Loans and Allowance - Corporation's nonaccrual loans (Details 5) (Loans Receivable, USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	$ 11,514	$ 10,850
Nonaccrual loans as a percent of total loans receivable	3.53%	3.45%
Construction/Land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	3,864	4,798
One-to-four family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	3,833	2,687
Multi-family residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	1,073	1,104
Nonresidential and agricultural land
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	2,377	1,678
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	362	567
Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total nonaccrual loans	$ 5	$ 16