Leases - Maturities of Operating Lease Liabilities - ASC 842 (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Maturities of operating lease liabilities:
Remainder of 2019	$ 20,636
2020	25,099
2021	20,194
2022	15,763
2023	11,671
Thereafter	21,253
Total operating lease payments	114,616
Less: Imputed interest	8,958
Present value of lease liabilities	105,658
Maturities of finance lease liabilities
Remainder of 2019	15,199
2020	12,876
2021	10,119
2022	4,529
2023	3,062
2024 and thereafter	4,064
Total finance lease payments	49,849
Less: imputed interest	6,657
Present value of finance lease liabilities	$ 43,192