Invesco Mortgage Capital (IVR) 10-K 20 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 16, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	IVR
Entity Registrant Name	Invesco Mortgage Capital Inc.
Entity Central Index Key	1,437,071
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		111,624,159
Entity Public Float			$ 1,863,746,525

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Mortgage-backed and credit risk transfer securities, at fair value (including pledged securities of $17,474,616 and $14,422,198, respectively)	$ 18,190,754	$ 14,981,331
Commercial loans, held-for-investment	191,808	273,355
Cash and cash equivalents	88,381	161,788
Due from counterparties	620	86,450
Investment related receivable	73,217	90,831
Derivative assets, at fair value	6,896	3,186
Other assets	105,580	109,297
Total assets	18,657,256	15,706,238
Liabilities:
Repurchase agreements	14,080,801	11,160,669
Secured loans	1,650,000	1,650,000
Exchangeable senior notes	143,231	397,041
Derivative liabilities, at fair value	32,765	134,228
Dividends and distributions payable	50,193	50,924
Investment related payable	5,191	9,232
Accrued interest payable	17,845	21,066
Collateral held payable	7,327	1,700
Accounts payable and accrued expenses	2,200	1,534
Due to affiliate	10,825	9,660
Total liabilities	16,000,378	13,436,054
Commitments and contingencies (See Note 16)
Equity:
Common Stock, par value $0.01 per share; 450,000,000 shares authorized; 111,624,159 and 111,594,595 shares issued and outstanding, respectively	1,116	1,116
Additional paid in capital	2,384,356	2,379,863
Accumulated other comprehensive income	261,029	293,668
Retained earnings (distributions in excess of earnings)	(579,334)	(718,303)
Total stockholders’ equity	2,630,491	2,241,560
Non-controlling interest	26,387	28,624
Total equity	2,656,878	2,270,184
Total liabilities and equity	18,657,256	15,706,238
Series A Cumulative Redeemable Preferred Stock
Equity:
Preferred Stock, par value $0.01 per share; 50,000,000 shares authorized:	135,356	135,356
Series B Cumulative Redeemable Preferred Stock
Equity:
Preferred Stock, par value $0.01 per share; 50,000,000 shares authorized:	149,860	149,860
Series C Cumulative Redeemable Preferred Stock
Equity:
Preferred Stock, par value $0.01 per share; 50,000,000 shares authorized:	$ 278,108	$ 0

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Mortgage-backed and credit risk transfer securities, pledged as collateral	$ 17,474,616	$ 14,422,198
Preferred Stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred Stock, shares authorized	50,000,000	50,000,000
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized	450,000,000	450,000,000
Common stock, shares issued	111,624,159	111,594,595
Common stock, shares outstanding	111,624,159	111,594,595
Series A Cumulative Redeemable Preferred Stock
Preferred Stock, dividend rate stated percentage	7.75%	7.75%
Preferred Stock, shares issued	5,600,000	5,600,000
Preferred Stock, shares outstanding	5,600,000	5,600,000
Preferred Stock, aggregate liquidation preference	$ 140,000	$ 140,000
Series B Cumulative Redeemable Preferred Stock
Preferred Stock, dividend rate stated percentage	7.75%	7.75%
Preferred Stock, shares issued	6,200,000	6,200,000
Preferred Stock, shares outstanding	6,200,000	6,200,000
Preferred Stock, aggregate liquidation preference	$ 155,000	$ 155,000
Series C Cumulative Redeemable Preferred Stock
Preferred Stock, dividend rate stated percentage	7.50%
Preferred Stock, shares issued	11,500,000
Preferred Stock, shares outstanding	11,500,000
Preferred Stock, aggregate liquidation preference	$ 287,500

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest Income
Mortgage-backed and credit risk transfer securities		$ 521,547	$ 456,444	$ 523,893
Residential loans	[1]	0	0	110,908
Commercial loans		23,508	22,238	15,331
Total interest income		545,055	478,682	650,132
Interest Expense
Repurchase agreements		163,881	124,000	166,892
Secured loans		19,370	10,887	6,579
Exchangeable senior notes		13,340	22,467	22,461
Asset-backed securities	[1]	0	0	82,041
Total interest expense		196,591	157,354	277,973
Net interest income		348,464	321,328	372,159
Reduction in provision for loan losses		0	0	(213)
Net interest income after reduction in provision for loan losses		348,464	321,328	372,372
Other income (loss)
Gain (loss) on investments, net		(19,704)	(17,542)	(18,005)
Equity in earnings (losses) of unconsolidated ventures		(1,327)	2,392	12,630
Gain (loss) on derivative instruments, net		18,155	(62,815)	(219,048)
Realized and unrealized credit derivative income (loss), net		51,648	61,143	19,782
Net loss on extinguishment of debt		(6,814)	0	0
Other investment income (loss), net		7,381	(5,002)	944
Total other income (loss)		49,339	(21,824)	(203,697)
Expenses
Management fee — related party		37,556	34,541	38,632
General and administrative		7,190	7,265	7,769
Consolidated securitization trusts	[1]	0	0	8,219
Total expenses		44,746	41,806	54,620
Net income		353,057	257,698	114,055
Net income attributable to non-controlling interest		4,450	3,287	1,344
Net income attributable to Invesco Mortgage Capital Inc.		348,607	254,411	112,711
Dividends to preferred stockholders		28,080	22,864	22,864
Net income attributable to common stockholders		$ 320,527	$ 231,547	$ 89,847
Net income attributable to common stockholders
Basic (in usd per share)		$ 2.87	$ 2.07	$ 0.74
Diluted (in usd per share)		$ 2.75	$ 1.98	$ 0.74
Weighted average number of shares of common stock:
Basic (in shares)		111,610,393	111,973,404	121,377,585
Diluted (in shares)		123,040,827	130,254,003	122,843,838
[1]	The consolidated statement of operations for the year ended December 31, 2015 includes income and expenses of consolidated variable interest entities ("VIEs"). We deconsolidated these VIEs in 2015. Refer to Note 2 - “Summary of Significant Accounting Policies” for further discussion.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 353,057	$ 257,698	$ 114,055
Other comprehensive income (loss):
Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net	(9,885)	(37,632)	(191,053)
Reclassification of unrealized (gain) loss on sale of mortgage-backed and credit risk transfer securities to gain (loss) on investments, net	1,508	6,134	(7,484)
Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense	(25,544)	5,154	66,757
Currency translation adjustments on investment in unconsolidated venture	863	128	(32)
Total other comprehensive income (loss)	(33,058)	(26,216)	(131,812)
Comprehensive income (loss)	319,999	231,482	(17,757)
Less: Comprehensive (income) loss attributable to non-controlling interest	(4,032)	(2,939)	245
Less: Dividends to preferred stockholders	(28,080)	(22,864)	(22,864)
Comprehensive income (loss) attributable to common stockholders	$ 287,887	$ 205,679	$ (40,376)

Consolidated Statement of Equit

Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Preferred StockSeries A Preferred Stock	Preferred StockSeries B Preferred Stock	Preferred StockSeries C Preferred Stock	Common Stock	Additional Paid in Capital	Accumulated Other Comprehensive Income (loss)	Retained earnings (Distributions in excess of earnings)	Total Stockholders’ Equity	Non- Controlling Interest
Beginning balance (in shares) at Dec. 31, 2014		5,600,000	6,200,000	0	123,110,454
Beginning balance at Dec. 31, 2014	$ 2,638,850	$ 135,356	$ 149,860	$ 0	$ 1,231	$ 2,532,130	$ 448,847	$ (657,109)	$ 2,610,315	$ 28,535
Increase (Decrease) in Stockholders' Equity
Net income	114,055							112,711	112,711	1,344
Other comprehensive income (loss)	(131,812)						(130,223)		(130,223)	(1,589)
Proceeds from issuance of common stock, net of offering costs (in shares)					12,945
Proceeds from issuance of common stock, net of offering costs	191				$ 0	191			191
Repurchase of shares of common stock (in shares)					(9,539,251)
Repurchase of shares of common stock	(125,595)				$ (95)	(125,500)			(125,595)
Stocks awards (in shares)					35,323
Common stock dividends	(204,051)							(204,051)	(204,051)
Common unit dividends	(2,423)									(2,423)
Preferred stock dividends	(22,864)							(22,864)	(22,864)
Amortization of equity-based compensation	557					551			551	6
Ending balance (in shares) at Dec. 31, 2015		5,600,000	6,200,000	0	113,619,471
Ending balance at Dec. 31, 2015	2,266,908	$ 135,356	$ 149,860	$ 0	$ 1,136	2,407,372	318,624	(771,313)	2,241,035	25,873
Increase (Decrease) in Stockholders' Equity
Net income	257,698							254,411	254,411	3,287
Other comprehensive income (loss)	(26,216)						(25,868)		(25,868)	(348)
Proceeds from issuance of common stock, net of offering costs (in shares)					3,201
Proceeds from issuance of common stock, net of offering costs	35					35			35
Repurchase of shares of common stock (in shares)					(2,063,451)
Repurchase of shares of common stock	(25,000)				$ (20)	(24,980)			(25,000)
Stocks awards (in shares)					35,374
Common stock dividends	(178,537)							(178,537)	(178,537)
Common unit dividends	(2,280)									(2,280)
Preferred stock dividends	(22,864)							(22,864)	(22,864)
Amortization of equity-based compensation	440					434			434	6
Rebalancing of ownership percentage of non-controlling interest	912					(2,998)	912		(2,086)	2,086
Ending balance (in shares) at Dec. 31, 2016		5,600,000	6,200,000	0	111,594,595
Ending balance at Dec. 31, 2016	2,270,184	$ 135,356	$ 149,860	$ 0	$ 1,116	2,379,863	293,668	(718,303)	2,241,560	28,624
Increase (Decrease) in Stockholders' Equity
Net income	353,057							348,607	348,607	4,450
Other comprehensive income (loss)	(33,058)						(32,640)		(32,640)	(418)
Proceeds from issuance of preferred stock, net of offering costs (in shares)				11,500,000
Proceeds from issuance of preferred stock, net of offering costs	278,108			$ 278,108					278,108
Stocks awards (in shares)					29,564
Common stock dividends	(181,931)							(181,931)	(181,931)
Common unit dividends	(2,323)									(2,323)
Preferred stock dividends	(27,707)							(27,707)	(27,707)
Amortization of equity-based compensation	548					541			541	7
Rebalancing of ownership percentage of non-controlling interest	1					3,952	1		3,953	(3,953)
Ending balance (in shares) at Dec. 31, 2017		5,600,000	6,200,000	11,500,000	111,624,159
Ending balance at Dec. 31, 2017	$ 2,656,878	$ 135,356	$ 149,860	$ 278,108	$ 1,116	$ 2,384,356	$ 261,029	$ (579,334)	$ 2,630,491	$ 26,387

Consolidated Statements of Cash

Consolidated Statements of Cash Flows $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Cash Flows from Operating Activities
Net income	$ 353,057	$ 257,698	$ 114,055
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of mortgage-backed and credit risk transfer securities premiums and (discounts), net	95,150	118,248	117,288
Amortization of residential loans and asset-backed securities premiums (discounts), net	0	0	(656)
Amortization of commercial loan origination fees	(337)	(302)	(91)
Reduction in provision for loan losses	0	0	(213)
Unrealized (gain) loss on derivative instruments, net	(27,393)	(99,932)	(9,597)
Unrealized (gain) loss on credit derivatives, net	(28,305)	(42,817)	4,623
(Gain) loss on investments, net	19,704	17,542	18,005
Realized (gain) loss on derivative instruments, net	(67,838)	57,943	44,272
Realized (gain) loss on credit derivatives, net	0	6,017	1,140
Equity in (earnings) losses of unconsolidated ventures	1,327	(2,392)	(12,630)
Amortization of equity-based compensation	548	440	557
Amortization of deferred securitization and financing costs	1,445	2,468	3,146
Amortization of net deferred (gain) loss on de-designated interest rate swaps	(25,544)	5,154	66,757
Net loss on extinguishment of debt	6,814	0	0
(Gain) loss on foreign currency transactions, net	(4,103)	8,260	1,964
Changes in operating assets and liabilities:
(Increase) decrease in operating assets	(7,774)	3,966	5,660
Increase (decrease) in operating liabilities	1,203	(2,578)	4,305
Net cash provided by operating activities	317,954	329,715	358,585
Cash Flows from Investing Activities
Purchase of mortgage-backed and credit risk transfer securities	(6,277,918)	(2,660,925)	(2,352,380)
Purchase of U.S. Treasury Securities	0	(403,105)	0
Proceeds from sale of U.S. Treasury securities	0	524,478	0
(Contributions to) distributions from investments in unconsolidated ventures, net	6,865	7,632	18,183
Change in other assets	(3,457)	623	(12,875)
Principal payments from mortgage-backed and credit risk transfer securities	2,373,953	2,580,695	2,602,138
Proceeds from sale of mortgage-backed and credit risk transfer securities	625,540	1,034,295	907,155
Payments on sale of credit derivatives	0	(6,017)	(1,140)
Payment of premiums for interest rate swaptions	0	0	(1,486)
Settlement (termination) of futures, forwards, swaps, swaptions and TBAs, net	67,838	(56,458)	(33,945)
Purchase of residential loans held-for-investment	0	0	(372,305)
Principal payments from residential loans held-for-investment	0	0	549,565
Principal payments from commercial loans held-for-investment	90,713	15,000	92,796
Origination and advances of commercial loans, net of origination fees	(4,799)	(87,202)	(157,963)
Net cash (used in) provided by investing activities	(3,121,265)	949,016	1,237,743
Cash Flows from Financing Activities
Proceeds from issuance of common stock	0	35	191
Repurchase of common stock	0	(25,000)	(125,595)
Proceeds from (cost of) issuance of preferred stock	278,226	0	(36)
Due from counterparties	(620)	29,445	(53,830)
Change in collateral held payable	5,627	(3,200)	(9,990)
Proceeds from repurchase agreements	146,886,038	127,056,247	140,861,204
Principal repayments of repurchase agreements	(143,964,490)	(128,023,042)	(142,357,783)
Proceeds from asset-backed securities	0	0	336,077
Principal repayments of asset-backed securities	0	0	(518,150)
Proceeds from secured loans	0	125,000	2,325,000
Principal repayments of secured loans	0	(125,000)	(1,925,000)
Extinguishment of exchangeable senior notes	(262,069)	0	0
Payments of deferred costs	(116)	(136)	0
Payments of dividends and distributions	(212,692)	(204,491)	(239,361)
Net cash provided by (used in) financing activities	2,729,904	(1,170,142)	(1,707,273)
Net change in cash and cash equivalents	(73,407)	108,589	(110,945)
Cash and cash equivalents, beginning of period	161,788	53,199	164,144
Cash and cash equivalents, end of period	88,381	161,788	53,199
Supplement Disclosure of Cash Flow Information
Interest paid	220,299	146,840	211,414
Non-cash Investing and Financing Activities Information
Net change in unrealized gain (loss) on mortgage-backed and credit risk transfer securities	(8,377)	(31,498)	(198,537)
Dividends and distributions declared not paid	50,193	50,924	51,734
Net change in investment related payable (receivable)	(25,948)	115,304	(131,440)
Repurchase agreements, not settled	(1,416)	(1,416)	(50)
Change in due from counterparties	$ 86,450	$ (5,886)	$ 1,425

Organization and Business Opera

Organization and Business Operations	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Business Operations	Organization and Business Operations Invesco Mortgage Capital Inc. (the “Company”, “we”) is a Maryland corporation primarily focused on investing in, financing and managing residential and commercial mortgage-backed securities and mortgage loans. We are externally managed and advised by Invesco Advisers, Inc. (our "Manager"), a registered investment adviser and an indirect, wholly-owned subsidiary of Invesco Ltd. (“Invesco”), a leading independent global investment management firm. We conduct our business through IAS Operating Partnership L.P. (the “Operating Partnership”) as its sole general partner. As of December 31, 2017 we owned 98.7% of the Operating Partnership and a wholly-owned subsidiary of Invesco owned the remaining 1.3% . We have one operating segment. We primarily invest in: • Residential mortgage-backed securities ("RMBS") that are guaranteed by a U.S. government agency such as the Government National Mortgage Association, or a federally chartered corporation such as the Federal National Mortgage Association ("Fannie Mae") or the Federal Home Loan Mortgage Corporation ("Freddie Mac") (collectively "Agency RMBS"); • Commercial mortgage-backed securities ("CMBS"); • RMBS that are not guaranteed by a U.S. government agency (“non-Agency RMBS”); • Credit risk transfer securities that are unsecured obligations issued by government-sponsored enterprises ("GSE CRT"); • Residential and commercial mortgage loans; and • Other real estate-related financing agreements. We elected to be taxed as a real estate investment trust (“REIT”) for U.S. federal income tax purposes under the provisions of the Internal Revenue Code of 1986 commencing with our taxable year ended December 31, 2009. To maintain our REIT qualification, we are generally required to distribute at least 90% of our REIT taxable income to our stockholders annually. We operate our business in a manner that permits exclusion from the "Investment Company" definition under the Investment Company Act of 1940.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Consolidation In the opinion of management, the consolidated financial statements reflect all adjustments, consisting of normal recurring accruals, which are necessary for a fair statement of our financial condition and results of operations for the periods presented. All significant intercompany transactions, balances, revenues and expenses are eliminated upon consolidation. Our consolidated financial statements have been prepared in accordance with U.S. GAAP and consolidate the financial statements of the Company and our controlled subsidiaries. During the period from January 1, 2015 through December 9, 2015, the consolidated financial statements also include the results of operations of certain residential loan securitization trusts (the "Residential Securitizations") that meet the definition of a variable interest entity ("VIE"). On December 9, 2015, we completed the sale of certain beneficial interests in the Residential Securitizations and deconsolidated the Residential Securitizations. Refer to Note 3 - "Variable Interest Entities" for additional information regarding the impact of consolidation and deconsolidation of the Residential Securitizations. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and accompanying notes. Examples of estimates include, but are not limited to, estimates of the fair values of financial instruments, interest income on mortgage-backed and credit risk transfer securities, provision for loan losses and other-than-temporary impairment charges. Actual results may differ from those estimates. Translation of Foreign Currencies The functional currency of the Company and its subsidiaries is U.S. dollars. Transactions in foreign currencies are recorded at the rates of exchange prevailing on the date of the transactions. At each balance sheet date, monetary assets and liabilities that are denominated in foreign currencies are remeasured at the rates prevailing at the balance sheet date. Gains and losses arising on revaluation are included in other investment income (loss), net on the consolidated statements of operations. During the years ended December 31, 2017 , 2016 and 2015 , we incurred foreign currency gains of $4.1 million , $8.2 million of losses and $1.9 million of losses, respectively, primarily related to the revaluation of our commercial loan investments denominated in Pound Sterling. Our reporting currency is U.S. dollars. Upon consolidation, the assets and liabilities of our investment in an unconsolidated venture whose functional currency is the Euro is translated to U.S. dollars using the period-end exchange rates. Equity accounts are translated at historical rates, except for the change in retained earnings during the year, which is the result of the income statement translation process. Revenue and expense accounts are translated using the weighted average exchange rate during the period. The cumulative translation adjustments associated with the investment in the unconsolidated venture are recorded in accumulated other comprehensive income (loss), a component of consolidated stockholders’ equity. We generally hedge interest rate and foreign currency exposure with derivative financial instruments. Refer to Note 9 - "Derivatives and Hedging Activities" for further information. Fair Value Measurements We report our mortgage-backed and credit risk transfer securities and derivative assets and liabilities at fair value as determined by an independent pricing service. We generally obtain one price per instrument from our primary pricing service. If the primary pricing service cannot provide a price, we will seek a value from other pricing services. The pricing service uses two types of valuation approaches to determine the valuation of our various mortgage-backed and credit risk transfer securities: a market approach, which uses observable prices and other relevant information that is generated by market transactions involving identical or comparable assets or liabilities; and an income approach, which uses valuation techniques to convert future amounts to a single, discounted present value amount. In instances where sufficient market activity may not exist, the pricing service may utilize proprietary valuation models that may consider market transactions in comparable securities and the various relationships between securities in determining fair value and/or market characteristics to estimate relevant cash flows, which are then discounted to calculate the fair values. Observable inputs may include a combination of benchmark yields, executed trades, broker/dealer quotes, issuer spreads, bids, offers and benchmark securities. In addition, the valuation models utilized by pricing services may consider additional pool level information such as prepayment speeds, default frequencies and default severities, if applicable. We and the pricing service continuously monitor market indicators and economic events to determine whether they may have an impact on our valuations. The pricing service values interest rate swaps and interest rate swaptions under the income approach using valuation models. The significant inputs in these models are readily available in public markets or can be derived from observable market transactions for substantially the full terms of the contracts. The pricing service values U.S. Treasury futures, currency forward contracts and to-be-announced securities (“TBAs”) under the market approach through the use of quoted market prices available in an active market. Overrides of prices from pricing services are rare in the current market environment for the assets we hold. Examples of instances that would cause an override include if we recently traded the same security or there is an indication of market activity that would cause the pricing service price to no longer be indicative of fair value. In the rare instance where a price is adjusted, we have a control process to monitor the reason for such adjustment. To gain comfort that pricing service prices are representative of current market information, we compare the transaction prices of security purchases and sales to the valuation levels provided by the pricing services. Price differences exceeding pre-defined tolerance levels are identified and investigated and may be challenged. Trends are monitored over time and if there are indications that the valuations are not comparable to market activity, the pricing services are asked to provide detailed information regarding their methodology and inputs. Transparency tools are also available from the pricing services which help us understand data points and/or market inputs used for pricing securities. We also review daily price movements for interest rate swaps, interest rate swaptions, U.S. Treasury futures, currency forward contracts and TBAs. Price movements exceeding pre-defined tolerance levels are investigated using an alternate price from another pricing service as well as available market information. Based on our findings, the primary pricing service may be challenged, or in rare cases, overridden with an alternate pricing source. In addition, we perform due diligence procedures on all pricing services on at least an annual basis. A questionnaire is sent to pricing services which requests information such as changes in methodologies, business recovery preparedness, internal controls and confirmation that evaluations are generated based on market data. Physical visits are also made to each pricing service's office. As described in Note 11 - "Fair Value of Financial Instruments," we evaluate the source used to fair value our assets and liabilities and make a determination on its categorization within the fair value hierarchy. If the price of a security is obtained from quoted prices for identical instruments in active markets, the security is classified as a level 1 security. If the price of a security is obtained from quoted prices for similar instruments or model-derived valuations whose inputs are observable, the security is classified as a level 2 security. If the inputs appear to be unobservable, the security would be classified as a level 3 security. Transfers between levels, if any, are determined at the end of the reporting period. Mortgage-Backed and Credit Risk Transfer Securities All of our mortgage-backed securities ("MBS") and GSE CRTs are reported at fair value. Fair value is determined by obtaining valuations from an independent source. If the fair value of a security is not available from a third-party pricing service, or such data appears unreliable, we may estimate the fair value of the security using a variety of methods including other pricing services, discounted cash flow analysis, matrix pricing, option adjusted spread models and other fundamental analysis of observable market factors. We record our purchases of MBS and GSE CRTs on the trade date. Although we generally intend to hold most of our MBS and GSE CRTs until maturity, we may sell any of its mortgage-backed and credit risk transfer securities as part of our overall management of our investment portfolio. We have elected the fair value option for all of our MBS purchased on or after September 1, 2016. Prior to September 1, 2016, we had also elected the fair value option for our RMBS interest-only securities (“RMBS IOs”). RMBS IOs are hybrid financial instruments that contain embedded derivatives. Under the fair value option, changes in fair value are recognized in our consolidated statements of operations. In our view, this election more appropriately reflects the results of our operations because MBS fair value changes are accounted for in the same manner as fair value changes in economic hedging instruments. Except for RMBS IOs, MBS purchased prior to September 1, 2016 are classified as available-for-sale securities. Unrealized gains or losses on available-for-sale securities are recorded in accumulated other comprehensive income, a separate component of stockholders' equity, until sale or disposition of the investment. Upon sale or disposition, the cumulative gain or loss previously reported in stockholders' equity is recognized in income. Realized gains and losses from sales of MBS are determined based upon the specific identification method. We have elected the fair value option for GSE CRTs purchased on or after August 24, 2015. GSE CRTs are hybrid financial instruments that contain embedded derivatives. Coupon payments on the securities are based on LIBOR, and principal payments are based on prepayments, losses and defined credit events in a reference pool of mortgage loans that collateralize Agency RMBS. We elected the fair value option for these securities due to the complexities associated with bifurcation of GSE CRTs into a debt host contract and an embedded derivative. Under the fair value option, changes in fair value for GSE CRTs are recognized in our consolidated statements of operations. GSE CRTs purchased prior to August 24, 2015 are also reported at fair value but are accounted for as hybrid financial instruments consisting of a debt host contract and an embedded derivative. Unrealized gains or losses arising from changes in fair value of the debt host contract, excluding other-than-temporary impairment, are recognized in accumulated other comprehensive income, a separate component of stockholders’ equity, until sale or disposition of the investment. Upon sale or disposition of the debt host contract, the cumulative gain or loss previously reported in stockholders’ equity is recognized in income. Realized gains and losses from sales of GSE CRTs are determined based upon the specific identification method. Realized and unrealized gains or losses arising from changes in fair value of the embedded derivative are recognized in realized and unrealized credit derivative income (loss), net in our consolidated statements of operations. Our interest income recognition policies for MBS and GSE CRTs is described below in the Interest Income Recognition section of this Note 2 to our consolidated financial statements. We consider our portfolio of Agency RMBS to be of high credit quality under applicable accounting guidance. For CMBS, non-Agency RMBS and GSE CRTs, we do not rely on ratings from third party agencies to determine the credit quality of the investment. We use internal models that analyze the loans underlying each security and evaluates factors including, but not limited to, delinquency status, loan-to-value ratios, borrower credit scores, occupancy status and geographic concentration to estimate the expected future cash flows. We place reliance on these internal models in determining credit quality. While CMBS, non-Agency RMBS and GSE CRTs with expected future losses would generally be purchased at a discount to par, the potential for a significant adverse change in expected cash flows remains. We therefore evaluate each security in an unrealized loss position for other-than-temporary impairment at least quarterly. The determination of whether a security is other-than-temporarily impaired involves judgments and assumptions based on subjective and objective factors. Consideration is given to (i) our intent to sell the security and whether it is more likely than not that we will be required to sell the security before recovery of its amortized cost and (ii) the financial condition and near-term prospects of recovery in fair value of the security. This includes a determination of estimated future cash flows through an evaluation of the characteristics of the underlying loans and the structural features of the investment. Underlying loan characteristics reviewed include, but are not limited to, delinquency status, loan-to-value ratios, borrower credit scores, occupancy status and geographic concentration. We recognize in earnings and reflect as a reduction in the cost basis of the security the amount of any other-than-temporary impairment related to credit losses or impairments on securities that we intend to sell or for which it is more likely than not that we will need to sell before recoveries. The amount of the other-than-temporary impairment on debt securities related to other factors is recorded consistent with changes in the fair value of all other available-for-sale securities as a component of consolidated stockholders’ equity in other comprehensive income or loss with no change to the cost basis of the security. Commercial Loans Held-For-Investment We carry commercial loans held-for-investment at amortized cost, net of any provision for loan losses. An individual loan is considered impaired when it is deemed probable that the Company will not be able to recover its investment and any other anticipated future payments. We generally consider the following factors in evaluating whether a commercial loan is impaired: • Loan-to-value ratios; • The most recent financial information available for each loan and associated properties, including net operating income, debt service coverage ratios, occupancy rates, rent rolls, as well as any other factors we consider relevant, including, but not limited to, specific loan trigger events that would indicate an adverse change in expected cash flows or payment delinquency; • Economic trends, both macroeconomic as well as those directly affecting the properties associated with the loans, and the supply and demand trends in the market in which the subject property is located; and • The loan sponsor or borrowing entity’s ability to ensure that properties associated with the loan are managed and operated sufficiently. When an individual commercial loan is deemed to be impaired, we record a provision to reduce the carrying value of the loan to the current present value of expected future cash flows discounted at the loan’s effective interest rate or if the loan is collateral dependent, we reduce the carrying value to the estimated fair value of the collateral, with a corresponding charge to provision for loan losses on our consolidated statements of operations. Interest Income Recognition Mortgage-Backed Securities Interest income on MBS is accrued based on the outstanding principal or notional balance of the securities and their contractual terms. Premiums or discounts are amortized or accreted into interest income over the life of the investment using the effective interest method. Interest income on our MBS where we may not recover substantially all of our initial investment is based on estimated future cash flows. We estimate future expected cash flows at the time of purchase and determine the effective interest rate based on these estimated cash flows and our purchase price. Over the life of the investments, we update these estimated future cash flows and compute a revised yield based on the current amortized cost of the investment. In estimating these future cash flows, there are a number of assumptions that are subject to uncertainties and contingencies, including but not limited to the rate and timing of principal payments (prepayments, repurchases, defaults and liquidations), the pass through or coupon rate, and interest rate fluctuations. These uncertainties and contingencies are difficult to predict and are subject to future events that may impact our estimate and our interest income. Changes in our original or most recent cash flow projections may result in a prospective change in interest income recognized on these securities, or the amortized cost of these securities. For non-Agency RMBS not of high credit quality, when actual cash flows vary from expected cash flows, the difference is recorded as an adjustment to the amortized cost of the security and the security's yield is revised prospectively. For Agency RMBS that cannot be prepaid in such a way that we would not recover substantially all of our initial investment, interest income recognition is based on contractual cash flows. We do not estimate prepayments in applying the effective interest method. Credit Risk Transfer Securities Interest income on GSE CRTs purchased prior to August 24, 2015 is accrued based on the coupon rate of the debt host contract which reflects the credit risk of GSE unsecured senior debt with a similar maturity. Premiums or discounts associated with the purchase of credit risk transfer securities are amortized or accreted into interest income over the life of the debt host contract using the effective interest method. The difference between the coupon rate on the hybrid instrument and the coupon rate on the GSE CRT debt host contract is considered premium income associated with the embedded derivative and is recorded in realized and unrealized credit derivative income (loss), net in our consolidated statements of operations. Interest income on GSE CRTs purchased on or after August 24, 2015 is based on estimated future cash flows. Residential Loans Prior to the deconsolidation of the Residential Securitizations, we recognized interest income from residential loans held by our consolidated VIEs on an accrual basis and amortized the related premiums and discounts into interest income using the effective interest method over the weighted average life of these loans. In estimating the weighted average life of these loans, there were a number of assumptions that were subject to estimation, including the rate and timing of principal payments, defaults, loss severity given default and other factors. Coupon interest was recognized as revenue when earned and deemed collectible or until a loan became more than 90 days past due, at which point the loan was placed on nonaccrual status. Interest previously accrued for loans that had been placed on non-accrual status was reversed against interest income in the period the loan was placed in nonaccrual status. Residential loans delinquent more than 90 days or in foreclosure were characterized as delinquent. Cash principal and interest that was advanced from servicers after a loan becomes greater than 90 days past due was recorded as a liability due to the servicer. When a delinquent loan previously placed on nonaccrual status had cured, meaning all delinquent principal and interest had been remitted by the borrower, the loan was placed back on accrual status. Commercial Loans We recognize interest income from commercial loans when earned and deemed collectible, or until a loan becomes past due based on the terms of the loan agreement. Any related origination fees, net of origination cost are amortized into interest income using the effective interest method over the life of the loan. Interest received after a loan becomes past due or impaired is used to reduce the outstanding loan principal balance. When a delinquent loan previously placed on nonaccrual status has cured, meaning all delinquent principal and interest have been remitted by the borrower, the loan is placed back on accrual status. Alternately, loans that have been individually impaired may be placed back on accrual status if restructured and after the loan is considered re-performing. A restructured loan is considered re-performing when the loan has been current for at least 12 months . Cash and Cash Equivalents We consider all highly liquid investments that have original or remaining maturity dates of three months or less when purchased to be cash equivalents. At December 31, 2017 , we had cash and cash equivalents in excess of the FDIC deposit insurance limit of $ 250,000 per institution. We mitigate our risk of loss by actively monitoring our counterparties. Due from Counterparties / Collateral Held Payable Due from counterparties represents cash posted with our counterparties as collateral for our derivatives and repurchase agreements. Collateral held payable represents cash posted with us by counterparties as collateral under our derivatives and repurchase agreements. To the extent we receive collateral other than cash from our counterparties, such assets are not included in our consolidated balance sheets. Notwithstanding the foregoing, if we either sell such assets or pledge the assets as collateral pursuant to a repurchase agreement, the cash received and the corresponding liability is reflected on the consolidated balance sheets. Investment Related Receivable / Investment Related Payable Investment related receivable consists of receivables for mortgage-backed and credit risk transfer securities that we have sold but have not settled with the buyer and accrued interest and principal paydowns on mortgage-backed and credit risk transfer securities. Investment related payable consists of liabilities for mortgage-backed and credit risk transfer securities that we have purchased but have not settled with the seller. Investments in Unconsolidated Ventures Our non-controlling investments in unconsolidated ventures are included in other assets in our consolidated balance sheets and are accounted for under the equity method. Capital contributions, distributions, profits and losses of the entities are allocated in accordance with the terms of the entities’ operating agreements. Such allocations may differ from the stated percentage interests, if any, as a result of preferred returns and allocation formulas as described in the entities' operating agreements. Repurchase Agreements We finance our purchases of mortgage-backed and credit risk transfer securities primarily through the use of repurchase agreements. Repurchase agreements are treated as collateralized financing transactions and are carried at their contractual amounts, including accrued interest, as specified in the respective agreements. We record the mortgage-backed and credit risk transfer securities and the related repurchase agreement financing on a gross basis in our consolidated balance sheets, and the corresponding interest income and interest expense on a gross basis in our consolidated statements of operations. Secured Loans Our wholly-owned subsidiary, IAS Services LLC, is a member of the Federal Home Loan Bank of Indianapolis ("FHLBI"). As a member of the FHLBI, IAS Services LLC has borrowed funds from the FHLBI in the form of secured advances. FHLBI advances are treated as secured financing transactions and are carried at their contractual amounts. Dividends and Distributions Payable Dividends and distributions payable represent dividends declared at the balance sheet date which are payable to common stockholders, preferred stockholders, and an Invesco wholly-owned subsidiary, the non-controlling interest common unit holder of the Operating Partnership. Earnings (Loss) per Share We calculate basic earnings (loss) per share by dividing net income (loss) attributable to common stockholders for the period by the weighted-average number of shares of our common stock outstanding for that period. Diluted earnings per share takes into account the effect of dilutive instruments, such as units of limited partnership interest in the Operating Partnership ("OP Units"), exchangeable debt, and unvested restricted stock and uses the average share price for the period in determining the number of incremental shares that are to be added to the weighted-average number of shares outstanding. Share-Based Compensation We adopted an equity incentive plan under which our independent directors, as part of their compensation for serving as directors, are eligible to receive quarterly stock awards. In addition, we may compensate the officers and employees of our Manager and its affiliates under this equity incentive plan under the terms of our management agreement. Share-based compensation arrangements include share options, restricted and non-restricted share awards, performance-based awards and share appreciation rights. Compensation related to stock awards to our independent directors is recognized in the consolidated financial statements based on the fair value of the equity or liability instruments issued on the date of grant. Compensation related to stock awards to employees of our Manager and its affiliates is recorded at the estimated fair value of the award over the vesting period of the award. We make an upward or downward adjustment to compensation expense for the difference in the fair value at the date of grant and the date the award is earned. Underwriting Commissions and Offering Costs Underwriting commissions and direct costs incurred in connection with our common and preferred stock offerings are reflected as a reduction of additional paid-in-capital and preferred stock, respectively. Comprehensive Income Our comprehensive income consists of net income, as presented in the consolidated statements of operations, adjusted for unrealized gains and losses on MBS purchased prior to September 1, 2016 and the debt host contract associated with GSE CRTs purchased prior to August 24, 2015; reclassification of amortization of net deferred gains and losses on de-designated interest rate swaps to repurchase agreements interest expense and currency translation adjustments on an investment in an unconsolidated venture. Unrealized gains and losses on our MBS purchased prior to September 1, 2016 and the debt host contract associated with GSE CRTs purchased prior to August 24, 2015 are reclassified into net income upon their sale. Accounting for Derivative Financial Instruments We record all derivatives on our consolidated balance sheets at fair value. At the inception of a derivative contract, we determine whether the instrument will be part of a qualifying hedge accounting relationship or whether we will account for the contract as a trading instrument. We have elected not to apply hedge accounting to all new derivative contracts entered into after January 1, 2014. Changes in the fair value of our derivatives are recorded in gain (loss) on derivative instruments, net in our consolidated statements of operations. Net interest paid or received under our interest rate swaps is also recognized in gain (loss) on derivative instruments, net in our consolidated statements of operations. Prior to 2014, we applied hedge accounting to our interest rate swap agreements. Effective December 31, 2013, we voluntarily discontinued hedge accounting for our interest rate swap agreements by de-designating the interest rate swaps as cash flow hedges. As long as we expect the forecasted transactions that were being hedged (i.e., rollovers of our repurchase agreement borrowings) to still occur, the balance recorded in accumulated other comprehensive income (loss) (“AOCI”) from the interest rate swap activity up through December 31, 2013 will remain in AOCI and be recognized in our consolidated statements of operations as interest expense over the remaining term of the interest rate swaps. We may enter into derivative contracts, such as credit default swaps, that are intended to economically hedge certain of its risks, even though hedge accounting does not apply or we elect not to apply hedge accounting under U.S. GAAP. We are a party to hybrid financial instruments that contain embedded derivative instruments. For securities that we did not elect the fair value option, we assess at inception, whether the economic characteristics of the embedded derivative instruments are clearly and closely related to the economic characteristics of the remaining component of the financial instrument (i.e., the debt host contract), whether the financial instrument is remeasured to fair value through earnings and whether a separate instrument with the same terms as the embedded instrument would meet the definition of a derivative instrument. When it is determined that (1) the embedded instrument possesses economic characteristics that are not clearly and closely related to the economic characteristics of the debt host contract, (2) the financial instrument is not remeasured to fair value through earnings and (3) a separate instrument with the same terms would qualify as a derivative instrument, the embedded instrument qualifies as an embedded derivative that is separated from the debt host contract. The embedded derivative is recorded at fair value, and changes in fair value are recorded in realized and unrealized credit derivative income (loss), net in our consolidated statements of operations. We evaluate the terms and conditions of our holdings of swaptions, futures contracts, currency forward contracts and to-be-announced ("TBA") securities to determine if an instrument has the characteristics of an investment or should be considered a derivative under U.S. GAAP. Accordingly swaptions, futures contracts, currency forward contracts and TBAs having the characteristics of derivatives are accounted for at fair value with such changes recognized in gain (loss) on derivative instruments, net in the consolidated statements of operations. The fair value of these swaptions, futures contracts, currency forward contracts and TBAs is included in derivative assets or derivative liabilities on the consolidated balance sheets. Income Taxes We elected to be taxed as a REIT commencing with our taxable year ended December 31, 2009. Accordingly, we will generally not be subject to U.S. federal and applicable state and local corporate income tax to the extent that we make qualifying distributions to our stockholders, and provided we satisfy on a continuing basis, through actual investment and operating results, the REIT requirements including certain asset, income, distribution and stock ownership tests. If we fail to qualify as a REIT and do not qualify for certain statutory relief provisions, we will be subject to U.S. federal, state and local income taxes and may be precluded from qualifying as a REIT for the four taxable years following the year in which we lost our REIT qualification. Accordingly, our failure to qualify as a REIT could have a material adverse impact on our results of operations and amounts available for distribution to stockholders. Our dividends paid deduction for qualifying dividends to our stockholders is computed using our REIT taxable income as opposed to net income reported on the consolidated financial statements. REIT taxable income will generally differ from net income because the determination of REIT taxable income is based on tax regulations and not financial accounting principles. We have elected to treat one of our subsidiaries as a taxable REIT subsidiary (“TRS”). In general, a TRS may hold assets and engage in activities that we cannot hold or engage in directly and generally m

