Line of Credit - Additional Information (Detail)	9 Months Ended
	Sep. 26, 2015 USD ($)
Line of Credit Facility [Line Items]
Available line of credit	$ 30,000,000
Line of credit, variable rate basis	LIBOR plus a fixed percentage between 1.50% and 2.00%
Minimum cash balance required to maintain under the credit agreement	$ 25,000,000
Line of credit, expiration date	Mar. 31, 2015
LIBOR | Minimum
Line of Credit Facility [Line Items]
Line of credit basis spread on variable rate	1.50%
LIBOR | Maximum
Line of Credit Facility [Line Items]
Line of credit basis spread on variable rate	2.00%