Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Future minimum lease payments [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 51,621
Lessee, Operating Lease, Liability, Payments, Due Year Two	45,992
Lessee, Operating Lease, Liability, Payments, Due Year Three	37,044
Lessee, Operating Lease, Liability, Payments, Due Year Four	24,711
Lessee, Operating Lease, Liability, Payments, Due Year Five	14,060
Lessee, Operating Lease, Liability, Payments, Due after Year Five	15,939
Lessee, Operating Lease, Liability, Payments, Due	189,367
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	11,032
Present Value of Lease Liability	$ 178,335
Operating Lease, Weighted Average Remaining Lease Term	4 years 6 months 25 days
Operating Lease, Weighted Average Discount Rate, Percent	3.41%
Operating Lease, Cost	$ 60,104	$ 57,235	$ 54,023
Variable Lease, Cost	13,778	$ 12,867	$ 12,138
Operating Lease, Payments	$ 56,617