Consolidated Statements Of Changes In Shareholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Non-controlling Interest
Beginning balance, value at Dec. 31, 2013	$ 144,318	$ 6,538	$ 54,089	$ 82,855	$ 669	$ 167
Beginning balance, shares at Dec. 31, 2013		6,538,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Acquisition adjustment, shares		290,000
Acquisition adjustment, value	7,446	290	7,156
Cash dividend declared	(4,770)			(4,770)
Stock based compensation expense	360		360
Exercise of stock options, shares		26,000
Exercise of stock options	54	26	28
Excess tax benefits from stock based payment arrangements	96		96
Distributions to noncontrolling interest	(508)					(508)
Other comprehensive income, net of tax	(422)				(422)
Net income attributable to the noncontrolling interest	459					459
Net income attributable to Northrim BanCorp	17,408			17,408
Ending balance, value at Dec. 31, 2014	164,441	6,854	61,729	95,493	247	118
Ending balance, shares at Dec. 31, 2014	6,854,189	6,854,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividend declared	(1,245)			(1,245)
Stock based compensation expense	118		118
Distributions to noncontrolling interest	(63)					(63)
Other comprehensive income, net of tax	500				500
Net income attributable to the noncontrolling interest	72					72
Net income attributable to Northrim BanCorp	3,561			3,561
Ending balance, value at Mar. 31, 2015	$ 167,384	$ 6,854	$ 61,847	$ 97,809	$ 747	$ 127
Ending balance, shares at Mar. 31, 2015	6,854,189	6,854,000