Note 5 - Loans (Detail) - Activity in the Allowance for Credit Losses (USD $) In Thousands, unless otherwise specified	3 Months Ended						12 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
(Reversal)/provision for credit losses	$ (5,000)	$ (4,000)	$ 2,000	$ 9,000	$ 10,000	$ 6,000	$ (9,000)	$ 27,000	$ 156,900
Transfers from reserve for off-balance sheet credit commitments							706	268	2,870
Loans charged off							(32,791)	(77,626)	(138,755)
Recoveries of charged off loans							18,127	11,407	12,327
Reserve for Off-Balance Sheet Credit Commitments [Member] | Beginning of Period [Member]
Balance			2,337				2,069	2,337	5,207
Reserve for Off-Balance Sheet Credit Commitments [Member] | End of Period [Member]
Balance			2,069				1,363	2,069	2,337
Reserve for Off-Balance Sheet Credit Commitments [Member]
(Reversal)/provision for credit losses							(706)	(268)	(2,870)
Beginning of Period [Member]
Balance			245,231				206,280	245,231	211,889
End of Period [Member]
Balance			$ 206,280				$ 183,322	$ 206,280	$ 245,231