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

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

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 https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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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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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.

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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 https://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 https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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