Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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Fixed interest rate related to the interest rate derivative.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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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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Note 6 - Long-Term Debt (Details) (USD $)	12 Months Ended	1 Months Ended	0 Months Ended
Note 6 - Long-Term Debt (Details) (USD $)	Dec. 31, 2014	Jul. 31, 2013	Jul. 01, 2018	Dec. 31, 2014	Jul. 01, 2013	May 01, 2014	Dec. 31, 2013	Oct. 22, 2013	Oct. 21, 2013
Note 6 - Long-Term Debt (Details) [Line Items]
Letters of Credit Outstanding, Amount	$ 0			0
Derivative, Notional Amount		14,250,000invest_DerivativeNotionalAmount
Debt Issuance Cost	68,000us-gaap_DebtIssuanceCosts
Ratio Of Maximum Funded Indebtedness To EBITDA							4.0
Fixed Charges Numerator	1.25sgc_FixedChargesNumerator			1.25sgc_FixedChargesNumerator
Effective July 1, 2014 [Member] \| Scenario, Forecast [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Derivative, Fixed Interest Rate		2.53%
Per Month Through July 1 2015 [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Periodic Payment, Principal		187,500
Per Month Through June 1 2018 [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Periodic Payment, Principal		250,000
Scenario, Forecast [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Periodic Payment, Principal			3,250,000
Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Fifth Third Bank [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					0.95%
Debt Instrument, Basis Spread on Variable Rate				1.10%
Term Loan [Member] \| Fifth Third Bank [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Face Amount					30,000,000
Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	2,375,000			2,375,000
Long-term Debt, Maturities, Repayments of Principal in Year Two	3,000,000			3,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Three	3,000,000			3,000,000
Long-term Debt, Maturities, Repayments of Principal in Year Four	16,000,000			16,000,000
Senior Debt [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Ratio Of Maximum Funded Indebtedness To EBITDA	3.5			3.5
Interest Rate Swap [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Interest Rate Derivative Assets, at Fair Value	172,000			172,000
Increase (Decrease) in Derivative Assets	172,000
Other Tax Expense (Benefit)	61,000
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Fifth Third Bank [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					0.95%
Debt Instrument, Basis Spread on Variable Rate				1.20%
Revolving Credit Facility [Member] \| Fifth Third Bank [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						10,000,000
Line of Credit Facility, Commitment Fee Percentage					0.10%
Revolving Credit Facility [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					15,000,000
Permitted Investments In Subsidiaries								$ 5,000,000	$ 1,000,000
London Interbank Offered Rate (LIBOR) [Member] \| Fifth Third Bank [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						0.95%
Debt Instrument, Basis Spread on Variable Rate				1.20%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage						0.50%
Fifth Third Bank [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Line of Credit Facility, Expiration Period					5 years