XML 24 R12.htm IDEA: XBRL DOCUMENT v3.6.0.2
Property, Plant and Equipment
 12 Months Ended
Dec. 31, 2016
Property, Plant and Equipment [Abstract]  
Property, Plant and Equipment
Property, Plant and Equipment
Net property, plant and equipment is composed of the following:
 
Depreciable
Lives
 
As of December 31,
 
 
2016
 
2015
 
 
 
(Dollars in millions)
Property, plant and equipment:
 
 
 
 
 
Land
N/A
 
$
348

 
349

Fiber, conduit and other outside plant(1)
15-45 years
 
5,980

 
5,362

Central office and other network electronics(2)
4-10 years
 
3,855

 
3,614

Support assets(3)
5-30 years
 
2,633

 
2,584

Construction in progress(4)
N/A
 
431

 
273

Gross property, plant and equipment
 
 
13,247

 
12,182

Accumulated depreciation
 
 
(5,602
)
 
(4,808
)
Net property, plant and equipment
 
 
$
7,645

 
7,374

_______________________________________________________________________________
(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, 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.
We recorded depreciation expense of $924 million, $986 million and $1.048 billion for the years ended December 31, 2016, 2015 and 2014, respectively.
In 2014, we recorded an impairment charge of $17 million in connection with a sale-leaseback transaction involving an office building that we closed in the fourth quarter of 2014. This impairment charge is included in selling, general and administrative expense in our consolidated statement of operations for the year ended December 31, 2014.