as of the beginning of the fiscal year of adoption, and the amended presentation and disclosure guidance is required only prospectively. The Company does not currently apply hedge accounting, but is evaluating the impact this ASU would have on its consolidated financial statements if the Company elects to adopt hedge accounting in the future.

Mortgage Backed Securities (Not

Mortgage Backed Securities (Notes)	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Mortgage-backed securities	MORTGAGE-BACKED SECURITIES The majority of the Company's MBS are pledged as collateral for the Company's secured borrowings. The following tables present the Company’s MBS by investment type as of the dates indicated: September 30, 2017 Par Net Premium (Discount) Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value WAC (1) CMBS: Agency $ 1,302,237 $ 12,688 1,314,925 $ 6,187 $ (13,623 ) 1,307,489 2.99 % Non-Agency 40,780 (4,452 ) 36,328 2,877 — 39,205 5.48 % 1,343,017 8,236 1,351,253 9,064 (13,623 ) 1,346,694 CMBS IO (2) : Agency — 394,380 394,380 7,592 (164 ) 401,808 0.63 % Non-Agency — 322,735 322,735 6,254 (330 ) 328,659 0.61 % — 717,115 717,115 13,846 (494 ) 730,467 RMBS: Agency fixed-rate 522,099 19,163 541,262 — (1,903 ) 539,359 3.52 % Agency adjustable-rate 294,254 11,011 305,265 1,263 (2,746 ) 303,782 3.05 % Non-Agency 1,113 — 1,113 49 (20 ) 1,142 6.75 % 817,466 30,174 847,640 1,312 (4,669 ) 844,283 Total AFS securities: $ 2,160,483 $ 755,525 $ 2,916,008 $ 24,222 $ (18,786 ) $ 2,921,444 (1) The weighted average coupon ("WAC") is the gross interest rate of the security weighted by the outstanding principal balance (or by notional balance in the case of an IO security). (2) The notional balance for Agency CMBS IO and non-Agency CMBS IO was $14,253,392 and $11,061,377 , respectively, as of September 30, 2017 . December 31, 2016 Par Net Premium (Discount) Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value WAC (1) CMBS: Agency $ 1,152,586 $ 13,868 $ 1,166,454 $ 6,209 $ (28,108 ) $ 1,144,555 3.12 % Non-Agency 79,467 (6,718 ) 72,749 5,467 — 78,216 4.72 % 1,232,053 7,150 1,239,203 11,676 (28,108 ) 1,222,771 CMBS IO (2) : Agency — 411,737 411,737 3,523 (3,362 ) 411,898 0.67 % Non-Agency — 346,155 346,155 1,548 (5,055 ) 342,648 0.61 % — 757,892 757,892 5,071 (8,417 ) 754,546 RMBS: Agency adjustable-rate $ 1,157,258 $ 57,066 $ 1,214,324 $ 2,832 $ (15,951 ) $ 1,201,205 3.05 % Non-Agency 33,572 (24 ) 33,548 64 (50 ) 33,562 3.58 % 1,190,830 57,042 1,247,872 2,896 (16,001 ) 1,234,767 Total AFS securities: $ 2,422,883 $ 822,084 $ 3,244,967 $ 19,643 $ (52,526 ) $ 3,212,084 (1) The WAC is the gross interest rate of the pool of mortgages underlying the security weighted by the outstanding principal balance (or by notional balance in the case of an IO security). (2) The notional balance for the Agency CMBS IO and non-Agency CMBS IO was $13,106,912 and $10,884,964 , respectively, as of December 31, 2016 . Actual maturities of MBS are affected by the contractual lives of the underlying mortgage collateral, periodic payments of principal, prepayments of principal, and the payment priority structure of the security; therefore, actual maturities are generally shorter than the securities' stated contractual maturities. The following table presents information regarding the sales included in "loss on sale of investments, net" on the Company's consolidated statements of comprehensive income for the periods indicated: Three Months Ended September 30, 2017 2016 Proceeds Received Realized Gain (Loss) Proceeds Received Realized Gain (Loss) Agency RMBS $ 393,502 $ (5,160 ) $ — $ — Agency CMBS 13,433 (51 ) — — $ 406,935 $ (5,211 ) $ — $ — Nine Months Ended September 30, 2017 2016 Proceeds Received Realized Gain (Loss) Proceeds Received Realized Gain (Loss) Agency RMBS $ 716,560 $ (12,392 ) $ 54,178 $ (3,010 ) Agency CMBS 206,993 523 — — Non-Agency CMBS 35,705 1,199 33,640 (1,228 ) Non-Agency RMBS 16,407 42 — — $ 975,665 $ (10,628 ) $ 87,818 $ (4,238 ) The following table presents certain information for those MBS in an unrealized loss position as of the dates indicated: September 30, 2017 December 31, 2016 Fair Value Gross Unrealized Losses # of Securities Fair Value Gross Unrealized Losses # of Securities Continuous unrealized loss position for less than 12 months: Agency MBS $ 1,377,438 $ (13,201 ) 76 $ 1,738,094 $ (38,469 ) 133 Non-Agency MBS 38,979 (151 ) 6 205,484 (2,773 ) 48 Continuous unrealized loss position for 12 months or longer: Agency MBS $ 206,045 $ (5,236 ) 17 $ 427,405 $ (8,952 ) 72 Non-Agency MBS 15,749 (199 ) 11 81,660 (2,332 ) 26 Because the principal related to Agency MBS is guaranteed by the government-sponsored entities Fannie Mae and Freddie Mac which have the implicit guarantee of the U.S. government, the Company does not consider any of the unrealized losses on its Agency MBS to be credit related. Although the unrealized losses are not credit related, the Company assesses its ability and intent to hold any Agency MBS with an unrealized loss until the recovery in its value in accordance with GAAP. This assessment is based on the amount of the unrealized loss and significance of the related investment as well as the Company’s leverage and liquidity position. Based on this analysis, the Company has determined that the unrealized losses on its Agency MBS as of September 30, 2017 and December 31, 2016 were temporary. The Company reviews any non-Agency MBS in an unrealized loss position to evaluate whether any decline in fair value represents an OTTI. The evaluation includes a review of the credit ratings of the non-Agency MBS, the credit characteristics of the mortgage loans collateralizing these securities, and the estimated future cash flows including projected collateral losses. The Company performed this evaluation for its non-Agency MBS in an unrealized loss position and has determined that there have not been any adverse changes in the timing or amount of estimated future cash flows that necessitate a recognition of OTTI amounts as of September 30, 2017 or December 31, 2016 .

Repurchase Agreements (Notes)

Repurchase Agreements (Notes)	9 Months Ended
	Sep. 30, 2017
Disclosure of Repurchase Agreements [Abstract]
Repurchase agreements	REPURCHASE AGREEMENTS The Company’s repurchase agreements outstanding as of September 30, 2017 and December 31, 2016 are summarized in the following tables: September 30, 2017 December 31, 2016 Collateral Type Balance Weighted Average Rate Fair Value of Collateral Pledged Balance Weighted Average Rate Fair Value of Collateral Pledged Agency CMBS $ 1,188,230 1.31 % $ 1,250,575 $ 1,005,726 0.82 % $ 1,095,002 Non-Agency CMBS 15,625 2.14 % 18,365 66,881 1.63 % 77,840 Agency CMBS IO 336,187 2.06 % 389,637 346,892 1.57 % 407,481 Non-Agency CMBS IO 279,981 2.15 % 327,976 291,199 1.67 % 341,139 Agency RMBS 695,841 1.31 % 727,727 1,157,302 0.82 % 1,191,147 Non-Agency RMBS — — % — 26,149 1.98 % 31,952 Securitization financing bond 3,366 2.58 % 3,723 4,803 2.00 % 5,278 Total repurchase agreements $ 2,519,230 1.51 % $ 2,718,003 $ 2,898,952 1.03 % $ 3,149,839 The following table provides information on the remaining term to maturity and original term to maturity for the Company's repurchase agreements as of the periods indicated: September 30, 2017 December 31, 2016 Remaining Term to Maturity Balance WAVG Original Term to Maturity Balance WAVG Original Term to Maturity Less than 30 days $ 1,725,518 36 $ 2,480,213 58 30 to 90 days 793,712 89 418,739 87 Total $ 2,519,230 53 $ 2,898,952 63 The following table lists the counterparties with whom the Company had over 10% of its shareholders' equity at risk (defined as the excess of collateral pledged over the borrowings outstanding): September 30, 2017 Counterparty Name Balance Weighted Average Rate Equity at Risk Wells Fargo Bank, N. A. and affiliates $ 349,965 2.10 % $ 57,992 Of the amount outstanding with Wells Fargo Bank, N.A. and affiliates, $343,780 is under a committed repurchase facility which has an aggregate maximum borrowing capacity of $400,000 and is scheduled to mature on May 12, 2019, subject to early termination provisions contained in the master repurchase agreement. The facility is collateralized primarily by CMBS IO, and its weighted average borrowing rate as of September 30, 2017 was 2.10% . As of September 30, 2017 , the Company had repurchase agreement amounts outstanding with 18 of its 34 available repurchase agreement counterparties. The Company's counterparties, as set forth in the master repurchase agreement with the counterparty, require the Company to comply with various customary operating and financial covenants, including, but not limited to, minimum net worth and earnings, maximum declines in net worth in a given period, and maximum leverage requirements as well as maintaining the Company's REIT status. In addition, some of the agreements contain cross default features, whereby default under an agreement with one lender simultaneously causes default under agreements with other lenders. To the extent that the Company fails to comply with the covenants contained in these financing agreements or is otherwise found to be in default under the terms of such agreements, the counterparty has the right to accelerate amounts due under the master repurchase agreement. The Company was in full compliance with all covenants as of September 30, 2017 . The Company's repurchase agreements are subject to underlying agreements with master netting or similar arrangements, which provide for the right of offset in the event of default or in the event of bankruptcy of either party to the transactions. The Company reports its repurchase agreements to these arrangements on a gross basis. The following tables present information regarding the Company's repurchase agreements as if the Company had presented them on a net basis as of September 30, 2017 and December 31, 2016: Gross Amount of Recognized Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (1) Net Amount Financial Instruments Posted as Collateral Cash Posted as Collateral September 30, 2017 Repurchase agreements $ 2,519,230 $ — $ 2,519,230 $ (2,519,230 ) $ — $ — December 31, 2016: Repurchase agreements $ 2,898,952 $ — $ 2,898,952 $ (2,898,952 ) $ — $ — (1) Amounts disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented. Please see Note 4 for information related to the Company's derivatives which are also subject to underlying agreements with master netting or similar arrangements.

