Leases Leases - Supplemental Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Leases [Abstract]
Operating Lease, Payments	$ 19,515
Finance Lease, Interest Expense	30
Finance Lease, Principal Payments	116	$ 0
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	11,546
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	$ 6,369
Operating Lease, Weighted Average Remaining Lease Term	4 years 7 months 6 days
Finance Lease, Weighted Average Remaining Lease Term	6 years 10 months 24 days
Operating Lease, Weighted Average Discount Rate, Percent	3.70%
Finance Lease, Weighted Average Discount Rate, Percent	2.90%