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Debt - Additional Information (Detail) - USD ($) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 02, 2020 | Oct. 08, 2020 | May 01, 2020
Debt Instrument [Line Items] |  |  |  |  |
Short-term borrowings outstanding | $ 0 | $ 0 |  |  |
Letters of credit outstanding amount | 11,567,000 | 13,328,000 |  |  |
Long-term debt payment requirements over the next five years | 0 |  |  |  |
HSBC Bank USA [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit |  | $ 10,000,000 |  | $ 15,000,000 | $ 14,000,000
Letters of credit outstanding amount | $ 6,151,000 |  |  |  |
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, 2021 and 2020. |  |  |  |
Assets book value | $ 117,360,000 |  |  |  |
Revolving Credit Facility [Member] | 2015 Credit Facility Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Fee for outstanding letters of credit | 0.75% |  |  |  |
Availability under the line of credit | $ 16,584,000 |  |  |  |
Revolving Credit Facility [Member] | Prime Rate [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Interest rate | 3.25% | 3.25% |  |  |
Revolving Credit Facility [Member] | JPMorgan Chase Bank, N.A. [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit |  |  | $ 22,000,000 |  |
Maximum limit of credit facility |  |  | 37,000,000 |  |
Term period of agreement | 1 year |  |  |  |
Interest rate description | interest at either: (i) a rate equal to the bank's prime rate; or (ii) a rate equal to LIBOR plus 1.75% |  |  |  |
Debt instrument description of variable rate basis | LIBOR plus 1.75% |  |  |  |
Unused commitment fee for borrowing | 0.375% |  |  |  |
Debt instrument, covenant description | Under the revolving credit facility, the Company covenants to maintain a maximum funded debt to earnings before interest expense, income taxes, depreciation and amortization ("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] | JPMorgan Chase Bank, N.A. [Member] | Dividend Payment Covenant [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maximum funded debt to EBITDA ratio | 200.00% |  |  |  |
Revolving Credit Facility [Member] | JPMorgan Chase Bank, N.A. [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, basis spread on variable rate | 1.75% |  |  |  |
Revolving Credit Facility [Member] | HSBC Bank USA [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, basis spread on variable rate |  | 3.00% |  |  |
Availability under the line of credit | $ 8,849,000 |  |  |  |
Annual facility fee |  | $ 5,000 |  |  |
Revolving Credit Facility [Member] | HSBC Bank USA [Member] | Maximum [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Fee for outstanding letters of credit |  | 0.85% |  |  |
Revolving Credit Facility [Member] | HSBC Bank USA [Member] | Minimum [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Fee for outstanding letters of credit |  | 0.75% |  |  |
Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit |  |  | $ 7,000,000 |  |
JPMorgan Chase Bank, N.A. [Member] | 2015 Credit Facility Agreement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Letters of credit outstanding amount | $ 5,416,000 |  |  |  |

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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://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 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://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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=120398452&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -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=120391452&loc=d3e13212-122682 + Details
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