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Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Deferred income tax assets: |  |
Net operating loss | $ 3,361 | $ 1,519
Research and development credits | 1,363 | 161
Stock compensation | 175 | 580
Deferred compensation | 705 | 389
Other | 398 | 160
Total deferred income tax assets | 6,002 | 2,809
Deferred income tax liabilities: |  |
Property and equipment | (47,626) | (33,761)
Goodwill and other intangible assets | (266) | (291)
Total deferred income tax liabilities | (47,892) | (34,052)
Net deferred income tax liabilities | $ (41,890) | $ (31,243)

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