Name:	gtn_DefinedBenefitPlanFairValueOfPlanAssetsTableTextBlock
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Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans.

No definition available.

Name:	gtn_ScheduleOfAllocationOfPlanAssetsByAssetCategoryTableTextBlock
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Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 715
-SubTopic 20
-Subparagraph (d)(5)
-Name Accounting Standards Codification
-Paragraph 1
-Section 50
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Name:	us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock
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Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (k)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Name:	us-gaap_ScheduleOfAssumptionsUsedTableTextBlock
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Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 715
-SubTopic 20
-Subparagraph (f)
-Name Accounting Standards Codification
-Paragraph 1
-Section 50
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Name:	us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock
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Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 715
-SubTopic 20
-Subparagraph (h)
-Name Accounting Standards Codification
-Paragraph 1
-Section 50
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Name:	us-gaap_ScheduleOfNetBenefitCostsTableTextBlock
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Tabular disclosure of net funded status of pension plans and/or other employee benefit plans.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Name:	us-gaap_ScheduleOfNetFundedStatusTableTextBlock
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- References

No definition available.