Dynex Capital (DX) 10-K 12 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 27, 2015	Jun. 30, 2014
Entity Information [Line Items]
Entity Registrant Name	DYNEX CAPITAL INC
Entity Central Index Key	826675
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		54,938,908
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$448,865,442

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
ASSETS
Mortgage-backed securities	$3,516,239	$4,018,161
Loans and Leases Receivable, Net Amount	39,700	55,423
Cash and cash equivalents	43,944	69,330
Restricted cash	42,263	13,385
Derivative assets	5,727	18,488
Principal receivable on investments	7,420	12,999
Accrued interest receivable	21,157	21,703
Investment in limited partnership	4,000	0
Other assets, net	7,861	7,648
Total assets	3,688,311	4,217,137
Liabilities:
Repurchase agreements	3,013,110	3,580,754
Payable for unsettled mortgage-backed securities	0	10,358
Non recourse collateralized financing	10,786	12,914
Derivative Liabilities	35,898	6,681
Accrued interest payable	1,947	2,548
Accrued dividends payable	15,622	16,601
Other liabilities	3,646	1,405
Total liabilities	3,081,009	3,631,261
Shareholders’ equity:
Common stock, par value $.01 per share, 200,000,000 shares authorized; 54,734,817 and 54,310,484 shares issued and outstanding, respectively	547	543
Additional paid-in capital	763,935	761,550
Accumulated other comprehensive income (loss)	21,316	-33,816
Accumulated deficit	-288,154	-252,059
Total shareholders' equity	607,302	585,876
Total liabilities and shareholders’ equity	3,688,311	4,217,137
Series A Preferred Stock [Member]
Shareholders’ equity:
Preferred Stock, par value $.01 per share, 8.5% Series A Cumulative Redeemable; 8,000,000 shares authorized; 2,300,000 shares issued and outstanding ($57,500 aggregate liquidation preference)	55,407	55,407
Preferred Stock, par value $.01 per share, 7.625% Series B Cumulative Redeemable; 7,000,000 shares authorized 2,250,000 shares issued and outstanding ($56,250 aggregate liquidation preference)	55,407	55,407
Series B Preferred Stock [Member]
Shareholders’ equity:
Preferred Stock, par value $.01 per share, 8.5% Series A Cumulative Redeemable; 8,000,000 shares authorized; 2,300,000 shares issued and outstanding ($57,500 aggregate liquidation preference)	54,251	54,251
Preferred Stock, par value $.01 per share, 7.625% Series B Cumulative Redeemable; 7,000,000 shares authorized 2,250,000 shares issued and outstanding ($56,250 aggregate liquidation preference)	$54,251	$54,251

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
ASSETS
Pledged MBS	$3,265,979	$3,873,584
Common stock, par value	$0.01	$0.01
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares, Issued	54,739,111	54,310,484
Common stock, shares outstanding	54,739,111	54,310,484
Series A Preferred Stock [Member]
ASSETS
Preferred Stock, Par Value Per Share	$0.01	$0.01
Preferred Stock, Shares Authorized	8,000,000	8,000,000
Preferred Stock, Shares Issued	2,300,000	2,300,000
Preferred Stock, Shares Outstanding	2,300,000	2,300,000
Preferred Stock, aggregate liquidation preference	57,500	57,500
Series B Preferred Stock [Member]
ASSETS
Preferred Stock, Par Value Per Share	$0.01	$0.01
Preferred Stock, Shares Authorized	7,000,000	7,000,000
Preferred Stock, Shares Issued	2,250,000	2,250,000
Preferred Stock, Shares Outstanding	2,250,000	2,250,000
Preferred Stock, aggregate liquidation preference	$56,250	$56,250

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Interest income:
Mortgage-backed securities	$102,881	$123,629	$107,728
Mortgage loans held for investment	2,763	3,503	5,820
Total interest income	105,644	127,132	113,548
Interest expense:
Repurchase agreements	25,821	38,102	33,789
Non recourse collateralized financing	94	926	1,358
Total interest expense	25,915	39,028	35,147
Net interest income	79,729	88,104	78,401
Provision for loan losses	0	-261	-192
Gain (loss) on derivative instruments, net	-53,393	-10,076	-908
Gain (loss) on sale of investments, net	16,223	3,354	8,461
Fair value adjustments, net	208	-652	735
Other income, net	1,046	658	281
General and administrative expenses:
Compensation and benefits	-9,509	-7,004	-7,635
Other general and administrative	-6,498	-6,054	-5,101
Net income (loss)	27,806	68,069	74,042
Preferred Stock Dividends	-9,176	-7,902	-2,036
Net income to common shareholders	18,630	60,167	72,006
Change in fair value of available-for-sale investments	64,567	-113,343	75,377
Reclassification adjustment for (gain) loss on sale of investments, net	-16,223	-3,354	-5,319
Change in fair value of cash flow hedges	0	16,381	-28,740
Reclassification adjustment for cash flow hedges (including de-designated hedges)	6,788	13,989	14,448
Other comprehensive (loss) income	55,132	-86,327	55,766
Comprehensive income (loss) to common shareholders	$73,762	($26,160)	$127,772
Weighted average common shares - basic and diluted	54,701,485	54,647,643	53,146,416
Net income per common share - basic and diluted	$0.34	$1.10	$1.35

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity Statement (USD $)	Total	Preferred Stock Including Additional Paid in Capital [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Retained Earnings [Member]	Shareholders' Equity [Member]
In Thousands
Total shareholders' equity, beginning balance at Dec. 31, 2012
Stock issuance			$7	$7,548
Granting and vesting of restricted stock			3	2,376
Amortization of stock issuance costs				-119
Adjustments for tax withholding on share-based compensation			-1	-545
Net income (loss)	68,069
Other comprehensive (loss) income	-86,327
Total shareholders' equity, ending balance at Dec. 31, 2013	585,876	0	404	634,683	-3,255	-260,483	371,349
Stock issuance		0	1	251			252
Granting and vesting of restricted stock			4	2,715			2,719
Amortization of stock issuance costs				-75			-75
Adjustments for tax withholding on share-based compensation			-1	-506			-507
Net income (loss)	27,806					27,806	27,806
Dividends on preferred stock						-9,176	-9,176
Dividends on common stock						-54,725	-54,725
Other comprehensive (loss) income	55,132				55,132		55,132
Total shareholders' equity, ending balance at Dec. 31, 2014	$607,302	$109,658	$547	$763,935	$21,316	($288,154)	$607,302

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities:
Net income (loss)	$27,806	$68,069	$74,042
Adjustments to reconcile net income to cash provided by operating activities:
Decrease (increase) in accrued interest receivable	546	1,370	-10,464
(Decrease) increase in accrued interest payable	-600	-347	730
Provision for loan losses	0	261	192
Loss (gain) on derivative instruments, net	53,393	10,076	908
Loss (gain) on sale of investments, net	-16,223	-3,354	-8,461
Fair value adjustments, net	-208	652	-735
Amortization of investment premiums, net	137,837	128,865	91,622
Other amortization and depreciation	8,900	7,743	-1,092
Stock-based compensation expense	2,719	2,314	1,712
Other operating activities	381	-6,889	934
Net cash and cash equivalents provided by operating activities	214,551	208,760	149,388
Investing activities:
Purchase of investments	-599,381	-1,419,060	-2,639,909
Principal payments received on investments	518,303	913,210	679,635
Proceeds from sales of investments	503,918	358,090	231,145
Principal payments received on mortgage loans held for investment, net	16,787	15,828	40,830
Investment in limited partnership	-4,000	0	0
Net payments on derivatives not designated as hedges	11,415	39,097	0
Other investing activities	-7	5,891	-2,893
Net cash and cash equivalents used in investing activities	424,205	-165,138	-1,691,192
Financing activities:
(Repayments of) borrowings under repurchase agreements, net	-567,887	16,209	1,470,170
Principal payments on non-recourse collateralized financing	-2,167	-17,840	-40,626
Increase in restricted cash	-28,878	-13,346	0
Proceeds from issuance of preferred stock	0	54,251	55,407
Proceeds from issuance of common stock	177	7,436	123,868
Cash paid for repurchases of common stock	0	-6,934	-921
Payments Related to tax withholding for share-based compensation	-507	-545	0
Dividends paid	-64,880	-69,332	-59,061
Net cash and cash equivalents provided by (used in) financing activities	-664,142	-30,101	1,548,837
Net increase (decrease) in cash and cash equivalents	-25,386	13,521	7,033
Cash and cash equivalents at beginning of period	69,330	55,809	48,776
Cash and cash equivalents at end of period	43,944	69,330	55,809
Supplemental Disclosure of Cash Activities:
Cash paid for interest	$19,445	$33,517	$34,035

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Organization and Summary of Significant Accounting Policies	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 mortgage-backed securities ("MBS") 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").
	Basis of Presentation
	The accompanying consolidated financial statements of Dynex Capital, Inc. and its qualified real estate investment trust ("REIT") subsidiaries and its taxable REIT subsidiary (together, "Dynex" or the "Company") have been prepared in accordance with the generally accepted accounting principles in the United States ("GAAP") and the instructions to the Annual Report on Form 10-K and Article 3 of Regulation S-X promulgated by the Securities and Exchange Commission (the "SEC").
	Reclassifications
	Certain items in the prior periods' consolidated financial statements have been reclassified to conform to the current year’s presentation. The Company's consolidated balance sheet as of December 31, 2013 now presents its "securitized mortgage loans, net" and "other investments, net" together as "mortgage loans held for investment, net ". In addition, the Company has combined the presentation of its consolidated statements of income and its consolidated statements of other comprehensive income together as one financial statement which is now titled "consolidated statements of comprehensive income". The Company's "interest income - securitized mortgage loans" and "interest income-other investments" on its consolidated statements of income for the years ended December 31, 2013 and December 31, 2012 are now presented together as "interest income-mortgage loans held for investment, net" on its consolidated statements of comprehensive income for the years ended December 31, 2013 and December 31, 2012. The Company's "amortization and depreciation" on its consolidated statements of cash flows for the years ended December 31, 2013 and December 31, 2012 are now presented as "amortization of investment premiums, net" and "other amortization and depreciation". These presentation changes have no effect on reported total assets, total liabilities, results of operations, or cash flow activities.
	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. All intercompany accounts and transactions have been eliminated in consolidation.
	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. Additional information regarding the accounting policy for the Company's securitized mortgage loans is provided below under "Mortgage Loans Held for Investment, Net ".
	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, fair value measurements of its investments, other-than-temporary impairments, contingencies, and amortization of premiums and discounts. 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 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 gain 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 ASC Topic 740. The Company records these liabilities, if any, to the extent they are deemed more likely than not to have been incurred.
	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 counterparties.
	Mortgage-Backed Securities
	In accordance with ASC Topic 320, the Company has designated its investments in MBS as available-for-sale ("AFS"). All of the Company’s MBS are recorded at fair value on the consolidated balance sheet. Changes in fair value for the Company's AFS securities are reported in other comprehensive income ("OCI") until each security is collected, disposed of, or 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 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 Agency MBS as well as any non-Agency MBS rated 'AA' and higher at the time of purchase are amortized into interest income over the expected life of such securities using the effective yield method and adjustments to premium amortization are made for actual cash payments as well as changes in projected future cash payments in accordance with ASC Topic 310-20. The Company's projections of future cash payments are based on input and analysis received from external sources and internal models, and includes assumptions about the amount and timing of credit losses, loan prepayment rates, fluctuations in interest rates, 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 holds non-Agency MBS that were rated less than 'AA' at the time of purchase by at least one national rating agency. These non-Agency MBS were purchased at discounts to their par value, which management does not believe to be substantial. The Company accretes the discount into income over the security's expected life, which reflects management's estimate of the security's projected cash flows in accordance with ASC Topic 325-40. 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 8 for further discussion of MBS fair value measurements.
	Other-than-Temporary Impairment. 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 3 for additional information related to the Company's evaluation for OTTI.
	Mortgage Loans Held for Investment, Net
	The Company originated or purchased mortgage loans from 1992 through 1998, and these mortgage loans are reported at amortized cost in accordance with ASC Topic 310-10. A portion of these loans is pledged as collateral to support the repayment of one remaining class of a securitization financing bond issued by the Company in 2002. The associated securitization financing bond is treated as debt of the Company and is presented as "non-recourse collateralized financing" on the consolidated balance sheet. Securitized mortgage loans can only be sold subject to the lien of the respective securitization financing indenture. An allowance has been established for currently existing and probable losses on the Company's mortgage loans held for investment.
	Investment in Limited Partnership
	The Company is a limited partner with a less than 50% interest in a limited partnership for which it does not have substantive participating or kick-out rights that overcome the general partner's presumption of control. The Company accounts for its investment in this limited partnership using the equity method of accounting, which requires initially recording an investment in the equity of an investee at cost and subsequently adjusting the carrying amount of the investment to recognize the investor's share of the earnings or losses, capital contributions and distributions, and other changes in equity.
	Repurchase Agreements
	Repurchase agreements 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, which currently include interest rate swaps and Eurodollar futures, are accounted for in accordance with ASC Topic 815, which requires an entity to recognize all derivatives as either assets or liabilities in the balance sheet and to measure those instruments at fair value. All periodic interest costs and other changes in fair value, including gains and losses recognized upon termination, associated with derivative instruments are recorded in "gain (loss) on derivative instruments, net" on the Company's consolidated statement of comprehensive income.
	Effective June 30, 2013, the Company discontinued cash flow hedge accounting for derivative instruments which had previously been accounted for as cash flow hedges under ASC Topic 815. Activity up to and including June 30, 2013 for those agreements previously designated as cash flow hedges was recorded in accordance with cash flow hedge accounting as prescribed by ASC Topic 815, which states that the effective portion of the hedge relationship on an instrument designated as a cash flow hedge is reported in the current period's other comprehensive income while the ineffective portion is immediately reported as a component of the current period’s net income. The balance remaining in AOCI related to the de-designated cash flow hedges is amortized into the Company's net income as a portion of "interest expense" over the remaining life of the interest rate swap agreements. Subsequent to June 30, 2013, changes in the fair value of the Company's derivative instruments, plus periodic settlements, are recorded in the Company's net income as a portion of "gain (loss) on derivative instruments, net".
	Although MBS have characteristics that meet the definition of a derivative instrument, ASC Topic 815 specifically excludes these instruments from its scope because they are accounted for as debt securities under ASC Topic 320.
	Share-Based Compensation
	Pursuant to the Company’s 2009 Stock and Incentive Plan ("SIP"), 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 share-based based 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.
	Contingencies
	In the normal course of business, there are 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 in accordance with ASC Topic 450, which states that a liability is recognized 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. As of December 31, 2014, the Company does not have any contingencies for which it believes a probable loss has been incurred.
	Recent Accounting Pronouncements
	In June 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-11, Transfers and Servicing (Topic 860): Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures, which changes the accounting for repurchase-to-maturity transactions and repurchase financing arrangements. The guidance eliminates sale accounting for repurchase-to-maturity transactions and supersedes the guidance under which a transfer of a financial asset and a contemporaneous repurchase financing could be accounted for on a combined basis as a forward agreement, which has resulted in outcomes referred to as off-balance-sheet accounting. All of the Company's repurchase agreement transactions are accounted for as secured borrowings; therefore the accounting changes required by ASU No. 2014-11 do not impact the Company's consolidated financial statements. ASU No. 2014-11 also requires two additional disclosures about repurchase agreements and other similar transactions. The first disclosure requires an entity to disclose information on transfers accounted for as sales in transactions that are economically similar to repurchase agreements. The Company does not account for any of its repurchase agreement transactions as sales; therefore this new disclosure does not impact the Company's current disclosures. The second disclosure requires the following disclosures for repurchase agreements, securities lending transactions, and repurchase-to-maturity transactions that are accounted for as secured borrowings: a disaggregation of the gross obligation by the class of collateral pledged; the remaining contractual tenor of the agreements; and a discussion of the potential risks associated with the agreements and the related collateral pledged, including obligations arising from a decline in the fair value of the collateral pledged and how those risks are managed. The Company already provides these disclosures in its "Notes to the Consolidated Financial Statements" and within "Liquidity and Capital Resources" in Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" of this Annual Report on Form 10-K. The amendments provided in ASU No. 2014-11 are effective for public business entities for the first interim or annual period beginning after December 15, 2014. ASU No. 2014-11 will not have a material impact on the Company's consolidated financial statements.
	In addition, the FASB issued ASU No. 2014-12, Compensation - Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. The amendments in this ASU are effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. The Company has not issued and does not anticipate issuing any share-based payments with terms that require a performance-based target; therefore this ASU will not have an impact on the Company's consolidated financial statements.
	The FASB issued ASU No. 2014-13, Consolidation (Topic 810): Measuring the Financial Assets and the Financial Liabilities of a Consolidated Collateralized Financing Entity, which provides an alternative to Topic 820, Fair Value Measurement, for measuring the financial assets and the financial liabilities of a consolidated collateralized financing entity to eliminate the difference in the fair value of the financial assets of a collateralized financing entity, as determined under GAAP, when they differ from the fair value of its financial liabilities even when the financial liabilities have recourse only to the financial assets. When the measurement alternative is elected, both the financial assets and the financial liabilities of the collateralized financing entity should be measured using the more observable of the fair value of the financial assets or the fair value of the financial liabilities. The amendments clarify that when the measurement alternative is elected, a reporting entity's consolidated net income (loss) should reflect the reporting entity's own economic interests in the collateralized financing entity, including; (1) changes in the fair value of the beneficial interests retained by the reporting entity, and (2) beneficial interests that represent compensation for services. The measurement alternative provided in ASU No. 2014-13 may be applied using a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the annual period of adoption. The amendments may also be applied retrospectively to all relevant prior periods beginning with the annual period in which ASU No. 2009-17 was initially adopted. ASU No. 2014-13 is effective for public entities for annual periods, and interim periods within those annual periods, beginning after December 15, 2015, and early adoption is permitted as of the beginning of an annual period. Management has evaluated ASU No. 2014-13 and has determined that if the Company elects to adopt this measurement alternative in the future for its currently existing consolidated collateralized financing entity, it will not have a material impact on the Company's consolidated financial statements.
	The FASB issued ASU No. 2014-15, Presentation of Financial Statements-Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern, which provides guidance about management's responsibility under GAAP to evaluate whether there is substantial doubt about an organization's ability to continue as a going concern and to provide related footnote disclosures. Specifically, the ASU (1) provides a definition of the term "substantial doubt", (2) requires an evaluation by management every reporting period including interim periods, (3) provides principles for considering the mitigating effect of management's plans, (4) requires certain disclosures when substantial doubt exists regardless of the success of any mitigating plans or actions, (5) requires an express statement and other disclosures when substantial doubt is not alleviated, and (6) requires an assessment for a period of one year after the date that the financial statements are issued. The amendments in this ASU are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. Management intends to comply with the requirements set forth in ASU No. 2014-15.

