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LONG-TERM DEBT (Narrative) (Details) (USD $)	12 Months Ended
LONG-TERM DEBT (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2002
Debt Instrument [Line Items]
Redemption date	Aug. 12, 2013
Credit Agreement borrowing capacity		$ 696,000,000
Long-term borrowings	81,714,000us-gaap_LongTermDebt	78,148,000us-gaap_LongTermDebt
Unsecured Revolving Loan [Member]
Debt Instrument [Line Items]
Interest rate		2.03%
Maturity date		Aug. 08, 2015
Credit Agreement borrowing capacity		25,000,000
Multi-Draw Term Loan [Member]
Debt Instrument [Line Items]
Maturity date		Aug. 08, 2018
Credit Agreement borrowing capacity		60,000,000
U. S. Bank [Member]
Debt Instrument [Line Items]
Long-term borrowings		48,200,000
Federal Home Loan Bank [Member]
Debt Instrument [Line Items]
Long-term borrowings		30,000,000
Junior Subordinated Debt Securities of BancorpSouth Capital Trust I [Member]
Debt Instrument [Line Items]
Junior Subordinated Debt Securities			128,900,000
Interest rate			8.15%
Number of shares of trust preferred securities			5,000,000
Trust preferred securities, value per share			$ 25
Write-off of unamortized issuance costs		$ 2,900,000