SUMMARY OF ORGANIZATION	9 Months Ended
Sep. 30, 2012
Summary Of Organization [Abstract]
SUMMARY OF ORGANIZATION	NOTE B — SUMMARY OF ORGANIZATION The First Bancshares, Inc., Hattiesburg, Mississippi (the "Company"), was incorporated June 23, 1995, under the laws of the State of Mississippi for the purpose of operating as a bank holding company. The Company’s primary asset is its interest in its wholly-owned subsidiary, The First, A National Banking Association (the Bank). At September 30, 2012, the Company had approximately $725.7 million in assets, $393.0 million in loans, $621.9 million in deposits, and $65.4 million in stockholders' equity. For the nine months ended September 30, 2012, the Company reported net income of $2.9 million ($2.6 million applicable to common stockholders). In the first, second and third quarters of 2012, the Company declared and paid a dividend of $.0375 per common share.

The entire disclosure for the nature of an entity's business, the major products or services it sells or provides and its principal markets, including the locations of those markets. If the entity operates in more than one business, the disclosure also indicates the relative importance of its operations in each business and the basis for the determination (for example, assets, revenues, or earnings).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6003-108592

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 94-6

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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