Net_Income_Per_Common_Share

Net Income Per Common Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share, Basic and Diluted [Abstract]
Net Income per Common Share	NET INCOME PER COMMON SHARE
	Because the Company's Series A Cumulative Redeemable Preferred Stock and Series B Cumulative Redeemable 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 is excluded from the calculation of diluted net income per common share. 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 per 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 is converted to one equal share of common stock.
	The following table presents the calculation of the numerator and denominator for both basic and diluted net income per common share for the periods indicated:
		Year Ended
		December 31, 2014					December 31, 2013					31-Dec-12
		Net			Weighted-Average Common Shares		Net			Weighted-		Net			Weighted-
		Income					Income			Average		Income			Average
										Common					Common
										Shares					Shares
	Net income	$	27,806				$	68,069				$	74,042
	Preferred stock dividends	(9,176		)			(7,902		)			(2,036		)
	Net income to common shareholders	18,630			54,701,485		60,167			54,647,643		72,006			53,146,416
	Effect of dilutive instruments	—			—		—			—		—			—
	Diluted net income to common shareholders	$	18,630		54,701,485		$	60,167		54,647,643		$	72,006		53,146,416
	Net income per common share:
	Basic and diluted (1)				$	0.34				$	1.1				$	1.35
	-1	For the year ended December 31, 2012, the calculation of diluted net income per common share excludes the effect of 15,000 unexercised stock option awards because their inclusion would have been anti-dilutive. The Company did not have any potentially dilutive securities outstanding for the years ended December 31, 2014 or December 31, 2013.

Mortgage_Backed_Securities_Mor

Mortgage Backed Securities Mortgage backed securities (Notes)	12 Months Ended
	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Mortgage-backed securities	MORTGAGE-BACKED SECURITIES
	The majority of the Company's MBS are pledged as collateral to cover initial and variation margins for the Company's repurchase agreements and derivative instruments. The following tables provide detail by type of investment for the Company’s MBS designated as AFS for the periods indicated:
		December 31, 2014
		Par			Net Premium (Discount)			Amortized Cost				Gross Unrealized Gain				Gross Unrealized Loss			Fair Value		WAC (1)
	RMBS:
	Agency	$	2,086,807		$	113,635		$	2,200,442			$	8,473			$	(22,215	)	$	2,186,700	3.09	%
	Non-Agency	22,432			(17		)	22,415				107				(74		)	22,448		3.83	%
		2,109,239			113,618			2,222,857				8,580				(22,289		)	2,209,148
	CMBS:
	Agency	301,943			18,042			319,985				15,288				(76		)	335,197		5.21	%
	Non-Agency	210,358			(8,520		)	201,838				6,679				(479		)	208,038		4.33	%
		512,301			9,522			521,823				21,967				(555		)	543,235
	CMBS IO (2):
	Agency	—			426,564			426,564				12,252				(79		)	438,737		0.8	%
	Non-Agency	—			319,280			319,280				6,069				(230		)	325,119		0.72	%
		—			745,844			745,844				18,321				(309		)	763,856
	Total AFS securities:	$	2,621,540		$	868,984		$	3,490,524			$	48,868			$	(23,153	)	$	3,516,239
	-1	The current weighted average coupon ("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 Agency CMBS IO and non-Agency CMBS IO was $10,460,113 and $7,868,896, respectively, as of December 31, 2014.
		31-Dec-13
		Par			Net Premium (Discount)			Amortized Cost				Gross Unrealized Gain				Gross Unrealized Loss			Fair Value		WAC (1)
	RMBS:
	Agency	$	2,591,568		$	154,220		$	2,745,788			$	6,104			$	(59,742	)	$	2,692,150	3.22	%
	Non-Agency	13,845			(338		)	13,507				338				(80		)	13,765		4.61	%
		2,605,413			153,882			2,759,295				6,442				(59,822		)	2,705,915
	CMBS:
	Agency (2)	273,830			19,061			292,891				10,793				(900		)	302,784		5.07	%
	Non-Agency	375,703			(18,277		)	357,426				15,366				(3,511		)	369,281		5.1	%
		649,533			784			650,317				26,159				(4,411		)	672,065
	CMBS IO (3):
	Agency	—			453,766			453,766				9,895				(3,334		)	460,327		0.83	%
	Non-Agency	—			150,518			150,518				2,618				(1,999		)	151,137		0.66	%
		—			604,284			604,284				12,513				(5,333		)	611,464
	Total AFS securities:	$	3,254,946		$	758,950		$	4,013,896			$	45,114			$	(69,566	)	$	3,989,444
	-1	The current weighted average coupon ("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	As of December 31, 2013, the Company had Agency CMBS with an amortized cost of $26,920 and fair value of $28,717 which were designated as trading securities and are not included in this table. The Company changed the designation of these Agency CMBS to AFS during the three months ended June 30, 2014. Changes in the fair value of these MBS while they were designated as trading were recognized in net income within "fair value adjustments, net". Changes in the fair value of these MBS, which are now designated as AFS, are recognized in "other comprehensive income". As of December 31, 2014, the Company does not have any MBS designated as trading.
	-3	The notional balance for the Agency CMBS IO and non-Agency CMBS IO was $10,160,502 and $4,274,957, respectively, as of December 31, 2013.
	The Company received proceeds of $503,918, $357,892, and $125,108 for the sale of MBS during the years ended December 31, 2014, December 31, 2013, and December 31, 2012, respectively. The following table presents the gross realized gains (losses) of those sales included in "gain on sale of investments, net" on the Company's consolidated statements of comprehensive income for the periods indicated:
		Year Ended
		December 31,
		2014			2013			2012 (1)
	($ in thousands)	Gain (Loss) Recognized			Gain (Loss) Recognized			Gain (Loss) Recognized
	Gross realized gains on sales of MBS	$	22,492		$	8,670		$	5,319
	Gross realized losses on sales of MBS	(6,269		)	(5,316		)	—
	Total included in gain on sale of investments, net	$	16,223		$	3,354		$	5,319
	-1	Total gain on sale of investments, net for the year ended December 31, 2012 includes $2,072 and $1,070 of gains recognized from the Company's liquidation of a securitized mortgage loan and an investment in Freddie Mac Unsecured Senior Notes, respectively, which are not included in this table.
	The following table presents certain information for those Agency MBS in an unrealized loss position as of December 31, 2014 and December 31, 2013:
		31-Dec-14								31-Dec-13
		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	$	322,741		$	(879	)	24		$	1,912,937			$	(43,543	)		150
	Non-Agency MBS	111,778			(625		)	24		162,558				(5,435		)		39
	Continuous unrealized loss position for 12 months or longer:
	Agency MBS	$	1,321,323		$	(21,491	)	113		$	670,402			$	(20,433	)		67
	Non-Agency MBS	18,037			(159		)	5		6,310				(155		)		6
	Because the principal related to Agency MBS are 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. This assessment is based on the amount of the unrealized loss and significance of the related investment as well as the Company’s current leverage and anticipated liquidity. Based on this analysis, the Company has determined that the unrealized losses on its Agency MBS as of December 31, 2014 and December 31, 2013 were temporary.
	The Company also 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 these non-Agency MBS and the seasoning of the mortgage loans collateralizing these securities as well as the estimated future cash flows which include projected losses. The Company performed this evaluation for the 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 December 31, 2014 or December 31, 2013.

