Note 10 - Borrowed Funds (Detail) - Schedule of debt financing and notes payable (USD $) In Thousands	Sep. 30, 2011		Dec. 31, 2010
Senior fixed-rate note (1)	$ 15,000	[1]	$ 15,000	[1]
Subordinated fixed-rate note (2)			11,363	[2]
Total debt financing and notes payable - Parent	$ 15,000		$ 26,363

[1] Senior note, issued by Westamerica Bancorporation, originated in October 2003 and maturing October 31, 2013. Interest of 5.31% per annum is payable semiannually on April 30 and October 31, with original principal payment due at maturity.

[2] Subordinated debt, assumed by Westamerica Bancorporation March 1, 2005, originated February 22, 2001. Par amount $10,000 thousand, interest of 10.2% per annum, payable semiannually. Redeemed August 22, 2011 at a premium of approximately 5 percent of the $10,000 thousand principal amount.