Fair Value of Financial Assets and Liabilities - Summary of Long-term Debt Carried at Amortized Cost on Condensed Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Book Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Current portion of long-term debt	$ 3,496	$ 1,019
Long-term debt, less current portion	10,771	13,079
Total	14,267	14,098
Approximate Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Current portion of long-term debt	3,496	1,019
Long-term debt, less current portion	10,500	13,035
Total	13,996	14,054
Level 2 \| Approximate Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Current portion of long-term debt	3,496	1,019
Long-term debt, less current portion	10,500	13,035
Total	$ 13,996	$ 14,054