Mortgage_Loans_Held_for_Invest

Mortgage Loans Held for Investment, Net and Related Financing Mortgage Loans Held for Investment, Net (Notes)	12 Months Ended
	Dec. 31, 2014
Mortgage Loans Held for Investment, Net [Abstract]
Mortgage Loans Held for Investment, Net [Text Block]	The Company's mortgage loans held for investment, net consist of securitized and unsecuritized mortgage loans originated or purchased by the Company from 1992 through 1998. The following table provides detail by type of collateral as of the periods indicated:
		31-Dec-14			31-Dec-13
	Single-family mortgage loans held for investment, amortized cost	$	30,214		$	35,328
	Commercial mortgage loans held for investment, amortized cost	9,736			20,352
	Allowance for loan losses	(250		)	(257		)
	Total mortgage loans held for investment, net	$	39,700		$	55,423
	Commercial securitized mortgage loans are evaluated individually for impairment when the debt service coverage ratio on the mortgage loan is less than 1:1 or when the mortgage loan is delinquent. Commercial mortgage loans not evaluated for individual impairment are evaluated for a general allowance. There were no securitized commercial mortgage loans identified as seriously delinquent (60 or more days past due) on the Company's consolidated balance sheets as of December 31, 2014 or as of December 31, 2013.
	Single-family mortgage loans are considered homogeneous and are evaluated on a pool basis for a general allowance. The unpaid principal balance of the Company's securitized single-family mortgage loans identified as seriously delinquent as of December 31, 2014 was $2,221 compared to $2,758 as of December 31, 2013. The Company continues to accrue interest on its seriously delinquent securitized single-family mortgage loans because the primary servicer continues to advance the interest and/or principal due on the loan.
	The Company considers various factors in determining its specific and general allowance requirements, including whether a loan is delinquent, the Company’s historical experience with similar types of loans, historical cure rates of delinquent loans, and historical and anticipated loss severity of the mortgage loans as they are liquidated. The factors may differ by mortgage loan type (e.g., single-family versus commercial) and collateral type (e.g., multifamily versus office property). The allowance for loan losses is evaluated and adjusted periodically by management based on the actual and estimated timing and amount of probable credit losses, using the above factors, as well as industry loss experience.
	The majority of the Company's mortgage loans held for investment, net are securitized mortgage loans, of which $11,902 of principal is pledged as collateral for an outstanding class of the Company's single-family securitization financing bond, which is recorded on the Company's balance sheet as "non-recourse collateralized financing". The interest rate on this bond is based on 1-month LIBOR plus 0.30% and has an estimated life remaining of less than 3 years as of December 31, 2014. The principal balance outstanding as of December 31, 2014 is $10,967 compared to $13,134 as of December 31, 2013.
Allowance for Credit Losses [Text Block]	Commercial securitized mortgage loans are evaluated individually for impairment when the debt service coverage ratio on the mortgage loan is less than 1:1 or when the mortgage loan is delinquent. Commercial mortgage loans not evaluated for individual impairment are evaluated for a general allowance. There were no securitized commercial mortgage loans identified as seriously delinquent (60 or more days past due) on the Company's consolidated balance sheets as of December 31, 2014 or as of December 31, 2013.
	Single-family mortgage loans are considered homogeneous and are evaluated on a pool basis for a general allowance. The unpaid principal balance of the Company's securitized single-family mortgage loans identified as seriously delinquent as of December 31, 2014 was $2,221 compared to $2,758 as of December 31, 2013. The Company continues to accrue interest on its seriously delinquent securitized single-family mortgage loans because the primary servicer continues to advance the interest and/or principal due on the loan.
	The Company considers various factors in determining its specific and general allowance requirements, including whether a loan is delinquent, the Company’s historical experience with similar types of loans, historical cure rates of delinquent loans, and historical and anticipated loss severity of the mortgage loans as they are liquidated. The factors may differ by mortgage loan type (e.g., single-family versus commercial) and collateral type (e.g., multifamily versus office property). The allowance for loan losses is evaluated and adjusted periodically by management based on the actual and estimated timing and amount of probable credit losses, using the above factors, as well as industry loss experience.

Repurchase_Agreements_Notes

Repurchase Agreements (Notes)	12 Months Ended
	Dec. 31, 2014
Disclosure of Repurchase Agreements [Abstract]
Repurchase Agreements	REPURCHASE AGREEMENTS
	The following tables present the components of the Company’s repurchase agreements as of December 31, 2014 and December 31, 2013 by the fair value and type of securities pledged as collateral:
		December 31, 2014
	Collateral Type	Balance			Weighted			Fair Value of
					Average Rate			Collateral Pledged
	Agency RMBS	$	1,977,338		0.39	%		2,064,704
	Non-Agency RMBS	17,594			1.57	%		21,787
	Agency CMBS	253,857			0.36	%		291,103
	Non-Agency CMBS	114,895			1.15	%		140,216
	Agency CMBS IOs	372,609			0.92	%		430,638
	Non-Agency CMBS IO	266,983			1.04	%		315,149
	Securitization financing bonds	9,834			1.51	%		11,000
		$	3,013,110		0.55	%		$	3,274,597
		December 31, 2013
	Collateral Type	Balance			Weighted			Fair Value of Collateral Pledged
					Average Rate
	Agency RMBS	$	2,522,503		0.42	%		2,598,158
	Non-Agency RMBS	10,569			1.8	%		12,746
	Agency CMBS	246,849			0.39	%		306,318
	Non-Agency CMBS	303,674			1.27	%		367,859
	Agency CMBS IOs	369,948			1.16	%		449,072
	Non-Agency CMBS IOs	106,803			1.27	%		136,227
	Securitization financing bonds	20,651			1.59	%		19,686
	Deferred costs	(243		)	n/a			n/a
		$	3,580,754		0.61	%		$	3,890,066
	The combined weighted average original term to maturity for the Company’s repurchase agreements was 144 days as of December 31, 2014 compared to 114 days as of December 31, 2013. The following table provides a summary of the original maturities as of December 31, 2014 and December 31, 2013:
	Original Maturity	December 31,			December 31,
		2014			2013
	Less than 30 days	$	250,635		$	4,736
	30 to 90 days	617,399			1,176,631
	91 to 180 days	904,830			1,439,225
	181 to 364 days	1,030,569			960,405
	1 year or longer	209,677			—
	Deferred costs	—			(243		)
		$	3,013,110		$	3,580,754
	As of December 31, 2014, shareholders' equity at risk did not exceed 10% for any of the Company's counterparties. The Company had $247,115 of its repurchase agreement balance as of December 31, 2014 outstanding under a two-year repurchase facility with Wells Fargo Bank National Association. Subsequent to December 31, 2014, this facility was amended to increase its aggregate maximum borrowing capacity to $300,000 and to extend the maturation to August 6, 2016, 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 December 31, 2014 was 1.01%.
	As of December 31, 2014, the Company had repurchase agreement amounts outstanding with 20 of its 33 available 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, 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 compliance with all covenants as of December 31, 2014.
	Please see Note 7 for the Company's disclosures related to offsetting assets and liabilities.

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	DERIVATIVES
	The Company utilizes derivative instruments to economically hedge a portion of its exposure to market risks, primarily interest rate risk. The Company primarily uses pay-fixed interest rate swaps and Eurodollar contracts to hedge its exposure to changes in interest rates and uses receive-fixed interest rate swaps to offset a portion of its pay-fixed interest rate swaps in order to manage its overall hedge position. The objective of the Company's risk management strategy is 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 the Company's earnings from rising interest rates. 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 Company’s derivative instruments treated as trading instruments on its consolidated balance sheet as of the dates indicated:
			December 31, 2014
			Derivative Assets								Derivative Liabilities
	Trading Instruments		Fair Value				Notional				Fair Value				Notional
	Interest rate swaps		$	5,727			$	440,000			$	(3,002	)		$	485,000
	Eurodollar futures (1)		—				—				(32,896		)		16,600,000
	Total		$	5,727			$	440,000			$	(35,898	)		$	17,085,000
			December 31, 2013
			Derivative Assets								Derivative Liabilities
	Trading Instruments		Fair Value				Notional				Fair Value				Notional
	Interest rate swaps		$	18,488			$	575,000			$	(1,336	)		$	215,000
	Eurodollar futures (1)		—				—				(5,345		)		9,000,000
	Total		$	18,488			$	575,000			$	(6,681	)		$	9,215,000
	-1	The Eurodollar futures aggregate notional amount represents the total notional of the 3-month contracts with expiration dates from 2015 to 2020. The maximum notional outstanding for any future 3-month period did not exceed $1,300,000 as of December 31, 2014 and $1,175,000 as of December 31, 2013.
	The following table summarizes the contractual maturities remaining for the Company’s outstanding interest rate swap agreements as of December 31, 2014:
	Remaining Maturity		Pay-Fixed Interest Rate Swaps				Pay-Fixed			Receive Fixed Interest Rate Swaps				Receive-Fixed
							Weighted-Average Rate(1)							Weighted-Average Rate
	37-48 months		$	185,000			0.92	%		$	—			—	%
	49-60 months		235,000				1.45	%		250,000				1.91	%
	61-72 months		25,000				1.61	%		—				—	%
	73-84 months		25,000				2.19	%		—				—	%
	85-96 months		—				—	%		—				—	%
	97-108 months		30,000				1.93	%		—				—	%
	109-120 months		150,000				2.17	%		25,000				2.71	%
	The following table summarizes the volume of activity related to derivative instruments for the periods indicated:
	For the year ended December 31, 2014:	Beginning of Period Notional Amount				Additions				Settlement, Termination, Expiration or Exercise				End of Period Notional Amount
	Receive-fixed interest rate swaps	$	—			$	275,000			$	—			$	275,000
	Pay-fixed interest rate swaps	790,000				75,000				(215,000		)		650,000
	Eurodollar futures	9,000,000				7,600,000				—				16,600,000
		$	9,790,000			$	7,950,000			$	(215,000	)		$	17,525,000
	The table below provides detail of the Company's "gain (loss) on derivative instruments, net" by type of interest rate derivative for the periods indicated:
			Year Ended
			December 31,
	Type of Derivative Instrument		2014				2013				2012
	Receive-fixed interest rate swaps		$	4,912			$	—			$	—
	Pay-fixed interest rate swaps		(30,754		)		9,315				(908		)
	Eurodollar futures		(27,551		)		(19,391		)		—
	Gain (loss) on derivative instruments, net		$	(53,393	)		$	(10,076	)		$	(908	)
	Effective June 30, 2013, the Company de-designated certain interest rate swap agreements as cash flow hedges under ASC Topic 815. There is a net unrealized loss of $2,577 remaining in AOCI on the Company's consolidated balance sheet as of December 31, 2014 which represents the activity related to these 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 a portion of "interest expense" over the remaining contractual life of the agreements. Because of differing market values and maturities at the time of cash flow hedge de-designation, the balance remaining in AOCI is comprised of both unrealized gains and unrealized losses which will not be recognized in net income equally over time. All forecasted transactions associated with interest rate swap agreements previously designated as cash flow hedges are expected to occur. No amounts have been reclassified to net income in any period in connection with forecasted transactions that are no longer considered probable of occurring. The Company estimates the portion of existing net unrealized loss on discontinued cash flow hedges expected to be reclassified to net income within the next 12 months is $3,460.
	The table below describes the components of the reclassification adjustments out of AOCI related to certain interest rate swaps that were formerly designated as cash flow hedges and recognized as a portion of "interest expense" on the Company statements of comprehensive income for the periods indicated:
		Year Ended
		December 31,
		2014				2013				2012
	Reclassification adjustment due to amortization of de-designated cash flow hedges	$	6,788			$	5,193			$	—
	Reclassification adjustment due to recognition of interest expense from cash flow hedges	—				8,796				14,448
	Total reclassification adjustment related to cash flow hedges	$	6,788			$	13,989			$	14,448
	Many of the Company's interest rate swaps were entered into under bilateral agreements which contain various covenants related to the Company’s credit risk. Specifically, if the Company defaults on any of its indebtedness, including those circumstances whereby repayment of the indebtedness has not yet been accelerated by the lender, or is declared in default of any of its covenants with any counterparty, then the Company could also be declared in default under the bilateral agreement. Additionally, these agreements allow those counterparties to require settlement of its outstanding derivative transactions if the Company fails to earn GAAP net income excluding derivative gains and losses greater than one dollar as measured on a rolling two quarter basis. These interest rate agreements also contain provisions whereby, if the Company fails to maintain a minimum net amount of shareholders’ equity, then the Company may be declared in default on its derivative obligations. The Company was in compliance with all covenants under bilateral agreements on December 31, 2014.
	Please see Note 7 for the Company's disclosures related to offsetting assets and liabilities.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments (Notes)	12 Months Ended
	Dec. 31, 2014
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 following table presents the fair value of the Company’s assets and liabilities presented on its consolidated balance sheets, 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:
		December 31, 2014
		Fair Value				Level 1 - Unadjusted Quoted Prices in Active Markets			Level 2 - Observable Inputs			Level 3 - Unobservable Inputs
	Assets:
	Mortgage-backed securities	$	3,516,239			$	—		$	3,472,282		$	43,957
	Derivative assets	5,727				—			5,727			—
	Total assets carried at fair value	$	3,521,966			$	—		$	3,478,009		$	43,957
	Liabilities:
	Derivative liabilities	$	35,898			$	32,896		$	3,002		$	—
	Total liabilities carried at fair value	$	35,898			$	32,896		$	3,002		$	—
		December 31, 2013
		Fair Value				Level 1 - Unadjusted Quoted Prices in Active Markets			Level 2 - Observable Inputs			Level 3 - Unobservable Inputs
	Assets:
	Mortgage-backed securities	$	4,018,161			$	—		$	3,944,681		$	73,480
	Derivative assets	18,488				—			18,488			—
	Total assets carried at fair value	$	4,036,649			$	—		$	3,963,169		$	73,480
	Liabilities:
	Derivative liabilities	$	6,681			$	5,345		$	1,336		$	—
	Total liabilities carried at fair value	$	6,681			$	5,345		$	1,336		$	—
	The Company did not have assets or liabilities measured at fair value on a non-recurring basis as of December 31, 2014 or December 31, 2013.
	The Company's derivative assets and liabilities include interest rate swaps and Eurodollar futures. Interest rate swaps are valued 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. Eurodollar futures are valued based on closing exchange prices on these contracts. Accordingly, these financial futures are classified as Level 1.
	Agency MBS, as well a majority of non-Agency MBS, are substantially similar to securities that either are currently actively traded or have been recently traded in their respective market. Their fair values are derived from an average of multiple dealer quotes and thus are considered Level 2 fair value measurements. The Company’s remaining non-Agency MBS are comprised of securities for which there are not substantially similar securities that trade frequently, and their fair values are therefore considered Level 3 measurements. The Company determines the fair value of its Level 3 securities by discounting the estimated future cash flows derived from cash flow models using assumptions that are confirmed to the extent possible by third party dealers or other pricing indicators. Significant inputs into those pricing models are Level 3 in nature due to the lack of readily available market quotes. 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 would result in a significantly different fair value measurement. Generally Level 3 assets are most sensitive to the default rate and severity assumptions.
	The table below presents information about the significant unobservable inputs used in the fair value measurement for the Company's Level 3 non-Agency CMBS and RMBS as of December 31, 2014:
		Quantitative Information about Level 3 Fair Value Measurements (1)
		Prepayment Speed		Default Rate			Severity		Discount Rate
	Non-Agency CMBS	20 CPY		2	%		35	%	9.9	%
	Non-Agency RMBS	10 CPR		1	%		20	%	6.5	%
	-1	Data presented are weighted averages.
	The following table presents the activity of the instruments fair valued at Level 3 on a recurring basis during the periods indicated:
		Level 3 Fair Value
		Non-Agency CMBS				Non-Agency RMBS			Other			Total assets
	Balance as of January 1, 2013	$	100,102			$	5,118		$	25		$	105,245
	Purchases	26,021				—			—			26,021
	Sales/write-offs to net income	—				—			(25		)	(25		)
	Unrealized (loss) gain included in OCI	(6,026		)		5			—			(6,021		)
	Principal payments	(49,167		)		(2,421		)	—			(51,588		)
	(Amortization) accretion	(197		)		45			—			(152		)
	Balance as of December 31, 2013	70,733				2,747			—			73,480
	Unrealized gain (loss) included in OCI	2,317				(139		)	—			2,178
	Principal payments	(31,253		)		(1,014		)	—			(32,267		)
	Accretion	236				330			—			566
	Balance as of end of December 31, 2014	$	42,033			$	1,924		$	—		$	43,957
	The following table presents a summary of the recorded basis and estimated fair values of the Company’s financial instruments as of the dates indicated:
		December 31, 2014							December 31, 2013
		Recorded Basis				Fair Value			Recorded Basis			Fair Value
	Assets:
	Mortgage-backed securities	$	3,516,239			$	3,516,239		$	4,018,161		$	4,018,161
	Mortgage loans held for investment, net(1)	39,700				35,024			55,423			46,383
	Derivative assets	5,727				5,727			18,488			18,488
	Liabilities:
	Repurchase agreements (2)	$	3,013,110			$	3,013,110		$	3,580,754		$	3,580,997
	Non-recourse collateralized financing (1)	10,786				10,366			12,914			12,414
	Derivative liabilities	35,898				35,898			6,681			6,681
	-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 fair value of the Company's Level 3 non-Agency MBS.
	-2	The difference between the recorded basis of repurchase agreements and their fair value as of December 31, 2013 is the unamortized deferred costs remaining for the 2-year repurchase facility.

