XML 47 R33.htm IDEA: XBRL DOCUMENT v3.3.1.900
Property, Plant and Equipment (Tables)
 12 Months Ended
Dec. 31, 2015
Property, Plant and Equipment [Abstract]  
Schedule of net property, plant and equipment
Net property, plant and equipment is composed of the following:
 
Depreciable
Lives
 
As of December 31,
 
 
2015
 
2014
 
 
 
(Dollars in millions)
Land
n/a
 
$
571

 
575

Fiber, conduit and other outside plant (1)
15-45
 
16,166

 
15,151

Central office and other network electronics (2)
3-10
 
14,144

 
13,248

Support assets (3)
3-30
 
7,000

 
6,578

Construction in progress (4)
n/a
 
904

 
1,166

Gross property, plant and equipment
 
 
38,785

 
36,718

Accumulated depreciation
 
 
(20,716
)
 
(18,285
)
Net property, plant and equipment
 
 
$
18,069

 
18,433

_______________________________________________________________________________
(1) 
Fiber, conduit and other outside plant consists of fiber and metallic cable, conduit, poles and other supporting structures.
(2) 
Central office and other network electronics consists of circuit and packet switches, routers, transmission electronics and electronics providing service to customers.
(3) 
Support assets consist of buildings, data centers, computers and other administrative and support equipment.
(4) 
Construction in progress includes inventory held for construction and property of the aforementioned categories that has not been placed in service as it is still under construction.
Schedule of changes to asset retirement obligations
The following table provides asset retirement obligation activity:
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
(Dollars in millions)
Balance at beginning of year
$
107

 
106

 
106

Accretion expense
7

 
7

 
7

Liabilities incurred
—

 
6

 
—

Liabilities settled
(2
)
 
(2
)
 
(4
)
Change in estimate
(21
)
 
(10
)
 
(3
)
Balance at end of year
$
91

 
107

 
106