REGULATORY MATTERS (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
REGULATORY MATTERS [Abstract]
Tier one core capital required for capital adequacy to risk-weighted assets (in hundredths)	4.00%
Tier one total capital required for capital adequacy to risk-weighted assets (in hundredths)	8.00%
Tier one leverage ratio required for capital adequacy to average assets (in hundredths)	4.00%
Tier one risk based capital required to be well capitalized to risk-weighted assets (in hundredths)	6.00%
Total capital required to be well capitalized to risk-weighted assets (in hundredths)	10.00%
Tier one leverage capital required to be well capitalized to average assets (in hundredths)	5.00%
Tier I capital (to risk-weighted assets) [Abstract]
Tier I capital	$ 1,316,905	$ 1,129,746
Tier I capital to risk-weighted assets (in hundredths)	13.77%	11.77%
Total capital (to risk-weighted assets) [Abstract]
Total capital	1,437,320	1,250,801
Total capital to risk-weighted assets (in hundredths)	15.03%	13.03%
Tier I leverage capital (to average assets) [Abstract]
Tier I leverage capital	1,316,905	1,129,746
Tier I leverage capital to average assets (in hundredths)	10.25%	8.85%
BancorpSouth Bank [Member]
Tier I capital (to risk-weighted assets) [Abstract]
Tier I capital	1,191,567	1,099,369
Tier I capital to risk-weighted assets (in hundredths)	12.48%	11.46%
Total capital (to risk-weighted assets) [Abstract]
Total capital	1,311,840	1,220,424
Total capital to risk-weighted assets (in hundredths)	13.74%	12.73%
Tier I leverage capital (to average assets) [Abstract]
Tier I leverage capital	$ 1,191,567	$ 1,099,369
Tier I leverage capital to average assets (in hundredths)	9.34%	8.67%

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The amount of total capital as defined in the regulations.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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