Shareholders_Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Shareholders' Equity	SHAREHOLDERS' EQUITY
	Preferred Stock
	The Company has 2,300,000 shares of its 8.50% Series A Cumulative Redeemable Preferred Stock and 2,250,000 shares of its 7.625% Series B Cumulative Redeemable Preferred Stock issued and outstanding as of December 31, 2014 (collectively, the "Preferred Stock"). 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. Except under certain limited circumstances intended to preserve the Company's REIT status, upon the occurrence of a change in control as defined in Article IIIA, Section 7(d) of the Company’s Articles of Incorporation, or to avoid the direct or indirect imposition of a penalty tax in respect of, or to protect the tax status of, any of the Company’s real estate mortgage investment conduits (“REMIC”) interests or a REMIC in which the Company may acquire an interest (as permitted by the Company’s Articles of Incorporation), the Company may not redeem the Series A Preferred Stock prior to July 31, 2017 or the Series B Preferred Stock prior to April 30, 2018. On or after these dates, at any time and from time to time, the Preferred Stock may be redeemed in whole, or in part, at the Company's option at a cash redemption price of $25.00 per share plus any accumulated and unpaid dividends. 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. 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 Company announced that it will pay its regular quarterly dividends on its Preferred Stock for the fourth quarter on January 15, 2015 to shareholders of record as of January 1, 2015.
	Common Stock
	The following table presents a summary of the changes in the number of common shares outstanding for the periods presented:
		Year Ended
		December 31,
		2014		2013
	Balance as of beginning of period	54,310,484		54,268,915
	Common stock issued under DRIP	16,753		515,257
	Common stock issued under ATM program	—		180,986
	Common stock issued or redeemed under stock and incentive plans	471,210		270,158
	Common stock forfeited for tax withholding on share-based compensation	(59,336	)	(52,385	)
	Common stock repurchased during the period	—		(872,447	)
	Balance as of end of period	54,739,111		54,310,484
	The Company had 7,416,520 shares of common stock that remain available to offer and sell through its sales agent, JMP Securities LLC, under its "at the market", or "ATM" program, as of December 31, 2014.
	The Company's Dividend Reinvestment and Share Purchase Plan ("DRIP") allows registered shareholders to automatically reinvest some or all of their quarterly common stock dividends in shares of the Company’s common stock and provides an opportunity for investors to purchase shares of the Company’s common stock, potentially at a discount to the prevailing market price. Of the 3,000,000 shares reserved for issuance under the Company's DRIP, there were 2,450,145 shares remaining for issuance as of December 31, 2014. The Company declared a fourth quarter common stock dividend of $0.25 per share payable on January 31, 2015 to shareholders of record as of December 31, 2014. There was no discount for shares purchased through the DRIP during the fourth quarter of 2014.
	In December 2014, the Company announced that its Board of Directors authorized the repurchase of up to $50,000 of its common stock through December 31, 2016. This new repurchase authorization replaces the Company's prior share repurchase program which was to expire on December 31, 2014.
	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 1,078,908 available for issuance as of December 31, 2014. Total stock-based compensation expense recognized by the Company for the year ended December 31, 2014 was $2,719 compared to $2,354 for the year ended December 31, 2013.
	The following table presents a rollforward of the restricted stock activity for the periods indicated:
		Year Ended
		December 31,
		2014		2013
	Restricted stock outstanding as of beginning of period	520,969		448,283
	Restricted stock granted	457,538		255,158
	Restricted stock vested	(246,698	)	(182,472	)
	Restricted stock outstanding as of end of period	731,809		520,969
	The combined grant date fair value of the restricted stock issued by the Company for the year ended December 31, 2014 was $3,703 compared to $2,708 for the year ended December 31, 2013. The following table presents the amortization schedule for the Company's non-vested restricted stock remaining to be amortized into compensation expense as of December 31, 2014:
		Restricted Stock Amortization
		To Be Recognized
	Within 12 months	$	2,265
	13-24 months	1,452
	25-36 months	541
	37-48 months	36
	Total restricted stock amortization remaining	$	4,294

Income_Taxes_Notes

Income Taxes (Notes)	12 Months Ended
	Dec. 31, 2014
Income Taxes [Abstract]
Income Tax Disclosure [Text Block]	INCOME TAXES
	The Company's estimated REIT taxable income before consideration of its net operating loss carryforward was $79,229 for the year ended December 31, 2014, $71,765 for the year ended December 31, 2013, and $73,962 for the year ended December 31, 2012. After common and preferred dividend distributions during those years as well as utilization of the Company's tax net operating loss ("NOL") carryforward to offset taxable earnings, the Company does not expect to incur any income tax liability for the year ended December 31, 2014 and did not incur any material income tax liability for the years ending December 31, 2013 or December 31, 2012.
	The Company's estimated NOL carryforward as of December 31, 2014 is $120,016. Because the Company incurred an "ownership change" under Section 382 of the Internal Revenue Code ("Section 382"), the company's ability to utilize its NOL carryforward to offset its taxable income after any required dividend distributions is limited to approximately $13,451 per year with any unused amounts being accumulated and carried forward for use in subsequent years. The NOL will expire beginning in 2020 to the extent it is not used.
	After reviewing for any potentially uncertain income tax positions, the Company has concluded that it does not have any uncertain tax positions that meet the recognition or measurement criteria of ASC 740 as of December 31, 2014, December 31, 2013, or December 31, 2012, although its tax returns for those tax years are open to examination by the IRS. In the event that the Company incurs income tax related interest and penalties, its policy is to classify them as a component of provision for income taxes.

Related_Party_Transactions_Not

Related Party Transactions (Notes)	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transactions Disclosure [Text Block]	RELATED PARTY TRANSACTIONS
	The Company and DCI Commercial, Inc. ("DCI"), a former affiliate of the Company and formerly known as Dynex Commercial, Inc., were jointly named in litigation regarding the activities of DCI while it was an operating subsidiary of an affiliate of the Company. In May 2013, the Fifth Circuit Court of Appeals in Dallas, Texas (the “Fifth Circuit”) affirmed the trial court’s decision with respect to a take nothing judgment against the Company. With respect to DCI, the Fifth Circuit remanded the case to the trial court for entry of judgment and a $25.6 million damage award against DCI and for a new trial with respect to attorneys’ fees and for costs and pre- and post-judgment interest as determined by the trial court. In December 2000, the Company and DCI entered into a Litigation Cost Sharing Agreement whereby the parties set forth how the costs of defending against such litigation would be shared, and whereby the Company agreed to advance DCI's portion of the costs of defending against such litigation. The Litigation Cost Sharing Agreement remains in effect as of December 31, 2014. DCI costs advanced by the Company are loans and bear simple interest at the rate of Prime plus 8.0% per annum. As of December 31, 2014, the total amount due to the Company under the Litigation Cost Sharing Agreement, including interest, was $9,191, which has been fully reserved for collectibility by the Company. DCI is currently wholly owned by a company unaffiliated with the Company. An executive of the Company is the sole shareholder of this unaffiliated company.

Selected_Quarterly_Information

Selected Quarterly Information (Unaudited) (Notes)	12 Months Ended
	Dec. 31, 2014
Selected Quarterly Information [Abstract]
Quarterly Financial Information [Text Block]	SELECTED QUARTERLY INFORMATION (UNAUDITED)
		Year Ended December 31, 2014
		First Quarter			Second Quarter			Third Quarter			Fourth Quarter
	Operating results:
	Net interest income	$	20,007		$	21,146		$	19,942		$	18,634
	Net (loss) income to common shareholders	(3,028		)	(8,293		)	28,572			1,379
	Comprehensive income to common shareholders	26,532			26,906			14,090			6,234
	Net (loss) income per common share	$	(0.06	)	$	(0.15	)	$	0.52		$	0.03
	Cash dividends declared per common share	$	0.25		$	0.25		$	0.25		$	0.25
		Year Ended December 31, 2013
		First Quarter			Second Quarter			Third Quarter			Fourth Quarter
	Operating results:
	Net interest income	$	22,526		$	22,444		$	22,948		$	20,186
	Net income (loss) to common shareholders	18,381			29,442			(6,921		)	19,266
	Comprehensive income (loss) to common shareholders	27,427			(67,215		)	(6,184		)	19,813
	Net income (loss) per common share	$	0.34		$	0.54		$	(0.13	)	$	0.35
	Cash dividends declared per common share	$	0.29		$	0.29		$	0.27		$	0.27
	The Company used cash flow hedge accounting for the majority of its derivative instruments for the three months ended March 31, 2013 and for the three months ended June 30, 2013. Please refer to Note 1 for additional information on cash flow hedge accounting.

