Note 6 - Past Due Loans, Allowance For Credit Losses, and Impaired Loans (Detail) - Allowance for Credit Losses (Continued) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Balance at beginning of period	$ 139,831	$ 145,477	$ 145,072	$ 144,808
Balance at end of period	131,291	145,019	131,291	145,019
Loans charged-off	(29,998)	(35,806)	(79,315)	(80,535)
Recoveries of loans previously charged-off	1,033	1,772	6,854	7,294
Net loans charged-off	(28,965)	(34,034)	(72,461)	(73,241)
Provision for loan losses	20,425	33,576	58,680	73,452
Commercial, Industrial, And Agricultural [Member]
Balance at beginning of period			49,545	54,452
Balance at end of period	48,899	54,997	48,899	54,997
Loans charged-off			(22,815)	(26,376)
Recoveries of loans previously charged-off			2,952	4,796
Net loans charged-off			(19,863)	(21,580)
Provision for loan losses			19,217	22,125
Office Retail And Industrial [Member]
Balance at beginning of period			20,758	20,164
Balance at end of period	16,647	20,179	16,647	20,179
Loans charged-off			(4,395)	(7,434)
Recoveries of loans previously charged-off			60	612
Net loans charged-off			(4,335)	(6,822)
Provision for loan losses			224	6,837
Multi-Family [Member]
Balance at beginning of period			3,996	4,555
Balance at end of period	4,610	3,909	4,610	3,909
Loans charged-off			(9,445)	(1,771)
Recoveries of loans previously charged-off			74	552
Net loans charged-off			(9,371)	(1,219)
Provision for loan losses			9,985	573
Residential Construction [Member]
Balance at beginning of period			27,933	33,078
Balance at end of period	18,071	23,551	18,071	23,551
Loans charged-off			(11,397)	(19,176)
Recoveries of loans previously charged-off			2,830	270
Net loans charged-off			(8,567)	(18,906)
Provision for loan losses			(1,295)	9,379
Other Commerical Real Estate [Member]
Balance at beginning of period			29,869	21,084
Balance at end of period	27,111	28,807	27,111	28,807
Loans charged-off			(17,018)	(17,128)
Recoveries of loans previously charged-off			623	342
Net loans charged-off			(16,395)	(16,786)
Provision for loan losses			13,637	24,509
Consumer [Member]
Balance at beginning of period			12,971	11,475
Balance at end of period	14,930	13,576	14,930	13,576
Loans charged-off			(8,021)	(7,986)
Recoveries of loans previously charged-off			315	698
Net loans charged-off			(7,706)	(7,288)
Provision for loan losses			9,665	9,389
Covered Loans [Member]
Balance at end of period	1,023		1,023
Loans charged-off			(6,224)	(664)
Recoveries of loans previously charged-off				24
Net loans charged-off			(6,224)	(640)
Provision for loan losses			7,247	640
Total Allowance [Member]
Balance at beginning of period			145,072	144,808
Balance at end of period	131,291	145,019	131,291	145,019
Loans charged-off			(79,315)	(80,535)
Recoveries of loans previously charged-off			6,854	7,294
Net loans charged-off			(72,461)	(73,241)
Provision for loan losses			$ 58,680	$ 73,452