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	Mar. 31, 2019	Dec. 31, 2018
Book Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Current portion of long-term debt	$ 2,056	$ 1,019
Long-term debt, less current portion	12,139	13,079
Total	14,195	14,098
Approximate Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Current portion of long-term debt	2,056	1,019
Long-term debt, less current portion	11,850	13,035
Total	13,906	14,054
Level 2 \| Approximate Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Current portion of long-term debt	2,056	1,019
Long-term debt, less current portion	11,850	13,035
Total	$ 13,906	$ 14,054