Intangible Assets, Net (Tables)

12 Months Ended

Dec. 31, 2016

Intangible Assets, Net [Abstract]

Gross And Net Carrying Amounts For Each Major Class Of Intangible Assets

	As of December 31, 2016						As of December 31, 2015
	Gross carrying		Accumulated		Net book		Gross carrying		Accumulated		Net book
	amount		amortization		value		amount		amortization		value
	(in thousands)
Current contract intangibles	$	4,141,968	$	(1,401,025)	$	2,740,943	$	3,904,864	$	(1,118,493)	$	2,786,371
Network location intangibles		1,515,348		(599,367)		915,981		1,446,293		(497,251)		949,042
Intangible assets, net	$	5,657,316	$	(2,000,392)	$	3,656,924	$	5,351,157	$	(1,615,744)	$	3,735,413

Estimated Future Amortization Expense

For the year ended December 31,	(in thousands)
2017	$	376,482
2018		376,393
2019		376,095
2020		375,253
2021		342,972