Composition of Certain Financial Statement Captions (Receivables) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Trade receivables	$ 99,106	$ 86,043
Fees earned, not billed	262,167	240,239
Other receivables	25,046	15,277
Gross receivables	386,319	341,559
Less: Allowance for doubtful accounts	(1,100)	(1,201)
Receivables, net	$ 385,219	$ 340,358

Receivables, Gross, Current

No definition available.

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- Definition

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.

+ References

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- Definition

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

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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- References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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