Cover - shares	6 Months Ended
Jun. 30, 2019	Aug. 06, 2019
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Period End Date	Jun. 30, 2019
Entity Registrant Name	MIDSOUTH BANCORP INC
Entity CIK	0000745981
Current Fiscal Year End Date	--12-31
Fiscal Year Focus	2019
Fiscal Period Focus	Q2
Filer Category	Accelerated Filer
Entity Small Business	true
Entity Current Reporting Status	Yes
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		16,732,149

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End date of current fiscal year in the format --MM-DD.

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The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation 12B
-Number 240
-Section 12
-Subsection b-2

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