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Borrowing Arrangements - Additional Information (Detail) - USD ($)	1 Months Ended	9 Months Ended
	Jan. 31, 2015	Sep. 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
Outstanding amount of borrowing classified as long-term debt		$ 76,900,000
Amortization of debt discount		$ 600,000
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		125.00%
New term loan principal amount outstanding condition two		$ 10,000,000
Maximum [Member]
Debt Instrument [Line Items]
Consolidated leverage ratio for first quarter of next fiscal year		350.00%
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
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing classified as long-term debt							$ 31,300,000
Revolving Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Maturity date of debt		Jul. 03, 2016
Base rate interest	3.75%
Term Loan Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Maturity date of debt		Jul. 03, 2016
New Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Maturity date of debt		Feb. 02, 2019
Base rate interest		2.70%
Outstanding amount of borrowing under credit facility						$ 40,000,000
Outstanding amounts		$ 37,500,000
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]
Credit agreement amendment date		Apr. 03, 2015
Outstanding amount of borrowing under credit facility						$ 6,500,000
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		$ 73,200,000
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
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
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		$ 37,500,000
Credit Agreement [Member] \| New Term Loan Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate		0.20%
Credit Agreement [Member] \| New Term Loan Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		3.49%
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		3.00%
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] \| New Term Loan and New Revolving Credit Facility [Member] \| Miconex [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing classified as long-term debt		$ 3,700,000
Debt Interest rate, minimum		1.30%
Debt Interest rate, maximum		10.50%
Debt due date, start year		2015
Debt due date, end year		2020