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Other Assets - TBA Securities (Details)	12 Months Ended
	Dec. 31, 2021 USD ($)
Derivative [Line Items]
Notional Amount	$ 900,000,000
TBA Securities | Short
Derivative [Line Items]
Aggregate value	(1,300,000)
Gain on derivative	2,000,000
FNCL 2.5 1/22 | Short
Derivative [Line Items]
Notional Amount	180,000,000
FNCL 2 1/21 | Short
Derivative [Line Items]
Notional Amount	$ 130,000,000

X

- Definition

Amount of increase in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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- Definition

Aggregate net fair value of all derivative instruments designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

+ References

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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=125515794&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=125515794&loc=SL5579245-113959

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