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Segment Information - Net Sales by Product Line (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2017 | Mar. 31, 2016 | Mar. 31, 2015
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales | $ 25,624 | $ 22,654 | $ 21,126 | $ 22,365 | $ 22,301 | $ 17,323 | $ 22,798 | $ 27,617 | $ 91,769 | $ 90,039 | $ 135,169
Heat transfer equipment [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales |  |  |  |  |  |  |  |  | 27,616 | 31,479 | 58,224
Vacuum equipment [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales |  |  |  |  |  |  |  |  | 29,672 | 28,323 | 28,698
All other [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales |  |  |  |  |  |  |  |  | $ 34,481 | $ 30,237 | $ 48,247

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- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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