Derivatives (Notes)

Derivatives (Notes)	9 Months Ended
	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	DERIVATIVES The Company's derivative instruments include interest rate swaps and TBA securities. The Company utilizes interest rate swaps to economically hedge a portion of its exposure to interest rate risk in order to mitigate declines in book value resulting from fluctuations in the fair value of the Company's assets from changing interest rates and to protect some portion of the Company's earnings from rising interest rates. The Company invests in TBA securities for the purchase or sale of Agency RMBS on a non-specified pool basis. TBA securities are forward contracts which are accounted for as derivative instruments; however, management views TBA securities as the economic equivalent of investing in and financing generic Agency fixed-rate RMBS through the repurchase agreement markets. Please refer to Note 1 for information related to the Company's accounting policy for its derivative instruments. The table below summarizes information about the fair value by type of derivative instrument on the Company's consolidated balance sheets as of the dates indicated: September 30, 2017 December 31, 2016 Type of Derivative Instruments Balance Sheet Location Fair Value Fair Value (1) Interest rate swaps Derivative assets $ 368 $ 28,534 TBA securities Derivative assets — — $ 368 $ 28,534 Interest rate swaps Derivative liabilities $ — $ (6,922 ) TBA securities Derivative liabilities (133 ) — $ (133 ) $ (6,922 ) (1) Refer to Note 1 regarding information on a change in the CME rulebook. Amounts reported on the consolidated balance sheet as of September 30, 2017 for its interest rate swaps reflect the netting of the derivative asset or liability with the related collateral received or posted, respectively. The net amounts comparable to September 30, 2017 for the derivative asset and derivative liabilities as of December 31, 2016 were $104 and $(576) , respectively. The following tables present information about the Company's interest rate swaps as of the dates indicated: September 30, 2017 Weighted-Average: Years to Maturity: Net Notional Amount (1) Pay Rate (2) Life Remaining (in Years) Fair Value < 3 years $ 3,110,000 1.39 % 0.9 $ 368 >3 and < 6 years 1,160,000 1.66 % 4.2 — >6 and < 10 years 1,175,000 2.45 % 8.1 — Total $ 5,445,000 1.68 % 3.2 $ 368 December 31, 2016 Weighted-Average: Years to Maturity: Net Notional Amount (1) Pay Rate (2) Life Remaining (in Years) Fair Value < 3 years $ 595,000 0.73 % 2.3 $ 4,348 >3 and < 6 years 1,185,000 1.47 % 4.3 8,631 >6 and < 10 years 1,250,000 2.42 % 8.9 8,633 Total $ 3,030,000 1.58 % 5.3 $ 21,612 (1) The net notional amounts included in the tables above represent pay-fixed interest rate swaps, net of receive-fixed interest rate swaps and include $2,425,000 and $2,725,000 of pay-fixed forward starting interest rate swaps as of September 30, 2017 and December 31, 2016 , respectively. (2) Excluding forward starting pay-fixed interest rate swaps, the weighted average pay rate was 1.34% and 0.73% as of September 30, 2017 and December 31, 2016, respectively. The following table summarizes information about the Company's TBA securities as of September 30, 2017 : September 30, 2017 Notional Amount (1) Cost Basis (2) Market Value (3) Net Carrying Value (4) 30-year 4.0% TBA securities $ 650,000 $ 683,813 $ 683,680 $ (133 ) (1) Notional amount represents the par value (or principal balance) of the underlying Agency MBS. (2) Cost basis represents the forward price to be paid for the underlying Agency MBS as if settled. (3) Market value is the current fair value of the TBA contract and represents the estimated fair value of the underlying Agency security as of the end of the period. (4) Net carrying value represents the difference between the market value and the cost basis of the TBA contract as of the end of the period and is included on the consolidated balance sheets within "derivative assets (liabilities)". The tables below summarize changes in our derivative instruments for the periods indicated: Type of Derivative Instrument Notional Amount as of December 31, 2016 Additions Settlements, Terminations, or Pair-Offs Notional Amount as of September 30, 2017 Receive-fixed interest rate swaps $ 425,000 $ — $ (325,000 ) $ 100,000 Pay-fixed interest rate swaps 3,455,000 3,010,000 (920,000 ) 5,545,000 TBA securities — 3,814,000 (3,164,000 ) 650,000 The table below provides detail of the Company's "gain (loss) on derivative instruments, net" by type of derivative for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, Type of Derivative Instrument 2017 2016 2017 2016 Receive-fixed interest rate swaps $ (99 ) $ (2,976 ) $ 746 $ 11,301 Pay-fixed interest rate swaps (611 ) 2,555 (18,799 ) (59,912 ) TBA securities 6,703 — 8,419 — Eurodollar futures — 2,830 — (13,542 ) Gain (loss) on derivative instruments, net $ 5,993 $ 2,409 $ (9,634 ) $ (62,153 ) There is a net unrealized gain of $450 remaining in AOCI on the Company's consolidated balance sheet as of September 30, 2017 which represents the activity related to interest rate swap agreements while they were previously designated as cash flow hedges, and this amount will be recognized in the Company's net income as an adjustment to "interest expense" over the remaining contractual life of the agreements. The Company estimates a credit of $210 will be reclassified to net income as a reduction of "interest expense" within the next 12 months. A portion of the Company's interest rate swaps were entered into under bilateral agreements which contain cross-default provisions with other agreements between the parties. In addition, these bilateral agreements contain financial and operational covenants similar to those contained in our repurchase agreements as described in Note 3 . The Company was in compliance with all covenants with respect to bilateral agreements under which interest rate swaps were entered into as of September 30, 2017 . The Company's derivatives are subject to underlying agreements with master netting or similar arrangements, which provide for the right of offset in the event of default or in the event of bankruptcy of either party to the transactions. The Company reports its derivative assets and liabilities subject to these arrangements on a gross basis. The following tables present information regarding those derivative assets and liabilities subject to such arrangements as if the Company had presented them on a net basis as of September 30, 2017 and December 31, 2016: Offsetting of Assets Gross Amount of Recognized Assets Gross Amount Offset in the Balance Sheet Net Amount of Assets Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (1) Net Amount Financial Instruments Received as Collateral Cash Received as Collateral September 30, 2017 Interest rate swaps $ 368 $ — $ 368 $ — $ — $ 368 TBA securities — — — — — — Derivative assets $ 368 $ — $ 368 $ — $ — $ 368 December 31, 2016: Interest rate swaps $ 28,534 $ — $ 28,534 $ (6,449 ) $ (22,085 ) $ — TBA securities — — — — — — Derivative assets $ 28,534 $ — $ 28,534 $ (6,449 ) $ (22,085 ) $ — Offsetting of Liabilities Gross Amount of Recognized Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (1) Net Amount Financial Instruments Posted as Collateral Cash Posted as Collateral September 30, 2017 Interest rate swaps $ — $ — $ — $ — $ — $ — TBA securities 133 — 133 — (63 ) 70 Derivative liabilities $ 133 $ — $ 133 $ — $ (63 ) $ 70 December 31, 2016: Interest rate swaps $ 6,922 $ — $ 6,922 $ (6,913 ) $ — $ 9 TBA securities — — — — — — Derivative liabilities $ 6,922 $ — $ 6,922 $ (6,913 ) $ — $ 9 (1) Amounts disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented. Please see Note 3 for information related to the Company's repurchase agreements which are also subject to underlying agreements with master netting or similar arrangements.

Fair Value of Financial Instrum

Fair Value of Financial Instruments (Notes)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	FAIR VALUE OF FINANCIAL INSTRUMENTS ASC Topic 820 defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC Topic 820 clarifies that fair value should be based on the assumptions market participants would use when pricing an asset or liability and also requires an entity to consider all aspects of nonperformance risk, including the entity's own credit standing, when measuring fair value of a liability. ASC Topic 820 established a valuation hierarchy of three levels as follows: • Level 1 – Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities as of the measurement date. • Level 2 – Inputs include quoted prices in active markets for similar assets or liabilities; quoted prices in inactive markets for identical or similar assets or liabilities; or inputs either directly observable or indirectly observable through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life. • Level 3 – Unobservable inputs are supported by little or no market activity. The unobservable inputs represent management’s best estimate of how market participants would price the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. The Company reviews the classification of its financial instruments within the fair value hierarchy on a quarterly basis, and management may conclude that its financial instruments should be reclassified to a different level in the future if a change in type of inputs occurs. The following table presents the fair value of the Company’s financial instruments segregated by the hierarchy level of the fair value estimate that are measured at fair value on a recurring basis as of the dates indicated: September 30, 2017 Fair Value Level 1 - Unadjusted Quoted Prices in Active Markets Level 2 - Observable Inputs Level 3 - Unobservable Inputs Assets: Mortgage-backed securities $ 2,921,444 $ — $ 2,913,877 $ 7,567 Interest rate swaps 368 — 368 — Total assets carried at fair value $ 2,921,812 $ — $ 2,914,245 $ 7,567 Liabilities: TBA securities 133 — 133 — Total liabilities carried at fair value $ 133 $ — $ 133 $ — December 31, 2016 Fair Value Level 1 - Unadjusted Quoted Prices in Active Markets Level 2 - Observable Inputs Level 3 - Unobservable Inputs Assets: Mortgage-backed securities $ 3,212,084 $ — $ 3,201,157 $ 10,927 Interest rate swaps 28,534 — 28,534 — Total assets carried at fair value $ 3,240,618 $ — $ 3,229,691 $ 10,927 Liabilities: Interest rate swaps $ 6,922 $ — $ 6,922 $ — Total liabilities carried at fair value $ 6,922 $ — $ 6,922 $ — The fair value measurements for a majority of the Company's MBS are considered Level 2. These Level 2 securities are substantially similar to securities that either are actively traded or have been recently traded in their respective markets. The Company determines the fair value of its Level 2 securities based on prices received from the Company's primary pricing service as well as other pricing services and brokers. The Company evaluates the third party prices it receives to assess their reasonableness. Although the Company does not adjust third party prices, they may be excluded from use in the determination of a security's fair value if they are significantly different from other observable market data. In valuing a security, the primary pricing service uses either a market approach, which uses observable prices and other relevant information that is generated by market transactions of identical or similar securities, or an income approach, which uses valuation techniques to convert future amounts to a single, discounted present value amount. The Company also reviews the assumptions and inputs utilized in the valuation techniques of its primary pricing service. Examples of these observable inputs and assumptions include market interest rates, credit spreads, and projected prepayment speeds, among other things. The fair value of interest rate swaps are measured using the income approach with the primary input being the forward interest rate swap curve, which is considered an observable input, and thus their fair values are considered Level 2 measurements as of September 30, 2017 and December 31, 2016. The fair value of TBA securities are estimated using methods similar those used to fair value the Company's Level 2 MBS. The Company owns certain non-Agency MBS for which there are not sufficiently recent trades of substantially similar securities, and their fair value measurements are thus considered Level 3. The Company determines the fair value of its Level 3 securities by discounting the estimated future cash flows derived from cash flow models using significant inputs which are determined by the Company when market observable inputs are not available. Information utilized in those pricing models include the security’s credit rating, coupon rate, estimated prepayment speeds, expected weighted average life, collateral composition, estimated future interest rates, expected credit losses, and credit enhancement as well as certain other relevant information. Significant changes in any of these inputs in isolation may result in a significantly different fair value measurement. Level 3 assets are generally most sensitive to the default rate and severity assumptions. The activity of the instruments measured at fair value on a recurring basis using Level 3 inputs is presented in the following table for the period indicated: Level 3 Fair Value Non-Agency CMBS Non-Agency RMBS Total Balance as of December 31, 2016 $ 9,669 $ 1,258 $ 10,927 Unrealized loss included in OCI (1) (1,422 ) 16 (1,406 ) Principal payments (3,896 ) (133 ) (4,029 ) Accretion 2,075 — 2,075 Balance as of September 30, 2017 $ 6,426 $ 1,141 $ 7,567 (1) Amount included in "unrealized gain on available-for-sale investments, net" on consolidated statements of comprehensive income (loss). The following table presents a summary of the carrying value and estimated fair values of the Company’s financial instruments as of the dates indicated: September 30, 2017 December 31, 2016 Carrying Value Fair Value Carrying Value Fair Value Assets: Mortgage-backed securities $ 2,921,444 $ 2,921,444 $ 3,212,084 $ 3,212,084 Mortgage loans held for investment, net (1) 16,523 13,674 19,036 15,971 Derivative assets 368 368 28,534 28,534 Liabilities: Repurchase agreements (2) $ 2,519,230 $ 2,519,230 $ 2,898,952 $ 2,898,952 Non-recourse collateralized financing (1) 5,706 5,722 6,440 6,357 Derivative liabilities 133 133 6,922 6,922 (1) The Company determines the fair value of its mortgage loans held for investment, net and its non-recourse collateralized financing using internally developed cash flow models with inputs similar to those used to estimate the fair value of the Company's Level 3 non-Agency MBS. (2) The carrying value of repurchase agreements generally approximates fair value due to their short term maturities.

