Summary of Significant Accounting Policies - Allowance for Credit Losses - Securities (Details) $ in Millions	Dec. 31, 2021 USD ($)
Accounting Policies [Abstract]
Accrued interest on held to maturity debt securities	$ 3.7
ACL for securities HTM	0.0
Accrued interest on available for sale debt securities	5.0
ACL on AFS portfolio	$ 0.0

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Amount, after allowance for credit loss, of accrued interest 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
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Amount excluding accrued interest, of allowance for credit 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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Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at amortized cost (held-to-maturity).

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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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