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2017
Variable Interest Entity Disclosure [Abstract]
Variable Interest Entities	Variable Interest Entities Our maximum risk of loss in VIEs in which we are not the primary beneficiary at December 31, 2017 is presented in the table below. $ in thousands Carrying Amount Company's Maximum Risk of Loss CMBS 3,216,417 3,216,417 Non-Agency RMBS 1,257,608 1,257,608 Investments in unconsolidated ventures 25,972 25,972 Total 4,499,997 4,499,997 Refer to Note 4 - "Mortgage-Backed and Credit Risk Transfer Securities" and Note 6 - "Other Assets" for additional details regarding these investments. On December 9, 2015, we completed the sale of certain beneficial interests (the "Securities") in the Residential Securitizations for $69.0 million (the "Transaction"). The Securities sold included the most subordinated classes of asset-backed securities issued by the Residential Securitizations. As a result of the Transaction, we no longer have the power to direct the activities of the Residential Securitizations through default oversight rights and therefore are no longer the primary beneficiary of the Residential Securitizations. We do not manage the Residential Securitizations or serve as or appoint the loan servicer for the Residential Securitizations. Our risk with respect to each investment in a Residential Securitization was limited to our direct ownership in the Residential Securitization. The residential loans owned by the Residential Securitizations were held solely to satisfy the liabilities of the Residential Securitizations, and the investors in the asset-backed securities issued by the Residential Securitizations had no recourse to the Company. We deconsolidated the assets and liabilities of the Residential Securitizations as of the date of the Transaction. The deconsolidation of the Residential Securitizations did not qualify for presentation and disclosure as discontinued operations. We recorded a loss of $19.6 million on deconsolidation of the Residential Securitizations in our consolidated statement of operations as a component of gain (loss) on investments, net. The following table presents the components of the net loss on deconsolidation of VIEs. $ in thousands As of December 9, 2015 Gain (loss) related to derecognition of Residential Securitizations, net (13,260 ) Gain (loss) related to remeasurement of retained interest, net 3,068 Gain (loss) on sale of the securities, net (9,431 ) Total gain (loss) on deconsolidation of VIEs, net (19,623 ) The following table summarizes the net income (loss) of the Residential Securitizations excluding the loss on deconsolidation: $ in thousands Year ended December 31, 2015 Interest income - Residential loans 110,908 Interest expense - Asset-backed securities 82,041 Net interest income 28,867 Reduction in provision for loan losses (213 ) Net interest income after reduction in provision for loan losses 29,080 Expenses - Consolidated securitization trusts 8,219 Net income 20,861

Mortgage-Backed and Credit Risk

Mortgage-Backed and Credit Risk Transfer Securities	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Mortgage-Backed and Credit Risk Transfer Securities	Mortgage-Backed and Credit Risk Transfer Securities The following tables summarize our MBS and GSE CRT portfolio by asset type at December 31, 2017 and 2016 . December 31, 2017 $ in thousands Principal/ Notional Unamortized Premium (Discount) Amortized Cost Unrealized Gain/ (Loss), net Fair Value Net Weighted Average Coupon (1) Period- end Weighted Average Yield (2) Quarterly Weighted Average Yield (3) Agency RMBS: 15 year fixed-rate 2,917,307 119,120 3,036,427 (61,645 ) 2,974,782 3.08 % 2.17 % 1.98 % 30 year fixed-rate 7,354,211 295,977 7,650,188 (9,648 ) 7,640,540 3.72 % 3.09 % 2.90 % ARM* 238,486 1,609 240,095 1,105 241,200 2.67 % 2.60 % 2.36 % Hybrid ARM 1,696,148 26,066 1,722,214 (2,829 ) 1,719,385 2.70 % 2.54 % 2.25 % Total Agency pass-through (4) 12,206,152 442,772 12,648,924 (73,017 ) 12,575,907 3.40 % 2.79 % 2.58 % Agency-CMO (5) 1,226,539 (942,290 ) 284,249 (10,306 ) 273,943 2.05 % 2.91 % 2.74 % CMBS (6)(7) 3,879,775 (704,097 ) 3,175,678 40,739 3,216,417 3.85 % 4.92 % 4.77 % Non-Agency RMBS (8)(9)(10) 2,785,704 (1,661,683 ) 1,124,021 133,587 1,257,608 2.08 % 7.19 % 7.18 % GSE CRT (11)(12) 757,183 24,306 781,489 85,390 866,879 3.41 % 2.45 % 2.79 % Total 20,855,353 (2,840,992 ) 18,014,361 176,393 18,190,754 3.23 % 3.42 % 3.27 % *Adjustable-rate mortgage ("ARM") (1) Net weighted average coupon as of December 31, 2017 is based on principal/notional balance and is presented net of servicing and other fees. (2) Period-end weighted average yield is based on amortized cost as of December 31, 2017 and incorporates future prepayment and loss assumptions. (3) Quarterly weighted average yield for the period was calculated by dividing interest income, including amortization of premiums and discounts, by the average balance of the amortized cost of our investments. All yields are annualized. (4) We have elected the fair value option for Agency RMBS purchased on or after September 1, 2016 which represent 42.3% of principal/notional balance, 42.0% of amortized cost and 42.2% of fair value. (5) Agency collateralized mortgage obligation ("Agency-CMO") includes interest-only securities ("Agency IO"), which represent 81.8% of principal/notional balance, 20.9% of amortized cost and 18.7% of fair value. (6) CMBS includes interest-only securities which represent 15.8% of principal/ notional balance, 0.5% of amortized cost and 0.6% of fair value. (7) We have elected the fair value option for CMBS purchased on or after September 1, 2016 which represent 25.4% of principal/notional balance, 26.7% of amortized cost and 26.1% of fair value. (8) Non-Agency RMBS held by us is 52.2% variable rate, 37.8% fixed rate and 10.0% floating rate based on fair value. (9) Of the total discount in non-Agency RMBS, $195.3 million is non-accretable based on estimated future cash flows of the securities. (10) Non-Agency RMBS includes interest-only securities, which represent 51.5% of the principal/notional balance, 2.0% of amortized cost and 1.8% of fair value. (11) We have elected the fair value option for GSE CRTs purchased on or after August 24, 2015, which represent 26.7% of the balance based on fair value. As a result, GSE CRTs accounted for under the fair value option are not bifurcated between the debt host contract and the embedded derivative. (12) GSE CRT weighted average coupon and weighted average yield excludes coupon interest associated with embedded derivatives not accounted for under the fair value option that is recorded as realized and unrealized credit derivative income (loss), net. December 31, 2016 $ in thousands Principal/ Notional Balance Unamortized Premium (Discount) Amortized Cost Unrealized Gain/(Loss), net Fair Value Net Weighted Average Coupon (1) Period- end Weighted Average Yield (2) Quarterly Weighted Average Yield (3) Agency RMBS: 15 year fixed-rate 3,460,625 151,526 3,612,151 (54,223 ) 3,557,928 3.11 % 2.19 % 1.99 % 30 year fixed-rate 2,780,806 185,521 2,966,327 15,390 2,981,717 4.37 % 2.61 % 2.57 % ARM* 301,900 2,520 304,420 3,453 307,873 2.69 % 2.59 % 2.16 % Hybrid ARM 2,423,152 42,360 2,465,512 8,789 2,474,301 2.70 % 2.52 % 2.02 % Total Agency pass-through (4) 8,966,483 381,927 9,348,410 (26,591 ) 9,321,819 3.37 % 2.42 % 2.20 % Agency-CMO (5) 1,712,120 (1,368,916 ) 343,204 837 344,041 2.16 % 3.08 % 2.07 % CMBS (6)(7) 3,050,747 (559,857 ) 2,490,890 60,830 2,551,720 3.80 % 4.21 % 4.17 % Non-Agency RMBS (8)(9)(10) 3,838,314 (1,934,269 ) 1,904,045 91,506 1,995,551 2.21 % 5.22 % 5.22 % GSE CRT (11)(12) 707,899 24,320 732,219 35,981 768,200 2.38 % 1.51 % 1.24 % Total 18,275,563 (3,456,795 ) 14,818,768 162,563 14,981,331 3.05 % 3.05 % 2.87 % (1) Net weighted average coupon as of December 31, 2016 is based on principal/notional balance and is presented net of servicing and other fees. (2) Period-end weighted average yield is based on amortized cost as of December 31, 2016 and incorporates future prepayment and loss assumptions. (3) Quarterly weighted average yield for the period was calculated by dividing interest income, including amortization of premiums and discounts, by the average balance of the amortized cost of our investments. All yields are annualized. (4) We have elected the fair value option for Agency RMBS purchased on or after September 1, 2016 which represent 4.3% of principal/notional balance, 4.3% of amortized cost and 4.2% of fair value. (5) Agency collateralized mortgage obligation ("Agency CMO") includes interest-only securities ("Agency IO"), which represent 85.5% of principal/ notional balance, 26.8% of amortized cost and 27.1% of fair value. (6) CMBS includes interest-only securities which represent 20.3% of principal/notional balance, 0.8% of amortized cost and 0.9% of fair value. (7) We have elected the fair value option for CMBS purchased on or after September 1, 2016 which represent 0.4% of principal/notional balance, 0.6% of amortized cost and 0.5% of fair value. (8) Non-Agency RMBS held by us is 45.5% variable rate, 47.2% fixed rate, and 7.3% floating rate based on fair value. (9) Of the total discount in non-Agency RMBS, $252.5 million is non-accretable based on estimated future cash flows of the securities. (10) Non-Agency RMBS includes interest-only securities, which represent 43.5% of principal/notional balance, 1.5% of amortized cost and 1.3% of fair value. (11) We have elected the fair value option for GSE CRTs purchased on or after August 24, 2015, which represent 19.2% of the balance based on fair value. As a result, GSE CRTs accounted for under the fair value option are not bifurcated between the debt host contract and the embedded derivative. (12) GSE CRT weighted average coupon and weighted average yield excludes coupon interest associated with embedded derivatives not accounted for under the fair value option that is recorded as realized and unrealized credit derivative income (loss), net. The following table summarizes our non-Agency RMBS portfolio by asset type as of December 31, 2017 and 2016 . $ in thousands December 31, 2017 % of Non-Agency December 31, 2016 % of Non-Agency Prime 649,671 51.6 % 889,658 44.6 % Alt-A 393,899 31.3 % 447,213 22.4 % Re-REMIC 173,110 13.7 % 364,301 18.2 % Subprime/reperforming 40,928 3.4 % 294,379 14.8 % Total Non-Agency 1,257,608 100.0 % 1,995,551 100.0 % The following table summarizes the credit enhancement provided to our re-securitization of real estate mortgage investment conduit ("Re-REMIC") holdings as of December 31, 2017 and 2016 . Percentage of Re-REMIC Holdings at Fair Value Re-REMIC Subordination (1) December 31, 2017 December 31, 2016 0% - 10% 34.5 % 17.6 % 10% - 20% 3.7 % 7.4 % 20% - 30% 12.3 % 13.5 % 30% - 40% 18.4 % 15.7 % 40% - 50% 9.6 % 27.0 % 50% - 60% 19.7 % 16.1 % 60% - 70% 1.8 % 2.7 % Total 100.0 % 100.0 % (1) Subordination refers to the credit enhancement provided to the Re-REMIC tranche held by us by any junior Re-REMIC tranche or tranches in a resecuritization. This figure reflects the percentage of the balance of the underlying securities represented by any junior tranche or tranches at the time of resecuritization. Generally, principal losses on the underlying securities in excess of the subordination amount would result in principal losses on the Re-REMIC tranche held by us. Approximately 57.5% of our Re-REMIC holdings are not senior tranches. The components of the carrying value of our MBS and GSE CRT portfolio at December 31, 2017 and 2016 are presented below. $ in thousands December 31, 2017 December 31, 2016 Principal/ notional balance 20,855,353 18,275,563 Unamortized premium 521,626 476,314 Unamortized discount (3,362,618 ) (3,933,109 ) Gross unrealized gains 341,656 302,099 Gross unrealized losses (165,263 ) (139,536 ) Fair value 18,190,754 14,981,331 The following table summarizes our MBS and GSE CRT portfolio according to estimated weighted average life classifications as of December 31, 2017 and 2016 . $ in thousands December 31, 2017 December 31, 2016 Less than one year 135,559 121,076 Greater than one year and less than five years 7,934,836 6,719,923 Greater than or equal to five years 10,120,359 8,140,332 Total 18,190,754 14,981,331 The following tables present the estimated fair value and gross unrealized losses of our MBS and GSE CRTs by length of time that such securities have been in a continuous unrealized loss position at December 31, 2017 and 2016 . December 31, 2017 Less than 12 Months 12 Months or More Total $ in thousands Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Agency RMBS: 15 year fixed-rate 111,020 (321 ) 26 2,406,021 (67,285 ) 133 2,517,041 (67,606 ) 159 30 year fixed-rate 3,677,576 (20,730 ) 107 963,547 (27,158 ) 56 4,641,123 (47,888 ) 163 ARM 101,173 (902 ) 12 — — — 101,173 (902 ) 12 Hybrid ARM 614,321 (4,189 ) 73 517,642 (8,091 ) 47 1,131,963 (12,280 ) 120 Total Agency pass through (1) 4,504,090 (26,142 ) 218 3,887,210 (102,534 ) 236 8,391,300 (128,676 ) 454 Agency-CMO (2) 75,299 (10,433 ) 44 81,988 (2,309 ) 5 157,287 (12,742 ) 49 CMBS (3) 892,553 (17,612 ) 81 135,139 (3,792 ) 12 1,027,692 (21,404 ) 93 Non-Agency RMBS 84,439 (709 ) 15 96,263 (1,732 ) 11 180,702 (2,441 ) 26 Total 5,556,381 (54,896 ) 358 4,200,600 (110,367 ) 264 9,756,981 (165,263 ) 622 (1) Amounts disclosed include Agency RMBS with a fair value of $3.4 billion for which the fair value option has been elected. Such securities have unrealized losses of $22.8 million . (2) Fair value includes unrealized losses on Agency IO of $10.1 million and unrealized losses on CMO of $2.7 million . (3) Amounts disclosed include CMBS with a fair value of $596.0 million for which the fair value option has been elected. Such securities have unrealized losses of $8.9 million . December 31, 2016 Less than 12 Months 12 Months or More Total $ in thousands Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Agency RMBS: 15 year fixed-rate 2,781,777 (66,506 ) 127 65,964 (1,556 ) 17 2,847,741 (68,062 ) 144 30 year fixed-rate 747,719 (15,409 ) 45 547,763 (18,004 ) 27 1,295,482 (33,413 ) 72 ARM 120,540 (326 ) 9 1,091 (7 ) 1 121,631 (333 ) 10 Hybrid ARM 1,356,687 (9,922 ) 99 252 (4 ) 2 1,356,939 (9,926 ) 101 Total Agency pass through (1) 5,006,723 (92,163 ) 280 615,070 (19,571 ) 47 5,621,793 (111,734 ) 327 Agency-CMO (2) 163,114 (3,812 ) 28 22,792 (952 ) 3 185,906 (4,764 ) 31 CMBS (3) 401,016 (6,733 ) 36 47,219 (804 ) 6 448,235 (7,537 ) 42 Non-Agency RMBS 287,647 (7,861 ) 42 497,863 (6,671 ) 36 785,510 (14,532 ) 78 GSE CRT (4) — — — 35,935 (969 ) 3 35,935 (969 ) 3 Total 5,858,500 (110,569 ) 386 1,218,879 (28,967 ) 95 7,077,379 (139,536 ) 481 (1) Amounts disclosed include Agency RMBS with a fair value of $149.7 million for which the fair value option has been elected. Such securities have unrealized losses of $4.0 million . (2) Fair value includes unrealized losses on Agency IO of $3.0 million and unrealized losses on CMO of $1.7 million . (3) Amounts disclosed includes CMBS with a fair value of $13.9 million for which the fair value option has been elected. Such securities have unrealized losses of $613,000 . (4) Fair value includes unrealized losses on both the debt host contract and the embedded derivative. Gross unrealized losses on our Agency RMBS and CMO were $128.7 million and $2.7 million , respectively, at December 31, 2017 . Due to the inherent credit quality of Agency RMBS and CMO, we determined that at December 31, 2017 , any unrealized losses on our Agency RMBS and CMO portfolio are not other than temporary. Gross unrealized losses on our Agency IO, CMBS and non-Agency RMBS were $33.9 million at December 31, 2017 . We do not consider these unrealized losses to be credit related, but rather due to non-credit related factors such as interest rate spreads, prepayment speeds and market fluctuations. These investment securities are included in our assessment for other-than-temporary-impairment on a quarterly basis. We assess our investment securities for other-than-temporary impairment ("OTTI") on a quarterly basis. When the fair value of an investment is less than its amortized cost at the balance sheet date of the reporting period for which impairment is assessed, the impairment is designated as either "temporary" or "other-than-temporary." This analysis includes a determination of estimated future cash flows through an evaluation of the characteristics of the underlying loans and the structural features of the investment. Underlying loan characteristics reviewed include, but are not limited to, delinquency status, loan-to-value ratios, borrower credit scores, occupancy status and geographic concentration. The following table represents OTTI included in earnings for the years ended December 31, 2017 and 2016 . We did not record any OTTI for the year ended December 31, 2015 . Years Ended December 31, $ in thousands 2017 2016 RMBS interest-only securities 11,208 8,334 Non-Agency RMBS (1) 754 575 Total 11,962 8,909 (1) Amounts disclosed relate to credit losses on debt securities for which a portion of an other-than-temporary impairment was recognized in other comprehensive income. OTTI on RMBS interest-only securities was recorded as a reclassification from an unrealized to realized loss within gain (loss) on investments, net on the consolidated statement of operations because we account for these securities under the fair value option. As of December 31, 2017 , we did not intend to sell the securities and determined that it was not more likely than not that we will be required to sell the securities. The following table summarizes the components of our total gain (loss) on investments, net for the years ended December 31, 2017 , 2016 and 2015 . As of December 31, 2017 , $6.5 billion ( December 31, 2016 : $427.5 million ) or 35.6% ( December 31, 2016 : 2.9% ) of our MBS and GSE CRT are accounted for under the fair value option. Under the fair value option, changes in fair value are recognized as a component of gain (loss) on investments, net in our consolidated statements of operations. Years Ended December 31, $ in thousands 2017 2016 2015 Gross realized gains on sale of investments 2,208 14,196 13,346 Gross realized losses on sale of investments (3,873 ) (21,635 ) (11,114 ) Other-than-temporary impairment losses (11,962 ) (8,909 ) — Net unrealized gains and losses on MBS accounted for under the fair value option (21,368 ) (5,791 ) (558 ) Net unrealized gains and losses on GSE CRT accounted for under the fair value option 15,269 4,598 (56 ) Net unrealized gains and losses on trading securities 22 (1 ) — Total gain (loss) on investments, net (1) (19,704 ) (17,542 ) 1,618 (1) Balance as of December 31, 2015 excludes the loss on deconsolidation of VIEs of $19.6 million . Refer to Note 3 - "Variable Interest Entities" for further discussion. The following tables present components of interest income recognized on our MBS and GSE CRT portfolio for the years ended December 31, 2017 , 2016 and 2015 . GSE CRT interest income excludes coupon interest associated with embedded derivatives not accounted for under the fair value option that is recorded as realized and unrealized credit derivative income (loss), net. For the Year ended December 31, 2017 $ in thousands Coupon Interest Net (Premium Amortization)/ Discount Accretion Interest Income Agency 392,248 (107,702 ) 284,546 CMBS 131,005 (4,268 ) 126,737 Non-Agency 70,849 18,769 89,618 GSE CRT 22,164 (1,949 ) 20,215 Other 431 — 431 Total 616,697 (95,150 ) 521,547 For the Year ended December 31, 2016 $ in thousands Coupon Interest Net (Premium Amortization)/Discount Accretion Interest Income Agency 346,783 (116,991 ) 229,792 CMBS 122,636 (11,536 ) 111,100 Non-Agency 94,206 13,529 107,735 GSE CRT 9,575 (3,192 ) 6,383 Other 1,492 (58 ) 1,434 Total 574,692 (118,248 ) 456,444 For the Year ended December 31, 2015 $ in thousands Coupon Interest Net (Premium Amortization)/Discount Accretion Interest Income Agency 372,610 (121,170 ) 251,440 CMBS 149,977 (11,322 ) 138,655 Non-Agency 110,885 18,287 129,172 GSE CRT 6,681 (3,088 ) 3,593 Other 1,028 5 1,033 Total 641,181 (117,288 ) 523,893

Commercial Loans Held-for-Inves

Commercial Loans Held-for-Investment	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Commercial Loans Held-for-Investment	Commercial Loans Held-for-Investment The following tables summarize commercial loans held-for-investment as of December 31, 2017 and 2016 that we purchased or originated. December 31, 2017 $ in thousands Number of loans Principal Balance Unamortized (fees)/ costs, net Carrying value Weighted Average Coupon Weighted Average Years to Maturity (1) Mezzanine loans 8 191,894 (86 ) 191,808 8.52 % 1.2 December 31, 2016 $ in thousands Number of loans Principal Balance Unamortized (fees)/ costs, net Carrying value Weighted Average Weighted Average Years to Maturity (1) Mezzanine loans 10 273,666 (311 ) 273,355 8.14 % 1.6 (1) Weighted average years to maturity is based on the contractual maturity date. Certain loans may contain either an option to prepay or an option to extend beyond their contractual maturity dates as specified in the respective loan agreements. These loans were not impaired, and no provision for loan loss has been recorded as of December 31, 2017 and 2016 based on our analysis of credit quality factors as discussed in Note 2 - "Summary of Significant Accounting Policies".

Other Assets

Other Assets	12 Months Ended
	Dec. 31, 2017
Schedule of Investments [Abstract]
Other Assets	Other Assets The following table summarizes our other assets as of December 31, 2017 and 2016 : $ in thousands December 31, 2017 December 31, 2016 FHLBI stock 74,250 74,250 Investments in unconsolidated ventures 25,972 33,301 Investment in exchange-traded fund 3,979 500 Prepaid expenses and other assets 1,379 1,246 Total 105,580 109,297 IAS Services LLC, our wholly-owned subsidiary, is required to purchase and hold FHLBI stock as a condition of membership in FHLBI. The stock is recorded at cost. We have invested in unconsolidated ventures that are managed by an affiliate of our Manager. The unconsolidated ventures invest in our target assets. Refer to Note 16 - "Commitments and Contingencies" for additional details regarding our commitments to these unconsolidated ventures. We have invested in an exchange-traded fund that is managed by an affiliate of our Manager. The exchange-traded fund invests in our target assets.

Borrowings

Borrowings	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Borrowings	Borrowings We finance the majority of our investment portfolio through repurchase agreements, secured loans and exchangeable senior notes. The following tables summarize certain characteristics of our borrowings at December 31, 2017 and 2016 . Refer to Note 8 - "Collateral Positions" for collateral pledged under our repurchase agreements and secured loans. $ in thousands December 31, 2017 Amount Outstanding Weighted Average Interest Rate Weighted Average Remaining Maturity (Days) Repurchase Agreements: Agency RMBS 11,111,755 1.58 % 25 CMBS 1,396,330 2.61 % 9 Non-Agency RMBS 915,225 2.77 % 31 GSE CRT 657,491 2.78 % 24 Total Repurchase Agreements 14,080,801 1.82 % 25 Secured Loans 1,650,000 1.52 % 2,317 Exchangeable Senior Notes (1) 143,410 5.00 % 74 Total Borrowings 15,874,211 1.82 % 263 $ in thousands December 31, 2016 Amount Weighted Weighted Repurchase Agreements: Agency RMBS 8,148,220 0.93 % 32 CMBS 944,718 1.86 % 16 Non-Agency RMBS 1,519,859 2.06 % 28 GSE CRT 547,872 2.25 % 16 Total Repurchase Agreements 11,160,669 1.23 % 30 Secured Loans 1,650,000 0.74 % 2,682 Exchangeable Senior Notes (1) 400,000 5.00 % 439 Total Borrowings 13,210,669 1.28 % 373 (1) The carrying value of exchangeable senior notes is $143.2 million and $397.0 million as of December 31, 2017 and 2016 , respectively. The carrying value is net of unamortized debt issuance costs of $179,000 and $3.0 million as of December 31, 2017 and 2016 , respectively. The following table shows the aggregate amount of maturities of our outstanding borrowings: $ in thousands As of December 31, 2018 14,224,211 2019 — 2020 300,000 2021 100,000 2022 — Thereafter 1,250,000 Total 15,874,211 The following tables summarize certain characteristics of our repurchase agreements and secured loans at December 31, 2017 and 2016 . December 31, 2017 $ in thousands Amount Outstanding Percent of Total Amount Outstanding MBS and GSE CRT Pledged as Collateral (1) Repurchase Agreement Counterparties: HSBC 1,745,684 11.2 % 1,839,411 ING Financial Markets 1,482,603 9.4 % 1,571,061 RBC 1,144,856 7.3 % 1,375,285 Industrial and Commercial Bank of China 1,038,844 6.6 % 1,102,543 E D & F Man Capital Markets 1,028,437 6.5 % 1,085,429 Mirae Asset Securities 958,756 6.1 % 1,018,664 MUFG Securities 865,201 5.5 % 936,071 Citigroup 724,094 4.6 % 841,977 Amherst Pierpont Securities 722,080 4.6 % 764,713 KGS-Alpha Capital Markets 461,098 2.9 % 491,313 JP Morgan 451,941 2.9 % 523,590 Societe Generale 386,737 2.5 % 495,093 BNP Paribas Securities 348,340 2.2 % 388,091 South Street Securities 332,623 2.1 % 354,689 Goldman Sachs 324,152 2.1 % 419,713 Mizuho Securities 310,835 2.0 % 330,555 Guggenheim Liquidity Services 306,081 1.9 % 322,452 Bank of Nova Scotia 289,705 1.8 % 301,715 Natixis Securities 275,764 1.8 % 302,291 All other repurchase agreement counterparties (2) 882,970 5.5 % 1,058,759 Total Repurchase Agreement Counterparties 14,080,801 89.5 % 15,523,415 Secured Loans Counterparty: FHLBI 1,650,000 10.5 % 1,927,496 Total 15,730,801 100.0 % 17,450,911 (1) Amounted pledged as collateral is measured at fair value as described in Note 2 - "Summary of Significant Accounting Policies." (2) Represents amounts outstanding with seven counterparties. December 31, 2016 $ in thousands Amount Outstanding Percent of Total Amount Outstanding MBS and GSE CRT Pledged as Collateral (1) Repurchase Agreement Counterparties: HSBC 1,401,966 11.2 % 1,468,793 ING Financial Markets 1,142,200 8.9 % 1,216,492 RBC 1,098,631 8.6 % 1,293,336 Industrial and Commercial Bank of China 707,616 5.5 % 748,503 MUFG Securities 703,382 5.5 % 740,404 Amherst Pierpont Securities 681,853 5.3 % 717,663 South Street Securities 675,660 5.3 % 713,330 Goldman Sachs 486,430 3.8 % 623,400 Bank of Nova Scotia 479,105 3.7 % 500,578 JP Morgan 477,947 3.7 % 554,494 KGS-Alpha Capital Markets 441,541 3.4 % 475,858 Citigroup 427,185 3.3 % 534,875 E D & F Man Capital Markets 405,615 3.2 % 430,896 Guggenheim Liquidity Services 356,149 2.8 % 377,030 Natixis Securities 336,202 2.6 % 362,432 Societe Generale 325,393 2.5 % 427,200 BNP Paribas Securities 307,641 2.4 % 346,484 All other repurchase agreement counterparties (2) 706,153 5.4 % 912,536 Total Repurchase Agreement Counterparties: 11,160,669 87.1 % 12,444,304 Secured Loans Counterparty: FHLBI 1,650,000 12.9 % 1,931,582 Total 12,810,669 100.0 % 14,375,886 (1) Amounted pledged as collateral is measured at fair value as described in Note 2 - "Summary of Significant Accounting Policies." (2) Represents amount outstanding with six counterparties. Repurchase Agreements Repurchase agreements bear interest at a contractually agreed upon rate and have maturities ranging from one month to twelve months . Repurchase agreements are being accounted for as secured borrowings since we maintain effective control of the financed assets. Repurchase agreements are subject to certain financial covenants. We were in compliance with these covenants at December 31, 2017 . Our repurchase agreement collateral ratio (MBS and GSE CRT pledged as collateral/Amount Outstanding) was 110% as of December 31, 2017 (December 31, 2016 : 112% ). Secured Loans Our wholly-owned captive insurance subsidiary, IAS Services LLC, is a member of the FHLBI. As a member of the FHLBI, IAS Services LLC has borrowed funds from the FHLBI in the form of secured loans. As of December 31, 2017 , IAS Services LLC, had $1.65 billion in outstanding secured loans from the FHLBI. These secured loans have floating rates that are based on the three-month FHLB swap rate plus a spread. For the year ended December 31, 2017 , IAS Services LLC had weighed average borrowings of $1.65 billion with a weighted average borrowing rate of 1.17% and a weighted average maturity of 6.3 years. The Federal Housing Finance Agency’s ("FHFA") final rule governing Federal Home Loan Bank membership (the “FHFA Rule”) was effective on February 19, 2016. The FHFA Rule permits existing captive insurance companies, such as IAS Services LLC, to remain members until February 2021. New advances or renewals that mature beyond February 2021 are prohibited. The FHLBI has indicated it will honor the contractual maturity dates of existing advances to IAS Services LLC that were made prior to February 19, 2016 and extend beyond February 2021. We do not expect there to be any impact to our existing FHLBI borrowings under the FHFA rule. The ability to borrow from the FHLBI is subject to our continued creditworthiness, pledging of sufficient eligible collateral to secure advances, and compliance with certain agreements with FHLBI and FHFA rules. As discussed in Note 6 - "Other Assets," IAS Services LLC is required to purchase and hold a certain amount of FHLBI stock, which is based, in part, upon the outstanding principal balance of secured loans from the FHLBI. Exchangeable Senior Notes In 2013, our wholly-owned subsidiary, IAS Operating Partnership LP, issued $400.0 million in aggregate principal amount of Exchangeable Senior Notes (the “Notes”) due March 15, 2018 . As of December 31, 2017 , we had $143.4 million in Notes outstanding. The Notes bear interest at 5.00% per annum, payable semi-annually in arrears on March 15 and September 15 of each year. The Notes may be exchanged for shares of our common stock at the applicable exchange rate defined in the indenture governing the Notes between the Company and the Bank of New York Mellon Trust as Trustee at any time prior to the close of business on March 13, 2018. We have sufficient liquidity through available cash and cash equivalents and additional borrowing capacity through repurchase agreements to retire the Notes when they mature on March 15, 2018. The Notes are reported on our consolidated balance sheets net of unamortized debt issuance costs. Debt issuance costs are amortized as an adjustment to interest expense using the effective interest method over the stated legal maturity of the Notes. The following table summarizes retirements of the Notes during the year ended December 31, 2017 . $ in thousands Year Ended December 31, 2017 Reacquisition price 262,069 Par value of Notes retired (256,590 ) Write off of unamortized debt issuance cost associated with Notes retired 1,335 Net loss on extinguishment of debt 6,814 Accrued interest payable on the Notes was approximately $2.1 million as of December 31, 2017 ( 2016 : $5.9 million ).