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Shareholders' Equity	SHAREHOLDERS' EQUITY AND SHARE-BASED COMPENSATION Preferred Stock The Company's articles of incorporation authorize the issuance of up to 50,000,000 shares of preferred stock, par value $0.01 per share, of which the Company's Board of Directors has designated 8,000,000 shares of 8.50% Series A Preferred Stock and 7,000,000 shares of 7.625% Series B Preferred Stock, (the Series A Preferred Stock and the Series B Preferred Stock collectively, the "Preferred Stock"). The Company had 2,300,000 shares of its Series A Preferred Stock and 3,365,101 shares of its Series B Preferred Stock issued and outstanding as of September 30, 2017 compared to 2,300,000 shares of Series A Preferred Stock and 2,271,937 shares of Series B Preferred Stock as of December 31, 2016. The Preferred Stock has no maturity and will remain outstanding indefinitely unless redeemed or otherwise repurchased or converted into common stock pursuant to the terms of the Preferred Stock. The Company's Series A Preferred Stock may be redeemed in whole, or in part, at any time and from time to time at the Company's option at a cash redemption price of $25.00 per share plus any accumulated and unpaid dividends. Except under certain limited circumstances, the Company may not redeem the Series B Preferred Stock prior to April 30, 2018. On or after April 30, 2018, the Company's Series B Preferred Stock may be redeemed in whole, or in part, at any time and from time to time at the Company's option at a cash redemption price of $25.00 per share plus any accumulated and unpaid dividends. Because the Preferred Stock is redeemable only at the option of the issuer, it is classified as equity on the Company's consolidated balance sheet. The Series A Preferred Stock pays a cumulative cash dividend equivalent to 8.50% of the $25.00 liquidation preference per share each year and the Series B Preferred Stock pays a cumulative cash dividend equivalent to 7.625% of the $25.00 liquidation preference per share each year. The Company paid its regular quarterly dividends on its Preferred Stock for the third quarter on October 16, 2017 to shareholders of record as of October 1, 2017 . Common Stock The Company declared a third quarter common stock dividend of $0.18 per share that was paid on October 31, 2017 to shareholders of record as of October 3, 2017 . 2009 Stock and Incentive Plan. Of the 2,500,000 shares of common stock authorized for issuance under its 2009 Stock and Incentive Plan, the Company had 785,962 available for issuance as of September 30, 2017 . Total stock-based compensation expense recognized by the Company for the three and nine months ended September 30, 2017 was $388 and $1,567 , respectively, compared to $623 and $2,066 for the three and nine months ended September 30, 2016 , respectively. The following table presents a rollforward of the restricted stock activity for the periods indicated: Three Months Ended September 30, 2017 2016 Shares Weighted Average Grant Date Fair Value Per Share Shares Weighted Average Grant Date Fair Value Per Share Restricted stock outstanding as of beginning of period 353,103 $ 7.01 561,089 $ 7.54 Restricted stock granted — — — — Restricted stock vested — — — — Restricted stock outstanding as of end of period 353,103 $ 7.01 561,089 $ 7.54 Nine Months Ended September 30, 2017 2016 Shares Weighted Average Grant Date Fair Value Per Share Shares Weighted Average Grant Date Fair Value Per Share Restricted stock outstanding as of beginning of period 553,396 $ 7.55 696,597 $ 8.54 Restricted stock granted 138,166 6.76 214,878 6.28 Restricted stock vested (338,459 ) 7.80 (350,386 ) 8.76 Restricted stock outstanding as of end of period 353,103 $ 7.01 561,089 $ 7.54 As of September 30, 2017 , the grant date fair value of the Company’s remaining nonvested restricted stock is $1,505 which will be amortized into compensation expense over a weighted average period of 1.5 years .
Preferred Stock	Preferred Stock The Company's articles of incorporation authorize the issuance of up to 50,000,000 shares of preferred stock, par value $0.01 per share, of which the Company's Board of Directors has designated 8,000,000 shares of 8.50% Series A Preferred Stock and 7,000,000 shares of 7.625% Series B Preferred Stock, (the Series A Preferred Stock and the Series B Preferred Stock collectively, the "Preferred Stock"). The Company had 2,300,000 shares of its Series A Preferred Stock and 3,365,101 shares of its Series B Preferred Stock issued and outstanding as of September 30, 2017 compared to 2,300,000 shares of Series A Preferred Stock and 2,271,937 shares of Series B Preferred Stock as of December 31, 2016. The Preferred Stock has no maturity and will remain outstanding indefinitely unless redeemed or otherwise repurchased or converted into common stock pursuant to the terms of the Preferred Stock. The Company's Series A Preferred Stock may be redeemed in whole, or in part, at any time and from time to time at the Company's option at a cash redemption price of $25.00 per share plus any accumulated and unpaid dividends. Except under certain limited circumstances, the Company may not redeem the Series B Preferred Stock prior to April 30, 2018. On or after April 30, 2018, the Company's Series B Preferred Stock may be redeemed in whole, or in part, at any time and from time to time at the Company's option at a cash redemption price of $25.00 per share plus any accumulated and unpaid dividends. Because the Preferred Stock is redeemable only at the option of the issuer, it is classified as equity on the Company's consolidated balance sheet. The Series A Preferred Stock pays a cumulative cash dividend equivalent to 8.50% of the $25.00 liquidation preference per share each year and the Series B Preferred Stock pays a cumulative cash dividend equivalent to 7.625% of the $25.00 liquidation preference per share each year. The Company paid its regular quarterly dividends on its Preferred Stock for the third quarter on October 16, 2017 to shareholders of record as of October 1, 2017 .

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Management has evaluated events and circumstances occurring as of and through the date this Quarterly Report on Form 10-Q was filed with the SEC and made available to the public and has determined that there have been no significant events or circumstances that qualify as a "recognized" subsequent event as defined by ASC Topic 855. Management has determined that the following significant event, which occurred subsequent to September 30, 2017 and before the date this Quarterly Report on Form 10-Q was filed with the SEC and made available to the public, qualifies as a "nonrecognized" subsequent event as defined by ASC Topic 855: The Company has received $14,078 in net proceeds from at-the-market issuances of 1,956,936 shares of its common stock since September 30, 2017 and $2,169 in net proceeds from at-the-market issuance of 89,313 shares of Series B Preferred Stock.

