Leases - Supplemental cash flow and other information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Operating cash flows from operating leases	$ 9,834
Operating cash flows from finance leases	1,704
Financing cash flows from finance leases	$ 2,855	$ 7,626	$ 12,224