Loan Securitization (Carrying Values And Classification Of The Restricted Assets And Liabilities Relating To The Securitization Activities) (Detail) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Restricted Assets And Liabilities Relating To The Securitization [Line Items]
Interest-bearing deposits with banks-restricted for securitization investors	$ 0	$ 0		$ 529,418,000
Loans, net of unearned income, excluding covered loans	11,900,312,000	11,828,943,000		10,717,384,000
Allowance for loan losses	(110,348,000)	(107,351,000)		(111,023,000)	(110,381,000)
Net loans-restricted for securitization investors	0	0		156,132,000
Total assets	17,074,247,000	17,519,613,000		16,172,018,000
Secured borrowings-owed to securitization investors	0	0	360,800,000	428,000,000
Total liabilities	15,248,559,000	15,714,908,000		14,484,097,000
Unrestricted Assets And Liabilities [Member]
Restricted Assets And Liabilities Relating To The Securitization [Line Items]
Cash collateral	36,000	36,000
Collections and interest funding accounts	0	0
Interest-bearing deposits with banks-restricted for securitization investors	36,000	36,000
Loans, net of unearned income, excluding covered loans	0	0
Allowance for loan losses	0	0
Net loans-restricted for securitization investors	0	0
Other Assets	0	0
Total assets	36,000	36,000
Secured borrowings-owed to securitization investors	0	0
Other Liabilities	0	0
Total liabilities	0	0
Restricted Assets And Liabilities [Member]
Restricted Assets And Liabilities Relating To The Securitization [Line Items]
Cash collateral				2,017,000
Collections and interest funding accounts				527,401,000
Interest-bearing deposits with banks-restricted for securitization investors				529,418,000
Loans, net of unearned income, excluding covered loans				156,793,000
Allowance for loan losses				(661,000)
Net loans-restricted for securitization investors				156,132,000
Other Assets				2,045,000
Total assets				687,595,000
Secured borrowings-owed to securitization investors				600,000,000
Other Liabilities				1,187,000
Total liabilities				$ 601,187,000