XML 52 R41.htm IDEA: XBRL DOCUMENT
v3.20.2

Stock-Based Compensation - Additional Information (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Oct. 16, 2013 | Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Stock Based Compensation [Abstract] |  |  |  |  |
Stock-Based Compensation expense |  | $ 0 | $ 0 | $ 0 | $ 0
Stock options granted |  |  |  | 0 | 0
Stock options outstanding |  | 0 |  | 0 |
Increase in number of common stock shares authorized | 233,334 |  |  |  |
Percentage to retain annual restricted stock awards | 50.00% |  |  |  |
Stock options exercise price description |  |  |  |  | may not be exercised at a price which is less than 100% of the fair market value of shares at the date of grant
Restricted Stock [Member] |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |
Stock-Based Compensation expense |  | $ 612,000 | 565,000 | $ 1,181,000 | $ 1,124,000
Recognized tax benefits |  | $ 69,000 | $ 62,000 | $ 127,000 | $ 125,000
Class A Common Stock | Stock Option [Member] |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 990,000 |  |  |  |
Class A Common Stock | Convert For Class B [Member] |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 370,000 |  |  |  |
Class A Common Stock | Incentive Compensation Plan [Member] |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 620,000 |  |  |  |
Class B Common Stock |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |
Increase in number of common stock shares authorized | 90,000 |  |  |  |
Class B Common Stock | Stock Option [Member] |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 370,000 |  |  |  |

X
- Definition The percentage to retain annual restricted stock awards. + References No definition available. + Details
Name: | sga_PercentageToRetainAnnualRestrictedStockAwards
Namespace Prefix: | sga_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Describes the stock options exercise price. + References No definition available. + Details
Name: | sga_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisePriceDescription
Namespace Prefix: | sga_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of additional shares authorized for issuance under share-based payment arrangement. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_StockOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=sga_ConvertForClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=sga_IncentiveCompensationPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |