RECENT DEVELOPMENTS AND SIGNIFICANT EVENTS	9 Months Ended
Sep. 30, 2013
Recent Developments and Significant Events [Abstract]
RECENT DEVELOPMENTS AND SIGNIFICANT EVENTS	RECENT DEVELOPMENTS AND SIGNIFICANT EVENTS Proposed Acquisition of Home Federal Bancorp, Inc. On September 24, 2013, Banner and Home Federal Bancorp, Inc. (NASDAQ: HOME), announced the signing of a definitive Agreement and Plan of Merger. The Agreement allowed a thirty-day period during which the board of directors of Home Federal could evaluate purchase offers from other institutions. On October 16, 2013, Home Federal's board declared that it had received a superior proposal from Cascade Bancorp. Under the terms of the Agreement, Banner's board of directors had the right but elected not to match Cascade's offer. Consequently, on October 23, 2013, Banner announced that the Agreement between it and Home Federal had been terminated. In connection with the termination of the Agreement, Home Federal paid a termination fee of $2.95 million to Banner. Income Tax Reporting and Accounting: Amended Federal Income Tax Returns: The Company has years 2010-2012 open for tax examination under the statute of limitation provisions of the Internal Revenue Code of 1986 (Code). Tax years 2006-2009 are not open for assessment of additional tax, but remain open for adjustment to the amount of Net Operating Losses (NOLs), credit, and other carryforwards utilized in open years or to be utilized in the future. The Company filed amended federal income tax returns for tax years 2008 and 2009 to claim additional bad debt deductions, which resulted in additional NOLs for tax years 2008 and 2009. The Company also filed amended federal income tax returns for tax years 2005-2006 and a tentative refund claim for tax year 2007 to carryback the NOLs and general business credits from 2008 and 2009 to those earlier years. Review of the amended returns for all years was completed by the Internal Revenue Service (IRS) in the three months ended September 30, 2013. The Company signed a closing agreement with the IRS related to refund claims of $9.8 million, primarily all related to tax year 2006. Due to the uncertainty of the outcome, the Company had neither previously recorded a receivable nor adjusted deferred tax assets for the amendment. During the three months ended September 30, 2013, the Company recorded a tax receivable of $9.8 million with an offsetting adjustment to its deferred tax assets. Additionally, the Company received interest on the tax receivable of $450,000 in the quarter ending September 30, 2013, which is recorded in miscellaneous income. The Company will further analyze the impact of the closing agreement on subsequent tax years as well as the state income tax impact and record the necessary adjustments at year-end which are not expected to have a material effect on the Company's financial condition or results of operations. Deferred Tax Asset Valuation Allowance: The Company and its wholly-owned subsidiaries file consolidated U.S. federal income tax returns, as well as state income tax returns in Oregon and Idaho. Income taxes are accounted for using the asset and liability method. Under this method a deferred tax asset or liability is determined based on the enacted tax rates which are expected to be in effect when the differences between the financial statement carrying amounts and tax basis of existing assets and liabilities are expected to be reported in the Company’s income tax returns. The effect on deferred taxes of a change in tax rates is recognized in income in the period that includes the enactment date. Under GAAP, a valuation allowance is required to be recognized if it is “more likely than not” that all or a portion of Banner’s deferred tax assets will not be realized. During the quarter ended September 30, 2010, the Company evaluated its net deferred tax asset and determined it was prudent to establish a full valuation allowance against the net asset. At each subsequent quarter-end, the Company ``re-analyzed that position and the Company continued to maintain a full valuation allowance through March 31, 2012. During the quarter ended June 30, 2012, management analyzed the Company’s performance and trends over the previous five quarters, focusing on trends in asset quality, loan loss provisioning, capital position, net interest margin, core operating income and net income and the likelihood of continued profitability. Based on this analysis, management determined that a full valuation allowance was no longer appropriate and reversed nearly all of the valuation allowance at that time. The Company utilized the remaining valuation allowance to offset tax expense in the third and fourth quarters of 2012. The ultimate realization of deferred tax assets is dependent upon the existence, or generation, of taxable income in the periods when those temporary differences and net operating loss and credit carryforwards are deductible. See Note 12 of the Selected Notes to the Consolidated Financial Statements for more information. Preferred Stock Transactions: On March 29, 2012, the Company’s $124 million of senior preferred stock with a liquidation value of $1,000 per share, originally issued to the U.S. Treasury as part of its Capital Purchase Program, was sold by the Treasury as part of its efforts to manage and recover its investments under the Troubled Asset Relief Program (TARP). While the sale of these preferred shares to new owners did not result in any proceeds to the Company and did not change the Company’s capital position or accounting for these securities, it did eliminate restrictions put in place by the Treasury on TARP recipients. During the year ended December 31, 2012, the Company repurchased or redeemed all of its Series A Preferred Stock. The related warrants to purchase up to $18.6 million in Banner common stock (243,998 shares) were sold by the Treasury at public auction in June 2013. That sale did not change the Company's capital position and did not have any impact on the financial accounting and reporting for these securities.

