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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2012
Accounting Policies [Abstract] |
Schedule of rates of exchange for the U.S. dollar that have been used for the most significant operations | The following rates of exchange for the U.S. dollar have been used for the most significant operations:
Currency |  | Opening Rate 2012 |  | Closing Rate 2012 |  | Opening Rate 2011 |  | Closing Rate 2011
Swedish kronor |  | 6.8645 |  |  | 6.4973 |  |  | 6.7030 |  |  | 6.8645 |
British pound |  | 0.6434 |  |  | 0.6154 |  |  | 0.6420 |  |  | 0.6434 |
Canadian dollar |  | 1.0193 |  |  | 0.9955 |  |  | 0.9981 |  |  | 1.0193 |

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- Definition Tabular disclosure of opening and closing rates of exchange that have been used for the most significant operations. + References No definition available. + Details
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