Tradeweb Markets (TW) 10-Q 29 Oct 21 2021 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2021	Oct. 20, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-38860
Entity Registrant Name	Tradeweb Markets Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	83-2456358
Entity Address, Address Line One	1177 Avenue of the Americas
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10036
City Area Code	646
Local Phone Number	430-6000
Title of 12(b) Security	Class A common stock, par value $0.00001
Trading Symbol	TW
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001758730
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Class A Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		105,129,747
Class B Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		96,933,192
Class C Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		1,654,825
Class D Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding (in shares)		28,877,108

Condensed Consolidated Statemen

Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 821,905	$ 791,280
Restricted cash	1,000	1,000
Receivable from brokers and dealers and clearing organizations	33,950	368
Deposits with clearing organizations	24,396	11,671
Accounts receivable, net of allowance for credit losses of $265 and $243 at September 30, 2021 and December 31, 2020, respectively	133,351	105,286
Furniture, equipment, purchased software and leasehold improvements, net of accumulated depreciation and amortization	28,079	33,814
Right-of-use assets	22,918	29,437
Software development costs, net of accumulated amortization	160,253	168,030
Goodwill	2,782,779	2,694,797
Intangible assets, net of accumulated amortization	1,204,806	1,182,034
Receivable from affiliates	2,806	111
Deferred tax asset	641,708	579,562
Other assets	78,549	82,460
Total assets	5,936,500	5,679,850
Liabilities
Payable to brokers and dealers and clearing organizations	33,828	252
Accrued compensation	113,038	129,288
Deferred revenue	29,780	23,193
Accounts payable, accrued expenses and other liabilities	38,649	42,692
Employee equity compensation payable	0	1,900
Lease liability	26,770	34,463
Payable to affiliates	3,390	5,142
Deferred tax liability	17,566	19,425
Tax receivable agreement liability	425,150	404,332
Total liabilities	688,171	660,687
Commitments and contingencies (Note 13)
Equity
Preferred stock, $0.00001 par value; 250,000,000 shares authorized; none issued or outstanding	0	0
Additional paid-in capital	4,366,044	4,143,094
Accumulated other comprehensive income (loss)	2,279	4,314
Retained earnings	221,947	156,041
Total stockholders' equity attributable to Tradeweb Markets Inc.	4,590,272	4,303,451
Non-controlling interests	658,057	715,712
Total equity	5,248,329	5,019,163
Total liabilities and equity	5,936,500	5,679,850
Class A Common Stock
Equity
Common stock	1	1
Class B Common Stock
Equity
Common stock	1	1
Class C Common Stock
Equity
Common stock	0	0
Class D Common Stock
Equity
Common stock	$ 0	$ 0

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Financial Condition (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts receivable, allowance for credit losses	$ 265	$ 243
Preferred stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Preferred stock, shares authorized (in shares)	250,000,000	250,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	105,261,065	98,075,465
Common stock, shares outstanding (in shares)	105,261,065	98,075,465
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, shares authorized (in shares)	450,000,000	450,000,000
Common stock, shares issued (in shares)	96,933,192	96,933,192
Common stock, shares outstanding (in shares)	96,933,192	96,933,192
Class C Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, shares authorized (in shares)	350,000,000	350,000,000
Common stock, shares issued (in shares)	1,654,825	3,139,821
Common stock, shares outstanding (in shares)	1,654,825	3,139,821
Class D Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common Stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	28,877,108	30,871,381
Common stock, shares outstanding (in shares)	28,877,108	30,871,381

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues
Total revenue	$ 265,325	$ 212,870	$ 799,564	$ 659,583
Expenses
Employee compensation and benefits	98,036	83,967	300,107	263,353
Depreciation and amortization	44,823	38,857	127,656	113,952
Technology and communications	14,747	12,037	42,248	34,397
General and administrative	9,561	8,657	21,809	24,520
Professional fees	8,897	7,388	28,993	20,908
Occupancy	3,733	3,443	11,104	10,678
Total expenses	179,797	154,349	531,917	467,808
Operating income	85,528	58,521	267,647	191,775
Net interest income (expense)	(361)	(349)	(1,179)	64
Income before taxes	85,167	58,172	266,468	191,839
Provision for income taxes	(19,862)	(11,124)	(53,365)	(39,898)
Net income	65,305	47,048	213,103	151,941
Less: Net income attributable to non-controlling interests	10,542	10,236	35,165	40,705
Net income attributable to Tradeweb Markets Inc.	$ 54,763	$ 36,812	$ 177,938	$ 111,236
Earnings Per Share [Abstract]
Basic (in dollars per share)	$ 0.27	$ 0.20	$ 0.89	$ 0.63
Diluted (in dollars per share)	$ 0.26	$ 0.19	$ 0.86	$ 0.60
Weighted average shares outstanding
Basic (in shares)	202,238,122	187,774,170	201,029,196	177,257,994
Diluted (in shares)	208,197,439	194,955,695	206,908,330	185,026,108
Transaction fees and commissions
Revenues
Total revenue	$ 206,316	$ 160,175	$ 629,513	$ 503,753
Subscription fees
Revenues
Total revenue	41,390	36,217	117,141	105,706
Refinitiv market data fees
Revenues
Total revenue	15,002	14,273	45,045	43,466
Other
Revenues
Total revenue	$ 2,617	$ 2,205	$ 7,865	$ 6,658

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 65,305	$ 47,048	$ 213,103	$ 151,941
Foreign currency translation adjustments, with no tax benefit for each of the three and nine months ended September 30, 2021 and 2020	(2,802)	3,381	(2,442)	(1,739)
Other comprehensive income (loss), net of tax	(2,802)	3,381	(2,442)	(1,739)
Comprehensive income	62,503	50,429	210,661	150,202
Less: Net income attributable to non-controlling interests	10,542	10,236	35,165	40,705
Less: Foreign currency translation adjustments attributable to non-controlling interests	(367)	588	(321)	(715)
Comprehensive income attributable to Tradeweb Markets Inc.	52,328	39,605	175,817	110,212
Comprehensive income - Tradeweb Markets Inc.
