Number of Statutory Business Trusts

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- Definition

Trust preferred securities limited to tier one capital elements, net of goodwill.

+ 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.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ 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

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- Definition

The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

+ References

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Borrowed Funds (Subordinated Debentures Owed to Unconsolidated Subsidiary Trusts) (Narrative) (Details) (USD $)	12 Months Ended				1 Months Ended
	Dec. 31, 2014 trust	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2008	Oct. 31, 2002	Mar. 31, 2004	Dec. 31, 2005
Debt Instrument [Line Items]
Number of Statutory Business Trusts	3smmf_NumberofStatutoryBusinessTrusts
Subordinated debentures owed to unconsolidated subsidiary trusts	$ 19,589,000	$ 19,589,000
Ownership percentage	100.00%
Net proceeds from issuance of common stock	7,822,000	0	0
Basis spread on variable rate	0.50%			2.75%
Trust preferred securities limited to tier one capital elements, Nnt of goodwill	25.00%
Sfg Capital Trust I [Member]
Debt Instrument [Line Items]
Proceeds from issuance or sale of equity					3,500,000
Net proceeds from issuance of common stock					109,000
Payments to acquire investments					3,610,000
Basis spread on variable rate					3.45%
Sfg Capital Trust Ii [Member]
Debt Instrument [Line Items]
Proceeds from issuance or sale of equity						7,500,000
Net proceeds from issuance of common stock						232,000
Payments to acquire investments						7,730,000
Basis spread on variable rate						2.80%
Sfg Capital Trust Iii [Member]
Debt Instrument [Line Items]
Proceeds from issuance or sale of equity							8,000,000
Net proceeds from issuance of common stock							248,000
Payments to acquire investments							$ 8,250,000
Basis spread on variable rate							1.45%