Consolidated Balance Sheets - USD ($) shares in Thousands, $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets:
Cash and due from banks	$ 365,225	$ 372,689
Interest-bearing bank deposits	125,577	77,235
Federal funds sold	851	942
Securities available for sale, at fair value (amortized cost of $2,824,787 and $2,562,000)	2,794,382	2,516,908
Securities held to maturity (fair value of $2,866,529 and $2,470,117)	2,874,454	2,500,220
Loans held for sale	26,787	34,064
Loans	18,473,841	16,752,151
Less: allowance for loan losses	(221,865)	(229,418)
Loans, net	18,251,976	16,522,733
Property and equipment, net of accumulated depreciation of $237,304 and $231,127	365,345	361,612
Prepaid expenses	24,985	18,038
Other real estate, net	17,996	18,884
Accrued interest receivable	75,787	65,887
Goodwill	740,265	621,193
Other intangible assets, net	101,694	87,757
Life insurance contracts	536,912	480,406
FDIC loss share receivable	3,234	16,219
Deferred tax asset, net	89,882	104,435
Other assets	235,217	176,080
Total assets	26,630,569	23,975,302
Deposits:
Noninterest-bearing	7,887,867	7,658,203
Interest-bearing	13,554,948	11,766,063
Total deposits	21,442,815	19,424,266
Short-term borrowings	1,810,907	1,225,406
Long-term debt	407,876	436,280
Accrued interest payable	8,024	9,574
Other liabilities	146,985	160,008
Total liabilities	23,816,607	21,255,534
Stockholders' equity:
Common Stock	291,358	291,358
Capital surplus	1,716,584	1,698,253
Retained earnings	910,459	850,689
Accumulated other comprehensive loss, net	(104,439)	(120,532)
Total stockholders' equity	2,813,962	2,719,768
Total liabilities and stockholders' equity	$ 26,630,569	$ 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	84,738	84,235