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Cash and Cash Equivalents (Tables) | 12 Months Ended
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Dec. 31, 2011
Cash and Cash Equivalents |
Summary of cash and cash equivalents |
| December 31, |
|  | 2010 |  | 2011 |
|  | $000 |  | $000 |
Cash |  | 429 |  | 4,555 |
Investments with original maturity of less than three months at the time of purchase |  | 29,066 |  | 19,894 |
Total cash and cash equivalents |  | 29,495 |  | 24,449 |

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- Definition Tabular disclosure of the components of cash and cash equivalents. + References No definition available. + Details
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