Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 30, 2014
Loss Contingencies [Line Items]
Commitment for property and equipment purchases	$ 276,100
Loss contingency, damages awarded, value		$ 800
Insurance and claims	98,133	79,927	$ 83,866
Loss contingency, damages awarded, attorney fees and costs		$ 500
May 17, 2018 Verdict [Member]
Loss Contingencies [Line Items]
Loss contingency, damages awarded, value	92,000
Self insurance retained liability				$ 10,000
Insurance and claims	15,200
Loss contingency, receivable, noncurrent	79,200
Loss contingency, accrual, noncurrent	$ 79,200