CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 107,286	$ 66,124	$ 8,961
Available-for-sale securities:
Unrealized gain (loss) on available-for-sale securities, net of tax of $0, $(288) and $6 in 2018, 2017 and 2016, respectively		471	(11)
Reclassification adjustments recognized in net income, net of tax of $(2), $(33) and $(9) in 2018, 2017 and 2016, respectively	6	54	15
Net change in available-for-sale	6	525	4
Derivative instruments:
Unrealized gain on derivative instruments, net of tax of $(30), $(1,797) and $(472) in 2018, 2017 and 2016, respectively	1,091	3,790	1,631
Reclassification adjustments recognized in net income, net of tax of $77, $(535) and $(1,691) in 2018, 2017 and 2016, respectively	(2,774)	1,128	5,821
Net change in derivative instruments	(1,683)	4,918	7,452
Pension obligations:
Unrealized gain (loss) on pension obligations, net of tax of $(825), $1,391 and $1,425 in 2018, 2017 and 2016, respectively	2,338	(2,487)	(2,934)
Reclassification adjustments recognized in net income, net of tax of $(2,209), $(170) and $(155) in 2018, 2017 and 2016, respectively	6,263	304	319
Net change in pension obligations	8,601	(2,183)	(2,615)
Cumulative translation adjustments	(24,110)	(2,050)	11,096
Other comprehensive (loss) income, net of tax	(17,186)	1,210	15,937
Comprehensive income	90,100	67,334	24,898
Comprehensive loss attributable to noncontrolling interest	(6,411)	(25,954)	(9,127)
Comprehensive income attributable to ARRIS International plc	$ 96,511	$ 93,288	$ 34,025