Net income attributable to Tradeweb Markets Inc.	54,763	36,812	177,938	111,236
Foreign currency translation adjustments attributable to Tradeweb Markets Inc.	(2,435)	2,793	(2,121)	(1,024)
Comprehensive income - Non-controlling interests
Comprehensive income attributable to non-controlling interests	$ 10,175	$ 10,824	$ 34,844	$ 39,990

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustment, tax benefit	$ 0	$ 0	$ 0	$ 0

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Equity Incentive Plan	Equity-settled PRSUs	RSUs	Common StockClass A Common Stock	Common StockClass B Common Stock	Common StockClass C Common Stock	Common StockClass D Common Stock	Additional Paid-In Capital	Additional Paid-In CapitalEquity Incentive Plan	Additional Paid-In CapitalEquity-settled PRSUs	Additional Paid-In CapitalRSUs	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Non- Controlling Interests
Beginning balance ( in shares) at Dec. 31, 2019					66,408,328	96,933,192	8,328,983	50,853,172
Beginning balance at Dec. 31, 2019	$ 4,592,745				$ 1	$ 1	$ 0	$ 1	$ 3,329,386				$ 1,366	$ 47,833	$ 1,214,157
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations (in shares)					1,920,941		(939,000)	(981,941)
Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations	(336)							$ (1)	(335)
Tax receivable agreement liability and deferred taxes arising from LLC Interest ownership exchanges	32,736								32,736
Issuance of common stock from equity incentive plans (in shares)					2,341,171
Issuance of common stock from equity incentive plans	35,422								35,422
Adjustments to non-controlling interests	0								45,436				7		(45,443)
Dividends	(13,400)													(13,400)
Stock-based compensation expense			$ 5,407	$ 315							$ 5,407	$ 315
Stock-based compensation expense under the Option Plan	2,249								2,249
Payroll taxes paid for stock-based compensation exercises	(23,991)								(23,991)
Net income	62,485													43,928	18,557
Foreign currency translation adjustments	(4,784)												(3,552)		(1,232)
Ending balance (in shares) at Mar. 31, 2020					70,670,440	96,933,192	7,389,983	49,871,231
Ending balance at Mar. 31, 2020	4,688,848				$ 1	$ 1	$ 0	$ 0	3,426,625				(2,179)	78,361	1,186,039
Beginning balance ( in shares) at Dec. 31, 2019					66,408,328	96,933,192	8,328,983	50,853,172
Beginning balance at Dec. 31, 2019	4,592,745				$ 1	$ 1	$ 0	$ 1	3,329,386				1,366	47,833	1,214,157
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Payroll taxes paid for stock-based compensation exercises	(71,800)
Net income	151,941
Foreign currency translation adjustments	(1,739)
Ending balance (in shares) at Sep. 30, 2020					90,985,582	96,933,192	5,109,991	34,403,255
Ending balance at Sep. 30, 2020	4,879,219				$ 1	$ 1	$ 0	$ 0	3,940,592				100	116,161	822,364
Beginning balance ( in shares) at Mar. 31, 2020					70,670,440	96,933,192	7,389,983	49,871,231
Beginning balance at Mar. 31, 2020	4,688,848				$ 1	$ 1	$ 0	$ 0	3,426,625				(2,179)	78,361	1,186,039
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations (in shares)					17,747,968		(2,279,992)	(15,467,976)
Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations	(1,406)								(1,406)
Tax receivable agreement liability and deferred taxes arising from LLC Interest ownership exchanges	127,846								127,846
Issuance of common stock from equity incentive plans (in shares)					2,223,700
Issuance of common stock from equity incentive plans	27,197								27,197
Adjustments to non-controlling interests	0								379,623				(249)		(379,374)
Distributions to non-controlling interests	(3,605)														(3,605)
Dividends	(14,483)													(14,483)
Stock-based compensation expense			7,392	1,675							7,392	1,675
Stock-based compensation expense under the Option Plan	1,279								1,279
Payroll taxes paid for stock-based compensation exercises	(47,672)								(47,672)
Net income	42,408													30,496	11,912
Foreign currency translation adjustments	(336)												(265)		(71)
Ending balance (in shares) at Jun. 30, 2020					90,642,108	96,933,192	5,109,991	34,403,255
Ending balance at Jun. 30, 2020	4,829,143				$ 1	$ 1	$ 0	$ 0	3,922,559				(2,693)	94,374	814,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations	(766)								(766)
Issuance of common stock from equity incentive plans (in shares)					343,474
Issuance of common stock from equity incentive plans	10,700								10,700
Adjustments to non-controlling interests	0								(1,478)						1,478
Distributions to non-controlling interests	(4,839)														(4,839)
Dividends	(15,025)													(15,025)
Stock-based compensation expense			6,778	1,684							6,778	1,684
Stock-based compensation expense under the Option Plan	1,295								1,295
Payroll taxes paid for stock-based compensation exercises	(180)								(180)
Net income	47,048													36,812	10,236
Foreign currency translation adjustments	3,381												2,793		588
Ending balance (in shares) at Sep. 30, 2020					90,985,582	96,933,192	5,109,991	34,403,255
Ending balance at Sep. 30, 2020	4,879,219				$ 1	$ 1	$ 0	$ 0	3,940,592				100	116,161	822,364
Beginning balance ( in shares) at Dec. 31, 2020					98,075,465	96,933,192	3,139,821	30,871,381
Beginning balance at Dec. 31, 2020	5,019,163				$ 1	$ 1	$ 0	$ 0	4,143,094				4,314	156,041	715,712
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Activities related to the follow-on offering and other exchanges of LLC Interests, net of offering costs and cancellations (in shares)					3,479,269		(1,484,996)	(1,994,273)
Tax receivable agreement liability and deferred taxes arising from LLC Interest ownership exchanges	65,177								65,177
Issuance of common stock from equity incentive plans (in shares)					3,088,545
