BANNER CORPORATION AND SUBSIDIARIES - CONSOLIDATED STATEMENTS OF FINANCIAL CONDITION (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
ASSETS
Securities-trading, amortized cost	$ 112,663	$ 128,070
Securities-available-for-sale, amortized cost	462,579	199,058
Securities-held-to-maturity, fair value	$ 80,107	$ 73,916
STOCKHOLDERS' EQUITY
Preferred stock par value per share	$ 0.01	$ 0.01
Preferred stock number of shares authorized	500,000	500,000
Preferred stock Series A liquidation preference per share	$ 1,000	$ 1,000
Preferred stock Series A number of shares issued	124,000	124,000
Preferred stock Series A number of shares outstanding	124,000	124,000
Common stock par value per share	$ 0.01	$ 0.01
Common stock number of shares authorized	50,000,000	50,000,000
Common stock number of shares issued	17,553,472	17,553,472
Common stock number of shares outstanding	17,519,132	16,130,440
Common stock number of shares issued to ESOP trust	34,340	34,340