Document And Entity Information	6 Months Ended
	Jun. 30, 2012	Aug. 06, 2012
Document And Entity Information [Abstract]
Document Type	10-Q
Document Period End Date	Jun. 30, 2012
Amendment Flag	true
Amendment Description	The sole purpose of this amendment on Form 10-Q/A to Northrim Bancorp, Inc's Quarterly Report on Form 10-Q for the quarter ended June 30, 2012, filed with the Securities and Exchange Commission on August 6, 2012 (the "Form 10-Q") is to furnish a corrected interactive data file formatted in XBRL (Extensible Business Reporting Language) on Exhibit 101 to the Form 10-Q, as required by Rule 405 of Regulation S-T. The corrected Exhibit 101 reflects changes to indicate the correct number of shares of authorized preferred stock and a calendar date correction to the number of outstanding shares of common stock. No other changes have been made to the Form 10-Q. This Form 10-Q/A speaks as of the original filing date of the Form 10-Q, does not reflect events that may have occurred subsequent to the original filing date, and does not modify or update in any way disclosures made in the Form 10-Q. Pursuant to Rule 406T of Regulation S-T, the interactive data files on Exhibit 101 to this Form 10-Q/A are deemed not filed or part of a registration statement or prospectus for purposes of Sections 11 or 12 of the Securities Act of 1933, as amended, are deemed not filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and otherwise are not subject to liability under those sections.
Entity Registrant Name	NORTHRIM BANCORP INC
Entity Central Index Key	0001163370
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Common Stock, Shares Outstanding		6,470,518
Trading Symbol	NRIM