Issuance of common stock from equity incentive plans	46,397								46,397
Deferred taxes arising from issuance of common stock from equity incentive plans		$ 6,417								$ 6,417
Adjustments to non-controlling interests	0								80,665				85		(80,750)
Distributions to non-controlling interests	(2,504)														(2,504)
Dividends	(16,030)													(16,030)
Stock-based compensation expense			5,997	2,523							5,997	2,523
Stock-based compensation expense under the Option Plan	2,240								2,240
Payroll taxes paid for stock-based compensation exercises	(45,464)								(45,464)
Net income	81,565													67,859	13,706
Foreign currency translation adjustments	(343)												(297)		(46)
Ending balance (in shares) at Mar. 31, 2021					104,643,279	96,933,192	1,654,825	28,877,108
Ending balance at Mar. 31, 2021	5,165,138				$ 1	$ 1	$ 0	$ 0	4,307,046				4,102	207,870	646,118
Beginning balance ( in shares) at Dec. 31, 2020					98,075,465	96,933,192	3,139,821	30,871,381
Beginning balance at Dec. 31, 2020	5,019,163				$ 1	$ 1	$ 0	$ 0	4,143,094				4,314	156,041	715,712
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Payroll taxes paid for stock-based compensation exercises	(56,600)
Net income	213,103
Foreign currency translation adjustments	(2,442)
Ending balance (in shares) at Sep. 30, 2021					105,261,065	96,933,192	1,654,825	28,877,108
Ending balance at Sep. 30, 2021	5,248,329				$ 1	$ 1	$ 0	$ 0	4,366,044				2,279	221,947	658,057
Beginning balance ( in shares) at Mar. 31, 2021					104,643,279	96,933,192	1,654,825	28,877,108
Beginning balance at Mar. 31, 2021	5,165,138				$ 1	$ 1	$ 0	$ 0	4,307,046				4,102	207,870	646,118
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from equity incentive plans (in shares)					1,127,573
Issuance of common stock from equity incentive plans	21,139								21,139
Deferred taxes arising from issuance of common stock from equity incentive plans		23,281								23,281
Adjustments to non-controlling interests	0								4,797				1		(4,798)
Distributions to non-controlling interests	(1,969)														(1,969)
Dividends	(16,142)												0	(16,142)
Share repurchases pursuant to the share repurchase program (in shares)					(617,644)
Share repurchases pursuant to the Share Repurchase Program	(51,676)													(51,676)
Deferred taxes arising from share repurchases	(12,816)								(12,816)
Stock-based compensation expense			7,826	3,815							7,826	3,815
Stock-based compensation expense under the Option Plan	766								766
Payroll taxes paid for stock-based compensation exercises	(7,970)								(7,970)
Net income	66,233													55,316	10,917
Foreign currency translation adjustments	703												611		92
Ending balance (in shares) at Jun. 30, 2021					105,153,208	96,933,192	1,654,825	28,877,108
Ending balance at Jun. 30, 2021	5,198,328				$ 1	$ 1	$ 0	$ 0	4,347,884				4,714	195,368	650,360
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from equity incentive plans (in shares)					248,026
Issuance of common stock from equity incentive plans	4,441								4,441
Deferred taxes arising from issuance of common stock from equity incentive plans		$ 1,481								$ 1,481
Adjustments to non-controlling interests	0								(16)						16
Distributions to non-controlling interests	(2,494)														(2,494)
Dividends	(16,184)													(16,184)
Share repurchases pursuant to the share repurchase program (in shares)					(140,169)
Share repurchases pursuant to the Share Repurchase Program	(12,000)													(12,000)
Stock-based compensation expense			$ 8,220	$ 4,401							$ 8,220	$ 4,401
Stock-based compensation expense under the Option Plan	1,155								1,155
Payroll taxes paid for stock-based compensation exercises	(3,139)								(3,139)
Net income	65,305													54,763	10,542
Foreign currency translation adjustments	(2,802)												(2,435)		(367)
Other - See Note 10	1,617								1,617
Ending balance (in shares) at Sep. 30, 2021					105,261,065	96,933,192	1,654,825	28,877,108
Ending balance at Sep. 30, 2021	$ 5,248,329				$ 1	$ 1	$ 0	$ 0	$ 4,366,044				$ 2,279	$ 221,947	$ 658,057

Condensed Consolidated Statem_7

Condensed Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Limited Liability Company (LLC) Members' Equity [Abstract]
Dividends (in dollars per share)	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08

Condensed Consolidated Statem_8

Condensed Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Net income	$ 213,103,000	$ 151,941,000
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	127,656,000	113,952,000
Stock-based compensation expense	36,943,000	28,074,000
Deferred taxes	47,080,000	34,735,000
(Increase) decrease in operating assets:
Receivable from/payable to brokers and dealers and clearing organizations, net	(7,000)	(356,000)
Deposits with clearing organizations	5,413,000	(477,000)
Accounts receivable	(25,837,000)	(5,957,000)
Receivable from/payable to affiliates, net	(5,335,000)	6,026,000
Other assets	4,754,000	(17,462,000)
Increase (decrease) in operating liabilities:
Accrued compensation	(17,366,000)	(17,312,000)
Deferred revenue	5,996,000	5,868,000
Accounts payable, accrued expenses and other liabilities	(4,130,000)	4,022,000
Employee equity compensation payable	(1,900,000)	478,000
Net cash provided by operating activities	386,370,000	303,532,000
Cash flows from investing activities
Cash paid for acquisitions, net of cash acquired	(208,857,000)	0
Purchases of furniture, equipment, software and leasehold improvements	(9,714,000)	(6,484,000)
Capitalized software development costs	(25,813,000)	(22,864,000)
Net cash used in investing activities	(244,384,000)	(29,348,000)
Cash flows from financing activities
