Employee Retirement and Profit Sharing Plans - Reconciliation of Projected Benefit Obligation and Fair Value of Plans Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Change in plan assets:
Fair value of plan assets at beginning of year	$ 344,760
Fair value of plan assets at end of year	299,208	$ 344,760
Pension Plan
Change in benefit obligation:
Benefit obligation at beginning of year	349,784	338,733
Service cost	2,928	3,007	$ 3,173
Interest cost	11,311	11,709
Plan amendments	0	1,233
Actuarial (gain) loss	(26,820)	19,921
Benefits paid	(23,105)	(24,819)
Benefit obligation at end of year	314,098	349,784	338,733
Change in plan assets:
Fair value of plan assets at beginning of year	344,760	282,183
Actual return (loss) on plan assets	(23,276)	48,038
Employer contributions	829	39,358
Benefits paid	(23,105)	(24,819)
Fair value of plan assets at end of year	299,208	344,760	$ 282,183
Funded status at end of year	$ (14,890)	$ (5,024)