Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
OPERATIONS:
Net interest income	$ 198,031	$ 118,923	$ 309,379	$ 237,710
Provision for Loan, Lease, and Other Losses	7,309	12,196	17,256	26,257
Noninterest Income	69,439	55,301	126,832	107,027
Other expenses	189,640	119,077	296,565	232,845
Net income	48,450	30,585	85,796	60,929
AVERAGES :
Assets	22,810,702	14,558,514		14,527,512
Total commercial
OPERATIONS:
Net interest income	109,705	64,476	175,224	128,329
Provision for Loan, Lease, and Other Losses	2,120	3,465	6,886	12,570
Noninterest Income	20,895	18,047	40,127	32,356
Other expenses	51,891	40,128	94,918	83,479
Net income	49,783	25,304	73,805	42,013
AVERAGES :
Assets	8,852,267	6,364,148		6,346,311
Retail [Member]
OPERATIONS:
Net interest income	89,701	53,287	136,132	107,564
Provision for Loan, Lease, and Other Losses	2,101	1,728	6,174	4,265
Noninterest Income	33,330	24,177	57,718	49,443
Other expenses	85,512	56,784	138,419	115,830
Net income	23,021	12,319	32,016	23,992
AVERAGES :
Assets	5,006,423	2,918,710		2,914,532
Wealth [Member]
OPERATIONS:
Net interest income	3,774	4,590	7,549	9,189
Provision for Loan, Lease, and Other Losses	(42)	(24)	166	201
Noninterest Income	12,821	8,392	21,131	16,460
Other expenses	13,832	9,792	24,006	20,007
Net income	1,824	2,090	2,930	3,536
AVERAGES :
Assets	263,454	237,548		237,060
Nonreportable segments and reconciling items [Member]
OPERATIONS:
Net interest income	(5,149)	(3,430)	(9,526)	(7,372)
Provision for Loan, Lease, and Other Losses	3,130	7,027	4,030	9,221
Noninterest Income	2,393	4,685	7,856	8,768
Other expenses	38,405	12,373	39,222	13,529
Net income	(26,178)	(9,128)	(22,955)	(8,612)
AVERAGES :
Assets	$ 8,688,558	$ 5,038,108		$ 5,029,609