Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 97,465	$ 116,154
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	21,350	21,533
Provision for loan losses	96,204	22,842
Gain on other real estate owned	(5,145)	(521)
Deferred tax (benefit) expense	(14,713)	11,895
Increase in cash surrender value of life insurance contracts	(8,807)	(7,700)
(Gain) loss on disposal of other assets	(6,014)	1,626
Net (increase) decrease in loans held for sale	(21,698)	498
Net amortization of securities premium/discount	20,836	15,456
Amortization of intangible assets	15,015	18,493
Amortization of FDIC indemnification asset	4,678	4,034
Stock-based compensation expense	10,555	9,469
Increase (decrease) in interest payable and other liabilities	8,502	(6,753)
Net payments (to) from FDIC for loss share claims	(436)	14,667
Decrease in FDIC loss share receivable	3,487	6,309
Decrease (increase) in other assets	40,693	(9,980)
Other, net	6,572	4,768
Net cash provided by operating activities	268,544	222,790
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sales of securities	141,716	9,287
Proceeds from maturities of securities available for sale	298,810	755,663
Purchases of securities available for sale	(720,241)	(1,286,443)
Proceeds from maturities of securities held to maturity	307,633	439,410
Purchases of securities held to maturity	(371,657)	(658,226)
Net decrease in short-term investments	436,635	608,534
Proceeds from sales of loans	166,922
Net increase in loans	(591,696)	(882,702)
Purchase of life insurance contracts	(40,000)
Purchases of property and equipment	(10,817)	(19,529)
Proceeds from sales of property and equipment	677	13,607
Proceeds from sales of other real estate	20,709	39,612
Other, net	(3,651)	(8,603)
Net cash used in investing activities	(364,960)	(989,390)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in deposits	536,581	867,117
Net decrease in short-term borrowings	(347,688)	(102,391)
Repayments of long-term debt	(16,796)	(31,621)
Net proceeds from issuance of long-term debt	6,796	149,153
Dividends paid	(57,349)	(57,881)
Purchase of common stock under stock buyback program		(90,836)
Proceeds from exercise of stock options	49	347
Issuance of stock from dividend reinvestment	821
Net cash provided by financing activities	122,414	733,888
NET INCREASE (DECREASE) IN CASH AND DUE FROM BANKS	25,998	(32,712)
CASH AND DUE FROM BANKS, BEGINNING	303,874	356,455
CASH AND DUE FROM BANKS, ENDING	329,872	323,743
SUPPLEMENTAL INFORMATION FOR NON-CASH INVESTING AND FINANCING ACTIVITIES
Assets acquired in settlement of loans	$ 12,012	$ 12,997