Organization and Summary of S14

Organization and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Organization [Text Block]	Organization Dynex Capital, Inc., ("Company") was incorporated in the Commonwealth of Virginia on December 18, 1987 and commenced operations in February 1988. The Company primarily earns income from investing on a leveraged basis in specified pools of Agency and non-Agency mortgage-backed securities (“MBS”) consisting of residential MBS (“RMBS”), commercial MBS (“CMBS”) and CMBS interest-only ("IO") securities that are issued or guaranteed by the U.S. Government or U.S. Government sponsored agencies ("Agency MBS") and MBS issued by others ("non-Agency MBS"). We also invest in other types of mortgage-related securities, such as to-be-announced (“TBA”) forward contracts for the purchase or sale of generic (also referred to as "non-specified") pools of Agency MBS.
Basis of Presentation [Policy Text Block]	Basis of Presentation The accompanying unaudited consolidated financial statements of Dynex Capital, Inc. and its subsidiaries (together, “Dynex” or, as appropriate, the “Company”) have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and with the instructions to the Quarterly Report on Form 10-Q and Article 10, Rule 10-01 of Regulation S-X promulgated by the Securities and Exchange Commission (the “SEC”). Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all significant adjustments, consisting of normal recurring accruals, considered necessary for a fair presentation of the consolidated financial statements have been included. Operating results for the three months ended September 30, 2017 are not necessarily indicative of the results that may be expected for any other interim periods or for the entire year ending December 31, 2017. The unaudited consolidated financial statements included herein should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 filed with the SEC.
Consolidation [Policy Text Block]	Consolidation The consolidated financial statements include the accounts of the Company and the accounts of its majority owned subsidiaries and variable interest entities ("VIE") for which it is the primary beneficiary. As a primary beneficiary, the Company has both the power to direct the activities that most significantly impact the economic performance of the VIE and a right to receive benefits or absorb losses of the entity that could be potentially significant to the VIE. The Company is required to reconsider its evaluation of whether to consolidate a VIE each reporting period, based upon changes in the facts and circumstances pertaining to the VIE. The Company consolidates certain trusts through which it has securitized mortgage loans as a result of not meeting the sale criteria under GAAP at the time the financial assets were transferred to the trust. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates [Policy Text Block]	Use of Estimates 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 the disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of revenue and expenses during the reported period. Actual results could differ from those estimates. The most significant estimates used by management include, but are not limited to, amortization of premiums and discounts, fair value measurements of its investments, and other-than-temporary impairments. These items are discussed further below within this note to the consolidated financial statements.
Income Taxes [Policy Text Block]	Income Taxes The Company has elected to be taxed as a real estate investment trust ("REIT") under the Internal Revenue Code of 1986 and the corresponding provisions of state law. To qualify as a REIT, the Company must meet certain tests including investing in primarily real estate-related assets and the required distribution of at least 90% of its annual REIT taxable income to stockholders after consideration of its net operating loss ("NOL") carryforward and not including taxable income retained in its taxable subsidiaries. As a REIT, the Company generally will not be subject to federal income tax on the amount of its income or capital gains that is distributed as dividends to shareholders. The Company assesses its tax positions for all open tax years and determines whether the Company has any material unrecognized liabilities in accordance with Accounting Standards Codification ("ASC") Topic 740. The Company records these liabilities, if any, to the extent they are deemed more likely than not to have been incurred.
Net Income (Loss) Per Common Share [Text Block]	Net Income (Loss) Per Common Share The Company calculates basic net income (loss) per common share by dividing net income (loss) to common shareholders for the period by weighted-average shares of common stock outstanding for that period. The Company did not have any potentially dilutive securities outstanding during the three or nine months ended September 30, 2017 or September 30, 2016 . Holders of unvested shares of the Company's issued and outstanding restricted common stock are eligible to receive non-forfeitable dividends. As such, these unvested shares are considered participating securities as per ASC Topic 260-10 and therefore are included in the computation of basic net income (loss) per common share using the two-class method. Upon vesting, restrictions on transfer expire on each share of restricted stock, and each such share of restricted stock represents one unrestricted share of common stock. Because the Company's 8.50% Series A Cumulative Redeemable Preferred Stock (the “Series A Preferred Stock”) and 7.625% Series B Cumulative Redeemable Preferred Stock (the “Series B Preferred Stock”) are redeemable at the Company's option for cash only and may convert into shares of common stock only upon a change of control of the Company, the effect of those shares and their related dividends is excluded from the calculation of diluted net income (loss) per common share.
Cash and Cash Equivalents [Policy Text Block]	Cash and Cash Equivalents Cash and cash equivalents include cash on hand and highly liquid investments with original maturities of three months or less.
Restricted Cash [Policy Text Block]	Restricted Cash Restricted cash consists of cash the Company has pledged to cover initial and variation margin with its financing and derivative counterparties. The Company early adopted Accounting Standards Update ("ASU") No. 2016-18, Statement of Cash Flows (Topic 230) - Restricted Cash , which requires amounts generally described as restricted cash or restricted cash equivalents to be included with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the statement of cash flows. Because this ASU is to be applied retrospectively to each period presented, "net cash and cash equivalents used in financing activities" on the Company's consolidated statement of cash flows for the nine months ended September 30, 2016 now omits "increase in restricted cash" previously reported in the Quarterly Report on Form 10-Q for that period, and that increase is now included within "net increase in cash, cash equivalents, and restricted cash" for that period in order to conform to the current period's presentation. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported on the Company's consolidated balance sheet as of September 30, 2017 that sum to the total of the same such amounts shown on the Company's consolidated statement of cash flows for the nine months ended September 30, 2017 : September 30, 2017 Cash and cash equivalents $ 117,702 Restricted cash 43,987 Total cash, cash equivalents, and restricted cash shown on consolidated statement of cash flows $ 161,689
Mortgage-Backed Securities [Policy Text Block]	Mortgage-Backed Securities The Company's investments in Agency and non-Agency RMBS, CMBS, and CMBS IO securities are designated as available-for-sale ("AFS") and are recorded at fair value on the Company's consolidated balance sheet. Changes in unrealized gain (loss) on the Company's MBS are reported in other comprehensive income ("OCI") until it is sold, matures, or is determined to be other than temporarily impaired. Although the Company generally intends to hold its AFS securities until maturity, it may sell any of these securities as part of the overall management of its business. Upon the sale of an AFS security, any unrealized gain or loss is reclassified out of accumulated other comprehensive income ("AOCI") into net income as a realized "gain (loss) on sale of investments, net" using the specific identification method. The Company’s MBS pledged as collateral against repurchase agreements and derivative instruments are included in MBS on the consolidated balance sheets with the fair value of the MBS pledged as collateral disclosed parenthetically. Interest Income, Premium Amortization, and Discount Accretion. Interest income on MBS is accrued based on the outstanding principal balance (or notional balance in the case of interest-only, or "IO", securities) and their contractual terms. Premiums and discounts on the Company's Agency MBS as well as any non-Agency MBS rated 'AA' and higher at the time of purchase are amortized or accreted into interest income over the expected life of such securities using the effective yield method, and adjustments to premium amortization and discount accretion are made for actual cash payments. The Company may also adjust premium amortization and discount accretion for changes in projected future cash payments. The Company's projections of future cash payments are based on input and analysis received from external sources and internal models, and include assumptions about the amount and timing of loan prepayment rates, fluctuations in interest rates, credit losses, and other factors. On at least a quarterly basis, the Company reviews and makes any necessary adjustments to its cash flow projections and updates the yield recognized on these assets. The Company does not estimate future prepayments on its fixed-rate Agency RMBS. The Company holds certain non-Agency MBS that had credit ratings of less than 'AA' at the time of purchase or were not rated by any of the nationally recognized credit rating agencies. A portion of these non-Agency MBS were purchased at discounts to their par value, which management does not believe to be substantial. The discount is accreted into income over the security's expected life based on management's estimate of the security's projected cash flows. Future changes in the timing of projected cash flows or differences arising between projected cash flows and actual cash flows received may result in a prospective change in the effective yield on those securities. Determination of MBS Fair Value. The Company estimates the fair value of the majority of its MBS based upon prices obtained from third-party pricing services and broker quotes. The remainder of the Company's MBS are valued by discounting the estimated future cash flows derived from cash flow models that utilize information such as the security's coupon rate, estimated prepayment speeds, expected weighted average life, collateral composition, estimated future interest rates, expected losses, and credit enhancements as well as certain other relevant information. Refer to Note 5 for further discussion of MBS fair value measurements. Other-than-Temporary Impairment. An MBS is considered impaired when its fair value is less than its amortized cost. The Company evaluates all of its impaired MBS for other-than-temporary impairments ("OTTI") on at least a quarterly basis. An impairment is considered other-than-temporary if: (1) the Company intends to sell the MBS; (2) it is more likely than not that the Company will be required to sell the MBS before its fair value recovers; or (3) the Company does not expect to recover the full amortized cost basis of the MBS. If either of the first two conditions is met, the entire amount of the impairment is recognized in earnings. If the impairment is solely due to the inability to fully recover the amortized cost basis, the security is further analyzed to quantify any credit loss, which is the difference between the present value of cash flows expected to be collected on the MBS and its amortized cost. The credit loss, if any, is then recognized in earnings, while the balance of impairment related to other factors is recognized in other comprehensive income. Following the recognition of an OTTI through earnings, a new cost basis is established for the security. Any subsequent recoveries in fair value may be accreted back into the amortized cost basis of the MBS on a prospective basis through interest income. Please see Note 2 for additional information related to the Company's evaluation for OTTI.
Repurchase Agreements [Policy Text Block]	Repurchase Agreements The Company's repurchase agreements, which are used to finance its purchases of MBS, are accounted for as secured borrowings under which the Company pledges its securities as collateral to secure a loan, which is equal in value to a specified percentage of the estimated fair value of the pledged collateral. The Company retains beneficial ownership of the pledged collateral. At the maturity of a repurchase agreement, the Company is required to repay the loan and concurrently receives back its pledged collateral from the lender or, with the consent of the lender, the Company may renew the agreement at the then prevailing financing rate. A repurchase agreement lender may require the Company to pledge additional collateral in the event of a decline in the fair value of the collateral pledged. Repurchase agreement financing is recourse to the Company and the assets pledged. Most of the Company’s repurchase agreements are based on the September 1996 version of the Bond Market Association Master Repurchase Agreement, which generally provides that the lender, as buyer, is responsible for obtaining collateral valuations from a generally recognized source agreed to by both the Company and the lender, or, in an instance when such source is not available, the value determination is made by the lender.
Derivative Instruments [Policy Text Block]	Derivative Instruments The Company's derivative instruments include interest rate swaps and forward contracts for the purchase or sale of generic Agency RMBS, commonly referred to as "TBA securities" or "TBA contracts". Derivative instruments are accounted for at the fair value of their unit of account. Derivative instruments in a gain position are reported as derivative assets and derivative instruments in a loss position are reported as derivative liabilities on the Company's consolidated balance sheet. All periodic interest costs and changes in fair value of derivative instruments, including gains and losses realized upon termination, maturity, or settlement are recorded in "gain (loss) on derivative instruments, net" on the Company's consolidated statement of comprehensive income. Cash receipts and payments related to derivative instruments are classified in the investing activities section of our consolidated statements of cash flows in accordance with the underlying nature or purpose of the derivative transactions. Our interest rate swap agreements are privately negotiated in the over-the-counter ("OTC") market and the majority of these agreements are centrally cleared through the Chicago Mercantile Exchange ("CME") with the rest being subject to bilateral agreements between the Company and the swap counterparty. The Company's CME cleared swaps require that the Company post initial margin as determined by the CME, and in addition, variation margin is exchanged, typically in cash, for changes in the fair value of the CME cleared swaps. Beginning in January 2017, as a result of a change in the CME's rulebook, the exchange of variation margin for CME cleared swaps is legally considered to be the settlement of the derivative itself as opposed to a pledge of collateral. Accordingly, beginning in 2017, the Company accounts for the daily exchange of variation margin associated with its CME cleared interest rate swaps as a direct increase or decrease to the carrying value of the related derivative asset or liability. The carrying value of CME cleared interest rate swaps on the Company's consolidated balance sheets is the unsettled fair value of those instruments. A TBA security is a forward contract for the purchase or sale of a generic Agency MBS at a predetermined price 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. The Company executes TBA dollar roll transactions which effectively delay the settlement of a forward purchase of a TBA Agency RMBS by entering into an offsetting short position (referred to as a "pair off"), net settling the paired-off positions in cash, and simultaneously entering a similar TBA contract for a later settlement date. TBA securities purchased for a forward settlement month are generally priced at a discount relative to TBA securities sold for settlement in the current month. This discount, often referred to as “drop income” is the economic equivalent of net interest income on the underlying Agency securities over the roll period (interest income less implied financing cost). The Company accounts for TBA securities as derivative instruments because the Company cannot assert that it is probable at inception and throughout the term of an individual TBA contract that its settlement will result in physical delivery of the underlying Agency RMBS, or the individual TBA contract will not settle in the shortest time period possible. Please refer to Note 4 for additional information regarding the Company's derivative instruments as well as Note 5 for information on how the fair value of these instruments are calculated.
Stock-based Compensation [Policy Text Block]	Share-Based Compensation Pursuant to the Company’s 2009 Stock and Incentive Plan, the Company may grant share-based compensation to eligible employees, directors or consultants or advisers to the Company, including stock awards, stock options, stock appreciation rights, dividend equivalent rights, performance shares, and restricted stock units. The Company's restricted stock currently issued and outstanding under this plan may be settled only in shares of its common stock, and therefore are treated as equity awards with their fair value measured at the grant date and recognized as compensation cost over the requisite service period with a corresponding credit to shareholders' equity. The requisite service period is the period during which an employee is required to provide service in exchange for an award, which is equivalent to the vesting period specified in the terms of the time-based restricted stock award. None of the Company's restricted stock awards have performance based conditions. The Company does not currently have any share-based compensation issued or outstanding other than restricted stock issued to its employees, officers, and directors.
Contingencies [Policy Text Block]	Contingencies In the normal course of business, there may be various lawsuits, claims, and other contingencies pending against the Company. On a quarterly basis, the Company evaluates whether to establish provisions for estimated losses from those matters. The Company recognizes a liability for a contingent loss when: (a) the underlying causal event has occurred prior to the balance sheet date; (b) it is probable that a loss has been incurred; and (c) there is a reasonable basis for estimating that loss. A liability is not recognized for a contingent loss when it is only possible or remotely possible that a loss has been incurred, however, possible contingent losses shall be disclosed. If the contingent loss (or an additional loss in excess of any accrual) is at least a reasonable possibility and material, then the Company discloses a reasonable estimate of the possible loss or range of loss, if such reasonable estimate can be made. If the Company cannot make a reasonable estimate of the possible material loss, or range of loss, then that fact is disclosed.
Recent Accounting Pronouncements [Text Block]	Recent Accounting Pronouncements The Financial Accounting Standards Board ("FASB") issued ASU No. 2017-08, Receivables-Nonrefundable Fees and Other Costs, which shortens the amortization period for certain callable debt securities held at a premium, requiring the premium to be amortized to the earliest call date. The amendments in this ASU are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018 and early adoption is permitted. The amendments in this Update should be applied using the modified-retrospective transition approach and will require disclosures for the change in accounting principle. The Company does not expect this ASU to have a material impact on the Company's consolidated financial statements. FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which contains significant amendments to hedge accounting with the main objective of better aligning an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. To meet that objective, the amendments expand and refine hedge accounting for both non-financial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. This ASU also includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness as well as changes to current disclosure requirements. The amendments in this ASU are effective for public business entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, and early adoption is permitted. All transition requirements and elections will be applied to hedging relationships existing on the date of adoption. The effect of adoption will be reflected as of the beginning of the fiscal year of adoption, and the amended presentation and disclosure guidance is required only prospectively. The Company does not currently apply hedge accounting, but is evaluating the impact this ASU would have on its consolidated financial statements if the Company elects to adopt hedge accounting in the future.

