Receivables, Net - Summary of Receivables (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Management and advisory fees receivable	$ 3,869	$ 3,358
Unbilled receivables	3,540	3,036
Other receivables	2	2,249
Receivables	7,411	8,643
Allowance for doubtful receivables	(621)	(621)
Receivables, net	$ 6,790	$ 8,022

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

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For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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For an unclassified balance sheet, the amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms.

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For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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Amount due from parties in nontrade transactions, classified as other.

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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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