CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 77,396	$ 33,739	$ 138,608	$ (193,214)
Defined benefit pension plans:
Unrecognized actuarial gain (loss)	(15,860)	9,602	(19,508)	13,794
Applicable income taxes	4,298	(2,592)	5,287	(3,723)
Unrecognized actuarial gain (loss) arising during period, net of income taxes	(11,562)	7,010	(14,221)	10,071
Settlement loss included in other expense, net	1,091	65	1,629	929
Applicable income taxes	(295)	(18)	(441)	(252)
Settlement loss included in other expense, net, net of income taxes	796	47	1,188	677
Foreign currency translation adjustment	(385)	437	(965)	1,351
Applicable income taxes	105	(27)	261	(365)
Foreign currency translation adjustment, net	(280)	410	(704)	986
Other comprehensive income (loss)	(11,046)	7,467	(13,737)	11,734
Comprehensive income (loss)	66,350	41,206	124,871	(181,480)
Comprehensive income attributable to noncontrolling interests	(157)	(1,186)	(1)	(1,039)
Comprehensive income (loss) attributable to Altice USA, Inc. stockholders	$ 66,193	$ 40,020	$ 124,870	$ (182,519)

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