Income Taxes - Reconciliation of Income Tax Expense at Statutory Federal Rate to Actual Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 01, 2017	Jan. 03, 2016	Dec. 28, 2014
Income Tax Disclosure [Abstract]
Statutory expense	$ 32,449	$ 34,692	$ 19,474
State income taxes, net of federal benefit	3,243	3,496	2,133
Noncontrolling interest – Piedmont	(2,406)	(2,261)	(1,835)
Adjustment for uncertain tax positions	(43)	51	30
Adjustment for state tax legislation	(625)	(1,145)
Valuation allowance change	(689)	(1,332)	1,203
Bargain purchase gain		(704)
Capital loss carryover			(854)
Manufacturing deduction benefit	(56)	(1,330)	(1,470)
Meals and entertainment	1,879	1,666	1,204
Other, net	2,297	945	(349)
Income tax expense	$ 36,049	$ 34,078	$ 19,536
Statutory expense	35.00%	35.00%	35.00%
State income taxes, net of federal benefit	3.50%	3.50%	3.80%
Noncontrolling interest – Piedmont	(2.60%)	(2.30%)	(3.30%)
Adjustment for uncertain tax positions		0.10%	0.10%
Adjustment for state tax legislation	(0.70%)	(1.20%)
Valuation allowance change	(0.70%)	(1.30%)	2.20%
Bargain purchase gain		(0.70%)
Capital loss carryover			(1.50%)
Manufacturing deduction benefit	(0.10%)	(1.30%)	(2.60%)
Meals and entertainment	2.00%	1.70%	2.20%
Other, net	2.50%	0.90%	(0.80%)
Income tax expense	38.90%	34.40%	35.10%