CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Interest income:
Interest and fees on loans	$ 47,606	$ 48,590	$ 141,136	$ 143,305
Interest and dividends on taxable investments	13,394	16,762	41,176	48,487
Interest and dividends on nontaxable investments	5,132	6,042	15,885	17,658
Total interest income	66,132	71,394	198,197	209,450
Interest expense:
Interest on deposits	2,530	4,402	8,375	14,291
Interest on borrowings	2,368	7,535	10,473	22,648
Interest on subordinated debt held by unconsolidated subsidiary trusts	633	682	1,891	2,056
Total interest expense	5,531	12,619	20,739	38,995
Net interest income	60,601	58,775	177,458	170,455
Provision for loan losses	2,093	2,643	4,807	6,442
Net interest income after provision for loan losses	58,508	56,132	172,651	164,013
Noninterest income:
Deposit service fees	12,703	12,057	36,643	33,461
Other banking services	1,671	1,405	3,729	3,295
Benefit trust, administration, consulting and actuarial fees	9,397	8,912	28,564	26,549
Wealth management services	3,823	3,194	11,566	9,427
Gain on sales of investment securities	0	291	63,799	291
Loss on debt extinguishments	0	0	(63,500)	0
Total noninterest income	27,594	25,859	80,801	73,023
Noninterest expenses:
Salaries and employee benefits	30,448	28,126	91,217	82,395
Occupancy and equipment	6,448	6,541	20,263	19,134
Data processing and communications	6,998	6,085	20,334	17,502
Amortization of intangible assets	1,089	1,212	3,408	3,343
Legal and professional fees	1,897	1,703	5,363	5,650
Office supplies and postage	1,566	1,345	4,579	4,195
Business development and marketing	1,973	1,312	5,256	4,360
FDIC insurance premiums	923	919	2,923	2,728
Acquisition expenses	71	4,796	71	5,221
Other	3,631	4,046	10,558	10,330
Total noninterest expenses	55,044	56,085	163,972	154,858
Income before income taxes	31,058	25,906	89,480	82,178
Income taxes	9,069	7,539	26,128	23,914
Net income	$ 21,989	$ 18,367	$ 63,352	$ 58,264
Basic earnings per share (in dollars per share)	$ 0.55	$ 0.46	$ 1.58	$ 1.48
Diluted earnings per share (in dollars per share)	$ 0.54	$ 0.46	$ 1.56	$ 1.46