Collateral Positions

Collateral Positions	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Collateral Positions	Collateral Positions The following table summarizes the fair value of collateral that we have pledged under our repurchase agreements, secured loans, interest rate swaps and currency forward contracts as of December 31, 2017 and 2016 . Refer to Note 2 - "Summary of Significant Accounting Policies - Fair Value Measurements" for a description of how we determine fair value. RMBS, CMBS and GSE CRT collateral pledged is included in mortgage-backed and credit risk transfer securities on our consolidated balance sheets. Cash collateral pledged on bilateral swaps and currency forwards is classified as due from counterparties on our consolidated balance sheets. Cash collateral held on bilateral swaps that is not restricted for use is included in cash and cash equivalents on our consolidated balance sheets and the liability to return the collateral is included in collateral held payable. Non-cash collateral held is only recognized if the counterparty defaults or if we sell the pledged collateral. As of December 31, 2017 and 2016 , we did not recognize any non-cash collateral held. $ in thousands As of Collateral Pledged December 31, 2017 December 31, 2016 Repurchase Agreements: Agency RMBS 11,788,765 8,654,233 CMBS 1,737,831 1,168,309 Non-Agency RMBS 1,143,373 1,887,550 GSE CRT 853,446 734,212 Total repurchase agreement collateral pledged 15,523,415 12,444,304 Secured Loans: Agency RMBS 623,181 585,504 CMBS 1,304,315 1,346,078 Total secured loans collateral pledged 1,927,496 1,931,582 Interest Rate Swaps and Currency Forward Contracts: Agency RMBS 23,705 46,312 Cash (1) 620 86,450 Total interest rate swaps and currency forward contracts collateral pledged 24,325 132,762 Total: Mortgage-backed and GSE CRT securities 17,474,616 14,422,198 Cash 620 86,450 Total collateral pledged 17,475,236 14,508,648 Collateral Held December 31, 2017 December 31, 2016 Interest Rate Swaps: Cash 7,327 1,700 Non-cash collateral — 536 Total collateral held 7,327 2,236 (1) Cash collateral pledged on our currency forward contracts was $620,000 as of December 31, 2017 . We did no t pledge any collateral on our currency forward contracts as of December 31, 2016 . Repurchase Agreements Collateral posted with our repurchase agreement counterparties is segregated in our books and records. The repurchase agreement counterparties have the right to resell and repledge the collateral posted but have the obligation to return the pledged collateral, or substantially the same collateral if agreed to by us, upon maturity of the repurchase agreement. Under the repurchase agreements, the respective lender retains the contractual right to mark the underlying collateral to fair value as determined by a pricing service agreed to by the respective lender and us. We would be required to provide additional collateral or fund margin calls if the value of pledged assets declines. We intend to maintain a level of liquidity that will enable us to meet margin calls. Secured Loans The ability to borrow from the FHLBI is subject to our continued creditworthiness, pledging of sufficient eligible collateral to secure advances, and compliance with certain agreements with FHLBI and FHFA rules. Collateral posted with the FHLBI is held in trust for the benefit of the FHLBI and is not commingled with our other assets. The FHLBI does not have the right to resell or repledge collateral posted unless an event of default occurs. The FHLBI retains the right to mark the underlying collateral for FHLBI advances to fair value as determined by the FHLBI in its sole discretion. IAS Services LLC would be required to provide additional collateral or fund margin calls if the value of pledged assets declines. Interest Rate Swaps Collateral pledged with our interest rate swap counterparties is segregated in our books and records. We have two types of interest rate swap agreements: bilateral interest rate swaps that are governed by an International Swaps and Derivatives Association ("ISDA") agreement and interest rate swaps that are centrally cleared by a registered clearing organization through a Futures Commission Merchant ("FCM"). Interest rate swaps that are governed by an ISDA agreement provide for bilateral collateral pledging based on the counterparties' market value. The counterparties have the right to repledge the collateral posted, but have the obligation to return the pledged collateral, or substantially the same collateral, if agreed to by us, as the market value of the interest rate swaps change. We are required to pledge initial margin and daily variation margin for our interest rate swaps that are centrally cleared. FCM determines the fair value of our centrally cleared swaps, including daily variation margin. As a result of rulebook changes governing central clearing activities effective January 3, 2017, the daily variation margin payment for centrally cleared interest rate swaps is characterized as settlement of the derivative itself rather than collateral. As a result of this change, cash collateral pledged on our centrally cleared interest rate swaps is settled against the fair value of these swaps. Currency Forward Contracts Collateral pledged with our currency forward counterparty is segregated in our books and records. Eligible collateral to be pledged can be in the form of cash or securities. Our currency forward contract provides for bilateral collateral pledging based on the counterparties' market value. The counterparties have the right to repledge the collateral posted, but have the obligation to return the pledged collateral, or substantially the same collateral, if agreed to by us, as the market value of the currency forward contracts change.

Derivatives and Hedging Activit

Derivatives and Hedging Activities	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivatives and Hedging Activities Risk Management Objective of Using Derivatives We are exposed to certain risks arising from both our business operations and economic conditions. We principally manage our exposures to a wide variety of business and operational risks through management of our core business activities. We manage economic risks, including interest rate, liquidity, credit and foreign exchange rate risk primarily by managing the amount, sources, and duration of our investments, debt funding, and the use of derivative financial instruments. Specifically, we enter into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. Our derivative financial instruments are used to manage differences in the amount, timing, and duration of our known or expected cash receipts and our known or expected cash payments principally related to our investments and borrowings. The following table summarizes changes in the notional amount of our derivative instruments during 2017 : $ in thousands Notional Amount as of January 1, 2017 Additions Settlement, Notional Amount as Interest Rate Swaps 6,500,000 2,620,000 — 9,120,000 Currency Forward Contracts 62,308 284,328 (269,777 ) 76,859 Credit Derivatives 569,966 — (16,473 ) 553,493 Total 7,132,274 2,904,328 (286,250 ) 9,750,352 Interest Rate Swaps Our repurchase agreements are usually settled on a short-term basis ranging from one to twelve months. At each settlement date, we typically refinance each repurchase agreement at the market interest rate at that time. In addition, our secured loans have floating interest rates. As such, we are exposed to changing interest rates. Our objectives in using interest rate derivatives are to add stability to interest expense and to manage our exposures to interest rate movements. To accomplish these objective, we primarily use interest rate swaps as part of our interest rate risk management strategy. Interest rate swaps involve the receipt of variable-rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Effective December 31, 2013, we voluntarily discontinued cash flow hedge accounting for our interest rate swaps to gain greater flexibility in managing interest rate exposures. Amounts recorded in AOCI before we discontinued cash flow hedge accounting for our interest rate swaps are reclassified to interest expense on repurchase agreements on the consolidated statements of operations as interest is accrued and paid on the related repurchase agreements over the remaining life of the interest rate swap agreements. We reclassified $25.5 million as a decrease ( 2016 : $5.2 million as an increase) to interest expense for the year ended December 31, 2017 . During the next 12 months, we estimate that $25.8 million will be reclassified as a decrease to interest expense, repurchase agreements. As of December 31, 2017 , $123.9 million ( December 31, 2016 : $149.1 million ) of net unrealized gains on discontinued cash flow hedges are still included in accumulated other comprehensive income. As of December 31, 2017 , we had the following interest rate derivatives outstanding: $ in thousands Counterparty Notional Maturity Date Fixed Interest Rate in Contract ING Capital Markets LLC 350,000 2/24/2018 0.95 % UBS AG 500,000 5/24/2018 1.10 % ING Capital Markets LLC 400,000 6/5/2018 0.87 % CME Central Clearing 300,000 2/5/2021 2.50 % CME Central Clearing 300,000 2/5/2021 2.69 % Wells Fargo Bank, N.A. 200,000 3/15/2021 3.14 % CME Central Clearing 500,000 5/24/2021 2.25 % Citibank, N.A. 200,000 5/25/2021 2.83 % CME Central Clearing 500,000 6/24/2021 2.44 % HSBC Bank USA, National Association 550,000 2/24/2022 2.45 % CME Central Clearing 1,000,000 6/9/2022 2.21 % CME Central Clearing 1,000,000 8/14/2022 1.87 % The Royal Bank of Scotland Plc 500,000 8/15/2023 1.98 % CME Central Clearing 600,000 8/24/2023 2.88 % HSBC Bank USA, National Association 500,000 12/15/2023 2.20 % CME Central Clearing 450,000 1/12/2024 2.10 % CME Central Clearing 450,000 1/25/2024 2.15 % CME Central Clearing 100,000 4/2/2025 2.04 % LCH Central Clearing 220,000 8/29/2027 2.12 % CME Central Clearing (1) 250,000 5/24/2028 2.78 % CME Central Clearing (1) 250,000 5/24/2028 2.39 % Total 9,120,000 2.13 % (1) Forward start date of 5/24/2018 Refer to Note 8 - "Collateral Positions" for further information regarding our collateral pledged to and received from our interest rate swap counterparties. Interest Rate Swaptions We periodically purchase interest rate swaptions to help mitigate the potential impact of increases or decreases in interest rates on the performance of a portion of our investment portfolio (referred to as “convexity risk”). The interest rate swaptions provide us the option to enter into interest rate swap agreements for a predetermined notional amount, stated term and pay and receive interest rates in the future. The premium paid for interest rate swaptions is reported as a derivative asset in our consolidated balance sheets. The premium is valued at an amount equal to the fair value of the swaption that would have the effect of closing the position adjusted for nonperformance risk, if any. The difference between the premium and the fair value of the swaption is reported in gain (loss) on derivative instruments, net in our consolidated statements of operations. If an interest rate swaption expires unexercised, the loss on the interest rate swaption would be equal to the premium paid. If we sell or exercise an interest rate swaption, the realized gain or loss on the interest rate swaption would be equal to the difference between the cash or the fair value of the underlying interest rate swap received and the premium paid. As of December 31, 2017 and December 31, 2016 , we have no outstanding interest rate swaptions. Currency Forward Contracts We use currency forward contracts to help mitigate the potential impact of changes in foreign currency exchange rates on our investments denominated in foreign currencies. Realized and unrealized gains and losses associated with the purchases or sales of currency forward contracts are recognized in gain (loss) on derivative instruments, net in our consolidated statements of operations. As of December 31, 2017 , we have $49.7 million ( December 31, 2016 : $49.0 million ) of notional amount of forward contracts denominated in Pound Sterling and $27.2 million ( December 31, 2016 : $13.3 million ) of notional amount of forward contracts denominated in Euro. Credit Derivatives Our GSE CRTs purchased prior to August 24, 2015 are accounted for as hybrid financial instruments consisting of a debt host contract and an embedded credit derivative. Embedded derivatives associated with GSE CRTs are recorded within mortgage-backed and credit risk transfer securities, at fair value, on our consolidated balance sheets. As of December 31, 2017 and 2016 , terms of the GSE CRT embedded derivatives are: $ in thousands December 31, 2017 December 31, 2016 Fair value amount 45,400 17,095 Notional amount 553,493 569,966 Maximum potential amount of future undiscounted payments 553,493 569,966 Tabular Disclosure of the Effect of Derivative Instruments on the Balance Sheet The table below presents the fair value of our derivative financial instruments, as well as their classification on our consolidated balance sheets as of December 31, 2017 and 2016 . $ in thousands Derivative Assets Derivative Liabilities As of December 31, 2017 As of December 31, 2016 As of December 31, 2017 As of December 31, 2016 Balance Sheet Fair Value Fair Value Balance Sheet Fair Value Fair Value Interest Rate Swaps Asset 6,896 3,085 Interest Rate Swaps Liability 31,548 133,833 Currency Forward Contracts — 101 Currency Forward Contracts 1,217 395 As a result of rulebook changes governing central clearing activities effective January 3, 2017, the daily variation margin payment for a centrally cleared interest rate swaps is characterized as settlement of the derivative itself rather than collateral. As a result of the rule change, cash collateral pledged on our centrally cleared interest rate swaps is settled against fair value of these swaps. Tabular Disclosure of the Effect of Derivative Instruments on the Income Statement The tables below present the effect of our credit derivatives on our consolidated statements of operations for the years ended December 31, 2017 , 2016 and 2015 . $ in thousands Year ended December 31, 2017 Derivative not designated as hedging instrument Realized gain (loss), net GSE CRT embedded derivative coupon interest Unrealized gain (loss), net Realized and unrealized credit derivative income (loss), net GSE CRT Embedded Derivatives — 23,343 28,305 51,648 $ in thousands Year ended December 31, 2016 Derivative not designated as hedging instrument Realized gain (loss), net GSE CRT embedded derivative coupon interest Unrealized gain (loss), net Realized and unrealized credit derivative income (loss), net GSE CRT Embedded Derivatives (6,017 ) 24,343 42,817 61,143 $ in thousands Year ended December 31, 2015 Derivative not designated as hedging instrument Realized gain (loss), net GSE CRT embedded derivative coupon interest Unrealized gain (loss), net Realized and unrealized credit derivative income (loss), net GSE CRT Embedded Derivatives (2,184 ) 24,822 (4,227 ) 18,411 Credit Default Swap Contract 1,044 723 (396 ) 1,371 Total (1,140 ) 25,545 (4,623 ) 19,782 The following tables summarize the effect of interest rate swaps, interest rate swaptions, TBAs, futures contracts and currency forward contracts reported in gain (loss) on derivative instruments, net on the consolidated statements of operations for the years ended December 31, 2017 , 2016 and 2015 . $ in thousands Year ended December 31, 2017 Derivative not designated as hedging instrument Realized gain (loss) on derivative instruments, net Contractual net interest expense Unrealized gain (loss), net Gain (loss) on derivative instruments, net Interest Rate Swaps 72,894 (77,076 ) 28,316 24,134 Currency Forward Contracts (5,056 ) — (923 ) (5,979 ) Total 67,838 (77,076 ) 27,393 18,155 $ in thousands Year ended December 31, 2016 Derivative not designated as hedging instrument Realized gain (loss) on derivative instruments, net Contractual net interest expense Unrealized gain (loss), net Gain (loss) on derivative instruments, net Interest Rate Swaps (69,090 ) (104,804 ) 100,503 (73,391 ) Interest Rate Swaptions (1,485 ) — 1,485 — Currency Forward Contracts 12,632 — (2,056 ) 10,576 Total (57,943 ) (104,804 ) 99,932 (62,815 ) $ in thousands Year ended December 31, 2015 Derivative Realized gain (loss) on derivative instruments, net Contractual net interest expense Unrealized gain (loss), net Gain (loss) on derivative instruments, net Interest Rate Swaps (31,881 ) (184,373 ) (554 ) (216,808 ) Interest Rate Swaptions (10,328 ) — 8,521 (1,807 ) TBAs (2,292 ) — 558 (1,734 ) Futures Contracts (943 ) — (90 ) (1,033 ) Currency Forward Contracts 1,172 — 1,162 2,334 Total (44,272 ) (184,373 ) 9,597 (219,048 ) Credit-risk-related Contingent Features We have agreements with each of our bilateral derivative counterparties. Some of those agreements contain a provision whereby if we default on any of our indebtedness, including default whereby repayment of the indebtedness has not been accelerated by the lender, we could also be declared in default on our derivative obligations. At December 31, 2017 , the fair value of derivatives in a net liability position, which includes accrued interest but excludes any adjustment for non-performance risk related to bilateral interest rate swap agreements, was $21.7 million . We have minimum collateral posting thresholds with certain of our derivative counterparties and have posted $23.7 million of Agency RMBS as of December 31, 2017 . If we had breached any of these provisions at December 31, 2017 , we could have been required to settle our obligations under the agreements at their termination value. We also have an agreement with a clearing counterparty for our interest rate swaps that includes cross default provisions. The fair value of our centrally cleared interest rate derivative contracts, which includes accrued interest and variation margin but excludes any adjustment for non-performance risk, was a net liability of $10.3 million as of December 31, 2017 . We were in compliance with all of the financial provisions of these counterparty agreements as of December 31, 2017 .

Offsetting Assets and Liabiliti

Offsetting Assets and Liabilities	12 Months Ended
	Dec. 31, 2017
Offsetting [Abstract]
Offsetting Assets and Liabilities	Offsetting Assets and Liabilities Certain of our repurchase agreements and derivative transactions are governed by underlying agreements that generally provide for a right of offset under master netting arrangements (or similar agreements), in the event of default or in the event of bankruptcy of either party to the transactions. Assets and liabilities subject to such arrangements are presented on a gross basis in the consolidated balance sheets. The following tables present information about the assets and liabilities that are subject to master netting arrangements (or similar agreements) and can potentially be offset on our consolidated balance sheets at December 31, 2017 and December 31, 2016 . As a result of rulebook changes governing central clearing activities effective January 3, 2017, the daily variation margin payment for a centrally cleared interest rate swaps is characterized as settlement of the derivative itself rather than collateral. Our derivative liability of $10.3 million at December 31, 2017 related to centrally cleared interest rate swaps is not included in the table below as a result of this change. Offsetting of Derivative Assets As of December 31, 2017 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Assets presented in the Consolidated Balance Sheets Financial Instruments Cash Collateral Received Net Amount Derivatives (1)(3) 6,896 — 6,896 — (6,896 ) — Offsetting of Derivative Liabilities, Repurchase Agreements and Secured Loans As of December 31, 2017 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Liabilities presented in the Consolidated Balance Sheets Financial Instruments (2) Cash Collateral Pledged Net Amount Derivatives (3) 22,445 — 22,445 (21,169 ) (620 ) 656 Repurchase Agreements (4) 14,080,801 — 14,080,801 (14,080,801 ) — — Secured Loans (5) 1,650,000 — 1,650,000 (1,650,000 ) — — Total 15,753,246 — 15,753,246 (15,751,970 ) (620 ) 656 Offsetting of Derivative Assets As of December 31, 2016 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Assets presented in the Consolidated Balance Sheets Financial Instruments Cash Collateral Received Net Amount Derivatives (1)(3) 3,186 — 3,186 (1,640 ) (1,546 ) — Offsetting of Derivative Liabilities and Repurchase Agreements As of December 31, 2016 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Liabilities presented in the Consolidated Balance Sheets Financial Instruments (2) Cash Collateral Pledged Net Amount Derivatives (3) 134,228 — 134,228 (45,738 ) (85,787 ) 2,703 Repurchase Agreements (4) 11,160,669 — 11,160,669 (11,160,669 ) — — Secured Loans (5) 1,650,000 — 1,650,000 (1,650,000 ) — — 12,944,897 — 12,944,897 (12,856,407 ) (85,787 ) 2,703 (1) Amounts represent derivatives in an asset position which could potentially be offset against derivatives in a liability position at December 31, 2017 and December 31, 2016 , subject to a netting arrangement. (2) Amounts represent collateral pledged that is available to be offset against liability balances associated with repurchase agreements, secured loans and derivatives. (3) The fair value of securities pledged against our derivatives was $23.7 million and $46.3 million at December 31, 2017 and December 31, 2016 , respectively. Cash collateral received on our derivatives was $7.3 million and $1.7 million at December 31, 2017 and December 31, 2016 , respectively. Cash collateral pledged by us on our derivatives was $620,000 and $86.5 million at December 31, 2017 and December 31, 2016 , respectively. As a result of rulebook changes governing central clearing activities effective January 3, 2017, cash collateral pledged on our centrally cleared interest rate swaps is settled against the fair value of these swaps and therefore excluded from the tables above at December 31, 2017 . (4) The fair value of securities pledged against our borrowing under repurchase agreements was $15.5 billion and $12.4 billion at December 31, 2017 and December 31, 2016 , respectively. (5) The fair value of securities pledged against IAS Services LLC's borrowing under secured loans was $1.9 billion and $1.9 billion at December 31, 2017 and December 31, 2016 , respectively.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments A three-level valuation hierarchy exists for disclosure of fair value measurements based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. Observable inputs reflect readily obtainable data from independent sources, while unobservable inputs reflect our market assumptions. The three levels are defined as follows: • Level 1 Inputs – Quoted prices for identical instruments in active markets. • Level 2 Inputs – Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable. • Level 3 Inputs – Instruments with primarily unobservable value drivers. The following tables present our assets and liabilities measured at fair value on a recurring basis. December 31, 2017 Fair Value Measurements Using: $ in thousands Level 1 Level 2 Level 3 NAV as a practical expedient (3) Total at Fair Value Assets: Mortgage-backed and credit risk transfer securities (1) (2) — 18,145,354 45,400 — 18,190,754 Derivative assets — 6,896 — — 6,896 Other assets (4) 3,979 — — 25,972 29,951 Total assets 3,979 18,152,250 45,400 25,972 18,227,601 Liabilities: Derivative liabilities — 32,765 — — 32,765 Total liabilities — 32,765 — — 32,765 December 31, 2016 Fair Value Measurements Using: $ in thousands Level 1 Level 2 Level 3 NAV as a practical expedient (3) Total at Fair Value Assets: Mortgage-backed and credit risk transfer securities (1) (2) — 14,964,236 17,095 — 14,981,331 Derivative assets — 3,186 — 3,186 Other assets (4) 500 — — 33,301 33,801 Total assets 500 14,967,422 17,095 33,301 15,018,318 Liabilities: Derivative liabilities — 134,228 — — 134,228 Total liabilities — 134,228 — — 134,228 (1) For more detail about the fair value of our MBS and GSE CRTs, refer to Note 4 - "Mortgage-Backed and Credit Risk Transfer Securities." (2) Our GSE CRTs purchased prior to August 24, 2015 are accounted for as hybrid financial instruments with an embedded derivative. The hybrid instruments consist of debt host contracts classified as Level 2 and embedded derivatives classified as Level 3. As of December 31, 2017 , the net embedded derivative asset position of $45.4 million includes $46.5 million of embedded derivatives in an asset position and $1.1 million of embedded derivatives in a liability position. As of December 31, 2016 , the net embedded derivative asset position of $17.1 million includes $21.0 million of embedded derivatives in an asset position and $3.9 million of embedded derivatives in a liability position. (3) Investments in unconsolidated ventures are valued using the net asset value ("NAV") as a practical expedient and are not subject to redemption, although investors may sell or transfer their interest at the approval of the general partner of the underlying funds. As of December 31, 2017 and December 31, 2016 , the weighed average remaining term of investments in unconsolidated ventures is 1.9 years and 1.3 years, respectively. (4) Includes $4.0 million and $500,000 of investments in an exchange-traded fund as of December 31, 2017 and December 31, 2016 , respectively. The following table shows a reconciliation of the beginning and ending fair value measurements of our GSE CRT embedded derivatives, which we have valued utilizing Level 3 inputs: Years Ended $ in thousands December 31, 2017 December 31, 2016 Beginning balance 17,095 (25,722 ) Sales and settlements — 6,017 Total net gains / (losses) included in net income: Realized gains/(losses), net — (6,017 ) Unrealized gains/(losses), net (1) 28,305 42,817 Ending balance 45,400 17,095 (1) Included in realized and unrealized credit derivative income (loss), net in the consolidated statements of operations are $28.3 million in net unrealized gains and $36.2 million in net unrealized gains attributable to assets still held as of December 31, 2017 and December 31, 2016 , respectively. During the year ended December 31, 2016 , we reversed $6.6 million in net unrealized gains on securities sold during the period. The following tables summarize significant unobservable inputs used in the fair value measurement of our GSE CRT embedded derivatives: Fair Value at $ in thousands December 31, 2017 Valuation Technique Unobservable Input Range Weighted Average GSE CRT Embedded Derivatives 45,400 Market Comparables, Vendor Pricing Weighted average life 2.6 - 6.8 years 4.8 years Fair Value at $ in thousands December 31, 2016 Valuation Technique Unobservable Input Range Weighted Average GSE CRT Embedded Derivatives 17,095 Market Comparables, Vendor Pricing Weighted average life 2.5 - 7.7 years 5.3 years These significant unobservable inputs change according to market conditions and security performance. We estimate the weighted average life of GSE CRTs in order to identify GSE corporate debt with a similar maturity. We obtain our weighted average life estimates from a third party provider. Although weighted average life is a significant input, changes in weighted average life may not have an explicit directional impact on the fair value measurement. The following table presents the carrying value and estimated fair value of our financial instruments that are not carried at fair value on the consolidated balance sheets at December 31, 2017 and December 31, 2016 : December 31, 2017 December 31, 2016 $ in thousands Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value Financial Assets: Commercial loans, held-for-investment 191,808 191,930 273,355 275,319 Other assets 74,250 74,250 74,250 74,250 Total 266,058 266,180 347,605 349,569 Financial Liabilities: Repurchase agreements 14,080,801 14,080,460 11,160,669 11,161,034 Secured loans 1,650,000 1,650,000 1,650,000 1,650,000 Exchangeable senior notes 143,231 143,948 397,041 400,000 Total 15,874,032 15,874,408 13,207,710 13,211,034 The following describes our methods for estimating the fair value for financial instruments. • The estimated fair value of commercial loans held-for-investment is a Level 3 fair value measurement. Subsequent to the origination or purchase, commercial loan investments are valued on monthly basis by an independent third party valuation agent using a discounted cash flow technique. • The estimated fair value of FHLBI stock, included in "Other assets," is a Level 3 fair value measurement. FHLBI stock may only be sold back to the FHLBI at its discretion at cost. As a result, the cost of the FHLBI stock approximates its fair value. • The estimated fair value of repurchase agreements is a Level 3 fair value measurement based on an expected present value technique. This method discounts future estimated cash flows using rates we determined best reflect current market interest rates that would be offered for repurchase agreements with similar characteristics and credit quality. • The estimated fair value of secured loans is a Level 3 fair value measurement. The secured loans have floating rates based on an index plus a spread and the spread is typically consistent with those demanded in the market. Accordingly, the interest rates on these secured loans are at market, and thus the carrying amount approximates fair value. • The estimated fair value of exchangeable senior notes is a Level 2 fair value measurement based on a valuation obtained from a third-party pricing service.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions We are externally managed and advised by Invesco Advisers, Inc. (our "Manager"), a wholly-owned subsidiary of Invesco Ltd. Our Manager is at all times subject to the supervision and oversight of our Board of Directors and has only such functions and authority as we delegate to it. Our Manager and its affiliates provide us with our management team, including our officers and appropriate support personnel. Each of our officers is an employee of our Manager or one of its affiliates. We do not have any employees. Our Manager is not obligated to dedicate any of its employees exclusively to us, nor is our Manager obligated to dedicate any specific portion of time to our business. During the year ended December 31, 2017 , we reimbursed our Manager $ 801,000 ( 2016 : $ 695,000 ; 2015 : $ 544,000 ) for costs of support personnel that are fully dedicated to our business. We have invested $74.4 million as of December 31, 2017 ( 2016 : $149.9 million ) in money market or mutual funds managed by affiliates of our Manager. The investments are reported as cash and cash equivalents on our consolidated balance sheets. We also pay our Manager a portion of the origination and commitment fees received from borrowers in connection with purchasing and originating commercial real estate loans. For the year ended December 31, 2017 , we did not receive any fees or pay our Manager any fees related to such transactions. For the year ended December 31, 2016 , we paid our Manager $690,000 ( 2015 : $1.3 million ) related to such transactions. Management Fee We pay our Manager a management fee equal to 1.50% of our stockholders’ equity per annum. The fee is calculated and payable quarterly in arrears. For purposes of calculating the management fee, stockholders’ equity is equal to the sum of the net proceeds from all issuances of equity securities since inception including proceeds from the issuance of operating partnership units to an affiliate of our Manager, plus retained earnings at the end of the most recently completed calendar quarter (without taking into account any non-cash equity compensation expense incurred in current or prior periods), less any amount paid to repurchase common stock since inception. Stockholder's equity excludes (i) any unrealized gains, losses or other items that do not affect realized net income (regardless of whether such items are included in other comprehensive income or loss, or in net income); (ii) cumulative net realized losses that are not attributable to permanently impaired investments and that relate to the investments for which market movement is accounted for in other comprehensive income; provided, however, that such adjustment shall not exceed cumulative unrealized net gains in other comprehensive income; (iii) one-time events pursuant to changes in U.S. GAAP; and (iv) certain non-cash items after discussions between our Manager and our independent directors and approval by a majority of our independent directors. We do not pay any management fees on our investments in unconsolidated ventures that are managed by an affiliate of our Manager. In 2016, we recorded a cumulative one-time adjustment of $2.3 million related to a prior adjustment for the accounting for premiums and discounts associated with non-Agency RMBS not of high credit quality. Expense Reimbursement We are required to reimburse our Manager for operating expenses incurred on our behalf, including directors and officers insurance, accounting services, auditing and tax services, filing fees, and miscellaneous general and administrative costs. Our reimbursement obligation is not subject to any dollar limitation. The following table summarizes the costs incurred on our behalf by our Manager for the years ended December 31, 2017 , 2016 and 2015 . Years ended December 31, $ in thousands 2017 2016 2015 Incurred costs, prepaid or expensed 5,997 6,986 6,463 Incurred costs, charged against equity as a cost of raising capital 299 — 22 Incurred costs, capitalized to other assets — 50 — Total incurred costs, originally paid by our Manager 6,296 7,036 6,485 Termination Fee If we terminate our management agreement, we owe our Manager a termination fee equal to three times the sum of our average annual management fee during the 24 -month period before termination, calculated as of the end of the most recently completed fiscal quarter.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Preferred Stock Holders of our Series A Preferred Stock are entitled to receive dividends at an annual rate of 7.75% of the liquidation preference of $25.00 per share or $1.9375 per share per annum. These dividends are cumulative and payable quarterly in arrears. Holders of our Series B Preferred Stock are entitled to receive dividends at an annual rate of 7.75% of the liquidation preference of $25.00 per share or $1.9375 per share per annum until December 27, 2024. After December 27, 2024, holders are entitled to receive dividends at a floating rate equal to three-month LIBOR plus a spread of 5.18% of the $25.00 liquidation preference per annum. These dividends are cumulative and payable quarterly in arrears. In August 2017, we completed a public offering of 11,500,000 shares of 7.50% Fixed-to-Floating Series C Cumulative Redeemable Preferred Stock (the "Series C Preferred Stock") at the price of $25.00 per share. Total proceeds were $287.5 million before issuance costs of $9.4 million . Holders of our Series C Preferred Stock are entitled to receive dividends at an annual rate of 7.50% of the liquidation preference of $25.00 per share or $1.875 per share per annum until September 27, 2027. After September 27, 2027, holders are entitled to receive dividends at a floating rate equal to three-month LIBOR plus a spread of 5.289% of the $25.00 liquidation preference per annum. Dividends are cumulative and payable quarterly in arrears, commencing with the first dividend payment date on December 27, 2017. As of July 27, 2017, we have the option to redeem shares of our Series A Preferred Stock for $25.00 per share, plus any accumulated and unpaid dividends through the date of redemption. We have the option to redeem shares of Series B Preferred Stock after December 27, 2024 and shares of Series C Preferred Stock after September 27, 2027 for $25.00 per share, plus any accumulated and unpaid dividends through the date of the redemption. Shares of Series B and Series C Preferred Stock are not redeemable, convertible into or exchangeable for any other property or any other securities of the Company prior to those times, except under circumstances intended to preserve our qualification as a REIT or upon the occurrence of a change in control. Common Stock Prior to April 1, 2016, we had a dividend reinvestment and stock purchase plan (the “DRSPP”) that allowed participating stockholders to purchase shares of common stock directly from us. DRSPP participants also had the ability to automatically reinvest all or a portion of their dividends in exchange for additional shares of common stock. During the year ended December 31, 2016 , we issued 3,201 ( 2015 : 12,945 ) shares of common stock at an average price of $11.08 (2015: $14.75 ) under the DRSPP. We received total proceeds of approximately $35,000 ( 2015 : $191,000 ). Effective April 1, 2016, we terminated our DRSPP and replaced the DSRPP program with a direct stock purchase plan and dividend reinvestment program administered by an affiliate of our transfer agent. In December 2017, we entered into an equity distribution agreement with a placement agent under which we may sell up to 17,000,000 shares of our common stock from time to time in at-the-market or privately negotiated transactions. These shares will be registered with the SEC under our automatic shelf registration statement (as amended and/or supplemented). As of December 31, 2017 , we have not sold any shares of common stock under the equity distribution agreement. Securities Convertible into Shares of Common Stock The non-controlling interest holder of our Operating Partnership, a wholly-owned Invesco subsidiary, has the right to cause the Operating Partnership to redeem their operating partnership units ("OP Units") for cash equal to the market value of an equivalent number of shares of common stock, or at our option, we may purchase their OP Units by issuing one share of common stock for each OP Unit redeemed. Upon completion of our initial public offering, we entered into a registration rights agreement with Invesco. Under the registration rights agreement, we have granted Invesco (i) unlimited demand registration rights to have the common stock and OP Units owned by Invesco and any shares of common stock granted to our Manager registered for resale and (ii) in certain circumstances, the right to “piggy-back” these shares in registration statements we might file in connection with any future public offering so long as we retain our Manager under the management agreement. Our Exchangeable Senior Notes are also convertible into shares of common stock. On March 12, 2013, we entered into a registration rights agreement with the initial purchasers of our Exchangeable Senior Notes. Under the registration rights agreement, we agreed to file a prospectus supplement to our automatic shelf registration statement if requested by noteholders to add such noteholders as selling securityholders. If our automatic shelf registration ceases to be effective, additional interest will accrue on the Notes, subject to certain exceptions. Refer to Note 7 - "Borrowings" for further discussion of the Exchangeable Senior Notes. We have adopted an equity incentive plan which allows us to grant securities convertible into our common stock to our independent directors and employees of our Manager and its affiliates. Refer to "Share Based Compensation" below for further discussion of our equity incentive plan. Share Repurchase Program In December 2011, our board of directors approved a share repurchase program with no stated expiration date. We did not purchase any shares during the year ended December 31, 2017 . During the year ended December 31, 2016 , we repurchased and concurrently retired 2,063,451 shares of our common stock at a weighted average repurchase price of $12.12 per share for a net cost of $25.0 million , including acquisition expenses. As of December 31, 2017 , we had authority to purchase 18,239,082 additional shares of our common stock through the share repurchase program. Share-Based Compensation We established the 2009 Equity Incentive Plan for grants of common stock and other equity based awards to our independent directors and officers and employees of our Manager and its affiliates (the “Incentive Plan”). Under the Incentive Plan, a total of 1,000,000 shares of common stock are authorized for issuance. Unless terminated earlier, the Incentive Plan will terminate in 2019 , but will continue to govern the unexpired awards. As of December 31, 2017 , 792,520 shares of common stock remain available for future issuance under the Incentive Plan. We recognized compensation expense of approximately $453,000 ( 2016 : $340,000 ; 2015 : $340,000 ) related to awards to our independent directors for the year ended December 31, 2017 . During the year ended December 31, 2017 , we issued 25,006 shares ( 2016 : 25,068 shares; 2015 : 23,776 shares) of common stock under the Incentive Plan to our independent directors. The fair market value of the shares granted was determined by the closing stock market price on the date of the grant. The grants vested immediately. We recognized compensation expense of approximately $138,000 ( 2016 : $100,000 ; 2015 : $219,000 ) for the year ended December 31, 2017 related to restricted stock units awarded to employees of our Manager and its affiliates which is reimbursed by our Manager under the management agreement. At December 31, 2017 , there was approximately $239,000 of total unrecognized compensation cost related to restricted stock unit awards that is expected to be recognized over a period of up to 39 months, with a weighted-average remaining vesting period of 15 months. The following table summarizes the activity related to restricted stock units awarded to employees of our Manager and its affiliates for the year ended December 31, 2017 . Year Ended December 31, 2017 Restricted Stock Units Weighted Average Grant Date Fair Value (1) Unvested at the beginning of the year 18,807 $ 14.37 Shares granted during the year 8,115 15.55 Shares vested during the year (7,095 ) 15.78 Unvested at the end of the year 19,827 $ 14.35 (1) The grant date fair value of restricted stock unit awards is based on the closing market price of our common stock at the grant date. Accumulated Other Comprehensive Income The following tables present the components of total other comprehensive income (loss), net and accumulated other comprehensive income ("AOCI") at December 31, 2017 and December 31, 2016 , respectively. The tables exclude gains and losses on MBS and GSE CRTs that are accounted for under the fair value option. December 31, 2017 $ in thousands Equity method investments Available-for-sale securities Derivatives and hedging Total Total other comprehensive income (loss), net: Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net — (9,885 ) — (9,885 ) Reclassification of unrealized (gain) loss on sale of mortgage-backed and credit risk transfer securities to gain (loss) on investments, net — 1,508 — 1,508 Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense — — (25,544 ) (25,544 ) Currency translation adjustments on investment in unconsolidated venture 863 — — 863 Total other comprehensive income (loss), net 863 (8,377 ) (25,544 ) (33,058 ) AOCI balance at beginning of period 95 144,458 149,115 293,668 Other comprehensive income/(loss), net 863 (8,377 ) (25,544 ) (33,058 ) Other comprehensive income/(loss) attributable to non-controlling interest (11 ) 106 323 418 Rebalancing of ownership percentage of non-controlling interest — 1 — 1 AOCI balance at end of period 947 136,188 123,894 261,029 December 31, 2016 $ in thousands Equity method investments Available-for-sale securities Derivatives and hedging Total Total other comprehensive income (loss), net: Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net — (37,632 ) — (37,632 ) Reclassification of unrealized (gain) loss on sale of mortgage-backed and credit risk transfer securities to gain (loss) on investments, net — 6,134 — 6,134 Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense — — 5,154 5,154 Currency translation adjustments on investment in unconsolidated venture 128 — — 128 Total other comprehensive income (loss), net 128 (31,498 ) 5,154 (26,216 ) AOCI balance at beginning of period (32 ) 170,383 148,273 318,624 Other comprehensive income/(loss), net 128 (31,498 ) 5,154 (26,216 ) Other comprehensive income/(loss) attributable to non-controlling interest (1 ) 412 (63 ) 348 Rebalancing of ownership percentage of non-controlling interest — 5,161 (4,249 ) 912 AOCI balance at end of period 95 144,458 149,115 293,668 Effective December 31, 2013, we voluntarily discontinued cash flow hedge accounting for our interest rate swaps to gain greater flexibility in managing interest rate exposures. Amounts recorded in AOCI before we discontinued cash flow hedge accounting for our interest rate swaps are reclassified to interest expense on repurchase agreements on the consolidated statements of operations as interest is accrued and paid on the related repurchase agreements over the remaining original life of the interest rate swap agreements. Dividends The following table sets forth the dividends declared per share of our common stock. Date Declared Dividends Declared Per Share Amount Date of Payment 2017 December 14, 2017 $ 0.42 January 26, 2018 September 14, 2017 $ 0.41 October 26, 2017 June 15, 2017 $ 0.40 July 26, 2017 March 15, 2017 $ 0.40 April 26, 2017 2016 December 15, 2016 $ 0.40 January 26, 2017 September 14, 2016 $ 0.40 October 26, 2016 June 15, 2016 $ 0.40 July 26, 2016 March 15, 2016 $ 0.40 April 26, 2016 The following table sets forth the dividends declared per share of our Series A Preferred Stock. Date Declared Dividends Declared Per Share Amount Date of Payment 2017 December 14, 2017 $ 0.4844 January 25, 2018 September 14, 2017 $ 0.4844 October 25, 2017 June 15, 2017 $ 0.4844 July 25, 2017 March 15, 2017 $ 0.4844 April 25, 2017 2016 December 15, 2016 $ 0.4844 January 25, 2017 September 14, 2016 $ 0.4844 October 25, 2016 June 15, 2016 $ 0.4844 July 25, 2016 March 15, 2016 $ 0.4844 April 25, 2016 The following table sets forth the dividends declared per share of our Series B Preferred Stock. Date Declared Dividends Declared Per Share Amount Date of Payment 2017 September 14, 2017 $ 0.4844 December 27, 2017 June 15, 2017 $ 0.4844 September 27, 2017 March 15, 2017 $ 0.4844 June 27, 2017 2016 December 15, 2016 $ 0.4844 March 27, 2017 September 14, 2016 $ 0.4844 December 27, 2016 June 15, 2016 $ 0.4844 September 27, 2016 March 15, 2016 $ 0.4844 June 27, 2016 On September 14, 2017, we declared a dividend on Series C Preferred Stock of $ 0.68229 per share that was paid on December 27, 2017 for the period from the date of issuance, August 16, 2017, to but not including the dividend payment date, December 27, 2017. For the year ended December 31, 2017 , we reduced net income attributable to common stockholders by approximately $373,000 to account for accumulated but unpaid dividends for the period from December 27, 2017 to December 31, 2017 on our Series B and Series C Preferred Stock. The following table sets forth the dividends declared per share of our preferred and common stock and their related tax characterization for the fiscal tax years ended December 31, 2017 and 2016 . Tax Characterization of Dividends Fiscal Tax Year Dividends Declared Ordinary Dividends Capital Gain Distribution Carry Forward Series A Preferred Stock Dividends Fiscal tax year 2017 (1) 1.937600 1.937600 — — Fiscal tax year 2016 (2) 1.937600 1.937600 — — Series B Preferred Stock Dividends Fiscal tax year 2017 1.937600 1.937600 — — Fiscal tax year 2016 (3) 1.937600 1.937600 — — Series C Preferred Stock Dividends Fiscal tax year 2017 0.682290 0.682290 — — Common Stock Dividends Fiscal tax year 2017 1.630000 1.480040 — 0.149960 Fiscal tax year 2016 (4) 1.600000 1.857840 — — (1) Excludes preferred stock dividend of $0.4844 per share declared on December 14, 2017 having a record date of January 1, 2018, which for federal income tax purposes is a fiscal tax year 2018 dividend. (2) Excludes preferred stock dividend of $0.4844 per share declared on December 15, 2016 having a record date of January 1, 2017, which for federal income tax purposes is a fiscal tax year 2017 dividend. (3) Excludes preferred stock dividend of $0.4844 per share declared on December 15, 2016 having a record date of March 5, 2017, which for federal income tax purposes is a fiscal tax year 2017 dividend. (4) Ordinary dividends include $0.257840 of spillover dividend carried-forward from fiscal tax year 2015.

