Summary of Net Intangible Assets and Goodwill by Reportable Segment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Goodwill	$ 2,278,512	$ 2,016,169
Intangible assets, net	1,771,362	1,677,178
CPE
Segment Reporting Information [Line Items]
Goodwill	1,386,680	1,391,171
Intangible assets, net	807,314	1,064,692
N&C
Segment Reporting Information [Line Items]
Goodwill	573,798	624,998
Intangible assets, net	501,998	$ 612,486
Enterprise
Segment Reporting Information [Line Items]
Goodwill	318,034
Intangible assets, net	$ 462,050