Leases - Leasing Activities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019 USD ($)
Leases [Abstract]
Operating Cash Flows for Finance Leases	$ 261
Operating Cash Flows for Operating Leases	62,541
Financing Cash Flows for Finance Leases	1,202
Total Cash Paid for Amounts Included in Measurement of Lease Liabilities	64,004
Right-of-Use Assets Obtained in Exchange for New Finance Lease Liabilities	0
Right-of-Use Assets Obtained in Exchange for New Operating Lease Liabilities, Net of Exercised Early Lease Termination Options	$ 14,891