Loans (Details 9) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Loans	Dec. 31, 2011 Loans
Loans by class modified as troubled debt restructurings with payment default
Number of loans	11	68
Recorded Investment	$ 928	$ 20,796
Permanent Real Estate Loans [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans	9	57
Recorded Investment	851	17,217
Permanent Real Estate Loans [Member] | One-to four-family residential [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans	9	44
Recorded Investment	851	4,893
Permanent Real Estate Loans [Member] | Multifamily residential [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		3
Recorded Investment		3,273
Permanent Real Estate Loans [Member] | Nonresidential [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		5
Recorded Investment		7,278
Permanent Real Estate Loans [Member] | Land [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		5
Recorded Investment		1,773
Construction Loans [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		7
Recorded Investment		799
Construction Loans [Member] | One-to four-family residential [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		7
Recorded Investment		799
Construction Loans [Member] | Multifamily and nonresidential [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans
Recorded Investment
Consumer Loans [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans	2	2
Recorded Investment	77	98
Consumer Loans [Member] | Home Equity [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans	2	1
Recorded Investment	77	94
Consumer Loans [Member] | Auto [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		1
Recorded Investment		4
Consumer Loans [Member] | Marine [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans
Recorded Investment
Consumer Loans [Member] | Recreational vehicles [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans
Recorded Investment
Consumer Loans [Member] | Other [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans
Recorded Investment
Commercial Loans [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		2
Recorded Investment		2,682
Commercial Loans [Member] | Secured [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans		2
Recorded Investment		2,682
Commercial Loans [Member] | Unsecured [Member]
Loans by class modified as troubled debt restructurings with payment default
Number of loans
Recorded Investment