Income Taxes - Reconciliation of Income Tax Expense at Statutory Federal Rate to Actual Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 29, 2019	Dec. 30, 2018
Income tax expense
Statutory (income) / expense	$ 50,618	$ 7,187	$ (2,790)
State income taxes, net of federal benefit	9,258	1,352	(376)
Nondeductible compensation	3,007	4,313	2,851
Noncontrolling interest – Piedmont	(2,447)	(1,826)	(1,238)
Valuation allowance change	(1,900)	1,290	1,566
Meals, entertainment and travel expense	1,476	2,440	2,734
Nondeductible fees and expenses	311	887	568
Adjustment for uncertain tax positions	114	(805)	694
Adjustment for federal tax legislation	0	0	(1,989)
Other, net	(1,494)	827	(151)
Income tax expense	$ 58,943	$ 15,665	$ 1,869
% pre-tax income (loss)
Statutory (income) / expense	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	3.80%	4.00%	2.80%
Nondeductible compensation	1.30%	12.60%	(21.50%)
Noncontrolling interest – Piedmont	(1.00%)	(5.30%)	9.30%
Valuation allowance change	(0.80%)	3.80%	(11.80%)
Meals, entertainment and travel expense	0.60%	7.10%	(20.60%)
Nondeductible fees and expenses	0.10%	2.60%	(4.30%)
Adjustment for uncertain tax positions	0.00%	(2.40%)	(5.20%)
Adjustment for federal tax legislation	0.00%	0.00%	15.00%
Other, net	(0.50%)	2.40%	1.20%
Income tax expense	24.50%	45.80%	(14.10%)