Mergers and Acquisitions (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition
Bargain purchase gain, amount	$ 680,000	$ 0	$ 0
FNBR Holding Corporation
Business Acquisition
Effective Date of Acquisition	Aug. 31, 2014
Percentage of Outstanding Common Stock Acquired	100.00%
Business Combination, Consideration Transferred	31,817,000
Number of Shares Issued for Aquisition	555,732
Cash consideration for outstanding shares	16,690,000
Bargain purchase gain, amount	680,000
Bargain purchase gain, financial statement caption	The bargain purchase gain is included in other income in the Company’s consolidated statements of operations.
Loans receivable	137,488,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due	146,019,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due, Expected to be Uncollectible	0
Core deposit intangible	4,199,000
Core Deposit Intangible Assets, Weighted Average Useful Life	10 years
Third-party Acquisition Related Costs	552,000
Net interest income and non-interest income	6,672,000
Net income	1,675,000
North Cascades Bancshares
Business Acquisition
Effective Date of Acquisition		Jul. 31, 2013
Percentage of Outstanding Common Stock Acquired		100.00%
Business Combination, Consideration Transferred		30,576,000
Number of Shares Issued for Aquisition		687,876
Cash consideration for outstanding shares		13,833,000
Loans receivable		215,986,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due		223,949,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due, Expected to be Uncollectible		0
Core deposit intangible		3,660,000
Core Deposit Intangible Assets, Weighted Average Useful Life		10 years
Third-party Acquisition Related Costs		667,000
Net interest income and non-interest income		6,837,000
Net income		1,108,000
Wheatland Bankshares
Business Acquisition
Effective Date of Acquisition		May 31, 2013
Percentage of Outstanding Common Stock Acquired		100.00%
Business Combination, Consideration Transferred		39,315,000
Number of Shares Issued for Aquisition		1,455,256
Cash consideration for outstanding shares		11,025,000
Loans receivable		171,199,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due		176,698,000
Loans Receivable Acquired, Gross Principal and Contractual Interest Due, Expected to be Uncollectible		0
Core deposit intangible		2,079,000
Core Deposit Intangible Assets, Weighted Average Useful Life		11 years
Third-party Acquisition Related Costs		832,000
Net interest income and non-interest income		7,946,000
Net income		$ 2,100,000