Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Non-controlling Interest
Beginning balance (in shares) at Dec. 31, 2014		6,854,000
Beginning balance, value at Dec. 31, 2014	$ 164,441	$ 6,854	$ 61,729	$ 95,493	$ 247	$ 118
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividend declared	(5,126)			(5,126)
Stock based compensation expense	608		608
Exercise of stock options (in shares)		23,000
Exercise of stock options	50	$ 23	27
Excess tax benefits from stock based payment arrangements	56		56
Distributions to noncontrolling interest	(490)					(490)
Other comprehensive income, net of tax	(659)				(659)
Net income attributable to the noncontrolling interest	551					551
Net income attributable to Northrim BanCorp, Inc.	17,783			17,783
Ending balance, value at Dec. 31, 2015	$ 177,214	$ 6,877	62,420	108,150	(412)	179
Ending balance (in shares) at Dec. 31, 2015	6,877,140	6,877,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividend declared	$ (1,317)			(1,317)
Stock based compensation expense	$ 161		161
Exercise of stock options (in shares)	0
Distributions to noncontrolling interest	$ (36)					(36)
Other comprehensive income, net of tax	870				870
Net income attributable to the noncontrolling interest	130					130
Net income attributable to Northrim BanCorp, Inc.	3,376			3,376
Ending balance, value at Mar. 31, 2016	$ 180,398	$ 6,877	$ 62,581	$ 110,209	$ 458	$ 273
Ending balance (in shares) at Mar. 31, 2016	6,877,140	6,877,000