Amount of gain (loss) on settlement of insurance claim.

No definition available.

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Namespace Prefix:	sga_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

+ Details

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21B
-URI http://asc.fasb.org/extlink&oid=118932676&loc=SL94080549-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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Other Income (Narrative) (Details) - USD ($)	3 Months Ended	6 Months Ended	12 Months Ended
Other Income (Narrative) (Details) - USD ($)	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2020
Other Income [Line Items]
Proceeds from sale of land and buildings	$ 1,700,000
Gain on sale of land and buildings		$ 1,400,000
Cash proceeds from insurance settlement			$ 233,000
Tower in Keene New Hampshire [Member]
Other Income [Line Items]
Gain on insurance settlement	208,000
Cash proceeds from insurance settlement	$ 208,000