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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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

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- Details

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Accounts Receivable, net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unbilled revenues accrued		$ 21,000	$ 11,900
Past due receivables outstanding		$ 127,699	$ 107,628
Texas Customer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due receivables outstanding	$ 1,400
Texas Customer \| Litigation and Commercial Claims
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due receivables outstanding	1,400
Reserve for past due receivables	$ 1,400