Summary of Significant Accounting Policies - Reclassifications (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2018
Summary of Significant Accounting Policies
Current portion of finance lease obligations	$ 615		$ 693
Long-term portion of finance lease obligations	2,715		$ 3,776
Deferred income taxes	$ 738	$ (2,400)

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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