Mortgage Backed Securities (Tab

Mortgage Backed Securities (Tables)	9 Months Ended
	Sep. 30, 2017
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	The following tables present the Company’s MBS by investment type as of the dates indicated: September 30, 2017 Par Net Premium (Discount) Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value WAC (1) CMBS: Agency $ 1,302,237 $ 12,688 1,314,925 $ 6,187 $ (13,623 ) 1,307,489 2.99 % Non-Agency 40,780 (4,452 ) 36,328 2,877 — 39,205 5.48 % 1,343,017 8,236 1,351,253 9,064 (13,623 ) 1,346,694 CMBS IO (2) : Agency — 394,380 394,380 7,592 (164 ) 401,808 0.63 % Non-Agency — 322,735 322,735 6,254 (330 ) 328,659 0.61 % — 717,115 717,115 13,846 (494 ) 730,467 RMBS: Agency fixed-rate 522,099 19,163 541,262 — (1,903 ) 539,359 3.52 % Agency adjustable-rate 294,254 11,011 305,265 1,263 (2,746 ) 303,782 3.05 % Non-Agency 1,113 — 1,113 49 (20 ) 1,142 6.75 % 817,466 30,174 847,640 1,312 (4,669 ) 844,283 Total AFS securities: $ 2,160,483 $ 755,525 $ 2,916,008 $ 24,222 $ (18,786 ) $ 2,921,444 (1) The weighted average coupon ("WAC") is the gross interest rate of the security weighted by the outstanding principal balance (or by notional balance in the case of an IO security). (2) The notional balance for Agency CMBS IO and non-Agency CMBS IO was $14,253,392 and $11,061,377 , respectively, as of September 30, 2017 . December 31, 2016 Par Net Premium (Discount) Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value WAC (1) CMBS: Agency $ 1,152,586 $ 13,868 $ 1,166,454 $ 6,209 $ (28,108 ) $ 1,144,555 3.12 % Non-Agency 79,467 (6,718 ) 72,749 5,467 — 78,216 4.72 % 1,232,053 7,150 1,239,203 11,676 (28,108 ) 1,222,771 CMBS IO (2) : Agency — 411,737 411,737 3,523 (3,362 ) 411,898 0.67 % Non-Agency — 346,155 346,155 1,548 (5,055 ) 342,648 0.61 % — 757,892 757,892 5,071 (8,417 ) 754,546 RMBS: Agency adjustable-rate $ 1,157,258 $ 57,066 $ 1,214,324 $ 2,832 $ (15,951 ) $ 1,201,205 3.05 % Non-Agency 33,572 (24 ) 33,548 64 (50 ) 33,562 3.58 % 1,190,830 57,042 1,247,872 2,896 (16,001 ) 1,234,767 Total AFS securities: $ 2,422,883 $ 822,084 $ 3,244,967 $ 19,643 $ (52,526 ) $ 3,212,084 (1) The WAC is the gross interest rate of the pool of mortgages underlying the security weighted by the outstanding principal balance (or by notional balance in the case of an IO security). (2) The notional balance for the Agency CMBS IO and non-Agency CMBS IO was $13,106,912 and $10,884,964 , respectively, as of December 31, 2016 .
Schedule of Realized Gain (Loss)	The following table presents information regarding the sales included in "loss on sale of investments, net" on the Company's consolidated statements of comprehensive income for the periods indicated: Three Months Ended September 30, 2017 2016 Proceeds Received Realized Gain (Loss) Proceeds Received Realized Gain (Loss) Agency RMBS $ 393,502 $ (5,160 ) $ — $ — Agency CMBS 13,433 (51 ) — — $ 406,935 $ (5,211 ) $ — $ — Nine Months Ended September 30, 2017 2016 Proceeds Received Realized Gain (Loss) Proceeds Received Realized Gain (Loss) Agency RMBS $ 716,560 $ (12,392 ) $ 54,178 $ (3,010 ) Agency CMBS 206,993 523 — — Non-Agency CMBS 35,705 1,199 33,640 (1,228 ) Non-Agency RMBS 16,407 42 — — $ 975,665 $ (10,628 ) $ 87,818 $ (4,238 )
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	The following table presents certain information for those MBS in an unrealized loss position as of the dates indicated: September 30, 2017 December 31, 2016 Fair Value Gross Unrealized Losses # of Securities Fair Value Gross Unrealized Losses # of Securities Continuous unrealized loss position for less than 12 months: Agency MBS $ 1,377,438 $ (13,201 ) 76 $ 1,738,094 $ (38,469 ) 133 Non-Agency MBS 38,979 (151 ) 6 205,484 (2,773 ) 48 Continuous unrealized loss position for 12 months or longer: Agency MBS $ 206,045 $ (5,236 ) 17 $ 427,405 $ (8,952 ) 72 Non-Agency MBS 15,749 (199 ) 11 81,660 (2,332 ) 26

Repurchase Agreements (Tables)

Repurchase Agreements (Tables)	9 Months Ended
	Sep. 30, 2017
Disclosure of Repurchase Agreements [Abstract]
Schedule of Underlying Assets of Repurchase Agreements when Amount of Repurchase Agreements Exceeds 10 Percent of Assets [Table Text Block]	The Company’s repurchase agreements outstanding as of September 30, 2017 and December 31, 2016 are summarized in the following tables: September 30, 2017 December 31, 2016 Collateral Type Balance Weighted Average Rate Fair Value of Collateral Pledged Balance Weighted Average Rate Fair Value of Collateral Pledged Agency CMBS $ 1,188,230 1.31 % $ 1,250,575 $ 1,005,726 0.82 % $ 1,095,002 Non-Agency CMBS 15,625 2.14 % 18,365 66,881 1.63 % 77,840 Agency CMBS IO 336,187 2.06 % 389,637 346,892 1.57 % 407,481 Non-Agency CMBS IO 279,981 2.15 % 327,976 291,199 1.67 % 341,139 Agency RMBS 695,841 1.31 % 727,727 1,157,302 0.82 % 1,191,147 Non-Agency RMBS — — % — 26,149 1.98 % 31,952 Securitization financing bond 3,366 2.58 % 3,723 4,803 2.00 % 5,278 Total repurchase agreements $ 2,519,230 1.51 % $ 2,718,003 $ 2,898,952 1.03 % $ 3,149,839
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Table Text Block]	The following table provides information on the remaining term to maturity and original term to maturity for the Company's repurchase agreements as of the periods indicated: September 30, 2017 December 31, 2016 Remaining Term to Maturity Balance WAVG Original Term to Maturity Balance WAVG Original Term to Maturity Less than 30 days $ 1,725,518 36 $ 2,480,213 58 30 to 90 days 793,712 89 418,739 87 Total $ 2,519,230 53 $ 2,898,952 63
Schedule of Repurchase Agreement Counterparties with Whom Repurchase Agreements Exceed 10 Percent of Stockholders' Equity [Table Text Block]	The following table lists the counterparties with whom the Company had over 10% of its shareholders' equity at risk (defined as the excess of collateral pledged over the borrowings outstanding): September 30, 2017 Counterparty Name Balance Weighted Average Rate Equity at Risk Wells Fargo Bank, N. A. and affiliates $ 349,965 2.10 % $ 57,992

Derivatives (Tables)

Derivatives (Tables)	9 Months Ended
	Sep. 30, 2017
Derivative [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The table below summarizes information about the fair value by type of derivative instrument on the Company's consolidated balance sheets as of the dates indicated: September 30, 2017 December 31, 2016 Type of Derivative Instruments Balance Sheet Location Fair Value Fair Value (1) Interest rate swaps Derivative assets $ 368 $ 28,534 TBA securities Derivative assets — — $ 368 $ 28,534 Interest rate swaps Derivative liabilities $ — $ (6,922 ) TBA securities Derivative liabilities (133 ) — $ (133 ) $ (6,922 ) (1) Refer to Note 1 regarding information on a change in the CME rulebook. Amounts reported on the consolidated balance sheet as of September 30, 2017 for its interest rate swaps reflect the netting of the derivative asset or liability with the related collateral received or posted, respectively. The net amounts comparable to September 30, 2017 for the derivative asset and derivative liabilities as of December 31, 2016 were $104 and $(576) , respectively.
Schedule of Notional Amounts of Outstanding Derivative Positions	The tables below summarize changes in our derivative instruments for the periods indicated: Type of Derivative Instrument Notional Amount as of December 31, 2016 Additions Settlements, Terminations, or Pair-Offs Notional Amount as of September 30, 2017 Receive-fixed interest rate swaps $ 425,000 $ — $ (325,000 ) $ 100,000 Pay-fixed interest rate swaps 3,455,000 3,010,000 (920,000 ) 5,545,000 TBA securities — 3,814,000 (3,164,000 ) 650,000
Derivative Instruments, Gain (Loss)	The table below provides detail of the Company's "gain (loss) on derivative instruments, net" by type of derivative for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, Type of Derivative Instrument 2017 2016 2017 2016 Receive-fixed interest rate swaps $ (99 ) $ (2,976 ) $ 746 $ 11,301 Pay-fixed interest rate swaps (611 ) 2,555 (18,799 ) (59,912 ) TBA securities 6,703 — 8,419 — Eurodollar futures — 2,830 — (13,542 ) Gain (loss) on derivative instruments, net $ 5,993 $ 2,409 $ (9,634 ) $ (62,153 )
Offsetting Assets	Offsetting of Assets Gross Amount of Recognized Assets Gross Amount Offset in the Balance Sheet Net Amount of Assets Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (1) Net Amount Financial Instruments Received as Collateral Cash Received as Collateral September 30, 2017 Interest rate swaps $ 368 $ — $ 368 $ — $ — $ 368 TBA securities — — — — — — Derivative assets $ 368 $ — $ 368 $ — $ — $ 368 December 31, 2016: Interest rate swaps $ 28,534 $ — $ 28,534 $ (6,449 ) $ (22,085 ) $ — TBA securities — — — — — — Derivative assets $ 28,534 $ — $ 28,534 $ (6,449 ) $ (22,085 ) $ —
Offsetting Liabilities	Offsetting of Liabilities Gross Amount of Recognized Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (1) Net Amount Financial Instruments Posted as Collateral Cash Posted as Collateral September 30, 2017 Interest rate swaps $ — $ — $ — $ — $ — $ — TBA securities 133 — 133 — (63 ) 70 Derivative liabilities $ 133 $ — $ 133 $ — $ (63 ) $ 70 December 31, 2016: Interest rate swaps $ 6,922 $ — $ 6,922 $ (6,913 ) $ — $ 9 TBA securities — — — — — — Derivative liabilities $ 6,922 $ — $ 6,922 $ (6,913 ) $ — $ 9 (1) Amounts disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented.
Interest Rate Swap
Derivative [Line Items]
Schedule of Derivative Instruments	The following tables present information about the Company's interest rate swaps as of the dates indicated: September 30, 2017 Weighted-Average: Years to Maturity: Net Notional Amount (1) Pay Rate (2) Life Remaining (in Years) Fair Value < 3 years $ 3,110,000 1.39 % 0.9 $ 368 >3 and < 6 years 1,160,000 1.66 % 4.2 — >6 and < 10 years 1,175,000 2.45 % 8.1 — Total $ 5,445,000 1.68 % 3.2 $ 368 December 31, 2016 Weighted-Average: Years to Maturity: Net Notional Amount (1) Pay Rate (2) Life Remaining (in Years) Fair Value < 3 years $ 595,000 0.73 % 2.3 $ 4,348 >3 and < 6 years 1,185,000 1.47 % 4.3 8,631 >6 and < 10 years 1,250,000 2.42 % 8.9 8,633 Total $ 3,030,000 1.58 % 5.3 $ 21,612 (1) The net notional amounts included in the tables above represent pay-fixed interest rate swaps, net of receive-fixed interest rate swaps and include $2,425,000 and $2,725,000 of pay-fixed forward starting interest rate swaps as of September 30, 2017 and December 31, 2016 , respectively. (2) Excluding forward starting pay-fixed interest rate swaps, the weighted average pay rate was 1.34% and 0.73% as of September 30, 2017 and December 31, 2016, respectively.
TBA security
Derivative [Line Items]
Schedule of Derivative Instruments	The following table summarizes information about the Company's TBA securities as of September 30, 2017 : September 30, 2017 Notional Amount (1) Cost Basis (2) Market Value (3) Net Carrying Value (4) 30-year 4.0% TBA securities $ 650,000 $ 683,813 $ 683,680 $ (133 ) (1) Notional amount represents the par value (or principal balance) of the underlying Agency MBS. (2) Cost basis represents the forward price to be paid for the underlying Agency MBS as if settled. (3) Market value is the current fair value of the TBA contract and represents the estimated fair value of the underlying Agency security as of the end of the period. (4) Net carrying value represents the difference between the market value and the cost basis of the TBA contract as of the end of the period and is included on the consolidated balance sheets within "derivative assets (liabilities)".

