CONDENSED PARENT COMPANY INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Assets
Other assets	$ 204,502	$ 262,464
Total Assets	12,995,851	13,615,010	13,167,867
Liabilities and shareholders' equity:
Total liabilities	11,732,939	12,392,766
Shareholders' equity	1,262,912	1,222,244	1,276,296	1,240,260
Total Liabilities and Shareholders' Equity	12,995,851	13,615,010
Condensed Statements of Income
Income before tax benefit and equity in undistributed earnings	42,044	14,237	112,834
Income tax benefit	(4,475)	8,705	(30,105)
Net income	37,569	22,942	82,729
Operating activities:
Net income	37,569	22,942	82,729
Net cash provided by operating activities	256,425	223,998	280,025
Investing activities:
Net cash paid for acquisitions	(1,200)	0	(1,130)
Net cash used in investing activities	661,840	(626,851)	144,621
Financing activities:
Cash dividends	(11,689)	(73,457)	(73,335)
Common stock transactions, net	20	420	6,320
Net cash used in financing activities	(691,007)	436,494	(490,798)
(Decrease) increase in Cash and Cash Equivalents	227,258	33,641	(66,152)
Cash and Cash Equivalents at Beginning of Year	272,086	238,445	304,597
Cash and Cash Equivalents at End of Year	499,344	272,086	238,445
BancorpSouth, Inc. (Parent Company Only) [Member]
Assets
Cash on deposit with subsidiary bank	17,100	18,972
Investment in subsidiaries	1,392,966	1,352,569
Other assets	15,173	12,900
Total Assets	1,425,239	1,384,441
Liabilities and shareholders' equity:
Total liabilities	162,327	162,197
Shareholders' equity	1,262,912	1,222,244
Total Liabilities and Shareholders' Equity	1,425,239	1,384,441
Condensed Statements of Income
Dividends from subsidiaries	23,000	89,500	54,000
Other operating income	268	837	1,513
Total income	23,268	90,337	55,513
Operating expenses	17,358	16,807	16,303
Income before tax benefit and equity in undistributed earnings	5,910	73,530	39,210
Income tax benefit	6,050	6,102	5,657
Income before equity in undistributed earnings of subsidiaries	11,960	79,632	44,867
Equity in (distributed) undistributed earnings of subsidiaries	25,609	(56,690)	37,862
Net income	37,569	22,942	82,729
Operating activities:
Net income	37,569	22,942	82,729
Adjustments to reconcile net income to net cash provided by operating activities	(30,348)	58,486	(39,131)
Net cash provided by operating activities	7,221	81,428	43,598
Investing activities:
Net cash paid for acquisitions	0	0	0
Net cash used in investing activities	0	0	0
Financing activities:
Cash dividends	(11,689)	(73,458)	(73,335)
Common stock transactions, net	2,596	464	6,320
Net cash used in financing activities	(9,093)	(72,994)	(67,015)
(Decrease) increase in Cash and Cash Equivalents	(1,872)	8,434	(23,417)
Cash and Cash Equivalents at Beginning of Year	18,972	10,538	33,955
Cash and Cash Equivalents at End of Year	$ 17,100	$ 18,972	$ 10,538