Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563

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- Definition

Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Subsequent Event (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
Subsequent Event (Details) - USD ($) $ in Millions	Jan. 31, 2023	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Subsequent Event [Line Items]
Available for sale		$ 26,699.9	$ 26,699.9	$ 38,010.5
Debt securities, available-for-sale, realized loss		(213.0)	214.0	1.7	$ 3.8
Debt securities, available-for-sale, realized gain			0.0	$ 1.4	$ 3.4
Available For Sale, Debt Securities, Portfolio For Sale
Subsequent Event [Line Items]
Available for sale		$ 2,100.0	$ 2,100.0
Subsequent Event
Subsequent Event [Line Items]
Debt securities, available-for-sale, realized gain	$ 6.9