Segments and Geographic Information - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Total assets	$ 7,861,206	$ 4,917,058
Cash and cash equivalents	617,962	729,321	$ 616,434	$ 346,320
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	7,153,000	4,128,800
Operating Segments [Member] | Wireless [Member]
Segment Reporting Information [Line Items]
Total assets	2,252,700	2,372,800
Operating Segments [Member] | Enterprise [Member]
Segment Reporting Information [Line Items]
Total assets	1,404,100	1,403,400
Operating Segments [Member] | Broadband [Member]
Segment Reporting Information [Line Items]
Total assets	327,600	352,600
Operating Segments [Member] | BNS [Member]
Segment Reporting Information [Line Items]
Total assets	3,168,600
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Cash and cash equivalents	618,000	729,300
Deferred income tax assets	$ 90,200	$ 59,000