Commitments and Contingencies Schedule of Future Minimum Rental Payments (Details 1) $ in Thousands	Mar. 31, 2018 USD ($)
Operating leases
2018	$ 130,615
2019	112,001
2020	98,682
2021	93,167
Operating Leases, Future Minimum Payments, Due in Five Years	85,434
Thereafter	113,296
Total	633,195	[1]
Real Estate And Equipment [Member]
Operating leases
Total	550,574
Service, Support And Maintenance Agreements [Member]
Operating leases
Total	$ 82,621

[1] (1) Includes $550,574 in real estate and equipment leases and $82,621 in service and maintenance agreements.