CONDENSED PARENT COMPANY INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Assets
Other assets	$ 184,538	$ 204,502
Total Assets	13,397,198	12,995,851	13,615,010
Liabilities and shareholders' equity:
Total liabilities	11,948,146	11,732,939
Shareholders' equity	1,449,052	1,262,912	1,222,244	1,276,296
Total Liabilities and Shareholders' Equity	13,397,198	12,995,851
Condensed Statements of Income [Abstract]
Income before income taxes	117,547	42,044	14,237
Income tax benefit	(33,252)	(4,475)	8,705
Net Income	84,295	37,569	22,942
Operating activities:
Net income	84,295	37,569	22,942
Net cash provided by operating activities	133,331	256,425	223,998
Investing activities:
Net cash paid for acquisitions	0	(1,200)	0
Net cash provided by (used in) investing activities	292,473	661,840	(626,851)
Financing activities:
Cash dividends	(3,778)	(11,689)	(73,457)
Common stock transactions, net	110,229	20	420
Net cash provided by (used in) financing activities	278,466	(691,007)	436,494
Increase in Cash and Cash Equivalents	704,270	227,258	33,641
Cash and Cash Equivalents at Beginning of Year	499,344	272,086	238,445
Cash and Cash Equivalents at End of Year	1,203,614	499,344	272,086
BancorpSouth, Inc. (Parent Company Only) [Member]
Assets
Cash on deposit with subsidiary bank	114,394	17,100
Investment in subsidiaries	1,484,097	1,392,966
Other assets	13,398	15,173
Total Assets	1,611,889	1,425,239
Liabilities and shareholders' equity:
Total liabilities	162,837	162,327
Shareholders' equity	1,449,052	1,262,912
Total Liabilities and Shareholders' Equity	1,611,889	1,425,239
Condensed Statements of Income [Abstract]
Dividends from subsidiaries	0	23,000	89,500
Other operating income	1,253	268	837
Total income	1,253	23,268	90,337
Operating expenses	16,931	17,358	16,807
Income before income taxes	(15,678)	5,910	73,530
Income tax benefit	5,732	6,050	6,102
Income (loss) before equity in undistributed earnings of subsidiaries	(9,946)	11,960	79,632
Equity in undistributed (distributed) earnings of subsidiaries	94,241	25,609	(56,690)
Net Income	84,295	37,569	22,942
Operating activities:
Net income	84,295	37,569	22,942
Adjustments to reconcile net income to net cash provided by operating activities	(95,231)	(30,348)	58,486
Net cash provided by operating activities	(10,936)	7,221	81,428
Investing activities:
Net cash paid for acquisitions	0	0	0
Net cash provided by (used in) investing activities	0	0	0
Financing activities:
Cash dividends	(3,778)	(11,689)	(73,458)
Common stock transactions, net	112,008	2,596	464
Net cash provided by (used in) financing activities	108,230	(9,093)	(72,994)
Increase in Cash and Cash Equivalents	97,294	(1,872)	8,434
Cash and Cash Equivalents at Beginning of Year	17,100	18,972	10,538
Cash and Cash Equivalents at End of Year	$ 114,394	$ 17,100	$ 18,972