FAIR VALUE MEASUREMENTS: (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
9.25% Senior Secured Second Lien Notes due 2017
FAIR VALUE MEASUREMENTS:
Interest rate (as a percent)	9.25%
8.375% Senior Notes due 2018
FAIR VALUE MEASUREMENTS:
Interest rate (as a percent)	8.375%
6.125% Senior Unsecured Notes due 2022
FAIR VALUE MEASUREMENTS:
Interest rate (as a percent)	6.125%
4.875% Notes
FAIR VALUE MEASUREMENTS:
Interest rate (as a percent)	4.875%
3.0% Convertible Senior Notes, due 2027
FAIR VALUE MEASUREMENTS:
Interest rate (as a percent)	3.00%
Level 1 \| Fair Value \| Cunningham Broadcasting Corporation [Member]
FAIR VALUE MEASUREMENTS:
Number of VIEs who classify investments as trading securities	1
Fair value of trading securities	$ 7,600,000	$ 6,400,000
Level 2 \| Carrying Value \| 9.25% Senior Secured Second Lien Notes due 2017
FAIR VALUE MEASUREMENTS:
Fair Value	490,900,000	490,517,000
Level 2 \| Carrying Value \| 8.375% Senior Notes due 2018
FAIR VALUE MEASUREMENTS:
Fair Value	234,942,000	234,853,000
Level 2 \| Carrying Value \| 6.125% Senior Unsecured Notes due 2022
FAIR VALUE MEASUREMENTS:
Fair Value	500,000,000	500,000,000
Level 2 \| Carrying Value \| Term Loan A
FAIR VALUE MEASUREMENTS:
Fair Value	258,047,000	263,875,000
Level 2 \| Carrying Value \| Term Loan B
FAIR VALUE MEASUREMENTS:
Fair Value	579,509,000	580,850,000
Level 2 \| Carrying Value \| Deerfield Bank Credit Facility
FAIR VALUE MEASUREMENTS:
Fair Value	25,301,000	19,950,000
Level 2 \| Fair Value \| 9.25% Senior Secured Second Lien Notes due 2017
FAIR VALUE MEASUREMENTS:
Fair Value	543,125,000	552,500,000
Level 2 \| Fair Value \| 8.375% Senior Notes due 2018
FAIR VALUE MEASUREMENTS:
Fair Value	265,440,000	265,886,000
Level 2 \| Fair Value \| 6.125% Senior Unsecured Notes due 2022
FAIR VALUE MEASUREMENTS:
Fair Value	525,625,000	533,125,000
Level 2 \| Fair Value \| Term Loan A
FAIR VALUE MEASUREMENTS:
Fair Value	258,047,000	262,556,000
Level 2 \| Fair Value \| Term Loan B
FAIR VALUE MEASUREMENTS:
Fair Value	585,900,000	589,125,000
Level 2 \| Fair Value \| Deerfield Bank Credit Facility
FAIR VALUE MEASUREMENTS:
Fair Value	25,536,000	19,950,000
Level 3 \| Carrying Value
FAIR VALUE MEASUREMENTS:
Active program contracts payable	82,129,000	104,356,000
Future program liabilities	186,038,000	140,535,000
Level 3 \| Fair Value
FAIR VALUE MEASUREMENTS:
Active program contracts payable	78,882,000	102,768,000
Future program liabilities	$ 158,680,000	$ 120,922,000
Discount rate used to determine the fair value of active and future program liabilities (as a percent)	8.00%	8.00%

Represents the fair value of future program liabilities.

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Represents the number of VIEs who classify investments as trading securities during the reporting period.

+ References

No definition available.

+ Details

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Namespace Prefix:	sbgi_
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Balance Type:	na
Period Type:	duration

- Definition

Represents the fair value of active program contracts payable.

+ References

No definition available.

+ Details

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Namespace Prefix:	sbgi_
Data Type:	xbrli:monetaryItemType
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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13476-108611

+ Details

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

+ Details

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Trading Securities which consist of all investments in certain debt and equity securities that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for which an entity has elected the fair value option. Trading generally reflects active and frequent buying and selling, and trading securities are generally used with the objective of generating profits on short-term differences in price, but this category of investments may also include items which are not intended to be sold in the near term or for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

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