Reclassification Out of Accumulated Other Comprehensive Income to Statement of Operations (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 30, 2014		Mar. 31, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains	$ 176		$ 144
Prior service benefit	73	[1]	69	[1]
Total reclassifications	$ 249		$ 213

[1] The amortization of prior service benefit is included in the computation of net periodic pension cost and postretirement benefit; see Note N: "Retirement Plans."