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Debt - Additional Information (Detail) - USD ($) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 24, 2014 | Mar. 31, 2018 | Mar. 31, 2017 | Dec. 02, 2015
Debt Instrument [Line Items] |  |  |  |
Short-term borrowings outstanding |  | $ 0 | $ 0 |
Letters of credit outstanding amount |  | 8,233,000 | $ 8,372,000 |
Long-term debt payment requirements over the next five years |  | 0 |  |
Letter of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of credit | $ 5,000,000 |  |  |
Letters of credit outstanding amount |  | $ 995,000 |  |
Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt Instrument, Covenant Compliance |  | The Company was in compliance with all such provisions as of and for the years ended March 31, 2018 and 2017. |  |
Assets book value |  | $ 122,122,000 |  |
Revolving Credit Facility [Member] | Letter of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Availability under the line of credit |  | $ 4,005,000 |  |
Maximum funded debt to EBITDA ratio | 350.00% |  |  |
Annual facility fees | 0.375% |  |  |
Minimum earnings to interest ratio | 400.00% |  |  |
Revolving Credit Facility [Member] | Maximum [Member] | Letter of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fee for outstanding letters of credit | 1.25% |  |  |
Revolving Credit Facility [Member] | Minimum [Member] | Letter of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fee for outstanding letters of credit | 0.75% |  |  |
Revolving Credit Facility [Member] | Prime Rate [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Bank's prime rate |  | 4.75% | 4.00% |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of credit |  |  |  | $ 25,000,000
Maximum limit of credit facility |  |  |  | $ 50,000,000
Term period of agreement |  | 5 years |  |
Interest rate description |  | interest at either: (i) a rate equal to the bank's prime rate; or (ii) a rate equal to LIBOR plus a margin |  |
Fix rate to reduce fee on outstanding |  | 0.40% |  |
Availability under the line of credit |  | $ 20,331,000 |  |
Debt instrument, covenant description |  | Under the revolving credit facility, the Company covenants to maintain a maximum funded debt to EBITDA ratio, as defined in such credit facility, of 3.5 to 1.0 and a minimum earnings before interest expense and income taxes ("EBIT") to interest ratio, as defined in such credit facility, of 4.0 to 1.0. The agreement also provides that the Company is permitted to pay dividends without limitation if it maintains a maximum funded debt to EBITDA ratio equal to or less than 2.0 to 1.0 and permits the Company to pay dividends in an amount equal to 25% of net income if it maintains a funded debt to EBITDA ratio of greater than 2.0 to 1.0. |  |
Percentage of net income to be paid as dividend if EBITDA ratio is greater than 2.0 to 1 |  | 25.00% |  |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Unused commitment fee for borrowing |  | 0.30% |  |
Fee for outstanding letters of credit |  | 1.20% |  |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] | Maximum [Member] | Dividend Payment Covenant [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum funded debt to EBITDA ratio |  | 200.00% |  |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] | Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Unused commitment fee for borrowing |  | 0.20% |  |
Fee for outstanding letters of credit |  | 0.70% |  |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, basis spread on variable rate |  | 1.75% |  |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, basis spread on variable rate |  | 0.95% |  |
JPMorgan Chase Bank, N.A. [Member] | 2015 Credit Facility Agreement [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letters of credit outstanding amount |  | $ 4,669,000 |  |
Bank of America, N.A. [Member] | 2015 Credit Facility Agreement [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letters of credit outstanding amount |  | $ 2,569,000 |  |

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- Definition Amount of assets pledged to secure a debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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(a)(16)) -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(16)) -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 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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