Secured Credit Facility (Details)	6 Months Ended
Jun. 30, 2016 USD ($)	Jun. 18, 2015 USD ($)
Interest Rate Swap [Member]
Secured Credit Facility (Details) [Line Items]
Aggregate Indebtedness		$ 14,000,000
Debt, Weighted Average Interest Rate	4.22%
Secured Debt [Member]
Secured Credit Facility (Details) [Line Items]
Debt Instrument, Covenant Description	Our loan agreements include restrictions on our ability to pay cash dividends to our stockholders. However, we are allowed to pay dividends (a) (i) in an amount up to $2,100,000 in any year if our “Total Leverage Ratio,” that is, the ratio of our “Indebtedness” to “EBITDA” (earnings before interest, taxes, depreciation and amortization – as defined in the loan documents) is greater than 2.50 to 1.00, and (ii) in any amount if our Total Leverage Ratio is less than 2.50 to 1.00, and (b) in either case, if we are not in default or potential default under the loan agreements.
Debt Instrument, Threshold Amount, Dividends	$ 2,100,000
Ratio of Indebtedness to Net Capital	2.30
Debt Instrument, Covenant Compliance	Our credit facility requires us to comply with specified financial ratios and tests. These financial ratios and tests include total leverage ratio, debt service coverage ratio, equity to total assets ratio, fixed coverage ratio and maximum annual capital expenditures tests.
Long-term Line of Credit	$ 20,000,000
Secured Debt [Member] \| Amended And Restated MLA With Co Bank [Member]
Secured Credit Facility (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 35,000,000
Debt Instrument, Average Weighted Life	3 years
Revolving Credit Facility [Member]
Secured Credit Facility (Details) [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 6,000,000
Revolving Credit Facility [Member] \| Amended And Restated MLA With Co Bank [Member]
Secured Credit Facility (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	9,000,000
Line of Credit Facility, Increase, Maximum Borrowing Capacity	6,000,000
Additional Secured Debt [Member] \| Amended And Restated MLA With Co Bank [Member]
Secured Credit Facility (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 6,000,000
Secured Credit Facility [Member]
Secured Credit Facility (Details) [Line Items]
Debt, Weighted Average Interest Rate	3.46%
Line of Credit Facility, Remaining Borrowing Capacity	$ 26,000,000

Average weighted life of the debt amount.

No definition available.

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- Definition

Threshold amount of dividends for debt instrument.

+ References

No definition available.

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- Definition

Increase for additional borrowings on the credit facility during the period.

+ References

No definition available.

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- References

No definition available.

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- Definition

Total current liabilities of the broker-dealer, less certain exceptions as defined.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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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.

+ 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 FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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).

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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