Debt Instrument, Base Rate, Floor

No definition available.

Name:	sbgi_DebtInstrumentBaseRateFloor
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Covenant, Letters Of Credit Outstanding, Maximum

+ References

No definition available.

+ Details

Name:	sbgi_DebtInstrumentCovenantLettersOfCreditOutstandingMaximum
Namespace Prefix:	sbgi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Cash First Lien Indebtedness Ratio, Threshold In Which Commitment Fee Is Incurred

+ References

No definition available.

+ Details

Name:	sbgi_UnrestrictedCashFirstLienIndebtednessRatioThresholdInWhichCommitmentFeeIsIncurred
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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

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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
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Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
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Period Type:	duration

NOTES PAYABLE AND COMMERCIAL BANK FINANCING - Stated and Weighted Average Effective Interest Rates (Details) - USD ($)		12 Months Ended
	Aug. 23, 2019	Dec. 31, 2020	Dec. 04, 2020	Nov. 01, 2020	Jun. 30, 2020	Dec. 31, 2019	Nov. 27, 2019	Aug. 02, 2019
A/R Facility
Debt Instrument [Line Items]
Interest rate				5.47%
Line of credit \| A/R Facility
Debt Instrument [Line Items]
Aggregate borrowings outstanding		$ 177,000,000
Aggregate outstanding principal amount of loans (less than)		$ 125,000,000
Line of credit \| A/R Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		4.97%
Interest rate floor		0.00%
Notes \| 5.625% Senior Unsecured Notes due 2024
Debt Instrument [Line Items]
Interest rate		5.625%
Weighted average effective interest rate (as a percent)		5.83%				5.83%
Notes \| 5.875% Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Interest rate		5.875%
Weighted average effective interest rate (as a percent)		6.09%				6.09%
Notes \| 5.125% Senior Unsecured Notes due 2027
Debt Instrument [Line Items]
Interest rate		5.125%
Weighted average effective interest rate (as a percent)		5.33%				5.33%
Notes \| 5.500% Unsecured Notes due 2030
Debt Instrument [Line Items]
Interest rate		5.50%					5.50%
Weighted average effective interest rate (as a percent)		5.66%				5.66%
Notes \| 5.375% Secured Notes due 2026
Debt Instrument [Line Items]
Interest rate		5.375%						5.375%
Weighted average effective interest rate (as a percent)		5.73%				5.73%
Notes \| 6.625% Unsecured Notes due 2027
Debt Instrument [Line Items]
Interest rate		6.625%			6.625%
Weighted average effective interest rate (as a percent)		7.00%				7.00%
Notes \| 12.750% Senior Secured Notes, due 2026
Debt Instrument [Line Items]
Interest rate		12.75%
Weighted average effective interest rate (as a percent)		11.95%				0.00%
Notes \| 4.125% Senior Secured Notes due 2030
Debt Instrument [Line Items]
Interest rate		4.125%	4.125%
Weighted average effective interest rate (as a percent)		4.31%				0.00%
STG Term Loan Facility \| Term Loan \| Term Loan B-1
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)		2.94%				4.62%
STG Term Loan Facility \| Term Loan \| Term Loan B-1 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%
STG Term Loan Facility \| Term Loan \| Term Loan B-2
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)		3.29%				4.36%
STG Term Loan Facility \| Term Loan \| Term Loan B-2 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.50%
STG Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
STG Revolving Credit Facility \| Line of credit
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)		0.00%				0.00%
Aggregate borrowings outstanding		$ 0
Letters of credit outstanding		1,000,000
Amount available under facility		$ 649,000,000
STG Revolving Credit Facility \| Line of credit \| Minimum
Debt Instrument [Line Items]
Undrawn commitments fees		0.25%
Unrestricted cash first lien indebtedness ratio		2.75
STG Revolving Credit Facility \| Line of credit \| Weighted Average
Debt Instrument [Line Items]
Undrawn commitments fees		0.375%
STG Revolving Credit Facility \| Line of credit \| Maximum
Debt Instrument [Line Items]
Undrawn commitments fees		0.50%
Unrestricted cash first lien indebtedness ratio		3.0
STG Revolving Credit Facility \| Line of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.00%
DSG Term Loan \| Term Loan
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)		4.21%				5.31%
DSG Term Loan \| Term Loan \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		3.25%
DSG Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
DSG Revolving Credit Facility \| Line of credit
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)		0.00%				0.00%
Aggregate borrowings outstanding		$ 0
Amount available under facility		$ 650,000,000
DSG Revolving Credit Facility \| Line of credit \| Minimum
Debt Instrument [Line Items]
Undrawn commitments fees		0.25%
Unrestricted cash first lien indebtedness ratio		3.25
DSG Revolving Credit Facility \| Line of credit \| Weighted Average
Debt Instrument [Line Items]
Undrawn commitments fees		0.375%
DSG Revolving Credit Facility \| Line of credit \| Maximum
Debt Instrument [Line Items]
Undrawn commitments fees		0.50%
Unrestricted cash first lien indebtedness ratio		3.75
DSG Revolving Credit Facility \| Line of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		3.00%
DSG Accounts Receivable Securitization Facility \| Line of credit
Debt Instrument [Line Items]
Weighted average effective interest rate (as a percent)		4.77%				0.00%
DSG Accounts Receivable Securitization Facility \| Line of credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		4.97%