Loans and Allowance - Information regarding newly restructured troubled debt by type of modification (Details 8) (Loans Receivable, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term	2,564	1,710
Combination	1,829	2,939
Total Modifications	4,393	4,649
Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term	125
Combination
Total Modifications	125
One-to-four family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term	80	1,358
Combination	493
Total Modifications	573	1,358
Multi-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term
Combination	1,051	1,966
Total Modifications	1,051	1,966
Nonresidential real estate and agricultural land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term		329
Combination		956
Total Modifications		1,285
Land not agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term	2,359
Combination
Total Modifications	2,359
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term		23
Combination	285
Total Modifications	285	23
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Only
Term
Combination		17
Total Modifications		$ 17