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Credit Facility (Details) (USD $) |  |  | 6 Months Ended |  |  |  | 6 Months Ended |  | 6 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2013 | Dec. 31, 2012 | Jun. 30, 2013 Revolving Credit Facility | Dec. 31, 2011 Revolving Credit Facility | Dec. 31, 2010 Revolving Credit Facility | Jun. 30, 2013 LIBOR-based Rate Revolving Credit Facility | Jun. 30, 2013 CB Floating Rate Revolving Credit Facility | Jun. 30, 2013 Maximum Revolving Credit Facility | Jun. 30, 2013 Maximum LIBOR-based Rate Revolving Credit Facility loan | Jun. 30, 2013 Minimum Revolving Credit Facility
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Borrowing base amount available |  |  | $ 29,000,000 | $ 30,000,000 | $ 20,000,000 |  |  |  |  |
Maximum borrowing capacity |  |  |  | 50,000,000 |  |  |  |  |  |
Potential increase in borrowing capacity |  |  | 20,000,000 |  |  |  |  |  |  |
Borrowing base, component, % of eligible accounts receivable |  |  | 80.00% |  |  |  |  |  |  |
Borrowing base, component, % of eligible inventory |  |  | 50.00% |  |  |  |  |  |  |
Borrowing base, allowable share of total commitment amount attributable to inventory component |  |  | 50.00% |  |  |  |  |  |  |
Borrowing base, component, % of eligible equipment inventory |  |  | 75.00% |  |  |  |  |  |  |
Reference rate, number of allowable LIBOR-based borrowings outstanding |  |  |  |  |  |  |  |  | 3 |
Variable rate, applicable margin |  |  |  |  |  | 1.50% | 1.25% |  |  |
Weighted average interest rate |  |  | 1.45% |  |  |  |  |  |  |
Minimum commitment coverage ratio allowed |  |  |  |  |  |  |  |  |  | 2.00
Maximum leverage ratio allowed |  |  |  |  |  |  |  | 2.50 |  |
Default trigger, certain defaults of other company indebtedness, amount |  |  |  |  |  |  |  | 50,000 |  |
Default trigger, rendering of certain judgments, amount |  |  |  |  |  |  |  | 150,000 |  |
Line of credit, non-current portion | $ 847,000 | $ 897,000 |  |  |  |  |  |  |  |

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- Definition Line of Credit Facility, Minimum Commitment Coverage Ratio Allowed + References No definition available. + Details
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- Definition Line of Credit Facility, Current Borrowing Capacity, Allowable Share of Total Commitment Amount Attributable to General Inventory Component + References No definition available. + Details
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- Definition Line of Credit Facility, Current Borrowing Capacity, Component, Percentage of Eligible Accounts Receivable + References No definition available. + Details
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- Definition Line of Credit Facility, Current Borrowing Capacity, Component, Percentage of Eligible Equipment Inventory + References No definition available. + Details
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- Definition Line of Credit Facility, Current Borrowing Capacity, Component, Percentage of Eligible General Inventory + References No definition available. + Details
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- Definition Line of Credit Facility, Default Trigger, Certain Defaults of Other Company Indebtedness, Amount + References No definition available. + Details
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- Definition Line of Credit Facility, Default Trigger, Rendering of Certain Judgments, Amount + References No definition available. + Details
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- Definition Line of Credit Facility, Maximum Leverage Ratio Allowed + References No definition available. + Details
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- Definition Line of Credit Facility, Potential Increase in Borrowing Capacity + References No definition available. + Details
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- Definition Line of Credit Facility, Reference Rate, Number of Allowable Borrowings Outstanding (e.g. LIBOR Rate, CB Floating Rate, etc.) + 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 Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: 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 2: 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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- Definition The effective interest rate during the reporting period. + References Reference 1: 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 2: 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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- Definition The carrying value as of the balance sheet date of the noncurrent portion 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. + References Reference 1: 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) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Line-of-Credit Arrangement -URI http://asc.fasb.org/extlink&oid=6517033 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6743817&loc=d3e1314-112600 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=6743817&loc=d3e1336-112600 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 6 -Paragraph 9, 10, 11 -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. + Details
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