Leases - Operating and Finance Lease Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Feb. 01, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating
2019	$ 78,216
2020	91,707
2021	75,252
2022	63,681
2023	56,781
2024 and thereafter	164,320
Total lease payments	529,957
Less imputed interest	(100,117)
Total operating lease liabilities	429,840	$ 15,900	$ 433,400
Less current obligations	(87,669)			$ 0
Noncurrent operating lease liabilities	342,171			$ 0
Finance
2019	1,601
2020	1,649
2021	833
2022	566
2023	564
2024 and thereafter	2,756
Total lease payments	7,969
Less imputed interest	(1,683)
Finance Lease, Liability	6,286
Less current obligations	(1,641)
Long-term lease obligations	$ 4,645