Condensed Parent Company Information (Condensed Statements of Cash Flows) (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 16, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net cash provided by operating activities		$ 411,085	$ 343,915	$ 235,730
Proceeds from principal paydowns of securities available for sale		213,877	173,215	9,289
Other, net		(6,824)	825	(3,604)
Net cash used in investing activities		(895,321)	(1,321,031)	(2,276,431)
Proceeds from issuance of long term debt		165	6,838	273,565
Repayments of long term debt		(204,111)	(21,271)	(157,933)
Dividends paid to stockholders		(83,266)	(76,551)	(77,013)
Repurchase of common stock				(95,613)
Proceeds from issuance of common stock	$ 259,000		259,299
Payroll tax remitted on net share settlement of equity awards		(11,881)	(3,178)	(3,385)
Net cash provided by financing activities		498,495	1,045,931	1,988,120
NET INCREASE (DECREASE) IN CASH AND DUE FROM BANKS		14,259	68,815	(52,581)
CASH AND DUE FROM BANKS, BEGINNING		372,689	303,874	356,455
CASH AND DUE FROM BANKS, ENDING		386,948	372,689	303,874
Hancock Holding Company [Member]
Cash flows from operating activities - principally dividends received from subsidiaries		111,591	122,528	33,912
Net cash provided by operating activities		111,591	122,528	33,912
Contribution of capital to subsidiary		(270,000)	(21,000)	(90)
Proceeds from principal paydowns of securities available for sale		11,015	13,827	12,863
Other, net				1,629
Net cash used in investing activities		(258,985)	(7,173)	14,402
Proceeds from issuance of long term debt				269,004
Repayments of long term debt		(17,900)	(17,900)	(149,600)
Dividends paid to stockholders		(83,266)	(77,012)	(77,474)
Repurchase of common stock				(95,613)
Proceeds from issuance of common stock		15,312	262,961	347
Payroll tax remitted on net share settlement of equity awards		(11,881)	(3,178)	(3,385)
Other, net			(133)
Net cash provided by financing activities		(97,735)	164,738	(56,721)
NET INCREASE (DECREASE) IN CASH AND DUE FROM BANKS		(245,129)	280,093	(8,407)
CASH AND DUE FROM BANKS, BEGINNING		316,457	36,364	44,771
CASH AND DUE FROM BANKS, ENDING		$ 71,328	$ 316,457	$ 36,364