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Derivative Instruments - Summary of net realized gains (losses) recorded in the consolidated statements of income (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Net realized gains (losses) on derivative instruments |  |  |  |  |
Net realized gains (losses) on derivative instruments | [1] | $ 20,369 | $ 42,893 | $ 146,722 | $ 142,730
Not designated as hedging instrument |  |  |  |  |
Net realized gains (losses) on derivative instruments |  |  |  |  |
Net realized gains (losses) on derivative instruments |  | 20,369 | 42,893 | 146,722 | 142,730
Futures contracts | Not designated as hedging instrument |  |  |  |  |
Net realized gains (losses) on derivative instruments |  |  |  |  |
Net realized gains (losses) on derivative instruments |  | 10,945 | 46,194 | 105,282 | 140,503
Foreign currency forward contracts | Not designated as hedging instrument |  |  |  |  |
Net realized gains (losses) on derivative instruments |  |  |  |  |
Net realized gains (losses) on derivative instruments |  | 10,813 | 2,044 | 3,466 | (17,030)
TBAs | Not designated as hedging instrument |  |  |  |  |
Net realized gains (losses) on derivative instruments |  |  |  |  |
Net realized gains (losses) on derivative instruments |  | 120 | 269 | 1,129 | 507
Other | Not designated as hedging instrument |  |  |  |  |
Net realized gains (losses) on derivative instruments |  |  |  |  |
Net realized gains (losses) on derivative instruments |  | $ (1,509) | $ (5,614) | $ 36,845 | $ 18,750
[1] | See note 9 for information on the Company’s derivative instruments.

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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