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Debt - Additional Information (Detail) - USD ($) | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2020 | Dec. 02, 2020 | Oct. 28, 2020 | May 01, 2020 | Mar. 31, 2020
JPMorgan Chase Bank, N.A. [Member] | Revolving Credit Facility [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% |  |  |  |
Fee for outstanding letters of credit | 0.75% |  |  |  |
Debt instrument, covenant description | Under the new revolving credit facility, the Company covenants to maintain a maximum funded debt to EBITDA (as defined in the agreement) ratio of 3.5 to 1.0 and a minimum earnings before interest expense and income taxes to interest ratio 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 maximum funded debt to EBITDA ratio of greater than 2.0 to 1.0. The Company was in compliance with all such provisions as of December 31, 2020. |  |  |  |
Maximum funded debt to EBITDA ratio | 350.00% |  |  |  |
Minimum earnings before interest expense and income taxes to interest ratio | 400.00% |  |  |  |
Percentage of net income to be paid as dividend if EBITDA ratio is greater than 2.0 to 1 | 25.00% |  |  |  |
JPMorgan Chase Bank, N.A. [Member] | Revolving Credit Facility [Member] | Dividend Payment Covenant [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maximum funded debt to EBITDA ratio | 200.00% |  |  |  |
JPMorgan Chase Bank, N.A. [Member] | Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, basis spread on variable rate | 1.75% |  |  |  |
JPMorgan Chase Bank, N.A. [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit |  | $ 7,000,000 |  |  |
HSBC Bank USA [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit |  |  | $ 15,000,000 | $ 14,000,000 |
HSBC Bank USA [Member] | Revolving Credit Facility [Member] | Maximum [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Fee for outstanding letters of credit | 0.85% |  |  |  |
HSBC Bank USA [Member] | Revolving Credit Facility [Member] | Minimum [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Fee for outstanding letters of credit | 0.75% |  |  |  |
JP Morgan Chase Bank, N.A. and HSBC Bank USA, N.A. [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of credit |  |  |  |  | $ 21,672,000
JP Morgan Chase Bank, N.A. and HSBC Bank USA, N.A. [Member] | Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Availability under the line of credit | $ 15,000,000 |  |  |  |
JP Morgan Chase Bank, N.A. and HSBC Bank USA, N.A. [Member] | Letter of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Availability under the line of credit | $ 4,900,000 |  |  |  |

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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 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://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 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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