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS
	Management has evaluated events and circumstances occurring as of and through the date this Annual Report on Form 10-K was filed with the SEC 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 events or circumstances qualify as "nonrecognized" subsequent events as defined by ASC Topic 855:
	Subsequent to December 31, 2014, the Company granted 231,274 shares of restricted stock with a combined fair value at grant date of $1,917. The fair value of these restricted shares will be amortized into share-based compensation expense over the next 3 years.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
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 mortgage-backed securities ("MBS") 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").
Basis of Presentation [Policy Text Block]	Basis of Presentation
	The accompanying consolidated financial statements of Dynex Capital, Inc. and its qualified real estate investment trust ("REIT") subsidiaries and its taxable REIT subsidiary (together, "Dynex" or the "Company") have been prepared in accordance with the generally accepted accounting principles in the United States ("GAAP") and the instructions to the Annual Report on Form 10-K and Article 3 of Regulation S-X promulgated by the Securities and Exchange Commission (the "SEC").
Reclassifications [Policy Text Block]	Reclassifications
	Certain items in the prior periods' consolidated financial statements have been reclassified to conform to the current year’s presentation. The Company's consolidated balance sheet as of December 31, 2013 now presents its "securitized mortgage loans, net" and "other investments, net" together as "mortgage loans held for investment, net ". In addition, the Company has combined the presentation of its consolidated statements of income and its consolidated statements of other comprehensive income together as one financial statement which is now titled "consolidated statements of comprehensive income". The Company's "interest income - securitized mortgage loans" and "interest income-other investments" on its consolidated statements of income for the years ended December 31, 2013 and December 31, 2012 are now presented together as "interest income-mortgage loans held for investment, net" on its consolidated statements of comprehensive income for the years ended December 31, 2013 and December 31, 2012. The Company's "amortization and depreciation" on its consolidated statements of cash flows for the years ended December 31, 2013 and December 31, 2012 are now presented as "amortization of investment premiums, net" and "other amortization and depreciation". These presentation changes have no effect on reported total assets, total liabilities, results of operations, or cash flow activities.
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. All intercompany accounts and transactions have been eliminated in consolidation.
	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. Additional information regarding the accounting policy for the Company's securitized mortgage loans is provided below under "Mortgage Loans Held for Investment, Net ".
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, fair value measurements of its investments, other-than-temporary impairments, contingencies, and amortization of premiums and discounts. These items are discussed further below within this note to the consolidated financial statements.
Federal 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 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 gain 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 ASC Topic 740. The Company records these liabilities, if any, to the extent they are deemed more likely than not to have been incurred.
Cash and Cash Equivalents, Policy [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.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	Restricted Cash
	Restricted cash consists of cash the Company has pledged to cover initial and variation margin with its counterparties.
Mortgage Backed Securities [Policy Text Block]	Mortgage-Backed Securities
	In accordance with ASC Topic 320, the Company has designated its investments in MBS as available-for-sale ("AFS"). All of the Company’s MBS are recorded at fair value on the consolidated balance sheet. Changes in fair value for the Company's AFS securities are reported in other comprehensive income ("OCI") until each security is collected, disposed of, or 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 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 Agency MBS as well as any non-Agency MBS rated 'AA' and higher at the time of purchase are amortized into interest income over the expected life of such securities using the effective yield method and adjustments to premium amortization are made for actual cash payments as well as changes in projected future cash payments in accordance with ASC Topic 310-20. The Company's projections of future cash payments are based on input and analysis received from external sources and internal models, and includes assumptions about the amount and timing of credit losses, loan prepayment rates, fluctuations in interest rates, 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 holds non-Agency MBS that were rated less than 'AA' at the time of purchase by at least one national rating agency. These non-Agency MBS were purchased at discounts to their par value, which management does not believe to be substantial. The Company accretes the discount into income over the security's expected life, which reflects management's estimate of the security's projected cash flows in accordance with ASC Topic 325-40. 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 8 for further discussion of MBS fair value measurements.
	Other-than-Temporary Impairment. 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 3 for additional information related to the Company's evaluation for OTTI.
Mortgage Loans Held for Investment, Net [Policy Text Block]	Mortgage Loans Held for Investment, Net
	The Company originated or purchased mortgage loans from 1992 through 1998, and these mortgage loans are reported at amortized cost in accordance with ASC Topic 310-10. A portion of these loans is pledged as collateral to support the repayment of one remaining class of a securitization financing bond issued by the Company in 2002. The associated securitization financing bond is treated as debt of the Company and is presented as "non-recourse collateralized financing" on the consolidated balance sheet. Securitized mortgage loans can only be sold subject to the lien of the respective securitization financing indenture. An allowance has been established for currently existing and probable losses on the Company's mortgage loans held for investment.
Investment in Limited Partnership [Policy Text Block]	Investment in Limited Partnership
	The Company is a limited partner with a less than 50% interest in a limited partnership for which it does not have substantive participating or kick-out rights that overcome the general partner's presumption of control. The Company accounts for its investment in this limited partnership using the equity method of accounting, which requires initially recording an investment in the equity of an investee at cost and subsequently adjusting the carrying amount of the investment to recognize the investor's share of the earnings or losses, capital contributions and distributions, and other changes in equity.
Repurchase Agreements [Policy Text Block]	Repurchase Agreements
	Repurchase agreements 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, which currently include interest rate swaps and Eurodollar futures, are accounted for in accordance with ASC Topic 815, which requires an entity to recognize all derivatives as either assets or liabilities in the balance sheet and to measure those instruments at fair value. All periodic interest costs and other changes in fair value, including gains and losses recognized upon termination, associated with derivative instruments are recorded in "gain (loss) on derivative instruments, net" on the Company's consolidated statement of comprehensive income.
	Effective June 30, 2013, the Company discontinued cash flow hedge accounting for derivative instruments which had previously been accounted for as cash flow hedges under ASC Topic 815. Activity up to and including June 30, 2013 for those agreements previously designated as cash flow hedges was recorded in accordance with cash flow hedge accounting as prescribed by ASC Topic 815, which states that the effective portion of the hedge relationship on an instrument designated as a cash flow hedge is reported in the current period's other comprehensive income while the ineffective portion is immediately reported as a component of the current period’s net income. The balance remaining in AOCI related to the de-designated cash flow hedges is amortized into the Company's net income as a portion of "interest expense" over the remaining life of the interest rate swap agreements. Subsequent to June 30, 2013, changes in the fair value of the Company's derivative instruments, plus periodic settlements, are recorded in the Company's net income as a portion of "gain (loss) on derivative instruments, net".
	Although MBS have characteristics that meet the definition of a derivative instrument, ASC Topic 815 specifically excludes these instruments from its scope because they are accounted for as debt securities under ASC Topic 320.
Stock-based Compensation [Policy Text Block]	Share-Based Compensation
	Pursuant to the Company’s 2009 Stock and Incentive Plan ("SIP"), 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 share-based based 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.
Contingencies [Policy Text Block]	Contingencies
	In the normal course of business, there are 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 in accordance with ASC Topic 450, which states that a liability is recognized 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. As of December 31, 2014, the Company does not have any contingencies for which it believes a probable loss has been incurred.
Recent Accounting Pronouncements [Text Block]	Recent Accounting Pronouncements
	In June 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2014-11, Transfers and Servicing (Topic 860): Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures, which changes the accounting for repurchase-to-maturity transactions and repurchase financing arrangements. The guidance eliminates sale accounting for repurchase-to-maturity transactions and supersedes the guidance under which a transfer of a financial asset and a contemporaneous repurchase financing could be accounted for on a combined basis as a forward agreement, which has resulted in outcomes referred to as off-balance-sheet accounting. All of the Company's repurchase agreement transactions are accounted for as secured borrowings; therefore the accounting changes required by ASU No. 2014-11 do not impact the Company's consolidated financial statements. ASU No. 2014-11 also requires two additional disclosures about repurchase agreements and other similar transactions. The first disclosure requires an entity to disclose information on transfers accounted for as sales in transactions that are economically similar to repurchase agreements. The Company does not account for any of its repurchase agreement transactions as sales; therefore this new disclosure does not impact the Company's current disclosures. The second disclosure requires the following disclosures for repurchase agreements, securities lending transactions, and repurchase-to-maturity transactions that are accounted for as secured borrowings: a disaggregation of the gross obligation by the class of collateral pledged; the remaining contractual tenor of the agreements; and a discussion of the potential risks associated with the agreements and the related collateral pledged, including obligations arising from a decline in the fair value of the collateral pledged and how those risks are managed. The Company already provides these disclosures in its "Notes to the Consolidated Financial Statements" and within "Liquidity and Capital Resources" in Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" of this Annual Report on Form 10-K. The amendments provided in ASU No. 2014-11 are effective for public business entities for the first interim or annual period beginning after December 15, 2014. ASU No. 2014-11 will not have a material impact on the Company's consolidated financial statements.
	In addition, the FASB issued ASU No. 2014-12, Compensation - Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. The amendments in this ASU are effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. The Company has not issued and does not anticipate issuing any share-based payments with terms that require a performance-based target; therefore this ASU will not have an impact on the Company's consolidated financial statements.
	The FASB issued ASU No. 2014-13, Consolidation (Topic 810): Measuring the Financial Assets and the Financial Liabilities of a Consolidated Collateralized Financing Entity, which provides an alternative to Topic 820, Fair Value Measurement, for measuring the financial assets and the financial liabilities of a consolidated collateralized financing entity to eliminate the difference in the fair value of the financial assets of a collateralized financing entity, as determined under GAAP, when they differ from the fair value of its financial liabilities even when the financial liabilities have recourse only to the financial assets. When the measurement alternative is elected, both the financial assets and the financial liabilities of the collateralized financing entity should be measured using the more observable of the fair value of the financial assets or the fair value of the financial liabilities. The amendments clarify that when the measurement alternative is elected, a reporting entity's consolidated net income (loss) should reflect the reporting entity's own economic interests in the collateralized financing entity, including; (1) changes in the fair value of the beneficial interests retained by the reporting entity, and (2) beneficial interests that represent compensation for services. The measurement alternative provided in ASU No. 2014-13 may be applied using a modified retrospective approach by recording a cumulative-effect adjustment to equity as of the beginning of the annual period of adoption. The amendments may also be applied retrospectively to all relevant prior periods beginning with the annual period in which ASU No. 2009-17 was initially adopted. ASU No. 2014-13 is effective for public entities for annual periods, and interim periods within those annual periods, beginning after December 15, 2015, and early adoption is permitted as of the beginning of an annual period. Management has evaluated ASU No. 2014-13 and has determined that if the Company elects to adopt this measurement alternative in the future for its currently existing consolidated collateralized financing entity, it will not have a material impact on the Company's consolidated financial statements.
	The FASB issued ASU No. 2014-15, Presentation of Financial Statements-Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern, which provides guidance about management's responsibility under GAAP to evaluate whether there is substantial doubt about an organization's ability to continue as a going concern and to provide related footnote disclosures. Specifically, the ASU (1) provides a definition of the term "substantial doubt", (2) requires an evaluation by management every reporting period including interim periods, (3) provides principles for considering the mitigating effect of management's plans, (4) requires certain disclosures when substantial doubt exists regardless of the success of any mitigating plans or actions, (5) requires an express statement and other disclosures when substantial doubt is not alleviated, and (6) requires an assessment for a period of one year after the date that the financial statements are issued. The amendments in this ASU are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. Management intends to comply with the requirements set forth in ASU No. 2014-15.

Net_Income_Per_Common_Share_Ta

Net Income Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share, Basic and Diluted [Abstract]
Schedule of Calculation of Numerator and Denominator in Net Income Per Common Share [Table Text Block]	The following table presents the calculation of the numerator and denominator for both basic and diluted net income per common share for the periods indicated:
		Year Ended
		December 31, 2014					December 31, 2013					31-Dec-12
		Net			Weighted-Average Common Shares		Net			Weighted-		Net			Weighted-
		Income					Income			Average		Income			Average
										Common					Common
										Shares					Shares
	Net income	$	27,806				$	68,069				$	74,042
	Preferred stock dividends	(9,176		)			(7,902		)			(2,036		)
	Net income to common shareholders	18,630			54,701,485		60,167			54,647,643		72,006			53,146,416
	Effect of dilutive instruments	—			—		—			—		—			—
	Diluted net income to common shareholders	$	18,630		54,701,485		$	60,167		54,647,643		$	72,006		53,146,416
	Net income per common share:
	Basic and diluted (1)				$	0.34				$	1.1				$	1.35
	-1	For the year ended December 31, 2012, the calculation of diluted net income per common share excludes the effect of 15,000 unexercised stock option awards because their inclusion would have been anti-dilutive. The Company did not have any potentially dilutive securities outstanding for the years ended December 31, 2014 or December 31, 2013.

Mortgage_Backed_Securities_Mor1

Mortgage Backed Securities Mortgage backed securities (Tables)	12 Months Ended
	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Schedule of Realized Gain (Loss) [Table Text Block]	The Company received proceeds of $503,918, $357,892, and $125,108 for the sale of MBS during the years ended December 31, 2014, December 31, 2013, and December 31, 2012, respectively. The following table presents the gross realized gains (losses) of those sales included in "gain on sale of investments, net" on the Company's consolidated statements of comprehensive income for the periods indicated:
		Year Ended
		December 31,
		2014			2013			2012 (1)
	($ in thousands)	Gain (Loss) Recognized			Gain (Loss) Recognized			Gain (Loss) Recognized
	Gross realized gains on sales of MBS	$	22,492		$	8,670		$	5,319
	Gross realized losses on sales of MBS	(6,269		)	(5,316		)	—
	Total included in gain on sale of investments, net	$	16,223		$	3,354		$	5,319
	-1	Total gain on sale of investments, net for the year ended December 31, 2012 includes $2,072 and $1,070 of gains recognized from the Company's liquidation of a securitized mortgage loan and an investment in Freddie Mac Unsecured Senior Notes, respectively, which are not included in this table.
Available-for-sale Securities [Table Text Block]	The following tables provide detail by type of investment for the Company’s MBS designated as AFS for the periods indicated:
		December 31, 2014
		Par			Net Premium (Discount)			Amortized Cost				Gross Unrealized Gain				Gross Unrealized Loss			Fair Value		WAC (1)
	RMBS:
	Agency	$	2,086,807		$	113,635		$	2,200,442			$	8,473			$	(22,215	)	$	2,186,700	3.09	%
	Non-Agency	22,432			(17		)	22,415				107				(74		)	22,448		3.83	%
		2,109,239			113,618			2,222,857				8,580				(22,289		)	2,209,148
	CMBS:
	Agency	301,943			18,042			319,985				15,288				(76		)	335,197		5.21	%
	Non-Agency	210,358			(8,520		)	201,838				6,679				(479		)	208,038		4.33	%
		512,301			9,522			521,823				21,967				(555		)	543,235
	CMBS IO (2):
	Agency	—			426,564			426,564				12,252				(79		)	438,737		0.8	%
	Non-Agency	—			319,280			319,280				6,069				(230		)	325,119		0.72	%
		—			745,844			745,844				18,321				(309		)	763,856
	Total AFS securities:	$	2,621,540		$	868,984		$	3,490,524			$	48,868			$	(23,153	)	$	3,516,239
	-1	The current weighted average coupon ("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 Agency CMBS IO and non-Agency CMBS IO was $10,460,113 and $7,868,896, respectively, as of December 31, 2014.
		31-Dec-13
		Par			Net Premium (Discount)			Amortized Cost				Gross Unrealized Gain				Gross Unrealized Loss			Fair Value		WAC (1)
	RMBS:
	Agency	$	2,591,568		$	154,220		$	2,745,788			$	6,104			$	(59,742	)	$	2,692,150	3.22	%
	Non-Agency	13,845			(338		)	13,507				338				(80		)	13,765		4.61	%
		2,605,413			153,882			2,759,295				6,442				(59,822		)	2,705,915
	CMBS:
	Agency (2)	273,830			19,061			292,891				10,793				(900		)	302,784		5.07	%
	Non-Agency	375,703			(18,277		)	357,426				15,366				(3,511		)	369,281		5.1	%
		649,533			784			650,317				26,159				(4,411		)	672,065
	CMBS IO (3):
	Agency	—			453,766			453,766				9,895				(3,334		)	460,327		0.83	%
	Non-Agency	—			150,518			150,518				2,618				(1,999		)	151,137		0.66	%
		—			604,284			604,284				12,513				(5,333		)	611,464
	Total AFS securities:	$	3,254,946		$	758,950		$	4,013,896			$	45,114			$	(69,566	)	$	3,989,444
	-1	The current weighted average coupon ("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	As of December 31, 2013, the Company had Agency CMBS with an amortized cost of $26,920 and fair value of $28,717 which were designated as trading securities and are not included in this table. The Company changed the designation of these Agency CMBS to AFS during the three months ended June 30, 2014. Changes in the fair value of these MBS while they were designated as trading were recognized in net income within "fair value adjustments, net". Changes in the fair value of these MBS, which are now designated as AFS, are recognized in "other comprehensive income". As of December 31, 2014, the Company does not have any MBS designated as trading.
	-3	The notional balance for the Agency CMBS IO and non-Agency CMBS IO was $10,160,502 and $4,274,957, respectively, as of December 31, 2013.
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block]	The following table presents certain information for those Agency MBS in an unrealized loss position as of December 31, 2014 and December 31, 2013:
		31-Dec-14								31-Dec-13
		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	$	322,741		$	(879	)	24		$	1,912,937			$	(43,543	)		150
	Non-Agency MBS	111,778			(625		)	24		162,558				(5,435		)		39
	Continuous unrealized loss position for 12 months or longer:
	Agency MBS	$	1,321,323		$	(21,491	)	113		$	670,402			$	(20,433	)		67
	Non-Agency MBS	18,037			(159		)	5		6,310				(155		)		6

