Note 9 - Derivatives (Detail) - Derivatives Information - Additional (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Gross Amounts of Assets Presented in the Condensed Consolidated Balance Sheet	$ 7,666	$ 4,940
Net Amount	2,063	3,422
Gross Amounts of Assets Presented in the Condensed Consolidated Balance Sheet	(597)	(365)
Financial Instruments [Member] | Interest Rate Swap [Member]
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	(172)	(92)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	172	92
Financial Instruments [Member]
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	(172)	(92)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	172	92
Cash Collateral Held [Member] | Interest Rate Swap [Member]
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	425	273
Cash Collateral Held [Member] | Swaption [Member]
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	(5,431)	(1,426)
Cash Collateral Held [Member]
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	(5,431)	(1,426)
Gross Amounts Not Offset in the Condensed Consolidated Balance Sheet	425	273
Interest Rate Swap [Member]
Gross Amounts of Assets Presented in the Condensed Consolidated Balance Sheet	2,792	395
Net Amount	2,620	303
Gross Amounts of Assets Presented in the Condensed Consolidated Balance Sheet	(597)	(365)
Swaption [Member]
Gross Amounts of Assets Presented in the Condensed Consolidated Balance Sheet	4,874	4,545
Net Amount	$ (557)	$ 3,119