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Employee Benefit Plans - Summary of Increase/Decrease in Accumulated Other Comprehensive Loss, Net of Income Tax (Detail) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
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Mar. 31, 2014 | Mar. 31, 2013 | Mar. 31, 2012
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total | $ (2,275) | $ (92) | $ 3,223
Pension Plans, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net actuarial (gain) loss arising during the year | (1,692) | 424 |
Amortization of actuarial loss | (647) | (653) |
Amortization of prior service cost | (3) | (3) |
Total | (2,342) | (232) |
Other Postretirement Benefit Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Net actuarial (gain) loss arising during the year | (10) | 61 |
Amortization of actuarial loss | (30) | (28) |
Amortization of prior service cost | 107 | 107 |
Total | $ 67 | $ 140 |

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- Definition Net of tax amount of the income statement impact of the reclassification adjustment for the amortization of actuarial losses recognized as a component of net period benefit cost. + References No definition available. + Details
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- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580 + Details
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- Definition Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580 + Details
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- Definition Amount after tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e689-108580 + Details
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