Commitments and Contingencies - Receivables (Details)	12 Months Ended
Dec. 31, 2018
Minimum
Concentration of Credit Risk
Credit period for accounts receivable	30 days
Maximum
Concentration of Credit Risk
Credit period for accounts receivable	90 days

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.

No definition available.

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