Leases - Future Minimum Payments Due Under Non‐Cancelable Leases - ASC 840 (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Future minimum payments due under Operating Leases:
2019	$ 38,057
2020	29,346
2021	22,239
2022	16,782
2023	12,302
2024 and thereafter	18,874
Total lease payments	137,600
Future minimum payments due under Finance Leases
2019	20,080
2020	11,851
2021	9,018
2022	4,169
2023	2,244
2024 and thereafter	3,617
Total minimum lease payments	50,979
Less: imputed interest	(6,743)
Total net minimum lease payments	44,236
Less: Current portion of obligations under capital leases	(17,498)
Long-term portion of obligations under finance leases	$ 26,738