Share repurchases pursuant to the Share Repurchase Program	(63,676,000)	0
Proceeds from stock-based compensation exercises	71,977,000	69,534,000
Proceeds from issuance of Class A common stock in follow-on offering, net of underwriting discounts	0	626,267,000
Purchase of LLC Interests	0	(626,267,000)
Offering costs from issuance of Class A common stock in follow-on offering	0	(2,403,000)
Dividends	(48,356,000)	(42,908,000)
Distributions to non-controlling interests	(6,967,000)	(8,443,000)
Payroll taxes paid for stock-based compensation	(56,573,000)	(71,843,000)
Payments on tax receivable agreement liability	(6,849,000)	0
Net cash used in financing activities	(110,444,000)	(56,063,000)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(917,000)	(1,480,000)
Net increase (decrease) in cash, cash equivalents and restricted cash	30,625,000	216,641,000
Cash, cash equivalents and restricted cash
Beginning of period	792,280,000	461,711,000
End of period	822,905,000	678,352,000
Supplemental disclosure of cash flow information
Income taxes paid, net of (refunds)	1,104,000	17,034,000
Non-cash financing activities - Items arising from LLC Interest ownership changes
Other - See Note 10	1,617,000	0
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Cash and cash equivalents	821,905,000
Restricted cash	1,000,000
Cash, cash equivalents and restricted cash shown in the statement of cash flows	822,905,000	678,352,000
Adjusted For Refinitiv Transaction
Non-cash financing activities - Items arising from LLC Interest ownership changes
Establishment of liabilities under tax receivable agreement	27,666,000	132,136,000
Deferred tax asset	$ 111,206,000	$ 296,504,000

Organization

Organization	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Tradeweb Markets Inc. (the “Corporation”) was incorporated as a Delaware corporation on November 7, 2018 to carry on the business of Tradeweb Markets LLC (“TWM LLC”) following the completion of a series of reorganization transactions on April 4, 2019 (the “Reorganization Transactions”), in connection with Tradeweb Markets Inc.'s initial public offering (the “IPO”), which closed on April 8, 2019. Following the Reorganization Transactions, Refinitiv Holdings Limited ( unless otherwise stated or the context otherwise requires, together with all of its subsidiaries, “Refinitiv”) owned an indirect majority ownership interest in the Company (as defined below). On January 29, 2021, London Stock Exchange Group plc (“LSEG”) completed its acquisition of Refinitiv from a consortium, including certain investment funds affiliated with The Blackstone Group Inc. (f/k/a The Blackstone Group L.P.) (“Blackstone”) as well as Thomson Reuters Corporation (“TR”), in an all share transaction (the “LSEG Transaction”). In connection with the LSEG Transaction, the Corporation became a consolidating subsidiary of LSEG. Prior to the LSEG Transaction, the Corporation was a consolidating subsidiary of BCP York Holdings, (“BCP”), a company owned by certain investment funds affiliated with Blackstone, through BCP’s previous majority ownership interest in Refinitiv. The Corporation is a holding company whose principal asset is LLC Interests (as defined below) of TWM LLC. As the sole manager of TWM LLC, the Corporation operates and controls all of the business and affairs of TWM LLC and, through TWM LLC and its subsidiaries, conducts the Corporation’s business. As a result of this control, and because the Corporation has a substantial financial interest in TWM LLC, the Corporation consolidates the financial results of TWM LLC and reports a non-controlling interest in the Corporation’s condensed consolidated financial statements. As of September 30, 2021, Tradeweb Markets Inc. owns 86.9% of TWM LLC and the non-controlling interest holders own the remaining 13.1% of TWM LLC. As of December 31, 2020, Tradeweb Markets Inc. owned 85.1% of TWM LLC and the non-controlling interest holders owned the remaining 14.9% of TWM LLC. Unless the context otherwise requires, references to the “Company” refer to Tradeweb Markets Inc. and its consolidated subsidiaries, including TWM LLC, following the completion of the Reorganization Transactions, and TWM LLC and its consolidated subsidiaries prior to the completion of the Reorganization Transactions. The Company is a leader in building and operating electronic marketplaces for a global network of clients across the institutional, wholesale and retail client sectors. The Company’s principal subsidiaries include: • Tradeweb LLC (“TWL”), a registered broker-dealer under the Securities Exchange Act of 1934, a member of the Financial Industry Regulatory Authority (“FINRA”), a registered independent introducing broker with the Commodities Future Trading Commission (“CFTC”) and a member of the National Futures Association (“NFA”). • Dealerweb Inc. (“DW”) (formerly known as Hilliard Farber & Co., Inc.), a registered broker-dealer under the Securities Exchange Act of 1934 and a member of FINRA. DW is also registered as an introducing broker with the CFTC and NFA. • Tradeweb Direct LLC (“TWD”) (formerly known as BondDesk Trading LLC), a registered broker-dealer under the Securities Exchange Act of 1934 and a member of FINRA. • Execution Access, LLC, (“EA”), acquired in June 2021, a registered broker-dealer under the Securities Exchange Act of 1934 and a member of FINRA. • Tradeweb Europe Limited (“TEL”), a Multilateral Trading Facility regulated by the Financial Conduct Authority (the “FCA”) in the UK, which maintains branches in Asia which are regulated by certain Asian securities regulators. • TW SEF LLC (“TW SEF”), a Swap Execution Facility (“SEF”) regulated by the CFTC. • DW SEF LLC (“DW SEF”), a SEF regulated