Commitments and Contingencies - Narrative (Details) - Houston Police Department, Environmental Enforcement - Settled Litigation - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2020
Other Commitments [Line Items]
Legal settlement	$ 5.5
Notes receivable, current		$ 0.8
Notes receivables, noncurrent		2.3
Receivable, unamortized discount		$ 0.3

Amount, after allowance for credit loss, of financing receivable, classified as current. Includes, but is not limited to, notes and loan receivable.

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- Definition

Amount, after allowance for credit loss, of financing receivable, classified as noncurrent.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Cash received for the settlement of litigation during the current period.

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Disclosure of the unamortized amount of the discount on the note or receivable which is deducted from the face amount of the receivable or loan. The discount or premium is the difference between the present value and the face amount.

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