Loans and Allowance for Credit Losses on Loans - Troubled Debt and Modifications (Details) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2022 USD ($) loan item	Jun. 30, 2021 loan item	Jun. 30, 2022 USD ($) loan item	Jun. 30, 2021 item loan	Dec. 31, 2021 USD ($) loan
Troubled debt and modifications
Number of troubled debt restructuring	0	0	0	0
Number of loans restructured defaulted \| item	0	0	0	0
Number of loans modified in accordance with CARES Act	1		1		1
Amount of outstanding loans modified in accordance with CARES Act \| $	$ 36.8		$ 36.8		$ 36.8
Residential real estate
Troubled debt and modifications
Number of loans in the process of foreclosure			0		0

The number of loans modified in accordance with the CARES Act.

No definition available.

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- Definition

The amount of outstanding loans that were modified in accordance with the CARES Act and therefore not classified as delinquent.

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that are in the process of foreclosure.

+ References

No definition available.

+ Details

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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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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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