Earnings per Common Share

Earnings per Common Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings per Common Share	Earnings per Common Share Earnings per share for the years ended December 31, 2017 , 2016 and 2015 is computed as follows: $ and share amounts in thousands Years Ended December 31, 2017 2016 2015 Numerator (Income) Basic Earnings: Net income (loss) available to common stockholders 320,527 231,547 89,847 Effect of dilutive securities: Income allocated to exchangeable senior notes 13,340 22,467 — Income (loss) allocated to non-controlling interest 4,450 3,287 1,344 Dilutive net income (loss) available to stockholders 338,317 257,301 91,191 Denominator (Weighted Average Shares) Basic Earnings: Shares available to common stockholders 111,610 111,973 121,378 Effect of dilutive securities: Restricted stock awards 20 20 41 Non-controlling interest OP Units 1,425 1,425 1,425 Exchangeable senior notes 9,986 16,836 — Dilutive Shares 123,041 130,254 122,844 Earnings (loss) per share: Net income (loss) attributable to common stockholders Basic 2.87 2.07 0.74 Diluted 2.75 1.98 0.74 The following potential common shares were excluded from diluted earnings per common share for the year ended December 31, 2015 as the effect would be anti-dilutive: 16,835,720 for the exchangeable senior notes.

Non-controlling Interest - Oper

Non-controlling Interest - Operating Partnership	12 Months Ended
	Dec. 31, 2017
Noncontrolling Interest [Abstract]
Non-controlling Interest - Operating Partnership	Non-controlling Interest – Operating Partnership Non-controlling interest represents the aggregate ownership interest of a wholly-owned Invesco subsidiary in our Operating Partnership. The ownership percentage is determined by dividing the number of OP Units held by the Unit Holders by the total number of dilutive shares of common stock. The issuance or repurchase of common stock (“Share” or “Shares”) or OP Units changes the percentage ownership of both the Unit Holders and the common stockholders. Since an OP unit is generally redeemable for cash or Shares at our option, it is deemed to be a Share equivalent. Therefore, such transactions are treated as capital transactions and result in a reallocation between stockholders’ equity and non-controlling interest in the accompanying consolidated balance sheets. As of December 31, 2017 and December 31, 2016 , non-controlling interest related to the outstanding 1,425,000 OP Units represented a 1.3% interest in the Operating Partnership. During the third quarter of 2017, we recorded a cumulative out-of-period adjustment to rebalance equity in our Operating Partnership. The effect of the entry was to increase additional paid-in capital by $3.6 million and decrease non-controlling interest by $3.6 million . The adjustment did not have any impact on our consolidated statement of operations. Income allocated to the non-controlling interest is based on the Unit Holders’ ownership percentage of the Operating Partnership. The following table presents the net income (loss) allocated and distributions paid to the Operating Partnership non-controlling interest for the years ended December 31, 2017 , 2016 and 2015 . Years ended December 31, $ in thousands 2017 2016 2015 Net income (loss) allocated 4,450 3,287 1,344 Distributions paid 2,294 2,280 2,494 As of December 31, 2017 , distributions payable to the non-controlling interest were approximately $598,500 ( 2016 : $570,000 ).

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Contingencies and Contingencies	Commitments and Contingencies Commitments and contingencies may arise in the ordinary course of business. Our material off balance sheet commitments as of December 31, 2017 are discussed below. As discussed in Note 6 - "Other Assets", we have invested in unconsolidated ventures that are sponsored by an affiliate of our Manager. The unconsolidated ventures are structured as partnerships, and we invest in the partnerships as a limited partner. The entities are structured such that capital commitments are to be drawn down over the life of the partnership as investment opportunities are identified. At December 31, 2017 , our undrawn capital and purchase commitments were $10.2 million ( 2016 : $15.5 million ). As discussed in Note 5 - “Commercial Loans Held-for-Investment”, we purchase and originate commercial loans. As of December 31, 2017 , we have unfunded commitments on commercial loans held-for-investment of $4.8 million ( 2016 : $9.7 million ). We have entered into agreements with financial institutions to guarantee certain obligations of our subsidiaries. We would be required to perform under these guarantees in the event of certain defaults. We have not had prior claims or losses under these contracts and expect the risk of loss to be remote.

Summarized Quarterly Results of

Summarized Quarterly Results of Operations (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Summarized Quarterly Results of Operations (Unaudited)	Summarized Quarterly Results of Operations (Unaudited) The following is a presentation of selected unaudited results of operations for the quarters ended. $ in thousands except share amounts Q4 17 Q3 17 Q2 17 Q1 17 Q4 16 Q3 16 Q2 16 Q1 16 Interest Income Mortgage-backed and credit risk transfer securities 147,509 134,138 121,027 118,873 108,871 112,467 112,860 122,246 Commercial loans 5,472 6,251 6,021 5,764 5,718 5,680 5,947 4,893 Total interest income 152,981 140,389 127,048 124,637 114,589 118,147 118,807 127,139 Interest Expense Repurchase agreements 51,955 45,907 36,072 29,947 26,048 24,892 31,260 41,800 Secured loans 5,878 5,544 4,535 3,413 2,738 2,746 2,688 2,715 Exchangeable senior notes 2,104 2,724 3,504 5,008 5,620 5,620 5,614 5,613 Total interest expense 59,937 54,175 44,111 38,368 34,406 33,258 39,562 50,128 Net interest income 93,044 86,214 82,937 86,269 80,183 84,889 79,245 77,011 Other income (loss) Gain (loss) on investments, net (17,153 ) (11,873 ) 11,175 (1,853 ) (23,402 ) (7,155 ) 1,414 11,601 Equity in earnings of unconsolidated ventures (47 ) 408 (154 ) (1,534 ) 400 729 202 1,061 Gain (loss) on derivative instruments, net 64,251 1,955 (53,513 ) 5,462 230,713 35,378 (90,363 ) (238,543 ) Realized and unrealized credit derivative income (loss), net 13,220 (2,930 ) 21,403 19,955 3,579 31,926 17,228 8,410 Net loss on extinguishment of debt (233 ) (1,344 ) (526 ) (4,711 ) — — — — Other investment income (loss), net 1,206 2,313 2,533 1,329 (1,385 ) (554 ) (2,745 ) (318 ) Total other income (loss) 61,244 (11,471 ) (19,082 ) 18,648 209,905 60,324 (74,264 ) (217,789 ) Expenses 11,972 11,254 10,635 10,885 10,745 8,555 10,957 11,549 Net income (loss) 142,316 63,489 53,220 94,032 279,343 136,658 (5,976 ) (152,327 ) Net income (loss) attributable to non-controlling interest 1,794 800 670 1,186 3,522 1,723 (75 ) (1,883 ) Net income (loss) attributable to Invesco Mortgage Capital Inc. 140,522 62,689 52,550 92,846 275,821 134,935 (5,901 ) (150,444 ) Dividends to preferred stockholders 3,086 13,562 5,716 5,716 5,716 5,716 5,716 5,716 Net income (loss) attributable to common stockholders 137,436 49,127 46,834 87,130 270,105 129,219 (11,617 ) (156,160 ) Earnings (loss) per share: Net income (loss) attributable to common stockholders Basic 1.23 0.44 0.42 0.78 2.42 1.16 (0.10 ) (1.38 ) Diluted 1.18 0.43 0.41 0.73 2.15 1.05 (0.10 ) (1.38 )

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events We have reviewed subsequent events occurring through the date that these consolidated financial statements were issued, and determined that no subsequent events occurred that would require accrual or additional disclosure.

Schedule IV Mortgage Loans on R

Schedule IV Mortgage Loans on Real Estate	12 Months Ended
	Dec. 31, 2017
Mortgage Loans on Real Estate [Abstract]
Schedule IV Mortgage Loans on Real Estate	INVESCO MORTGAGE CAPITAL INC. AND SUBSIDIARIES Schedule IV Mortgage Loans on Real Estate As of December 31, 2017 $ in thousands Asset Type Property Type Location Interest Rate Maturity Date (1) Periodic Payment Terms (2) Prior Liens Face Amount of Mortgages Carrying Amount of Mortgages Principal Amount of Loans Subject to Delinquent Principal or Interest Mezzanine Loan Hotel FL L+7.23% 7/1/2018 I — 21,000 20,990 — Mezzanine Loan Office AZ L+6.96% 8/1/2018 I — 33,647 33,628 — Mezzanine Loan Hotel International 7.50 % 12/1/2018 I — 46,668 46,621 — Mezzanine Loan Retail/Mixed Use FL L+7.25% 2/1/2020 I — 28,000 28,000 — Mezzanine Loan Hotel TX L+8.50% 2/28/2021 I — 25,000 25,000 — Mezzanine Loan Multifamily FL L+7.50% 2/7/2018 I — 10,000 9,994 — Mezzanine Loan Multifamily TX L+7.50% 2/7/2018 I — 7,000 6,996 — Mezzanine Loan Office CA L+7.65% 3/31/2019 I — 20,579 20,579 — 191,894 191,808 (3) — (1) Based on the contractual maturity date. Certain loans may contain either an option to repay or an option to extend beyond their contractual maturity dates as specified in the respective loan agreements. (2) Interest ("I") only until stated maturity of the loan. (3) The aggregate cost for federal income tax purposes is $191.8 million. Reconciliation of Carrying Value of Mortgage Loans on Real Estate: 2017 2016 2015 Beginning balance 273,355 209,062 3,510,759 Additions: Originations and purchases of new loans 4,799 87,474 530,399 Premium (discount) on new loans — (272 ) (131 ) Amortization of commercial loan origination fees and premium (discount) 337 302 (6,204 ) Deductions: Collection of principal 90,713 15,000 642,361 Reduction in provision for loan losses — — (213 ) Loss on foreign currency revaluation (4,030 ) 8,211 1,951 Deconsolidation of VIEs — — 3,181,662 Ending balance 191,808 273,355 209,062

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation In the opinion of management, the consolidated financial statements reflect all adjustments, consisting of normal recurring accruals, which are necessary for a fair statement of our financial condition and results of operations for the periods presented. All significant intercompany transactions, balances, revenues and expenses are eliminated upon consolidation. Our consolidated financial statements have been prepared in accordance with U.S. GAAP and consolidate the financial statements of the Company and our controlled subsidiaries. During the period from January 1, 2015 through December 9, 2015, the consolidated financial statements also include the results of operations of certain residential loan securitization trusts (the "Residential Securitizations") that meet the definition of a variable interest entity ("VIE"). On December 9, 2015, we completed the sale of certain beneficial interests in the Residential Securitizations and deconsolidated the Residential Securitizations. Refer to Note 3 - "Variable Interest Entities" for additional information regarding the impact of consolidation and deconsolidation of the Residential Securitizations.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and accompanying notes. Examples of estimates include, but are not limited to, estimates of the fair values of financial instruments, interest income on mortgage-backed and credit risk transfer securities, provision for loan losses and other-than-temporary impairment charges. Actual results may differ from those estimates.
Translation of Foreign Currencies	Translation of Foreign Currencies The functional currency of the Company and its subsidiaries is U.S. dollars. Transactions in foreign currencies are recorded at the rates of exchange prevailing on the date of the transactions. At each balance sheet date, monetary assets and liabilities that are denominated in foreign currencies are remeasured at the rates prevailing at the balance sheet date. Gains and losses arising on revaluation are included in other investment income (loss), net on the consolidated statements of operations. During the years ended December 31, 2017 , 2016 and 2015 , we incurred foreign currency gains of $4.1 million , $8.2 million of losses and $1.9 million of losses, respectively, primarily related to the revaluation of our commercial loan investments denominated in Pound Sterling. Our reporting currency is U.S. dollars. Upon consolidation, the assets and liabilities of our investment in an unconsolidated venture whose functional currency is the Euro is translated to U.S. dollars using the period-end exchange rates. Equity accounts are translated at historical rates, except for the change in retained earnings during the year, which is the result of the income statement translation process. Revenue and expense accounts are translated using the weighted average exchange rate during the period. The cumulative translation adjustments associated with the investment in the unconsolidated venture are recorded in accumulated other comprehensive income (loss), a component of consolidated stockholders’ equity. We generally hedge interest rate and foreign currency exposure with derivative financial instruments. Refer to Note 9 - "Derivatives and Hedging Activities" for further information.
Fair Value Measurements	Fair Value Measurements We report our mortgage-backed and credit risk transfer securities and derivative assets and liabilities at fair value as determined by an independent pricing service. We generally obtain one price per instrument from our primary pricing service. If the primary pricing service cannot provide a price, we will seek a value from other pricing services. The pricing service uses two types of valuation approaches to determine the valuation of our various mortgage-backed and credit risk transfer securities: a market approach, which uses observable prices and other relevant information that is generated by market transactions involving identical or comparable assets or liabilities; and an income approach, which uses valuation techniques to convert future amounts to a single, discounted present value amount. In instances where sufficient market activity may not exist, the pricing service may utilize proprietary valuation models that may consider market transactions in comparable securities and the various relationships between securities in determining fair value and/or market characteristics to estimate relevant cash flows, which are then discounted to calculate the fair values. Observable inputs may include a combination of benchmark yields, executed trades, broker/dealer quotes, issuer spreads, bids, offers and benchmark securities. In addition, the valuation models utilized by pricing services may consider additional pool level information such as prepayment speeds, default frequencies and default severities, if applicable. We and the pricing service continuously monitor market indicators and economic events to determine whether they may have an impact on our valuations. The pricing service values interest rate swaps and interest rate swaptions under the income approach using valuation models. The significant inputs in these models are readily available in public markets or can be derived from observable market transactions for substantially the full terms of the contracts. The pricing service values U.S. Treasury futures, currency forward contracts and to-be-announced securities (“TBAs”) under the market approach through the use of quoted market prices available in an active market. Overrides of prices from pricing services are rare in the current market environment for the assets we hold. Examples of instances that would cause an override include if we recently traded the same security or there is an indication of market activity that would cause the pricing service price to no longer be indicative of fair value. In the rare instance where a price is adjusted, we have a control process to monitor the reason for such adjustment. To gain comfort that pricing service prices are representative of current market information, we compare the transaction prices of security purchases and sales to the valuation levels provided by the pricing services. Price differences exceeding pre-defined tolerance levels are identified and investigated and may be challenged. Trends are monitored over time and if there are indications that the valuations are not comparable to market activity, the pricing services are asked to provide detailed information regarding their methodology and inputs. Transparency tools are also available from the pricing services which help us understand data points and/or market inputs used for pricing securities. We also review daily price movements for interest rate swaps, interest rate swaptions, U.S. Treasury futures, currency forward contracts and TBAs. Price movements exceeding pre-defined tolerance levels are investigated using an alternate price from another pricing service as well as available market information. Based on our findings, the primary pricing service may be challenged, or in rare cases, overridden with an alternate pricing source. In addition, we perform due diligence procedures on all pricing services on at least an annual basis. A questionnaire is sent to pricing services which requests information such as changes in methodologies, business recovery preparedness, internal controls and confirmation that evaluations are generated based on market data. Physical visits are also made to each pricing service's office. As described in Note 11 - "Fair Value of Financial Instruments," we evaluate the source used to fair value our assets and liabilities and make a determination on its categorization within the fair value hierarchy. If the price of a security is obtained from quoted prices for identical instruments in active markets, the security is classified as a level 1 security. If the price of a security is obtained from quoted prices for similar instruments or model-derived valuations whose inputs are observable, the security is classified as a level 2 security. If the inputs appear to be unobservable, the security would be classified as a level 3 security. Transfers between levels, if any, are determined at the end of the reporting period.
Mortgage-Backed and Credit Risk Transfer Securities	Mortgage-Backed and Credit Risk Transfer Securities All of our mortgage-backed securities ("MBS") and GSE CRTs are reported at fair value. Fair value is determined by obtaining valuations from an independent source. If the fair value of a security is not available from a third-party pricing service, or such data appears unreliable, we may estimate the fair value of the security using a variety of methods including other pricing services, discounted cash flow analysis, matrix pricing, option adjusted spread models and other fundamental analysis of observable market factors. We record our purchases of MBS and GSE CRTs on the trade date. Although we generally intend to hold most of our MBS and GSE CRTs until maturity, we may sell any of its mortgage-backed and credit risk transfer securities as part of our overall management of our investment portfolio. We have elected the fair value option for all of our MBS purchased on or after September 1, 2016. Prior to September 1, 2016, we had also elected the fair value option for our RMBS interest-only securities (“RMBS IOs”). RMBS IOs are hybrid financial instruments that contain embedded derivatives. Under the fair value option, changes in fair value are recognized in our consolidated statements of operations. In our view, this election more appropriately reflects the results of our operations because MBS fair value changes are accounted for in the same manner as fair value changes in economic hedging instruments. Except for RMBS IOs, MBS purchased prior to September 1, 2016 are classified as available-for-sale securities. Unrealized gains or losses on available-for-sale securities are recorded in accumulated other comprehensive income, a separate component of stockholders' equity, until sale or disposition of the investment. Upon sale or disposition, the cumulative gain or loss previously reported in stockholders' equity is recognized in income. Realized gains and losses from sales of MBS are determined based upon the specific identification method. We have elected the fair value option for GSE CRTs purchased on or after August 24, 2015. GSE CRTs are hybrid financial instruments that contain embedded derivatives. Coupon payments on the securities are based on LIBOR, and principal payments are based on prepayments, losses and defined credit events in a reference pool of mortgage loans that collateralize Agency RMBS. We elected the fair value option for these securities due to the complexities associated with bifurcation of GSE CRTs into a debt host contract and an embedded derivative. Under the fair value option, changes in fair value for GSE CRTs are recognized in our consolidated statements of operations. GSE CRTs purchased prior to August 24, 2015 are also reported at fair value but are accounted for as hybrid financial instruments consisting of a debt host contract and an embedded derivative. Unrealized gains or losses arising from changes in fair value of the debt host contract, excluding other-than-temporary impairment, are recognized in accumulated other comprehensive income, a separate component of stockholders’ equity, until sale or disposition of the investment. Upon sale or disposition of the debt host contract, the cumulative gain or loss previously reported in stockholders’ equity is recognized in income. Realized gains and losses from sales of GSE CRTs are determined based upon the specific identification method. Realized and unrealized gains or losses arising from changes in fair value of the embedded derivative are recognized in realized and unrealized credit derivative income (loss), net in our consolidated statements of operations. Our interest income recognition policies for MBS and GSE CRTs is described below in the Interest Income Recognition section of this Note 2 to our consolidated financial statements. We consider our portfolio of Agency RMBS to be of high credit quality under applicable accounting guidance. For CMBS, non-Agency RMBS and GSE CRTs, we do not rely on ratings from third party agencies to determine the credit quality of the investment. We use internal models that analyze the loans underlying each security and evaluates factors including, but not limited to, delinquency status, loan-to-value ratios, borrower credit scores, occupancy status and geographic concentration to estimate the expected future cash flows. We place reliance on these internal models in determining credit quality. While CMBS, non-Agency RMBS and GSE CRTs with expected future losses would generally be purchased at a discount to par, the potential for a significant adverse change in expected cash flows remains. We therefore evaluate each security in an unrealized loss position for other-than-temporary impairment at least quarterly. The determination of whether a security is other-than-temporarily impaired involves judgments and assumptions based on subjective and objective factors. Consideration is given to (i) our intent to sell the security and whether it is more likely than not that we will be required to sell the security before recovery of its amortized cost and (ii) the financial condition and near-term prospects of recovery in fair value of the security. This includes a determination of estimated future cash flows through an evaluation of the characteristics of the underlying loans and the structural features of the investment. Underlying loan characteristics reviewed include, but are not limited to, delinquency status, loan-to-value ratios, borrower credit scores, occupancy status and geographic concentration. We recognize in earnings and reflect as a reduction in the cost basis of the security the amount of any other-than-temporary impairment related to credit losses or impairments on securities that we intend to sell or for which it is more likely than not that we will need to sell before recoveries. The amount of the other-than-temporary impairment on debt securities related to other factors is recorded consistent with changes in the fair value of all other available-for-sale securities as a component of consolidated stockholders’ equity in other comprehensive income or loss with no change to the cost basis of the security.
Commercial Loans Held-For-Investment	Commercial Loans Held-For-Investment We carry commercial loans held-for-investment at amortized cost, net of any provision for loan losses. An individual loan is considered impaired when it is deemed probable that the Company will not be able to recover its investment and any other anticipated future payments. We generally consider the following factors in evaluating whether a commercial loan is impaired: • Loan-to-value ratios; • The most recent financial information available for each loan and associated properties, including net operating income, debt service coverage ratios, occupancy rates, rent rolls, as well as any other factors we consider relevant, including, but not limited to, specific loan trigger events that would indicate an adverse change in expected cash flows or payment delinquency; • Economic trends, both macroeconomic as well as those directly affecting the properties associated with the loans, and the supply and demand trends in the market in which the subject property is located; and • The loan sponsor or borrowing entity’s ability to ensure that properties associated with the loan are managed and operated sufficiently. When an individual commercial loan is deemed to be impaired, we record a provision to reduce the carrying value of the loan to the current present value of expected future cash flows discounted at the loan’s effective interest rate or if the loan is collateral dependent, we reduce the carrying value to the estimated fair value of the collateral, with a corresponding charge to provision for loan losses on our consolidated statements of operations.
Interest Income Recognition	Interest Income Recognition Mortgage-Backed Securities Interest income on MBS is accrued based on the outstanding principal or notional balance of the securities and their contractual terms. Premiums or discounts are amortized or accreted into interest income over the life of the investment using the effective interest method. Interest income on our MBS where we may not recover substantially all of our initial investment is based on estimated future cash flows. We estimate future expected cash flows at the time of purchase and determine the effective interest rate based on these estimated cash flows and our purchase price. Over the life of the investments, we update these estimated future cash flows and compute a revised yield based on the current amortized cost of the investment. In estimating these future cash flows, there are a number of assumptions that are subject to uncertainties and contingencies, including but not limited to the rate and timing of principal payments (prepayments, repurchases, defaults and liquidations), the pass through or coupon rate, and interest rate fluctuations. These uncertainties and contingencies are difficult to predict and are subject to future events that may impact our estimate and our interest income. Changes in our original or most recent cash flow projections may result in a prospective change in interest income recognized on these securities, or the amortized cost of these securities. For non-Agency RMBS not of high credit quality, when actual cash flows vary from expected cash flows, the difference is recorded as an adjustment to the amortized cost of the security and the security's yield is revised prospectively. For Agency RMBS that cannot be prepaid in such a way that we would not recover substantially all of our initial investment, interest income recognition is based on contractual cash flows. We do not estimate prepayments in applying the effective interest method. Credit Risk Transfer Securities Interest income on GSE CRTs purchased prior to August 24, 2015 is accrued based on the coupon rate of the debt host contract which reflects the credit risk of GSE unsecured senior debt with a similar maturity. Premiums or discounts associated with the purchase of credit risk transfer securities are amortized or accreted into interest income over the life of the debt host contract using the effective interest method. The difference between the coupon rate on the hybrid instrument and the coupon rate on the GSE CRT debt host contract is considered premium income associated with the embedded derivative and is recorded in realized and unrealized credit derivative income (loss), net in our consolidated statements of operations. Interest income on GSE CRTs purchased on or after August 24, 2015 is based on estimated future cash flows. Residential Loans Prior to the deconsolidation of the Residential Securitizations, we recognized interest income from residential loans held by our consolidated VIEs on an accrual basis and amortized the related premiums and discounts into interest income using the effective interest method over the weighted average life of these loans. In estimating the weighted average life of these loans, there were a number of assumptions that were subject to estimation, including the rate and timing of principal payments, defaults, loss severity given default and other factors. Coupon interest was recognized as revenue when earned and deemed collectible or until a loan became more than 90 days past due, at which point the loan was placed on nonaccrual status. Interest previously accrued for loans that had been placed on non-accrual status was reversed against interest income in the period the loan was placed in nonaccrual status. Residential loans delinquent more than 90 days or in foreclosure were characterized as delinquent. Cash principal and interest that was advanced from servicers after a loan becomes greater than 90 days past due was recorded as a liability due to the servicer. When a delinquent loan previously placed on nonaccrual status had cured, meaning all delinquent principal and interest had been remitted by the borrower, the loan was placed back on accrual status. Commercial Loans We recognize interest income from commercial loans when earned and deemed collectible, or until a loan becomes past due based on the terms of the loan agreement. Any related origination fees, net of origination cost are amortized into interest income using the effective interest method over the life of the loan. Interest received after a loan becomes past due or impaired is used to reduce the outstanding loan principal balance. When a delinquent loan previously placed on nonaccrual status has cured, meaning all delinquent principal and interest have been remitted by the borrower, the loan is placed back on accrual status. Alternately, loans that have been individually impaired may be placed back on accrual status if restructured and after the loan is considered re-performing. A restructured loan is considered re-performing when the loan has been current for at least 12 months .
Cash and Cash Equivalents	Cash and Cash Equivalents We consider all highly liquid investments that have original or remaining maturity dates of three months or less when purchased to be cash equivalents. At December 31, 2017 , we had cash and cash equivalents in excess of the FDIC deposit insurance limit of $ 250,000 per institution. We mitigate our risk of loss by actively monitoring our counterparties.
Due from Counterparties/Collateral Held Payable	Due from Counterparties / Collateral Held Payable Due from counterparties represents cash posted with our counterparties as collateral for our derivatives and repurchase agreements. Collateral held payable represents cash posted with us by counterparties as collateral under our derivatives and repurchase agreements. To the extent we receive collateral other than cash from our counterparties, such assets are not included in our consolidated balance sheets. Notwithstanding the foregoing, if we either sell such assets or pledge the assets as collateral pursuant to a repurchase agreement, the cash received and the corresponding liability is reflected on the consolidated balance sheets.
Investment Related Receivable / Investment Related Payable	Investment Related Receivable / Investment Related Payable Investment related receivable consists of receivables for mortgage-backed and credit risk transfer securities that we have sold but have not settled with the buyer and accrued interest and principal paydowns on mortgage-backed and credit risk transfer securities. Investment related payable consists of liabilities for mortgage-backed and credit risk transfer securities that we have purchased but have not settled with the seller.
Investments in Unconsolidated Ventures	Investments in Unconsolidated Ventures Our non-controlling investments in unconsolidated ventures are included in other assets in our consolidated balance sheets and are accounted for under the equity method. Capital contributions, distributions, profits and losses of the entities are allocated in accordance with the terms of the entities’ operating agreements. Such allocations may differ from the stated percentage interests, if any, as a result of preferred returns and allocation formulas as described in the entities' operating agreements.
Repurchase Agreements	Repurchase Agreements We finance our purchases of mortgage-backed and credit risk transfer securities primarily through the use of repurchase agreements. Repurchase agreements are treated as collateralized financing transactions and are carried at their contractual amounts, including accrued interest, as specified in the respective agreements. We record the mortgage-backed and credit risk transfer securities and the related repurchase agreement financing on a gross basis in our consolidated balance sheets, and the corresponding interest income and interest expense on a gross basis in our consolidated statements of operations.
Secured Loans	Secured Loans Our wholly-owned subsidiary, IAS Services LLC, is a member of the Federal Home Loan Bank of Indianapolis ("FHLBI"). As a member of the FHLBI, IAS Services LLC has borrowed funds from the FHLBI in the form of secured advances. FHLBI advances are treated as secured financing transactions and are carried at their contractual amounts.
Dividends and Distributions Payable	Dividends and Distributions Payable Dividends and distributions payable represent dividends declared at the balance sheet date which are payable to common stockholders, preferred stockholders, and an Invesco wholly-owned subsidiary, the non-controlling interest common unit holder of the Operating Partnership.
Earnings (Loss) per Share	Earnings (Loss) per Share We calculate basic earnings (loss) per share by dividing net income (loss) attributable to common stockholders for the period by the weighted-average number of shares of our common stock outstanding for that period. Diluted earnings per share takes into account the effect of dilutive instruments, such as units of limited partnership interest in the Operating Partnership ("OP Units"), exchangeable debt, and unvested restricted stock and uses the average share price for the period in determining the number of incremental shares that are to be added to the weighted-average number of shares outstanding.
Share-Based Compensation	Share-Based Compensation We adopted an equity incentive plan under which our independent directors, as part of their compensation for serving as directors, are eligible to receive quarterly stock awards. In addition, we may compensate the officers and employees of our Manager and its affiliates under this equity incentive plan under the terms of our management agreement. Share-based compensation arrangements include share options, restricted and non-restricted share awards, performance-based awards and share appreciation rights. Compensation related to stock awards to our independent directors is recognized in the consolidated financial statements based on the fair value of the equity or liability instruments issued on the date of grant. Compensation related to stock awards to employees of our Manager and its affiliates is recorded at the estimated fair value of the award over the vesting period of the award. We make an upward or downward adjustment to compensation expense for the difference in the fair value at the date of grant and the date the award is earned.
Underwriting Commissions and Offering Costs	Underwriting Commissions and Offering Costs Underwriting commissions and direct costs incurred in connection with our common and preferred stock offerings are reflected as a reduction of additional paid-in-capital and preferred stock, respectively.
Comprehensive Income	Comprehensive Income Our comprehensive income consists of net income, as presented in the consolidated statements of operations, adjusted for unrealized gains and losses on MBS purchased prior to September 1, 2016 and the debt host contract associated with GSE CRTs purchased prior to August 24, 2015; reclassification of amortization of net deferred gains and losses on de-designated interest rate swaps to repurchase agreements interest expense and currency translation adjustments on an investment in an unconsolidated venture. Unrealized gains and losses on our MBS purchased prior to September 1, 2016 and the debt host contract associated with GSE CRTs purchased prior to August 24, 2015 are reclassified into net income upon their sale.
Accounting for Derivative Financial Instruments	Accounting for Derivative Financial Instruments We record all derivatives on our consolidated balance sheets at fair value. At the inception of a derivative contract, we determine whether the instrument will be part of a qualifying hedge accounting relationship or whether we will account for the contract as a trading instrument. We have elected not to apply hedge accounting to all new derivative contracts entered into after January 1, 2014. Changes in the fair value of our derivatives are recorded in gain (loss) on derivative instruments, net in our consolidated statements of operations. Net interest paid or received under our interest rate swaps is also recognized in gain (loss) on derivative instruments, net in our consolidated statements of operations. Prior to 2014, we applied hedge accounting to our interest rate swap agreements. Effective December 31, 2013, we voluntarily discontinued hedge accounting for our interest rate swap agreements by de-designating the interest rate swaps as cash flow hedges. As long as we expect the forecasted transactions that were being hedged (i.e., rollovers of our repurchase agreement borrowings) to still occur, the balance recorded in accumulated other comprehensive income (loss) (“AOCI”) from the interest rate swap activity up through December 31, 2013 will remain in AOCI and be recognized in our consolidated statements of operations as interest expense over the remaining term of the interest rate swaps. We may enter into derivative contracts, such as credit default swaps, that are intended to economically hedge certain of its risks, even though hedge accounting does not apply or we elect not to apply hedge accounting under U.S. GAAP. We are a party to hybrid financial instruments that contain embedded derivative instruments. For securities that we did not elect the fair value option, we assess at inception, whether the economic characteristics of the embedded derivative instruments are clearly and closely related to the economic characteristics of the remaining component of the financial instrument (i.e., the debt host contract), whether the financial instrument is remeasured to fair value through earnings and whether a separate instrument with the same terms as the embedded instrument would meet the definition of a derivative instrument. When it is determined that (1) the embedded instrument possesses economic characteristics that are not clearly and closely related to the economic characteristics of the debt host contract, (2) the financial instrument is not remeasured to fair value through earnings and (3) a separate instrument with the same terms would qualify as a derivative instrument, the embedded instrument qualifies as an embedded derivative that is separated from the debt host contract. The embedded derivative is recorded at fair value, and changes in fair value are recorded in realized and unrealized credit derivative income (loss), net in our consolidated statements of operations. We evaluate the terms and conditions of our holdings of swaptions, futures contracts, currency forward contracts and to-be-announced ("TBA") securities to determine if an instrument has the characteristics of an investment or should be considered a derivative under U.S. GAAP. Accordingly swaptions, futures contracts, currency forward contracts and TBAs having the characteristics of derivatives are accounted for at fair value with such changes recognized in gain (loss) on derivative instruments, net in the consolidated statements of operations. The fair value of these swaptions, futures contracts, currency forward contracts and TBAs is included in derivative assets or derivative liabilities on the consolidated balance sheets.
Income Taxes	Income Taxes We elected to be taxed as a REIT commencing with our taxable year ended December 31, 2009. Accordingly, we will generally not be subject to U.S. federal and applicable state and local corporate income tax to the extent that we make qualifying distributions to our stockholders, and provided we satisfy on a continuing basis, through actual investment and operating results, the REIT requirements including certain asset, income, distribution and stock ownership tests. If we fail to qualify as a REIT and do not qualify for certain statutory relief provisions, we will be subject to U.S. federal, state and local income taxes and may be precluded from qualifying as a REIT for the four taxable years following the year in which we lost our REIT qualification. Accordingly, our failure to qualify as a REIT could have a material adverse impact on our results of operations and amounts available for distribution to stockholders. Our dividends paid deduction for qualifying dividends to our stockholders is computed using our REIT taxable income as opposed to net income reported on the consolidated financial statements. REIT taxable income will generally differ from net income because the determination of REIT taxable income is based on tax regulations and not financial accounting principles. We have elected to treat one of our subsidiaries as a taxable REIT subsidiary (“TRS”). In general, a TRS may hold assets and engage in activities that we cannot hold or engage in directly and generally may engage in any real estate or non-real estate-related business. A TRS is subject to U.S. federal, state and local corporate income taxes. Our TRS did not generate material taxable income for the years ended December 31, 2017 , 2016 and 2015. We do not have any accruals for uncertain tax positions. We would recognize interest and penalties related to uncertain tax positions, if any, as income tax expense, which would be included in general and administrative expenses.
Reclassifications	Reclassifications Certain prior period reported amounts have been reclassified to be consistent with the current presentation. Such reclassifications had no impact on total assets, net income or equity attributable to common stockholders.
Accounting Pronouncements Recently Adopted and Pending Accounting Pronouncements	Accounting Pronouncements Recently Adopted and Pending Accounting Pronouncements In January 2016, the FASB issued guidance to improve certain aspects of classification and measurement of financial instruments, including significant revisions in accounting related to the classification and measurement of investments in equity securities and presentation of certain fair value changes for financial liabilities when the fair value option is elected. The guidance also amends certain disclosure requirements associated with the fair value of financial instruments. We are required to adopt the new guidance in the first quarter of 2018. Early adoption is permitted. We have determined that this new accounting standard will not have an impact on our financial condition or results of operations but will simplify financial statement disclosures. In June 2016, the FASB issued an amendment to the guidance on reporting credit losses for assets measured at amortized cost and available-for-sale securities. We are required to adopt the new guidance in the first quarter of 2020. Early adoption is permitted. We are currently evaluating the potential impacts of the new guidance on our consolidated financial statements, as well as available transition methods. In August 2016, the FASB issued new guidance that is intended to reduce diversity in practice in how certain transactions are classified in the statement of cash flows. Additionally, in November 2016, the FASB issued new guidance on classification and presentation of changes in restricted cash on the statement of cash flows. We are required to adopt the new accounting standards in the first quarter of 2018 using a retrospective transition method for each period presented. Early adoption is permitted. We have determined that this new guidance will impact the presentation of certain cash payments and receipts among the operating, investing and financing sections of our consolidated statements of cash flows primarily related to distributions from investments in unconsolidated ventures and basis recovered on certain investment securities. In August 2017, the FASB issued guidance to improve accounting for hedging activities. The purpose of this updated guidance is to better align a company’s financial reporting for hedging activities with the economic objectives of those activities. We are required to adopt the new guidance in the first quarter of 2019. We have determined that this new guidance is not expected to have an impact on our consolidated financial statements because we have elected not to apply hedge accounting to all new derivative contracts entered into after January 1, 2014.

