CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Assets
Cash and due from banks	$ 586,273	$ 183,227
Due from banks - interest-bearing	554,044	552,719
Federal funds sold and securities purchased under resale agreements	200,000	200,000
Securities available-for-sale - cost $5,324,611 and $6,267,691 at June 30, 2014 and December 31, 2013, respectively:
Securities pledged as collateral	11,721	12,376
Held in portfolio	5,316,771	6,228,741
Securities held-to-maturity - fair value $3,441,984 and $2,883,935 at June 30, 2014 and December 31, 2013, respectively:
Securities pledged as collateral	531,400
Held in portfolio	2,886,953	2,957,843
Trading securities	86,097	82,357
Loans and leases, excluding covered loans	18,474,788	17,170,438
Less: Allowance for loan and lease losses	311,276	302,584
Loans and leases, excluding covered loans, net	18,163,512	16,867,854
Covered loans, net of allowance for loan losses	596,667	700,989
Net loans and leases	18,760,179	17,568,843
Premises and equipment, net	205,168	198,398
Deferred tax asset	208,184	217,990
Goodwill	642,622	642,622
Customer-relationship intangibles, net	37,680	40,621
Affordable housing investments	200,570	188,207
Customers' acceptance liability	2,018	10,521
Other real estate owned ($17,944 and $25,481 covered by FDIC loss share at June 30, 2014 and December 31, 2013, respectively)	22,213	38,092
FDIC indemnification asset	68,038	89,227
Other assets	499,161	506,167
Total assets	30,819,092	29,717,951
Liabilities
Demand deposits	16,690,688	16,058,968
Interest checking deposits	2,196,536	2,467,890
Money market deposits	6,681,238	6,022,457
Savings deposits	469,932	441,521
Time deposits-under $100,000	167,268	176,488
Time deposits-$100,000 and over	445,863	512,113
Total deposits	26,651,525	25,679,437
Short-term borrowings	160,337	3,889
Long-term debt	627,768	735,968
Reserve for off-balance sheet credit commitments	24,787	33,944
Acceptances outstanding	2,018	10,521
Other liabilities	452,955	473,438
Total liabilities	27,919,390	26,937,197
Redeemable noncontrolling interest	46,549	39,768
Commitments and contingencies
Shareholders' equity
Preferred stock, par value $1.00 per share; 5,000,000 shares authorized; 275,000 shares issued at June 30, 2014 and December 31, 2013	267,616	267,616
Common stock, par value $1.00 per share; 75,000,000 shares authorized; 54,956,839 and 54,667,295 shares issued at June 30, 2014 and December 31, 2013, respectively	54,957	54,667
Additional paid-in capital	556,284	541,210
Accumulated other comprehensive income (loss)	2,100	(15,641)
Retained earnings	1,994,646	1,918,163
Treasury shares, at cost - 385,163 and 483,523 shares at June 30, 2014 and December 31, 2013, respectively	(22,450)	(25,029)
Total common shareholders' equity	2,585,537	2,473,370
Total shareholders' equity	2,853,153	2,740,986
Total liabilities and shareholders' equity	$ 30,819,092	$ 29,717,951