Consecutive trading period.

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Partnership unit exchange rate.

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Percentage of equity awards in Former Parent that were converted into PJT equity awards.

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Share based compensation arrangement by share based payment award fair value assumptions expected forfeiture rate.

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Share based compensation arrangement by share based payment award spin off pro-ratably weighted average exercise price five.

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Share based compensation arrangement by share based payment award spin off pro-ratably weighted average exercise price four.

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Share based compensation arrangement by share based payment award spin off pro-ratably weighted average exercise price one.

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Share based compensation arrangement by share based payment award spin off pro-ratably weighted average exercise price three.

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Share based compensation arrangement by share based payment award spin off pro-ratably weighted average exercise price two.

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- Definition

Share based compensation arrangement by share based payment other than award vesting period.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Date the plan of reorganization is effective, in CCYY-MM-DD format.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Percentage of vesting of share-based compensation awards.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Equity-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Oct. 02, 2015 shares	Dec. 31, 2016 USD ($) $ / shares	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense in relation to classified awards		$ 89,010	$ 65,342	$ 90,396
Blackstone
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense in relation to classified awards			44,900
2015 Omnibus Incentive Plan \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized \| shares	12,200,000
PJT Partners Holdings LP \| Spinoff
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Internal reorganization effective date		Oct. 01, 2015
PJT Partners Holdings LP \| Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exchange of Partnership unit to shares, number of shares per each unit		1
PJT Equity Awards at Spin-off
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of equity awards in Former Parent that were converted into PJT equity awards	50.00%
Vesting period for other than awards	180 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of restricted stock units \| shares	963,517
Estimated unrecognized compensation expense related to unvested awards		$ 71,100
Weighted-average period for recognition of compensation expense related to unvested awards		1 year 3 months 18 days
Restricted Stock Units \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		3 years
Assumed forfeiture rate		1.00%
Restricted Stock Units \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		5 years
Assumed forfeiture rate		16.70%
Restricted Stock Units \| PJT Partners Holdings LP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Issuance of restricted stock units \| shares	554,850
Equity Classified Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense in relation to classified awards			$ 20,400
Partnership Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		5 years
Estimated unrecognized compensation expense related to unvested awards		$ 76,900
Assumed forfeiture rate		5.50%
Weighted-average period for recognition of compensation expense related to unvested awards		2 years 1 month 6 days
Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards		$ 22,700
Assumed forfeiture rate		5.50%
Weighted-average period for recognition of compensation expense related to unvested awards		2 years 4 months 24 days
Equity-based awards service condition requirement		5 years
Weighted-average share price targets on consecutive trading period		30 days
Consummation spin-off price one \| $ / shares		$ 48
Consummation spin-off price two \| $ / shares		55
Consummation spin-off price three \| $ / shares		63
Consummation spin-off price four \| $ / shares		71
Consummation spin-off price five \| $ / shares		$ 79
Service and Market Conditions \| Period Three
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based awards vesting percentage with service condition		20.00%
Service and Market Conditions \| Period Four
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based awards vesting percentage with service condition		30.00%
Service and Market Conditions \| Period Five
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based awards vesting percentage with service condition		50.00%