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Derivative Instruments Schedule of Futures (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019
Derivative [Line Items] |  |
Derivative, Fair Value, Net | $ (18,502) | $ 2,133
Futures [Member] | Short [Member] |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | (80,200) | (33,400)
US Treasury Note Futures [Member] | Futures [Member] |  |
Derivative [Line Items] |  |
Derivative, Fair Value, Net | $ (3,369) | $ 338
Derivative, Average Remaining Maturity | 2 months 21 days | 2 months 22 days
US Treasury Note Futures [Member] | Futures [Member] | Long [Member] |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ (2,200) | $ (4,100)
Derivative, Fair Value, Net | $ 331 | $ (96)
Derivative, Average Remaining Maturity | 2 months 26 days | 2 months 26 days
US Treasury Note Futures [Member] | Futures [Member] | Short [Member] |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ (82,400) | $ (37,500)
Derivative, Fair Value, Net | $ (3,700) | $ 434
Derivative, Average Remaining Maturity | 2 months 26 days | 2 months 22 days

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- Definition Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: 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=118260190&loc=d3e13433-108611 + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 + Details
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