Subordinated Debentures And Trust Preferred Securities	12 Months Ended
Dec. 31, 2011
Other Borrowings and Subordinated Debentures And Trust Preferred Securities [Abstract]
Subordinated Debentures And Trust Preferred Securities	NOTE K – SUBORDINATED DEBENTURES AND TRUST PREFERRED SECURITIES In March 2004, Southern Michigan Bancorp Capital Trust I, a trust formed by the Company, closed a pooled private offering of 5,000 trust preferred securities with a liquidation amount of $1,000 per security. The Company issued $5,155,000 of subordinated debentures to the trust in exchange for ownership of all of the common securities of the trust and the proceeds of the preferred securities sold by the trust. The Company is not considered the primary beneficiary of this trust, therefore the trust is not consolidated in the Company’s financial statements, but rather the subordinated debentures are shown as a liability. The Company may redeem the subordinated debentures, subject to the receipt by the Company of the proper approval of the Federal Reserve, if such approval is required under applicable capital guidelines or policies of the Federal Reserve. The subordinated debentures may be redeemed on January 7, April 7, July 7 and October 7 of each year either in whole or in integrals of $1,000 at 100% of the principal amount, plus accrued and unpaid interest. The subordinated debentures mature on April 6, 2034. The subordinated debentures are also redeemable in whole, but not in part, from time to time upon the occurrence of specific events defined within the trust indenture. The Company has the option to defer interest payments on the subordinated debentures from time to time for a period not to exceed 20 consecutive quarters. The $5,000,000 in trust preferred securities may be included in Tier I capital (with certain limitations applicable) under current regulatory guidelines and interpretations. The trust preferred securities and subordinated debentures have a variable rate of interest equal to the three month London Interbank Offered Rate (LIBOR) plus 2.75%. The rate at December 31, 2011 was 3.15%. Interest expense related to the subordinated debentures amounted to $156,000 in 2011, $157,000 in 2010, and $197,000 in 2009. The Company’s investment in the common stock of the trust is $155,000 and is included in other assets.

Subordinated Debentures And Trust Preferred Securities

12 Months Ended

Dec. 31, 2011

Other Borrowings and Subordinated Debentures And Trust Preferred Securities [Abstract]

Subordinated Debentures And Trust Preferred Securities

NOTE K – SUBORDINATED DEBENTURES AND TRUST PREFERRED SECURITIES

In March 2004, Southern Michigan Bancorp Capital Trust I, a trust formed by the Company, closed a pooled private offering of 5,000 trust preferred securities with a liquidation amount of $1,000 per security. The Company issued $5,155,000 of subordinated debentures to the trust in exchange for ownership of all of the common securities of the trust and the proceeds of the preferred securities sold by the trust. The Company is not considered the primary beneficiary of this trust, therefore the trust is not consolidated in the Company’s financial statements, but rather the subordinated debentures are shown as a liability. The Company may redeem the subordinated debentures, subject to the receipt by the Company of the proper approval of the Federal Reserve, if such approval is required under applicable capital guidelines or policies of the Federal Reserve. The subordinated debentures may be redeemed on January 7, April 7, July 7 and October 7 of each year either in whole or in integrals of $1,000 at 100% of the principal amount, plus accrued and unpaid interest. The subordinated debentures mature on April 6, 2034. The subordinated debentures are also redeemable in whole, but not in part, from time to time upon the occurrence of specific events defined within the trust indenture. The Company has the option to defer interest payments on the subordinated debentures from time to time for a period not to exceed 20 consecutive quarters.

The $5,000,000 in trust preferred securities may be included in Tier I capital (with certain limitations applicable) under current regulatory guidelines and interpretations. The trust preferred securities and subordinated debentures have a variable rate of interest equal to the three month London Interbank Offered Rate (LIBOR) plus 2.75%. The rate at December 31, 2011 was 3.15%. Interest expense related to the subordinated debentures amounted to $156,000 in 2011, $157,000 in 2010, and $197,000 in 2009. The Company’s investment in the common stock of the trust is $155,000 and is included in other assets.