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DERIVATIVE INSTRUMENTS - Summary of Swaptions Outstanding (Details) - Notional - Long Positions - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Long pay
Derivative [Line Items]
Current Underlying Notional	$ 1,250,000	$ 1,250,000
Weighted Average Underlying Fixed Rate	2.21%	2.21%
Weighted Average Underlying Years to Maturity	7 years 5 months 8 days	7 years 8 months 8 days
Weighted Average Months to Expiration	5 months 6 days	8 months 5 days
Long receive
Derivative [Line Items]
Current Underlying Notional	$ 500,000	$ 500,000
Weighted Average Underlying Fixed Rate	1.65%	1.65%
Weighted Average Underlying Years to Maturity	10 years 18 days	10 years 3 months 18 days
Weighted Average Months to Expiration	15 days	3 months 15 days

X

- Definition

Derivative Portfolio Expiration Period

+ References

No definition available.

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X

- Definition

Interest rate swaptions weighted average underlying pay rate.

+ References

No definition available.

+ Details

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X

- 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.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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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
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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