Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 4,062	$ 3,922
Securities available for sale:
Unrealized gains (losses) arising during the period	(1,145)	597
Reclassification of net (gains) losses included in net income (net of tax (benefit) expense) of $0 and $6 for the first quarter of 2018 and 2017, respectively	0	(8)
Derivatives and hedging activities:
Unrealized gains arising during the period	467	0
Income tax benefit (expense) related to unrealized gains and losses	260	(223)
Other comprehensive income (loss), net of tax	(418)	366
Comprehensive income	3,644	4,288
Less: comprehensive income attributable to the noncontrolling interest	0	97
Comprehensive income attributable to Northrim BanCorp, Inc.	$ 3,644	$ 4,191

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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