Supplemental Condensed Consolidating Financial Information (Condensed Consolidating Balance Sheets) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 131,259	$ 31,657	$ 7,271	$ 32,792
Restricted cash	8,025	7,981
Accounts receivable	231,585	243,428
Trade receivable	4,985	4,146
Assets held for sale	30,150	45,157
Prepaid expenses and other current assets	33,923	26,906
Total current assets	439,927	359,275
Property and equipment, net	162,063	169,437
Broadcast licenses	1,540,183	1,578,066
Other intangible assets, net	116,499	174,530	243,640
Goodwill	135,214	703,354
Investment in consolidated subsidiaries	0	0
Intercompany receivables	0	0
Other assets	18,805	17,726
Total assets	2,412,691	3,002,388
Current liabilities:
Accounts payable and accrued expenses	96,241	118,396
Trade payable	4,550	4,374
Total current liabilities	100,791	122,770
Term loan, net of debt issuance costs/discounts	1,780,357	1,801,416
7.75% senior notes, net of debt issuance costs	603,800	601,485
Other liabilities	31,431	44,804
Intercompany payables	0	0
Deferred income taxes	388,050	415,881
Total liabilities	2,904,429	2,986,356
Stockholders' equity (deficit):
Treasury stock, at cost	(229,310)	(229,310)
Additional paid-in-capital	1,624,815	1,621,865
Accumulated (deficit) equity	(1,887,564)	(1,376,844)
Total stockholders’ equity	(491,738)	16,032	541,580	512,740
Total liabilities and stockholders’ equity	2,412,691	3,002,388
Class A Common Stock
Stockholders' equity (deficit):
Common stock	320	320
Class C Common Stock
Stockholders' equity (deficit):
Common stock	1	1
Eliminations
Current assets:
Cash and cash equivalents	0	0	0	0
Restricted cash	0	0
Accounts receivable	0	0
Trade receivable	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Property and equipment, net	0	0
Broadcast licenses	0	0
Other intangible assets, net	0	0
Goodwill	0	0
Investment in consolidated subsidiaries	(3,973,430)	(4,951,251)
Intercompany receivables	(1,951,856)	(1,745,901)
Other assets	(139,186)	(106,035)
Total assets	(6,064,472)	(6,803,187)
Current liabilities:
Accounts payable and accrued expenses	0	0
Trade payable	0	0
Total current liabilities	0	0
Term loan, net of debt issuance costs/discounts	0	0
7.75% senior notes, net of debt issuance costs	0	0
Other liabilities	0	0
Intercompany payables	(1,951,856)	(1,745,901)
Deferred income taxes	(139,186)	(106,035)
Total liabilities	(2,091,042)	(1,851,936)
Stockholders' equity (deficit):
Treasury stock, at cost	0	0
Additional paid-in-capital	(6,457,173)	(6,520,419)
Accumulated (deficit) equity	2,483,743	1,569,168
Total stockholders’ equity	(3,973,430)	(4,951,251)
Total liabilities and stockholders’ equity	(6,064,472)	(6,803,187)
Eliminations | Class A Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Eliminations | Class C Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Cumulus Media Inc. (Parent Guarantor)
Current assets:
Cash and cash equivalents	0	0	0	11,804
Restricted cash	0	0
Accounts receivable	0	0
Trade receivable	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	0	0
Total current assets	0	0
Property and equipment, net	0	0
Broadcast licenses	0	0
Other intangible assets, net	0	0
Goodwill	0	0
Investment in consolidated subsidiaries	(388,509)	110,550
Intercompany receivables	0	0
Other assets	0	0
Total assets	(388,509)	110,550
Current liabilities:
Accounts payable and accrued expenses	0	0
Trade payable	0	0
Total current liabilities	0	0
Term loan, net of debt issuance costs/discounts	0	0
7.75% senior notes, net of debt issuance costs	0	0
Other liabilities	0	0
Intercompany payables	103,229	94,518
Deferred income taxes	0	0
Total liabilities	103,229	94,518
Stockholders' equity (deficit):
Treasury stock, at cost	(229,310)	(229,310)
Additional paid-in-capital	1,624,815	1,621,865
Accumulated (deficit) equity	(1,887,564)	(1,376,844)
Total stockholders’ equity	(491,738)	16,032
Total liabilities and stockholders’ equity	(388,509)	110,550
Cumulus Media Inc. (Parent Guarantor) | Class A Common Stock
Stockholders' equity (deficit):
Common stock	320	320
Cumulus Media Inc. (Parent Guarantor) | Class C Common Stock
Stockholders' equity (deficit):
Common stock	1	1
