Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
ASSETS
Cash and due from banks	$ 181,863	$ 216,104
Interest-bearing deposits with banks	1,590,240	1,541,771
Federal funds sold	21,097	700
Securities (fair value: $493,108 and $470,006, respectively)	493,101	469,995
Loans held for sale	6,197	6,173
Loans (net of unearned interest)	4,984,484	4,721,995
Allowance for loan losses	(51,550)	(51,666)
Loans, net of allowance for loan losses	4,932,934	4,670,329
Premises and equipment, net	141,163	134,088
Other real estate owned	3,478	4,136
Intangible assets, net	18,782	11,082
Goodwill	79,796	54,042
Accrued interest receivable and other assets	146,991	144,736
Total assets	7,615,642	7,253,156
Deposits:
Noninterest-bearing	2,629,984	2,550,150
Interest-bearing	4,083,068	3,864,895
Total deposits	6,713,052	6,415,045
Short-term borrowings	100	900
Accrued interest payable and other liabilities	32,435	29,623
Junior subordinated debentures	31,959	31,959
Total liabilities	6,777,546	6,477,527
Stockholders' equity:
Common stock, $1.00 par, 40,000,000 shares authorized; shares issued and outstanding: 32,707,166 and 31,894,563, respectively	32,708	31,895
Capital surplus	147,762	107,481
Retained earnings	661,341	638,580
Accumulated other comprehensive loss, net of income tax of $(1,269) and $(795), respectively	(3,715)	(2,327)
Total stockholders' equity	838,096	775,629
Total liabilities and stockholders' equity	7,615,642	7,253,156
Senior Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value
Cumulative Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value