Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Operating Activities
Net income	$ 109,756	$ 95,289
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	11,034	21,795
Depreciation, amortization, and accretion, net	28,169	26,342
Deferred income tax expense	58,302	49,891
Decrease (increase) in trading account assets	1,891	(14,205)
Originations of mortgage loans held for sale	(454,708)	(347,327)
Proceeds from sales of mortgage loans held for sale	426,430	325,722
Gain on sales of mortgage loans held for sale, net	(8,988)	(6,522)
Increase in other assets	(38,776)	(8,924)
(Decrease) increase in other liabilities	(34,914)	1,955
Investment securities gains, net	(2,710)	(1,331)
Losses and write-downs on other real estate, net	11,066	8,229
Share-based compensation expense	6,271	4,698
Write-downs on other assets held for sale	0	7,508
Gain on sale of Memphis branches, net	0	(5,789)
Gain on sale of branch property	0	(3,116)
Net cash provided by operating activities	112,823	154,215
Investing Activities
Net cash used in dispositions	0	(90,571)
Net (increase) decrease in interest earning deposits with banks	(6,884)	16,664
Net decrease in federal funds sold and securities purchased under resale agreements	623	1,422
Net increase in interest bearing funds with Federal Reserve Bank	(567,843)	(44,756)
Proceeds from maturities and principal collections of investment securities available for sale	314,239	245,108
Proceeds from sales of investment securities available for sale	82,156	20,815
Purchases of investment securities available for sale	(686,074)	(111,505)
Proceeds from sales of loans and principal repayments on other loans held for sale	21,866	37,300
Proceeds from sale of other real estate	19,348	28,147
Net increase in loans	(445,124)	(594,896)
Net increase in premises and equipment	(8,805)	(23,938)
Proceeds from sale of other assets held for sale	351	241
Net cash used in investing activities	(1,276,147)	(515,969)
Financing Activities
Net increase in demand and savings deposits	1,039,670	208,039
Net increase in certificates of deposit	77,813	100,011
Net increase (decrease) in federal funds purchased and securities sold under repurchase agreements	61,369	(20,292)
Principal repayments on long-term debt	(425,078)	(375,667)
Proceeds from issuance of long-term debt	425,000	600,000
Dividends paid to common shareholders	(26,664)	(19,460)
Dividends paid to preferred shareholders	(5,119)	(5,119)
Stock options exercised	3,271	1,304
Repurchases of common stock	(109,570)	0
Excess tax benefit from share-based compensation	2,378	201
Restricted stock activity	(4,403)	(468)
Net cash provided by financing activities	1,038,667	488,549
(Decrease) increase in cash and cash equivalents	(124,657)	126,795
Cash and cash equivalents at beginning of period	485,489	469,630
Cash and cash equivalents at end of period	360,832	596,425
Supplemental Cash Flow Information
Income tax payments (refunds), net	8,751	4,530
Interest paid	55,747	56,657
Non-cash Investing Activities:
Premises and equipment transferred to other assets held for sale	939	13,037
Loans foreclosed and transferred to other real estate	11,391	25,280
Loans transferred to other loans held for sale at fair value	19,459	31,605
Securities purchased during the period but settled after period-end	47,159	0
Dispositions:
Fair value of non-cash assets sold	0	(100,982)
Fair value of liabilities sold	$ 0	$ (191,553)