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Long-Term Debt (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 0 Months Ended |  |
--- | --- | --- | ---
Mar. 06, 2013 | Sep. 12, 2012 | Mar. 14, 2012 | Dec. 31, 2012 | Dec. 31, 2011
Maximum [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Interest rate per annum |  |  |  | 8.25% |
Minimum [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Interest rate per annum |  |  |  | 5.50% |
F&M Bank [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Maximum line of credit | $ 40 |  |  | $ 40 |
Borrowing base | 21.5 | 23.0 | 20.0 | 21.5 |
Increased borrowing base |  |  | 23 |  |
Decreased borrowing base | 20.50 | 21.50 |  |  |
Interest rate per annum |  |  |  | 5.25% |
Loans and letters of credit amount outstanding | $ 9.1 |  |  | $ 10.1 | $ 11.5
F&M Bank [Member] | Maximum [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Interest rate per annum | 5.25% |  | 5.25% |  |
F&M Bank [Member] | Minimum [Member] |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |
Rate above prime | 0.25% |  | 0.25% |  |

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- Definition Line Of Credit Facility Decreased Borrowing Base + References No definition available. + Details
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- Definition Line Of Credit Facility Increased Borrowing Base + References No definition available. + Details
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- Definition The percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount borrowed under the credit facility as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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