Leases - Maturities of Lease Liabilities (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Operating Leases
2019 (excluding the three months ended March 31, 2019)	$ 12,210
2020	12,943
2021	9,775
2022	7,563
2023	6,254
After 2023	21,576
Total lease payments	70,321
Less imputed interest	(20,348)
Total	49,973
Finance Leases
2019 (excluding the three months ended March 31, 2019)	1,027
2020	631
2021	295
2022	117
2023	16
After 2023	2
Total lease payments	2,088
Less imputed interest	(89)
Total	$ 1,999