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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Borrowing Arrangements - Additional Information (Detail)	3 Months Ended	9 Months Ended
	Mar. 27, 2015 USD ($)	Sep. 23, 2016 USD ($)	Sep. 23, 2016 EUR (€)	Sep. 30, 2015 USD ($)	Jul. 31, 2015 EUR (€)	Feb. 05, 2015 USD ($)	Feb. 02, 2015 USD ($)
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 700,000	$ 400,000
Amortization of debt discount		$ 600,000
Required cash balance	$ 35,000,000
Debt Instrument, covenant description		The Credit Agreement requires the Company to maintain certain financial covenants including a consolidated fixed charge coverage ratio (as defined in the Credit Agreement) of at least 1.25 to 1.00 starting with the end of the first quarter of fiscal 2015 and a consolidated leverage ratio (as defined in the Credit Agreement) no greater than 3.50 to 1.00 starting with the end of the first quarter of fiscal 2015. The Credit Agreement also includes other customary affirmative and negative covenants. In December 2015, the Credit Agreement was amended to add a covenant requiring the Company to maintain a cash balance of $35.0 million at the end of each quarter. The Company was in compliance with all covenants for the quarter ended September 23, 2016.
Percentage of excess cash flow used for annual debt payment condition one		33.00%
Term loan principal amount outstanding condition one		$ 20,000,000
Percentage of excess cash flow used for annual debt payment condition two		25.00%
Minimum [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio for the next fiscal year	1.25%
Term loan principal amount outstanding condition two		$ 10,000,000
Maximum [Member]
Debt Instrument [Line Items]
Term loan principal amount outstanding condition two		$ 20,000,000
First Quarter [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated leverage ratio for first quarter of next fiscal year	3.50%
Marchi Thermal Systems Inc [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing under credit facility						$ 29,700,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit agreement amendment date		Apr. 03, 2015
Outstanding amount of borrowing under credit facility							$ 6,500,000
Line of credit facility maturity period		4 years
Outstanding amounts		$ 36,200,000
Revolving Credit Facility [Member] \| Marchi Thermal Systems Inc [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing under credit facility						$ 29,700,000
Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing under credit facility							40,000,000
Maturity date of debt		Feb. 02, 2019
Base rate interest		3.27%
Outstanding amounts		$ 29,200,000
Term Loan Credit Facility [Member] \| First Four Quarter [Member]
Debt Instrument [Line Items]
Term loan repaid		1,250,000
Term Loan Credit Facility [Member] \| Remaining Twelve Quarter [Member]
Debt Instrument [Line Items]
Term loan repaid		$ 2,900,000
Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility							40,000,000
Debt instrument interest rate		3.50%	3.50%
Credit Agreement [Member] \| Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility							40,000,000
Debt instrument variable interest rate		2.75%
Derivative instrument, notional amount				$ 20,000,000
Credit Agreement [Member] \| Term Loan Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		3.74%	3.74%
Derivative instrument, notional amount		$ 15,500,000
Debt instrument LIBOR rate				0.99%
Credit Agreement [Member] \| Term Loan Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate		0.52%
Credit Agreement [Member] \| Letter of Credit [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility							20,000,000
Credit Agreement [Member] \| Swing Line Sub-Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility							$ 5,000,000
Base Rate Loans [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		3.25%	3.25%
Bank Debt [Member]
Debt Instrument [Line Items]
Total debt balance		$ 69,200,000
Bank Debt [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Debt due date, start year		2016
Debt due date, end year		2020
Bank Debt [Member] \| Minimum [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate		1.30%
Bank Debt [Member] \| Maximum [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate		2.30%
Bank Debt [Member] \| Miconex [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Outstanding amounts		$ 4,200,000
Bank Debt [Member] \| Revolving Credit Facility [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Outstanding amounts		1,400,000	€ 1,200,000
Bank Debt [Member] \| Revolving Credit Facility [Member] \| U.S. [Member]
Debt Instrument [Line Items]
Outstanding amounts		3,800,000
Bank Debt [Member] \| Revolving Credit Facility [Member] \| Miconex [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Outstanding amounts		3,700,000	3,300,000
Bank Debt [Member] \| Revolving Credit Facility [Member] \| Miconex [Member] \| Maximum [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility \| €					€ 4,500,000
Bank Debt [Member] \| Term Loan Credit Facility [Member] \| Miconex [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility \| €					€ 800,000
Outstanding amounts		$ 500,000	€ 500,000