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Interest expense | 12 Months Ended
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Mar. 31, 2012
Interest Expense [Abstract] |
Interest expense | 19. Interest expense
|  | 2012 |  |  |  |  | 2011 |  |  |  |  | 2010 |
Year ended March 31, |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest on 8 3/4% senior notes and swaps |  |  | $– |  |  |  |  |  | $1,238 |  |  |  |  |  | $19,041 |
Interest on capital lease obligations |  |  | 445 |  |  |  |  |  | 689 |  |  |  |  |  | 1,032 |
Amortization of deferred financing costs |  |  | 1,591 |  |  |  |  |  | 1,609 |  |  |  |  |  | 3,348 |
Interest on credit facilities |  |  | 7,430 |  |  |  |  |  | 5,361 |  |  |  |  |  | 2,375 |
Interest on Series 1 Debentures |  |  | 20,531 |  |  |  |  |  | 20,132 |  |  |  |  |  | – |
Interest on long term debt |  |  | $29,997 |  |  |  |  |  | $29,029 |  |  |  |  |  | $25,796 |
Other interest |  |  | 328 |  |  |  |  |  | 962 |  |  |  |  |  | 284 |
|  |  | $30,325 |  |  |  |  |  | $29,991 |  |  |  |  |  | $26,080 |

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