The value of compensation payable attributable to temporary equity.

No definition available.

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- Definition

The maximum period of time used to determine classification of temporary equity shares as compensation payable.

+ References

No definition available.

+ Details

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- Definition

The number of securities classified as temporary equity that have been purchased during the reporting period.

+ References

No definition available.

+ Details

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- Definition

The number of securities classified as temporary equity that have been sold (or granted) during the reporting period.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

+ 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(27)(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Share-Based Compensation Plans - Employee Shares (Details) - Tradeweb Markets LLC - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Predecessor
Activity of the Employee Shares
Employee Shares compensation payable			$ 0
Compensation expense relating to PRSUs, options and shares		$ 15,949,000	$ 26,100,000	$ 19,032,000
Predecessor \| Class C common stock
Activity of the Employee Shares
Outstanding, beginning of period	447	447	504	528
Purchased		0	5
Sold			(62)	(24)
Outstanding, end of period		447	447	504
Predecessor \| Class P(C) Shares
Activity of the Employee Shares
Outstanding, beginning of period	2	2	2	2
Purchased		0	0
Sold			0	0
Outstanding, end of period		2	2	2
Predecessor \| Class P-1(C) Shares
Activity of the Employee Shares
Outstanding, beginning of period	232	0	0	0
Purchased		232	0
Sold			0	0
Outstanding, end of period		232	0	0
Successor
Activity of the Employee Shares
Period of time to determine classification as compensation payable	6 months
Employee Shares compensation payable	$ 6,727,000
Compensation expense relating to PRSUs, options and shares	$ 9,413,000
Successor \| Class C common stock
Activity of the Employee Shares
Outstanding, beginning of period	447
Sold	0
Outstanding, end of period	447	447
Successor \| Class P(C) Shares
Activity of the Employee Shares
Outstanding, beginning of period	2
Sold	0
Outstanding, end of period	2	2
Successor \| Class P-1(C) Shares
Activity of the Employee Shares
Outstanding, beginning of period	232
Sold	0
Outstanding, end of period	232	232