by the CFTC. • Tradeweb Japan K.K. (“TWJ”), a security house regulated by the Japanese Financial Services Agency (“JFSA”) and the Japan Securities Dealers Association (“JSDA”). • Tradeweb EU B.V. (“TWEU”), a Trading Venue and Approved Publication Arrangement regulated by the Netherlands Authority for the Financial Markets (“AFM”). • Tradeweb Execution Services Limited (“TESL”), a Banks, Building Societies and Investment Firm (“BIPRU Firm”) regulated by the FCA in the UK. On February 2, 2021, the Company announced that it entered into a definitive agreement to acquire Nasdaq’s U.S. fixed income electronic trading platform. The acquired Nasdaq platform (formerly known as eSpeed) is a fully executable central order limit book (CLOB) for electronic trading in on-the-run (OTR) U.S. government bonds. The $190.0 million, all-cash transactio n closed on June 25, 2021 (the “NFI Acquisition”) . See Note 4 – Acquisitions for additional details on this acquisition. A majority interest of Refinitiv (formerly the Thomson Reuters Financial & Risk Business) was acquired by BCP on October 1, 2018 (the “Refinitiv Transaction”) from TR. The Refinitiv Transaction resulted in a new basis of accounting for certain of the Company's assets and liabilities beginning on October 1, 2018. See Note 2 – Significant Accounting Policies for a description of pushdown accounting applied as a result of the Refinitiv Transaction. In connection with the Reorganization Transactions, TWM LLC’s limited liability company agreement (the “TWM LLC Agreement”) was amended and restated to, among other things, (i) provide for a new single class of common membership interests in TWM LLC (the “LLC Interests”), (ii) exchange all of the then existing membership interests in TWM LLC for LLC Interests and (iii) appoint the Corporation as the sole manager of TWM LLC. As used herein, references to “Continuing LLC Owners” refer collectively to (i) those “ Original LLC Owners ” , incl uding an indirect subsidiary of Refinitiv, certain investment and commercial banks (collectively, the “Bank Stockholders”) and members of management, that contin ued to own LLC Interests after the completion of the IPO and Reorganization Transactions, that received shares of Class C common stock, par value $0.00001 per share, of the Corporation (the “Class C common stock”), shares of Class D common stock, par value $0.00001 per share, of the Corporation (the “Class D common stock”) or a combination of both, as the case may be, in connection with the completion of the Reorganization Transactions, and that may redeem or exchange their LLC Interests for shares of Class A common stock, par value $0.00001 per share, of the Corporation (the “Class A common stock”) or Class B common stock, par value $0.00001 per share, of the Corporation (the “Class B common stock”) and (ii) solely with respect to the Tax Receivable Agreement (as defined in Note 7 – Tax Receivable Agreement), also includes those Original LLC Owners, including certain Bank Stockholders, that disposed of all of their LLC Interests for cash in connection with the IPO. As of September 30, 2021: • The public investors collectively owned 105,261,065 shares of Class A common stock, representing 7.7% of the combined voting power of Tradeweb Markets Inc.’s issued and outstanding common stock and indirectly, through Tradeweb Markets Inc., owned 45.2% of the economic interest in TWM LLC; • Refinitiv collectively owned 96,933,192 shares of Class B common stock and 22,988,329 shares of Class D common stock, representing 87.9% of the combined voting power of Tradeweb Markets Inc.’s issued and outstanding common stock and directly and indirectly, through Tradeweb Markets Inc., owned 51.5% of the economic interest in TWM LLC; and • The Bank Stockholders that continue to own LLC Interests collectively owned 1,654,825 shares of Class C common stock and 5,767,435 shares of Class D common stock, representing 4.3% of the combined voting power of Tradeweb Markets Inc.’s issued and outstanding common stock and directly own 3.2% of the economic interest in TWM LL C. As of September 30, 2021, only Barclays Capital Inc. and Credit Suisse Securities (USA) LLC remained as Bank Stockholders. • Other stockholders that continue to own LLC Interests also collectively owned 121,344 shares of Class D common stock, representing less than 0.1% of the combined voting power of Tradeweb Markets Inc.’s issued and outstanding common stock and directly own less than 0.1% of the economic interest in TWM LLC.

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies The following is a summary of significant accounting policies: Basis of Presentation The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. As discussed in Note 1 – Organization, as a result of the Reorganization Transactions, Tradeweb Markets Inc. consolidates TWM LLC and its subsidiaries and TWM LLC is considered to be the predecessor to Tradeweb Markets Inc. for financial reporting purposes. Tradeweb Markets Inc. had no business transactions or activities and no substantial assets or liabilities prior to the Reorganization Transactions. The condensed consolidated financial statements represent the financial condition and results of operations of the Company and report a non-controlling interest related to the LLC Interests held by the Continuing LLC Owners. These condensed consolidated financial statements are unaudited and should be read in conjunction with the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. The consolidated financial information as of December 31, 2020 has been derived from audited financial statements not included herein. These unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) with