Short-Term Borrowings - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Federal Funds Purchased
Short-term borrowings
Outstanding credit facility	$ 0.0	$ 0.0
Unsecured maximum borrowing capacity	87.0	87.0
FHLB Short-term advances
Short-term borrowings
Outstanding credit facility	531.6	$ 677.4
Unsecured Line Of Credit With Bank of North Dakota
Short-term borrowings
Unused line of credit	$ 15.0

Amount of the fee for available but unused credit capacity under the credit facility.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

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+ References

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