MCKESSON CORP | 2013 | FY | 3

Goodwill and Intangible Assets, Net
Changes in the carrying amount of goodwill were as follows:
(In millions)
Distribution
Solutions
 
Technology
Solutions
 
Total
Balance, March 31, 2011
$
2,662

 
$
1,702

 
$
4,364

Goodwill acquired
511

 
151

 
662

Acquisition accounting and other adjustments
20

 
—

 
20

Foreign currency translation adjustments
(3
)
 
(11
)
 
(14
)
Balance, March 31, 2012
$
3,190

 
$
1,842

 
$
5,032

Goodwill acquired
1,228

 
193

 
1,421

Impairment
—

 
(36
)
 
(36
)
Acquisition accounting and other adjustments
6

 
(1
)
 
5

Foreign currency translation adjustments
(11
)
 
(6
)
 
(17
)
Balance, March 31, 2013
$
4,413

 
$
1,992

 
$
6,405


As of March 31, 2013, the accumulated goodwill impairment losses were $36 million in our Technology Solutions segment.
Information regarding intangible assets is as follows:
 
March 31, 2013
 
March 31, 2012
(Dollars in millions)
Weighted
Average
Remaining
Amortization
Period
(Years)
 
Gross
Carrying
Amount
 
Accumulated
Amortization
 
Net
Carrying
Amount
 
Gross
Carrying
Amount
 
Accumulated
Amortization
 
Net
Carrying
Amount
Customer lists
8
 
$
1,761

 
$
(672
)
 
$
1,089

 
$
1,081

 
$
(554
)
 
$
527

Service agreements
17
 
1,018

 
(114
)
 
904

 
1,022

 
(52
)
 
970

Trademarks and trade names
16
 
208

 
(46
)
 
162

 
192

 
(38
)
 
154

Technology
4
 
271

 
(207
)
 
64

 
244

 
(190
)
 
54

Other
6
 
89

 
(38
)
 
51

 
76

 
(31
)
 
45

Total
 
 
$
3,347

 
$
(1,077
)
 
$
2,270

 
$
2,615

 
$
(865
)
 
$
1,750

Amortization expense of intangible assets was $215 million, $191 million and $132 million for 2013, 2012 and 2011. Estimated annual amortization expense of intangible assets is as follows: $284 million, $262 million, $228 million, $202 million and $184 million for 2014 through 2018, and $1,110 million thereafter. All intangible assets were subject to amortization as of March 31, 2013 and 2012.

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