Note 28 - Parent Company Financial Statements - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash	$ 66,970	$ 68,407	$ 51,192	$ 58,422
Investment in Bank of Commerce Holdings Trust II	310	310
Other assets	19,661	20,356
Total assets	1,269,421	1,140,992
Junior subordinated debentures	10,310	10,310
Other liabilities	12,157	13,177
Total liabilities	1,142,157	1,046,886
Total liabilities and shareholders’ equity	1,269,421	1,140,992
Parent Company [Member]
Cash	23,984	493
Redding Bank of Commerce	130,658	122,707
Bank of Commerce Mortgage	(64)	(64)
Investment in Bank of Commerce Holdings Trust II	310	310
Other assets	169	124
Total assets	155,057	123,570
Senior debt, net	7,090	8,904
Subordinated debt, net	9,868	9,829
Junior subordinated debentures	10,310	10,310
Other liabilities	525	421
Total liabilities	27,793	29,464
Shareholders’ equity	127,264	94,106
Total liabilities and shareholders’ equity	$ 155,057	$ 123,570