| Component: (Network and Table) | |
|---|---|
| Network | 100390 - Disclosure - GOODWILL AND OTHER INTANGIBLE ASSETS (Tables) (http://www.investarbank.com/20161231/taxonomy/role/DisclosureGOODWILLANDOTHERINTANGIBLEASSETSTables) |
| Table | (Implied) |
| Reporting Entity [Axis] | 0001602658 (http://www.sec.gov/CIK) |
| Goodwill And Intangible Assets Disclosure [Abstract] | Period [Axis] | ||||||||||||||||||||||||||||||||||||||||
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2016-01-01 - 2016-12-31 | |||||||||||||||||||||||||||||||||||||||||
Goodwill And Intangible Assets Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||
Summary of Core Deposit Intangible Assets Activity | The table below shows a summary of the core deposit intangible assets activity for the periods presented (dollars in thousands).
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