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The Company and Its Accounting Policies - Summary of Costs and Estimated Earnings on Contracts (Detail) - USD ($) $ in Thousands | Mar. 31, 2018 | Mar. 31, 2017
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Accounting Policies [Abstract] |  |
Costs incurred since inception on contracts in progress | $ 43,806 | $ 44,263
Estimated earnings since inception on contracts in progress | 8,123 | 4,348
Costs and estimated earnings | 51,929 | 48,611
Less billings to date | 67,172 | 52,410
Net under (over) billings | $ (15,243) | $ (3,799)

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- Definition Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method that are expected to be realized within one year or one operating cycle, whichever is longer, from the reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 35 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57788-111642 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 35 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57807-111642 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 35 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68068069&loc=d3e57795-111642 + Details
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