Fair Value Inputs, Discount Rate, Basis Spread on Variable Rate Basis

No definition available.

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- Definition

Fair Value Inputs, Discount Rate, Description of Variable Rate Basis

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Details

Name:	us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems
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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=banr_JuniorSubordinatedDebenturesWithVariableInterestRatesWhichResetQuarterlyMember
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FAIR VALUE ACCOUNTING AND MEASUREMENT (Liability Inputs) (Details) (Junior Subordinated Debt [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Fair Value Loss on Instruments	$ 366	$ 207
Discounted cash flows [Member] \| Level 3 [Member]
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Discount Rate, Description of Variable Rate Basis	three-month LIBOR		three-month LIBOR
Discount Rate, Basis Spread on Variable Rate Basis	5.00%		5.25%
Fair Value Loss on Instruments	$ 366
Junior Subordinated Debentures with Variable Interest Rates Which Reset Quarterly [Member] \| Discounted cash flows [Member] \| Level 3 [Member]
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Debt Instrument, Description of Variable Rate Basis	three-month LIBOR
Junior Subordinated Debentures with Variable Interest Rates Which Reset Quarterly [Member] \| Minimum [Member] \| Discounted cash flows [Member] \| Level 3 [Member]
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.38%
Junior Subordinated Debentures with Variable Interest Rates Which Reset Quarterly [Member] \| Maximum [Member] \| Discounted cash flows [Member] \| Level 3 [Member]
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.35%