Note 4 - Loans - Secured Loans Distributed within California (Detail) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 83,385	$ 62,740	$ 46,721	$ 71,017
Loans - percent		100.00%	100.00%
Contra Costa [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 16,724	$ 14,327
Loans - percent		20.10%	22.80%
San Mateo [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 11,099	$ 8,008
Loans - percent		13.30%	12.80%
Santa Clara [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 8,289	$ 4,924
Loans - percent		9.90%	7.90%
San Francisco [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 7,204	$ 7,656
Loans - percent		8.60%	12.20%
Solano [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 1,875	$ 2,575
Loans - percent		2.30%	4.10%
Alameda [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 3,704	$ 920
Loans - percent		4.40%	1.50%
Napa [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 963	$ 976
Loans - percent		1.20%	1.60%
Marin [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 849	$ 674
Loans - percent		1.00%	1.10%
San Francisco Bay Area [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)	[1]	$ 50,707	$ 40,060
Loans - percent	[1]	60.80%	64.00%
El Dorado [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 2,044	$ 2,045
Loans - percent		2.50%	3.20%
Monterey [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 3,513	$ 1,366
Loans - percent		4.20%	3.20%
Santa Cruz [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 871	$ 928
Loans - percent		1.00%	1.50%
Sacramento [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 419	$ 421
Loans - percent		0.50%	0.60%
Calaveras [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 152	$ 156
Loans - percent		0.20%	0.20%
San Benito [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 94	$ 95
Loans - percent		0.10%	0.10%
Mariposa [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 49
Loans - percent		0.10%
Other Northern California [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 7,142	$ 5,011
Loans - percent		8.60%	7.80%
Northern California [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 57,849	$ 45,071
Loans - percent		69.40%	71.80%
Los Angeles [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 22,466	$ 14,873
Loans - percent		26.90%	23.70%
Orange [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 666	$ 669
Loans - percent		0.80%	1.10%
San Diego [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 2,300	$ 375
Loans - percent		2.80%	0.60%
Ventura [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)			$ 344
Loans - percent			0.50%
Los Angeles And Coastal [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 25,432	$ 16,261
Loans - percent		30.50%	25.90%
Kern [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 104	$ 108
Loans - percent		0.10%	0.20%
San Bernardino [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)			$ 1,300
Loans - percent			2.10%
Other Southern California [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 104	$ 1,408
Loans - percent		0.10%	2.30%
Southern California [Member]
Loans Details - Secured Loans by Property Type of the Collateral [Line Items]
Loans - principal (in Dollars)		$ 25,536	$ 17,669
Loans - percent		30.60%	28.20%

[1] Includes the Silicon Valley