Credit facility participation fee and fronting fee percentage.

No definition available.

Name:	sga_CreditFacilityParticipationFeeAndFrontingFeePercentage
Namespace Prefix:	sga_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

+ Details

Name:	us-gaap_UnamortizedDebtIssuanceExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Long-Term Debt (Narrative) (Details) - USD ($)		3 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Dec. 19, 2022	Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term Debt		$ 0	$ 0
Credit Facility Participation Fee And Fronting Fee Percentage		0.25%
Unamortized Debt Issuance Expense		$ 266,000
Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.25%
Line of Credit Facility, Remaining Borrowing Capacity		$ 50,000,000
Revolving Credit Facility \| SOFR
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end		4.87%
Minimum \| Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.00%
Minimum \| SOFR
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.00%
Minimum \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage		0.20%
Maximum \| Base Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.00%
Maximum \| SOFR
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.00%
Maximum \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage		0.30%
Second Amendment \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ 120,000
Revolving Credit Facility \| Third Amendment
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ 161,000