Capital Transactions - Summary of the Awards Each Year (Detail) - Class B Common Stock [Member] - shares	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Schedule of Capitalization, Equity [Line Items]
Date of approval for award	Mar. 07, 2017	Mar. 08, 2016	Mar. 03, 2015
Fiscal year of service covered by award	2016	2015	2014
Shares settled in cash	18,980	19,080	19,080
Class B common stock shares issued	21,020	20,920	20,920
Total Class B Common Stock awarded	40,000	40,000	40,000