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Employee Benefit Plans - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Mar. 31, 2012
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employee's years of service and average earnings | Five highest consecutive calendar years of compensation in the ten-year period preceding retirement |  |
Accumulated benefit obligation | $ 28,254 | $ 27,809 |
Employer contribution description | Matching contributions equal to 100 percent of the first 3% of an employee's salary deferral and 50% of the next two percent of an employee's salary deferral |  |
Contribution equal to employee salary deferral | 100.00% |  |
Contribution next to employee salary deferral | 3.00% |  |
Contribution for additional employee salary deferral | 50.00% |  |
Contribution additional next to employee salary deferral | 2.00% |  |
Share of the medical premium cost for family coverage | 4 |  |
Share of the medical premium cost for single coverage | 2 |  |
Share of the medical premium both family and single coverage for regular retirees | 1 |  |
Medical care cost trend rate | 5.00% |  |
Medical care trend year | 2020 |  |
Medical care cost trend rate decrements | 0.50% |  |
Current portion of accrued postretirement benefit obligation | 98 | 107 |
Employee stock ownership plan, shares | 252 | 279 |
Company contributions to the ESOP | 0 | 0 | 0
Stop loss coverage per employee for claims | 100 |  |
Maximum aggregate stop loss coverage | 1,000 |  |
Total plan amount | 3,707 |  |
Self-Insured medical plan liability | 221 |  |
Defined Contribution Pension [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to defined contribution plan | 257 | 204 | 161
Pension Plans, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Estimated net actuarial loss for pension plan | 580 |  |
Estimated prior service cost for pension plan | 4 |  |
Pension expense | 213 | 248 | (312)
Weighted average discount rate used to develop net postretirement benefit cost | 4.28% | 4.76% | 5.63%
Supplemental Executive Retirement Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension expense | 70 | 24 | 21
Pension expense related liability | 298 | 254 |
Current portion of the related liability included in accrued compensation | 26 | 27 |
401K Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to defined contribution plan | 831 | 753 | 457
Other Postretirement Benefit Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Estimated net actuarial loss for pension plan | 40 |  |
Estimated prior service cost for pension plan | (106) |  |
Pension expense | $ (87) | $ (83) | $ (84)
Weighted average discount rate used to develop net postretirement benefit cost | 3.26% | 3.96% | 4.69%

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- Definition Current portion of the accrued postretirement liability recorded in the consolidated balance sheet. + References No definition available. + Details
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- Definition Aggregate annual stop loss coverage amount per employee for claims incurred. + References No definition available. + Details
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- Definition Aggregate annual stop loss coverage for the entire medical plan. + References No definition available. + Details
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- Definition Average earnings description for calculation of benefits. + References No definition available. + Details
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- Definition Company's share of the medical premium cost for early retirees for family coverage under the other postretirement plan. + References No definition available. + Details
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- Definition Company's share of the medical premium cost for early retirees for single coverage under the other postretirement plan. + References No definition available. + Details
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- Definition Company's share of the medical premium cost for regular retirees for coverage under the other postretirement plan. + References No definition available. + Details
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- Definition The employer matching contribution percentage on the 2% employee salary deferral after the first 3% employee salary deferral. + References No definition available. + Details
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- Definition Annual decrement percentage in the defined benefit plan health care cost trend rate used to reach the ultimate health care cost trend rate. + References No definition available. + Details
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- Definition Percentage of employee's first 3% salary deferral for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition The employee deferral percentage that receives a 50% employer matching contribution. + References No definition available. + Details
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- Definition The employee salary deferral that receives 100% matching company contribution. + References No definition available. + Details
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- Definition Description of employer matching contributions to the 401K plan. + References No definition available. + Details
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- Definition Employee stock ownership plan outstanding. + References No definition available. + Details
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- Definition Employer contribution to employee stock ownership plan. + References No definition available. + Details
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- Definition The liability recognized in the balance sheet that is associated with the self insured medical plan. + References No definition available. + Details
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- Definition Stop loss coverage amount per employee for each specific claim incurred. + References No definition available. + Details
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- Definition For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503844 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The interest rate used to adjust for the time value of money. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Details
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- Definition Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position. + References No definition available. + Details
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- Definition Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position. + References No definition available. + Details
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The ultimate trend rate for health care costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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- Definition For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Current Liabilities -URI http://asc.fasb.org/extlink&oid=6509677 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -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 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919 + Details
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- Definition This represents the entire liability recognized in the balance sheet that is associated with the defined benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2417-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2410-114920 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919 + Details
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