Consolidated Balance Sheets - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets:
Cash and due from banks	$ 333,775	$ 372,689
Interest-bearing bank deposits	105,428	77,235
Federal funds sold	6,297	942
Securities available for sale, at fair value (amortized cost of $2,879,343 and $2,562,000)	2,855,278	2,516,908
Securities held to maturity (fair value of $2,768,148 and $2,470,117)	2,769,274	2,500,220
Loans held for sale	23,236	34,064
Loans	18,786,285	16,752,151
Less: allowance for loan losses	(223,122)	(229,418)
Loans, net	18,563,163	16,522,733
Property and equipment, net of accumulated depreciation of $226,410 and $231,127	365,145	361,612
Prepaid expenses	25,084	18,038
Other real estate, net	21,154	18,884
Accrued interest receivable	78,011	65,887
Goodwill	739,403	621,193
Other intangible assets, net	96,525	87,757
Life insurance contracts	539,232	480,406
FDIC loss share receivable		16,219
Deferred tax asset, net	83,615	104,435
Other assets	212,135	176,080
Total assets	26,816,755	23,975,302
Deposits:
Noninterest-bearing	7,896,384	7,658,203
Interest-bearing	13,637,475	11,766,063
Total deposits	21,533,859	19,424,266
Short-term borrowings	1,737,151	1,225,406
Long-term debt	331,179	436,280
Accrued interest payable	9,014	9,574
Other liabilities	342,277	160,008
Total liabilities	23,953,480	21,255,534
Stockholders' equity:
Common Stock	291,358	291,358
Capital surplus	1,721,477	1,698,253
Retained earnings	948,591	850,689
Accumulated other comprehensive loss, net	(98,151)	(120,532)
Total stockholders' equity	2,863,275	2,719,768
Total liabilities and stockholders' equity	$ 26,816,755	$ 23,975,302
Common shares authorized (par value of 3.33 per share)	350,000	350,000
Common shares issued	87,495	87,495
Common shares outstanding	84,767	84,235