Fair Value of Financial Instr18

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table presents the fair value of the Company’s financial instruments segregated by the hierarchy level of the fair value estimate that are measured at fair value on a recurring basis as of the dates indicated: September 30, 2017 Fair Value Level 1 - Unadjusted Quoted Prices in Active Markets Level 2 - Observable Inputs Level 3 - Unobservable Inputs Assets: Mortgage-backed securities $ 2,921,444 $ — $ 2,913,877 $ 7,567 Interest rate swaps 368 — 368 — Total assets carried at fair value $ 2,921,812 $ — $ 2,914,245 $ 7,567 Liabilities: TBA securities 133 — 133 — Total liabilities carried at fair value $ 133 $ — $ 133 $ — December 31, 2016 Fair Value Level 1 - Unadjusted Quoted Prices in Active Markets Level 2 - Observable Inputs Level 3 - Unobservable Inputs Assets: Mortgage-backed securities $ 3,212,084 $ — $ 3,201,157 $ 10,927 Interest rate swaps 28,534 — 28,534 — Total assets carried at fair value $ 3,240,618 $ — $ 3,229,691 $ 10,927 Liabilities: Interest rate swaps $ 6,922 $ — $ 6,922 $ — Total liabilities carried at fair value $ 6,922 $ — $ 6,922 $ —
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The activity of the instruments measured at fair value on a recurring basis using Level 3 inputs is presented in the following table for the period indicated: Level 3 Fair Value Non-Agency CMBS Non-Agency RMBS Total Balance as of December 31, 2016 $ 9,669 $ 1,258 $ 10,927 Unrealized loss included in OCI (1) (1,422 ) 16 (1,406 ) Principal payments (3,896 ) (133 ) (4,029 ) Accretion 2,075 — 2,075 Balance as of September 30, 2017 $ 6,426 $ 1,141 $ 7,567 (1) Amount included in "unrealized gain on available-for-sale investments, net" on consolidated statements of comprehensive income (loss).
Fair Value, by Balance Sheet Grouping	The following table presents a summary of the carrying value and estimated fair values of the Company’s financial instruments as of the dates indicated: September 30, 2017 December 31, 2016 Carrying Value Fair Value Carrying Value Fair Value Assets: Mortgage-backed securities $ 2,921,444 $ 2,921,444 $ 3,212,084 $ 3,212,084 Mortgage loans held for investment, net (1) 16,523 13,674 19,036 15,971 Derivative assets 368 368 28,534 28,534 Liabilities: Repurchase agreements (2) $ 2,519,230 $ 2,519,230 $ 2,898,952 $ 2,898,952 Non-recourse collateralized financing (1) 5,706 5,722 6,440 6,357 Derivative liabilities 133 133 6,922 6,922 (1) The Company determines the fair value of its mortgage loans held for investment, net and its non-recourse collateralized financing using internally developed cash flow models with inputs similar to those used to estimate the fair value of the Company's Level 3 non-Agency MBS. (2) The carrying value of repurchase agreements generally approximates fair value due to their short term maturities.

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	The following table presents a rollforward of the restricted stock activity for the periods indicated: Three Months Ended September 30, 2017 2016 Shares Weighted Average Grant Date Fair Value Per Share Shares Weighted Average Grant Date Fair Value Per Share Restricted stock outstanding as of beginning of period 353,103 $ 7.01 561,089 $ 7.54 Restricted stock granted — — — — Restricted stock vested — — — — Restricted stock outstanding as of end of period 353,103 $ 7.01 561,089 $ 7.54 Nine Months Ended September 30, 2017 2016 Shares Weighted Average Grant Date Fair Value Per Share Shares Weighted Average Grant Date Fair Value Per Share Restricted stock outstanding as of beginning of period 553,396 $ 7.55 696,597 $ 8.54 Restricted stock granted 138,166 6.76 214,878 6.28 Restricted stock vested (338,459 ) 7.80 (350,386 ) 8.76 Restricted stock outstanding as of end of period 353,103 $ 7.01 561,089 $ 7.54

Organization and Summary of S20

Organization and Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Cash and cash equivalents	$ 117,702	$ 74,120
Restricted cash	43,987	24,769
Total cash, cash equivalents, and restricted cash shown on consolidated statement of cash flows	$ 161,689	$ 98,889	$ 158,091	$ 85,125

Mortgage Backed Securities (Det

Mortgage Backed Securities (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2017		Sep. 30, 2016	Sep. 30, 2017		Sep. 30, 2016	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		$ 2,160,483			$ 2,160,483			$ 2,422,883
Available-for-sale MBS, Net Premium (Discount)		755,525			755,525			822,084
Available-for-sale MBS, Amortized Cost		2,916,008			2,916,008			3,244,967
Available-for-sale MBS, Gross Unrealized Gain		24,222			24,222			19,643
Available-for-sale MBS, Gross Unrealized Loss		(18,786)			(18,786)			(52,526)
Available-for-sale MBS, Fair Value		2,921,444			2,921,444			3,212,084
Available-for-sale MBS, Sale Proceeds		406,935		$ 0	975,665		$ 87,818
Available-for-sale MBS, Gross Realized Gain (Loss)		5,211		0	(10,628)		(4,238)
Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Continuous Unrealized Loss Position for less than 12 months, Fair Value		1,377,438			1,377,438			1,738,094
Available-for-sale MBS, Continuous Unrealized Loss Position for less than 12 months, Accumulated Loss		$ (13,201)			$ (13,201)			$ (38,469)
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for less than 12 months		76			76			133
Available-for-sale MBS, Continuous Unrealized Loss Position for 12 months or longer, Fair Value		$ 206,045			$ 206,045			$ 427,405
Available-for-sale MBS, Continuous Unrealized Loss Position for 12 months or longer, Accumulated Loss		$ (5,236)			$ (5,236)			$ (8,952)
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for 12 months or longer		17			17			72
Non-Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Continuous Unrealized Loss Position for less than 12 months, Fair Value		$ 38,979			$ 38,979			$ 205,484
Available-for-sale MBS, Continuous Unrealized Loss Position for less than 12 months, Accumulated Loss		$ (151)			$ (151)			$ (2,773)
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for less than 12 months		6			6			48
Available-for-sale MBS, Continuous Unrealized Loss Position for 12 months or longer, Fair Value		$ 15,749			$ 15,749			$ 81,660
Available-for-sale MBS, Continuous Unrealized Loss Position for 12 months or longer, Accumulated Loss		$ (199)			$ (199)			$ (2,332)
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for 12 months or longer		11			11			26
CMBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		$ 1,343,017			$ 1,343,017			$ 1,232,053
Available-for-sale MBS, Net Premium (Discount)		8,236			8,236			7,150
Available-for-sale MBS, Amortized Cost		1,351,253			1,351,253			1,239,203
Available-for-sale MBS, Gross Unrealized Gain		9,064			9,064			11,676
Available-for-sale MBS, Gross Unrealized Loss		(13,623)			(13,623)			(28,108)
Available-for-sale MBS, Fair Value		1,346,694			1,346,694			1,222,771
CMBS | Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		1,302,237			1,302,237			1,152,586
Available-for-sale MBS, Net Premium (Discount)		12,688			12,688			13,868
Available-for-sale MBS, Amortized Cost		1,314,925			1,314,925			1,166,454
Available-for-sale MBS, Gross Unrealized Gain		6,187			6,187			6,209
Available-for-sale MBS, Gross Unrealized Loss		(13,623)			(13,623)			(28,108)
Available-for-sale MBS, Fair Value		$ 1,307,489			$ 1,307,489			$ 1,144,555
Available-for-sale MBS, Weighted Average Coupon	[1]	2.99%			2.99%			3.12%
Available-for-sale MBS, Sale Proceeds		$ 13,433		0	$ 206,993		0
Available-for-sale MBS, Gross Realized Losses				0	(51)		0
Available-for-sale Securities MBS, Gross Realized Gains					523
CMBS | Non-Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		40,780			40,780			$ 79,467
Available-for-sale MBS, Net Premium (Discount)		(4,452)			(4,452)			(6,718)
Available-for-sale MBS, Amortized Cost		36,328			36,328			72,749
Available-for-sale MBS, Gross Unrealized Gain		2,877			2,877			5,467
Available-for-sale MBS, Gross Unrealized Loss		0			0			0
Available-for-sale MBS, Fair Value		$ 39,205			$ 39,205			$ 78,216
Available-for-sale MBS, Weighted Average Coupon	[1]	5.48%			5.48%			4.72%
Available-for-sale MBS, Sale Proceeds					$ 35,705		33,640
Available-for-sale MBS, Gross Realized Losses							(1,228)
Available-for-sale Securities MBS, Gross Realized Gains					1,199
CMBS IO
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		$ 0			0			$ 0
Available-for-sale MBS, Net Premium (Discount)		717,115			717,115			757,892
Available-for-sale MBS, Amortized Cost		717,115			717,115			757,892
Available-for-sale MBS, Gross Unrealized Gain		13,846			13,846			5,071
Available-for-sale MBS, Gross Unrealized Loss		(494)			(494)			(8,417)
Available-for-sale MBS, Fair Value		730,467			730,467			754,546
CMBS IO | Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		0	[2]		0	[2]		0	[3]
Available-for-sale MBS, Net Premium (Discount)		394,380			394,380			411,737
Available-for-sale MBS, Amortized Cost		394,380			394,380			411,737
Available-for-sale MBS, Gross Unrealized Gain		7,592			7,592			3,523
Available-for-sale MBS, Gross Unrealized Loss		(164)			(164)			(3,362)
Available-for-sale MBS, Fair Value		$ 401,808			$ 401,808			$ 411,898
Available-for-sale MBS, Weighted Average Coupon	[1]	0.63%			0.63%			0.67%
Notional balance for interest only securities		$ 14,253,392			$ 14,253,392			$ 13,106,912
CMBS IO | Non-Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	[2]	0			0
Available-for-sale MBS, Net Premium (Discount)		322,735			322,735			346,155
Available-for-sale MBS, Amortized Cost		322,735			322,735			346,155
Available-for-sale MBS, Gross Unrealized Gain		6,254			6,254			1,548
Available-for-sale MBS, Gross Unrealized Loss		(330)			(330)			(5,055)
Available-for-sale MBS, Fair Value		$ 328,659			$ 328,659			$ 342,648
Available-for-sale MBS, Weighted Average Coupon	[1]	0.61%			0.61%			0.61%
Notional balance for interest only securities		$ 11,061,377			$ 11,061,377			$ 10,884,964
RMBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		817,466			817,466			1,190,830
Available-for-sale MBS, Net Premium (Discount)		30,174			30,174			57,042
Available-for-sale MBS, Amortized Cost		847,640			847,640			1,247,872
Available-for-sale MBS, Gross Unrealized Gain		1,312			1,312			2,896
Available-for-sale MBS, Gross Unrealized Loss		(4,669)			(4,669)			(16,001)
Available-for-sale MBS, Fair Value		844,283			844,283			1,234,767
RMBS | Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Sale Proceeds		393,502		0	716,560		54,178
Available-for-sale MBS, Gross Realized Losses		(5,160)		$ 0	(12,392)		(3,010)
RMBS | Agency MBS | Agency fixed-rate
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		522,099			522,099
Available-for-sale MBS, Net Premium (Discount)		19,163			19,163
Available-for-sale MBS, Amortized Cost		541,262			541,262
Available-for-sale MBS, Gross Unrealized Gain		0			0
Available-for-sale MBS, Gross Unrealized Loss		(1,903)			(1,903)
Available-for-sale MBS, Fair Value		$ 539,359			$ 539,359
Available-for-sale MBS, Weighted Average Coupon	[1]	3.52%			3.52%
RMBS | Agency MBS | Agency adjustable-rate
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		$ 294,254			$ 294,254
Available-for-sale MBS, Net Premium (Discount)		11,011			11,011
Available-for-sale MBS, Amortized Cost		305,265			305,265
Available-for-sale MBS, Gross Unrealized Gain		1,263			1,263
Available-for-sale MBS, Gross Unrealized Loss		(2,746)			(2,746)
Available-for-sale MBS, Fair Value		$ 303,782			$ 303,782
Available-for-sale MBS, Weighted Average Coupon	[1]	3.05%			3.05%
RMBS | Non-Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance		$ 1,113			$ 1,113			33,572
Available-for-sale MBS, Net Premium (Discount)		0			0			(24)
Available-for-sale MBS, Amortized Cost		1,113			1,113			33,548
Available-for-sale MBS, Gross Unrealized Gain		49			49			64
Available-for-sale MBS, Gross Unrealized Loss		(20)			(20)			(50)
Available-for-sale MBS, Fair Value		$ 1,142			$ 1,142			$ 33,562
Available-for-sale MBS, Weighted Average Coupon	[1]	6.75%			6.75%			3.58%
Available-for-sale MBS, Sale Proceeds					$ 16,407		0
Available-for-sale MBS, Gross Realized Losses							$ 0
Available-for-sale Securities MBS, Gross Realized Gains					$ 42
Variable interest rate [Member] | RMBS | Agency MBS
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance								$ 1,157,258
Available-for-sale MBS, Net Premium (Discount)								57,066
Available-for-sale MBS, Amortized Cost								1,214,324
Available-for-sale MBS, Gross Unrealized Gain								2,832
Available-for-sale MBS, Gross Unrealized Loss								(15,951)
Available-for-sale MBS, Fair Value								$ 1,201,205
Available-for-sale MBS, Weighted Average Coupon	[1]							3.05%
[1]	The weighted average coupon ("WAC") is the gross interest rate of the security weighted by the outstanding principal balance (or by notional balance in the case of an IO security).
[2]	The notional balance for Agency CMBS IO and non-Agency CMBS IO was $14,253,392 and $11,061,377, respectively, as of September 30, 2017.
[3]	The notional balance for the Agency CMBS IO and non-Agency CMBS IO was $13,106,912 and $10,884,964, respectively, as of December 31, 2016.

