Capital Lease - Future Minimum Capital Lease Payments (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 624
2020	624
2021	624
2022	624
2023	45
Total minimum lease payments	2,541
Less amount representing interest (1.53%)	(34)
Present value of net minimum payments	$ 2,507
Interest rate	1.53%
Accrued Liabilities
Lessee, Lease, Description [Line Items]
Present value of net minimum payments	$ 610
Other Noncurrent Liabilities
Lessee, Lease, Description [Line Items]
Present value of net minimum payments	$ 1,897