Note 8 - Property Held for Sale - Activity for Property Held for Sale (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Beginning balance	$ 5,067	$ 9,858	$ 15,588
Acquisitions	217	6	532
Capitalized improvements	2	36	0
Dispositions	(1,425)	(4,646)	(4,845)
Valuation adjustments	(132)	(187)	(1,417)
Balance at year end	$ 3,729	$ 5,067	$ 9,858

Amount of dispositions of property held for sale.

No definition available.

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- Definition

Amount of valuation adjustments on other real estate and foreclosed assets.

+ References

No definition available.

+ Details

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- Definition

Amount of capitalized improvements on property held for sale acquired through foreclosure.

+ References

No definition available.

+ Details

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Namespace Prefix:	smmf_
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- Definition

Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

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Balance Type:	debit
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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481990/310-10-45-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-11

+ Details

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