Accounts Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Trade and other accounts receivable	$ 223,717	$ 211,244
Bank promissory notes	18,332	19,269
Allowance for doubtful accounts	(7,922)	(7,337)
Accounts receivable, net	234,127	223,176
Noncurrent receivables	$ 45,354	$ 45,061
Interest rate	2.00%

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Amount of allowance for credit loss on accounts receivable, classified as current.

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The weighted average interest rate charged on contract receivables maturing after one year.

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Amount, before allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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