Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Operating Activities:
Net income	$ 170,494	$ 140,323
Adjustments to reconcile net income to net cash from operating activities:
Provision for loan losses	16,378	37,689
Deferred tax expense (benefit)	(4,173)	(9,633)
Accretion of loan discount	(7,403)	(8,185)
Securities premium amortization (discount accretion), net	43,652	38,806
Net (gain) loss on securities transactions	50	(14,903)
Depreciation and amortization	24,055	23,823
Net (gain) loss on sale/write-down of assets/foreclosed assets	(1,383)	(596)
Stock-based compensation	6,291	5,477
Net excess tax benefit from stock-based compensation	5,579	65
Earnings on life insurance policies	(1,565)	(1,745)
Net change in:
Trading account securities	(7,120)	177
Accrued interest receivable and other assets	(20,116)	(26,795)
Accrued interest payable and other liabilities	(36,277)	(4,664)
Net cash from operating activities	188,462	179,839
Investing Activities:
Securities held-to-maturity - Purchases	0	0
Securities held-to-maturity - Sales	0	135,610
Securities held to maturity: Maturities, calls and principal repayments	634,874	164,687
Securities available for sale:
Purchases	(8,825,545)	(1,514,263)
Sales	8,247,439	1,060,196
Maturities, calls and principal repayments	164,182	165,883
Proceeds from sale of loans	0	30,470
Net change in loans	(549,408)	(144,192)
Benefits received on life insurance policies	462	591
Proceeds from sales of premises and equipment	1,550	1,516
Purchases of premises and equipment	(14,481)	(23,459)
Proceeds from sales of repossessed properties	345	297
Net cash from investing activities	(340,582)	(122,664)
Financing Activities:
Net change in deposits	(198,002)	(56,144)
Net change in short-term borrowings	(52,125)	(160,362)
Proceeds from issuance of subordinated notes	98,434	0
Principal payments on subordinated notes	(100,000)	0
Proceeds from stock option exercises	44,149	3,586
Purchase of treasury stock	(42)	0
Cash dividends – preferred stock	(4,031)	(4,031)
Cash dividends – common stock	(71,393)	(66,524)
Net cash from financing activities	(283,010)	(283,475)
Net change in cash and cash equivalents	(435,130)	(226,300)
Cash and equivalents at beginning of period	4,141,445	3,591,523
Cash and equivalents at end of period	$ 3,706,315	$ 3,365,223