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Borrowing Arrangements - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
	Sep. 25, 2015	Jan. 31, 2015	Dec. 25, 2015	Mar. 27, 2015	Feb. 05, 2015	Feb. 04, 2015	Feb. 02, 2015	Dec. 26, 2014
Debt Instrument [Line Items]
Unamortized debt issuance costs				$ 700,000
Amortization of debt discount			$ 600,000
Outstanding amounts			$ 76,100,000
Debt Instrument, covenant description			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.
Required cash balance			$ 35,000,000
Percentage of excess cash flow used for annual debt payment condition one			33.00%
New 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%
New term loan principal amount outstanding condition two			$ 10,000,000
Maximum [Member]
Debt Instrument [Line Items]
New term loan principal amount outstanding condition two			$ 20,000,000
Marchi Thermal Systems Inc [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing under credit facility					$ 29,700,000
First Quarter [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated leverage ratio for first quarter of next fiscal year			3.50%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing classified as long-term debt								$ 31,300,000
New Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Maturity date of debt			Feb. 02, 2019
Base rate interest			2.98%
Outstanding amount of borrowing under credit facility							$ 40,000,000
Outstanding amounts			$ 36,300,000
New Term Loan Credit Facility [Member] \| First Four Quarter [Member]
Debt Instrument [Line Items]
New term loan repaid			1,250,000
New Term Loan Credit Facility [Member] \| Remaining Twelve Quarter [Member]
Debt Instrument [Line Items]
New term loan repaid			$ 2,900,000
New Term Loan Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative instrument, notional amount	$ 20,000,000
New Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing under credit facility							$ 6,500,000
Credit agreement amendment date			Apr. 03, 2015
New line of credit facility maturity period			4 years
Outstanding amounts			$ 36,200,000
New Revolving Credit Facility [Member] \| Marchi Thermal Systems Inc [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing under credit facility					29,700,000
New Term Loan and New Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs			500,000
Outstanding amount of borrowing classified as long-term debt			$ 72,000,000
Loan and Security Agreement [Member] \| Revolving Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility						$ 40,000,000
Maturity date of debt			Jul. 03, 2016
Base rate interest		3.75%
Outstanding amount of borrowing under credit facility								31,300,000
Loan and Security Agreement [Member] \| Term Loan Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility						$ 40,000,000
Maturity date of debt			Jul. 03, 2016
Outstanding amount of borrowing under credit facility								$ 17,500,000
Base Rate Loans [Member]
Debt Instrument [Line Items]
Debt instrument interest rate			3.25%
Credit Agreement [Member] \| New Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility					40,000,000
Debt instrument interest rate			2.50%
Outstanding amounts			$ 36,300,000
Credit Agreement [Member] \| New Term Loan Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate	0.48%		0.48%
Credit Agreement [Member] \| New Term Loan Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Debt instrument interest rate			3.49%
Derivative instrument, notional amount			$ 19,300,000
Debt instrument LIBOR rate	0.99%
Credit Agreement [Member] \| New Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility					40,000,000
Debt instrument interest rate			3.50%
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
Bank Debt [Member] \| Credit Facility Czech Republic [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing classified as long-term debt			$ 3,600,000
Debt Interest rate, minimum			1.30%
Debt Interest rate, maximum			2.30%
Debt due date, start year			2015
Debt due date, end year			2020