Reconciliation of Numerators and Denominators of Basic and Diluted Earnings Per Share Computations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Basic:
Net income (loss) attributable to ARRIS International plc		$ 35,754	$ 30,336	$ 22,154	$ (8,762)
Weighted average shares outstanding		184,216	186,803	184,376	188,291
Basic earnings (loss) per share	[1]	$ 0.19	$ 0.16	$ 0.12	$ (0.05)
Diluted:
Net income (loss) attributable to ARRIS International plc		$ 35,754	$ 30,336	$ 22,154	$ (8,762)
Weighted average shares outstanding		184,216	186,803	184,376	188,291
Net effect of dilutive equity awards		1,453	2,199	1,912
Total		185,669	189,002	186,288	188,291
Diluted earnings (loss) per share	[1]	$ 0.19	$ 0.16	$ 0.12	$ (0.05)

[1] Calculated based on net income (loss) attributable to stockholders of ARRIS International plc