Note 5 - Investment Securities (Detail) - Fair Values and Unrealized Losses of the Investment Portfolio (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Available for Sale:
Available for sale securities less than 12 months fair value	$ 3,493	$ 4,784
Available for sale securities less than 12 months unrealized losses	13	101
Available for sale securities 12 months or more fair value	240	117
Available for sale securities 12 months or more unrealized losses	120	73
Available for sale securities fair value	3,733	4,901
Available for sale securities unrealized losses	133	174
Held to Maturity:
Held to maturity securities less than 12 months fair value	896	2,993
Held to maturity securities less than 12 months unrealized losses	104	7
Held to maturity securities 12 months or more fair value	2,918	2,848
Held to maturity securities 12 months or more unrealized losses	82	152
Held to maturity securities fair value	3,814	5,841
Held to maturity securities unrealized losses	186	159
Securities less than 12 months fair value	4,389	7,777
Securities less than 12 months unrealized losses	117	108
Securities 12 months or more fair value	3,158	2,965
Securities 12 months or more unrealized losses	202	225
Securities fair value	7,547	10,742
Securities unrealized losses	319	333
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available for Sale:
Available for sale securities less than 12 months fair value	3,493	4,619
Available for sale securities less than 12 months unrealized losses	13	8
Available for sale securities 12 months or more fair value		88
Available for sale securities fair value	3,493	4,707
Available for sale securities unrealized losses	13	8
Other Securities [Member]
Available for Sale:
Available for sale securities less than 12 months fair value		165
Available for sale securities less than 12 months unrealized losses		93
Available for sale securities 12 months or more fair value	240	29
Available for sale securities 12 months or more unrealized losses	120	73
Available for sale securities fair value	240	194
Available for sale securities unrealized losses	120	166
Held to Maturity:
Held to maturity securities less than 12 months fair value	896	997
Held to maturity securities less than 12 months unrealized losses	104	3
Held to maturity securities 12 months or more fair value	2,918	2,848
Held to maturity securities 12 months or more unrealized losses	82	152
Held to maturity securities fair value	3,814	3,845
Held to maturity securities unrealized losses	186	155
US Government Agencies Debt Securities [Member]
Held to Maturity:
Held to maturity securities less than 12 months fair value		1,996
Held to maturity securities less than 12 months unrealized losses		4
Held to maturity securities fair value		1,996
Held to maturity securities unrealized losses		$ 4

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