CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Current Assets:
Cash and cash equivalents	$ 813,858	$ 702,224
Restricted cash	250	250
Accounts receivable, trade (less allowance for doubtful accounts)	281,213	283,079
Prepaid expenses and other current assets	139,450	158,183
Amounts due from affiliates	2,276	1,520
Deferred tax asset	0	159,824
Investment securities pledged as collateral	577,533	419,354
Total current assets	1,814,580	1,724,434
Property, plant and equipment, net of accumulated depreciation	2,962,069	2,978,353
Other receivables	1,061	1,683
Investment securities pledged as collateral	577,533	696,730
Derivative contracts	20,454	3,385
Other assets	42,206	29,184
Amortizable intangible assets, net of accumulated amortization	43,854	49,952
Indefinite-lived cable television franchises	731,848	731,848
Trademarks and other indefinite-lived intangible assets	7,450	7,450
Goodwill	264,690	264,690
Deferred financing costs, net of accumulated amortization	98,000	103,367
Total assets	6,563,745	6,591,076
Current Liabilities:
Accounts payable	409,894	422,929
Accrued liabilities	556,132	500,925
Amounts due to affiliates	29,610	30,941
Deferred tax liability	24,222	0
Deferred revenue	47,494	47,229
Liabilities under derivative contracts	49,633	99,577
Credit facility debt	61,849	47,463
Collateralized indebtedness	438,758	248,388
Capital lease obligations	15,891	12,025
Notes payable	12,958	3,744
Senior notes	9,200	27,831
Total current liabilities	1,655,641	1,441,052
Deferred revenue	4,826	5,235
Liabilities under derivative contracts	951	47,370
Other liabilities	275,813	381,830
Deferred tax liability	514,872	570,056
Credit facility debt	2,734,020	3,718,682
Collateralized indebtedness	547,425	569,562
Capital lease obligations	29,603	19,265
Notes payable	13,868	1,590
Senior notes and debentures	5,854,733	5,110,684
Total liabilities	11,631,752	11,865,326
Commitments and contingencies
Redeemable noncontrolling interests	9,006	9,294
Stockholders'/Member's Deficiency:
Preferred Stock, $.01 par value, 50,000,000 shares authorized, none issued	0	0
Paid-in capital	841,372	885,601
Accumulated deficit	(4,290,835)	(4,546,299)
Total stockholders'/member's deficiency before treasury stock, accumulated other comprehensive loss and noncontrolling interest	(3,445,928)	(3,657,232)
Treasury stock, at cost (80,072,714 and 78,890,427 CNYG Class A common shares)	(1,591,020)	(1,584,404)
Accumulated other comprehensive loss	(40,524)	(42,694)
Total stockholders'/member's deficiency	(5,077,472)	(5,284,330)
Noncontrolling interest	459	786
Total deficiency	(5,077,013)	(5,283,544)
Total liabilities and stockholders'/member's deficiency	6,563,745	6,591,076
CNYG Class A Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock	2,994	2,925
CNYG Class B Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock	541	541
RMG Class A Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock	0	0
RMG Class B Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock	0	0
CSC Holdings, LLC [Member]
Current Assets:
Cash and cash equivalents	748,843	651,058
Restricted cash	250	250
Accounts receivable, trade (less allowance for doubtful accounts)	281,213	283,079
Prepaid expenses and other current assets	136,948	154,626
Amounts due from affiliates	1,974	115,538
Investment securities pledged as collateral	577,533	419,354
Total current assets	1,746,761	1,623,905
Property, plant and equipment, net of accumulated depreciation	2,962,069	2,978,353
Other receivables	1,061	1,683
Investment securities pledged as collateral	577,533	696,730
Derivative contracts	20,454	3,385
Other assets	42,206	29,184
Amortizable intangible assets, net of accumulated amortization	43,854	49,952
Indefinite-lived cable television franchises	731,848	731,848
Trademarks and other indefinite-lived intangible assets	7,450	7,450
Goodwill	264,690	264,690
Deferred financing costs, net of accumulated amortization	62,179	61,367
Total assets	6,460,105	6,448,547
Current Liabilities:
Accounts payable	409,894	422,929
Accrued liabilities	502,206	443,550
Amounts due to affiliates	153,828	30,887
Deferred tax liability	119,522	60,582
Deferred revenue	47,494	47,229
Liabilities under derivative contracts	49,633	99,577
Credit facility debt	61,849	47,463
Collateralized indebtedness	438,758	248,388
Capital lease obligations	15,891	12,025
Notes payable	12,958	3,744
Total current liabilities	1,812,033	1,416,374
Deferred revenue	4,826	5,235
Liabilities under derivative contracts	951	47,370
Other liabilities	272,096	377,221
Deferred tax liability	523,935	617,837
Credit facility debt	2,734,020	3,718,682
Collateralized indebtedness	547,425	569,562
Capital lease obligations	29,603	19,265
Notes payable	13,868	1,590
Senior notes and debentures	3,061,424	2,309,403
Total liabilities	9,000,181	9,082,539
Commitments and contingencies
Redeemable noncontrolling interests	9,006	9,294
Stockholders'/Member's Deficiency:
Accumulated deficit	(2,115,197)	(2,486,073)
Senior notes due from Cablevision	(611,455)	(611,455)
Other member's equity	217,635	496,150
Total stockholders'/member's deficiency before treasury stock, accumulated other comprehensive loss and noncontrolling interest	(2,509,017)	(2,601,378)
Accumulated other comprehensive loss	(40,524)	(42,694)
Total stockholders'/member's deficiency	(2,549,541)	(2,644,072)
Noncontrolling interest	459	786
Total deficiency	(2,549,082)	(2,643,286)
Total liabilities and stockholders'/member's deficiency	$ 6,460,105	$ 6,448,547