Consecutive trading period.

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- Definition

Partnership unit exchange rate.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, Percentage of satisfied upon dividend-adjusted publicly traded shares.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ 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 210.5-02.29)
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

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- Definition

Number of shares for which recognition of cost was accelerated for award under share-based payment arrangement.

+ References

No definition available.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Equity-Based and Other Deferred Compensation - Additional Information (Details)		12 Months Ended
	Feb. 10, 2022 USD ($) shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 $ / shares shares	Dec. 31, 2020 $ / shares	Oct. 01, 2015 shares
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards \| $		$ 120,400,000
Weighted-average period for recognition of compensation expense related to unvested awards		1 year 3 months 18 days
Weighted-average grant date fair value \| $ / shares		$ 63.88	$ 73.45	$ 53.70
Granted		1,920,006
Shares outstanding		4,181,075	4,098,671
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		6.00%
RSU Awards Containing Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards \| $		$ 36,300,000
Weighted-average period for recognition of compensation expense related to unvested awards		2 years 3 months 18 days
Weighted-average grant date fair value \| $ / shares		$ 41.97		34.42
Awards with service condition requirement	5 years
Awards vesting percentage with service condition	20.00%
Weighted-average share price targets on consecutive trading period	20 days
Awards incremental cost \| $	$ 100
Awards with service and market condition vested	0
Granted		1,514,748	0
Shares outstanding		1,534,012	50,280
RSU Awards Containing Service and Market Conditions \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Assumed forfeiture rate		4.00%
Awards with service condition requirement		3 years
Awards incremental cost \| $	$ 100
RSU Awards Containing Service and Market Conditions \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Assumed forfeiture rate		6.00%
Awards with service condition requirement		5 years
Awards incremental cost \| $	$ 130
Partnership Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards \| $		$ 6,500,000
Assumed forfeiture rate		4.00%
Weighted-average period for recognition of compensation expense related to unvested awards		1 year
Weighted-average grant date fair value \| $ / shares		$ 62.05	$ 68.70	$ 49.92
Granted		77,588
Shares outstanding		178,067	248,595
Partnership Units \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		3 years
Partnership Units \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		5 years
Partnership Unit Awards Containing Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated unrecognized compensation expense related to unvested awards \| $		$ 25,500,000
Assumed forfeiture rate		4.00%
Weighted-average period for recognition of compensation expense related to unvested awards		2 years 4 months 24 days
Weighted-average grant date fair value \| $ / shares		$ 39.10
Awards with service condition requirement	5 years
Awards vesting percentage with service condition	20.00%
Weighted-average share price targets on consecutive trading period	20 days
Awards incremental cost \| $	$ 100
Awards with service and market condition vested	0
Granted		1,107,768
Shares outstanding		1,107,768
Partnership Unit Awards Containing Service and Market Conditions \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Awards incremental cost \| $	$ 100
Partnership Unit Awards Containing Service and Market Conditions \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Awards incremental cost \| $	$ 130
Class A Common Stock \| PJT Partners Holdings LP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exchange of Partnership unit to shares, number of shares per each unit		1
Class A Common Stock \| Restricted Share Awards \| CamberView
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
Granted		0	0
Shares outstanding		0
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					17,000,000
Shares available for issuance		2,400,000
Dividend Adjusted Publicly Traded Shares Of Class A Common Stock \| RSU Awards Containing Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, Percentage of satisfied upon dividend-adjusted publicly traded shares	50.00%	50.00%
Dividend Adjusted Publicly Traded Shares Of Class A Common Stock \| Partnership Unit Awards Containing Service and Market Conditions
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, Percentage of satisfied upon dividend-adjusted publicly traded shares	50.00%	50.00%