Segment Reporting (Schedule Of Segment Reporting Information) (Details) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Interest income	$ 115,477	$ 89,741	$ 198,010	$ 182,119
Interest expense	16,418	21,868	32,187	47,668
Net interest income	99,059	67,873	165,823	134,451
Provision for loan losses	(9,144)	(24,517)	(17,966)	(38,343)
Noninterest income	46,715	35,293	80,899	66,674
Depreciation and amortization	(4,158)	(3,480)	(7,353)	(7,053)
Other noninterest expense	(117,208)	(68,642)	(187,032)	(132,890)
Securities transactions	(36)		(87)
Net income before income taxes	15,228	6,527	34,284	22,839
Income tax expense (benefit)	3,140	27	6,868	2,505
Net income (loss)	12,088	6,500	27,416	20,334
Goodwill	629,688	61,631	629,688	61,631
Total assets	19,757,545	8,500,018	19,757,545	8,500,018	8,138,327
Total interest income from external customers	115,477	89,741	198,010	182,119
Hancock [Member]
Interest income	47,371	52,313	95,001	106,672
Interest expense	8,422	16,176	20,042	35,940
Net interest income	38,949	36,137	74,959	70,732
Provision for loan losses	(3,388)	(14,252)	(10,964)	(25,853)
Noninterest income	26,255	17,647	44,081	32,640
Depreciation and amortization	(2,162)	(2,441)	(4,508)	(4,960)
Other noninterest expense	(44,984)	(39,797)	(84,786)	(75,760)
Securities transactions			(51)
Net income before income taxes	14,670	(2,706)	18,731	(3,201)
Income tax expense (benefit)	3,183	(1,898)	2,570	(3,956)
Net income (loss)	11,487	(808)	16,161	755
Goodwill	23,386	23,386	23,386	23,386
Total assets	5,810,757	5,628,215	5,810,757	5,628,215
Total interest income from affiliates	866	1,253	2,032	2,535
Total interest income from external customers	46,505	51,060	92,969	104,137
LA [Member]
Interest income		33,354		66,702
Interest expense		5,743		11,823
Net interest income		27,611		54,879
Provision for loan losses		(9,481)		(9,738)
Noninterest income		10,914		21,090
Depreciation and amortization		(833)		(1,679)
Other noninterest expense		(20,488)		(40,457)
Net income before income taxes		7,723		24,095
Income tax expense (benefit)		1,740		6,459
Net income (loss)		5,983		17,636
Goodwill		33,763		33,763
Total assets		2,862,112		2,862,112
Total interest income from affiliates		1		9
Total interest income from external customers		33,353		66,693
Whitney [Member]
Interest income	62,731		93,858
Interest expense	5,872		10,069
Net interest income	56,859		83,789
Provision for loan losses	(5,030)		(5,702)
Noninterest income	18,192		27,887
Depreciation and amortization	(1,848)		(2,490)
Other noninterest expense	(68,155)		(90,111)
Securities transactions	20		20
Net income before income taxes	38		13,393
Income tax expense (benefit)	(263)		3,452
Net income (loss)	301		9,941
Goodwill	601,820	33,763	601,820	33,763
Total assets	14,419,232		14,419,232
Total interest income from affiliates	197		204
Total interest income from external customers	62,534		93,654
Other [Member]
Interest income	4,684	5,334	9,633	11,300
Interest expense	1,318	1,094	2,328	2,230
Net interest income	3,366	4,240	7,305	9,070
Provision for loan losses	(726)	(784)	(1,300)	(2,752)
Noninterest income	2,280	6,751	8,950	12,991
Depreciation and amortization	(148)	(206)	(355)	(414)
Other noninterest expense	(4,096)	(8,392)	(12,185)	(16,752)
Securities transactions	(56)		(56)
Net income before income taxes	620	1,609	2,359	2,143
Income tax expense (benefit)	220	185	846	2
Net income (loss)	400	1,424	1,513	2,141
Goodwill	4,482	4,482	4,482	4,482
Total assets	2,770,204	1,143,616	2,770,204	1,143,616
Total interest income from affiliates		6		11
Total interest income from external customers	4,684	5,328	9,633	11,289
Eliminations [Member]
Interest income	691	(1,260)	(482)	(2,555)
Interest expense	806	(1,145)	(252)	(2,325)
Net interest income	(115)	(115)	(230)	(230)
Noninterest income	(12)	(19)	(19)	(47)
Other noninterest expense	(27)	35	50	79
Net income before income taxes	(100)	(99)	(199)	(198)
Net income (loss)	(100)	(99)	(199)	(198)
Total assets	(3,242,648)	(1,133,925)	(3,242,648)	(1,133,925)
Total interest income from affiliates	(1,063)	(1,260)	(2,236)	(2,555)
Total interest income from external customers	$ 1,754		$ 1,754