CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	CSC Holdings	Parent [Member]	Parent [Member] CSC Holdings	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] CSC Holdings	Retained Earnings [Member]	Treasury Stock, Common	AOCI Attributable to Parent [Member]	AOCI Attributable to Parent [Member] CSC Holdings	Noncontrolling Interest [Member]	Noncontrolling Interest [Member] CSC Holdings	Common Class A Common Stock	Common Class B Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total deficiency		$ (437,925)		$ (425,687)		$ (412,836)				$ (12,851)		$ (12,238)
Beginning balance at Dec. 31, 2023	$ (434,418)		$ (422,180)		$ 187,186		$ (601,075)	$ 0	$ (12,851)		$ (12,238)		$ 2,718	$ 1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss) attributable to CSC Holdings, LLC sole member	(21,193)	(21,193)	(21,193)	(21,193)		(21,193)	(21,193)
Net income attributable to noncontrolling interests	8,297	8,297									8,297	8,297
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(4,255)	(4,255)	(4,255)	(4,255)					4,255	(4,255)
Foreign currency translation adjustment	(612)	(612)	(612)	(612)					(612)	(612)
Share-based compensation expense (equity classified)	6,484	6,484	6,484	6,484	6,484	6,484
Other, net	2,082		2,082		2,043			(10)					49
Ending balance at Mar. 31, 2024	(435,105)		(431,164)		195,713		(622,268)	(10)	(9,208)		(3,941)		2,767	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash distributions to parent		(3,775)		(3,775)		(3,775)
Beginning balance at Dec. 31, 2023	(434,418)		(422,180)		187,186		(601,075)	0	(12,851)		(12,238)		2,718	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss) attributable to CSC Holdings, LLC sole member	(5,832)	(5,832)
Net income attributable to noncontrolling interests	14,638	14,638
Ending balance at Jun. 30, 2024	(396,694)		(399,094)		209,992		(606,907)	(10)	(6,784)		2,400		2,773	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends, Cash		(4,638)
Total deficiency		(438,611)		(434,670)		(425,462)				(9,208)		(3,941)
Beginning balance at Mar. 31, 2024	(435,105)		(431,164)		195,713		(622,268)	(10)	(9,208)		(3,941)		2,767	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss) attributable to CSC Holdings, LLC sole member	15,361	15,361	15,361	15,361		15,361	15,361
Net income attributable to noncontrolling interests	6,341	6,341									6,341	6,341
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(2,629)	(2,629)	(2,629)	(2,629)					2,629	(2,629)
Foreign currency translation adjustment	(205)	(205)	(205)	(205)					(205)	(205)
Share-based compensation expense (equity classified)	15,147	15,147	15,147	15,147	15,147	15,147
Other, net	(862)		(862)		(868)			0					6
Ending balance at Jun. 30, 2024	(396,694)		(399,094)		209,992		(606,907)	(10)	(6,784)		2,400		2,773	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends, Cash		(863)
Cash distributions to parent		(863)		(863)		(863)
Total deficiency		(400,201)		(402,601)		(395,817)				(6,784)		2,400
Total deficiency		(459,620)		(472,023)		(468,197)				(3,826)		12,403
Beginning balance at Dec. 31, 2024	(456,832)		(469,235)		233,953		(703,993)	(10)	(3,826)		12,403		2,799	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss) attributable to CSC Holdings, LLC sole member	(75,676)	(78,122)	(75,676)	(78,122)		(78,122)	(75,676)
Net income attributable to noncontrolling interests	4,405	4,405									4,405	4,405
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	1,125	1,125	1,125	1,125					(1,125)	1,125
Foreign currency translation adjustment	(54)	(54)	(54)	(54)					(54)	(54)
Share-based compensation expense (equity classified)	11,587	11,587	11,587	11,587	11,587	11,587
Other, net	(8,497)		(8,497)		(8,543)			0					46
Ending balance at Mar. 31, 2025	(526,192)		(543,000)		236,997		(779,669)	(10)	(5,005)		16,808		2,845	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash distributions to parent		(8,547)		(8,547)		(8,547)
Beginning balance at Dec. 31, 2024	(456,832)		(469,235)		233,953		(703,993)	(10)	(3,826)		12,403		2,799	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss) attributable to CSC Holdings, LLC sole member	(171,927)	(179,405)
Net income attributable to noncontrolling interests	12,670	12,670
Ending balance at Jun. 30, 2025	(625,494)		(624,115)		247,891		(875,920)	(10)	(772)		(1,379)		2,854	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends, Cash		(9,738)
Total deficiency		(531,476)		(548,284)		(543,279)				(5,005)		16,808
Beginning balance at Mar. 31, 2025	(526,192)		(543,000)		236,997		(779,669)	(10)	(5,005)		16,808		2,845	1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss) attributable to CSC Holdings, LLC sole member	(96,251)	(101,283)	(96,251)	(101,283)		(101,283)	(96,251)
Net income attributable to noncontrolling interests	8,265	8,265									8,265	8,265
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(3,295)	(3,295)	(3,295)	(3,295)					3,295	(3,295)
Foreign currency translation adjustment	938	938	938	938					938	938
Share-based compensation expense (equity classified)	12,054	12,054	12,054	12,054	12,054	12,054
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(26,452)	(26,452)		26,452							(26,452)
Other, net	(1,151)		(1,151)		(1,160)								9
Ending balance at Jun. 30, 2025	$ (625,494)		$ (624,115)		$ 247,891		$ (875,920)	$ (10)	$ (772)		$ (1,379)		$ 2,854	$ 1,842
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends, Cash		(1,191)
Cash distributions to parent		(1,148)		(1,148)		(1,148)
Total deficiency		$ (635,807)		$ (634,428)		$ (633,656)				$ (772)		$ (1,379)