Segment Information - Separate Financial Data for Each of Company's Operating Segment (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenue from advertising and retransmission consent	$ 70,612	$ 65,281	$ 198,631	$ 188,223
Revenue from spectrum usage rights	263,943		263,943
Net revenue	334,555	65,281	462,574	188,223
Cost of revenue - television (spectrum usage rights)	12,131		12,131
Cost of revenue - digital media	9,910	2,281	20,424	6,493
Direct operating expenses	30,231	28,238	87,238	84,341
Selling, general and administrative expenses	12,813	11,949	36,043	34,794
Depreciation and amortization	4,337	3,812	12,460	11,724
Operating income (loss)	256,982	13,273	274,290	34,246
Corporate expenses	8,209	5,728	19,695	16,625
Foreign currency transaction (gain) loss	(58)		293
Interest expense	(3,756)	(3,894)	(11,084)	(11,619)
Interest income	256	71	475	196
Income before income taxes	253,482	9,450	263,681	22,823
Capital expenditures	2,366	2,336	9,174	6,922
Total assets	$ 764,421		$ 764,421		$ 517,921
Percentage change in revenue from advertising and retransmission consent	8.00%		6.00%
Percentage change in net revenue	412.00%		146.00%
Percentage change in direct operating expenses	7.00%		3.00%
Percentage change in selling, general and administrative expenses	7.00%		4.00%
Percentage change in depreciation and amortization	14.00%		6.00%
Percentage change in segment operating profit (loss)	1295.00%		478.00%
Percentage change in corporate expenses	43.00%		18.00%
Percentage change in operating income (loss)	1836.00%		701.00%
Percentage change in interest expenses	(4.00%)		(5.00%)
Percentage change in interest income	261.00%		142.00%
Percentage change in income (loss) before income taxes	2582.00%		1055.00%
Operating Segments
Segment Reporting Information [Line Items]
Operating income (loss)	$ 265,133	19,001	$ 294,278	50,871
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Corporate expenses	8,209	5,728	19,695	16,625
Television
Segment Reporting Information [Line Items]
Revenue from advertising and retransmission consent	36,547	40,363	112,021	116,143
Direct operating expenses	14,365	15,604	43,992	46,113
Selling, general and administrative expenses	5,796	5,547	16,524	16,186
Depreciation and amortization	2,489	2,614	7,452	8,186
Capital expenditures	1,863	1,641	7,815	4,199
Total assets	$ 559,793		$ 559,793		363,852
Percentage change in revenue from advertising and retransmission consent	(9.00%)		(4.00%)
Percentage change in direct operating expenses	(8.00%)		(5.00%)
Percentage change in selling, general and administrative expenses	4.00%		2.00%
Percentage change in depreciation and amortization	(5.00%)		(9.00%)
Percentage change in segment operating profit (loss)	1501.00%		548.00%
Television \| Operating Segments
Segment Reporting Information [Line Items]
Operating income (loss)	$ 265,709	16,598	$ 295,865	45,658
Radio
Segment Reporting Information [Line Items]
Revenue from advertising and retransmission consent	16,934	19,169	49,816	55,605
Direct operating expenses	11,306	11,284	33,362	33,510
Selling, general and administrative expenses	4,647	5,138	13,932	14,976
Depreciation and amortization	648	847	2,036	2,479
Capital expenditures	453	660	1,296	2,492
Total assets	$ 126,812		$ 126,812		129,825
Percentage change in revenue from advertising and retransmission consent	(12.00%)		(10.00%)
Percentage change in direct operating expenses	0.00%		0.00%
Percentage change in selling, general and administrative expenses	(10.00%)		(7.00%)
Percentage change in depreciation and amortization	(23.00%)		(18.00%)
Percentage change in segment operating profit (loss)	(82.00%)		(90.00%)
Radio \| Operating Segments
Segment Reporting Information [Line Items]
Operating income (loss)	$ 333	1,900	$ 486	4,640
Digital
Segment Reporting Information [Line Items]
Revenue from advertising and retransmission consent	17,131	5,749	36,794	16,475
Direct operating expenses	4,560	1,350	9,884	4,718
Selling, general and administrative expenses	2,370	1,264	5,587	3,632
Depreciation and amortization	1,200	351	2,972	1,059
Capital expenditures	50	35	63	231
Total assets	$ 77,816		$ 77,816		$ 24,244
Percentage change in revenue from advertising and retransmission consent	198.00%		123.00%
Percentage change in cost of revenue	334.00%		215.00%
Percentage change in direct operating expenses	238.00%		109.00%
Percentage change in selling, general and administrative expenses	88.00%		54.00%
Percentage change in depreciation and amortization	242.00%		181.00%
Digital \| Operating Segments
Segment Reporting Information [Line Items]
Operating income (loss)	$ (909)	$ 503	$ (2,073)	$ 573

Capital additions including non cash additions.

No definition available.

Name:	evc_CapitalAdditionsIncludingNonCashAdditions
Namespace Prefix:	evc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Corporate expenses.

+ References

No definition available.

+ Details

Name:	evc_CorporateExpenses
Namespace Prefix:	evc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cost of revenue from digital media.

+ References

No definition available.

+ Details

Name:	evc_CostOfRevenueFromDigitalMedia
Namespace Prefix:	evc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cost of revenue from television spectrum usage rights.

+ References

No definition available.

+ Details

Name:	evc_CostOfRevenueFromTelevisionSpectrumUsageRights
Namespace Prefix:	evc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage change in cost of revenue.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInCostOfRevenue
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in depreciation and amortization.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInDepreciationAndAmortization
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in direct operating costs.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInDirectOperatingCosts
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in expenses.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInExpenses
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in income loss before income taxes.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInIncomeLossBeforeIncomeTaxes
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in interest expense.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInInterestExpense
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in interest income.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInInterestIncome
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in net revenue.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInNetRevenue
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in operating income (loss).

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInOperatingIncomeLoss
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in operating profit loss.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInOperatingProfitLoss
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in revenue from advertising and retransmission consent.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInRevenueFromAdvertisingAndRetransmissionConsent
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage change in selling, general and administrative expenses.

+ References

No definition available.

+ Details

Name:	evc_PercentageChangeInSellingGeneralAndAdministrativeExpense
Namespace Prefix:	evc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Revenue from advertising and retransmission consent.

+ References

No definition available.

+ Details

Name:	evc_RevenueFromAdvertisingAndRetransmissionConsent
Namespace Prefix:	evc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Revenue from spectrum usage rights.

+ References

No definition available.

+ Details

Name:	evc_RevenueFromSpectrumUsageRights
Namespace Prefix:	evc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

Name:	us-gaap_DepreciationAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The aggregate direct operating costs incurred during the reporting period.

+ References

+ Details

Name:	us-gaap_DirectOperatingCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30700-110894

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30690-110894

+ Details

Name:	us-gaap_ForeignCurrencyTransactionGainLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

+ Details

Name:	us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.9)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

Name:	us-gaap_InterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

+ Details

Name:	us-gaap_InvestmentIncomeInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

Name:	us-gaap_OperatingIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

+ Details

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311

+ Details

Name:	us-gaap_SellingGeneralAndAdministrativeExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=evc_TelevisionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=evc_RadioMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=evc_DigitalMediaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: