CONDENSED PARENT COMPANY INFORMATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Assets
Other assets	$ 186,775	$ 156,690
Total Assets	13,798,662	13,326,369	$ 13,029,733
Liabilities and shareholders' equity:
Total liabilities	12,143,218	11,720,310
Shareholders' equity	1,655,444	1,606,059	1,513,130	$ 1,449,052
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	13,798,662	13,326,369
Condensed Statements of Income [Abstract]
Income before income taxes	186,739	167,402	131,666
Income tax benefit	(59,248)	(50,652)	(37,551)
Net Income	127,491	116,750	94,115
Operating activities:
Net income	127,491	116,750	94,115
Net cash provided by operating activities	133,306	142,129	203,732
Investing activities:
Net cash (used in) provided by investing activities	(627,004)	(459,359)	(480,032)
Financing activities:
Cash dividends	(33,368)	(23,983)	(11,383)
Redemption of junior subordinated debt securities		(8,248)	(128,866)
Advance of long-term debt		8,000	50,000
Repayment of long-term debt	(8,373)	(8,066)	(1,786)
Common stock transactions, net	10,441	11,583	912
Net cash (used in) provided by financing activities	334,417	146,057	(398,891)
(Decrease) increase in Cash and Cash Equivalents	(159,281)	(171,173)	(675,191)
Cash and Cash Equivalents at Beginning of Year	357,250	528,423	1,203,614
Cash and Cash Equivalents at End of Year	197,969	357,250	528,423
BancorpSouth, Inc. (Parent Company Only) [Member]
Assets
Cash on deposit with subsidiary bank	86,767	93,270
Investment in subsidiaries	1,623,640	1,576,708
Other assets	11,237	10,404
Total Assets	1,721,644	1,680,382
Liabilities and shareholders' equity:
Total liabilities	66,200	74,323
Shareholders' equity	1,655,444	1,606,059
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	1,721,644	1,680,382
Condensed Statements of Income [Abstract]
Dividends from subsidiaries	100,000	60,000	35,000
Other operating income	1,075	585	1,775
Total income	101,075	60,585	36,775
Operating expenses	8,419	6,867	15,033
Income before income taxes	92,656	53,718	21,742
Income tax benefit	2,818	2,420	5,860
Income (loss) before equity in undistributed earnings of subsidiaries	95,474	56,138	27,602
Equity in undistributed (distributed) earnings of subsidiaries	32,017	60,612	66,513
Net Income	127,491	116,750	94,115
Operating activities:
Net income	127,491	116,750	94,115
Adjustments to reconcile net income to net cash provided by operating activities	(32,255)	(61,862)	(62,419)
Net cash provided by operating activities	95,236	54,888	31,696
Financing activities:
Cash dividends	(33,368)	(23,983)	(11,383)
Redemption of junior subordinated debt securities		(8,248)	(128,866)
Advance of long-term debt		8,000	50,000
Repayment of long-term debt	(8,373)	(8,066)	(1,786)
Common stock transactions, net	(59,998)	13,928	2,696
Net cash (used in) provided by financing activities	(101,739)	(18,369)	(89,339)
(Decrease) increase in Cash and Cash Equivalents	(6,503)	36,519	(57,643)
Cash and Cash Equivalents at Beginning of Year	93,270	56,751	114,394
Cash and Cash Equivalents at End of Year	$ 86,767	$ 93,270	$ 56,751