Repurchase Agreements (Details)

Repurchase Agreements (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 2,519,230	$ 2,898,952
Weighted Average Rate	1.51%	1.03%
Fair Value of Collateral Pledged	$ 2,718,003	$ 3,149,839
Securitization financing bond
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 3,366	$ 4,803
Weighted Average Rate	2.58%	2.00%
Fair Value of Collateral Pledged	$ 3,723	$ 5,278
CMBS | Agency MBS
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 1,188,230	$ 1,005,726
Weighted Average Rate	1.31%	0.82%
Fair Value of Collateral Pledged	$ 1,250,575	$ 1,095,002
CMBS | Non-Agency MBS
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 15,625	$ 66,881
Weighted Average Rate	2.14%	1.63%
Fair Value of Collateral Pledged	$ 18,365	$ 77,840
CMBS IO | Agency MBS
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 336,187	$ 346,892
Weighted Average Rate	2.06%	1.57%
Fair Value of Collateral Pledged	$ 389,637	$ 407,481
CMBS IO | Non-Agency MBS
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 279,981	$ 291,199
Weighted Average Rate	2.15%	1.67%
Fair Value of Collateral Pledged	$ 327,976	$ 341,139
RMBS | Agency MBS
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 695,841	$ 1,157,302
Weighted Average Rate	1.31%	0.82%
Fair Value of Collateral Pledged	$ 727,727	$ 1,191,147
RMBS | Non-Agency MBS
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 0	$ 26,149
Weighted Average Rate	0.00%	1.98%
Fair Value of Collateral Pledged	$ 0	$ 31,952

Repurchase Agreements Remaining

Repurchase Agreements Remaining Term to Maturity (Details) $ in Thousands	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 2,519,230	$ 2,898,952
WAVG Original Term to Maturity	53	63
Less than 30 days
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 1,725,518	$ 2,480,213
WAVG Original Term to Maturity	36	58
30 to 90 days
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Balance	$ 793,712	$ 418,739
WAVG Original Term to Maturity	89	87

Repurchase Agreements Counterpa

Repurchase Agreements Counterparty Information (Details) $ in Thousands	Sep. 30, 2017USD ($)Agreements
Repurchase Agreement Counterparty [Line Items]
Borrowings outstanding with counterparty	$ 349,965
Weighted Average Rate	2.10%
Equity at Risk	$ 57,992
Line of Credit Facility, Amount Outstanding	343,780
Line of Credit Facility, Maximum Borrowing Capacity	$ 400,000
Line of Credit Facility, Interest Rate at Period End	2.10%
Number of Counterparties with Borrowings Outstanding | Agreements	18
Available Repurchase Agreement Counterparties | Agreements	34

Repurchase Agreements Offsettin

Repurchase Agreements Offsetting (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Offsetting Liabilities [Line Items]
Gross Amount of Recognized Liabilities		$ 2,519,230	$ 2,898,952
Gross Amount Offset in the Balance Sheet		0	0
Net Amount of Liabilities Presented in the Balance Sheet		2,519,230	2,898,952
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Securities	[1]	(2,519,230)	(2,898,952)
Securities Sold under Agreements to Repurchase, Collateral, Right to Reclaim Cash		0	0
Securities Sold under Agreements to Repurchase, Amount Offset Against Collateral		$ 0	$ 0
[1]	Amounts disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented.

Interest Rate Swap (Details)

Interest Rate Swap (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Derivative [Line Items]
Derivative assets, fair value		$ 368		$ 368		$ 28,534	[1]
Derivative liabilities, fair value		(133)		(133)		(6,922)	[1]
Derivative asset, net of variation margin						104
Derivative liability, net of variation margin						$ (576)
Loss on derivative instruments, net		$ (5,993)	$ (2,409)	$ 9,634	$ 62,153
Derivative, Average Fixed Interest Rate, Current Effective		1.34%		1.34%		0.73%
Other Footnotes Disclosing Derivative-Related Information, Cross-Reference				Please refer to Note 1 for information related to the Company's accounting policy for its derivative instruments.
Forward starting interest rate swap
Derivative [Line Items]
Derivative, Notional Amount		$ 2,425,000		$ 2,425,000		$ 2,725,000
TBA security
Derivative [Line Items]
Derivative, Notional Amount		650,000		650,000		0
Derivative Instruments Not Designated as Hedging Instruments, Gain		6,703	0	8,419	0
Eurodollar Future
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain			2,830
Derivative Instruments Not Designated as Hedging Instruments, Loss		0		0	(13,542)
Receive-fixed interest rate swap | Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount		100,000		100,000		425,000
Derivative Instruments Not Designated as Hedging Instruments, Gain				746	11,301
Derivative Instruments Not Designated as Hedging Instruments, Loss		(99)	(2,976)
Pay-fixed interest rate swap | Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount		5,545,000		5,545,000		3,455,000
Derivative Instruments Not Designated as Hedging Instruments, Gain			$ 2,555
Derivative Instruments Not Designated as Hedging Instruments, Loss		(611)		(18,799)	$ (59,912)
Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Swap
Derivative [Line Items]
Derivative assets, fair value		368		368		28,534	[1]
Derivative liabilities, fair value		0		0		(6,922)	[1]
Derivative, Notional Amount	[2]	$ 5,445,000		$ 5,445,000		$ 3,030,000
Derivative, Average Fixed Interest Rate	[3]	1.68%		1.68%		1.58%
Derivative, Average Remaining Maturity				3 years 2 months 12 days		5 years 3 months 18 days
Derivative, Fair Value, Net		$ 368		$ 368		$ 21,612
Not Designated as Hedging Instrument, Trading [Member] | TBA security
Derivative [Line Items]
Derivative liabilities, fair value		(133)		(133)		0
Maturity in three years or less | Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount	[2]	$ 3,110,000		$ 3,110,000		$ 595,000
Derivative, Average Fixed Interest Rate		1.39%		1.39%		0.73%
Derivative, Average Remaining Maturity				10 months 24 days		2 years 3 months 18 days
Derivative, Fair Value, Net		$ 368		$ 368		$ 4,348
Maturity between 3 and 6 years | Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount	[2]	$ 1,160,000		$ 1,160,000		$ 1,185,000
Derivative, Average Fixed Interest Rate		1.66%		1.66%		1.47%
Derivative, Average Remaining Maturity				4 years 2 months 12 days		4 years 3 months 18 days
Derivative, Fair Value, Net		$ 0		$ 0		$ 8,631
Maturity between 6 and 10 years | Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount	[2]	$ 1,175,000		$ 1,175,000		$ 1,250,000
Derivative, Average Fixed Interest Rate		2.45%		2.45%		2.42%
Derivative, Average Remaining Maturity				8 years 1 month 6 days		8 years 10 months 24 days
Derivative, Fair Value, Net		$ 0		$ 0		$ 8,633
[1]	Refer to Note 1 regarding information on a change in the CME rulebook. Amounts reported on the consolidated balance sheet as of September 30, 2017 for its interest rate swaps reflect the netting of the derivative asset or liability with the related collateral received or posted, respectively. The net amounts comparable to September 30, 2017 for the derivative asset and derivative liabilities as of December 31, 2016 were $104 and $(576), respectively.
[2]	The net notional amounts included in the tables above represent pay-fixed interest rate swaps, net of receive-fixed interest rate swaps and include $2,425,000 and $2,725,000 of pay-fixed forward starting interest rate swaps as of September 30, 2017 and December 31, 2016, respectively.
[3]	Excluding forward starting pay-fixed interest rate swaps, the weighted average pay rate was 1.34% and 0.73% as of September 30, 2017 and December 31, 2016, respectively.