Cumulus Media Holdings Inc. (Subsidiary Issuer)
Current assets:
Cash and cash equivalents	131,259	31,657	7,268	20,988
Restricted cash	8,025	7,981
Accounts receivable	0	0
Trade receivable	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	17,321	6,375
Total current assets	156,605	46,013
Property and equipment, net	4,431	3,685
Broadcast licenses	0	0
Other intangible assets, net	0	0
Goodwill	0	0
Investment in consolidated subsidiaries	3,348,992	3,784,551
Intercompany receivables	103,593	95,072
Other assets	21,631	27,491
Total assets	3,635,252	3,956,812
Current liabilities:
Accounts payable and accrued expenses	19,994	31,997
Trade payable	0	0
Total current liabilities	19,994	31,997
Term loan, net of debt issuance costs/discounts	1,780,357	1,801,416
7.75% senior notes, net of debt issuance costs	603,800	601,485
Other liabilities	2,932	3,963
Intercompany payables	1,616,678	1,407,401
Deferred income taxes	0	0
Total liabilities	4,023,761	3,846,262
Stockholders' equity (deficit):
Treasury stock, at cost	0	0
Additional paid-in-capital	275,107	268,673
Accumulated (deficit) equity	(663,616)	(158,123)
Total stockholders’ equity	(388,509)	110,550
Total liabilities and stockholders’ equity	3,635,252	3,956,812
Cumulus Media Holdings Inc. (Subsidiary Issuer) | Class A Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Cumulus Media Holdings Inc. (Subsidiary Issuer) | Class C Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Subsidiary Guarantors
Current assets:
Cash and cash equivalents	0	0	3	0
Restricted cash	0	0
Accounts receivable	0	0
Trade receivable	4,985	4,146
Assets held for sale	30,150	45,157
Prepaid expenses and other current assets	16,602	20,531
Total current assets	51,737	69,834
Property and equipment, net	157,632	165,752
Broadcast licenses	0	0
Other intangible assets, net	116,499	174,530
Goodwill	135,214	703,354
Investment in consolidated subsidiaries	1,012,947	1,056,150
Intercompany receivables	1,848,263	1,650,829
Other assets	135,996	95,716
Total assets	3,458,288	3,916,165
Current liabilities:
Accounts payable and accrued expenses	76,247	86,399
Trade payable	4,550	4,374
Total current liabilities	80,797	90,773
Term loan, net of debt issuance costs/discounts	0	0
7.75% senior notes, net of debt issuance costs	0	0
Other liabilities	28,499	40,841
Intercompany payables	0	0
Deferred income taxes	0	0
Total liabilities	109,296	131,614
Stockholders' equity (deficit):
Treasury stock, at cost	0	0
Additional paid-in-capital	4,191,057	4,219,060
Accumulated (deficit) equity	(842,065)	(434,509)
Total stockholders’ equity	3,348,992	3,784,551
Total liabilities and stockholders’ equity	3,458,288	3,916,165
Subsidiary Guarantors | Class A Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Subsidiary Guarantors | Class C Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Subsidiary Non-guarantors
Current assets:
Cash and cash equivalents	0	0	$ 0	$ 0
Restricted cash	0	0
Accounts receivable	231,585	243,428
Trade receivable	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	0	0
Total current assets	231,585	243,428
Property and equipment, net	0	0
Broadcast licenses	1,540,183	1,578,066
Other intangible assets, net	0	0
Goodwill	0	0
Investment in consolidated subsidiaries	0	0
Intercompany receivables	0	0
Other assets	364	554
Total assets	1,772,132	1,822,048
Current liabilities:
Accounts payable and accrued expenses	0	0
Trade payable	0	0
Total current liabilities	0	0
Term loan, net of debt issuance costs/discounts	0	0
7.75% senior notes, net of debt issuance costs	0	0
Other liabilities	0	0
Intercompany payables	231,949	243,982
Deferred income taxes	527,236	521,916
Total liabilities	759,185	765,898
Stockholders' equity (deficit):
Treasury stock, at cost	0	0
Additional paid-in-capital	1,991,009	2,032,686
Accumulated (deficit) equity	(978,062)	(976,536)
Total stockholders’ equity	1,012,947	1,056,150
Total liabilities and stockholders’ equity	1,772,132	1,822,048
Subsidiary Non-guarantors | Class A Common Stock
Stockholders' equity (deficit):
Common stock	0	0
Subsidiary Non-guarantors | Class C Common Stock
Stockholders' equity (deficit):
Common stock	$ 0	$ 0