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2017
Variable Interest Entity Disclosure [Abstract]
Maximum Risk of Loss	Our maximum risk of loss in VIEs in which we are not the primary beneficiary at December 31, 2017 is presented in the table below. $ in thousands Carrying Amount Company's Maximum Risk of Loss CMBS 3,216,417 3,216,417 Non-Agency RMBS 1,257,608 1,257,608 Investments in unconsolidated ventures 25,972 25,972 Total 4,499,997 4,499,997
Gain (Loss) on Deconsolidation of VIEs	The following table presents the components of the net loss on deconsolidation of VIEs. $ in thousands As of December 9, 2015 Gain (loss) related to derecognition of Residential Securitizations, net (13,260 ) Gain (loss) related to remeasurement of retained interest, net 3,068 Gain (loss) on sale of the securities, net (9,431 ) Total gain (loss) on deconsolidation of VIEs, net (19,623 )
Impact of Deconsolidation on Financial Statements	The following table summarizes the net income (loss) of the Residential Securitizations excluding the loss on deconsolidation: $ in thousands Year ended December 31, 2015 Interest income - Residential loans 110,908 Interest expense - Asset-backed securities 82,041 Net interest income 28,867 Reduction in provision for loan losses (213 ) Net interest income after reduction in provision for loan losses 29,080 Expenses - Consolidated securitization trusts 8,219 Net income 20,861

Mortgage-Backed and Credit Ri29

Mortgage-Backed and Credit Risk Transfer Securities (Tables)	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Summary of Investment Portfolio	The following tables summarize our MBS and GSE CRT portfolio by asset type at December 31, 2017 and 2016 . December 31, 2017 $ in thousands Principal/ Notional Unamortized Premium (Discount) Amortized Cost Unrealized Gain/ (Loss), net Fair Value Net Weighted Average Coupon (1) Period- end Weighted Average Yield (2) Quarterly Weighted Average Yield (3) Agency RMBS: 15 year fixed-rate 2,917,307 119,120 3,036,427 (61,645 ) 2,974,782 3.08 % 2.17 % 1.98 % 30 year fixed-rate 7,354,211 295,977 7,650,188 (9,648 ) 7,640,540 3.72 % 3.09 % 2.90 % ARM* 238,486 1,609 240,095 1,105 241,200 2.67 % 2.60 % 2.36 % Hybrid ARM 1,696,148 26,066 1,722,214 (2,829 ) 1,719,385 2.70 % 2.54 % 2.25 % Total Agency pass-through (4) 12,206,152 442,772 12,648,924 (73,017 ) 12,575,907 3.40 % 2.79 % 2.58 % Agency-CMO (5) 1,226,539 (942,290 ) 284,249 (10,306 ) 273,943 2.05 % 2.91 % 2.74 % CMBS (6)(7) 3,879,775 (704,097 ) 3,175,678 40,739 3,216,417 3.85 % 4.92 % 4.77 % Non-Agency RMBS (8)(9)(10) 2,785,704 (1,661,683 ) 1,124,021 133,587 1,257,608 2.08 % 7.19 % 7.18 % GSE CRT (11)(12) 757,183 24,306 781,489 85,390 866,879 3.41 % 2.45 % 2.79 % Total 20,855,353 (2,840,992 ) 18,014,361 176,393 18,190,754 3.23 % 3.42 % 3.27 % *Adjustable-rate mortgage ("ARM") (1) Net weighted average coupon as of December 31, 2017 is based on principal/notional balance and is presented net of servicing and other fees. (2) Period-end weighted average yield is based on amortized cost as of December 31, 2017 and incorporates future prepayment and loss assumptions. (3) Quarterly weighted average yield for the period was calculated by dividing interest income, including amortization of premiums and discounts, by the average balance of the amortized cost of our investments. All yields are annualized. (4) We have elected the fair value option for Agency RMBS purchased on or after September 1, 2016 which represent 42.3% of principal/notional balance, 42.0% of amortized cost and 42.2% of fair value. (5) Agency collateralized mortgage obligation ("Agency-CMO") includes interest-only securities ("Agency IO"), which represent 81.8% of principal/notional balance, 20.9% of amortized cost and 18.7% of fair value. (6) CMBS includes interest-only securities which represent 15.8% of principal/ notional balance, 0.5% of amortized cost and 0.6% of fair value. (7) We have elected the fair value option for CMBS purchased on or after September 1, 2016 which represent 25.4% of principal/notional balance, 26.7% of amortized cost and 26.1% of fair value. (8) Non-Agency RMBS held by us is 52.2% variable rate, 37.8% fixed rate and 10.0% floating rate based on fair value. (9) Of the total discount in non-Agency RMBS, $195.3 million is non-accretable based on estimated future cash flows of the securities. (10) Non-Agency RMBS includes interest-only securities, which represent 51.5% of the principal/notional balance, 2.0% of amortized cost and 1.8% of fair value. (11) We have elected the fair value option for GSE CRTs purchased on or after August 24, 2015, which represent 26.7% of the balance based on fair value. As a result, GSE CRTs accounted for under the fair value option are not bifurcated between the debt host contract and the embedded derivative. (12) GSE CRT weighted average coupon and weighted average yield excludes coupon interest associated with embedded derivatives not accounted for under the fair value option that is recorded as realized and unrealized credit derivative income (loss), net. December 31, 2016 $ in thousands Principal/ Notional Balance Unamortized Premium (Discount) Amortized Cost Unrealized Gain/(Loss), net Fair Value Net Weighted Average Coupon (1) Period- end Weighted Average Yield (2) Quarterly Weighted Average Yield (3) Agency RMBS: 15 year fixed-rate 3,460,625 151,526 3,612,151 (54,223 ) 3,557,928 3.11 % 2.19 % 1.99 % 30 year fixed-rate 2,780,806 185,521 2,966,327 15,390 2,981,717 4.37 % 2.61 % 2.57 % ARM* 301,900 2,520 304,420 3,453 307,873 2.69 % 2.59 % 2.16 % Hybrid ARM 2,423,152 42,360 2,465,512 8,789 2,474,301 2.70 % 2.52 % 2.02 % Total Agency pass-through (4) 8,966,483 381,927 9,348,410 (26,591 ) 9,321,819 3.37 % 2.42 % 2.20 % Agency-CMO (5) 1,712,120 (1,368,916 ) 343,204 837 344,041 2.16 % 3.08 % 2.07 % CMBS (6)(7) 3,050,747 (559,857 ) 2,490,890 60,830 2,551,720 3.80 % 4.21 % 4.17 % Non-Agency RMBS (8)(9)(10) 3,838,314 (1,934,269 ) 1,904,045 91,506 1,995,551 2.21 % 5.22 % 5.22 % GSE CRT (11)(12) 707,899 24,320 732,219 35,981 768,200 2.38 % 1.51 % 1.24 % Total 18,275,563 (3,456,795 ) 14,818,768 162,563 14,981,331 3.05 % 3.05 % 2.87 % (1) Net weighted average coupon as of December 31, 2016 is based on principal/notional balance and is presented net of servicing and other fees. (2) Period-end weighted average yield is based on amortized cost as of December 31, 2016 and incorporates future prepayment and loss assumptions. (3) Quarterly weighted average yield for the period was calculated by dividing interest income, including amortization of premiums and discounts, by the average balance of the amortized cost of our investments. All yields are annualized. (4) We have elected the fair value option for Agency RMBS purchased on or after September 1, 2016 which represent 4.3% of principal/notional balance, 4.3% of amortized cost and 4.2% of fair value. (5) Agency collateralized mortgage obligation ("Agency CMO") includes interest-only securities ("Agency IO"), which represent 85.5% of principal/ notional balance, 26.8% of amortized cost and 27.1% of fair value. (6) CMBS includes interest-only securities which represent 20.3% of principal/notional balance, 0.8% of amortized cost and 0.9% of fair value. (7) We have elected the fair value option for CMBS purchased on or after September 1, 2016 which represent 0.4% of principal/notional balance, 0.6% of amortized cost and 0.5% of fair value. (8) Non-Agency RMBS held by us is 45.5% variable rate, 47.2% fixed rate, and 7.3% floating rate based on fair value. (9) Of the total discount in non-Agency RMBS, $252.5 million is non-accretable based on estimated future cash flows of the securities. (10) Non-Agency RMBS includes interest-only securities, which represent 43.5% of principal/notional balance, 1.5% of amortized cost and 1.3% of fair value. (11) We have elected the fair value option for GSE CRTs purchased on or after August 24, 2015, which represent 19.2% of the balance based on fair value. As a result, GSE CRTs accounted for under the fair value option are not bifurcated between the debt host contract and the embedded derivative. (12) GSE CRT weighted average coupon and weighted average yield excludes coupon interest associated with embedded derivatives not accounted for under the fair value option that is recorded as realized and unrealized credit derivative income (loss), net. The components of the carrying value of our MBS and GSE CRT portfolio at December 31, 2017 and 2016 are presented below. $ in thousands December 31, 2017 December 31, 2016 Principal/ notional balance 20,855,353 18,275,563 Unamortized premium 521,626 476,314 Unamortized discount (3,362,618 ) (3,933,109 ) Gross unrealized gains 341,656 302,099 Gross unrealized losses (165,263 ) (139,536 ) Fair value 18,190,754 14,981,331
Components of Non-Agency RMBS Portfolio by Asset Type	The following table summarizes our non-Agency RMBS portfolio by asset type as of December 31, 2017 and 2016 . $ in thousands December 31, 2017 % of Non-Agency December 31, 2016 % of Non-Agency Prime 649,671 51.6 % 889,658 44.6 % Alt-A 393,899 31.3 % 447,213 22.4 % Re-REMIC 173,110 13.7 % 364,301 18.2 % Subprime/reperforming 40,928 3.4 % 294,379 14.8 % Total Non-Agency 1,257,608 100.0 % 1,995,551 100.0 %
Components of Senior Re-REMIC at Fair Value	The following table summarizes the credit enhancement provided to our re-securitization of real estate mortgage investment conduit ("Re-REMIC") holdings as of December 31, 2017 and 2016 . Percentage of Re-REMIC Holdings at Fair Value Re-REMIC Subordination (1) December 31, 2017 December 31, 2016 0% - 10% 34.5 % 17.6 % 10% - 20% 3.7 % 7.4 % 20% - 30% 12.3 % 13.5 % 30% - 40% 18.4 % 15.7 % 40% - 50% 9.6 % 27.0 % 50% - 60% 19.7 % 16.1 % 60% - 70% 1.8 % 2.7 % Total 100.0 % 100.0 % (1) Subordination refers to the credit enhancement provided to the Re-REMIC tranche held by us by any junior Re-REMIC tranche or tranches in a resecuritization. This figure reflects the percentage of the balance of the underlying securities represented by any junior tranche or tranches at the time of resecuritization. Generally, principal losses on the underlying securities in excess of the subordination amount would result in principal losses on the Re-REMIC tranche held by us. Approximately 57.5% of our Re-REMIC holdings are not senior tranches.
Fair Value of MBS and GSE CRTs According to Weighted Average Life Classification	The following table summarizes our MBS and GSE CRT portfolio according to estimated weighted average life classifications as of December 31, 2017 and 2016 . $ in thousands December 31, 2017 December 31, 2016 Less than one year 135,559 121,076 Greater than one year and less than five years 7,934,836 6,719,923 Greater than or equal to five years 10,120,359 8,140,332 Total 18,190,754 14,981,331
Unrealized Losses and Estimated Fair Value of MBS and GSE CRTs by Length of Time	The following tables present the estimated fair value and gross unrealized losses of our MBS and GSE CRTs by length of time that such securities have been in a continuous unrealized loss position at December 31, 2017 and 2016 . December 31, 2017 Less than 12 Months 12 Months or More Total $ in thousands Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Agency RMBS: 15 year fixed-rate 111,020 (321 ) 26 2,406,021 (67,285 ) 133 2,517,041 (67,606 ) 159 30 year fixed-rate 3,677,576 (20,730 ) 107 963,547 (27,158 ) 56 4,641,123 (47,888 ) 163 ARM 101,173 (902 ) 12 — — — 101,173 (902 ) 12 Hybrid ARM 614,321 (4,189 ) 73 517,642 (8,091 ) 47 1,131,963 (12,280 ) 120 Total Agency pass through (1) 4,504,090 (26,142 ) 218 3,887,210 (102,534 ) 236 8,391,300 (128,676 ) 454 Agency-CMO (2) 75,299 (10,433 ) 44 81,988 (2,309 ) 5 157,287 (12,742 ) 49 CMBS (3) 892,553 (17,612 ) 81 135,139 (3,792 ) 12 1,027,692 (21,404 ) 93 Non-Agency RMBS 84,439 (709 ) 15 96,263 (1,732 ) 11 180,702 (2,441 ) 26 Total 5,556,381 (54,896 ) 358 4,200,600 (110,367 ) 264 9,756,981 (165,263 ) 622 (1) Amounts disclosed include Agency RMBS with a fair value of $3.4 billion for which the fair value option has been elected. Such securities have unrealized losses of $22.8 million . (2) Fair value includes unrealized losses on Agency IO of $10.1 million and unrealized losses on CMO of $2.7 million . (3) Amounts disclosed include CMBS with a fair value of $596.0 million for which the fair value option has been elected. Such securities have unrealized losses of $8.9 million . December 31, 2016 Less than 12 Months 12 Months or More Total $ in thousands Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Fair Value Unrealized Losses Number of Securities Agency RMBS: 15 year fixed-rate 2,781,777 (66,506 ) 127 65,964 (1,556 ) 17 2,847,741 (68,062 ) 144 30 year fixed-rate 747,719 (15,409 ) 45 547,763 (18,004 ) 27 1,295,482 (33,413 ) 72 ARM 120,540 (326 ) 9 1,091 (7 ) 1 121,631 (333 ) 10 Hybrid ARM 1,356,687 (9,922 ) 99 252 (4 ) 2 1,356,939 (9,926 ) 101 Total Agency pass through (1) 5,006,723 (92,163 ) 280 615,070 (19,571 ) 47 5,621,793 (111,734 ) 327 Agency-CMO (2) 163,114 (3,812 ) 28 22,792 (952 ) 3 185,906 (4,764 ) 31 CMBS (3) 401,016 (6,733 ) 36 47,219 (804 ) 6 448,235 (7,537 ) 42 Non-Agency RMBS 287,647 (7,861 ) 42 497,863 (6,671 ) 36 785,510 (14,532 ) 78 GSE CRT (4) — — — 35,935 (969 ) 3 35,935 (969 ) 3 Total 5,858,500 (110,569 ) 386 1,218,879 (28,967 ) 95 7,077,379 (139,536 ) 481 (1) Amounts disclosed include Agency RMBS with a fair value of $149.7 million for which the fair value option has been elected. Such securities have unrealized losses of $4.0 million . (2) Fair value includes unrealized losses on Agency IO of $3.0 million and unrealized losses on CMO of $1.7 million . (3) Amounts disclosed includes CMBS with a fair value of $13.9 million for which the fair value option has been elected. Such securities have unrealized losses of $613,000 . (4) Fair value includes unrealized losses on both the debt host contract and the embedded derivative.
Changes in other than temporary impairment included in earnings	The following table represents OTTI included in earnings for the years ended December 31, 2017 and 2016 . We did not record any OTTI for the year ended December 31, 2015 . Years Ended December 31, $ in thousands 2017 2016 RMBS interest-only securities 11,208 8,334 Non-Agency RMBS (1) 754 575 Total 11,962 8,909 (1) Amounts disclosed relate to credit losses on debt securities for which a portion of an other-than-temporary impairment was recognized in other comprehensive income.
Gain (Loss) on Investments	The following table summarizes the components of our total gain (loss) on investments, net for the years ended December 31, 2017 , 2016 and 2015 . As of December 31, 2017 , $6.5 billion ( December 31, 2016 : $427.5 million ) or 35.6% ( December 31, 2016 : 2.9% ) of our MBS and GSE CRT are accounted for under the fair value option. Under the fair value option, changes in fair value are recognized as a component of gain (loss) on investments, net in our consolidated statements of operations. Years Ended December 31, $ in thousands 2017 2016 2015 Gross realized gains on sale of investments 2,208 14,196 13,346 Gross realized losses on sale of investments (3,873 ) (21,635 ) (11,114 ) Other-than-temporary impairment losses (11,962 ) (8,909 ) — Net unrealized gains and losses on MBS accounted for under the fair value option (21,368 ) (5,791 ) (558 ) Net unrealized gains and losses on GSE CRT accounted for under the fair value option 15,269 4,598 (56 ) Net unrealized gains and losses on trading securities 22 (1 ) — Total gain (loss) on investments, net (1) (19,704 ) (17,542 ) 1,618 (1) Balance as of December 31, 2015 excludes the loss on deconsolidation of VIEs of $19.6 million . Refer to Note 3 - "Variable Interest Entities" for further discussion.
Components of MBS and GSE CRT Interest Income	The following tables present components of interest income recognized on our MBS and GSE CRT portfolio for the years ended December 31, 2017 , 2016 and 2015 . GSE CRT interest income excludes coupon interest associated with embedded derivatives not accounted for under the fair value option that is recorded as realized and unrealized credit derivative income (loss), net. For the Year ended December 31, 2017 $ in thousands Coupon Interest Net (Premium Amortization)/ Discount Accretion Interest Income Agency 392,248 (107,702 ) 284,546 CMBS 131,005 (4,268 ) 126,737 Non-Agency 70,849 18,769 89,618 GSE CRT 22,164 (1,949 ) 20,215 Other 431 — 431 Total 616,697 (95,150 ) 521,547 For the Year ended December 31, 2016 $ in thousands Coupon Interest Net (Premium Amortization)/Discount Accretion Interest Income Agency 346,783 (116,991 ) 229,792 CMBS 122,636 (11,536 ) 111,100 Non-Agency 94,206 13,529 107,735 GSE CRT 9,575 (3,192 ) 6,383 Other 1,492 (58 ) 1,434 Total 574,692 (118,248 ) 456,444 For the Year ended December 31, 2015 $ in thousands Coupon Interest Net (Premium Amortization)/Discount Accretion Interest Income Agency 372,610 (121,170 ) 251,440 CMBS 149,977 (11,322 ) 138,655 Non-Agency 110,885 18,287 129,172 GSE CRT 6,681 (3,088 ) 3,593 Other 1,028 5 1,033 Total 641,181 (117,288 ) 523,893

Commercial Loans Held-for-Inv30

Commercial Loans Held-for-Investment (Tables)	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Schedule of Commercial Loans Held for Investment	The following tables summarize commercial loans held-for-investment as of December 31, 2017 and 2016 that we purchased or originated. December 31, 2017 $ in thousands Number of loans Principal Balance Unamortized (fees)/ costs, net Carrying value Weighted Average Coupon Weighted Average Years to Maturity (1) Mezzanine loans 8 191,894 (86 ) 191,808 8.52 % 1.2 December 31, 2016 $ in thousands Number of loans Principal Balance Unamortized (fees)/ costs, net Carrying value Weighted Average Weighted Average Years to Maturity (1) Mezzanine loans 10 273,666 (311 ) 273,355 8.14 % 1.6 (1) Weighted average years to maturity is based on the contractual maturity date. Certain loans may contain either an option to prepay or an option to extend beyond their contractual maturity dates as specified in the respective loan agreements.

Other Assets (Tables)

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Schedule of Investments [Abstract]
Schedule of other assets	The following table summarizes our other assets as of December 31, 2017 and 2016 : $ in thousands December 31, 2017 December 31, 2016 FHLBI stock 74,250 74,250 Investments in unconsolidated ventures 25,972 33,301 Investment in exchange-traded fund 3,979 500 Prepaid expenses and other assets 1,379 1,246 Total 105,580 109,297

Borrowings (Tables)

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Borrowings	The following tables summarize certain characteristics of our borrowings at December 31, 2017 and 2016 . Refer to Note 8 - "Collateral Positions" for collateral pledged under our repurchase agreements and secured loans. $ in thousands December 31, 2017 Amount Outstanding Weighted Average Interest Rate Weighted Average Remaining Maturity (Days) Repurchase Agreements: Agency RMBS 11,111,755 1.58 % 25 CMBS 1,396,330 2.61 % 9 Non-Agency RMBS 915,225 2.77 % 31 GSE CRT 657,491 2.78 % 24 Total Repurchase Agreements 14,080,801 1.82 % 25 Secured Loans 1,650,000 1.52 % 2,317 Exchangeable Senior Notes (1) 143,410 5.00 % 74 Total Borrowings 15,874,211 1.82 % 263 $ in thousands December 31, 2016 Amount Weighted Weighted Repurchase Agreements: Agency RMBS 8,148,220 0.93 % 32 CMBS 944,718 1.86 % 16 Non-Agency RMBS 1,519,859 2.06 % 28 GSE CRT 547,872 2.25 % 16 Total Repurchase Agreements 11,160,669 1.23 % 30 Secured Loans 1,650,000 0.74 % 2,682 Exchangeable Senior Notes (1) 400,000 5.00 % 439 Total Borrowings 13,210,669 1.28 % 373 (1) The carrying value of exchangeable senior notes is $143.2 million and $397.0 million as of December 31, 2017 and 2016 , respectively. The carrying value is net of unamortized debt issuance costs of $179,000 and $3.0 million as of December 31, 2017 and 2016 , respectively.
Schedule of maturities of outstanding borrowings	The following table shows the aggregate amount of maturities of our outstanding borrowings: $ in thousands As of December 31, 2018 14,224,211 2019 — 2020 300,000 2021 100,000 2022 — Thereafter 1,250,000 Total 15,874,211
Schedule of Repurchase Agreements by Counterparties	The following tables summarize certain characteristics of our repurchase agreements and secured loans at December 31, 2017 and 2016 . December 31, 2017 $ in thousands Amount Outstanding Percent of Total Amount Outstanding MBS and GSE CRT Pledged as Collateral (1) Repurchase Agreement Counterparties: HSBC 1,745,684 11.2 % 1,839,411 ING Financial Markets 1,482,603 9.4 % 1,571,061 RBC 1,144,856 7.3 % 1,375,285 Industrial and Commercial Bank of China 1,038,844 6.6 % 1,102,543 E D & F Man Capital Markets 1,028,437 6.5 % 1,085,429 Mirae Asset Securities 958,756 6.1 % 1,018,664 MUFG Securities 865,201 5.5 % 936,071 Citigroup 724,094 4.6 % 841,977 Amherst Pierpont Securities 722,080 4.6 % 764,713 KGS-Alpha Capital Markets 461,098 2.9 % 491,313 JP Morgan 451,941 2.9 % 523,590 Societe Generale 386,737 2.5 % 495,093 BNP Paribas Securities 348,340 2.2 % 388,091 South Street Securities 332,623 2.1 % 354,689 Goldman Sachs 324,152 2.1 % 419,713 Mizuho Securities 310,835 2.0 % 330,555 Guggenheim Liquidity Services 306,081 1.9 % 322,452 Bank of Nova Scotia 289,705 1.8 % 301,715 Natixis Securities 275,764 1.8 % 302,291 All other repurchase agreement counterparties (2) 882,970 5.5 % 1,058,759 Total Repurchase Agreement Counterparties 14,080,801 89.5 % 15,523,415 Secured Loans Counterparty: FHLBI 1,650,000 10.5 % 1,927,496 Total 15,730,801 100.0 % 17,450,911 (1) Amounted pledged as collateral is measured at fair value as described in Note 2 - "Summary of Significant Accounting Policies." (2) Represents amounts outstanding with seven counterparties. December 31, 2016 $ in thousands Amount Outstanding Percent of Total Amount Outstanding MBS and GSE CRT Pledged as Collateral (1) Repurchase Agreement Counterparties: HSBC 1,401,966 11.2 % 1,468,793 ING Financial Markets 1,142,200 8.9 % 1,216,492 RBC 1,098,631 8.6 % 1,293,336 Industrial and Commercial Bank of China 707,616 5.5 % 748,503 MUFG Securities 703,382 5.5 % 740,404 Amherst Pierpont Securities 681,853 5.3 % 717,663 South Street Securities 675,660 5.3 % 713,330 Goldman Sachs 486,430 3.8 % 623,400 Bank of Nova Scotia 479,105 3.7 % 500,578 JP Morgan 477,947 3.7 % 554,494 KGS-Alpha Capital Markets 441,541 3.4 % 475,858 Citigroup 427,185 3.3 % 534,875 E D & F Man Capital Markets 405,615 3.2 % 430,896 Guggenheim Liquidity Services 356,149 2.8 % 377,030 Natixis Securities 336,202 2.6 % 362,432 Societe Generale 325,393 2.5 % 427,200 BNP Paribas Securities 307,641 2.4 % 346,484 All other repurchase agreement counterparties (2) 706,153 5.4 % 912,536 Total Repurchase Agreement Counterparties: 11,160,669 87.1 % 12,444,304 Secured Loans Counterparty: FHLBI 1,650,000 12.9 % 1,931,582 Total 12,810,669 100.0 % 14,375,886 (1) Amounted pledged as collateral is measured at fair value as described in Note 2 - "Summary of Significant Accounting Policies." (2) Represents amount outstanding with six counterparties.
Schedule of Retirements of Exchangeable Senior Notes	The following table summarizes retirements of the Notes during the year ended December 31, 2017 . $ in thousands Year Ended December 31, 2017 Reacquisition price 262,069 Par value of Notes retired (256,590 ) Write off of unamortized debt issuance cost associated with Notes retired 1,335 Net loss on extinguishment of debt 6,814

Collateral Positions (Tables)

Collateral Positions (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Fair Value of Collateral Hold and Pledged	The following table summarizes the fair value of collateral that we have pledged under our repurchase agreements, secured loans, interest rate swaps and currency forward contracts as of December 31, 2017 and 2016 . Refer to Note 2 - "Summary of Significant Accounting Policies - Fair Value Measurements" for a description of how we determine fair value. RMBS, CMBS and GSE CRT collateral pledged is included in mortgage-backed and credit risk transfer securities on our consolidated balance sheets. Cash collateral pledged on bilateral swaps and currency forwards is classified as due from counterparties on our consolidated balance sheets. Cash collateral held on bilateral swaps that is not restricted for use is included in cash and cash equivalents on our consolidated balance sheets and the liability to return the collateral is included in collateral held payable. Non-cash collateral held is only recognized if the counterparty defaults or if we sell the pledged collateral. As of December 31, 2017 and 2016 , we did not recognize any non-cash collateral held. $ in thousands As of Collateral Pledged December 31, 2017 December 31, 2016 Repurchase Agreements: Agency RMBS 11,788,765 8,654,233 CMBS 1,737,831 1,168,309 Non-Agency RMBS 1,143,373 1,887,550 GSE CRT 853,446 734,212 Total repurchase agreement collateral pledged 15,523,415 12,444,304 Secured Loans: Agency RMBS 623,181 585,504 CMBS 1,304,315 1,346,078 Total secured loans collateral pledged 1,927,496 1,931,582 Interest Rate Swaps and Currency Forward Contracts: Agency RMBS 23,705 46,312 Cash (1) 620 86,450 Total interest rate swaps and currency forward contracts collateral pledged 24,325 132,762 Total: Mortgage-backed and GSE CRT securities 17,474,616 14,422,198 Cash 620 86,450 Total collateral pledged 17,475,236 14,508,648 Collateral Held December 31, 2017 December 31, 2016 Interest Rate Swaps: Cash 7,327 1,700 Non-cash collateral — 536 Total collateral held 7,327 2,236 (1) Cash collateral pledged on our currency forward contracts was $620,000 as of December 31, 2017 . We did no t pledge any collateral on our currency forward contracts as of December 31, 2016 .

