Reconciliation of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016
Schedule of Unrecognized Tax Benefits [Line Items]
Balance at beginning of year	$ 589	$ 486
Increases related to current year tax positions	64	80
(Decreases) Increases related to prior year tax positions	(259)	76
Decreases related to settlements	(62)	(50)
Decreases related to lapse of statute of limitations	(40)	(3)
Balance at end of year	$ 292	$ 589