Leases - Balance Sheet Classification of Lease Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Lease, Assets And Liabilities, Lessee [Abstract]
Operating lease assets	$ 23,333	$ 21,200	$ 0
Other current liabilities	5,485		0
Operating lease liabilities	19,192		$ 0
Present value of lease liabilities	24,677	$ 22,200
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Right-of-use assets	1,118
Accumulated depreciation	(250)
Right-of-use assets, net	868
Current liabilities	374
Non-current liabilities	465
Total finance lease liabilities	$ 839
Weighted Average Remaining Lease Term [Abstract]
Operating leases	4 years 8 months
Finance leases	3 years
Leases, Weighted Average Discount Rate [Abstract]
Operating leases	11.00%
Finance leases	7.20%
Before Adoption
Operating Lease, Assets And Liabilities, Lessee [Abstract]
Operating lease assets	$ 20,200
After Adoption
Operating Lease, Assets And Liabilities, Lessee [Abstract]
Operating lease assets	6,400
Finance Lease, Assets And Liabilities, Lessee [Abstract]
Accumulated depreciation	$ (3,300)