Borrowings Narrative (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Line of Credit Facility [Line Items]
Remaining credit availability	$ 305,500,000
Long-term Debt	55,000,000us-gaap_LongTermDebt
Federal Home Loan Bank advances, Interest rate, range from (in hundredths)	0.20%
Federal Home Loan Bank advances, Interest rate, range to (in hundredths)	1.11%
Federal Home Loan Bank advances, Weighted-average rate (in hundredths)	0.46%	1.13%
Federal Home Loan Bank borrowings	55,000,000	80,000,000
Securities sold under agreements to repurchase, maturing the day following the day sold	26,300,000	22,170,000
Federal Reserve Bank of Richmond [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum credit limit	35,800,000.0
Revolving lines of credit, outstanding balance	0
Other Institutions [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum credit limit	24,000,000
Southern Trust Mortgage [Member] \| Regional Bank [Member] \| Fund Mortgage Held For Sale [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum credit limit		75,000,000
Revolving lines of credit, outstanding balance		32,300,000
Southern Trust Mortgage [Member] \| Subsidiary Bank [Member] \| Fund Mortgage Held For Sale [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum credit limit	17,000,000
Revolving lines of credit, outstanding balance	8,500,000
Southern Trust Mortgage [Member] \| Subsidiary Bank [Member] \| Operating Purpose [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum credit limit		5,000,000
Revolving lines of credit, outstanding balance		89,000
Counterparty One [Member]
Line of Credit Facility [Line Items]
Securities sold under agreements to repurchase, structured repurchase agreements, January 18, 2015	7,200,000	7,400,000
Counterparty Two [Member]
Line of Credit Facility [Line Items]
Securities sold under agreements to repurchase, structured repurchase agreements, January 18, 2015	$ 5,000,000	$ 5,000,000

Securities Sold Under Agreements to Repurchase, Maturing the Day Following the Day Sold

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- Definition

Securities Sold Under Agreements to Repurchase, Structured Repurchase Agreements

+ References

No definition available.

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- Definition

States the lowest interest rate applicable to any of the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

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- Definition

States the highest interest rate applicable to any of the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

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- Definition

States the weighted average interest rate applicable to the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

+ References

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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