Condensed Consolidating Statements of Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Condensed Income Statements, Captions [Line Items]
Net revenue	$ 271,079us-gaap_SalesRevenueServicesNet	$ 292,044us-gaap_SalesRevenueServicesNet
Operating expenses:
Content costs	100,807us-gaap_OperatingCostsAndExpenses	108,493us-gaap_OperatingCostsAndExpenses
Selling, general & administrative expenses	116,307	115,335
Depreciation and amortization	25,311us-gaap_DepreciationAndAmortization	28,881us-gaap_DepreciationAndAmortization
LMA fees	2,498us-gaap_LicenseCosts	1,557us-gaap_LicenseCosts
Corporate expenses (including stock-based compensation expense of $3,863 and $4,091, respectively)	13,462us-gaap_GeneralAndAdministrativeExpense	19,194us-gaap_GeneralAndAdministrativeExpense
Loss on sale of assets or stations	819us-gaap_GainLossOnSaleOfOtherAssets	(538)us-gaap_GainLossOnSaleOfOtherAssets
Total operating expenses	259,204us-gaap_OperatingExpenses	272,922us-gaap_OperatingExpenses
Operating income	11,875us-gaap_OperatingIncomeLoss	19,122us-gaap_OperatingIncomeLoss
Non-operating (expense) income:
Interest expense	(34,984)us-gaap_InterestExpense	(36,265)us-gaap_InterestExpense
Interest income	358us-gaap_InvestmentIncomeInterest	331us-gaap_InvestmentIncomeInterest
Other income (expense), net	379us-gaap_OtherNonoperatingIncomeExpense	(65)us-gaap_OtherNonoperatingIncomeExpense
Total non-operating expense, net	(34,247)us-gaap_NonoperatingIncomeExpense	(35,999)us-gaap_NonoperatingIncomeExpense
Loss before income taxes	(22,372)	(16,877)
Income tax benefit	10,357us-gaap_IncomeTaxExpenseBenefit	7,608us-gaap_IncomeTaxExpenseBenefit
(Loss) income from continuing operations	(12,015)	(9,269)
(Loss) earnings from consolidated subsidiaries	0cmls_IncomeLossFromSubsidiaries	0cmls_IncomeLossFromSubsidiaries
Net loss	(12,015)us-gaap_NetIncomeLoss	(9,269)us-gaap_NetIncomeLoss
Cumulus Media Inc. (Parent Guarantor)
Condensed Income Statements, Captions [Line Items]
Net revenue	0	0
Operating expenses:
Content costs	0	0
Selling, general & administrative expenses	0	0
Depreciation and amortization	0	0
LMA fees	0	0
Corporate expenses (including stock-based compensation expense of $3,863 and $4,091, respectively)	0	0
Loss on sale of assets or stations	0	0
Total operating expenses	0	0
Operating income	0	0
Non-operating (expense) income:
Interest expense	(2,184)	(2,576)
Interest income	0	0
Other income (expense), net	0	0
Total non-operating expense, net	(2,184)	(2,576)
Loss before income taxes	(2,184)	(2,576)
Income tax benefit	867	942
(Loss) income from continuing operations	(1,317)	(1,634)
(Loss) earnings from consolidated subsidiaries	(10,698)	(7,635)
Net loss	(12,015)	(9,269)
Cumulus Media Holdings Inc. (Subsidiary Issuer)
Condensed Income Statements, Captions [Line Items]
Net revenue	125	104
Operating expenses:
Content costs	0	0
Selling, general & administrative expenses	0	0
Depreciation and amortization	260	458
LMA fees	0	0
Corporate expenses (including stock-based compensation expense of $3,863 and $4,091, respectively)	13,462	19,194
Loss on sale of assets or stations	0	0
Total operating expenses	13,722	19,652
Operating income	(13,597)	(19,548)
Non-operating (expense) income:
Interest expense	(32,753)	(33,644)
Interest income	0	0
Other income (expense), net	0	0
Total non-operating expense, net	(32,753)	(33,644)
Loss before income taxes	(46,350)	(53,192)
Income tax benefit	28,242	19,061
(Loss) income from continuing operations	(18,108)	(34,131)
(Loss) earnings from consolidated subsidiaries	7,410	26,496
Net loss	(10,698)	(7,635)
Subsidiary Guarantors
Condensed Income Statements, Captions [Line Items]
Net revenue	270,954	291,940
Operating expenses:
Content costs	100,807	108,493
Selling, general & administrative expenses	115,776	114,744
Depreciation and amortization	25,051	28,423
LMA fees	2,498	1,557
Corporate expenses (including stock-based compensation expense of $3,863 and $4,091, respectively)	0	0
Loss on sale of assets or stations	819	(538)
Total operating expenses	244,951	252,679
Operating income	26,003	39,261
Non-operating (expense) income:
Interest expense	0	0
Interest income	358	331
Other income (expense), net	379	(65)
Total non-operating expense, net	737	266
Loss before income taxes	26,740	39,527
Income tax benefit	(10,617)	(12,599)
(Loss) income from continuing operations	16,123	26,928
(Loss) earnings from consolidated subsidiaries	(8,713)	(432)
Net loss	7,410	26,496
Subsidiary Non-guarantors
Condensed Income Statements, Captions [Line Items]
Net revenue	0	0
Operating expenses:
Content costs	0	0
Selling, general & administrative expenses	531	591
Depreciation and amortization	0	0
LMA fees	0	0
Corporate expenses (including stock-based compensation expense of $3,863 and $4,091, respectively)	0	0
Loss on sale of assets or stations	0	0
Total operating expenses	531	591
Operating income	(531)	(591)
Non-operating (expense) income:
Interest expense	(47)	(45)
Interest income	0	0
Other income (expense), net	0	0
Total non-operating expense, net	(47)	(45)
Loss before income taxes	(578)	(636)
Income tax benefit	(8,135)	204
(Loss) income from continuing operations	(8,713)	(432)
(Loss) earnings from consolidated subsidiaries	0	0
Net loss	(8,713)	(432)
Eliminations
Condensed Income Statements, Captions [Line Items]
Net revenue	0	0
Operating expenses:
Content costs	0	0
Selling, general & administrative expenses	0	0
Depreciation and amortization	0	0
LMA fees	0	0
Corporate expenses (including stock-based compensation expense of $3,863 and $4,091, respectively)	0	0
Loss on sale of assets or stations	0	0
Total operating expenses	0	0
Operating income	0	0
Non-operating (expense) income:
Interest expense	0	0
Interest income	0	0
Other income (expense), net	0	0
Total non-operating expense, net	0	0
Loss before income taxes	0	0
Income tax benefit	0	0
(Loss) income from continuing operations	0	0
(Loss) earnings from consolidated subsidiaries	12,001	(18,429)
Net loss	$ 12,001	$ (18,429)

Income loss from subsidiaries.

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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.

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Amount of gain (loss) on sale or disposal of other assets.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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

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Costs incurred and are directly related to generating license revenue. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

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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.

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