Selected Balance Sheet Information: Accounts Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Selected Balance Sheet Information [Abstract]
Accounts receivable, trade	$ 162,138	$ 144,747
Unbilled revenue	81,927	113,502
Less: Allowance for doubtful accounts	(5,162)	(2,444)
Accounts receivable, net	$ 238,903	$ 255,805

Selected Balance Sheet Information [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, 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 of allowance for credit loss on accounts receivable, classified as current.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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