Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Operating Activities:
Net income	$ 152,267	$ 121,238
Adjustments to reconcile net income to net cash used for operating activities
Provision for credit losses	26,734	23,883
Depreciation, amortization and accretion, net	38,798	28,017
Stock-based compensation expense	6,778	7,817
Excess tax benefits from stock-based compensation arrangements	(399)	(660)
Net amortization of premium on securities	3,728	2,576
Accretion of discount on loans	(23,416)	(25,061)
Mortgage servicing rights fair value change, net	(4,810)	641
Originations and purchases of mortgage loans held-for-sale	(3,208,468)	(3,094,901)
Proceeds from sales of mortgage loans held-for-sale	3,111,318	3,182,623
Bank owned life insurance (BOLI), net of claims	(2,613)	(1,683)
Increase in trading securities, net	(644)	(2,106)
Net decrease (increase) in brokerage customer receivables	2,120	(4,072)
Gains on mortgage loans sold	(74,446)	(83,437)
Gains on investment securities, net	(6,070)	(402)
Gains on early extinguishment of debt	(4,305)	0
(Gains) losses on sales of premises and equipment, net	(89)	512
Net losses (gains) on sales and fair value adjustments of other real estate owned	935	(585)
Increase in accrued interest receivable and other assets, net	(131,504)	(113,805)
Increase (decrease) in accrued interest payable and other liabilities, net	31,082	(28,717)
Net Cash (Used for) Provided by Operating Activities	(83,004)	11,878
Investing Activities:
Proceeds from maturities of available-for-sale securities	1,128,428	397,832
Proceeds from maturities of held-to-maturity securities	502	0
Proceeds from sales and calls of available-for-sale securities	2,186,662	1,216,860
Proceeds from calls of held-to-maturity securities	423,866	0
Purchases of available-for-sale securities	(3,169,020)	(1,584,282)
Purchases of held-to-maturity securities	(472,803)	0
(Purchase) redemption of Federal Home Loan Bank and Federal Reserve Bank stock, net	(28,049)	1,274
Net cash paid in business combinations	(578,315)	(15,428)
Proceeds from sales of other real estate owned	29,223	34,936
Proceeds received from the FDIC related to reimbursements on covered assets	2,124	1,697
Net (increase) decrease in interest bearing deposits with banks	(204,085)	438,072
Net increase in loans	(1,303,218)	(1,286,736)
Redemption of BOLI	659	2,701
Purchases of premises and equipment, net	(28,276)	(29,375)
Net Cash Used for Investing Activities	(2,012,302)	(822,449)
Financing Activities:
Increase in deposit accounts	2,408,216	970,090
(Decrease) increase in other borrowings, net	(24,545)	38,775
Decrease in Federal Home Loan Bank advances, net	(440,257)	(293,360)
Proceeds from the issuance of common stock, net	152,823	0
Proceeds from the issuance of preferred stock, net	0	120,842
Redemption of junior subordinated debentures, net	(10,695)	0
Excess tax benefits from stock-based compensation arrangements	399	660
Issuance of common shares resulting from the exercise of stock options and the employee stock purchase plan	9,796	14,413
Common stock repurchases	(549)	(415)
Dividends paid	(28,730)	(20,486)
Net Cash Provided by Financing Activities	2,066,458	830,519
Net (Decrease) Increase in Cash and Cash Equivalents	(28,848)	19,948
Cash and Cash Equivalents at Beginning of Period	275,795	230,707
Cash and Cash Equivalents at End of Period	$ 246,947	$ 250,655