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Employee Benefit Plans (Details 13) (Other postretirement benefit plans [Member], USD $) In Thousands, unless otherwise specified | Mar. 31, 2013 | Mar. 31, 2012 | Mar. 31, 2011
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Other postretirement benefit plans [Member] |  |  |
Amounts recognized in accumulated other comprehensive loss (income), net of income tax, consist of |  |  |
Net actuarial loss | $ 336 | $ 303 |
Prior service cost | (176) | (283) |
Total | $ 160 | $ 20 | $ (106)

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- Definition Defined benefit plan accumulated other comprehensive income net actuarial loss after tax. + References No definition available. + Details
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- Definition After tax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s). + References No definition available. + Details
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- Definition Amount related to after tax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost. + References No definition available. + Details
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