Derivatives and Hedging Activ34

Derivatives and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Outstanding Interest Rate Swaptions and Derivative Instrument Information	The following table summarizes changes in the notional amount of our derivative instruments during 2017 : $ in thousands Notional Amount as of January 1, 2017 Additions Settlement, Notional Amount as Interest Rate Swaps 6,500,000 2,620,000 — 9,120,000 Currency Forward Contracts 62,308 284,328 (269,777 ) 76,859 Credit Derivatives 569,966 — (16,473 ) 553,493 Total 7,132,274 2,904,328 (286,250 ) 9,750,352
Interest Rate Derivatives Outstanding	As of December 31, 2017 , we had the following interest rate derivatives outstanding: $ in thousands Counterparty Notional Maturity Date Fixed Interest Rate in Contract ING Capital Markets LLC 350,000 2/24/2018 0.95 % UBS AG 500,000 5/24/2018 1.10 % ING Capital Markets LLC 400,000 6/5/2018 0.87 % CME Central Clearing 300,000 2/5/2021 2.50 % CME Central Clearing 300,000 2/5/2021 2.69 % Wells Fargo Bank, N.A. 200,000 3/15/2021 3.14 % CME Central Clearing 500,000 5/24/2021 2.25 % Citibank, N.A. 200,000 5/25/2021 2.83 % CME Central Clearing 500,000 6/24/2021 2.44 % HSBC Bank USA, National Association 550,000 2/24/2022 2.45 % CME Central Clearing 1,000,000 6/9/2022 2.21 % CME Central Clearing 1,000,000 8/14/2022 1.87 % The Royal Bank of Scotland Plc 500,000 8/15/2023 1.98 % CME Central Clearing 600,000 8/24/2023 2.88 % HSBC Bank USA, National Association 500,000 12/15/2023 2.20 % CME Central Clearing 450,000 1/12/2024 2.10 % CME Central Clearing 450,000 1/25/2024 2.15 % CME Central Clearing 100,000 4/2/2025 2.04 % LCH Central Clearing 220,000 8/29/2027 2.12 % CME Central Clearing (1) 250,000 5/24/2028 2.78 % CME Central Clearing (1) 250,000 5/24/2028 2.39 % Total 9,120,000 2.13 % (1) Forward start date of 5/24/2018
Schedule of Credit Derivatives	As of December 31, 2017 and 2016 , terms of the GSE CRT embedded derivatives are: $ in thousands December 31, 2017 December 31, 2016 Fair value amount 45,400 17,095 Notional amount 553,493 569,966 Maximum potential amount of future undiscounted payments 553,493 569,966
Fair Value of Derivative Financial Instruments and Classification on Balance Sheet	The table below presents the fair value of our derivative financial instruments, as well as their classification on our consolidated balance sheets as of December 31, 2017 and 2016 . $ in thousands Derivative Assets Derivative Liabilities As of December 31, 2017 As of December 31, 2016 As of December 31, 2017 As of December 31, 2016 Balance Sheet Fair Value Fair Value Balance Sheet Fair Value Fair Value Interest Rate Swaps Asset 6,896 3,085 Interest Rate Swaps Liability 31,548 133,833 Currency Forward Contracts — 101 Currency Forward Contracts 1,217 395
Effect of Derivative Financial Instruments on Statement of Operations	The tables below present the effect of our credit derivatives on our consolidated statements of operations for the years ended December 31, 2017 , 2016 and 2015 . $ in thousands Year ended December 31, 2017 Derivative not designated as hedging instrument Realized gain (loss), net GSE CRT embedded derivative coupon interest Unrealized gain (loss), net Realized and unrealized credit derivative income (loss), net GSE CRT Embedded Derivatives — 23,343 28,305 51,648 $ in thousands Year ended December 31, 2016 Derivative not designated as hedging instrument Realized gain (loss), net GSE CRT embedded derivative coupon interest Unrealized gain (loss), net Realized and unrealized credit derivative income (loss), net GSE CRT Embedded Derivatives (6,017 ) 24,343 42,817 61,143 $ in thousands Year ended December 31, 2015 Derivative not designated as hedging instrument Realized gain (loss), net GSE CRT embedded derivative coupon interest Unrealized gain (loss), net Realized and unrealized credit derivative income (loss), net GSE CRT Embedded Derivatives (2,184 ) 24,822 (4,227 ) 18,411 Credit Default Swap Contract 1,044 723 (396 ) 1,371 Total (1,140 ) 25,545 (4,623 ) 19,782 The following tables summarize the effect of interest rate swaps, interest rate swaptions, TBAs, futures contracts and currency forward contracts reported in gain (loss) on derivative instruments, net on the consolidated statements of operations for the years ended December 31, 2017 , 2016 and 2015 . $ in thousands Year ended December 31, 2017 Derivative not designated as hedging instrument Realized gain (loss) on derivative instruments, net Contractual net interest expense Unrealized gain (loss), net Gain (loss) on derivative instruments, net Interest Rate Swaps 72,894 (77,076 ) 28,316 24,134 Currency Forward Contracts (5,056 ) — (923 ) (5,979 ) Total 67,838 (77,076 ) 27,393 18,155 $ in thousands Year ended December 31, 2016 Derivative not designated as hedging instrument Realized gain (loss) on derivative instruments, net Contractual net interest expense Unrealized gain (loss), net Gain (loss) on derivative instruments, net Interest Rate Swaps (69,090 ) (104,804 ) 100,503 (73,391 ) Interest Rate Swaptions (1,485 ) — 1,485 — Currency Forward Contracts 12,632 — (2,056 ) 10,576 Total (57,943 ) (104,804 ) 99,932 (62,815 ) $ in thousands Year ended December 31, 2015 Derivative Realized gain (loss) on derivative instruments, net Contractual net interest expense Unrealized gain (loss), net Gain (loss) on derivative instruments, net Interest Rate Swaps (31,881 ) (184,373 ) (554 ) (216,808 ) Interest Rate Swaptions (10,328 ) — 8,521 (1,807 ) TBAs (2,292 ) — 558 (1,734 ) Futures Contracts (943 ) — (90 ) (1,033 ) Currency Forward Contracts 1,172 — 1,162 2,334 Total (44,272 ) (184,373 ) 9,597 (219,048 )

Offsetting Assets and Liabili35

Offsetting Assets and Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Offsetting [Abstract]
Offsetting Assets	The following tables present information about the assets and liabilities that are subject to master netting arrangements (or similar agreements) and can potentially be offset on our consolidated balance sheets at December 31, 2017 and December 31, 2016 . As a result of rulebook changes governing central clearing activities effective January 3, 2017, the daily variation margin payment for a centrally cleared interest rate swaps is characterized as settlement of the derivative itself rather than collateral. Our derivative liability of $10.3 million at December 31, 2017 related to centrally cleared interest rate swaps is not included in the table below as a result of this change. Offsetting of Derivative Assets As of December 31, 2017 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Assets presented in the Consolidated Balance Sheets Financial Instruments Cash Collateral Received Net Amount Derivatives (1)(3) 6,896 — 6,896 — (6,896 ) — Offsetting of Derivative Liabilities, Repurchase Agreements and Secured Loans As of December 31, 2017 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Liabilities presented in the Consolidated Balance Sheets Financial Instruments (2) Cash Collateral Pledged Net Amount Derivatives (3) 22,445 — 22,445 (21,169 ) (620 ) 656 Repurchase Agreements (4) 14,080,801 — 14,080,801 (14,080,801 ) — — Secured Loans (5) 1,650,000 — 1,650,000 (1,650,000 ) — — Total 15,753,246 — 15,753,246 (15,751,970 ) (620 ) 656 Offsetting of Derivative Assets As of December 31, 2016 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Assets presented in the Consolidated Balance Sheets Financial Instruments Cash Collateral Received Net Amount Derivatives (1)(3) 3,186 — 3,186 (1,640 ) (1,546 ) — Offsetting of Derivative Liabilities and Repurchase Agreements As of December 31, 2016 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Liabilities presented in the Consolidated Balance Sheets Financial Instruments (2) Cash Collateral Pledged Net Amount Derivatives (3) 134,228 — 134,228 (45,738 ) (85,787 ) 2,703 Repurchase Agreements (4) 11,160,669 — 11,160,669 (11,160,669 ) — — Secured Loans (5) 1,650,000 — 1,650,000 (1,650,000 ) — — 12,944,897 — 12,944,897 (12,856,407 ) (85,787 ) 2,703 (1) Amounts represent derivatives in an asset position which could potentially be offset against derivatives in a liability position at December 31, 2017 and December 31, 2016 , subject to a netting arrangement. (2) Amounts represent collateral pledged that is available to be offset against liability balances associated with repurchase agreements, secured loans and derivatives. (3) The fair value of securities pledged against our derivatives was $23.7 million and $46.3 million at December 31, 2017 and December 31, 2016 , respectively. Cash collateral received on our derivatives was $7.3 million and $1.7 million at December 31, 2017 and December 31, 2016 , respectively. Cash collateral pledged by us on our derivatives was $620,000 and $86.5 million at December 31, 2017 and December 31, 2016 , respectively. As a result of rulebook changes governing central clearing activities effective January 3, 2017, cash collateral pledged on our centrally cleared interest rate swaps is settled against the fair value of these swaps and therefore excluded from the tables above at December 31, 2017 . (4) The fair value of securities pledged against our borrowing under repurchase agreements was $15.5 billion and $12.4 billion at December 31, 2017 and December 31, 2016 , respectively. (5) The fair value of securities pledged against IAS Services LLC's borrowing under secured loans was $1.9 billion and $1.9 billion at December 31, 2017 and December 31, 2016 , respectively.
Offsetting Liabilities	The following tables present information about the assets and liabilities that are subject to master netting arrangements (or similar agreements) and can potentially be offset on our consolidated balance sheets at December 31, 2017 and December 31, 2016 . As a result of rulebook changes governing central clearing activities effective January 3, 2017, the daily variation margin payment for a centrally cleared interest rate swaps is characterized as settlement of the derivative itself rather than collateral. Our derivative liability of $10.3 million at December 31, 2017 related to centrally cleared interest rate swaps is not included in the table below as a result of this change. Offsetting of Derivative Assets As of December 31, 2017 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Assets presented in the Consolidated Balance Sheets Financial Instruments Cash Collateral Received Net Amount Derivatives (1)(3) 6,896 — 6,896 — (6,896 ) — Offsetting of Derivative Liabilities, Repurchase Agreements and Secured Loans As of December 31, 2017 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Liabilities presented in the Consolidated Balance Sheets Financial Instruments (2) Cash Collateral Pledged Net Amount Derivatives (3) 22,445 — 22,445 (21,169 ) (620 ) 656 Repurchase Agreements (4) 14,080,801 — 14,080,801 (14,080,801 ) — — Secured Loans (5) 1,650,000 — 1,650,000 (1,650,000 ) — — Total 15,753,246 — 15,753,246 (15,751,970 ) (620 ) 656 Offsetting of Derivative Assets As of December 31, 2016 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Assets Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Assets presented in the Consolidated Balance Sheets Financial Instruments Cash Collateral Received Net Amount Derivatives (1)(3) 3,186 — 3,186 (1,640 ) (1,546 ) — Offsetting of Derivative Liabilities and Repurchase Agreements As of December 31, 2016 Gross Amounts Not Offset in the Consolidated Balance Sheets $ in thousands Description Gross Amounts of Recognized Liabilities Gross Amounts Offset in the Consolidated Balance Sheets Net Amounts of Liabilities presented in the Consolidated Balance Sheets Financial Instruments (2) Cash Collateral Pledged Net Amount Derivatives (3) 134,228 — 134,228 (45,738 ) (85,787 ) 2,703 Repurchase Agreements (4) 11,160,669 — 11,160,669 (11,160,669 ) — — Secured Loans (5) 1,650,000 — 1,650,000 (1,650,000 ) — — 12,944,897 — 12,944,897 (12,856,407 ) (85,787 ) 2,703 (1) Amounts represent derivatives in an asset position which could potentially be offset against derivatives in a liability position at December 31, 2017 and December 31, 2016 , subject to a netting arrangement. (2) Amounts represent collateral pledged that is available to be offset against liability balances associated with repurchase agreements, secured loans and derivatives. (3) The fair value of securities pledged against our derivatives was $23.7 million and $46.3 million at December 31, 2017 and December 31, 2016 , respectively. Cash collateral received on our derivatives was $7.3 million and $1.7 million at December 31, 2017 and December 31, 2016 , respectively. Cash collateral pledged by us on our derivatives was $620,000 and $86.5 million at December 31, 2017 and December 31, 2016 , respectively. As a result of rulebook changes governing central clearing activities effective January 3, 2017, cash collateral pledged on our centrally cleared interest rate swaps is settled against the fair value of these swaps and therefore excluded from the tables above at December 31, 2017 . (4) The fair value of securities pledged against our borrowing under repurchase agreements was $15.5 billion and $12.4 billion at December 31, 2017 and December 31, 2016 , respectively. (5) The fair value of securities pledged against IAS Services LLC's borrowing under secured loans was $1.9 billion and $1.9 billion at December 31, 2017 and December 31, 2016 , respectively.

Fair Value of Financial Instr36

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Values Measured on Recurring Basis	The following tables present our assets and liabilities measured at fair value on a recurring basis. December 31, 2017 Fair Value Measurements Using: $ in thousands Level 1 Level 2 Level 3 NAV as a practical expedient (3) Total at Fair Value Assets: Mortgage-backed and credit risk transfer securities (1) (2) — 18,145,354 45,400 — 18,190,754 Derivative assets — 6,896 — — 6,896 Other assets (4) 3,979 — — 25,972 29,951 Total assets 3,979 18,152,250 45,400 25,972 18,227,601 Liabilities: Derivative liabilities — 32,765 — — 32,765 Total liabilities — 32,765 — — 32,765 December 31, 2016 Fair Value Measurements Using: $ in thousands Level 1 Level 2 Level 3 NAV as a practical expedient (3) Total at Fair Value Assets: Mortgage-backed and credit risk transfer securities (1) (2) — 14,964,236 17,095 — 14,981,331 Derivative assets — 3,186 — 3,186 Other assets (4) 500 — — 33,301 33,801 Total assets 500 14,967,422 17,095 33,301 15,018,318 Liabilities: Derivative liabilities — 134,228 — — 134,228 Total liabilities — 134,228 — — 134,228 (1) For more detail about the fair value of our MBS and GSE CRTs, refer to Note 4 - "Mortgage-Backed and Credit Risk Transfer Securities." (2) Our GSE CRTs purchased prior to August 24, 2015 are accounted for as hybrid financial instruments with an embedded derivative. The hybrid instruments consist of debt host contracts classified as Level 2 and embedded derivatives classified as Level 3. As of December 31, 2017 , the net embedded derivative asset position of $45.4 million includes $46.5 million of embedded derivatives in an asset position and $1.1 million of embedded derivatives in a liability position. As of December 31, 2016 , the net embedded derivative asset position of $17.1 million includes $21.0 million of embedded derivatives in an asset position and $3.9 million of embedded derivatives in a liability position. (3) Investments in unconsolidated ventures are valued using the net asset value ("NAV") as a practical expedient and are not subject to redemption, although investors may sell or transfer their interest at the approval of the general partner of the underlying funds. As of December 31, 2017 and December 31, 2016 , the weighed average remaining term of investments in unconsolidated ventures is 1.9 years and 1.3 years, respectively. (4) Includes $4.0 million and $500,000 of investments in an exchange-traded fund as of December 31, 2017 and December 31, 2016 , respectively.
Net Derivative Asset (Liability) Level 3 Roll Forward	The following table shows a reconciliation of the beginning and ending fair value measurements of our GSE CRT embedded derivatives, which we have valued utilizing Level 3 inputs: Years Ended $ in thousands December 31, 2017 December 31, 2016 Beginning balance 17,095 (25,722 ) Sales and settlements — 6,017 Total net gains / (losses) included in net income: Realized gains/(losses), net — (6,017 ) Unrealized gains/(losses), net (1) 28,305 42,817 Ending balance 45,400 17,095 (1) Included in realized and unrealized credit derivative income (loss), net in the consolidated statements of operations are $28.3 million in net unrealized gains and $36.2 million in net unrealized gains attributable to assets still held as of December 31, 2017 and December 31, 2016 , respectively. During the year ended December 31, 2016 , we reversed $6.6 million in net unrealized gains on securities sold during the period.
Net Derivative Asset (Liability), Fair Value Inputs	The following tables summarize significant unobservable inputs used in the fair value measurement of our GSE CRT embedded derivatives: Fair Value at $ in thousands December 31, 2017 Valuation Technique Unobservable Input Range Weighted Average GSE CRT Embedded Derivatives 45,400 Market Comparables, Vendor Pricing Weighted average life 2.6 - 6.8 years 4.8 years Fair Value at $ in thousands December 31, 2016 Valuation Technique Unobservable Input Range Weighted Average GSE CRT Embedded Derivatives 17,095 Market Comparables, Vendor Pricing Weighted average life 2.5 - 7.7 years 5.3 years
Carrying Values And Estimated Fair Value of Financial Instruments	The following table presents the carrying value and estimated fair value of our financial instruments that are not carried at fair value on the consolidated balance sheets at December 31, 2017 and December 31, 2016 : December 31, 2017 December 31, 2016 $ in thousands Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value Financial Assets: Commercial loans, held-for-investment 191,808 191,930 273,355 275,319 Other assets 74,250 74,250 74,250 74,250 Total 266,058 266,180 347,605 349,569 Financial Liabilities: Repurchase agreements 14,080,801 14,080,460 11,160,669 11,161,034 Secured loans 1,650,000 1,650,000 1,650,000 1,650,000 Exchangeable senior notes 143,231 143,948 397,041 400,000 Total 15,874,032 15,874,408 13,207,710 13,211,034

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	The following table summarizes the costs incurred on our behalf by our Manager for the years ended December 31, 2017 , 2016 and 2015 . Years ended December 31, $ in thousands 2017 2016 2015 Incurred costs, prepaid or expensed 5,997 6,986 6,463 Incurred costs, charged against equity as a cost of raising capital 299 — 22 Incurred costs, capitalized to other assets — 50 — Total incurred costs, originally paid by our Manager 6,296 7,036 6,485

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Schedule of Nonvested Restricted Stock Shares Activity	The following table summarizes the activity related to restricted stock units awarded to employees of our Manager and its affiliates for the year ended December 31, 2017 . Year Ended December 31, 2017 Restricted Stock Units Weighted Average Grant Date Fair Value (1) Unvested at the beginning of the year 18,807 $ 14.37 Shares granted during the year 8,115 15.55 Shares vested during the year (7,095 ) 15.78 Unvested at the end of the year 19,827 $ 14.35 (1) The grant date fair value of restricted stock unit awards is based on the closing market price of our common stock at the grant date.
Schedule of Accumulated Other Comprehensive Income	The following tables present the components of total other comprehensive income (loss), net and accumulated other comprehensive income ("AOCI") at December 31, 2017 and December 31, 2016 , respectively. The tables exclude gains and losses on MBS and GSE CRTs that are accounted for under the fair value option. December 31, 2017 $ in thousands Equity method investments Available-for-sale securities Derivatives and hedging Total Total other comprehensive income (loss), net: Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net — (9,885 ) — (9,885 ) Reclassification of unrealized (gain) loss on sale of mortgage-backed and credit risk transfer securities to gain (loss) on investments, net — 1,508 — 1,508 Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense — — (25,544 ) (25,544 ) Currency translation adjustments on investment in unconsolidated venture 863 — — 863 Total other comprehensive income (loss), net 863 (8,377 ) (25,544 ) (33,058 ) AOCI balance at beginning of period 95 144,458 149,115 293,668 Other comprehensive income/(loss), net 863 (8,377 ) (25,544 ) (33,058 ) Other comprehensive income/(loss) attributable to non-controlling interest (11 ) 106 323 418 Rebalancing of ownership percentage of non-controlling interest — 1 — 1 AOCI balance at end of period 947 136,188 123,894 261,029 December 31, 2016 $ in thousands Equity method investments Available-for-sale securities Derivatives and hedging Total Total other comprehensive income (loss), net: Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net — (37,632 ) — (37,632 ) Reclassification of unrealized (gain) loss on sale of mortgage-backed and credit risk transfer securities to gain (loss) on investments, net — 6,134 — 6,134 Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense — — 5,154 5,154 Currency translation adjustments on investment in unconsolidated venture 128 — — 128 Total other comprehensive income (loss), net 128 (31,498 ) 5,154 (26,216 ) AOCI balance at beginning of period (32 ) 170,383 148,273 318,624 Other comprehensive income/(loss), net 128 (31,498 ) 5,154 (26,216 ) Other comprehensive income/(loss) attributable to non-controlling interest (1 ) 412 (63 ) 348 Rebalancing of ownership percentage of non-controlling interest — 5,161 (4,249 ) 912 AOCI balance at end of period 95 144,458 149,115 293,668
Common Dividends Declared Per Share	The following table sets forth the dividends declared per share of our common stock. Date Declared Dividends Declared Per Share Amount Date of Payment 2017 December 14, 2017 $ 0.42 January 26, 2018 September 14, 2017 $ 0.41 October 26, 2017 June 15, 2017 $ 0.40 July 26, 2017 March 15, 2017 $ 0.40 April 26, 2017 2016 December 15, 2016 $ 0.40 January 26, 2017 September 14, 2016 $ 0.40 October 26, 2016 June 15, 2016 $ 0.40 July 26, 2016 March 15, 2016 $ 0.40 April 26, 2016
Preferred Stock Dividends Declared Per Share	The following table sets forth the dividends declared per share of our Series A Preferred Stock. Date Declared Dividends Declared Per Share Amount Date of Payment 2017 December 14, 2017 $ 0.4844 January 25, 2018 September 14, 2017 $ 0.4844 October 25, 2017 June 15, 2017 $ 0.4844 July 25, 2017 March 15, 2017 $ 0.4844 April 25, 2017 2016 December 15, 2016 $ 0.4844 January 25, 2017 September 14, 2016 $ 0.4844 October 25, 2016 June 15, 2016 $ 0.4844 July 25, 2016 March 15, 2016 $ 0.4844 April 25, 2016 The following table sets forth the dividends declared per share of our Series B Preferred Stock. Date Declared Dividends Declared Per Share Amount Date of Payment 2017 September 14, 2017 $ 0.4844 December 27, 2017 June 15, 2017 $ 0.4844 September 27, 2017 March 15, 2017 $ 0.4844 June 27, 2017 2016 December 15, 2016 $ 0.4844 March 27, 2017 September 14, 2016 $ 0.4844 December 27, 2016 June 15, 2016 $ 0.4844 September 27, 2016 March 15, 2016 $ 0.4844 June 27, 2016
Schedule of Dividends Declared Per Share, Including Tax Characterization	The following table sets forth the dividends declared per share of our preferred and common stock and their related tax characterization for the fiscal tax years ended December 31, 2017 and 2016 . Tax Characterization of Dividends Fiscal Tax Year Dividends Declared Ordinary Dividends Capital Gain Distribution Carry Forward Series A Preferred Stock Dividends Fiscal tax year 2017 (1) 1.937600 1.937600 — — Fiscal tax year 2016 (2) 1.937600 1.937600 — — Series B Preferred Stock Dividends Fiscal tax year 2017 1.937600 1.937600 — — Fiscal tax year 2016 (3) 1.937600 1.937600 — — Series C Preferred Stock Dividends Fiscal tax year 2017 0.682290 0.682290 — — Common Stock Dividends Fiscal tax year 2017 1.630000 1.480040 — 0.149960 Fiscal tax year 2016 (4) 1.600000 1.857840 — — (1) Excludes preferred stock dividend of $0.4844 per share declared on December 14, 2017 having a record date of January 1, 2018, which for federal income tax purposes is a fiscal tax year 2018 dividend. (2) Excludes preferred stock dividend of $0.4844 per share declared on December 15, 2016 having a record date of January 1, 2017, which for federal income tax purposes is a fiscal tax year 2017 dividend. (3) Excludes preferred stock dividend of $0.4844 per share declared on December 15, 2016 having a record date of March 5, 2017, which for federal income tax purposes is a fiscal tax year 2017 dividend. (4) Ordinary dividends include $0.257840 of spillover dividend carried-forward from fiscal tax year 2015.

Earnings per Common Share (Tabl

Earnings per Common Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Schedule of Earnings Per Share	Earnings per share for the years ended December 31, 2017 , 2016 and 2015 is computed as follows: $ and share amounts in thousands Years Ended December 31, 2017 2016 2015 Numerator (Income) Basic Earnings: Net income (loss) available to common stockholders 320,527 231,547 89,847 Effect of dilutive securities: Income allocated to exchangeable senior notes 13,340 22,467 — Income (loss) allocated to non-controlling interest 4,450 3,287 1,344 Dilutive net income (loss) available to stockholders 338,317 257,301 91,191 Denominator (Weighted Average Shares) Basic Earnings: Shares available to common stockholders 111,610 111,973 121,378 Effect of dilutive securities: Restricted stock awards 20 20 41 Non-controlling interest OP Units 1,425 1,425 1,425 Exchangeable senior notes 9,986 16,836 — Dilutive Shares 123,041 130,254 122,844 Earnings (loss) per share: Net income (loss) attributable to common stockholders Basic 2.87 2.07 0.74 Diluted 2.75 1.98 0.74

Non-controlling Interest - Op40

Non-controlling Interest - Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2017
Noncontrolling Interest [Abstract]
Schedule of Income (Expense) Allocated and Distributions Paid to Noncontrolling Interests	The following table presents the net income (loss) allocated and distributions paid to the Operating Partnership non-controlling interest for the years ended December 31, 2017 , 2016 and 2015 . Years ended December 31, $ in thousands 2017 2016 2015 Net income (loss) allocated 4,450 3,287 1,344 Distributions paid 2,294 2,280 2,494

Summarized Quarterly Results 41

Summarized Quarterly Results of Operations (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Selected Results of Operations for Quarters	The following is a presentation of selected unaudited results of operations for the quarters ended. $ in thousands except share amounts Q4 17 Q3 17 Q2 17 Q1 17 Q4 16 Q3 16 Q2 16 Q1 16 Interest Income Mortgage-backed and credit risk transfer securities 147,509 134,138 121,027 118,873 108,871 112,467 112,860 122,246 Commercial loans 5,472 6,251 6,021 5,764 5,718 5,680 5,947 4,893 Total interest income 152,981 140,389 127,048 124,637 114,589 118,147 118,807 127,139 Interest Expense Repurchase agreements 51,955 45,907 36,072 29,947 26,048 24,892 31,260 41,800 Secured loans 5,878 5,544 4,535 3,413 2,738 2,746 2,688 2,715 Exchangeable senior notes 2,104 2,724 3,504 5,008 5,620 5,620 5,614 5,613 Total interest expense 59,937 54,175 44,111 38,368 34,406 33,258 39,562 50,128 Net interest income 93,044 86,214 82,937 86,269 80,183 84,889 79,245 77,011 Other income (loss) Gain (loss) on investments, net (17,153 ) (11,873 ) 11,175 (1,853 ) (23,402 ) (7,155 ) 1,414 11,601 Equity in earnings of unconsolidated ventures (47 ) 408 (154 ) (1,534 ) 400 729 202 1,061 Gain (loss) on derivative instruments, net 64,251 1,955 (53,513 ) 5,462 230,713 35,378 (90,363 ) (238,543 ) Realized and unrealized credit derivative income (loss), net 13,220 (2,930 ) 21,403 19,955 3,579 31,926 17,228 8,410 Net loss on extinguishment of debt (233 ) (1,344 ) (526 ) (4,711 ) — — — — Other investment income (loss), net 1,206 2,313 2,533 1,329 (1,385 ) (554 ) (2,745 ) (318 ) Total other income (loss) 61,244 (11,471 ) (19,082 ) 18,648 209,905 60,324 (74,264 ) (217,789 ) Expenses 11,972 11,254 10,635 10,885 10,745 8,555 10,957 11,549 Net income (loss) 142,316 63,489 53,220 94,032 279,343 136,658 (5,976 ) (152,327 ) Net income (loss) attributable to non-controlling interest 1,794 800 670 1,186 3,522 1,723 (75 ) (1,883 ) Net income (loss) attributable to Invesco Mortgage Capital Inc. 140,522 62,689 52,550 92,846 275,821 134,935 (5,901 ) (150,444 ) Dividends to preferred stockholders 3,086 13,562 5,716 5,716 5,716 5,716 5,716 5,716 Net income (loss) attributable to common stockholders 137,436 49,127 46,834 87,130 270,105 129,219 (11,617 ) (156,160 ) Earnings (loss) per share: Net income (loss) attributable to common stockholders Basic 1.23 0.44 0.42 0.78 2.42 1.16 (0.10 ) (1.38 ) Diluted 1.18 0.43 0.41 0.73 2.15 1.05 (0.10 ) (1.38 )

Organization and Business Ope42

Organization and Business Operations (Detail)	12 Months Ended
	Dec. 31, 2017segment
Organization And Business Operations
Ownership interest in operating partnership	98.70%
Number of operating segments	1
Minimum distribution percentage of taxable income to qualify for REIT	90.00%
Invesco Investments (Bermuda) Ltd
Organization And Business Operations
Ownership percentage in operating partnership	1.30%

Summary of Significant Accoun43

Summary of Significant Accounting Policies (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Mortgage Loans on Real Estate
Foreign currency gain (losses)	$ 4,103	$ (8,260)	$ (1,964)
Mortgage Loans on Real Estate
Mortgage Loans on Real Estate
Past due period for suspension of income recognition for residential loans	90 days
Other investment income (loss), net
Mortgage Loans on Real Estate
Foreign currency gain (losses)	$ 4,100	$ (8,200)	$ (1,900)

Variable Interest Entities - Ma

Variable Interest Entities - Maximum Risk of Loss (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Variable Interest Entity
Carrying Amount	$ 18,190,754	$ 14,981,331
Non-Agency RMBS
Variable Interest Entity
Carrying Amount	1,257,608	$ 1,995,551
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity
Carrying Amount	4,499,997
Company's Maximum Risk of Loss	4,499,997
Variable Interest Entity, Not Primary Beneficiary | CMBS
Variable Interest Entity
Carrying Amount	3,216,417
Company's Maximum Risk of Loss	3,216,417
Variable Interest Entity, Not Primary Beneficiary | Non-Agency RMBS
Variable Interest Entity
Carrying Amount	1,257,608
Company's Maximum Risk of Loss	1,257,608
Variable Interest Entity, Not Primary Beneficiary | Investments in unconsolidated ventures
Variable Interest Entity
Carrying Amount	25,972
Company's Maximum Risk of Loss	$ 25,972

Variable Interest Entities - Ad

Variable Interest Entities - Additional Information (Detail) $ in Thousands	Dec. 09, 2015USD ($)
Variable Interest Entity Disclosure [Abstract]
Proceeds from sale of certain beneficial interests in residential securitizations	$ 69,000
Gain (loss) on deconsolidation of VIEs, net	$ (19,623)

Variable Interest Entities - Ga

Variable Interest Entities - Gain (Loss) On Deconsolidation of VIEs (Details) $ in Thousands	Dec. 09, 2015USD ($)
Variable Interest Entity Disclosure [Abstract]
Gain (loss) related to derecognition of Residential Securitizations, net	$ (13,260)
Gain (loss) related to remeasurement of retained interest, net	3,068
Gain (loss) on sale of the securities, net	(9,431)
Total gain (loss) on deconsolidation of VIEs, net	$ (19,623)

Variable Interest Entities - Im

Variable Interest Entities - Impact of Deconsolidation on Financial Statements (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity
Interest income - Residential loans	[1]									$ 0	$ 0	$ 110,908
Interest expense - Asset-backed securities	[1]									0	0	82,041
Net interest income		$ 93,044	$ 86,214	$ 82,937	$ 86,269	$ 80,183	$ 84,889	$ 79,245	$ 77,011	348,464	321,328	372,159
Reduction in provision for loan losses										0	0	(213)
Net interest income after reduction in provision for loan losses										348,464	321,328	372,372
Expenses - Consolidated securitization trusts	[1]									0	0	8,219
Net income		$ 142,316	$ 63,489	$ 53,220	$ 94,032	$ 279,343	$ 136,658	$ (5,976)	$ (152,327)	$ 353,057	$ 257,698	114,055
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity
Interest income - Residential loans												110,908
Interest expense - Asset-backed securities												82,041
Net interest income												28,867
Reduction in provision for loan losses												(213)
Net interest income after reduction in provision for loan losses												29,080
Expenses - Consolidated securitization trusts												8,219
Net income												$ 20,861
[1]	The consolidated statement of operations for the year ended December 31, 2015 includes income and expenses of consolidated variable interest entities ("VIEs"). We deconsolidated these VIEs in 2015. Refer to Note 2 - “Summary of Significant Accounting Policies” for further discussion.