RECENT DEVELOPMENTS AND SIGNIFICANT EVENTS

Proposed Acquisition of Home Federal Bancorp, Inc.

On September 24, 2013, Banner and Home Federal Bancorp, Inc. (NASDAQ: HOME), announced the signing of a definitive Agreement and Plan of Merger. The Agreement allowed a thirty-day period during which the board of directors of Home Federal could evaluate purchase offers from other institutions. On October 16, 2013, Home Federal's board declared that it had received a superior proposal from Cascade Bancorp. Under the terms of the Agreement, Banner's board of directors had the right but elected not to match Cascade's offer. Consequently, on October 23, 2013, Banner announced that the Agreement between it and Home Federal had been terminated. In connection with the termination of the Agreement, Home Federal paid a termination fee of $2.95 million to Banner.

Income Tax Reporting and Accounting:

Amended Federal Income Tax Returns: The Company has years 2010-2012 open for tax examination under the statute of limitation provisions of the Internal Revenue Code of 1986 (Code). Tax years 2006-2009 are not open for assessment of additional tax, but remain open for adjustment to the amount of Net Operating Losses (NOLs), credit, and other carryforwards utilized in open years or to be utilized in the future. The Company filed amended federal income tax returns for tax years 2008 and 2009 to claim additional bad debt deductions, which resulted in additional NOLs for tax years 2008 and 2009. The Company also filed amended federal income tax returns for tax years 2005-2006 and a tentative refund claim for tax year 2007 to carryback the NOLs and general business credits from 2008 and 2009 to those earlier years. Review of the amended returns for all years was completed by the Internal Revenue Service (IRS) in the three months ended September 30, 2013. The Company signed a closing agreement with the IRS related to refund claims of $9.8 million, primarily all related to tax year 2006. Due to the uncertainty of the outcome, the Company had neither previously recorded a receivable nor adjusted deferred tax assets for the amendment. During the three months ended September 30, 2013, the Company recorded a tax receivable of $9.8 million with an offsetting adjustment to its deferred tax assets. Additionally, the Company received interest on the tax receivable of $450,000 in the quarter ending September 30, 2013, which is recorded in miscellaneous income. The Company will further analyze the impact of the closing agreement on subsequent tax years as well as the state income tax impact and record the necessary adjustments at year-end which are not expected to have a material effect on the Company's financial condition or results of operations.

Deferred Tax Asset Valuation Allowance: The Company and its wholly-owned subsidiaries file consolidated U.S. federal income tax returns, as well as state income tax returns in Oregon and Idaho. Income taxes are accounted for using the asset and liability method. Under this method a deferred tax asset or liability is determined based on the enacted tax rates which are expected to be in effect when the differences between the financial statement carrying amounts and tax basis of existing assets and liabilities are expected to be reported in the Company’s income tax returns. The effect on deferred taxes of a change in tax rates is recognized in income in the period that includes the enactment date. Under GAAP, a valuation allowance is required to be recognized if it is “more likely than not” that all or a portion of Banner’s deferred tax assets will not be realized. During the quarter ended September 30, 2010, the Company evaluated its net deferred tax asset and determined it was prudent to establish a full valuation allowance against the net asset. At each subsequent quarter-end, the Company ``re-analyzed that position and the Company continued to maintain a full valuation allowance through March 31, 2012. During the quarter ended June 30, 2012, management analyzed the Company’s performance and trends over the previous five quarters, focusing on trends in asset quality, loan loss provisioning, capital position, net interest margin, core operating income and net income and the likelihood of continued profitability. Based on this analysis, management determined that a full valuation allowance was no longer appropriate and reversed nearly all of the valuation allowance at that time. The Company utilized the remaining valuation allowance to offset tax expense in the third and fourth quarters of 2012. The ultimate realization of deferred tax assets is dependent upon the existence, or generation, of taxable income in the periods when those temporary differences and net operating loss and credit carryforwards are deductible. See Note 12 of the Selected Notes to the Consolidated Financial Statements for more information.

Preferred Stock Transactions:

On March 29, 2012, the Company’s $124 million of senior preferred stock with a liquidation value of $1,000 per share, originally issued to the U.S. Treasury as part of its Capital Purchase Program, was sold by the Treasury as part of its efforts to manage and recover its investments under the Troubled Asset Relief Program (TARP). While the sale of these preferred shares to new owners did not result in any proceeds to the Company and did not change the Company’s capital position or accounting for these securities, it did eliminate restrictions put in place by the Treasury on TARP recipients. During the year ended December 31, 2012, the Company repurchased or redeemed all of its Series A Preferred Stock. The related warrants to purchase up to $18.6 million in Banner common stock (243,998 shares) were sold by the Treasury at public auction in June 2013. That sale did not change the Company's capital position and did not have any impact on the financial accounting and reporting for these securities.