Employee Benefit Plans (Details 4) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 0	$ 0	$ 0
Interest cost		1,382	1,733	1,751
Return on assets (expected)		(248)	(895)	(795)
Amortization of net actuarial loss (gain)	[1]	1,012	552	544
Settlement charge (benefit)		9,236	0	0
Adjustments		0	0	0
Foreign currency		0	0	0
Net periodic pension cost		11,382	1,390	1,500
Non-U.S. Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost		615	664	703
Interest cost		393	486	614
Return on assets (expected)		(266)	(323)	(275)
Amortization of net actuarial loss (gain)	[1]	0	(78)	(70)
Settlement charge (benefit)		(3,571)	0	(178)
Adjustments		0	0	(1,849)
Foreign currency		0	0	(31)
Net periodic pension cost		$ (2,829)	$ 749	$ (1,086)

[1] ARRIS uses the allowable 10% corridor approach to determine the amount of gains/losses subject to amortization in pension cost. Gains/losses are amortized on a straight-line basis over the average future service of members expected to receive benefits