Revenue from Contracts with Customers (Details 1) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		$ 1,651,248	$ 1,728,524	$ 4,955,498	$ 4,875,799
UNITED STATES
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		983,377	1,131,723	2,869,848	3,211,278
Americas, excluding U.S.
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		302,412		886,123
Asia Pacific
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		100,448		300,058
EMEA
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		265,011		899,469
Non-US
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		667,871		2,085,650
Domestic Operations | UNITED STATES
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		983,377	1,131,723	2,869,848	3,211,278
Operating Segments | CPE
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		941,469	1,174,750	2,824,827	3,385,689
Operating Segments | CPE | UNITED STATES
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		533,410		1,546,338
Operating Segments | CPE | Americas, excluding U.S.
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		206,350		582,564
Operating Segments | CPE | Asia Pacific
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		30,814		82,020
Operating Segments | CPE | EMEA
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		170,895		613,905
Operating Segments | CPE | Non-US
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		408,059		1,278,489
Operating Segments | N&C
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		532,035	556,863	1,619,795	1,498,271
Operating Segments | N&C | UNITED STATES
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		334,591		1,006,903
Operating Segments | N&C | Americas, excluding U.S.
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		97,785		297,665
Operating Segments | N&C | Asia Pacific
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		39,670		135,013
Operating Segments | N&C | EMEA
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		59,989		180,214
Operating Segments | N&C | Non-US
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		197,444		612,892
Operating Segments | Enterprise
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		180,159	$ 0	522,313	$ 0
Operating Segments | Enterprise | UNITED STATES
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		116,691		323,033
Operating Segments | Enterprise | Americas, excluding U.S.
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		(1,723)		5,899
Operating Segments | Enterprise | Asia Pacific
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		29,964		83,065
Operating Segments | Enterprise | EMEA
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		35,227		110,316
Operating Segments | Enterprise | Non-US
International Long-Lived Assets by Geographic Region [Line Items]
Net sales		63,468		199,280
Operating Segments | Other
International Long-Lived Assets by Geographic Region [Line Items]
Net sales	[1]	(2,415)		(11,437)
Operating Segments | Other | UNITED STATES
International Long-Lived Assets by Geographic Region [Line Items]
Net sales	[1]	(1,315)		(6,426)
Operating Segments | Other | Americas, excluding U.S.
International Long-Lived Assets by Geographic Region [Line Items]
Net sales	[1]	0		(5)
Operating Segments | Other | Asia Pacific
International Long-Lived Assets by Geographic Region [Line Items]
Net sales	[1]	0		(40)
Operating Segments | Other | EMEA
International Long-Lived Assets by Geographic Region [Line Items]
Net sales	[1]	(1,100)		(4,966)
Operating Segments | Other | Non-US
International Long-Lived Assets by Geographic Region [Line Items]
Net sales	[1]	$ (1,100)		$ (5,011)

[1] Adjustments include acquisition accounting impacts related to deferred revenue.