CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Parent [Member]	Retained Earnings (Accumulated Deficit)	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interests	Additional Paid-in Capital [Member]	Treasury Stock, Common	Common Class A Common Stock	Common Class B Common Stock	Organizational Transactions Prior to IPO	Organizational Transactions Prior to IPO Parent [Member]	Organizational Transactions Prior to IPO Additional Paid-in Capital [Member]	Organizational Transactions Prior to IPO Common Class A Common Stock	Organizational Transactions Prior to IPO Common Class B Common Stock	IPO	IPO Parent [Member]	IPO Additional Paid-in Capital [Member]	IPO Common Class A Common Stock
Beginning balance at Dec. 31, 2016	$ 2,042,508	$ 2,042,221	$ (963,312)		$ 1,979	$ 287	$ 3,003,554		$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to Altice USA, Inc. stockholders	1,493,177	1,493,177	1,493,177
Net income attributable to noncontrolling interests	(1,587)					(1,587)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Net Of Tax	12,001	12,001			12,001
Foreign currency translation adjustment, net of income taxes	0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	57,430	57,430					57,430
Adjustments to Additional Paid in Capital, Increase in Carrying Amount of Redeemable Preferred Stock	(163,142)	(163,142)					(163,142)
Adjustments to Additional Paid in Capital, Cash Investment in Affiliate	51,135	51,135					51,135
Receivable from parent	(50,000)	(50,000)					(50,000)
Distributions to stockholders/non-controlling interest	(840,035)	(839,700)				(335)	(839,700)
Recognition of previously unrealized excess tax benefits related to share-based awards in connection with the adoption of ASU 2016-09	310,771	310,771	310,771
Stock Issued During Period, Value, New Issues											$ 2,264,252	$ 2,264,252	$ 2,257,002	$ 2,349	$ 4,901	$ 349,071	$ 349,071	$ 348,950	$ 121
Ending balance at Dec. 31, 2017	5,504,753	5,503,214	840,636		(10,022)	1,539	4,665,229		2,470	4,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to Altice USA, Inc. stockholders	18,833	18,833	18,833
Net income attributable to noncontrolling interests	(1,761)					(1,761)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Net Of Tax	(1,536)	(1,536)			(1,536)
Foreign currency translation adjustment, net of income taxes	706	706			706
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	59,812	59,812					59,812
Redeemable equity vested	169,452	169,452					169,452
Adjustments to Additional Paid in Capital, Increase in Carrying Amount of Redeemable Preferred Stock	(68,169)	(68,169)					(68,169)
Dividend payment	(1,499,935)	(1,499,935)	(536,224)				(963,711)
Class A shares acquired through share repurchase program and retired	(500,000)	(500,000)					(499,720)		(280)
Conversion of Class B to Class A shares, including $2,424 in connection with the Distribution									2,771	(2,771)
Distributions to stockholders/non-controlling interest	(1,499,935)
Impact of i24 Acquisition	(13,649)	(13,649)	(73,578)		(1,840)		61,769
Other changes to equity	(859)	(859)					(859)
Ending balance at Dec. 31, 2018	3,680,236	3,670,941	251,830	$ 0	(11,783)	9,295	3,423,803		4,961	2,130
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Contributions from noncontrolling interests, net	5,995					5,995
Cumulative Effect of New Accounting Principle in Period of Adoption | ASU No. 2018-02			2,163		(2,163)
Net income attributable to Altice USA, Inc. stockholders	138,936	138,936
Net income attributable to noncontrolling interests	(1,003)					(1,003)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Net Of Tax	(9,697)	(9,697)			(9,697)
Foreign currency translation adjustment, net of income taxes	(1,164)	(1,164)			(1,164)
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	99,077	99,077					99,077
Redeemable equity vested	187,966	187,966					187,966
Adjustments to Additional Paid in Capital, Increase in Carrying Amount of Redeemable Preferred Stock	(166,511)	(166,511)					(166,511)
Class A shares acquired through share repurchase program and retired	(1,686,873)	(1,686,873)					(1,686,146)		(727)
Conversion of Class B to Class A shares, including $2,424 in connection with the Distribution									268	(268)
Stock Issued During Period, Value, New Issues	7,122	7,122					7,099	$ (42)	65
Impact of i24 Acquisition							10,768		5
Ending balance at Dec. 31, 2019	2,279,262	$ 2,269,964	$ 390,766	$ (163,904)	$ (3,250)	9,298	2,039,918		$ 4,572	$ 1,862
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	$ 1,000					$ 1,000
Stock Issued During Period Relating to Acquisition							$ 163,862	$ (163,862)