Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest Income
Interest and fees on loans and loans held for sale	$ 57,542	$ 55,041	$ 54,777
Interest on investment securities available for sale	5,481	4,230	3,580
Dividends on marketable equity securities	348	345	315
Interest on investment securities held to maturity	0	59	41
Interest on deposits in other banks	806	433	205
Total Interest Income	64,177	60,108	58,918
Interest Expense
Interest expense on deposits	2,307	1,707	1,870
Interest expense on securities sold under agreements to repurchase	50	34	30
Interest expense on borrowings	223	173	127
Interest expense on junior subordinated debentures	389	516	534
Total Interest Expense	2,969	2,430	2,561
Net Interest Income	61,208	57,678	56,357
(Benefit) provision for loan losses	(500)	3,200	2,298
Net Interest Income After Provision for Loan Losses	61,708	54,478	54,059
Other Operating Income
Mortgage banking income	20,844	23,287	29,507
Purchased receivable income	3,255	2,975	2,347
Revenue from contract with customer	5,911	5,826	6,280
Commercial servicing revenue	1,422	372	322
Gain on sale of Northrim Benefits Group	0	4,445	0
Employee benefit plan income	0	2,506	3,770
Gain (loss) on sale of securities	0	11	(11)
Loss on marketable equity securities	(625)	0	0
Other income	2,952	2,667	2,660
Total Other Operating Income	32,167	40,474	43,263
Other Operating Expense
Salaries and other personnel expense	44,650	44,721	46,752
Occupancy expense	6,136	6,752	6,462
Data processing expense	6,035	5,549	4,879
Professional and outside services	2,453	2,365	2,797
Marketing expense	2,318	2,566	2,449
Insurance expense	862	1,161	1,023
Impairment of equity method investment	804	686	0
OREO expense, net of rental income and gains on sale	258	837	98
Intangible asset amortization expense	70	100	135
Loss on sale of premises and equipment	2	3	352
Compensation expense - RML acquisition payments	0	130	4,775
Other operating expense	6,212	6,283	6,558
Total Other Operating Expense	69,800	71,153	76,280
Income Before Provision for Income Taxes	24,075	23,799	21,042
Provision for income taxes	4,071	10,321	6,052
Net Income	20,004	13,478	14,990
Less: Net income attributable to the noncontrolling interest	0	327	579
Net Income Attributable to Northrim BanCorp, Inc.	$ 20,004	$ 13,151	$ 14,411
Earnings per share, basic (in USD per share)	$ 2.91	$ 1.91	$ 2.09
Earnings per share, diluted (in USD per share)	$ 2.86	$ 1.88	$ 2.06
Weighted Average Shares Outstanding, Basic (in shares)	6,877,573	6,889,621	6,883,663
Weighted Average Shares Outstanding, Diluted (in shares)	6,981,557	6,977,910	6,974,864
Bankcard fees
Other Operating Income
Revenue from contract with customer	$ 2,811	$ 2,597	$ 2,670
Service charges on deposit accounts
Other Operating Income
Revenue from contract with customer	$ 1,508	$ 1,614	$ 1,998