Note 7 - Investment Securities (Details) - Amortized Cost and Estimated Fair Value of Securities Held-to-Maturity by Contractual Maturityaturity a (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Amortized Cost and Estimated Fair Value of Securities Held-to-Maturity by Contractual Maturityaturity a [Abstract]
Due in one year or less	$ 0
Due in one year or less	0
Due after one year through five years	163
Due after one year through five years	146
Due after five years through ten years	0
Due after five years through ten years	0
Due after ten years	0
Due after ten years	0
Total investment securities held-to-maturity	163	166
Total investment securities held-to-maturity	$ 146	$ 146