Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Assets
Cash and due from banks (noninterest-bearing)	$ 423,819	$ 345,761
Federal funds sold and securities purchased under reverse repurchase agreements	0	7,253
Securities available for sale (at fair value)	2,382,441	2,194,154
Securities held to maturity (fair value: $1,154,606-2014; $1,150,833-2013)	1,155,569	1,168,728
Loans held for sale (LHFS)	120,446	149,169
Loans held for investment (LHFI)	5,923,766	5,798,881
Less allowance for loan losses, LHFI	67,518	66,448
Net LHFI	5,856,248	5,732,433
Acquired loans:
Noncovered loans	713,647	769,990
Covered loans	32,670	34,216
Less allowance for loan losses, acquired loans	10,540	9,636
Net acquired loans	735,777	794,570
Net LHFI and acquired loans	6,592,025	6,527,003
Premises and equipment, net	203,771	207,283
Mortgage servicing rights	67,614	67,834
Goodwill	365,500	372,851
Identifiable intangible assets	39,697	41,990
Other real estate, excluding covered other real estate	111,536	106,539
Covered other real estate	4,759	5,108
FDIC indemnification asset	13,487	14,347
Other assets	576,390	582,363
Total Assets	12,057,054	11,790,383
Deposits:
Noninterest-bearing	2,879,341	2,663,503
Interest-bearing	7,242,778	7,196,399
Total deposits	10,122,119	9,859,902
Federal funds purchased and securities sold under repurchase agreements	259,341	251,587
Short-term borrowings	59,671	66,385
Long-term FHLB advances	8,341	8,458
Subordinated notes	49,912	49,904
Junior subordinated debt securities	61,856	61,856
Other liabilities	121,919	137,338
Total Liabilities	10,683,159	10,435,430
Shareholders' Equity
Common stock, no par value:Authorized: 250,000,000 shares Issued and outstanding: 67,439,562 shares - 2014; 67,372,980 shares - 2013	14,051	14,038
Capital surplus	352,402	349,680
Retained earnings	1,045,939	1,034,966
Accumulated other comprehensive loss, net of tax	(38,497)	(43,731)
Total Shareholders' Equity	1,373,895	1,354,953
Total Liabilities and Shareholders' Equity	$ 12,057,054	$ 11,790,383