Composition of Certain Financial Statement Captions (Receivables) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Items Included in Consolidated Statement of Financial Condition [Abstract]
Trade receivables	$ 77,063	$ 76,362
Fees earned, not billed	242,712	226,001
Other receivables	16,470	13,691
Receivables, Gross, Current	336,245	316,054
Less: Allowance for doubtful accounts	(1,101)	(718)
Receivables, net	$ 335,144	$ 315,336

Allowance for Doubtful Receivables

No definition available.

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- Definition

Receivables, Gross, Current

+ References

No definition available.

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- References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(c))
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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.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 310
-Section 45
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