PSB Holdings, Inc. Acquisition of Marathon State Bank (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash purchase price	$ 5,505
Cash and due from banks	20,332	14,805
Loans receivable	477,991	437,557
Premises and equipment, net	10,240	9,928
Total fair value of assets acquired	107,000
Non-interest-bearing	89,819	75,298
Interest-bearing	475,623	406,211
Accrued expenses and other liabilities	6,493	6,449
Gain on bargain purchase	851
Marathon State Bank
Accounting date	Jun. 01, 2012
Cash purchase price	5,505
Cash and due from banks	20,392
Securities	50,547
Loans receivable	23,760
Short-term commercial paper and bankers' acceptances	11,713
Foreclosed assets
Premises and equipment, net	402
Core deposit intangible asset
Accrued interest receivable and other assets	550
Total fair value of assets acquired	107,364
Non-interest-bearing	23,255
Interest-bearing	77,611
Accrued expenses and other liabilities	142
Total fair value of liabilities assumed	101,008
Fair value of net assets acquired	6,356
Gain on bargain purchase	$ 851