PPG INDUSTRIES INC | 2013 | FY | 3

Goodwill and Other Identifiable Intangible Assets
 
The change in the carrying amount of goodwill attributable to each reportable business segment for the years ended December 31, 2013 and 2012 was as follows:
(Millions)
Perform-ance
Coatings
Industrial
Coatings
Architectural
Coatings—
EMEA
Optical
and
Specialty
Materials
Glass
Commodity
Chemicals
Total
Balance, Jan. 1, 2012
$
1,139

$
484

$
933

$
48

$
50

$
6

$
2,660

Goodwill from acquisitions
22

18

18

—

—

—

58

Foreign currency translation
12

10

19

—

2

—

43

Balance, Dec. 31, 2012
$
1,173

$
512

$
970

$
48

$
52

$
6

$
2,761

Goodwill from acquisitions
235

4

—

—

—

—

239

Goodwill reduction due to Separation (See Note 22)
—

—

—

—

—

(6
)
(6
)
Foreign currency translation
(25
)
9

28

2

—

—

14

Balance, Dec. 31, 2013
$
1,383

$
525

$
998

$
50

$
52

$
—

$
3,008



The carrying amount of acquired trademarks with indefinite lives as of December 31, 2013 and 2012 totaled $499 million and $324 million, respectively.
 
The Company’s identifiable intangible assets with finite lives are being amortized over their estimated useful lives and are detailed below.
 
Dec. 31, 2013
 
Dec. 31, 2012
(Millions)
Gross
Carrying
Amount
 
Accumulated
Amortization
 
Net
 
Gross
Carrying
Amount
 
Accumulated
Amortization
 
Net
Acquired 
technology
$
522

 
$
(372
)
 
$
150

 
$
516

 
$
(342
)
 
$
174

Customer-related intangibles
1,177

 
(557
)
 
620

 
1,010

 
(491
)
 
519

Tradenames
127

 
(61
)
 
66

 
120

 
(57
)
 
63

Other
30

 
(26
)
 
4

 
34

 
(29
)
 
5

Balance
$
1,856

 
$
(1,016
)
 
$
840

 
$
1,680

 
$
(919
)
 
$
761



Aggregate amortization expense was $119 million, $109 million and $120 million in 2013, 2012 and 2011, respectively. The estimated future amortization expense of identifiable intangible assets per year is approximately $120 million during 2014 and 2015, approximately $101 million during 2016, approximately $93 million in 2017 and approximately $91 million in 2018.

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