Details of Certain Consolidated Balance Sheet Captions (Accounts Receivable, net) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Details of Certain Consolidated Balance Sheet Captions [Abstract]
Accounts receivable	$ 848,950	$ 843,935
Less: allowance for doubtful accounts	(53,412)	(51,501)
Accounts receivable, net	$ 795,538	$ 792,434

Details of Certain Consolidated Balance Sheet Captions [Abstract]

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

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