Supplemental Condensed Consolidating Financial Information (Condensed Consolidating Statements of Operations) (Detail) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]                      
Net revenue $ 308,825 $ 289,441 $ 299,334 $ 271,079 $ 329,247 $ 313,885 $ 328,247 $ 292,044 $ 1,168,679 $ 1,263,423 $ 1,026,138
Operating expenses:                      
Content costs                 396,426 433,596 264,871
Selling, general & administrative expenses                 477,327 470,441 403,381
Depreciation and amortization                 102,105 115,275 112,511
LMA fees                 10,129 7,195 3,716
Corporate expenses (including stock-based compensation expense of $21,033, $17,638, and $10,804, respectively)                 73,403 76,428 59,830
Loss (gain) on sale of assets or stations                 2,856 (1,342) (3,685)
Gain on derivative instrument                 0 0 (1,852)
Impairment of intangible assets and goodwill                 565,584 0 0
Impairment charges - equity interest in Pulser Media Inc.                 19,364 0 0
Total operating expenses                 1,647,194 1,101,593 838,772
Operating (loss) income 28,821 (567,214) 48,003 11,875 42,375 41,900 58,433 19,122 (478,515) 161,830 187,366
Non-operating (expense) income:                      
Interest (expense) income, net                 (141,246) (144,145) (176,981)
Gain (loss) on early extinguishment of debt                 13,222 0 (34,934)
Other income (expense), net                 14,205 4,338 (302)
Total non-operating expense, net                 (113,819) (139,807) (212,217)
(Loss) income from continuing operations before income taxes 8,081 (603,034) 24,991 (22,372) 6,952 6,048 25,900 (16,877) (592,334) 22,023 (24,851)
Income tax benefit (expense)                 45,840 (10,254) 68,464
(Loss) income from continuing operations                 (546,494) 11,769 43,613
Income from discontinued operations, net of taxes                 0 0 132,470
(Loss) earnings from consolidated subsidiaries                 0 0 0
Net (loss) income $ (4,599) $ (542,179) $ 12,299 $ (12,015) $ 3,361 $ 2,540 $ 15,137 $ (9,269) (546,494) 11,769 176,083
Eliminations                      
Condensed Financial Statements, Captions [Line Items]                      
Net revenue                 0 0 0
Operating expenses:                      
Content costs                 0 0 0
Selling, general & administrative expenses                 0 0 0
Depreciation and amortization                 0 0 0
LMA fees                 0 0 0
Corporate expenses (including stock-based compensation expense of $21,033, $17,638, and $10,804, respectively)                 0 0 0
Loss (gain) on sale of assets or stations                 0 0 0
Gain on derivative instrument                     0
Impairment of intangible assets and goodwill                 0    
Impairment charges - equity interest in Pulser Media Inc.                 0    
Total operating expenses                 0 0 0
Operating (loss) income                 0 0 0
Non-operating (expense) income:                      
Interest (expense) income, net                 0 0 0
Gain (loss) on early extinguishment of debt                 0   0
Other income (expense), net                 0 0 0
Total non-operating expense, net                 0 0 0
(Loss) income from continuing operations before income taxes                 0 0 0
Income tax benefit (expense)                 0 0 0
(Loss) income from continuing operations                 0 0 0
Income from discontinued operations, net of taxes                     0
(Loss) earnings from consolidated subsidiaries                 967,479 (164,839) (521,352)
Net (loss) income                 967,479 (164,839) (521,352)
Cumulus Media Inc. (Parent Guarantor)                      
Condensed Financial Statements, Captions [Line Items]                      
Net revenue                 0 0 0
Operating expenses:                      
Content costs                 0 0 0
Selling, general & administrative expenses                 0 0 0
Depreciation and amortization                 0 0 0
LMA fees                 0 0 0
Corporate expenses (including stock-based compensation expense of $21,033, $17,638, and $10,804, respectively)                 0 0 0
Loss (gain) on sale of assets or stations                 0 0 0
Gain on derivative instrument                     0
Impairment of intangible assets and goodwill                 0    
Impairment charges - equity interest in Pulser Media Inc.                 0    
Total operating expenses                 0 0 0
Operating (loss) income                 0 0 0
Non-operating (expense) income:                      
Interest (expense) income, net                 (8,735) (9,349) (11,765)
Gain (loss) on early extinguishment of debt                 0   0
Other income (expense), net                 0 0 0
Total non-operating expense, net                 (8,735) (9,349) (11,765)
(Loss) income from continuing operations before income taxes                 (8,735) (9,349) (11,765)
Income tax benefit (expense)                 3,494 3,739 4,706
(Loss) income from continuing operations                 (5,241) (5,610) (7,059)
Income from discontinued operations, net of taxes                     0
(Loss) earnings from consolidated subsidiaries                 (541,253) 17,379 183,142