Mortgage_Loans_Held_for_Invest1

Mortgage Loans Held for Investment, Net and Related Financing (Tables)	12 Months Ended
	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans Held for Investment, Net [Table Text Block]	The Company's mortgage loans held for investment, net consist of securitized and unsecuritized mortgage loans originated or purchased by the Company from 1992 through 1998. The following table provides detail by type of collateral as of the periods indicated:
		31-Dec-14			31-Dec-13
	Single-family mortgage loans held for investment, amortized cost	$	30,214		$	35,328
	Commercial mortgage loans held for investment, amortized cost	9,736			20,352
	Allowance for loan losses	(250		)	(257		)
	Total mortgage loans held for investment, net	$	39,700		$	55,423

Repurchase_Agreements_Repurcha

Repurchase Agreements Repurchase Agreements (Tables)	12 Months Ended
	Dec. 31, 2014
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Schedule of Assets and Associated Liabilities Accounted for as Secured Borrowings [Table Text Block]	The following tables present the components of the Company’s repurchase agreements as of December 31, 2014 and December 31, 2013 by the fair value and type of securities pledged as collateral:
		December 31, 2014
	Collateral Type	Balance			Weighted			Fair Value of
					Average Rate			Collateral Pledged
	Agency RMBS	$	1,977,338		0.39	%		2,064,704
	Non-Agency RMBS	17,594			1.57	%		21,787
	Agency CMBS	253,857			0.36	%		291,103
	Non-Agency CMBS	114,895			1.15	%		140,216
	Agency CMBS IOs	372,609			0.92	%		430,638
	Non-Agency CMBS IO	266,983			1.04	%		315,149
	Securitization financing bonds	9,834			1.51	%		11,000
		$	3,013,110		0.55	%		$	3,274,597
		December 31, 2013
	Collateral Type	Balance			Weighted			Fair Value of Collateral Pledged
					Average Rate
	Agency RMBS	$	2,522,503		0.42	%		2,598,158
	Non-Agency RMBS	10,569			1.8	%		12,746
	Agency CMBS	246,849			0.39	%		306,318
	Non-Agency CMBS	303,674			1.27	%		367,859
	Agency CMBS IOs	369,948			1.16	%		449,072
	Non-Agency CMBS IOs	106,803			1.27	%		136,227
	Securitization financing bonds	20,651			1.59	%		19,686
	Deferred costs	(243		)	n/a			n/a
		$	3,580,754		0.61	%		$	3,890,066
	The combined weighted average original term to maturity for the Company’s repurchase agreements was 144 days as of December 31, 2014 compared to 114 days as of December 31, 2013. The following table provides a summary of the original maturities as of December 31, 2014 and December 31, 2013:
	Original Maturity	December 31,			December 31,
		2014			2013
	Less than 30 days	$	250,635		$	4,736
	30 to 90 days	617,399			1,176,631
	91 to 180 days	904,830			1,439,225
	181 to 364 days	1,030,569			960,405
	1 year or longer	209,677			—
	Deferred costs	—			(243		)
		$	3,013,110		$	3,580,754

Derivatives_Tables

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	The table below summarizes information about the Company’s derivative instruments treated as trading instruments on its consolidated balance sheet as of the dates indicated:
			December 31, 2014
			Derivative Assets								Derivative Liabilities
	Trading Instruments		Fair Value				Notional				Fair Value				Notional
	Interest rate swaps		$	5,727			$	440,000			$	(3,002	)		$	485,000
	Eurodollar futures (1)		—				—				(32,896		)		16,600,000
	Total		$	5,727			$	440,000			$	(35,898	)		$	17,085,000
			December 31, 2013
			Derivative Assets								Derivative Liabilities
	Trading Instruments		Fair Value				Notional				Fair Value				Notional
	Interest rate swaps		$	18,488			$	575,000			$	(1,336	)		$	215,000
	Eurodollar futures (1)		—				—				(5,345		)		9,000,000
	Total		$	18,488			$	575,000			$	(6,681	)		$	9,215,000
	-1	The Eurodollar futures aggregate notional amount represents the total notional of the 3-month contracts with expiration dates from 2015 to 2020. The maximum notional outstanding for any future 3-month period did not exceed $1,300,000 as of December 31, 2014 and $1,175,000 as of December 31, 2013.
Schedule of Derivative Instruments [Table Text Block]	The following table summarizes the contractual maturities remaining for the Company’s outstanding interest rate swap agreements as of December 31, 2014:
	Remaining Maturity		Pay-Fixed Interest Rate Swaps				Pay-Fixed			Receive Fixed Interest Rate Swaps				Receive-Fixed
							Weighted-Average Rate(1)							Weighted-Average Rate
	37-48 months		$	185,000			0.92	%		$	—			—	%
	49-60 months		235,000				1.45	%		250,000				1.91	%
	61-72 months		25,000				1.61	%		—				—	%
	73-84 months		25,000				2.19	%		—				—	%
	85-96 months		—				—	%		—				—	%
	97-108 months		30,000				1.93	%		—				—	%
	109-120 months		150,000				2.17	%		25,000				2.71	%
Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]	The following table summarizes the volume of activity related to derivative instruments for the periods indicated:
	For the year ended December 31, 2014:	Beginning of Period Notional Amount				Additions				Settlement, Termination, Expiration or Exercise				End of Period Notional Amount
	Receive-fixed interest rate swaps	$	—			$	275,000			$	—			$	275,000
	Pay-fixed interest rate swaps	790,000				75,000				(215,000		)		650,000
	Eurodollar futures	9,000,000				7,600,000				—				16,600,000
		$	9,790,000			$	7,950,000			$	(215,000	)		$	17,525,000
Schedule of Derivative Instruments Included in Trading Activities [Table Text Block]	The table below provides detail of the Company's "gain (loss) on derivative instruments, net" by type of interest rate derivative for the periods indicated:
			Year Ended
			December 31,
	Type of Derivative Instrument		2014				2013				2012
	Receive-fixed interest rate swaps		$	4,912			$	—			$	—
	Pay-fixed interest rate swaps		(30,754		)		9,315				(908		)
	Eurodollar futures		(27,551		)		(19,391		)		—
	Gain (loss) on derivative instruments, net		$	(53,393	)		$	(10,076	)		$	(908	)
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	The table below describes the components of the reclassification adjustments out of AOCI related to certain interest rate swaps that were formerly designated as cash flow hedges and recognized as a portion of "interest expense" on the Company statements of comprehensive income for the periods indicated:
		Year Ended
		December 31,
		2014				2013				2012
	Reclassification adjustment due to amortization of de-designated cash flow hedges	$	6,788			$	5,193			$	—
	Reclassification adjustment due to recognition of interest expense from cash flow hedges	—				8,796				14,448
	Total reclassification adjustment related to cash flow hedges	$	6,788			$	13,989			$	14,448

Offsetting_Assets_and_Liabilit

Offsetting Assets and Liabilities Offsetting Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Offsetting Assets [Line Items]
Offsetting Assets [Table Text Block]
		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						Net Amount
								Financial Instruments Received as Collateral			Cash Received as Collateral
	31-Dec-14
	Derivative assets	$	5,727	$	—	$	5,727	$	(1,073	)	$	(4,521	)	$	133
	December 31, 2013:
	Derivative assets	$	18,488	$	—	$	18,488	$	(193	)	$	(12,141	)	$	6,154

Offsetting_Assets_and_Liabilit1

Offsetting Assets and Liabilities Offsetting Liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Offsetting Liabilities [Line Items]
Offsetting Liabilities [Table Text Block]
		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						Net Amount
								Financial Instruments Posted as Collateral			Cash Posted as Collateral
	31-Dec-14
	Derivative liabilities	$	35,898	$	—	$	35,898	$	(2,494	)	$	(32,994	)	$	410
	Repurchase agreements	3,013,110		—		3,013,110		(3,013,110		)	—			—
		$	3,049,008	$	—	$	3,049,008	$	(3,015,604	)	$	(32,994	)	$	410
	December 31, 2013:
	Derivative liabilities	$	6,681	$	—	$	6,681	$	(1,299	)	$	(5,382	)	$	—
	Repurchase agreements	3,580,754		—		3,580,754		(3,580,754		)	—			—
		$	3,587,435	$	—	$	3,587,435	$	(3,582,053	)	$	(5,382	)	$	—

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The following table presents the fair value of the Company’s assets and liabilities presented on its consolidated balance sheets, 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:
		December 31, 2014
		Fair Value				Level 1 - Unadjusted Quoted Prices in Active Markets			Level 2 - Observable Inputs			Level 3 - Unobservable Inputs
	Assets:
	Mortgage-backed securities	$	3,516,239			$	—		$	3,472,282		$	43,957
	Derivative assets	5,727				—			5,727			—
	Total assets carried at fair value	$	3,521,966			$	—		$	3,478,009		$	43,957
	Liabilities:
	Derivative liabilities	$	35,898			$	32,896		$	3,002		$	—
	Total liabilities carried at fair value	$	35,898			$	32,896		$	3,002		$	—
		December 31, 2013
		Fair Value				Level 1 - Unadjusted Quoted Prices in Active Markets			Level 2 - Observable Inputs			Level 3 - Unobservable Inputs
	Assets:
	Mortgage-backed securities	$	4,018,161			$	—		$	3,944,681		$	73,480
	Derivative assets	18,488				—			18,488			—
	Total assets carried at fair value	$	4,036,649			$	—		$	3,963,169		$	73,480
	Liabilities:
	Derivative liabilities	$	6,681			$	5,345		$	1,336		$	—
	Total liabilities carried at fair value	$	6,681			$	5,345		$	1,336		$	—
Fair Value Inputs, Assets, Quantitative Information [Table Text Block]	The table below presents information about the significant unobservable inputs used in the fair value measurement for the Company's Level 3 non-Agency CMBS and RMBS as of December 31, 2014:
		Quantitative Information about Level 3 Fair Value Measurements (1)
		Prepayment Speed		Default Rate			Severity		Discount Rate
	Non-Agency CMBS	20 CPY		2	%		35	%	9.9	%
	Non-Agency RMBS	10 CPR		1	%		20	%	6.5	%
	-1	Data presented are weighted averages.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	The following table presents the activity of the instruments fair valued at Level 3 on a recurring basis during the periods indicated:
		Level 3 Fair Value
		Non-Agency CMBS				Non-Agency RMBS			Other			Total assets
	Balance as of January 1, 2013	$	100,102			$	5,118		$	25		$	105,245
	Purchases	26,021				—			—			26,021
	Sales/write-offs to net income	—				—			(25		)	(25		)
	Unrealized (loss) gain included in OCI	(6,026		)		5			—			(6,021		)
	Principal payments	(49,167		)		(2,421		)	—			(51,588		)
	(Amortization) accretion	(197		)		45			—			(152		)
	Balance as of December 31, 2013	70,733				2,747			—			73,480
	Unrealized gain (loss) included in OCI	2,317				(139		)	—			2,178
	Principal payments	(31,253		)		(1,014		)	—			(32,267		)
	Accretion	236				330			—			566
	Balance as of end of December 31, 2014	$	42,033			$	1,924		$	—		$	43,957
Recorded basis and fair value [Table Text Block]	The following table presents a summary of the recorded basis and estimated fair values of the Company’s financial instruments as of the dates indicated:
		December 31, 2014							December 31, 2013
		Recorded Basis				Fair Value			Recorded Basis			Fair Value
	Assets:
	Mortgage-backed securities	$	3,516,239			$	3,516,239		$	4,018,161		$	4,018,161
	Mortgage loans held for investment, net(1)	39,700				35,024			55,423			46,383
	Derivative assets	5,727				5,727			18,488			18,488
	Liabilities:
	Repurchase agreements (2)	$	3,013,110			$	3,013,110		$	3,580,754		$	3,580,997
	Non-recourse collateralized financing (1)	10,786				10,366			12,914			12,414
	Derivative liabilities	35,898				35,898			6,681			6,681

Shareholders_Equity_Tables

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Preferred Stock [Text Block]	The Company has 2,300,000 shares of its 8.50% Series A Cumulative Redeemable Preferred Stock and 2,250,000 shares of its 7.625% Series B Cumulative Redeemable Preferred Stock issued and outstanding as of December 31, 2014 (collectively, the "Preferred Stock"). 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. Except under certain limited circumstances intended to preserve the Company's REIT status, upon the occurrence of a change in control as defined in Article IIIA, Section 7(d) of the Company’s Articles of Incorporation, or to avoid the direct or indirect imposition of a penalty tax in respect of, or to protect the tax status of, any of the Company’s real estate mortgage investment conduits (“REMIC”) interests or a REMIC in which the Company may acquire an interest (as permitted by the Company’s Articles of Incorporation), the Company may not redeem the Series A Preferred Stock prior to July 31, 2017 or the Series B Preferred Stock prior to April 30, 2018. On or after these dates, at any time and from time to time, the Preferred Stock may be redeemed in whole, or in part, at the Company's option at a cash redemption price of $25.00 per share plus any accumulated and unpaid dividends. 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. 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.
Schedule of Common Stock Outstanding Roll Forward [Table Text Block]	The following table presents a summary of the changes in the number of common shares outstanding for the periods presented:
		Year Ended
		December 31,
		2014		2013
	Balance as of beginning of period	54,310,484		54,268,915
	Common stock issued under DRIP	16,753		515,257
	Common stock issued under ATM program	—		180,986
	Common stock issued or redeemed under stock and incentive plans	471,210		270,158
	Common stock forfeited for tax withholding on share-based compensation	(59,336	)	(52,385	)
	Common stock repurchased during the period	—		(872,447	)
	Balance as of end of period	54,739,111		54,310,484
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]	The following table presents a rollforward of the restricted stock activity for the periods indicated:
		Year Ended
		December 31,
		2014		2013
	Restricted stock outstanding as of beginning of period	520,969		448,283
	Restricted stock granted	457,538		255,158
	Restricted stock vested	(246,698	)	(182,472	)
	Restricted stock outstanding as of end of period	731,809		520,969
Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block]	The following table presents the amortization schedule for the Company's non-vested restricted stock remaining to be amortized into compensation expense as of December 31, 2014:
		Restricted Stock Amortization
		To Be Recognized
	Within 12 months	$	2,265
	13-24 months	1,452
	25-36 months	541
	37-48 months	36
	Total restricted stock amortization remaining	$	4,294

