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Derivative Instruments Schedule of Derivatves (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value | [1] | $ 23,049 | $ 8,792
Financial derivatives–liabilities, at fair value | [1] | (333) | (1,863)
Derivative, Fair Value, Net |  | 22,716 | 6,929
TBA securities- purchase contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Fair Value, Net | [2] | (262) | (240)
TBA securities- sale contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Fair Value, Net | [2] | 1,389 | (93)
Derivative Financial Instruments, Assets [Member] | TBA securities- purchase contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value | [2] | 33 | 26
Derivative Financial Instruments, Assets [Member] | TBA securities- sale contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value | [2] | 1,414 | 376
Derivative Financial Instruments, Assets [Member] | Futures [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value |  | 3,413 | 171
Derivative Financial Instruments, Liabilities [Member] | TBA securities- purchase contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–liabilities, at fair value | [2] | (295) | (266)
Derivative Financial Instruments, Liabilities [Member] | TBA securities- sale contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–liabilities, at fair value | [2] | (25) | (469)
Short [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Fair Value, Net |  | 18,176 | 6,347
Short [Member] | Derivative Financial Instruments, Assets [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value |  | 18,189 | 7,475
Short [Member] | Derivative Financial Instruments, Liabilities [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–liabilities, at fair value |  | (13) | (1,128)
Long [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Fair Value, Net |  |  | 563
Long [Member] | Derivative Financial Instruments, Assets [Member] | Interest Rate Swap [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value |  | 0 | 563
Long [Member] | Derivative Financial Instruments, Assets [Member] | Swaption [Member] |  |  |
Derivative [Line Items] |  |  |
Financial derivatives–assets, at fair value |  | $ 0 | $ 181
[1] | In the Company's Consolidated Balance Sheet, all balances associated with the repurchase agreements and financial derivatives are presented on a gross basis.
[2] | Net carrying value represents the difference between the market value of the TBA contract as of period end and the cost basis and is reported in Financial derivatives-assets at fair value and Financial derivatives-liabilities at fair value on the Consolidated Balance Sheet.

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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