Note 8. Accounts, Notes and Other Receivables
| December 31, | |||||||
| 2013 | 2012 | ||||||
| Trade | $ | 7,530 | $ | 6,940 | |||
| Other | 646 | 737 | |||||
| 8,176 | 7,677 | ||||||
| Less - Allowance for doubtful accounts | (247) | (248) | |||||
| $ | 7,929 | $ | 7,429 | ||||
Trade Receivables includes $1,609 and $1,495 million of unbilled balances under long-term contracts as of December 31, 2013 and December 31, 2012, respectively. These amounts are billed in accordance with the terms of customer contracts to which they relate.