Intangible Assets

6 Months Ended

Jun. 30, 2015

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

7. Intangible Assets

Intangible assets consisted of the following:

(In millions) June 30, 2015	Gross Carrying Amount		Accumulated Amortization		Net Book Value
Customer related intangible assets	$	2,155	$	860	$	1,295
Acquired software and technology		493		388		105
Trade names		120		50		70
Capitalized software development costs		557		199		358
Purchased software		259		147		112
Total	$	3,584	$	1,644	$	1,940

(In millions) December 31, 2014	Gross Carrying Amount		Accumulated Amortization		Net Book Value
Customer related intangible assets	$	2,155	$	797	$	1,358
Acquired software and technology		493		356		137
Trade names		120		46		74
Capitalized software development costs		574		240		334
Purchased software		234		134		100
Total	$	3,576	$	1,573	$	2,003

The Company estimates that annual amortization expense with respect to acquired intangible assets, which include customer related intangible assets, acquired software and technology, and trade names, will be approximately $190 million in 2015, $150 million in 2016, $140 million in each of 2017 and 2018, and $130 million in 2019. Annual amortization expense in 2015 with respect to capitalized and purchased software is estimated to approximate $115 million.