Parent Company Information - Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash and cash equivalents	$ 85,591	$ 141,313	$ 79,530	$ 66,033
Investment securities available for sale	248,688	203,918
Other assets	40,666	34,889
Total assets	1,215,006	1,160,107
Junior subordinated debentures	18,558	18,558
Other liabilities	20,737	11,550
Total liabilities	1,070,688	1,023,754
Common stock	6,538	6,512
Additional paid-in capital	54,089	53,638
Retained earnings	82,855	74,742
Accumulated other comprehensive income	669	1,368
Total Northrim BanCorp shareholders' equity	144,151	136,260
Total liabilities and shareholders' equity	1,215,006	1,160,107
Northrim Bancorp, Inc.
Cash and cash equivalents	10,121	8,749	7,304	5,752
Investment securities available for sale	3,034	3,757
Due from NISC	341	414
Other assets	2,354	913
Total assets	162,709	154,818
Junior subordinated debentures	18,558	18,558
Other liabilities	0	0
Total liabilities	18,558	18,558
Common stock	6,538	6,512
Additional paid-in capital	54,089	53,638
Retained earnings	82,855	74,742
Accumulated other comprehensive income	669	1,368
Total Northrim BanCorp shareholders' equity	144,151	136,260
Total liabilities and shareholders' equity	162,709	154,818
Northrim Bank | Northrim Bancorp, Inc.
Investment in subsidiary	144,799	138,936
Northrim Investment Services Company | Northrim Bancorp, Inc.
Investment in subsidiary	1,502	1,491
Northrim Capital Trust 1 | Northrim Bancorp, Inc.
Investment in subsidiary	248	248
Northrim Statutory Trust 2 | Northrim Bancorp, Inc.
Investment in subsidiary	$ 310	$ 310