Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets
Cash and due from banks	$ 148,690	$ 132,595
Federal funds sold	2,146	563
Interest bearing deposits in banks	550,531	647,299
Total cash and cash equivalents	701,367	780,457
Investment securities:
Available-for-sale	1,533,221	1,456,840
Held-to-maturity (estimated fair values of $554,048 and $607,550 at September 30, 2016 and December 31, 2015, respectively)	539,052	600,665
Total investment securities	2,072,273	2,057,505
Loans held for investment	5,462,936	5,193,321
Mortgage loans held for sale	67,979	52,875
Total loans	5,530,915	5,246,196
Less allowance for loan losses	81,235	76,817
Net loans	5,449,680	5,169,379
Goodwill	212,820	204,523
Premises and equipment, net of accumulated depreciation	191,064	190,812
Company-owned life insurance	197,070	187,253
Other real estate owned (OREO)	9,447	6,254
Accrued interest receivable	31,002	27,729
Core deposit intangibles, net of accumulated amortization	10,546	10,589
Mortgage servicing rights, net of accumulated amortization and impairment reserve	17,322	15,621
Other assets	81,256	78,074
Total assets	8,973,847	8,728,196
Deposits:
Non-interest bearing	1,965,872	1,823,716
Interest bearing	5,362,709	5,265,221
Total deposits	7,328,581	7,088,937
Securities sold under repurchase agreements	476,768	510,635
Accounts payable and accrued expenses	55,050	53,042
Accrued interest payable	5,622	4,960
Deferred tax liability	14,888	9,765
Long-term debt	27,949	27,885
Other borrowed funds	8	2
Subordinated debentures held by subsidiary trusts	82,477	82,477
Total liabilities	7,991,343	7,777,703
Stockholders' equity:
Nonvoting noncumulative preferred stock without par value; authorized 100,000 shares; no shares issued and outstanding as of September 30, 2016 or December 31, 2015	0	0
Common stock	293,960	311,720
Retained earnings	679,722	638,367
Accumulated other comprehensive income, net	8,822	406
Total stockholders' equity	982,504	950,493
Total liabilities and stockholders' equity	$ 8,973,847	$ 8,728,196