The period over which has the option to purchase additional stock.

No definition available.

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- Definition

Amount of equity impact of cash distributions declared to unit-holder of limited liability company (LLC).

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Number of new stock issued during the period.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Subsequent Events (Details) - USD ($)					3 Months Ended
Subsequent Events (Details) - USD ($)	Nov. 06, 2019	Nov. 05, 2019	Oct. 22, 2019	Apr. 08, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019
Subsequent Event [Line Items]
Cash distribution payable					$ 100,000,000	$ 20,000,000	$ 59,350,000	$ 55,000,000	$ 25,000,000
Tradeweb Markets LLC
Subsequent Event [Line Items]
Share Price (per share)				$ 27.00
Number of LLC Interests held by Tradeweb Markets Inc				64.30%						64.30%
Number of LLC Interests held by non-controlling interest holders										35.70%
Over allotment
Subsequent Event [Line Items]
Shares issued				6,000,000
Class A common stock
Subsequent Event [Line Items]
Shares issued					46,000,000
Class A common stock \| Follow On Offering
Subsequent Event [Line Items]
Proceeds from offering, net of underwriting discounts and commissions			$ 704,300,000
Class A common stock \| Over allotment
Subsequent Event [Line Items]
Shares issued				6,000,000
Class B common stock
Subsequent Event [Line Items]
Shares issued				96,933,192	96,933,192
Subsequent Event
Subsequent Event [Line Items]
Cash distribution payable		$ 45,800,000
Subsequent Event \| Tradeweb Markets LLC
Subsequent Event [Line Items]
Number of LLC Interests held by Tradeweb Markets Inc			72.20%
Number of LLC Interests held by non-controlling interest holders			27.80%
Subsequent Event \| Class A common stock
Subsequent Event [Line Items]
Cash dividend declared	$ 0.08
Subsequent Event \| Class A common stock \| Follow On Offering
Subsequent Event [Line Items]
Shares issued			17,287,878
Share Price (per share)			$ 42.00
Subsequent Event \| Class A common stock \| Over allotment
Subsequent Event [Line Items]
Shares issued			2,593,181
Additional stock purchase period			30 days
Subsequent Event \| Class B common stock
Subsequent Event [Line Items]
Cash dividend declared	$ 0.08
Trade Web Markets LLC \| Subsequent Event
Subsequent Event [Line Items]
Shares repurchased			17,259,961
Trade Web Markets LLC \| Subsequent Event \| Class A common stock
Subsequent Event [Line Items]
Share Price (per share)			$ 42.00
Shares repurchased			27,917