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Investments (Investments Pledged as Collateral) (Details) $ in Millions	Mar. 31, 2023 USD ($)
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral On Deposit With Various State And Regulatory Agencies	$ 23.4
Security Owned and Pledged as Collateral, Fair Value	127.1
Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	65.7
Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	38.0
U.S. Government and Government Agencies [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral On Deposit With Various State And Regulatory Agencies	19.9
Security Owned and Pledged as Collateral, Fair Value	19.9
U.S. Government and Government Agencies [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	0.0
U.S. Government and Government Agencies [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	0.0
Obligations of States and Political Subdivisions [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral On Deposit With Various State And Regulatory Agencies	3.5
Security Owned and Pledged as Collateral, Fair Value	3.5
Obligations of States and Political Subdivisions [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	0.0
Obligations of States and Political Subdivisions [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	0.0
Residential Mortgage Backed Securities [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral On Deposit With Various State And Regulatory Agencies	0.0
Security Owned and Pledged as Collateral, Fair Value	89.6
Residential Mortgage Backed Securities [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	61.2
Residential Mortgage Backed Securities [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	28.4
Commercial Mortgage Backed Securities [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral On Deposit With Various State And Regulatory Agencies	0.0
Security Owned and Pledged as Collateral, Fair Value	14.1
Commercial Mortgage Backed Securities [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	4.5
Commercial Mortgage Backed Securities [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	$ 9.6

X

- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

+ References

No definition available.

+ Details

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Balance Type:	debit
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X

- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 825
-Section 50
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=123600598&loc=SL75763979-209797

+ Details

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Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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X

- 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

No definition available.

+ Details

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- Details

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X

- Details

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- Details

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