2013 | 2012 | ||||||||||||||
(dollars in millions) | Gross Amount | Accumulated Amortization | Gross Amount | Accumulated Amortization | |||||||||||
Amortized: | |||||||||||||||
Service portfolios | $ | 2,234 | $ | (1,295 | ) | $ | 2,127 | $ | (1,202 | ) | |||||
Patents and trademarks | 380 | (181 | ) | 412 | (167 | ) | |||||||||
IAE collaboration | 2,273 | — | 1,526 | — | |||||||||||
Customer relationships and other | 12,049 | (2,199 | ) | 11,901 | (1,718 | ) | |||||||||
16,936 | (3,675 | ) | 15,966 | (3,087 | ) | ||||||||||
Unamortized: | |||||||||||||||
Trademarks and other | 2,260 | — | 2,310 | — | |||||||||||
Total | $ | 19,196 | $ | (3,675 | ) | $ | 18,276 | $ | (3,087 | ) | |||||