Note 2 - Investments (Detail) - Unrealized Gains and Losses in Investments (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Amortized Cost	$ 355,603	$ 348,190
Unrealized Gains	5,581	5,658
Unrealized Losses	(248)	(170)
Carrying Value	360,936	353,678
US Government Agencies Debt Securities [Member]
Amortized Cost	99,000	105,629
Unrealized Gains	1,082	1,271
Unrealized Losses	(6)	(15)
Carrying Value	100,076	106,885
US States and Political Subdivisions Debt Securities [Member]
Amortized Cost	148,135	116,123
Unrealized Gains	1,684	1,786
Unrealized Losses	(211)	(95)
Carrying Value	149,608	117,814
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Amortized Cost	58,917	64,550
Unrealized Gains	1,789	1,729
Unrealized Losses	0	(2)
Carrying Value	60,706	66,277
Collateralized Mortgage Obligations [Member]
Amortized Cost	47,919	60,278
Unrealized Gains	807	810
Unrealized Losses	(31)	(58)
Carrying Value	48,695	61,030
Equity Securities, Other [Member]
Amortized Cost	1,632	1,610
Unrealized Gains	219	62
Unrealized Losses	0	0
Carrying Value	$ 1,851	$ 1,672

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details