CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current Assets:
Accounts receivable, trade allowance for doubtful accounts	$ 14,155	$ 13,521
Property, plant and equipment, accumulated depreciation	9,302,246	9,295,297
Amortizable intangible assets, accumulated amortization	90,534	86,193
Deferred financing costs, accumulated amortization	71,531	67,156
Stockholders'/Member's Deficiency:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares issued (in shares)	0	0
Treasury stock (in shares)	78,024,481	77,189,014
CNYG Class A Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	800,000,000	800,000,000
Common stock, shares issued (in shares)	291,124,361	287,750,132
Common stock, shares outstanding (in shares)	213,099,880	210,561,118
CNYG Class B Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	320,000,000	320,000,000
Common stock, shares issued (in shares)	54,137,673	54,137,673
Common stock, shares outstanding (in shares)	54,137,673	54,137,673
RMG Class A Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	600,000,000	600,000,000
Common stock, shares issued (in shares)	0	0
RMG Class B Common Stock [Member]
Stockholders'/Member's Deficiency:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	160,000,000	160,000,000
Common stock, shares issued (in shares)	0	0
CSC Holdings, LLC [Member]
Current Assets:
Accounts receivable, trade allowance for doubtful accounts	14,155	13,521
Property, plant and equipment, accumulated depreciation	9,302,246	9,295,297
Amortizable intangible assets, accumulated amortization	90,534	86,193
Deferred financing costs, accumulated amortization	$ 57,002	$ 54,134
Stockholders'/Member's Deficiency:
Other member's equity, membership units issued (in shares)	17,631,479	17,631,479
Other member's equity, membership units outstanding (in shares)	17,631,479	17,631,479