Net_Income_Per_Common_Share_De

Net Income Per Common Share (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount											15,000
Net income (loss)									$27,806	$68,069	$74,042
Preferred Stock Dividends									-9,176	-7,902	-2,036
Net income to common shareholders	1,379	28,572	-3,028	19,266	-6,921	29,442	18,381	-8,293	18,630	60,167	72,006
Weighted average common shares - basic and diluted									54,701,485	54,647,643	53,146,416
Effect of dilutive instruments on net income									0	0	0
Diluted net income to common shareholders									$18,630	$60,167	$72,006
Effect of dilutive instruments on weighted average common shares									0	0	0
Diluted, Weighted Average Number Common Shares									54,701,485	54,647,643	53,146,416
Net income per common share - basic and diluted	$0.03	$0.52	($0.06)	$0.35	($0.13)	$0.54	$0.34	($0.15)	$0.34	$1.10	$1.35

Mortgage_Backed_Securities_Mor2

Mortgage Backed Securities Mortgage backed securities designated as AFS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	$2,621,540,000		$3,254,946,000
Available-for-sale MBS, Unamortized Premium (Discount)	868,984,000		758,950,000
Available-for-sale MBS, Amortized Cost	3,490,524,000		4,013,896,000
Available-for-sale Debt Securities, Gross Unrealized Gain	48,868,000		45,114,000
Available-for-sale MBS, Gross Unrealized Loss	-23,153,000		-69,566,000
Available-for-sale MBS, Fair Value	3,516,239,000		3,989,444,000
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	503,918,000		357,892,000		125,108,000
Available-for-sale Securities, Gross Realized Gains	22,492,000		8,670,000		5,319,000
Available-for-sale Securities, Gross Realized Losses	-6,269,000		-5,316,000		0
Available-for-sale Securities, Gross Realized Gain (Loss)	16,223,000		3,354,000		5,319,000	[1]
Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	2,109,239,000		2,605,413,000
Available-for-sale MBS, Unamortized Premium (Discount)	113,618,000		153,882,000
Available-for-sale MBS, Amortized Cost	2,222,857,000		2,759,295,000
Available-for-sale Debt Securities, Gross Unrealized Gain	8,580,000		6,442,000
Available-for-sale MBS, Gross Unrealized Loss	-22,289,000		-59,822,000
Available-for-sale MBS, Fair Value	2,209,148,000		2,705,915,000
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	512,301,000		649,533,000
Available-for-sale MBS, Unamortized Premium (Discount)	9,522,000		784,000
Available-for-sale MBS, Amortized Cost	521,823,000		650,317,000
Available-for-sale Debt Securities, Gross Unrealized Gain	21,967,000		26,159,000
Available-for-sale MBS, Gross Unrealized Loss	-555,000		-4,411,000
Available-for-sale MBS, Fair Value	543,235,000		672,065,000
CMBS IO [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	0		0
Available-for-sale MBS, Unamortized Premium (Discount)	745,844,000		604,284,000
Available-for-sale MBS, Amortized Cost	745,844,000		604,284,000
Available-for-sale Debt Securities, Gross Unrealized Gain	18,321,000		12,513,000
Available-for-sale MBS, Gross Unrealized Loss	-309,000		-5,333,000
Available-for-sale MBS, Fair Value	763,856,000		611,464,000
Agency MBS [Member] | Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	2,086,807,000		2,591,568,000
Available-for-sale MBS, Unamortized Premium (Discount)	113,635,000		154,220,000
Available-for-sale MBS, Amortized Cost	2,200,442,000		2,745,788,000
Available-for-sale Debt Securities, Gross Unrealized Gain	8,473,000		6,104,000
Available-for-sale MBS, Gross Unrealized Loss	-22,215,000		-59,742,000
Available-for-sale MBS, Fair Value	2,186,700,000		2,692,150,000
Available-for-sale MBS, Weighted Average Coupon	3.09%	[2]	3.22%	[3]
Agency MBS [Member] | Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	301,943,000		273,830,000
Available-for-sale MBS, Unamortized Premium (Discount)	18,042,000		19,061,000
Available-for-sale MBS, Amortized Cost	319,985,000		292,891,000	[4]
Available-for-sale Debt Securities, Gross Unrealized Gain	15,288,000		10,793,000
Available-for-sale MBS, Gross Unrealized Loss	-76,000		-900,000
Available-for-sale MBS, Fair Value	335,197,000		302,784,000	[4]
Available-for-sale MBS, Weighted Average Coupon	5.21%	[2]	5.07%	[3]
Agency MBS [Member] | CMBS IO [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	0	[5]	0	[6]
Available-for-sale MBS, Unamortized Premium (Discount)	426,564,000		453,766,000
Available-for-sale MBS, Amortized Cost	426,564,000		453,766,000
Available-for-sale Debt Securities, Gross Unrealized Gain	12,252,000		9,895,000
Available-for-sale MBS, Gross Unrealized Loss	-79,000		-3,334,000
Available-for-sale MBS, Fair Value	438,737,000		460,327,000
Available-for-sale MBS, Weighted Average Coupon	0.80%	[2]	0.83%	[3]
Notional balance for interest only securities	10,460,113,000		10,160,502,000
Non-Agency MBS [Member] | Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	22,432,000		13,845,000
Available-for-sale MBS, Unamortized Premium (Discount)	-17,000		-338,000
Available-for-sale MBS, Amortized Cost	22,415,000		13,507,000
Available-for-sale Debt Securities, Gross Unrealized Gain	107,000		338,000
Available-for-sale MBS, Gross Unrealized Loss	-74,000		-80,000
Available-for-sale MBS, Fair Value	22,448,000		13,765,000
Available-for-sale MBS, Weighted Average Coupon	3.83%	[2]	4.61%	[3]
Non-Agency MBS [Member] | Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	210,358,000		375,703,000
Available-for-sale MBS, Unamortized Premium (Discount)	-8,520,000		-18,277,000
Available-for-sale MBS, Amortized Cost	201,838,000		357,426,000
Available-for-sale Debt Securities, Gross Unrealized Gain	6,679,000		15,366,000
Available-for-sale MBS, Gross Unrealized Loss	-479,000		-3,511,000
Available-for-sale MBS, Fair Value	208,038,000		369,281,000
Available-for-sale MBS, Weighted Average Coupon	4.33%	[2]	5.10%	[3]
Non-Agency MBS [Member] | CMBS IO [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Par Balance	0	[5]
Available-for-sale MBS, Unamortized Premium (Discount)	319,280,000		150,518,000
Available-for-sale MBS, Amortized Cost	319,280,000		150,518,000
Available-for-sale Debt Securities, Gross Unrealized Gain	6,069,000		2,618,000
Available-for-sale MBS, Gross Unrealized Loss	-230,000		-1,999,000
Available-for-sale MBS, Fair Value	325,119,000		151,137,000
Available-for-sale MBS, Weighted Average Coupon	0.72%	[2]	0.66%	[3]
Notional balance for interest only securities	7,868,896,000		4,274,957,000
Agency MBS [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	322,741,000		1,912,937,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	879,000		43,543,000
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for Less than One Year	24		150
Available-for-sale MBS, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	1,321,323,000		670,402,000
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	21,491,000		20,433,000
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for Greater than or Equal to One Year	113		67
Non-Agency MBS [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale MBS, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	111,778,000		162,558,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	625,000		5,435,000
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for Less than One Year	24		39
Available-for-sale MBS, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	18,037,000		6,310,000
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$159,000		$155,000
Available-for-sale MBS, Number of Securities in Continuous Unrealized Loss Position for Greater than or Equal to One Year	5		6
[1]	(1) Total gain on sale of investments, net for the year ended December 31, 2012 includes $2,072 and $1,070 of gains recognized from the Company's liquidation of a securitized mortgage loan and an investment in Freddie Mac Unsecured Senior Notes, respectively, which are not included in this table.
[2]	(1) The current weighted average coupon ("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).
[3]	(1)The current weighted average coupon ("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).
[4]	(2) As of December 31, 2013, the Company had Agency CMBS with an amortized cost of $26,920 and fair value of $28,717 which were designated as trading securities and are not included in this table. The Company changed the designation of these Agency CMBS to AFS during the three months ended June 30, 2014. Changes in the fair value of these MBS while they were designated as trading were recognized in net income within "fair value adjustments, net". Changes in the fair value of these MBS, which are now designated as AFS, are recognized in "other comprehensive income". As of December 31, 2014, the Company does not have any MBS designated as trading.
[5]	(2)The notional balance for Agency CMBS IO and non-Agency CMBS IO was $10,460,113 and $7,868,896, respectively, as of December 31, 2014.
[6]	(3) The notional balance for the Agency CMBS IO and non-Agency CMBS IO was $10,160,502 and $4,274,957, respectively, as of December 31, 2013.

Mortgage_Backed_Securities_Mor3

Mortgage Backed Securities Mortgage backed securities designated as Trading (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Trading Securities and Other Trading Assets [Line Items]
MBS designated as trading, amortized cost	$26,920
MBS designated as trading, fair value	$28,717

Mortgage_Loans_Held_for_Invest2

Mortgage Loans Held for Investment, Net and Related Financing (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Mortgage Loans Held for Investment, Net [Abstract]
Loans and Leases Receivable, Gross, Carrying Amount, Consumer	$30,214,000	$35,328,000
Loans Receivable, Gross, Commercial, Real Estate	9,736,000	20,352,000
Allowance for Loan and Lease Losses, Real Estate	250,000	257,000
Mortgage Loans on Real Estate, Commercial and Consumer, Net	39,700,000	55,423,000
Seriously delinquent securitized single-family securitized loans	2,221,000	2,758,000
Securitized mortgage loans pledged to non-recourse collateralized financing	11,902
Non-Recourse Collateralized Financing, Principal Outstanding	$10,967,000	$13,134,000

Repurchase_Agreements_Details

Repurchase Agreements (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	$3,013,110	$3,580,754
Repurchage agreement, Weighted Average Interest Rate	0.55%	0.61%
Fair Value of Collateral Pledged	3,274,597	3,890,066
Deferred Costs	0	-243
Repurchase Agreement Counterparty, Weighted Average Maturity of Agreements	144 days	114 days
Collateralized Mortgage Obligations [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	9,834	20,651
Repurchage agreement, Weighted Average Interest Rate	1.51%	1.59%
Fair Value of Collateral Pledged	11,000	19,686
Residential Mortgage Backed Securities [Member] | Agency MBS [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	1,977,338	2,522,503
Repurchage agreement, Weighted Average Interest Rate	0.39%	0.42%
Fair Value of Collateral Pledged	2,064,704	2,598,158
Residential Mortgage Backed Securities [Member] | Non-Agency MBS [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	17,594	10,569
Repurchage agreement, Weighted Average Interest Rate	1.57%	1.80%
Fair Value of Collateral Pledged	21,787	12,746
Commercial Mortgage Backed Securities [Member] | Agency MBS [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	253,857	246,849
Repurchage agreement, Weighted Average Interest Rate	0.36%	0.39%
Fair Value of Collateral Pledged	291,103	306,318
Commercial Mortgage Backed Securities [Member] | Non-Agency MBS [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	114,895	303,674
Repurchage agreement, Weighted Average Interest Rate	1.15%	1.27%
Fair Value of Collateral Pledged	140,216	367,859
CMBS IO [Member] | Agency MBS [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	372,609	369,948
Repurchage agreement, Weighted Average Interest Rate	0.92%	1.16%
Fair Value of Collateral Pledged	430,638	449,072
CMBS IO [Member] | Non-Agency MBS [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Repurchase Agreements Accounted for as Secured Borrowings	266,983	106,803
Repurchage agreement, Weighted Average Interest Rate	1.04%	1.27%
Fair Value of Collateral Pledged	$315,149	$136,227

Repurchase_Agreements_Repurcha1

Repurchase Agreements Repurchase Agreements, Term to Original Maturity (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	$3,013,110	$3,580,754
Deferred Costs	0	-243
Less than 30 days [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	250,635	4,736
30 to 90 days [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	617,399	1,176,631
91 to 180 days [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	904,830	1,439,225
6 months to 1 year [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	1,030,569	960,405
1 year or longer [Member]
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	$209,677	$0

Repurchase_Agreements_Repurcha2

Repurchase Agreements Repurchase Agreements, Counterparty Information (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified	Agreements
Counterparty Information [Line Items]
Line of Credit Facility, Amount Outstanding	$247,115
Line of Credit Facility, Maximum Borrowing Capacity	$300,000
Line of Credit Facility, Interest Rate at Period End	1.01%
Number of Counterparties with Borrowings Outstanding	20
Available Repurchase Agreement Counterparties	33

