Financial Derivatives Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
U.S. Treasury securities sold short, at fair value	$ 9,974	$ 0
US Treasury Securities [Member]
Derivative [Line Items]
U.S. Treasury securities sold short, at fair value	10,000
Investment Sold, Not yet Purchased, Balance, Principal Amount	$ 10,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Fair value of obligations arising from US treasury and other US government and agency debt obligations sold short.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42429-110968

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- Definition

For investments which are quantified by principal amount, the principle balance held at close of period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-12A.Column B)
-URI http://asc.fasb.org/extlink&oid=122147990&loc=d3e611177-123010

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