Loans and Allowance - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of troubled debt restructured loans	9	11
Real estate loans - Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential real estate loans held for sale	$ 14,531	$ 14,531	$ 22,300
Percentage of troubled debt restructured loans	50.00%	38.00%

The aggregate carrying amount of loans receivable that will be sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or elected fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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