Derivatives_Details

Derivatives (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Derivative [Line Items]
Derivative assets, fair value	$5,727		$18,488
Derivative liabilities, fair value	-35,898		-6,681
Notional amount of derivative instruments added	7,950,000
Notional amount of derivative instruments terminated	-215,000
Derivatives, notional amount	17,525,000		9,790,000
Gain (loss) on derivative instruments, net	-53,393		-10,076		-908
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative assets, aggregate notional amount	440,000		575,000
Derivative liabilities, aggregate notional amount	17,085,000		9,215,000
Interest Rate Swap [Member]
Derivative [Line Items]
Derivative assets, fair value	5,727		18,488
Derivative liabilities, fair value	-3,002		-1,336
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative assets, aggregate notional amount	440,000		575,000
Derivative liabilities, aggregate notional amount	485,000		215,000
Eurodollar Future [Member]
Derivative [Line Items]
Derivative assets, fair value	0
Derivative liabilities, fair value	-32,896		-5,345
Notional amount of derivative instruments added	7,600,000
Notional amount of derivative instruments terminated	0
Derivatives, notional amount	16,600,000		9,000,000
Gain (loss) on derivative instruments, net	-27,551		-19,391		0
Eurodollar Future [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative assets, aggregate notional amount	0	[1]
Derivative liabilities, aggregate notional amount	16,600,000	[1]	9,000,000	[1]
Long [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount of derivative instruments added	275,000
Notional amount of derivative instruments terminated	0
Derivatives, notional amount	275,000		0
Gain (loss) on derivative instruments, net	4,912		0		0
Long [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 37-48 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	0
Weighted-average Fixed Pay Rate	0.00%
Weighted-average Fixed Receive Rate	0.00%
Long [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 49-60 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	250,000
Weighted-average Fixed Pay Rate	2.00%
Weighted-average Fixed Receive Rate	2.00%
Long [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 61-72 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	0
Weighted-average Fixed Pay Rate	0.00%
Weighted-average Fixed Receive Rate	0.00%
Long [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 73-84 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	0
Weighted-average Fixed Pay Rate	0.00%
Weighted-average Fixed Receive Rate	0.00%
Long [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 97-108 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	0
Weighted-average Fixed Pay Rate	0.00%
Weighted-average Fixed Receive Rate	0.00%
Long [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 109-120 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	25,000
Weighted-average Fixed Pay Rate	3.00%
Weighted-average Fixed Receive Rate	3.00%
Short [Member] | Interest Rate Swap [Member]
Derivative [Line Items]
Notional amount of derivative instruments added	75,000
Notional amount of derivative instruments terminated	-215,000
Derivatives, notional amount	650,000		790,000
Gain (loss) on derivative instruments, net	-30,754		9,315		-908
Short [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 37-48 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	185,000
Weighted-average Fixed Pay Rate	0.92%
Weighted-average Fixed Receive Rate	0.92%
Short [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 49-60 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	235,000
Weighted-average Fixed Pay Rate	1.45%
Weighted-average Fixed Receive Rate	1.45%
Short [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 61-72 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	25,000
Weighted-average Fixed Pay Rate	1.61%
Weighted-average Fixed Receive Rate	1.61%
Short [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 73-84 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	25,000
Weighted-average Fixed Pay Rate	2.19%
Weighted-average Fixed Receive Rate	2.19%
Short [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 97-108 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	30,000
Weighted-average Fixed Pay Rate	1.93%
Weighted-average Fixed Receive Rate	1.93%
Short [Member] | Interest Rate Swap [Member] | Interest Rate Swap Agreements, Maturities in Next 109-120 Months [Member]
Derivative [Line Items]
Derivatives, notional amount	$150,000
Weighted-average Fixed Pay Rate	2.17%
Weighted-average Fixed Receive Rate	2.17%
[1]	The Eurodollar futures aggregate notional amount represents the total notional of the 3-month contracts with expiration dates from 2015 to 2020. The maximum notional outstanding for any future 3-month period did not exceed $1,300,000 as of December 31, 2014 and $1,175,000 as of December 31, 2013.

Derivatives_Derivative_Effect_

Derivatives Derivative Effect on Accumulated Other Comprehensive Income (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Reclassification adjustment for cash flow hedges (including de-designated hedges)	$6,788	$13,989	$14,448
Derivative [Line Items]
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	2,577
Dedesignated cash flow hedge amortization	6,788	5,193	0
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	0	8,796	14,448
Scenario, Forecast [Member]
Derivative [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months				$3,460

Offsetting_Assets_and_Liabilit2

Offsetting Assets and Liabilities Offsetting Assets (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Offsetting Assets [Line Items]
Derivative assets, fair value, gross asset	$5,727		$18,488
Derivative assets, fair value, gross liability	0		0
Derivative assets, fair value, amount not offset against collateral	5,727		18,488
Derivative assets, Collateral, Obligation to Return Securities	-1,073	[1]	-193	[1]
Derivative assets, Collateral, Obligation to Return Cash	-4,521	[1]	-12,141	[1]
Derivative assets, fair value, amount offset against collateral	$133		$6,154
[1]	1) Amount 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.

Offsetting_Assets_and_Liabilit3

Offsetting Assets and Liabilities Offsettting Liabilities (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Offsetting Liabilities [Line Items]
Derivative liabilities, fair value, gross liability	$35,898		$6,681
Derivative liabilities, fair value, gross amount offset in balance sheet	0		0
Derivative liabilities, fair value, amount not offset against collateral	35,898		6,681
Derivative, Collateral, Right to Reclaim Securities	-2,494	[1]	-1,299	[1]
Derivative, Collateral, Right to Reclaim Cash	-32,994	[1]	-5,382	[1]
Derivative liabilities, fair value, amount offset against collateral	410		0
Repurchase agreements, gross liability	3,013,110		3,580,754
Repurchase agreements, gross amount offset in balance sheet	0		0
Repurchase agreements, amount not offset against collateral	3,013,110		3,580,754
Repurchase agreements, Collateral, Right to Reclaim Securities	-3,013,110	[1]	-3,580,754	[1]
Repurchase agreements, Collateral, Right to Reclaim Cash	0	[1]	0	[1]
Repurchase agreements, amount offset against collateral	0		0
Total gross liabilities	3,049,008		3,587,435
Total gross liabilities, gross amount offset in balance sheet	0		0
Total liabilities, amount not offset against collateral	3,049,008		3,587,435
Total liabilities, Collateral, Right to Reclaim Securities	-3,015,604	[1]	-3,582,053	[1]
Total liabilities, Collateral, Right to Reclaim Cash	-32,994	[1]	-5,382	[1]
Total liabilities, amount offset against collateral	$410		$0
[1]	1) Amount 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_Instru2

Fair Value of Financial Instruments Fair Value on a Recurring Basis (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	$3,516,239	$4,018,161
Derivative assets	5,727	18,488
Derivative Liabilities	35,898	6,681
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	3,516,239	4,018,161
Derivative assets	5,727	18,488
Total assets carried at fair value	3,521,966	4,036,649
Derivative Liabilities	35,898	6,681
Total liabilities carried at fair value	35,898	6,681
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	0	0
Derivative assets	0	0
Total assets carried at fair value	0	0
Derivative Liabilities	32,896	5,345
Total liabilities carried at fair value	32,896	5,345
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	3,472,282	3,944,681
Derivative assets	5,727	18,488
Total assets carried at fair value	3,478,009	3,963,169
Derivative Liabilities	3,002	1,336
Total liabilities carried at fair value	3,002	1,336
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities	43,957	73,480
Derivative assets	0	0
Total assets carried at fair value	43,957	73,480
Derivative Liabilities	0	0
Total liabilities carried at fair value	$0	$0

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments Significant Unobservable Inputs Level 3 (Details) (Fair Value, Measurements, Recurring [Member], Fair Value, Inputs, Level 3 [Member])	12 Months Ended
	Dec. 31, 2014
Commercial Mortgage Backed Securities [Member]
Fair Value Inputs, Quantitative Information [Abstract]
Fair Value Inputs, Prepayment Rate	20.00%	[1]
Fair Value Inputs, Probability of Default	2.00%	[1]
Fair Value Inputs, Loss Severity	35.00%	[1]
Fair Value Inputs, Discount Rate	9.90%	[1]
Residential Mortgage Backed Securities [Member]
Fair Value Inputs, Quantitative Information [Abstract]
Fair Value Inputs, Prepayment Rate	10.00%	[1]
Fair Value Inputs, Probability of Default	1.00%	[1]
Fair Value Inputs, Loss Severity	20.00%	[1]
Fair Value Inputs, Discount Rate	6.50%	[1]
[1]	Data presented are weighted averages.

Fair_Value_of_Financial_Instru4

Fair Value of Financial Instruments Level 3 (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Principal payments		($51,588)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	26,021
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings		-25
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	73,480	105,245
Unrealized (loss) gain included in OCI	2,178	-6,021
Principal payments	-32,267
Accretion	566	-152
Balance at the end of the period	43,957	73,480
Non-Agency CMBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	26,021
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings		0
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	70,733	100,102
Unrealized (loss) gain included in OCI	2,317	-6,026
Principal payments	-31,253	-49,167
Accretion	236	-197
Balance at the end of the period	42,033	70,733
Non-Agency RMBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings		0
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period	2,747	5,118
Unrealized (loss) gain included in OCI	-139	5
Principal payments	-1,014	-2,421
Accretion	330	45
Balance at the end of the period	1,924	2,747
Other Investments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings		-25
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at the beginning of the period		25
Balance at the end of the period		$0

Fair_Value_of_Financial_Instru5

Fair Value of Financial Instruments Recorded basis and Fair Value (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$5,727		$18,488
Derivative Liabilities, Fair Value Disclosure	35,898		6,681
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	5,727		18,488
Derivative Liabilities, Fair Value Disclosure	35,898		6,681
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities, Fair Value Disclosure	3,516,239		4,018,161
Mortgage loans held for investment, net, Fair Value Disclosure	39,700		55,423
Derivative assets	5,727		18,488
Repurchase Agreements, Fair Value Disclosure	3,013,110		3,580,754
Non-recourse collateralized financing, Fair Value Disclosure	10,786		12,914
Derivative Liabilities, Fair Value Disclosure	35,898		6,681	[1]
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities, Fair Value Disclosure	3,516,239		4,018,161
Mortgage loans held for investment, net, Fair Value Disclosure	35,024	[2]	46,383	[2]
Derivative assets	5,727		18,488
Repurchase Agreements, Fair Value Disclosure	3,013,110		3,580,997	[1]
Non-recourse collateralized financing, Fair Value Disclosure	10,366	[2]	12,414	[2]
Derivative Liabilities, Fair Value Disclosure	$35,898		$6,681
[1]	(2) The difference between the recorded basis of repurchase agreements and their fair value as of December 31, 2013 is the unamortized deferred costs remaining for the 2-year repurchase facility.
[2]	(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 fair value of the Company's Level 3 non-Agency MBS.

Shareholders_Equity_Details

Shareholders' Equity (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2012	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Preferred Stock, Liquidation Preference Per Share	$25								$25
Shareholders' Equity, Common Stock [Roll Forward]
Balance as of beginning of period			54,310,484				54,268,915		54,310,484	54,268,915
Common stock issued under DRIP									16,753	515,257
Common stock issued or redeemed under stock and incentive Plans									471,210	270,158
Common stock forfeited for tax withholding on share-based compensation									-59,336	-52,385
Balance as of end of period	54,739,111			54,310,484					54,739,111	54,310,484
Dividend reinvestment plan, shares authorized	3,000,000								3,000,000
Stock issued during period, remaining shares available, dividend reinvestment plan	2,450,145								2,450,145
Dividends declared per common share	$0.25	$0.25	$0.25	$0.27	$0.27	$0.29	$0.29	$0.25
Stock Repurchase Program, Authorized Amount	$50,000,000								$50,000,000
Stock Repurchased During Period, Shares									0	-872,447
At the market progam [Member]
Shareholders' Equity, Common Stock [Roll Forward]
Common stock issued under ATM program									0	180,986
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage									8.50%
Preferred Stock, Shares Issued	2,300,000			2,300,000					2,300,000	2,300,000
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage									7.63%
Preferred Stock, Shares Issued	2,250,000			2,250,000					2,250,000	2,250,000
Common Stock [Member] | At the market progam [Member]
Shareholders' Equity, Common Stock [Roll Forward]
ATM program, authorized shares remaining	7,416,520								7,416,520

Shareholders_Equity_Sharebased

Shareholders' Equity Share-based Compensation (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based incentive plan, number of shares authorized for issuance	2,500,000
Share-based incentive plan, number of shares remaining for issuance	1,078,908
Total share-based compensation expense	$2,719,000	$2,354,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value	3,703,000	2,708,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Restricted stock outstanding as of beginning of the period	520,969	448,283
Restricted stock granted during the period	457,538	255,158
Restricted stock vested during the period	-246,698	-182,472
Restricted stock outstanding as of end of the period	731,809	520,969
Nonvested restricted stock, fair value remaining to be amortized	4,294,000
Restricted Stock [Member] | Within twelve months [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	2,265,000
Restricted Stock [Member] | One to two years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	1,452,000
Restricted Stock [Member] | Two to three years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	541,000
Restricted Stock [Member] | Three to four years [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options
Nonvested restricted stock, fair value remaining to be amortized	$36,000

Income_Taxes_Details

Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Abstract]
Estimated REIT taxable income	$79,229	$71,765	$73,962
Operating Loss Carryforwards	$120,016
Operating Loss Carryforwards, Limitations on Use	Because the Company incurred an "ownership change" under Section 382 of the Internal Revenue Code ("Section 382"), the company's ability to utilize its NOL carryforward to offset its taxable income after any required dividend distributions is limited to approximately $13,451 per year with any unused amounts being accumulated and carried forward for use in subsequent years.

Related_Party_Transactions_Det

Related Party Transactions (Details) (USD $)	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transaction, Rate	8.00%
Due from Officers or Stockholders	$9,191

Selected_Quarterly_Information1

Selected Quarterly Information (Unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Selected Quarterly Information [Abstract]
Net interest income	$18,634	$19,942	$20,007	$20,186	$22,948	$22,444	$22,526	$21,146	$79,729	$88,104	$78,401
Net income (loss) to common shareholders	1,379	28,572	-3,028	19,266	-6,921	29,442	18,381	-8,293	18,630	60,167	72,006
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$6,234	$14,090	$26,532	$19,813	($6,184)	($67,215)	$27,427	$26,906	$73,762	($26,160)	$127,772
Net income (loss) per common share - basic and diluted	$0.03	$0.52	($0.06)	$0.35	($0.13)	$0.54	$0.34	($0.15)	$0.34	$1.10	$1.35
Dividends declared per common share	$0.25	$0.25	$0.25	$0.27	$0.27	$0.29	$0.29	$0.25

Subsequent_Events_Nonrecognize

Subsequent Events Nonrecognized Subsequent Event (Details) (Subsequent Event [Member], USD $)	3 Months Ended
	Mar. 12, 2015
Subsequent Event [Member]
Subsequent Event [Line Items]
Stock Issued During Period, Shares, Restricted Stock Award, Gross	231,274
Stock Issued During Period, Value, Restricted Stock Award, Gross	$1,917