Loans (Details 8) (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
Number of loans	211	141
Pre-Modification outstanding recorded investment	$ 16,731	$ 30,550
Post-Modification recorded investment	15,745	29,367
Permanent Real Estate Loans [Member]
Loans by class modified as troubled debt restructurings
Number of loans	121	64
Pre-Modification outstanding recorded investment	8,481	15,153
Post-Modification recorded investment	7,436	14,526
Permanent Real Estate Loans [Member] | One-to four-family residential [Member]
Loans by class modified as troubled debt restructurings
Number of loans	114	55
Pre-Modification outstanding recorded investment	6,618	7,344
Post-Modification recorded investment	5,574	7,485
Permanent Real Estate Loans [Member] | Multifamily residential [Member]
Loans by class modified as troubled debt restructurings
Number of loans	6	2
Pre-Modification outstanding recorded investment	1,439	2,246
Post-Modification recorded investment	1,438	2,246
Permanent Real Estate Loans [Member] | Nonresidential [Member]
Loans by class modified as troubled debt restructurings
Number of loans	1	3
Pre-Modification outstanding recorded investment	424	1,271
Post-Modification recorded investment	424	1,271
Permanent Real Estate Loans [Member] | Land [Member]
Loans by class modified as troubled debt restructurings
Number of loans		4
Pre-Modification outstanding recorded investment		4,292
Post-Modification recorded investment		3,524
Construction Loans [Member]
Loans by class modified as troubled debt restructurings
Number of loans	3	19
Pre-Modification outstanding recorded investment	853	4,425
Post-Modification recorded investment	830	3,881
Construction Loans [Member] | One-to four-family residential [Member]
Loans by class modified as troubled debt restructurings
Number of loans	3	19
Pre-Modification outstanding recorded investment	853	4,425
Post-Modification recorded investment	830	3,881
Construction Loans [Member] | Multifamily and nonresidential [Member]
Loans by class modified as troubled debt restructurings
Number of loans
Pre-Modification outstanding recorded investment
Post-Modification recorded investment
Consumer Loans [Member]
Loans by class modified as troubled debt restructurings
Number of loans	86	55
Pre-Modification outstanding recorded investment	6,951	1,868
Post-Modification recorded investment	7,033	1,862
Consumer Loans [Member] | Home Equity [Member]
Loans by class modified as troubled debt restructurings
Number of loans	86	54
Pre-Modification outstanding recorded investment	6,951	1,847
Post-Modification recorded investment	7,033	1,841
Consumer Loans [Member] | Auto [Member]
Loans by class modified as troubled debt restructurings
Number of loans		1
Pre-Modification outstanding recorded investment		21
Post-Modification recorded investment		21
Consumer Loans [Member] | Marine [Member]
Loans by class modified as troubled debt restructurings
Number of loans
Pre-Modification outstanding recorded investment
Post-Modification recorded investment
Consumer Loans [Member] | Recreational vehicles [Member]
Loans by class modified as troubled debt restructurings
Number of loans
Pre-Modification outstanding recorded investment
Post-Modification recorded investment
Consumer Loans [Member] | Other [Member]
Loans by class modified as troubled debt restructurings
Number of loans
Pre-Modification outstanding recorded investment
Post-Modification recorded investment
Commercial Loans [Member]
Loans by class modified as troubled debt restructurings
Number of loans	1	3
Pre-Modification outstanding recorded investment	446	9,104
Post-Modification recorded investment	446	9,098
Commercial Loans [Member] | Secured [Member]
Loans by class modified as troubled debt restructurings
Number of loans		3
Pre-Modification outstanding recorded investment		9,104
Post-Modification recorded investment		9,098
Commercial Loans [Member] | Unsecured [Member]
Loans by class modified as troubled debt restructurings
Number of loans	1
Pre-Modification outstanding recorded investment	446
Post-Modification recorded investment	$ 446