Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual, Adjustment

No definition available.

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- Definition

Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual, Adjustment

+ References

No definition available.

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- Definition

Net Interest and Other Income

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The net amount of operating interest income (expense).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

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No definition available.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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Business Combinations - Pro Forma Information (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended			1 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro Forma Revenue									$ 73,442nrim_NetInterestandOtherIncome	$ 56,920nrim_NetInterestandOtherIncome
Net income attributable to Northrim Bancorp	6,674us-gaap_NetIncomeLoss	3,707us-gaap_NetIncomeLoss	4,369us-gaap_NetIncomeLoss	2,658us-gaap_NetIncomeLoss	2,681us-gaap_NetIncomeLoss	3,474us-gaap_NetIncomeLoss	3,496us-gaap_NetIncomeLoss	2,674us-gaap_NetIncomeLoss	17,408us-gaap_NetIncomeLoss	12,325us-gaap_NetIncomeLoss	12,946us-gaap_NetIncomeLoss
Earnings per share, basic (USD per share)	$ 0.98us-gaap_EarningsPerShareBasic	$ 0.54us-gaap_EarningsPerShareBasic	$ 0.64us-gaap_EarningsPerShareBasic	$ 0.41us-gaap_EarningsPerShareBasic	$ 0.41us-gaap_EarningsPerShareBasic	$ 0.53us-gaap_EarningsPerShareBasic	$ 0.54us-gaap_EarningsPerShareBasic	$ 0.41us-gaap_EarningsPerShareBasic	$ 2.57us-gaap_EarningsPerShareBasic	$ 1.89us-gaap_EarningsPerShareBasic	$ 2.00us-gaap_EarningsPerShareBasic
Earnings per share, diluted (USD per share)	$ 0.97us-gaap_EarningsPerShareDiluted	$ 0.53us-gaap_EarningsPerShareDiluted	$ 0.63us-gaap_EarningsPerShareDiluted	$ 0.40us-gaap_EarningsPerShareDiluted	$ 0.40us-gaap_EarningsPerShareDiluted	$ 0.53us-gaap_EarningsPerShareDiluted	$ 0.53us-gaap_EarningsPerShareDiluted	$ 0.41us-gaap_EarningsPerShareDiluted	$ 2.54us-gaap_EarningsPerShareDiluted	$ 1.87us-gaap_EarningsPerShareDiluted	$ 1.97us-gaap_EarningsPerShareDiluted
Weighted Average Shares Outstanding, Basic (shares)									6,761,328	6,518,772	6,477,266
Weighted Average Shares Outstanding, Diluted (shares)									6,852,267	6,609,950	6,574,993
Net interest income	14,536us-gaap_InterestIncomeExpenseNet	13,725us-gaap_InterestIncomeExpenseNet	13,411us-gaap_InterestIncomeExpenseNet	11,233us-gaap_InterestIncomeExpenseNet	11,521us-gaap_InterestIncomeExpenseNet	11,022us-gaap_InterestIncomeExpenseNet	10,929us-gaap_InterestIncomeExpenseNet	10,562us-gaap_InterestIncomeExpenseNet	52,905us-gaap_InterestIncomeExpenseNet	44,034us-gaap_InterestIncomeExpenseNet	42,223us-gaap_InterestIncomeExpenseNet
Alaska Pacific Bank
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Weighted Average Shares Outstanding, Basic (shares)									6,761,328	6,518,772
Weighted Average Shares Outstanding, Diluted (shares)									6,852,267	6,609,950
Pro Forma, Interest Income		7,500							2,095	9,872
Pro Forma Information, Net Income (Loss) Since Acquisition									(1,282)	329
Pro Forma Information, Revenue Since Acquisition									0	(38)
Pro Forma Information, Net Income (Loss) since Acquisition, Adjustment									(180)	82
Pro Forma Revenue									75,537	66,754
Pro Forma Net Income (Loss)									15,946	12,736
Pro Forma Earnings Per Share, Basic (USD per share)									$ 2.36	$ 1.95
Pro Forma Earnings Per Share, Diluted (USD per share)									$ 2.33	$ 1.93
RML
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Weighted Average Shares Outstanding, Basic (shares)									6,761,328	6,518,772
Weighted Average Shares Outstanding, Diluted (shares)									6,852,267	6,609,950
Pro Forma, Interest Income									22,227	28,507		2,400
Pro Forma Information, Net Income (Loss) Since Acquisition									4,000	4,466
Pro Forma Information, Revenue Since Acquisition									(847)	(1,176)
Pro Forma Information, Net Income (Loss) since Acquisition, Adjustment									(3,545)	2,250
Pro Forma Revenue									94,822	84,251
Pro Forma Net Income (Loss)									17,863	19,041
Pro Forma Earnings Per Share, Basic (USD per share)									$ 2.64	$ 2.92
Pro Forma Earnings Per Share, Diluted (USD per share)									$ 2.61	$ 2.88
Net interest income									5,992	7,827
Other Operating Income (Expense), Net									$ 16,235	$ 20,680