CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
Current Assets:
Cash and cash equivalents	$ 356,851	$ 313,991
Restricted cash	2,879	1,149
Accounts receivable, trade (less allowance for doubtful accounts)	280,065	295,149
Prepaid expenses and other current assets	153,941	127,058
Amounts due from affiliates	19,841	25,127
Deferred tax asset	177,545	103,645
Investment securities pledged as collateral	272,121	235,932
Assets distributed to shareholders/member in 2011	0	564,231
Total current assets	1,263,243	1,666,282
Property, plant and equipment, net of accumulated depreciation	3,248,536	3,361,590
Investment securities pledged as collateral	272,121	235,932
Derivative contracts	7,234	0
Other assets	43,106	48,929
Deferred tax asset	(108,513)	99,287
Amortizable intangible assets, net of accumulated amortization	263,698	292,144
Indefinite-lived cable television franchises	1,240,228	1,240,228
Other indefinite-lived intangible assets	66,895	66,895
Goodwill	442,067	442,067
Deferred financing and other costs, net of accumulated amortization	127,927	140,064
Assets distributed to shareholders/member in 2011	0	1,273,674
Total Assets	6,975,055	8,867,092
Current Liabilities:
Accounts payable	464,521	435,816
Accrued liabilities	576,482	634,475
Amounts due to affiliates	30,720	31,517
Deferred revenue	57,349	52,732
Liabilities under derivative contracts	169,492	47,251
Credit facility debt	208,164	157,452
Collateralized indebtedness	183,823	161,358
Capital lease obligations	3,894	1,531
Notes payable	739	0
Senior notes	271,442	325,773
Liabilities distributed to shareholders/member in 2011	0	336,491
Total current liabilities	1,966,626	2,184,396
Deferred revenue	9,776	10,946
Liabilities under derivative contracts	11,822	179,327
Other liabilities	288,258	273,918
Deferred tax liability	108,513	(99,287)
Credit facility debt	4,775,106	5,599,058
Collateralized indebtedness	241,999	191,248
Capital lease obligations	31,676	29,706
Senior notes and debentures	4,981,086	5,242,420
Liabilities distributed to shareholders/member in 2011	0	1,436,808
Total liabilities	12,414,862	15,147,827
Commitments and contingencies
Redeemable noncontrolling interests	15,642	14,698
Stockholders'/Member Deficiency:
Preferred Stock, $.01 par value, 50,000,000 shares authorized, none issued	0	0
Paid-in capital	1,107,445	6,465
Accumulated deficit	(5,345,432)	(5,494,829)
Total stockholders'/member's deficiency before treasury stock, accumulated other comprehensive income and noncontrolling interest	(4,234,628)	(5,485,027)
Treasury stock, at cost	(1,199,603)	(788,566)
Accumulated other comprehensive loss	(23,370)	(23,325)
Total stockholders'/member deficiency	(5,457,601)	(6,296,918)
Noncontrolling interest	2,152	1,485
Total deficiency	(5,455,449)	(6,295,433)
Total liabilities and stockholders'/member's deficiency	6,975,055	8,867,092
CSC Holdings, LLC [Member]
Current Assets:
Cash and cash equivalents	356,451	266,914
Restricted cash	2,879	1,149
Accounts receivable, trade (less allowance for doubtful accounts)	280,065	295,149
Prepaid expenses and other current assets	147,828	122,385
Amounts due from affiliates	508,692	515,698
Deferred tax asset	113,385	155,487
Investment securities pledged as collateral	272,121	235,932
Assets distributed to shareholders/member in 2011	0	564,231
Total current assets	1,681,421	2,156,945
Property, plant and equipment, net of accumulated depreciation	3,248,536	3,361,590
Investment securities pledged as collateral	272,121	235,932
Derivative contracts	7,234	0
Other assets	43,106	48,929
Deferred tax asset	(508,181)	(368,647)
Amortizable intangible assets, net of accumulated amortization	263,698	292,144
Indefinite-lived cable television franchises	1,240,228	1,240,228
Other indefinite-lived intangible assets	66,895	66,895
Goodwill	442,067	442,067
Deferred financing and other costs, net of accumulated amortization	88,158	98,188
Assets distributed to shareholders/member in 2011	0	1,229,374
Total Assets	7,353,464	9,172,292
Current Liabilities:
Accounts payable	464,521	435,816
Accrued liabilities	527,165	571,711
Amounts due to affiliates	30,706	31,200
Deferred revenue	57,349	52,732
Liabilities under derivative contracts	169,492	47,251
Credit facility debt	208,164	157,452
Collateralized indebtedness	183,823	161,358
Capital lease obligations	3,894	1,531
Notes payable	739	0
Senior notes	244,617	325,773
Liabilities distributed to shareholders/member in 2011	0	336,491
Total current liabilities	1,890,470	2,121,315
Deferred revenue	9,776	10,946
Liabilities under derivative contracts	11,822	179,327
Other liabilities	286,434	268,919
Deferred tax liability	508,181	368,647
Credit facility debt	4,775,106	5,599,058
Collateralized indebtedness	241,999	191,248
Capital lease obligations	31,676	29,706
Senior notes and debentures	2,841,598	3,076,732
Liabilities distributed to shareholders/member in 2011	0	1,460,456
Total liabilities	10,597,062	13,306,354
Commitments and contingencies
Redeemable noncontrolling interests	15,642	14,698
Stockholders'/Member Deficiency:
Accumulated deficit	(3,662,287)	(3,375,506)
Senior notes due from Cablevision	(753,717)	(753,717)
Other member's equity	1,177,982	2,303
Total stockholders'/member's deficiency before treasury stock, accumulated other comprehensive income and noncontrolling interest	(3,238,022)	(4,126,920)
Accumulated other comprehensive loss	(23,370)	(23,325)
Total stockholders'/member deficiency	(3,261,392)	(4,150,245)
Noncontrolling interest	2,152	1,485
Total deficiency	(3,259,240)	(4,148,760)
Total liabilities and stockholders'/member's deficiency	7,353,464	9,172,292
CNYG Class A Common Stock [Member]
Stockholders'/Member Deficiency:
Common stock	2,818	2,796
CNYG Class B Common Stock [Member]
Stockholders'/Member Deficiency:
Common stock	541	541
RMG Class A Common Stock [Member]
Stockholders'/Member Deficiency:
Common stock	0	0
RMG Class B Common Stock [Member]
Stockholders'/Member Deficiency:
Common stock	$ 0	$ 0