Derivatives TBA securities (Det

Derivatives TBA securities (Details) - TBA security - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative, Notional Amount		$ 650,000	$ 0
Not Designated as Hedging Instrument, Trading [Member] | TBA 4 percent coupon [Member]
Derivative [Line Items]
Derivative, Notional Amount	[1]	650,000
Cost Basis,TBA	[2]	683,813
Market value, TBA	[3]	683,680
Net carrying value, TBA	[4]	$ (133)
[1]	Notional amount represents the par value (or principal balance) of the underlying Agency MBS.
[2]	Cost basis represents the forward price to be paid for the underlying Agency MBS as if settled.
[3]	Market value is the current fair value of the TBA contract and represents the estimated fair value of the underlying Agency security as of the end of the period.
[4]	Net carrying value represents the difference between the market value and the cost basis of the TBA contract as of the end of the period and is included on the consolidated balance sheets within "derivative assets (liabilities)".

Derivatives Volume of Activity

Derivatives Volume of Activity (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
TBA security
Derivative [Line Items]
Beginning of Period Notional Amount	$ 0
Notional Amount of Derivative Instruments Added	3,814,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off	(3,164,000)
End of Period Notional Amount	650,000
Interest Rate Swap | Receive-fixed interest rate swap
Derivative [Line Items]
Beginning of Period Notional Amount	425,000
Notional Amount of Derivative Instruments Added	0
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off	(325,000)
End of Period Notional Amount	100,000
Interest Rate Swap | Pay-fixed interest rate swap
Derivative [Line Items]
Beginning of Period Notional Amount	3,455,000
Notional Amount of Derivative Instruments Added	3,010,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off	(920,000)
End of Period Notional Amount	$ 5,545,000

Derivatives Effect on Accumulat

Derivatives Effect on Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Derivative [Line Items]
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax		$ 450
Scenario, Forecast [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 210

Derivatives Offsetting Assets (

Derivatives Offsetting Assets (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Offsetting Assets [Line Items]
Derivative Asset, Fair Value, Gross Asset		$ 368	$ 28,534
Derivative Asset, Fair Value, Amount Not Offset Against Collateral		368	28,534
Derivative, Collateral, Obligation to Return Securities	[1]	0	(6,449)
Derivative, Collateral, Obligation to Return Cash		0	22,085	[1]
Derivative Asset, Fair Value, Amount Offset Against Collateral		368	0
Interest Rate Swap
Offsetting Assets [Line Items]
Derivative Asset, Fair Value, Gross Asset		368	28,534
Derivative Asset, Fair Value, Amount Not Offset Against Collateral		368	28,534
Derivative, Collateral, Obligation to Return Securities	[1]	0	(6,449)
Derivative, Collateral, Obligation to Return Cash		0	(22,085)
Derivative Asset, Fair Value, Amount Offset Against Collateral		$ 368	$ 0
[1]	Amounts disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented.

Derivatives Offsetting Liabilit

Derivatives Offsetting Liabilities (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Offsetting Liabilities [Line Items]
Derivative Liability, Fair Value, Gross Liability		$ 133	$ 6,922
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		133	6,922
Derivative, Collateral, Right to Reclaim Securities	[1]	0	(6,913)
Derivative, Collateral, Right to Reclaim Cash		(63)	0
Derivative Liability, Fair Value, Amount Offset Against Collateral		70	9
Interest Rate Swap
Offsetting Liabilities [Line Items]
Derivative Liability, Fair Value, Gross Liability		0	6,922
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		0	6,922
Derivative, Collateral, Right to Reclaim Securities	[1]	0	(6,913)
Derivative, Collateral, Right to Reclaim Cash		0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral		0	$ 9
TBA security
Offsetting Liabilities [Line Items]
Derivative Liability, Fair Value, Gross Liability		133
Derivative Liability, Fair Value, Amount Not Offset Against Collateral		133
Derivative, Collateral, Right to Reclaim Securities	[1]	0
Derivative, Collateral, Right to Reclaim Cash		(63)
Derivative Liability, Fair Value, Amount Offset Against Collateral		$ 70
[1]	Amounts disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented.

Fair Value of Financial Instr32

Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	$ 2,921,444	$ 3,212,084
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	368	28,534	[1]
Derivative asset	368	28,534
Total assets carried at fair value	2,921,812	3,240,618
Derivative liabilities	133	6,922
Total liabilities carried at fair value	133	6,922
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	0	0
Total assets carried at fair value	0	0
Total liabilities carried at fair value	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	2,913,877	3,201,157
Total assets carried at fair value	2,914,245	3,229,691
Total liabilities carried at fair value	133	6,922
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	7,567	10,927
Total assets carried at fair value	7,567	10,927
Total liabilities carried at fair value	0	0
TBA security
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	133
TBA security | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0
TBA security | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	133
TBA security | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0
Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset		28,534
Derivative liabilities		6,922
Interest Rate Swap | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0	0
Derivative liabilities		0
Interest Rate Swap | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	368	28,534
Derivative liabilities		6,922
Interest Rate Swap | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0	0
Derivative liabilities		0
Not Designated as Hedging Instrument, Economic Hedge [Member] | Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	$ 368	$ 28,534	[1]
[1]	Refer to Note 1 regarding information on a change in the CME rulebook. Amounts reported on the consolidated balance sheet as of September 30, 2017 for its interest rate swaps reflect the netting of the derivative asset or liability with the related collateral received or posted, respectively. The net amounts comparable to September 30, 2017 for the derivative asset and derivative liabilities as of December 31, 2016 were $104 and $(576), respectively.

Fair Value of Financial Instr33

Fair Value of Financial Instruments Level 3 (Details) - Fair Value, Measurements, Recurring $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	$ 10,927
Unrealized (loss) gain included in OCI	(1,406)	[1]
Principal payments	(4,029)
Accretion	2,075
Balance at the end of the period	7,567
Non-Agency CMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	9,669
Unrealized (loss) gain included in OCI	(1,422)	[1]
Principal payments	(3,896)
Accretion	2,075
Balance at the end of the period	6,426
Non-Agency RMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	1,258
Unrealized (loss) gain included in OCI	16	[1]
Principal payments	(133)
Accretion	0
Balance at the end of the period	$ 1,141
[1]	Amount included in "unrealized gain on available-for-sale investments, net" on consolidated statements of comprehensive income (loss).

Fair Value of Financial Instr34

Fair Value of Financial Instruments Recorded basis and Fair Value (Details) - USD ($) $ in Thousands		Sep. 30, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed securities		$ 2,921,444	$ 3,212,084
Derivative assets		368	28,534
Derivative liabilities		133	6,922
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed securities			3,212,084
Mortgage loans held for investment, net (1)		16,523	19,036
Derivative assets		368	28,534
Repurchase agreements (2)		2,519,230	2,898,952
Non-recourse collateralized financing (1)		5,706	6,440
Derivative liabilities		133	6,922
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed securities		2,921,444	3,212,084
Mortgage loans held for investment, net (1)	[1]	13,674	15,971
Derivative assets		368	28,534
Repurchase agreements (2)	[2]	2,519,230	2,898,952
Non-recourse collateralized financing (1)	[1]	5,722	6,357
Derivative liabilities		$ 133	$ 6,922
[1]	The Company determines the fair value of its mortgage loans held for investment, net and its non-recourse collateralized financing using internally developed cash flow models with inputs similar to those used to estimate the fair value of the Company's Level 3 non-Agency MBS.
[2]	The carrying value of repurchase agreements generally approximates fair value due to their short term maturities

Shareholders' Equity (Details)

Shareholders' Equity (Details) - $ / shares	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Preferred stock, shares authorized	50,000,000	50,000,000	50,000,000
Preferred stock, par value	$ 0.01	$ 0.01	$ 0.01
Preferred stock, shares issued	5,665,101	5,665,101	4,571,937
Preferred Stock, Liquidation Preference Per Share	$ 25	$ 25
Preferred Stock, Dividend Payment Terms		The Series A Preferred Stock pays a cumulative cash dividend equivalent to 8.50% of the $25.00 liquidation preference per share each year and the Series B Preferred Stock pays a cumulative cash dividend equivalent to 7.625% of the $25.00 liquidation preference per share each year.
Dividends declared per common share	$ 0.18
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	8,000,000	8,000,000
Preferred stock, shares issued	2,300,000	2,300,000	2,300,000
Preferred Stock, Dividend Rate, Percentage		8.50%
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized	7,000,000	7,000,000
Preferred stock, shares issued	3,365,101	3,365,101	2,271,937
Preferred Stock, Dividend Rate, Percentage		7.625%
Preferred Stock
Class of Stock [Line Items]
Dividends Payable, Date to be Paid	Oct. 16, 2017
Dividends Payable, Date of Record	Oct. 1, 2017
Common Stock
Class of Stock [Line Items]
Dividends Payable, Date to be Paid	Oct. 31, 2017
Dividends Payable, Date of Record	Oct. 3, 2017

Shareholders' Equity Share-base

Shareholders' Equity Share-based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based incentive plan, number of shares authorized for issuance	2,500,000		2,500,000
Share-based incentive plan, number of shares remaining for issuance	785,962		785,962
Stock-based compensation expense	$ 0	$ 1	$ 1,567	$ 2,066
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Rollforward]
Restricted stock outstanding as of beginning of period	353,103	561,089	553,396	696,597
Restricted stock granted	0	0	138,166	214,878
Restricted stock vested	0	0	(338,459)	(350,386)
Restricted stock outstanding as of end of period	353,103	561,089	353,103	561,089
Restricted stock as of beginning of period of period, nonvested, weighted average grant date fair value per share	$ 7.01	$ 7.54	$ 7.55	$ 8.54
Restricted stock granted, weighted average grant date fair value per share	0	0	6.76	6.28
Restricted stock vested, weighted average grant date fair value per share	0	0	7.80	8.76
Restricted stock as of end of period, nonvested, weighted average grant date fair value per share	$ 7.01	$ 7.54	$ 7.01	$ 7.54
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 1,505		$ 1,505
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			1 year 5 months 21 days

Subsequent Events Subsequent Ev

Subsequent Events Subsequent Events (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Nov. 03, 2017	Sep. 30, 2017
Subsequent Event [Line Items]
Subsequent stock issuance		$ 40,379
Common Stock
Subsequent Event [Line Items]
Subsequent stock issuance		$ 21
Stock Issued During Period, Shares, New Issues		2,048,288
Common Stock | Subsequent Event [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues	1,956,936
Common Stock Including Additional Paid in Capital [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Subsequent stock issuance	$ 14,078
Preferred Stock
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues		1,093,164
Preferred Stock | Subsequent Event [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, New Issues	89,313
Preferred Stock Including Additional Paid in Capital [Member]
Subsequent Event [Line Items]
Subsequent stock issuance		$ 25,884
Preferred Stock Including Additional Paid in Capital [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Subsequent stock issuance	$ 2,169