Leases - Net Lease Expense (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Net lease expense
Operating lease expense	$ 9,158
Short-term lease expense	487
Variable lease expense	2,152
Amortization of right-of-use assets	3
Interest on lease liabilities	2
Total finance lease expense	5
Less: Sublease income	(1,073)
Net lease expense	$ 10,729