Number of Unrelated Parties

No definition available.

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- Definition

Subordinated borrowing, not pre-payable within number of years.

+ References

No definition available.

+ Details

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- Definition

Subordinated borrowing, term

+ References

No definition available.

+ Details

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- Definition

Subordinated debt amount qualifying as tier two capital reduced by percent each year until maturity.

+ References

No definition available.

+ Details

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- Definition

Subordinated Debt, Number of Issuances

+ References

No definition available.

+ Details

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- Definition

Subordinated debt qualifies as tier two capital under federal reserve board guidelines, debt maturity

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Details

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- Definition

The cash outflow from the repayment of long-term borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in case of liquidation of the entity's assets before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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- Definition

Stated interest rate of the subordinated debt.

+ References

No definition available.

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 10

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Article 5

-Subsection 19, 20, 22

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Borrowed Funds Borrowed Funds (Subordinated Debentures) (Narrative) (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2009 subordinated_debt party	Dec. 31, 2008	Jan. 31, 2015	Dec. 31, 2013
Debt Instrument [Line Items]
Subordinated debentures	$ 16,800,000us-gaap_SubordinatedDebt	$ 6,800,000us-gaap_SubordinatedDebt	$ 10,000,000us-gaap_SubordinatedDebt		$ 16,800,000us-gaap_SubordinatedDebt
Tier 2 capital	5 years
Tier 2 capital decrease each year until maturity	20.00%
Number of unrelated parties		2smmf_NumberofUnrelatedParties
Number of issuances		3smmf_SubordinatedDebtNumberofIssuances
Interest rate		10.00%
Number of years subordinated borrowing is not pre-payable		5 years
Term of subordinated borrowing		10 years	7 years 6 months
Basis spread on variable rate	0.50%		2.75%
2009 Subordinated Debt [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Prepaid subordinated debt				6,800,000
2008 Subordinated Debt [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Prepaid subordinated debt				2,500,000
Director [Member]
Debt Instrument [Line Items]
Subordinated debentures		5,000,000
Unrelated Party One [Member]
Debt Instrument [Line Items]
Subordinated debentures		1,000,000
Unrelated Party Two [Member]
Debt Instrument [Line Items]
Subordinated debentures		$ 800,000