Note 18 - Fair Value Measurements (Detail) - Fair Value of Financial Assets Measure on a Recurring Basis (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Available-for-sale securities
Available-for-sale securities	$ 192,165
Assets held in trading accounts	8,368	6,224
US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities
Available-for-sale securities	159,846	152,481
US Government Agencies Debt Securities [Member]
Available-for-sale securities
Available-for-sale securities	159,846	152,481
Mortgage-backed Securities, Issued by Private Enterprises [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities
Available-for-sale securities	15,891	20,634
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Available-for-sale securities
Available-for-sale securities	15,891	20,634
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities
Available-for-sale securities	1,417	2,988
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities
Available-for-sale securities	1,417	2,988
Other Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities
Other securities	1,504	1,504
Other Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities
Other securities	13,507	13,735
Other Securities [Member]
Available-for-sale securities
Other securities	15,011	15,239
Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities
Assets held in trading accounts	1,650	1,800
Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities
Assets held in trading accounts	$ 6,718	$ 4,424

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

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+ Details