Segment Information - Net Sales by Product Line (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]
Net sales	$ 26,087	$ 23,385	$ 24,490	$ 28,256	$ 30,905	$ 25,633	$ 25,902	$ 22,533	$ 102,218	$ 104,973	$ 103,186
Heat transfer equipment [Member]
Segment Reporting Information [Line Items]
Net sales									37,086	43,764	27,927
Vacuum equipment [Member]
Segment Reporting Information [Line Items]
Net sales									27,236	22,891	43,635
All other [Member]
Segment Reporting Information [Line Items]
Net sales									$ 37,896	$ 38,318	$ 31,624