Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Number of defendants named in a legal action.

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Commitments and Contingencies - Narrative (Details)	3 Months Ended	12 Months Ended
Commitments and Contingencies - Narrative (Details)	Mar. 31, 2018 USD ($)	Oct. 31, 2016 defendant	Dec. 31, 2019 USD ($)
Other Commitments [Line Items]
Legal settlement	$ 5,500,000
Notes receivable, current			$ 800,000
Notes receivables, noncurrent			2,500,000
Receivable, unamortized discount			300,000
Houston Police Department, Environmental Enforcement \| Pending Litigation
Other Commitments [Line Items]
Number of defendants \| defendant		2
Estimate of possible loss			$ 250,000