Mortgage-Backed and Credit Ri48

Mortgage-Backed and Credit Risk Transfer Securities - Summary of Investment Portfolio (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 20,855,353	$ 18,275,563
Unamortized Premium (Discount)	(2,840,992)	(3,456,795)
Amortized Cost	18,014,361	14,818,768
Unrealized Gain/ (Loss), net	176,393	162,563
Fair Value	$ 18,190,754	$ 14,981,331
Net Weighted Average Coupon	3.23%	3.05%
Period- end Weighted Average Yield	3.42%	3.05%
Quarterly Weighted Average Yield	3.27%	2.87%
Percentage of agency collateralized mortgage obligations interest only securities, principal balance	81.80%	85.50%
Percentage of agency collateralized mortgage obligations interest only securities, amortized cost	20.90%	26.80%
Percentage of agency collateralized mortgage obligations interest only securities, fair value	18.70%	27.10%
Unamortized premium (discount) non-accretable portion	$ 195,300	$ 252,500
Percentage of Non-Agency RMBS interest-only, principal balance	51.50%	43.50%
Percentage of Non-Agency RMBS interest-only, amortized cost	2.00%	1.50%
Percentage of Non-Agency RMBS interest only, fair value	1.80%	1.30%
Percentage of government sponsored enterprise credit risk transfer securities	26.70%	19.20%
Percentage of CMBS interest only, principal balance	15.80%	20.30%
Percentage of CMBS interest only, amortized cost	0.50%	0.80%
Percentage of CMBS interest only, fair value	0.60%	0.90%
On or After September 1, 2016
Schedule of Available-for-sale Securities
Fair value option, percentage of RMBS, principal balance	42.30%	4.30%
Fair value option, percentage of RMBS, amortized cost	42.00%	4.30%
Fair value option, percentage of RMBS, fair value	42.20%	4.20%
Fair value option, percentage of CMBS, principal balance	25.40%	0.40%
Fair value option, percentage of CMBS, amortized cost	26.70%	0.60%
Fair value option, percentage of CMBS, fair value	26.10%	0.50%
Agency RMBS
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 12,206,152	$ 8,966,483
Unamortized Premium (Discount)	442,772	381,927
Amortized Cost	12,648,924	9,348,410
Unrealized Gain/ (Loss), net	(73,017)	(26,591)
Fair Value	$ 12,575,907	$ 9,321,819
Net Weighted Average Coupon	3.40%	3.37%
Period- end Weighted Average Yield	2.79%	2.42%
Quarterly Weighted Average Yield	2.58%	2.20%
Agency RMBS | 15 year fixed-rate
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 2,917,307	$ 3,460,625
Unamortized Premium (Discount)	119,120	151,526
Amortized Cost	3,036,427	3,612,151
Unrealized Gain/ (Loss), net	(61,645)	(54,223)
Fair Value	$ 2,974,782	$ 3,557,928
Net Weighted Average Coupon	3.08%	3.11%
Period- end Weighted Average Yield	2.17%	2.19%
Quarterly Weighted Average Yield	1.98%	1.99%
Agency RMBS | 30 year fixed-rate
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 7,354,211	$ 2,780,806
Unamortized Premium (Discount)	295,977	185,521
Amortized Cost	7,650,188	2,966,327
Unrealized Gain/ (Loss), net	(9,648)	15,390
Fair Value	$ 7,640,540	$ 2,981,717
Net Weighted Average Coupon	3.72%	4.37%
Period- end Weighted Average Yield	3.09%	2.61%
Quarterly Weighted Average Yield	2.90%	2.57%
Agency RMBS | ARM
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 238,486	$ 301,900
Unamortized Premium (Discount)	1,609	2,520
Amortized Cost	240,095	304,420
Unrealized Gain/ (Loss), net	1,105	3,453
Fair Value	$ 241,200	$ 307,873
Net Weighted Average Coupon	2.67%	2.69%
Period- end Weighted Average Yield	2.60%	2.59%
Quarterly Weighted Average Yield	2.36%	2.16%
Agency RMBS | Hybrid ARM
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 1,696,148	$ 2,423,152
Unamortized Premium (Discount)	26,066	42,360
Amortized Cost	1,722,214	2,465,512
Unrealized Gain/ (Loss), net	(2,829)	8,789
Fair Value	$ 1,719,385	$ 2,474,301
Net Weighted Average Coupon	2.70%	2.70%
Period- end Weighted Average Yield	2.54%	2.52%
Quarterly Weighted Average Yield	2.25%	2.02%
Agency-CMO
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 1,226,539	$ 1,712,120
Unamortized Premium (Discount)	(942,290)	(1,368,916)
Amortized Cost	284,249	343,204
Unrealized Gain/ (Loss), net	(10,306)	837
Fair Value	$ 273,943	$ 344,041
Net Weighted Average Coupon	2.05%	2.16%
Period- end Weighted Average Yield	2.91%	3.08%
Quarterly Weighted Average Yield	2.74%	2.07%
Non-Agency RMBS
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 2,785,704	$ 3,838,314
Unamortized Premium (Discount)	(1,661,683)	(1,934,269)
Amortized Cost	1,124,021	1,904,045
Unrealized Gain/ (Loss), net	133,587	91,506
Fair Value	$ 1,257,608	$ 1,995,551
Net Weighted Average Coupon	2.08%	2.21%
Period- end Weighted Average Yield	7.19%	5.22%
Quarterly Weighted Average Yield	7.18%	5.22%
Non-Agency RMBS | Variable Rate
Schedule of Available-for-sale Securities
Percentage of non-agency securities classified as variable rate	52.20%	45.50%
Non-Agency RMBS | Fixed Rate
Schedule of Available-for-sale Securities
Percentage of non-agency securities classified as fixed rate	37.80%	47.20%
Non-Agency RMBS | Floating Rate
Schedule of Available-for-sale Securities
Percentage of non-agency securities classified as floating rate	10.00%	7.30%
GSE CRT
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 757,183	$ 707,899
Unamortized Premium (Discount)	24,306	24,320
Amortized Cost	781,489	732,219
Unrealized Gain/ (Loss), net	85,390	35,981
Fair Value	$ 866,879	$ 768,200
Net Weighted Average Coupon	3.41%	2.38%
Period- end Weighted Average Yield	2.45%	1.51%
Quarterly Weighted Average Yield	2.79%	1.24%
CMBS
Schedule of Available-for-sale Securities
Principal/ Notional Balance	$ 3,879,775	$ 3,050,747
Unamortized Premium (Discount)	(704,097)	(559,857)
Amortized Cost	3,175,678	2,490,890
Unrealized Gain/ (Loss), net	40,739	60,830
Fair Value	$ 3,216,417	$ 2,551,720
Net Weighted Average Coupon	3.85%	3.80%
Period- end Weighted Average Yield	4.92%	4.21%
Quarterly Weighted Average Yield	4.77%	4.17%

Mortgage-Backed and Credit Ri49

Mortgage-Backed and Credit Risk Transfer Securities - Components of Non-Agency RMBS Portfolio By Asset Type (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Mortgage-backed and credit risk transfer securities, at fair value	$ 18,190,754	$ 14,981,331
Non-Agency
Schedule of Available-for-sale Securities
Mortgage-backed and credit risk transfer securities, at fair value	$ 1,257,608	$ 1,995,551
Percentage of Non-Agency	100.00%	100.00%
Non-Agency | Prime
Schedule of Available-for-sale Securities
Mortgage-backed and credit risk transfer securities, at fair value	$ 649,671	$ 889,658
Percentage of Non-Agency	51.60%	44.60%
Non-Agency | Alt-A
Schedule of Available-for-sale Securities
Mortgage-backed and credit risk transfer securities, at fair value	$ 393,899	$ 447,213
Percentage of Non-Agency	31.30%	22.40%
Non-Agency | Re-REMIC
Schedule of Available-for-sale Securities
Mortgage-backed and credit risk transfer securities, at fair value	$ 173,110	$ 364,301
Percentage of Non-Agency	13.70%	18.20%
Non-Agency | Subprime/reperforming
Schedule of Available-for-sale Securities
Mortgage-backed and credit risk transfer securities, at fair value	$ 40,928	$ 294,379
Percentage of Non-Agency	3.40%	14.80%

Mortgage-Backed and Credit Ri50

Mortgage-Backed and Credit Risk Transfer Securities - Components of Senior Re-REMIC at Fair Value (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	100.00%	100.00%
Percentage, Re-REMIC holdings that are not senior class	57.50%
0% - 10%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	34.50%	17.60%
10% - 20%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	3.70%	7.40%
20% - 30%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	12.30%	13.50%
30% - 40%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	18.40%	15.70%
40% - 50%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	9.60%	27.00%
50% - 60%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	19.70%	16.10%
60% - 70%
Schedule of Available-for-sale Securities
Percentage of Re-REMIC holdings at fair value	1.80%	2.70%

Mortgage-Backed and Credit Ri51

Mortgage-Backed and Credit Risk Transfer Securities - Components of Carrying Value of Investment Portfolio (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Principal/ notional balance	$ 20,855,353	$ 18,275,563
Unamortized premium	521,626	476,314
Unamortized discount	(3,362,618)	(3,933,109)
Gross unrealized gains	341,656	302,099
Gross unrealized losses	(165,263)	(139,536)
Fair Value	$ 18,190,754	$ 14,981,331

Mortgage-Backed and Credit Ri52

Mortgage-Backed and Credit Risk Transfer Securities - Fair Value of MBS and GSE CRTs According to Weighted Average Life Classification (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Less than one year	$ 135,559	$ 121,076
Greater than one year and less than five years	7,934,836	6,719,923
Greater than or equal to five years	10,120,359	8,140,332
Total	$ 18,190,754	$ 14,981,331

Mortgage-Backed and Credit Ri53

Mortgage-Backed and Credit Risk Transfer Securities - Unrealized Losses and Estimated Fair Value of MBS and GSE CRT by Length of Time (Detail) $ in Thousands	Dec. 31, 2017USD ($)security	Dec. 31, 2016USD ($)security
Fair Value
Less than 12 Months	$ 5,556,381	$ 5,858,500
12 Months or More	4,200,600	1,218,879
Total	9,756,981	7,077,379
Unrealized Losses
Less than 12 Months	(54,896)	(110,569)
12 Months or More	(110,367)	(28,967)
Total	$ (165,263)	$ (139,536)
Number of Securities
Less than 12 Months (in securities) | security	358	386
12 Months or More (in securities) | security	264	95
Total (in securities) | security	622	481
Agency RMBS
Fair Value
Less than 12 Months	$ 4,504,090	$ 5,006,723
12 Months or More	3,887,210	615,070
Total	8,391,300	5,621,793
Unrealized Losses
Less than 12 Months	(26,142)	(92,163)
12 Months or More	(102,534)	(19,571)
Total	$ (128,676)	$ (111,734)
Number of Securities
Less than 12 Months (in securities) | security	218	280
12 Months or More (in securities) | security	236	47
Total (in securities) | security	454	327
Fair value option, fair value	$ 3,400,000	$ 149,700
Fair value option, unrealized losses	22,800	4,000
Agency RMBS | 15 year fixed-rate
Fair Value
Less than 12 Months	111,020	2,781,777
12 Months or More	2,406,021	65,964
Total	2,517,041	2,847,741
Unrealized Losses
Less than 12 Months	(321)	(66,506)
12 Months or More	(67,285)	(1,556)
Total	$ (67,606)	$ (68,062)
Number of Securities
Less than 12 Months (in securities) | security	26	127
12 Months or More (in securities) | security	133	17
Total (in securities) | security	159	144
Agency RMBS | 30 year fixed-rate
Fair Value
Less than 12 Months	$ 3,677,576	$ 747,719
12 Months or More	963,547	547,763
Total	4,641,123	1,295,482
Unrealized Losses
Less than 12 Months	(20,730)	(15,409)
12 Months or More	(27,158)	(18,004)
Total	$ (47,888)	$ (33,413)
Number of Securities
Less than 12 Months (in securities) | security	107	45
12 Months or More (in securities) | security	56	27
Total (in securities) | security	163	72
Agency RMBS | ARM
Fair Value
Less than 12 Months	$ 101,173	$ 120,540
12 Months or More	0	1,091
Total	101,173	121,631
Unrealized Losses
Less than 12 Months	(902)	(326)
12 Months or More	0	(7)
Total	$ (902)	$ (333)
Number of Securities
Less than 12 Months (in securities) | security	12	9
12 Months or More (in securities) | security	0	1
Total (in securities) | security	12	10
Agency RMBS | Hybrid ARM
Fair Value
Less than 12 Months	$ 614,321	$ 1,356,687
12 Months or More	517,642	252
Total	1,131,963	1,356,939
Unrealized Losses
Less than 12 Months	(4,189)	(9,922)
12 Months or More	(8,091)	(4)
Total	$ (12,280)	$ (9,926)
Number of Securities
Less than 12 Months (in securities) | security	73	99
12 Months or More (in securities) | security	47	2
Total (in securities) | security	120	101
Agency-CMO
Fair Value
Less than 12 Months	$ 75,299	$ 163,114
12 Months or More	81,988	22,792
Total	157,287	185,906
Unrealized Losses
Less than 12 Months	(10,433)	(3,812)
12 Months or More	(2,309)	(952)
Total	$ (12,742)	$ (4,764)
Number of Securities
Less than 12 Months (in securities) | security	44	28
12 Months or More (in securities) | security	5	3
Total (in securities) | security	49	31
Agency IO
Number of Securities
Fair value option, unrealized losses		$ 3,000
CMO
Number of Securities
Fair value option, unrealized losses	$ 2,700	1,700
Non-Agency RMBS
Fair Value
Less than 12 Months	84,439	287,647
12 Months or More	96,263	497,863
Total	180,702	785,510
Unrealized Losses
Less than 12 Months	(709)	(7,861)
12 Months or More	(1,732)	(6,671)
Total	$ (2,441)	$ (14,532)
Number of Securities
Less than 12 Months (in securities) | security	15	42
12 Months or More (in securities) | security	11	36
Total (in securities) | security	26	78
GSE CRT
Fair Value
Less than 12 Months		$ 0
12 Months or More		35,935
Total		35,935
Unrealized Losses
Less than 12 Months		0
12 Months or More		(969)
Total		$ (969)
Number of Securities
Less than 12 Months (in securities) | security		0
12 Months or More (in securities) | security		3
Total (in securities) | security		3
CMBS
Fair Value
Less than 12 Months	$ 892,553	$ 401,016
12 Months or More	135,139	47,219
Total	1,027,692	448,235
Unrealized Losses
Less than 12 Months	(17,612)	(6,733)
12 Months or More	(3,792)	(804)
Total	$ (21,404)	$ (7,537)
Number of Securities
Less than 12 Months (in securities) | security	81	36
12 Months or More (in securities) | security	12	6
Total (in securities) | security	93	42
Fair value option, fair value	$ 596,000	$ 13,900
Fair value option, unrealized losses	$ 8,900	$ 613

Mortgage-Backed and Credit Ri54

Mortgage-Backed and Credit Risk Transfer Securities - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Gross unrealized losses	$ 165,263	$ 139,536
Agency RMBS
Schedule of Available-for-sale Securities
Gross unrealized losses	128,700
Fair value option, unrealized losses	22,800	4,000
CMO
Schedule of Available-for-sale Securities
Gross unrealized losses	(10,100)
Fair value option, unrealized losses	2,700	$ 1,700
Agency-IO, Non-Agency RMBS, GSE CRT and CMBS
Schedule of Available-for-sale Securities
Gross unrealized losses	$ 33,900

Mortgage-Backed and Credit Ri55

Mortgage-Backed and Credit Risk Transfer Securities - OTTI included in earnings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Other-than-temporary credit impairment losses	$ 11,962	$ 8,909	$ 0
RMBS interest-only securities
Schedule of Available-for-sale Securities
Other-than-temporary credit impairment losses	11,208	8,334
Non-Agency RMBS
Schedule of Available-for-sale Securities
Other-than-temporary credit impairment losses	$ 754	$ 575

Mortgage-Backed and Credit Ri56

Mortgage-Backed and Credit Risk Transfer Securities - Realized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Dec. 09, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Amount of MBS and GSE CRT are accounted for under the fair value option		$ 6,500,000	$ 427,500
Percentage of MBS and GSE CRT are accounted for under the fair value option		35.60%	2.90%
Gross realized gains on sale of investments		$ 2,208	$ 14,196	$ 13,346
Gross realized losses on sale of investments		(3,873)	(21,635)	(11,114)
Other-than-temporary impairment losses		(11,962)	(8,909)	0
Net unrealized gains and losses on trading securities		22	(1)	0
Total gain (loss) on investments, net		(19,704)	(17,542)	1,618
Gain (loss) on deconsolidation of VIEs, net	$ (19,623)
MBS
Schedule of Available-for-sale Securities
Net unrealized gains and losses on securities accounted for under the fair value option		(21,368)	(5,791)	(558)
GSE CRT
Schedule of Available-for-sale Securities
Net unrealized gains and losses on securities accounted for under the fair value option		$ 15,269	$ 4,598	$ (56)

Mortgage-Backed and Credit Ri57

Mortgage-Backed and Credit Risk Transfer Securities - Components of MBS and GSE CRT Interest Income (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities
Coupon Interest									$ 616,697	$ 574,692	$ 641,181
Net (Premium Amortization)/Discount Accretion									(95,150)	(118,248)	(117,288)
Interest Income	$ 147,509	$ 134,138	$ 121,027	$ 118,873	$ 108,871	$ 112,467	$ 112,860	$ 122,246	521,547	456,444	523,893
Agency
Schedule of Available-for-sale Securities
Coupon Interest									392,248	346,783	372,610
Net (Premium Amortization)/Discount Accretion									(107,702)	(116,991)	(121,170)
Interest Income									284,546	229,792	251,440
CMBS
Schedule of Available-for-sale Securities
Coupon Interest									131,005	122,636	149,977
Net (Premium Amortization)/Discount Accretion									(4,268)	(11,536)	(11,322)
Interest Income									126,737	111,100	138,655
Non-Agency
Schedule of Available-for-sale Securities
Coupon Interest									70,849	94,206	110,885
Net (Premium Amortization)/Discount Accretion									18,769	13,529	18,287
Interest Income									89,618	107,735	129,172
GSE CRT
Schedule of Available-for-sale Securities
Coupon Interest									22,164	9,575	6,681
Net (Premium Amortization)/Discount Accretion									(1,949)	(3,192)	(3,088)
Interest Income									20,215	6,383	3,593
Other
Schedule of Available-for-sale Securities
Coupon Interest									431	1,492	1,028
Net (Premium Amortization)/Discount Accretion									0	(58)	5
Interest Income									$ 431	$ 1,434	$ 1,033

Commercial Loans Held-for-Inv58

Commercial Loans Held-for-Investment (Details)	12 Months Ended
	Dec. 31, 2017USD ($)loan	Dec. 31, 2016USD ($)loan
Mortgage Loans on Real Estate
Carrying value	$ 191,808,000	$ 273,355,000
Commercial Portfolio Segment | Mezzanine Loan
Mortgage Loans on Real Estate
Number of loans | loan	8	10
Principal Balance	$ 191,894,000	$ 273,666,000
Unamortized (fees)/ costs, net	(86,000)	(311,000)
Carrying value	$ 191,808,000	$ 273,355,000
Weighted Average Coupon	8.52%	8.14%
Weighted Average Years to Maturity	1 year 2 months 12 days	1 year 7 months 6 days
Allowance for loan losses	$ 0

Other Assets (Details)

Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule of Investments [Abstract]
FHLBI stock	$ 74,250	$ 74,250
Investments in unconsolidated ventures	25,972	33,301
Investment in exchange-traded fund	3,979	500
Prepaid expenses and other assets	1,379	1,246
Total	$ 105,580	$ 109,297

Borrowings - Schedule of Borrow

Borrowings - Schedule of Borrowings (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Repurchase Agreements
Amount Outstanding	$ 14,080,801	$ 11,160,669
Weighted Average Interest Rate	1.82%	1.23%
Weighted Average Remaining Maturity (Days)	25 days	30 days
Secured Loans:
Secured loans, amount outstanding	$ 1,650,000	$ 1,650,000
Total Borrowings
Exchangeable senior notes, carrying value	143,231	397,041
Secured Debt, Excluding Asset-backed Securities
Total Borrowings
Total borrowings, amount outstanding	$ 15,874,211	$ 13,210,669
Total borrowings, weighted average interest rate	1.82%	1.28%
Total borrowings, weighted average remaining maturity (days)	263 days	373 days
Agency RMBS
Repurchase Agreements
Amount Outstanding	$ 11,111,755	$ 8,148,220
Weighted Average Interest Rate	1.58%	0.93%
Weighted Average Remaining Maturity (Days)	25 days	32 days
CMBS
Repurchase Agreements
Amount Outstanding	$ 1,396,330	$ 944,718
Weighted Average Interest Rate	2.61%	1.86%
Weighted Average Remaining Maturity (Days)	9 days	16 days
Non-Agency RMBS
Repurchase Agreements
Amount Outstanding	$ 915,225	$ 1,519,859
Weighted Average Interest Rate	2.77%	2.06%
Weighted Average Remaining Maturity (Days)	31 days	28 days
GSE CRT
Repurchase Agreements
Amount Outstanding	$ 657,491	$ 547,872
Weighted Average Interest Rate	2.78%	2.25%
Weighted Average Remaining Maturity (Days)	24 days	16 days
Secured Loans
Secured Loans:
Secured loans, amount outstanding	$ 1,650,000	$ 1,650,000
Secured loans, weighted average interest rate	1.52%	0.74%
Secured loans, weighted average remaining maturity (days)	2317 days	2682 days
Exchangeable Senior Notes
Exchangeable Senior Notes
Exchangeable senior notes, amount outstanding	$ 143,410	$ 400,000
Exchangeable senior notes, weighted average interest rate	5.00%	5.00%
Exchangeable senior notes, weighted average remaining maturity (days)	74 days	439 days
Total Borrowings
Debt issuance costs	$ 200	$ 3,000

Borrowings - Schedule of Maturi

Borrowings - Schedule of Maturities (Details) $ in Thousands	Dec. 31, 2017USD ($)
Debt Disclosure [Abstract]
2,018	$ 14,224,211
2,019	0
2,020	300,000
2,021	100,000
2,022	0
Thereafter	1,250,000
Total	$ 15,874,211

Borrowings - Repurchase Agreeme

Borrowings - Repurchase Agreements (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)Counterparty	Dec. 31, 2016USD ($)Counterparty
Repurchase Agreement Counterparty
Amount Outstanding	$ 14,080,801	$ 11,160,669
Advances from FHLBI	1,650,000	1,650,000
Total, Amount outstanding	$ 15,730,801	$ 12,810,669
Percent of Total Amount Outstanding	89.50%	87.10%
Percent of Advances from FHLBI	10.50%	12.90%
Total, Percent of total amount outstanding	100.00%	100.00%
MBS and GSE CRT Pledged as Collateral	$ 15,523,415	$ 12,444,304
MBS and GSE CRT Pledged as Collateral, Advances from FHLBI	1,927,496	1,931,582
Total, MBS and GSE CRT Pledged as Collateral	$ 17,450,911	$ 14,375,886
Number of counterparties | Counterparty	7	6
HSBC
Repurchase Agreement Counterparty
Amount Outstanding	$ 1,745,684	$ 1,401,966
Percent of Total Amount Outstanding	11.20%	11.20%
MBS and GSE CRT Pledged as Collateral	$ 1,839,411	$ 1,468,793
ING Financial Markets
Repurchase Agreement Counterparty
Amount Outstanding	$ 1,482,603	$ 1,142,200
Percent of Total Amount Outstanding	9.40%	8.90%
MBS and GSE CRT Pledged as Collateral	$ 1,571,061	$ 1,216,492
RBC
Repurchase Agreement Counterparty
Amount Outstanding	$ 1,144,856	$ 1,098,631
Percent of Total Amount Outstanding	7.30%	8.60%
MBS and GSE CRT Pledged as Collateral	$ 1,375,285	$ 1,293,336
Industrial and Commercial Bank of China
Repurchase Agreement Counterparty
Amount Outstanding	$ 1,038,844	$ 707,616
Percent of Total Amount Outstanding	6.60%	5.50%
MBS and GSE CRT Pledged as Collateral	$ 1,102,543	$ 748,503
E D & F Man Capital Markets
Repurchase Agreement Counterparty
Amount Outstanding	$ 1,028,437	$ 405,615
Percent of Total Amount Outstanding	6.50%	3.20%
MBS and GSE CRT Pledged as Collateral	$ 1,085,429	$ 430,896
Mirae Asset Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 958,756
Percent of Total Amount Outstanding	6.10%
MBS and GSE CRT Pledged as Collateral	$ 1,018,664
MUFG Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 865,201	$ 703,382
Percent of Total Amount Outstanding	5.50%	5.50%
MBS and GSE CRT Pledged as Collateral	$ 936,071	$ 740,404
Citigroup
Repurchase Agreement Counterparty
Amount Outstanding	$ 724,094	$ 427,185
Percent of Total Amount Outstanding	4.60%	3.30%
MBS and GSE CRT Pledged as Collateral	$ 841,977	$ 534,875
Amherst Pierpont Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 722,080	$ 681,853
Percent of Total Amount Outstanding	4.60%	5.30%
MBS and GSE CRT Pledged as Collateral	$ 764,713	$ 717,663
KGS-Alpha Capital Markets
Repurchase Agreement Counterparty
Amount Outstanding	$ 461,098	$ 441,541
Percent of Total Amount Outstanding	2.90%	3.40%
MBS and GSE CRT Pledged as Collateral	$ 491,313	$ 475,858
JP Morgan
Repurchase Agreement Counterparty
Amount Outstanding	$ 451,941	$ 477,947
Percent of Total Amount Outstanding	2.90%	3.70%
MBS and GSE CRT Pledged as Collateral	$ 523,590	$ 554,494
Societe Generale
Repurchase Agreement Counterparty
Amount Outstanding	$ 386,737	$ 325,393
Percent of Total Amount Outstanding	2.50%	2.50%
MBS and GSE CRT Pledged as Collateral	$ 495,093	$ 427,200
BNP Paribas Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 348,340	$ 307,641
Percent of Total Amount Outstanding	2.20%	2.40%
MBS and GSE CRT Pledged as Collateral	$ 388,091	$ 346,484
South Street Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 332,623	$ 675,660
Percent of Total Amount Outstanding	2.10%	5.30%
MBS and GSE CRT Pledged as Collateral	$ 354,689	$ 713,330
Goldman Sachs
Repurchase Agreement Counterparty
Amount Outstanding	$ 324,152	$ 486,430
Percent of Total Amount Outstanding	2.10%	3.80%
MBS and GSE CRT Pledged as Collateral	$ 419,713	$ 623,400
Mizuho Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 310,835
Percent of Total Amount Outstanding	2.00%
MBS and GSE CRT Pledged as Collateral	$ 330,555
Guggenheim Liquidity Services
Repurchase Agreement Counterparty
Amount Outstanding	$ 306,081	$ 356,149
Percent of Total Amount Outstanding	1.90%	2.80%
MBS and GSE CRT Pledged as Collateral	$ 322,452	$ 377,030
Bank of Nova Scotia
Repurchase Agreement Counterparty
Amount Outstanding	$ 289,705	$ 479,105
Percent of Total Amount Outstanding	1.80%	3.70%
MBS and GSE CRT Pledged as Collateral	$ 301,715	$ 500,578
Natixis Securities
Repurchase Agreement Counterparty
Amount Outstanding	$ 275,764	$ 336,202
Percent of Total Amount Outstanding	1.80%	2.60%
MBS and GSE CRT Pledged as Collateral	$ 302,291	$ 362,432
All other repurchase agreement counterparties
Repurchase Agreement Counterparty
Amount Outstanding	$ 882,970	$ 706,153
Percent of Total Amount Outstanding	5.50%	5.40%
MBS and GSE CRT Pledged as Collateral	$ 1,058,759	$ 912,536

Borrowings - Additional Informa

Borrowings - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2013
Repurchase Agreement Counterparty
Collateral ratio	110.00%	112.00%
Exchangeable Senior Notes
Repurchase Agreement Counterparty
Aggregate principal balance			$ 400,000,000
Debt instrument, percentage	5.00%
Accrued interest payable on notes	$ 2,100,000	$ 5,900,000
Exchangeable Senior Notes
Repurchase Agreement Counterparty
Exchangeable senior notes, amount outstanding	$ 143,410,000	$ 400,000,000
Minimum
Repurchase Agreement Counterparty
Repurchase obligation maturity	1 month
Maximum
Repurchase Agreement Counterparty
Repurchase obligation maturity	12 months
Federal Home Loan Bank of Indianapolis
Repurchase Agreement Counterparty
Outstanding secured advances from FHLBI	$ 1,650,000,000
Average outstanding borrowings from FHLBI	$ 1,650,000,000
FHLBI weighted average interest rate on advances	1.17%
FHLBI weighted average maturity of advances	6 years 4 months

Borrowings - Schedule of Retire

Borrowings - Schedule of Retirements of Exchangeable Senior Notes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Reacquisition price									$ 262,069	$ 0	$ 0
Net loss on extinguishment of debt	$ 233	$ 1,344	$ 526	$ 4,711	$ 0	$ 0	$ 0	$ 0	6,814	$ 0	$ 0
Exchangeable Senior Notes
Debt Instrument [Line Items]
Reacquisition price									262,069
Par value of Notes retired									(256,590)
Write off of unamortized debt issuance cost associated with Notes retired									1,335
Net loss on extinguishment of debt									$ 6,814

Collateral Positions (Details)

Collateral Positions (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Repurchase agreement collateral pledged	$ 15,523,415,000	$ 12,444,304,000
Secured loans collateral pledged	1,927,496,000	1,931,582,000
Total collateral pledged	17,475,236,000	14,508,648,000
Cash collateral held	7,327,000	1,700,000
Non-cash collateral held	0	536,000
Total collateral held	7,327,000	2,236,000
Interest Rate Swaps
Derivative [Line Items]
Interest rate swaps collateral pledged	24,325,000	132,762,000
Agency RMBS
Derivative [Line Items]
Repurchase agreement collateral pledged	11,788,765,000	8,654,233,000
Secured loans collateral pledged	623,181,000	585,504,000
Agency RMBS | Interest Rate Swaps
Derivative [Line Items]
Interest rate swaps collateral pledged	23,705,000	46,312,000
CMBS
Derivative [Line Items]
Repurchase agreement collateral pledged	1,737,831,000	1,168,309,000
Secured loans collateral pledged	1,304,315,000	1,346,078,000
Non-Agency RMBS
Derivative [Line Items]
Repurchase agreement collateral pledged	1,143,373,000	1,887,550,000
GSE CRT
Derivative [Line Items]
Repurchase agreement collateral pledged	853,446,000	734,212,000
Mortgage-backed and GSE CRT securities
Derivative [Line Items]
Total collateral pledged	17,474,616,000	14,422,198,000
Cash
Derivative [Line Items]
Total collateral pledged	620,000	86,450,000
Cash | Currency Forward Contracts
Derivative [Line Items]
Interest rate swaps collateral pledged	$ 620,000	0
Cash | Interest Rate Swaps
Derivative [Line Items]
Interest rate swaps collateral pledged		$ 86,450,000

Derivatives and Hedging Activ66

Derivatives and Hedging Activities - Outstanding Interest Rate Swaptions and Derivative Instrument Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)
Changes in notional amount of derivative instruments [Roll Forward]
Notional Amount as of January 1, 2017	$ 7,132,274,000
Additions	2,904,328,000
Settlement, Termination, Expiration or Exercise	(286,250,000)
Notional Amount as of December 31, 2017	9,750,352,000
Interest Rate Swaps
Changes in notional amount of derivative instruments [Roll Forward]
Notional Amount as of January 1, 2017	6,500,000,000
Additions	2,620,000,000
Settlement, Termination, Expiration or Exercise	0
Notional Amount as of December 31, 2017	9,120,000,000
Currency Forward Contracts
Changes in notional amount of derivative instruments [Roll Forward]
Notional Amount as of January 1, 2017	62,308,000
Additions	284,328,000
Settlement, Termination, Expiration or Exercise	(269,777,000)
Notional Amount as of December 31, 2017	76,859,000
Credit Derivatives
Changes in notional amount of derivative instruments [Roll Forward]
Notional Amount as of January 1, 2017	569,966,000
Additions	0
Settlement, Termination, Expiration or Exercise	(16,473,000)
Notional Amount as of December 31, 2017	$ 553,493,000

Derivatives and Hedging Activ67

Derivatives and Hedging Activities - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosures
Reclassification as (decrease) increase to interest expense	$ 25,544,000	$ (5,154,000)	$ (66,757,000)
Loss to be reclassified during the next 12 months	25,800,000
Accumulated other comprehensive income	261,029,000	293,668,000
Realized loss on derivative instruments, net	(67,838,000)	57,943,000	44,272,000
Notional amount	9,750,352,000	7,132,274,000
Derivative liabilities, at fair value	22,445,000	134,228,000
Mortgage-backed and credit risk transfer securities, pledged as collateral	17,474,616,000	14,422,198,000
Accrued Interest
Derivative Instruments and Hedging Activities Disclosures
Derivative liabilities, at fair value	21,700,000
Agency RMBS
Derivative Instruments and Hedging Activities Disclosures
Mortgage-backed and credit risk transfer securities, pledged as collateral	23,700,000
Interest Rate Swaps
Derivative Instruments and Hedging Activities Disclosures
Notional amount	9,120,000,000	6,500,000,000
Derivative liabilities, at fair value	31,548,000	133,833,000
Currency Forward Contracts
Derivative Instruments and Hedging Activities Disclosures
Notional amount	76,859,000	62,308,000
Derivative liabilities, at fair value	1,217,000	395,000
Derivatives and hedging
Derivative Instruments and Hedging Activities Disclosures
Reclassification as (decrease) increase to interest expense	25,544,000	(5,154,000)
Accumulated other comprehensive income	123,900,000	149,100,000
Not Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures
Realized loss on derivative instruments, net	(67,838,000)	57,943,000	44,272,000
Not Designated as Hedging Instrument | Interest Rate Swaps
Derivative Instruments and Hedging Activities Disclosures
Realized loss on derivative instruments, net	(72,894,000)	69,090,000	31,881,000
Not Designated as Hedging Instrument | Currency Forward Contracts
Derivative Instruments and Hedging Activities Disclosures
Realized loss on derivative instruments, net	5,056,000	(12,632,000)	$ (1,172,000)
Pound Sterling | Currency Forward Contracts
Derivative Instruments and Hedging Activities Disclosures
Notional amount	49,700,000	49,000,000
Euro | Currency Forward Contracts
Derivative Instruments and Hedging Activities Disclosures
Notional amount	27,200,000	$ 13,300,000
Central Clearing Counterparty
Derivative Instruments and Hedging Activities Disclosures
Derivative liabilities, at fair value	$ 10,300,000