respect to interim financial reporting and Form 10-Q. In accordance with such rules and regulations, certain disclosures that are normally included in annual financial statements have been omitted. These unaudited condensed consolidated financial statements reflect all normal and recurring adjustments that are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates and the difference may be material to the condensed consolidated financial statements. Reclassifications Certain reclassifications have been made to prior periods' financial information to conform to the current year presentation. This primarily includes an aggregation of transaction fees and commissions into a single revenue category titled “transaction fees and commissions” for all periods presented in condensed consolidated income statements. These reclassifications had no impact on total consolidated revenue or consolidated net income. Business Combinations Business combinations are accounted for under the purchase method of accounting pursuant to Accounting Standards Codification (“ASC”) 805, Business Combinations (“ASC 805”) . The total cost of an acquisition is allocated to the underlying net assets based on their respective estimated fair values. The excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. The fair value of assets acquired and liabilities assumed is determined based on assumptions that reasonable market participants would use in the principal (or most advantageous) market for the asset or liability. Determining the fair value of certain assets acquired and liabilities assumed is judgmental in nature and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash flows, discount rates, growth rates, customer attrition rates and asset lives. Pushdown Accounting In connection with the Refinitiv Transaction, a majority interest of Refinitiv (formerly the Thomson Reuters Financial & Risk Business) was acquired by BCP on October 1, 2018 from TR. The Refinitiv Transaction was accounted for by Refinitiv in accordance with the acquisition method of accounting pursuant to ASC 805 , and pushdown accounting was applied to Refinitiv to record the fair value of the assets and liabilities of Refinitiv as of October 1, 2018, the date of the Refinitiv Transaction. The Company, as a consolidating subsidiary of Refinitiv, also accounted for the Refinitiv Transaction using pushdown accounting which resulted in a new fair value basis of accounting for certain of the Company’s assets and liabilities beginning on October 1, 2018. Under the pushdown accounting applied, the excess of the fair value of the Company above the fair value accounting basis of the net assets and liabilities of the Company as of October 1, 2018 was recorded as goodwill. The fair value of assets acquired and liabilities assumed was determined based on assumptions that reasonable market participants would use in the principal (or most advantageous) market for the asset or liability. The adjusted valuations primarily affected the values of the Company’s long-lived and indefinite-lived intangible assets, including software development costs. Cash and Cash Equivalents Cash and cash equivalents consists of cash and highly liquid investments (such as short-term money market instruments) with original maturities at the time of purchase of three months or less. Allowance for Credit Losses The Company continually monitors collections and payments from its clients and maintains an allowance for credit losses. The allowance for credit losses is based on an estimate of the amount of potential credit losses in existing accounts receivable, as determined from a review of aging schedules, past due balances, historical collection experience and other specific account data. Careful analysis of the financial condition of our counterparties is also performed. Once determined uncollectible, aged balances are written off as credit loss expense, which is included in general and administrative expenses on the condensed consolidated statements of income. See Note 12 – Credit Risk for additional information. Receivable from and Payable to Brokers and Dealers and Clearing Organizations Receivable from and payable to brokers and dealers and clearing organizations consists of proceeds from transactions executed on the Company’s wholesale platform which failed to settle due to the inability of a transaction party to deliver or receive the transacted security. These securities transactions are generally collateralized by those securities. Until the failed transaction settles, a receivable from (and a matching payable to) brokers and dealers and clearing organizations is recognized for the proceeds from the unsettled transaction. Deposits with Clearing Organizations Deposits with clearing organizations are comprised of cash deposits. Furniture, Equipment, Purchased Software and Leasehold Improvements Furniture, equipment, purchased software and leasehold improvements are carried at cost less accumulated depreciation. Depreciation for furniture, equipment and purchased software is computed on a straight-line basis over the estimated useful lives of the related assets, ranging from three Furniture, equipment, purchased software and leasehold improvements are tested for impairment whenever events or changes in circumstances suggest that an asset’s carrying value may not be fully recoverable in accordance with ASC 360, Property, Plant and Equipment ( “ ASC 360 ” ). As of September 30, 2021 and December 31, 2020, accumulated depreciation related to furniture, equipment, purchased software and leasehold improvements totaled $51.9 million and $35.4 million, respectively. Depreciation