Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			$ 3,184,034
Other comprehensive income (loss), net of tax	$ (4,005)	$ 6,613	(13,207)	$ 5,547
Balance	2,953,510		2,953,510
Available-for-sale securities
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			662	137
Other comprehensive income before reclassifications			0	260
Amounts reclassified from accumulated other comprehensive income (loss)			(662)	68
Other comprehensive income (loss), net of tax			(662)	328
Balance	0	465	0	465
Derivative instruments
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			5,589	671
Other comprehensive income before reclassifications			15,051	(240)
Amounts reclassified from accumulated other comprehensive income (loss)			(990)	1,086
Other comprehensive income (loss), net of tax			14,061	846
Balance	19,650	1,517	19,650	1,517
Pension obligations
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			(8,993)	(6,810)
Other comprehensive income before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income (loss)			28	9
Other comprehensive income (loss), net of tax			28	9
Balance	(8,965)	(6,801)	(8,965)	(6,801)
Cumulative translation adjustments
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			7,243	9,281
Other comprehensive income before reclassifications			(26,619)	4,321
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Other comprehensive income (loss), net of tax			(26,619)	4,321
Balance	(19,376)	13,602	(19,376)	13,602
Total accumulated other comprehensive income (Loss)
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			4,501	3,279
Other comprehensive income before reclassifications			(11,568)	4,341
Amounts reclassified from accumulated other comprehensive income (loss)			(1,624)	1,163
Other comprehensive income (loss), net of tax			(13,192)	5,504
Balance	(8,691)	8,783	(8,691)	8,783
Less AOCI attributable to Non-controlling Interest
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			51	12
Other comprehensive income before reclassifications			(15)	43
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Other comprehensive income (loss), net of tax			(15)	43
Balance	36	55	36	55
Total ARRIS International plc AOCI
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance			4,552	3,291
Other comprehensive income before reclassifications			(11,583)	4,384
Amounts reclassified from accumulated other comprehensive income (loss)			(1,624)	1,163
Other comprehensive income (loss), net of tax			(13,207)	5,547
Balance	$ (8,655)	$ 8,838	$ (8,655)	$ 8,838