Allowance For Loan Losses And Reserve For Unfunded Commitments (Allowance For Loan Losses And Recorded Investment In Loans) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Balance at beginning of period	$ 183,844	$ 218,237	$ 191,594	$ 222,821
Loans charged-off	(33,872)	(45,317)	(73,598)	(87,608)
Recoveries on loans previously charged-off	6,927	1,641	11,268	2,642
Net charge-offs	(26,945)	(43,676)	(62,330)	(84,966)
Provision (release) for loan losses	17,403	31,725	45,038	68,431
Balance at end of period	174,302	206,286	174,302	206,286
Commercial Loan [Member]
Balance at beginning of period	59,911	64,695	60,663	70,115
Loans charged-off	(7,769)	(10,512)	(17,318)	(14,712)
Recoveries on loans previously charged-off	634	707	2,313	1,172
Net charge-offs	(7,135)	(9,805)	(15,005)	(13,540)
Provision (release) for loan losses	12,409	1,462	19,527	(223)
Balance at end of period	65,185	56,352	65,185	56,352
Commercial Real Estate [Member]
Balance at beginning of period	97,021	114,186	94,905	110,853
Loans charged-off	(17,924)	(25,402)	(43,204)	(54,811)
Recoveries on loans previously charged-off	4,150	511	6,032	783
Net charge-offs	(13,774)	(24,891)	(37,172)	(54,028)
Provision (release) for loan losses	1,239	22,240	26,753	54,710
Balance at end of period	84,486	111,535	84,486	111,535
Construction Loans [Member]
Balance at beginning of period	3,180	24,098	12,852	19,778
Loans charged-off	(828)	(8,275)	(2,073)	(8,337)
Recoveries on loans previously charged-off	1,664	56	1,705	153
Net charge-offs	836	(8,219)	(368)	(8,184)
Provision (release) for loan losses	(1,235)	1,852	(9,703)	6,137
Balance at end of period	2,781	17,731	2,781	17,731
Residential Real Estate [Member]
Balance at beginning of period	6,560	5,973	6,376	5,321
Loans charged-off	(1,006)	(186)	(2,090)	(572)
Recoveries on loans previously charged-off	2	40	13	42
Net charge-offs	(1,004)	(146)	(2,077)	(530)
Provision (release) for loan losses	1,273	1,238	2,530	2,274
Balance at end of period	6,829	7,065	6,829	7,065
Home Equity Line of Credit [Member]
Balance at beginning of period	6,601	4,833	4,022	5,764
Loans charged-off	(4)	(508)	(487)	(1,955)
Recoveries on loans previously charged-off	314	15	340	25
Net charge-offs	310	(493)	(147)	(1,930)
Provision (release) for loan losses	153	2,286	3,189	2,792
Balance at end of period	7,064	6,626	7,064	6,626
Consumer Loan [Member]
Balance at beginning of period	10,571	4,452	12,776	10,990
Loans charged-off	(6,341)	(434)	(8,426)	(7,221)
Recoveries on loans previously charged-off	163	312	865	467
Net charge-offs	(6,178)	(122)	(7,561)	(6,754)
Provision (release) for loan losses	3,564	2,647	2,742	2,741
Balance at end of period	$ 7,957	$ 6,977	$ 7,957	$ 6,977