expense for furniture, equipment, purchased software and leasehold improvements was $5.7 million and $4.7 million for the three months ended September 30, 2021 and 2020, respectively, and $16.8 million and $13.3 million for the nine months ended September 30, 2021 and 2020, respectively. Software Development Costs The Company capitalizes costs associated with the development of internal use software at the point at which the conceptual formulation, design and testing of possible software project alternatives have been completed, in accordance with ASC 350, Intangibles – Goodwill and Other ( “ ASC 350 ” ) . The Company capitalizes employee compensation and related benefits and third party consulting costs incurred during the application development stage which directly contribute to such development. Such costs are amortized on a straight-line basis over three years. Software development costs acquired as part of the NFI Acquisition are amortized over one year. Costs capitalized as part of the Refinitiv Transaction pushdown accounting allocation are amortized over nine years. The Company reviews the amounts capitalized for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not be fully recoverable, or that their useful lives are shorter than originally expected. Non-capitalized software costs and routine maintenance costs are expensed as incurred. As of September 30, 2021 and December 31, 2020, accumulated amortization related to software development costs totaled $101.8 million and $67.4 million, respectively. Amortization expense for software development costs was $12.4 million and $9.3 million for the three months ended September 30, 2021 and 2020, respectively, and $34.4 million and $26.1 million for the nine months ended September 30, 2021 and 2020, respectively. Goodwill Goodwill includes the excess of the fair value of the Company above the fair value accounting basis of the net assets and liabilities of the Company as previously applied under pushdown accounting in connection with the Refinitiv Transaction. Goodwill also includes the cost of acquired companies in excess of the fair value of identifiable net assets at the acquisition date, including the NFI Acquisition. Goodwill is not amortized, but in accordance with ASC 350, goodwill is tested for impairment annually on October 1 st and between annual tests, whenever events or changes in circumstances indicate that the carrying amount may not be fully recoverable. Goodwill is tested at the reporting unit level, which is defined as an operating segment or one level below the operating segment. An impairment loss is recognized if the estimated fair value of a reporting unit is less than its net book value. Such loss is calculated as the difference between the estimated fair value of goodwill and its carrying value. Goodwill was last assessed on October 1, 2020 and no impairment of goodwill was identified. Intangible Assets Intangible assets with a finite life are amortized over the estimated lives, ranging from seven As of September 30, 2021 and December 31, 2020, accumulated amortization related to intangible assets totaled $300.1 million and $223.7 million, respectively. Amortization expense for definite-lived intangible assets was $26.8 million and $24.9 million for the three months ended September 30, 2021 and 2020, respectively, and $76.5 million and $74.6 million for the nine months ended September 30, 2021 and 2020, respectively. Equity Investments Without Readily Determinable Fair Values Equity Investments without a readily determinable fair value are measured at cost, less impairment, plus or minus observable price changes (in orderly transactions) of an identical or similar investment of the same issuer. If the Company determines that the equity investment is impaired on the basis of a qualitative assessment, the Company will recognize an impairment loss equal to the amount by which the investment’s carrying amount exceeds its fair value. Equity investments are included as a component of other assets on the condensed consolidated statements of financial condition. Leases The Company has operating leases for corporate offices and data centers with initial lease terms ranging from one The Company adopted Accounting Standards Update (“ASU”) 2016-2, Leases (Topic 842) on January 1, 2019 using the modified retrospective method of adoption and elected to take the optional package of practical expedients, which allowed for no reassessment of: i. whether any expired or existing contracts are or contain leases, ii. the lease classification for any expired or existing leases, and iii. initial direct costs for any existing leases. Deferred IPO and Follow-On Offering Costs Deferred IPO and follow-on offering costs consist of legal, accounting, and other costs directly related to the Company’s efforts to raise capital. In accordance with ASC 505-10-25, Equity , these costs are recognized as a reduction in additional paid-in capital within the condensed consolidated statements of financial condition when the offering is effective. As of both September 30, 2021 and December 31, 2020 , $15.9 million of deferred costs related to the IPO and $5.2 million of deferred costs related to follow-on offerings were included as a component of the additional paid-in capital balance in the condensed consolidated statements of financial condition. No offering costs were incurred during the three and nine months ended September 30, 2021. Translation of Foreign Currency and Foreign Currency Forward Contracts Revenues and expenses denominated in foreign currencies are translated at the rate of exchange prevailing at the transaction date. Assets and