Consolidated Statements Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 17,867us-gaap_ProfitLoss	$ 12,412us-gaap_ProfitLoss	$ 13,458us-gaap_ProfitLoss
Other comprehensive income, net of tax:
Unrealized gains (losses) arising during the period	(237)	(1,204)	1,843
Reclassification of net gains included in net income (net of tax expense $190, $137, and $138 in 2014, 2013 and 2012, respectively)	(271)	(196)	(198)
Income tax benefit (expense) related to unrealized (losses) gains	86	701	(560)
Other comprehensive income (loss), net of tax	(422)	(699)	1,085
Comprehensive income	17,445	11,713	14,543
Less: comprehensive income attributable to the noncontrolling interest	459	87	512
Comprehensive income attributable to Northrim BanCorp	$ 16,986us-gaap_ComprehensiveIncomeNetOfTax	$ 11,626us-gaap_ComprehensiveIncomeNetOfTax	$ 14,031us-gaap_ComprehensiveIncomeNetOfTax

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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