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Employee Benefit Plans (Details 14) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Mar. 31, 2013 | Mar. 31, 2012 | Mar. 31, 2011
Decrease in accumulated other comprehensive (income) loss, net of income tax |  |  |
Total | $ (92) | $ 3,223 | $ 707
Other postretirement benefit plans [Member] |  |  |
Decrease in accumulated other comprehensive (income) loss, net of income tax |  |  |
Net actuarial loss arising during the year | 61 | 43 |
Amortization of actuarial loss | (28) | (24) |
Amortization of prior service cost | 107 | 107 |
Total | $ 140 | $ 126 |

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