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Other long term obligations (Tables) | 12 Months Ended
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Mar. 31, 2013
Other Liabilities Disclosure [Abstract] |
Schedule of other long term obligations | Other long term obligations are as follows:
|  | March 31, 2013 |  |  | March 31, 2012 |
Liabilities related to equipment leases |  | $ | 104 |  |  | $ | 3,169 |
Deferred lease inducements (note 18(b)) |  | 440 |  |  | 547 |
Asset retirement obligation (note 18(c)) |  | 477 |  |  | 434 |
Senior executive stock option plan (note 24(c)) |  | 925 |  |  | 1,322 |
Restricted share unit plan (note 24(e)) |  | 2,768 |  |  | 3,170 |
Directors' deferred stock unit plan (note 24(f)) |  | 3,106 |  |  | 2,284 |
|  | $ | 7,820 |  |  | $ | 10,926 |
Less current portion of: |  |  |  |
Restricted share unit plan (note 24(e)) |  | (719 | ) |  | (2,066 | )
Directors' deferred share unit plan (note 24(f)) |  | (355 | ) |  | — |
|  | $ | 6,746 |  |  | $ | 8,860 |
Schedule of changes in deferred lease inducements |
|  | March 31, 2013 |  |  | March 31, 2012 |
Balance, beginning of year |  | $ | 547 |  |  | $ | 654 |
Amortization of deferred lease inducements |  | (107 | ) |  | (107 | )
Balance, end of year |  | $ | 440 |  |  | $ | 547 |
Schedule of changes in asset retirement obligation | The following table presents a continuity of the liability for the asset retirement obligation:
|  | March 31, 2013 |  |  | March 31, 2012 |
Balance, beginning of year |  | $ | 434 |  |  | $ | 395 |
Accretion expense |  | 43 |  |  | 39 |
Balance, end of year |  | $ | 477 |  |  | $ | 434 |

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- Definition Schedule of Lease Incentives [Table Text Block] + References No definition available. + Details
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- Definition Schedule of Other Liabilities [Table Text Block] + References No definition available. + Details
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- Details
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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859 + Details
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