Financial Information of Wells Financial Corp. (Parent Only) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assets [Abstract]
Cash	$ 12,059	$ 14,373	$ 12,625
Total assets	274,779	251,826
Liabilities and Stockholders' Equity
Liabilities	243,479	225,207
Redeemable common stock held by ESOP, $0.10 par value, shares issued and outstanding, 91,459 at December 31, 2015; 95,602 at December 31, 2014	2,881	2,533
Stockholders' equity	28,419	24,086	23,741
Total liabilities, mezzanine equity and stockholders' equity	274,779	251,826
Wells Financial Corp. and Subsidiary
Assets [Abstract]
Cash	2,094	740	$ 564
Prepaid fees and other assets	166	218
Investment in Wells Federal Bank	29,060	25,661
Total assets	31,320	26,619
Liabilities and Stockholders' Equity
Liabilities	20
Redeemable common stock held by ESOP, $0.10 par value, shares issued and outstanding, 91,459 at December 31, 2015; 95,602 at December 31, 2014	2,881	2,533
Stockholders' equity	28,419	24,086
Total liabilities, mezzanine equity and stockholders' equity	$ 31,320	$ 26,619