Description of Plan - Notes Receivable from Participants (Details) - Employees' 401(k) Savings and Investment Plan	12 Months Ended
Dec. 31, 2025 USD ($)
Description of Plan
Note receivable, minimum borrowing amount	$ 1,000
Note receivable, maximum borrowing amount	$ 50,000
Note receivable, maximum borrowing percentage	50.00%
Maximum loan term if proceeds are used for the purchase of principal residence	15 years
Basis spread on prime rate (as a percent)	1.00%
Minimum
Description of Plan
Loan term	1 year
Loan interest rate	4.25%
Maximum
Description of Plan
Loan term	5 years
Loan interest rate	9.50%

Represents the percentage points added to the prime rate to compute the interest rate on participant loans.

No definition available.

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Period Type:	duration

- Definition

Represents the maximum term of loan if proceeds are used for the purchase of principal residence.

+ References

No definition available.

+ Details

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- Definition

Term of participant loan of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

No definition available.

+ Details

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Namespace Prefix:	sga_
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- 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

+ Details

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- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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- Details

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- Details

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