Derivatives and Hedging Activ68

Derivatives and Hedging Activities - Interest Rate Derivatives Outstanding (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Interest Rate Derivatives Outstanding
Notional	$ 9,750,352,000	$ 7,132,274,000
Interest Rate Swaps
Interest Rate Derivatives Outstanding
Notional	$ 9,120,000,000	$ 6,500,000,000
Fixed Interest Rate in Contract	2.13246%
Interest Rate Swaps | ING Capital Markets LLC
Interest Rate Derivatives Outstanding
Notional	$ 350,000,000
Fixed Interest Rate in Contract	0.954%
Interest Rate Swaps | UBS AG
Interest Rate Derivatives Outstanding
Notional	$ 500,000,000
Fixed Interest Rate in Contract	1.102%
Interest Rate Swaps | ING Capital Markets LLC
Interest Rate Derivatives Outstanding
Notional	$ 400,000,000
Fixed Interest Rate in Contract	0.8675%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 300,000,000
Fixed Interest Rate in Contract	2.496%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 300,000,000
Fixed Interest Rate in Contract	2.691%
Interest Rate Swaps | Wells Fargo Bank, N.A.
Interest Rate Derivatives Outstanding
Notional	$ 200,000,000
Fixed Interest Rate in Contract	3.142%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 500,000,000
Fixed Interest Rate in Contract	2.249%
Interest Rate Swaps | Citibank, N.A.
Interest Rate Derivatives Outstanding
Notional	$ 200,000,000
Fixed Interest Rate in Contract	2.83%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 500,000,000
Fixed Interest Rate in Contract	2.439%
Interest Rate Swaps | HSBC Bank USA, National Association
Interest Rate Derivatives Outstanding
Notional	$ 550,000,000
Fixed Interest Rate in Contract	2.45%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 1,000,000,000
Fixed Interest Rate in Contract	2.213%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 1,000,000,000
Fixed Interest Rate in Contract	1.8665%
Interest Rate Swaps | The Royal Bank of Scotland Plc
Interest Rate Derivatives Outstanding
Notional	$ 500,000,000
Fixed Interest Rate in Contract	1.98375%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 600,000,000
Fixed Interest Rate in Contract	2.883%
Interest Rate Swaps | HSBC Bank USA, National Association
Interest Rate Derivatives Outstanding
Notional	$ 500,000,000
Fixed Interest Rate in Contract	2.201%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 450,000,000
Fixed Interest Rate in Contract	2.0999%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 450,000,000
Fixed Interest Rate in Contract	2.1456%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 100,000,000
Fixed Interest Rate in Contract	2.0375%
Interest Rate Swaps | LCH Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 220,000,000
Fixed Interest Rate in Contract	2.1225%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 250,000,000
Fixed Interest Rate in Contract	2.778%
Interest Rate Swaps | CME Central Clearing
Interest Rate Derivatives Outstanding
Notional	$ 250,000,000
Fixed Interest Rate in Contract	2.387%

Derivatives and Hedging Activ69

Derivatives and Hedging Activities - Schedule of Credit Derivatives (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Credit Derivatives
Notional amount	$ 9,750,352	$ 7,132,274
GSE CRT | Embedded Credit Derivative
Credit Derivatives
Fair value amount	45,400	17,095
Notional amount	553,493	569,966
Maximum potential amount of future undiscounted payments	$ 553,493	$ 569,966

Derivatives and Hedging Activ70

Derivatives and Hedging Activities - Fair Value of Derivative Financial Instruments Classification on Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value
Derivative assets, at fair value	$ 6,896	$ 3,186
Derivative liabilities, at fair value	22,445	134,228
Interest Rate Swaps
Derivatives, Fair Value
Derivative assets, at fair value	6,896	3,085
Derivative liabilities, at fair value	31,548	133,833
Currency Forward Contracts
Derivatives, Fair Value
Derivative assets, at fair value	0	101
Derivative liabilities, at fair value	$ 1,217	$ 395

Derivatives and Hedging Activ71

Derivatives and Hedging Activities - Effect of Derivative Financial Instruments on Statement of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net									$ 67,838	$ (57,943)	$ (44,272)
Unrealized gain (loss), net									27,393	99,932	9,597
Gain (loss) on derivative instruments, net	$ 64,251	$ 1,955	$ (53,513)	$ 5,462	$ 230,713	$ 35,378	$ (90,363)	$ (238,543)	18,155	(62,815)	(219,048)
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net									67,838	(57,943)	(44,272)
Contractual net interest expense									(77,076)	(104,804)	(184,373)
Unrealized gain (loss), net									27,393	99,932	9,597
Gain (loss) on derivative instruments, net									18,155	(62,815)	(219,048)
Not Designated as Hedging Instrument | Credit Derivatives
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net											(1,140)
Contractual net interest expense											25,545
Unrealized gain (loss), net											(4,623)
Gain (loss) on derivative instruments, net											19,782
Not Designated as Hedging Instrument | GSE CRT Embedded Derivatives
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net									0	(6,017)	(2,184)
Contractual net interest expense									23,343	24,343	24,822
Unrealized gain (loss), net									28,305	42,817	(4,227)
Gain (loss) on derivative instruments, net									51,648	61,143	18,411
Not Designated as Hedging Instrument | Credit Default Swap Contract
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net											1,044
Contractual net interest expense											723
Unrealized gain (loss), net											(396)
Gain (loss) on derivative instruments, net											1,371
Not Designated as Hedging Instrument | Interest Rate Swaps
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net									72,894	(69,090)	(31,881)
Contractual net interest expense									(77,076)	(104,804)	(184,373)
Unrealized gain (loss), net									28,316	100,503	(554)
Gain (loss) on derivative instruments, net									24,134	(73,391)	(216,808)
Not Designated as Hedging Instrument | Interest Rate Swaptions
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net										(1,485)	(10,328)
Contractual net interest expense										0	0
Unrealized gain (loss), net										1,485	8,521
Gain (loss) on derivative instruments, net										0	(1,807)
Not Designated as Hedging Instrument | TBAs
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net											(2,292)
Contractual net interest expense											0
Unrealized gain (loss), net											558
Gain (loss) on derivative instruments, net											(1,734)
Not Designated as Hedging Instrument | Futures Contracts
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net											(943)
Contractual net interest expense											0
Unrealized gain (loss), net											(90)
Gain (loss) on derivative instruments, net											(1,033)
Not Designated as Hedging Instrument | Currency Forward Contracts
Derivative Instruments, Gain (Loss)
Realized gain (loss) on derivative instruments, net									(5,056)	12,632	1,172
Contractual net interest expense									0	0	0
Unrealized gain (loss), net									(923)	(2,056)	1,162
Gain (loss) on derivative instruments, net									$ (5,979)	$ 10,576	$ 2,334

Offsetting Assets and Liabili72

Offsetting Assets and Liabilities - Offsetting of Derivative Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives
Gross Amounts of Recognized Assets	$ 6,896	$ 3,186
Gross Amounts Offset in the Consolidated Balance Sheets	0	0
Net Amounts of Assets presented in the Consolidated Balance Sheets	6,896	3,186
Gross Amounts Not Offset in the Consolidated Balance Sheets, Financial Instruments	0	(1,640)
Gross Amounts Not Offset in the Consolidated Balance Sheets, Collateral Received	(6,896)	(1,546)
Net amount	$ 0	$ 0

Offsetting Assets and Liabili73

Offsetting Assets and Liabilities - Offsetting of Derivative Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives:
Gross amounts of recognized liabilities, derivatives	$ 22,445	$ 134,228
Gross amounts offset in the consolidated balance sheet, derivatives	0	0
Net amounts of liabilities presented in the consolidated balance sheet, derivatives	22,445	134,228
Financial instruments, derivatives	(21,169)	(45,738)
Collateral received, derivatives	(620)	(85,787)
Net amount, derivatives	656	2,703
Repurchase Agreements:
Gross amounts of recognized liabilities, repurchase agreements	14,080,801	11,160,669
Gross amounts offset in the consolidated balance sheet, repurchase agreements	0	0
Net amounts of assets presented in the consolidated balance sheet, repurchase agreements	14,080,801	11,160,669
Financial instruments, repurchase agreements	(14,080,801)	(11,160,669)
Collateral received, repurchase agreements	0	0
Net amount, repurchase agreements	0	0
Secured Loans:
Gross amounts of recognized liabilities, secured loans	1,650,000	1,650,000
Gross amounts offset in the consolidated balance sheet, secured loans	0	0
Net amounts of assets presented in the consolidated balance sheet, secured loans	1,650,000	1,650,000
Financial instruments, secured loans	(1,650,000)	(1,650,000)
Collateral received, secured loans	0	0
Net amount, secured loans	0	0
Total gross amount of recognized liabilities	15,753,246	12,944,897
Total gross amounts offset in the consolidated balance sheets	0	0
Net amounts of assets presented in the consolidated balance sheets	15,753,246	12,944,897
Total financial instruments	(15,751,970)	(12,856,407)
Total collateral received	(620)	(85,787)
Total net amount	656	2,703
Cash collateral received	7,327	1,700
Due from counterparties	620	86,450
Securities sold under agreements to repurchase fair value of collateral	15,523,415	12,444,304
Collateral pledged against secured loans	1,900,000	1,900,000
Interest Rate Swaps
Derivatives:
Gross amounts of recognized liabilities, derivatives	31,548	133,833
Secured Loans:
Fair value of securities pledged against derivatives	24,325	132,762
Due from counterparties	600	$ 86,500
Central Clearing Counterparty
Derivatives:
Gross amounts of recognized liabilities, derivatives	$ 10,300

Fair Value of Financial Instr74

Fair Value of Financial Instruments - Fair Values Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed and credit risk transfer securities	$ 18,190,754	$ 14,981,331
Derivative assets, at fair value	6,896	3,186
Derivative liabilities, at fair value	22,445	134,228
Investments in unconsolidated ventures	$ 25,972	$ 33,301
Weighted average remaining term of investments in unconsolidated ventures	1 year 11 months	1 year 4 months
Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets, at fair value	$ 6,896	$ 3,186
Other assets, at fair value	29,951	33,801
NAV as a practical expedient	25,972	33,301
Total assets	18,227,601	15,018,318
Derivative liabilities, at fair value	32,765	134,228
Total liabilities	32,765	134,228
Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets, at fair value	0
Other assets, at fair value	3,979
Total assets	3,979	500
Derivative liabilities, at fair value	0	0
Total liabilities	0	0
Recurring | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets, at fair value	6,896	3,186
Other assets, at fair value	0	0
Total assets	18,152,250	14,967,422
Derivative liabilities, at fair value	32,765	134,228
Total liabilities	32,765	134,228
Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets, at fair value	0
Other assets, at fair value	0	0
Total assets	45,400	17,095
Derivative liabilities, at fair value	0	0
Total liabilities	0	0
Mortgage-Backed and Credit Risk Transfer Securities, at Fair Value | Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Embedded derivatives at fair value	45,400	17,100
Embedded derivative asset	46,500	21,000
Embedded derivative liability	1,100	3,900
Mortgage-backed and GSE CRT securities | Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed and credit risk transfer securities	18,190,754	14,981,331
Mortgage-backed and GSE CRT securities | Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed and credit risk transfer securities	0	0
Mortgage-backed and GSE CRT securities | Recurring | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed and credit risk transfer securities	18,145,354	14,964,236
Mortgage-backed and GSE CRT securities | Recurring | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage-backed and credit risk transfer securities	45,400	17,095
Exchange-traded funds | Recurring | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in exchange-traded fund, at fair value	$ 4,000	$ 500

Fair Value of Financial Instr75

Fair Value of Financial Instruments - Net Derivative Asset (Liability) Level 3 Roll Forward (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total net gains / (losses) included in net income:
Unrealized gains on credit derivatives, net	$ 28,305	$ 42,817	$ (4,623)
Reverse of net unrealized gains on securities sold during period		(6,600)
Embedded Credit Derivative | GSE CRT
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	17,095	(25,722)
Sales and settlements		6,017
Total net gains / (losses) included in net income:
Realized gains/(losses), net	0	(6,017)
Unrealized gains/(losses), net	28,305	42,817
Ending balance	45,400	17,095	$ (25,722)
Unrealized gains on credit derivatives, net	$ 28,300	$ 36,200

Fair Value of Financial Instr76

Fair Value of Financial Instruments - Quantitative Information About Level 3 Fair Value Measurements (Detail) - Embedded Credit Derivative - GSE CRT - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation
Embedded derivatives	$ 45,400	$ 17,095	$ (25,722)
Level 3
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation
Embedded derivatives	$ 45,400	$ 17,095
Level 3 | Market Comparables, Vendor Pricing | Minimum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation
Weighted average life	2 years 7 months	2 years 6 months
Level 3 | Market Comparables, Vendor Pricing | Maximum
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation
Weighted average life	6 years 9 months	7 years 8 months
Level 3 | Market Comparables, Vendor Pricing | Weighted Average
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation
Weighted average life	4 years 9 months 30 days	5 years 3 months 24 days

Fair Value of Financial Instr77

Fair Value of Financial Instruments - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Carrying Value
Financial Instruments
Other assets	$ 74,250	$ 74,250
Total	266,058	347,605
Repurchase agreements	14,080,801	11,160,669
Secured loans	1,650,000	1,650,000
Exchangeable senior notes	143,231	397,041
Total	15,874,032	13,207,710
Estimated Fair Value
Financial Instruments
Other assets	74,250	74,250
Total	266,180	349,569
Repurchase agreements	14,080,460	11,161,034
Secured loans	1,650,000	1,650,000
Exchangeable senior notes	143,948	400,000
Total	15,874,408	13,211,034
Commercial loans, held-for-investment | Carrying Value
Financial Instruments
Mortgage loans, held-for-investment	191,808	273,355
Commercial loans, held-for-investment | Estimated Fair Value
Financial Instruments
Mortgage loans, held-for-investment	$ 191,930	$ 275,319

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction
Expenses from transactions with related party	$ 37,556	$ 34,541	$ 38,632
Investment in money market or mutual funds managed by affiliates of a related party	$ 88,381	161,788	53,199	$ 164,144
Management
Related Party Transaction
Fee paid by Company to Manager as percentage of Company's shareholders' equity	1.50%
Termination fee multiplier	3
Termination fees assessment period	24 months
Invesco Advisers, Inc. | Affiliated Entity
Related Party Transaction
Expenses from transactions with related party	$ 801	695	544
Investment in money market or mutual funds managed by affiliates of a related party	$ 74,400	149,900
Loans origination and commitment fees paid		690	$ 1,300
Accounting for Premiums and Discounts Associated with Non-Agency RMBS | Management
Related Party Transaction
Cumulative one-time adjustment		$ 2,300

Related Party Transactions - Sc

Related Party Transactions - Schedule of Related Party Transactions (Details) - Management - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction
Amounts of transaction with related party	$ 6,296	$ 7,036	$ 6,485
Incurred costs, prepaid or expensed
Related Party Transaction
Amounts of transaction with related party	5,997	6,986	6,463
Incurred costs, charged against equity as a cost of raising capital
Related Party Transaction
Amounts of transaction with related party	299	0	22
Incurred costs, capitalized to other assets
Related Party Transaction
Amounts of transaction with related party	$ 0	$ 50	$ 0

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Sep. 14, 2017	Dec. 31, 2017	Aug. 31, 2017	Sep. 27, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 28, 2017
Class of Stock
Proceeds from issuance of common stock													$ 0	$ 35	$ 191
Repurchase of shares of common stock														$ 25,000	$ 125,595
Decrease of net income attributable to common stockholders													$ 373
Common Stock
Class of Stock
Equity distribution agreement, number of shares to sell		17,000,000
Repurchase of shares of common stock (in shares)														2,063,451
Average price per repurchased common share														$ 12.12
Repurchase of shares of common stock														$ 25,000
Number of shares authorized to be repurchased (in shares)		18,239,082			18,239,082								18,239,082
Series C Cumulative Redeemable Preferred Stock
Class of Stock
Dividends declared, preferred stock (usd per share)	$ 0.68229												$ 0.68229
Preferred stock, liquidation preference			$ 25
Preferred stock, price per share per annum				$ 1.875
Preferred stock dividend rate			7.50%
Number of shares in public offering			11,500,000
Proceeds from issuance of redeemable preferred stock			$ 287,500
Payments of stock issuance costs			$ 9,400
Series C Cumulative Redeemable Preferred Stock | LIBOR
Class of Stock
Preferred stock dividends basis spread on variable rate																5.289%
Series A Cumulative Redeemable Preferred Stock
Class of Stock
Dividends declared, preferred stock (usd per share)					$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 1.9376	$ 1.9376
Preferred stock, percentage rate		7.75%			7.75%								7.75%
Preferred stock, liquidation preference		$ 25			$ 25								$ 25
Preferred stock, price per share per annum													1.9375
Series B Cumulative Redeemable Preferred Stock
Class of Stock
Dividends declared, preferred stock (usd per share)						$ 0.4844	$ 0.4844	$ 0.4844	0.4844	$ 0.4844	$ 0.4844	$ 0.4844	1.9376	$ 1.9376
Preferred stock, price per share per annum													$ 1.9375
Preferred stock dividend rate													7.75%
Preferred stock redemption price (in usd per share)		$ 25			$ 25								$ 25
Series B Cumulative Redeemable Preferred Stock | LIBOR
Class of Stock
Preferred stock dividends basis spread on variable rate		5.18%			5.18%								5.18%
Preferred Stock
Class of Stock
Preferred stock, liquidation preference		$ 25			$ 25								$ 25
Preferred stock redemption price (in usd per share)		$ 25			$ 25								$ 25
DRSPP | Common Stock
Class of Stock
Common stock, shares issued (in shares)														3,201	12,945
Price of shares issued (in dollars per share)									$ 11.08					$ 11.08	$ 14.75
Proceeds from issuance of common stock														$ 35	$ 191
2009 Equity Incentive Plan
Class of Stock
Total unrecognized compensation cost expected to be recognized		$ 239			$ 239								$ 239
Total unrecognized compensation cost expected to be recognized, period for recognition													39 months
Total unrecognized compensation cost expected to be recognized, weighted average remaining vesting period													15 months
2009 Equity Incentive Plan | Non-Executive Director
Class of Stock
Compensation expense recognized													$ 453	$ 340	$ 340
Restricted stock awards during period (in shares)													25,006	25,068	23,776
2009 Equity Incentive Plan | Employees of the Manager and its Affiliates
Class of Stock
Compensation expense recognized													$ 138	$ 100	$ 219
2009 Equity Incentive Plan | Common Stock
Class of Stock
Common stock options reserved for issuance		1,000,000			1,000,000								1,000,000
Number of common stock remain available for future issuance (in shares)		792,520			792,520								792,520

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Nonvested Restricted Stock Units (Details) - Restricted Stock Units (RSUs)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Restricted Stock Units
Balance at beginning of the period (in shares) | shares	18,807
Shares granted during the year (in shares) | shares	8,115
Shares vested during the year (in shares) | shares	(7,095)
Balance at end of the period (in shares) | shares	19,827
Weighted Average Grant Date Fair Value
Balance at beginning of the period (in usd per share) | $ / shares	$ 14.37
Shares granted during the year (in usd per share) | $ / shares	15.55
Shares vested during the year (in usd per share) | $ / shares	15.78
Balance at end of the period (in usd per share) | $ / shares	$ 14.35

Stockholders' Equity - Componen

Stockholders' Equity - Components of AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated other comprehensive income (loss) from derivative instruments:
Accumulated other comprehensive income	$ 261,029	$ 293,668
Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net	(9,885)	(37,632)	$ (191,053)
Reclassification of unrealized (gain) loss on sale of MBS and GSE CRT to gain (loss) on investments, net	1,508	6,134	(7,484)
Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense	(25,544)	5,154	66,757
Currency translation adjustments on investment in unconsolidated venture	863	128	(32)
Total other comprehensive income (loss)	(33,058)	(26,216)	(131,812)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	2,270,184	2,266,908	2,638,850
Other comprehensive income/(loss), net	(33,058)	(26,216)	(131,812)
Other comprehensive income/(loss) attributable to non-controlling interest	418	348
Rebalancing of ownership percentage of non-controlling interest	1	912
Ending balance	2,656,878	2,270,184	2,266,908
Equity method investments, including portion attributable to noncontrolling interest
Accumulated other comprehensive income (loss) from derivative instruments:
Currency translation adjustments on investment in unconsolidated venture	863	128
Total other comprehensive income (loss)	863	128
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Other comprehensive income/(loss), net	863	128
Other comprehensive income/(loss) attributable to non-controlling interest	(11)	(1)
Available-for-sale securities, including portion attributable to noncontrolling interest
Accumulated other comprehensive income (loss) from derivative instruments:
Unrealized gain (loss) on mortgage-backed and credit risk transfer securities, net	(9,885)	(37,632)
Reclassification of unrealized (gain) loss on sale of MBS and GSE CRT to gain (loss) on investments, net	1,508	6,134
Total other comprehensive income (loss)	(8,377)	(31,498)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Other comprehensive income/(loss), net	(8,377)	(31,498)
Other comprehensive income/(loss) attributable to non-controlling interest	106	412
Rebalancing of ownership percentage of non-controlling interest	1	5,161
Derivatives and hedging, including portion attributable to noncontrolling interest
Accumulated other comprehensive income (loss) from derivative instruments:
Accumulated other comprehensive income	123,900	149,100
Reclassification of amortization of net deferred (gain) loss on de-designated interest rate swaps to repurchase agreements interest expense	(25,544)	5,154
Total other comprehensive income (loss)	(25,544)	5,154
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Other comprehensive income/(loss), net	(25,544)	5,154
Other comprehensive income/(loss) attributable to non-controlling interest	323	(63)
Rebalancing of ownership percentage of non-controlling interest	0	(4,249)
Equity method investment attributable to parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	95	(32)
Ending balance	947	95	(32)
Available-for-sale securities attributable to parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	144,458	170,383
Ending balance	136,188	144,458	170,383
Derivatives and hedging attributable to parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	149,115	148,273
Ending balance	123,894	149,115	148,273
AOCI attributable to parent
Accumulated other comprehensive income (loss) from derivative instruments:
Total other comprehensive income (loss)	(32,640)	(25,868)	(130,223)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	293,668	318,624	448,847
Other comprehensive income/(loss), net	(32,640)	(25,868)	(130,223)
Rebalancing of ownership percentage of non-controlling interest	1	912
Ending balance	$ 261,029	$ 293,668	$ 318,624

Stockholders' Equity - Common D

Stockholders' Equity - Common Dividends Declared Per Share (Detail) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Common Stock
Dividends Per Share
Dividends declared, common stock (usd per share)	$ 0.42	$ 0.41	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 1.63	$ 1.6

Stockholders' Equity - Preferre

Stockholders' Equity - Preferred Stock Dividends Declared Per Share (Detail) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Series A Cumulative Redeemable Preferred Stock
Dividends Per Share
Dividends declared, preferred stock (usd per share)	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 1.9376	$ 1.9376
Series B Cumulative Redeemable Preferred Stock
Dividends Per Share
Dividends declared, preferred stock (usd per share)		$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 1.9376	$ 1.9376

Stockholders' Equity - Dividend

Stockholders' Equity - Dividends Declared Per Share and Related Tax Characterizations (Details) - $ / shares	Sep. 14, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Series A Cumulative Redeemable Preferred Stock
Dividends Per Share
Dividends declared, preferred stock (usd per share)		$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 0.4844	$ 1.9376	$ 1.9376
Series A Cumulative Redeemable Preferred Stock | Ordinary Dividends
Dividends Per Share
Dividends declared, preferred stock (usd per share)										1.9376	1.9376
Series A Cumulative Redeemable Preferred Stock | Capital Gain Distribution
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0	0
Series A Cumulative Redeemable Preferred Stock | Carry Forward
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0	0
Series B Cumulative Redeemable Preferred Stock
Dividends Per Share
Dividends declared, preferred stock (usd per share)			0.4844	0.4844	0.4844	0.4844	0.4844	0.4844	0.4844	1.9376	1.9376
Series B Cumulative Redeemable Preferred Stock | Ordinary Dividends
Dividends Per Share
Dividends declared, preferred stock (usd per share)										1.9376	1.9376
Series B Cumulative Redeemable Preferred Stock | Capital Gain Distribution
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0	0
Series B Cumulative Redeemable Preferred Stock | Carry Forward
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0	0
Series C Cumulative Redeemable Preferred Stock
Dividends Per Share
Dividends declared, preferred stock (usd per share)	$ 0.68229									0.68229
Series C Cumulative Redeemable Preferred Stock | Ordinary Dividends
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0.68229
Series C Cumulative Redeemable Preferred Stock | Capital Gain Distribution
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0
Series C Cumulative Redeemable Preferred Stock | Carry Forward
Dividends Per Share
Dividends declared, preferred stock (usd per share)										0
Common Stock
Dividends Per Share
Dividends declared, common stock (usd per share)		$ 0.42	$ 0.41	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.40	$ 0.40	1.63	1.6
Spillover dividend (usd per share)												$ 0.257840
Common Stock | Ordinary Dividends
Dividends Per Share
Dividends declared, common stock (usd per share)										1.48004	1.85784
Common Stock | Capital Gain Distribution
Dividends Per Share
Dividends declared, common stock (usd per share)										0	0
Common Stock | Carry Forward
Dividends Per Share
Dividends declared, common stock (usd per share)										$ 0.14996	$ 0

Earnings per Common Share (Deta

Earnings per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Basic Earnings:
Net income (loss) available to common stockholders	$ 137,436	$ 49,127	$ 46,834	$ 87,130	$ 270,105	$ 129,219	$ (11,617)	$ (156,160)	$ 320,527	$ 231,547	$ 89,847
Effect of dilutive securities:
Income allocated to exchangeable senior notes									13,340	22,467	0
Income (loss) allocated to non-controlling interest									4,450	3,287	1,344
Dilutive net income (loss) available to stockholders									$ 338,317	$ 257,301	$ 91,191
Basic Earnings:
Shares available to common stockholders (in shares)									111,610,393	111,973,404	121,377,585
Effect of dilutive securities:
Restricted stock awards (in shares)									20,000	20,000	41,000
Non-controlling interest OP Units (in shares)									1,425,000	1,425,000	1,425,000
Exchangeable senior notes (in shares)									9,986,000	16,836,000	0
Dilutive Shares (in shares)									123,040,827	130,254,003	122,843,838
Earnings (loss) per share:
Basic (in usd per share)	$ 1.23	$ 0.44	$ 0.42	$ 0.78	$ 2.42	$ 1.16	$ (0.10)	$ (1.38)	$ 2.87	$ 2.07	$ 0.74
Diluted (in usd per share)	$ 1.18	$ 0.43	$ 0.41	$ 0.73	$ 2.15	$ 1.05	$ (0.10)	$ (1.38)	$ 2.75	$ 1.98	$ 0.74
Exchangeable Senior Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share
Potential common shares excluded from diluted earnings per common share											16,835,720

Non-controlling Interest - Op87

Non-controlling Interest - Operating Partnership (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Noncontrolling Interest
Non-controlling interest related to the outstanding of OP units		1,425,000
Rebalancing of ownership percentage of non-controlling interest		$ 1,000	$ 912,000
Non-controlling interest
Noncontrolling Interest
Non-controlling interest in operating partnership		1.30%
Rebalancing of ownership percentage of non-controlling interest	$ (3,600,000)	$ (3,953,000)	2,086,000
Net income (loss) allocated		4,450,000	3,287,000	$ 1,344,000
Distributions paid		2,294,000	2,280,000	$ 2,494,000
Distributions payable to non-controlling interest		598,500	570,000
Accumulated Other Comprehensive Income (loss)
Noncontrolling Interest
Rebalancing of ownership percentage of non-controlling interest		1,000	912,000
Additional Paid in Capital
Noncontrolling Interest
Rebalancing of ownership percentage of non-controlling interest	$ 3,600,000	$ 3,952,000	$ (2,998,000)

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Undrawn capital and purchase commitments for unconsolidated ventures sponsored by an affiliate	$ 10.2	$ 15.5
Unfunded commitment	$ 4.8	$ 9.7

Summarized Quarterly Results 89

Summarized Quarterly Results of Operations (Unaudited) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest Income
Mortgage-backed and credit risk transfer securities	$ 147,509	$ 134,138	$ 121,027	$ 118,873	$ 108,871	$ 112,467	$ 112,860	$ 122,246	$ 521,547	$ 456,444	$ 523,893
Commercial loans	5,472	6,251	6,021	5,764	5,718	5,680	5,947	4,893	23,508	22,238	15,331
Total interest income	152,981	140,389	127,048	124,637	114,589	118,147	118,807	127,139	545,055	478,682	650,132
Interest Expense
Repurchase agreements	51,955	45,907	36,072	29,947	26,048	24,892	31,260	41,800	163,881	124,000	166,892
Secured loans	5,878	5,544	4,535	3,413	2,738	2,746	2,688	2,715	19,370	10,887	6,579
Exchangeable senior notes	2,104	2,724	3,504	5,008	5,620	5,620	5,614	5,613	13,340	22,467	22,461
Total interest expense	59,937	54,175	44,111	38,368	34,406	33,258	39,562	50,128	196,591	157,354	277,973
Net interest income	93,044	86,214	82,937	86,269	80,183	84,889	79,245	77,011	348,464	321,328	372,159
Other income (loss)
Gain (loss) on investments, net	(17,153)	(11,873)	11,175	(1,853)	(23,402)	(7,155)	1,414	11,601	(19,704)	(17,542)	(18,005)
Equity in earnings (losses) of unconsolidated ventures	(47)	408	(154)	(1,534)	400	729	202	1,061	(1,327)	2,392	12,630
Gain (loss) on derivative instruments, net	64,251	1,955	(53,513)	5,462	230,713	35,378	(90,363)	(238,543)	18,155	(62,815)	(219,048)
Realized and unrealized credit derivative income (loss), net	13,220	(2,930)	21,403	19,955	3,579	31,926	17,228	8,410	51,648	61,143	19,782
Net loss on extinguishment of debt	(233)	(1,344)	(526)	(4,711)	0	0	0	0	(6,814)	0	0
Other investment income (loss), net	1,206	2,313	2,533	1,329	(1,385)	(554)	(2,745)	(318)	7,381	(5,002)	944
Total other income (loss)	61,244	(11,471)	(19,082)	18,648	209,905	60,324	(74,264)	(217,789)	49,339	(21,824)	(203,697)
Expenses	11,972	11,254	10,635	10,885	10,745	8,555	10,957	11,549	44,746	41,806	54,620
Net income	142,316	63,489	53,220	94,032	279,343	136,658	(5,976)	(152,327)	353,057	257,698	114,055
Net income attributable to non-controlling interest	1,794	800	670	1,186	3,522	1,723	(75)	(1,883)	4,450	3,287	1,344
Net income attributable to Invesco Mortgage Capital Inc.	140,522	62,689	52,550	92,846	275,821	134,935	(5,901)	(150,444)	348,607	254,411	112,711
Dividends to preferred stockholders	3,086	13,562	5,716	5,716	5,716	5,716	5,716	5,716	28,080	22,864	22,864
Net income attributable to common stockholders	$ 137,436	$ 49,127	$ 46,834	$ 87,130	$ 270,105	$ 129,219	$ (11,617)	$ (156,160)	$ 320,527	$ 231,547	$ 89,847
Net income (loss) attributable to common stockholders
Basic (in usd per share)	$ 1.23	$ 0.44	$ 0.42	$ 0.78	$ 2.42	$ 1.16	$ (0.10)	$ (1.38)	$ 2.87	$ 2.07	$ 0.74
Diluted (in usd per share)	$ 1.18	$ 0.43	$ 0.41	$ 0.73	$ 2.15	$ 1.05	$ (0.10)	$ (1.38)	$ 2.75	$ 1.98	$ 0.74

Schedule IV Mortgage Loans on90

Schedule IV Mortgage Loans on Real Estate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Carrying Value of Mortgage Loans on Real Estate:
Beginning balance	$ 273,355	$ 209,062	$ 3,510,759
Additions:
Originations and purchases of new loans	4,799	87,474	530,399
Premium (discount) on new loans	0	(272)	(131)
Amortization of commercial loan origination fees and premium (discount)	337	302	(6,204)
Deductions:
Collection of principal	90,713	15,000	642,361
Reduction in provision for loan losses	0		(213)
Loss on foreign currency revaluation	(4,030)	8,211	1,951
Deconsolidation of VIEs	0	0	3,181,662
Ending balance	191,808	$ 273,355	$ 209,062
Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	191,894
Carrying Amount of Mortgages	191,808
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
FL | Hotel | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	21,000
Carrying Amount of Mortgages	20,990
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
FL | Hotel | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	7.23%
FL | Retail/Mixed Use | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	$ 28,000
Carrying Amount of Mortgages	28,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
FL | Retail/Mixed Use | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	7.25%
FL | Multifamily | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	$ 10,000
Carrying Amount of Mortgages	9,994
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
FL | Multifamily | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	7.50%
AZ | Office | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	$ 33,647
Carrying Amount of Mortgages	33,628
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
AZ | Office | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	6.96%
International | Hotel | Mezzanine Loan
Mortgage Loans on Real Estate
Percentage over base rate	7.50%
Face Amount of Mortgages	$ 46,668
Carrying Amount of Mortgages	46,621
Principal Amount of Loans Subject to Delinquent Principal or Interest	0
TX | Hotel | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	25,000
Carrying Amount of Mortgages	25,000
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
TX | Hotel | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	8.50%
TX | Multifamily | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	$ 7,000
Carrying Amount of Mortgages	6,996
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
TX | Multifamily | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	7.50%
CA | Office | Mezzanine Loan
Mortgage Loans on Real Estate
Face Amount of Mortgages	$ 20,579
Carrying Amount of Mortgages	20,579
Principal Amount of Loans Subject to Delinquent Principal or Interest	$ 0
CA | Office | Mezzanine Loan | LIBOR
Mortgage Loans on Real Estate
Percentage over base rate	7.65%