Consolidated Statements Of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
CASH FLOWS FROM OPERATING ACTIVITIES:
Net earnings	$ 32,815	$ 27,915
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	3,600	3,526
Provision for loan losses	4,051	4,983
Securities premium amortization (discount accretion), net	3,392	2,086
Gain on sale of assets, net	647	(130)
Deferred federal income tax expense	(160)	(659)
Net (increase) decrease in loans held for sale	8,903	(1,677)
Change in other assets	376	1,625
Change in other liabilities	3,125	2,396
Total adjustments	23,934	12,150
Net cash provided by operating activities	56,749	40,065
CASH FLOWS FROM INVESTING ACTIVITIES:
Sales	12,436	15,018
Maturities	168,863	83,344
Purchases	(265,097)	(227,495)
Activity in held-to-maturity securities - maturities	2,402	4,169
Net increase in loans	(42,302)	(15,723)
Purchases of bank premises and equipment and computer software	(6,437)	(5,763)
Proceeds from sale of other assets	1,495	3,791
Net cash used in investing activities	(128,640)	(142,659)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase (decrease) in noninterest-bearing deposits	29,797	(54,157)
Net increase (decrease) in interest-bearing deposits	(23,658)	75,628
Net increase in short-term borrowings	14,008	13,386
Common stock transactions:
Proceeds from stock issuances	805	569
Dividends paid	(14,231)	(14,167)
Net cash provided by financing activities	6,721	21,259
NET DECREASE IN CASH AND CASH EQUIVALENTS	(65,170)	(81,335)
CASH AND CASH EQUIVALENTS, beginning of period	367,953	321,541
CASH AND CASH EQUIVALENTS, end of period	302,783	240,206
SUPPLEMENTAL INFORMATION AND NONCASH TRANSACTIONS
Interest paid	4,927	7,357
Federal income tax paid	9,231	8,502
Transfer of loans to foreclosed assets	2,581	8,456
Investment securities purchased but not settled	$ 11,168	$ 4,054