Employee Benefit Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 04, 2021	Mar. 29, 2020
Defined Benefit Plan Disclosure [Line Items]
Effect of settlement loss		$ 623
Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 961	1,082
Interest cost	10,107	12,681
Expected return on plan assets	(9,661)	(12,580)
Amortization of prior service cost	226	250
Amortization of net actuarial loss	6,871	6,876
Effect of settlement loss	0	623
Net periodic benefit cost (income)	8,504	8,932
Retiree Health and Life Insurance Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	94	83
Interest cost	50	84
Expected return on plan assets	(113)	(90)
Amortization of prior service cost	0	(68)
Amortization of net actuarial loss	(196)	(197)
Net periodic benefit cost (income)	$ (165)	$ (188)