CONSOLIDATED CONDENSED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
ASSETS
Cash and cash equivalents	$ 89,243	$ 118,616
Interest-bearing time deposits	83,228us-gaap_InterestBearingDepositsInBanks	47,520us-gaap_InterestBearingDepositsInBanks
Investment securities available for sale	538,055us-gaap_AvailableForSaleSecurities	549,543us-gaap_AvailableForSaleSecurities
Investment securities held to maturity (fair value of $670,611 and $647,723)	651,418us-gaap_HeldToMaturitySecurities	631,088us-gaap_HeldToMaturitySecurities
Loans held for sale	6,392us-gaap_LoansReceivableHeldForSaleNet	7,235us-gaap_LoansReceivableHeldForSaleNet
Loans, net of allowance for loan losses of $62,801 and $63,964	3,902,731	3,860,901
Premises and equipment	77,468us-gaap_PropertyPlantAndEquipmentNet	77,691us-gaap_PropertyPlantAndEquipmentNet
Federal Reserve and Federal Home Loan Bank stock	41,273	41,353
Interest receivable	19,557us-gaap_InterestReceivable	19,984us-gaap_InterestReceivable
Core deposit intangibles	15,310	16,031
Goodwill	202,724us-gaap_Goodwill	202,724us-gaap_Goodwill
Cash surrender value of life insurance	170,172	169,424
Other real estate owned	19,073	19,293
Tax asset, deferred and receivable	38,695us-gaap_DeferredTaxAssetsNet	41,960us-gaap_DeferredTaxAssetsNet
Other assets	22,182us-gaap_OtherAssets	20,764us-gaap_OtherAssets
TOTAL ASSETS	5,877,521us-gaap_Assets	5,824,127us-gaap_Assets
Deposits:
Noninterest-bearing	1,100,397	1,070,859
Interest-bearing	3,547,678	3,569,835
Total Deposits	4,648,075us-gaap_Deposits	4,640,694us-gaap_Deposits
Borrowings:
Federal funds purchased		15,381us-gaap_FederalFundsPurchased
Securities sold under repurchase agreements	134,023	124,539
Federal Home Loan Bank advances	166,326	145,264
Subordinated debentures and term loans	126,875us-gaap_OtherBorrowings	126,810us-gaap_OtherBorrowings
Total Borrowings	427,224us-gaap_DebtAndCapitalLeaseObligations	411,994us-gaap_DebtAndCapitalLeaseObligations
Interest payable	3,685	3,201
Other liabilities	58,879us-gaap_OtherLiabilities	41,411us-gaap_OtherLiabilities
Total Liabilities	5,137,863us-gaap_Liabilities	5,097,300us-gaap_Liabilities
COMMITMENTS AND CONTINGENT LIABILITIES
STOCKHOLDERS' EQUITY
Preferred Stock, $1,000 par value, $1,000 liquidation value: Authorized - 600 shares Issued and outstanding - 125 shares	125us-gaap_PreferredStockValue	125us-gaap_PreferredStockValue
Common Stock, $.125 stated value: Authorized - 50,000,000 shares Issued and outstanding - 37,781,488 and 37,669,948 shares	4,723us-gaap_CommonStockValue	4,709us-gaap_CommonStockValue
Additional paid-in capital	431,199us-gaap_AdditionalPaidInCapital	431,220us-gaap_AdditionalPaidInCapital
Retained earnings	305,526	292,403
Accumulated other comprehensive loss	(1,915)	(1,630)
Total Stockholders' Equity	739,658us-gaap_StockholdersEquity	726,827us-gaap_StockholdersEquity
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 5,877,521	$ 5,824,127

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.