Net (loss) income                 (546,494) 11,769 176,083
Cumulus Media Holdings Inc. (Subsidiary Issuer)                      
Condensed Financial Statements, Captions [Line Items]                      
Net revenue                 500 479 1,063
Operating expenses:                      
Content costs                 0 0 0
Selling, general & administrative expenses                 0 0 0
Depreciation and amortization                 1,525 1,619 1,913
LMA fees                 0 0 0
Corporate expenses (including stock-based compensation expense of $21,033, $17,638, and $10,804, respectively)                 73,403 76,428 59,830
Loss (gain) on sale of assets or stations                 0 0 0
Gain on derivative instrument                     0
Impairment of intangible assets and goodwill                 0    
Impairment charges - equity interest in Pulser Media Inc.                 0    
Total operating expenses                 74,928 78,047 61,743
Operating (loss) income                 (74,428) (77,568) (60,680)
Non-operating (expense) income:                      
Interest (expense) income, net                 (132,754) (135,920) (165,156)
Gain (loss) on early extinguishment of debt                 13,222   (34,934)
Other income (expense), net                 0 0 0
Total non-operating expense, net                 (119,532) (135,920) (200,090)
(Loss) income from continuing operations before income taxes                 (193,960) (213,488) (260,770)
Income tax benefit (expense)                 77,584 81,993 104,308
(Loss) income from continuing operations                 (116,376) (131,495) (156,462)
Income from discontinued operations, net of taxes                     0
(Loss) earnings from consolidated subsidiaries                 (424,877) 148,874 339,604
Net (loss) income                 (541,253) 17,379 183,142
Subsidiary Guarantors                      
Condensed Financial Statements, Captions [Line Items]                      
Net revenue                 1,168,179 1,262,944 1,025,075
Operating expenses:                      
Content costs                 396,426 433,596 264,871
Selling, general & administrative expenses                 475,268 468,349 401,122
Depreciation and amortization                 100,580 113,656 110,598
LMA fees                 10,129 7,195 3,716
Corporate expenses (including stock-based compensation expense of $21,033, $17,638, and $10,804, respectively)                 0 0 0
Loss (gain) on sale of assets or stations                 2,856 (1,342) (3,685)
Gain on derivative instrument                     (1,852)
Impairment of intangible assets and goodwill                 565,584    
Impairment charges - equity interest in Pulser Media Inc.                 19,364    
Total operating expenses                 1,570,207 1,021,454 774,770
Operating (loss) income                 (402,028) 241,490 250,305
Non-operating (expense) income:                      
Interest (expense) income, net                 433 1,388 4
Gain (loss) on early extinguishment of debt                 0   0
Other income (expense), net                 14,205 4,338 (302)
Total non-operating expense, net                 14,638 5,726 (298)
(Loss) income from continuing operations before income taxes                 (387,390) 247,216 250,007
Income tax benefit (expense)                 (36,138) (96,928) (41,479)
(Loss) income from continuing operations                 (423,528) 150,288 208,528
Income from discontinued operations, net of taxes                     132,470
(Loss) earnings from consolidated subsidiaries                 (1,349) (1,414) (1,394)
Net (loss) income                 (424,877) 148,874 339,604
Subsidiary Non-guarantors                      
Condensed Financial Statements, Captions [Line Items]                      
Net revenue                 0 0 0
Operating expenses:                      
Content costs                 0 0 0
Selling, general & administrative expenses                 2,059 2,092 2,259
Depreciation and amortization                 0 0 0
LMA fees                 0 0 0
Corporate expenses (including stock-based compensation expense of $21,033, $17,638, and $10,804, respectively)                 0 0 0
Loss (gain) on sale of assets or stations                 0 0 0
Gain on derivative instrument                     0
Impairment of intangible assets and goodwill                 0    
Impairment charges - equity interest in Pulser Media Inc.                 0    
Total operating expenses                 2,059 2,092 2,259
Operating (loss) income                 (2,059) (2,092) (2,259)
Non-operating (expense) income:                      
Interest (expense) income, net                 (190) (264) (64)
Gain (loss) on early extinguishment of debt                 0   0
Other income (expense), net                 0 0 0
Total non-operating expense, net                 (190) (264) (64)
(Loss) income from continuing operations before income taxes                 (2,249) (2,356) (2,323)
Income tax benefit (expense)                 900 942 929
(Loss) income from continuing operations                 (1,349) (1,414) (1,394)
Income from discontinued operations, net of taxes                     0
(Loss) earnings from consolidated subsidiaries                 0 0  
Net (loss) income                 $ (1,349) $ (1,414) $ (1,394)