PSB Holdings, Inc. Acquisition of Marathon State Bank (Details1) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Pro Forma with Marathon State Bank
Net Interest Income	$ 5,294	$ 5,163	$ 4,880	$ 4,816	$ 5,060	$ 4,867	$ 4,866	$ 4,764	$ 4,900	$ 5,019	$ 4,795	$ 4,385	$ 20,153	$ 19,557	$ 19,099
Noninterest Income	1,559	1,444	2,323	1,242	1,376	1,367	1,197	1,397	1,512	1,463	1,297	1,091	6,568	5,337	5,363
Net Income	1,685	1,226	1,918	1,180	1,400	1,394	1,226	1,285	1,334	1,331	1,208	881	6,009	5,305	4,754
Earnings Per Share	$ 1.01	$ 0.74	$ 1.15	$ 0.70	$ 0.85	$ 0.85	$ 0.74	$ 0.78	$ 0.81	$ 0.81	$ 0.73	$ 0.53	$ 3.61	$ 3.21	$ 2.89
PSB Holdings, Inc.
Pro Forma with Marathon State Bank
Net Interest Income													19,670	19,557
Noninterest Income													5,706	5,337
Net Income													5,587	5,305
Earnings Per Share													$ 3.36	$ 3.21
Marathon State Bank
Pro Forma with Marathon State Bank
Net Interest Income													1,158	1,782
Noninterest Income													880	44
Net Income													468	571
Earnings Per Share													$ 0.28	$ 0.34
Pro Forma Combined
Pro Forma with Marathon State Bank
Net Interest Income													20,828	21,339
Noninterest Income													6,586	5,381
Net Income													$ 6,055	$ 5,876
Earnings Per Share													$ 3.64	$ 3.55