Investments (Investments Pledged as Collateral) (Details) $ in Millions	Sep. 30, 2021 USD ($)
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral On Deposit With Various State And Regulatory Agencies	$ 26.1
Securities Pledged As Collateral	159.9
Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	74.4
Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities Pledged as Collateral on FHLB	59.4
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	22.1
Securities Pledged As Collateral	22.1
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	4.0
Securities Pledged As Collateral	4.0
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
Securities Pledged As Collateral	112.6
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	67.8
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	44.8
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
Securities Pledged As Collateral	21.2
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	6.6
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	$ 14.6

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

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

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- 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 http://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 http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- 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.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

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