Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
ASSETS
Cash and due from banks	$ 185,958	$ 228,431
Interest-bearing deposits with banks	1,291,447	1,195,824
Securities held for investment (fair value: $1,223 and $1,433, respectively)	1,217	1,428
Securities available for sale at fair value	723,655	770,704
Loans held for sale	7,719	8,174
Loans (net of unearned interest)	5,042,502	4,975,976
Allowance for loan losses	(52,915)	(51,389)
Loans, net of allowance for loan losses	4,989,587	4,924,587
Premises and equipment, net	177,950	174,362
Other real estate owned	6,172	6,690
Intangible assets, net	15,701	16,470
Goodwill	79,749	79,749
Accrued interest receivable and other assets	229,845	167,839
Total assets	7,709,000	7,574,258
Deposits:
Noninterest-bearing	2,659,584	2,613,876
Interest-bearing	4,046,802	3,991,619
Total deposits	6,706,386	6,605,495
Short-term borrowings	5,200	1,675
Accrued interest payable and other liabilities	42,683	37,495
Junior subordinated debentures	26,804	26,804
Total liabilities	6,781,073	6,671,469
Stockholders' equity:
Common stock, $1.00 par, 40,000,000 shares authorized; shares issued and outstanding: 32,617,788 and 32,603,926, respectively	32,618	32,604
Capital surplus	150,195	149,709
Retained earnings	744,713	722,615
Accumulated other comprehensive loss, net of income tax of $137 and $(731), respectively	401	(2,139)
Total stockholders' equity	927,927	902,789
Total liabilities and stockholders' equity	7,709,000	7,574,258
Senior Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value
Cumulative Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value