liabilities denominated in foreign currencies are translated at the rate prevailing at the condensed consolidated statements of financial condition date. Foreign currency re-measurement gains or losses on transactions in nonfunctional currencies are recognized in the condensed consolidated statements of income within general and administrative expenses. The realized and unrealized losses totaled $0.5 million and $45,000 during the three months ended September 30, 2021 and 2020, respectively, and realized and unrealized gains/losses totaled a $2.5 million loss and a $1.3 million gain during the nine months ended September 30, 2021 and 2020, respectively. Gains or losses on translation in the financial statements of a non-U.S. operation, when the functional currency is other than the U.S. dollar, are included as a component of other comprehensive income. The Company enters into foreign currency forward contracts to mitigate its U.S. dollar and British pound sterling versus Euro exposure, generally with a duration of less than twelve months. The Company’s foreign currency forward contracts are not designated as hedges for accounting purposes and changes in the fair value of these contracts during the period are recognized in the condensed consolidated statements of income within general and administrative expenses. The Company does not use derivative instruments for trading or speculative purposes. Realized and unrea lized gains/losses on foreig n currency forward contracts totaled a $1.3 million gain and a $2.1 million loss during the three months ended September 30, 2021 and 2020, respectively, and realized and unrealized gains/losses on foreign currency forward contracts totaled a $6.2 million gain and a $5.1 million loss during the nine months ended September 30, 2021 and 2020, respectively . See Note 11 – Fair Value of Financial Instruments for additional details on the Company ’ s derivative instruments. Income Tax The Corporation is subject to U.S. federal, state and local income taxes with respect to its taxable income, including its allocable share of any taxable income of TWM LLC, and is taxed at prevailing corporate tax rates. TWM LLC is a multiple member limited liability company taxed as a partnership and accordingly any taxable income generated by TWM LLC is passed through to and included in the taxable income of its members, including the Corporation. Income taxes also include unincorporated business taxes on income earned or losses incurred for conducting business in certain state and local jurisdictions, income taxes on income earned or losses incurred in foreign jurisdictions on certain operations and federal and state income taxes on income earned or losses incurred, both current and deferred, on subsidiaries that are taxed as corporations for U.S. tax purposes. The Company records deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities. The Company measures deferred taxes using the enacted tax rates and laws that will be in effect when such temporary differences are expected to reverse. The Company evaluates the need for valuation allowances based on the weight of positive and negative evidence. The Company records valuation allowances wherever management believes it is more likely than not that the Company will not be able to realize its deferred tax assets in the future. The Company records uncertain tax positions in accordance with ASC 740, Income Taxes, on the basis of a two-step process whereby (i) the Company determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (ii) for those tax positions that meet the more-likely-than-not recognition threshold, the Company recognizes the amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company recognizes interest and penalties related to income taxes within the provision for income taxes in the condensed consolidated statements of income. Accrued interest and penalties are included within accounts payable, accrued expenses and other liabilities in the condensed consolidated statements of financial condition. The Company has elected to treat taxes due on future U.S. inclusions in taxable income under the global intangible low-taxed income (“GILTI”) provision of the Tax Cuts and Jobs Act as a current period expense when incurred. Stock-Based Compensation The Company accounts for stock-based compensation in accordance with ASC 718, Compensation – Stock Compensation (“ASC 718” ) . ASC 718 focuses primarily on accounting for a transaction in which an entity obtains employee services in exchange for stock-based payments. Under ASC 718, the stock-based payments received by the employees of the Company are accounted for either as equity awards or as liability awards. As an equity award, the Company measures and recognizes the cost of employee services received in exchange for awards of equity instruments based on their estimated fair values measured as of the grant date. These costs are recognized as an expense over the requisite service period, with an offsetting increase to additional paid-in capital. As a liability award, the cost of employee services received in exchange for an award of equity instruments is generally measured based on the grant-date fair value of the award. The fair value of that award is remeasured subsequently at each reporting date through the settlement. Changes in the equity instrument’s fair value during the requisite service period are recognized as compensation cost over that period. For periods following the Reorganization Transactions and the IPO, the fair value of new equity instrument grants is determined based on the price of the Class A common stock on the grant date. Under ASC 718, the grant-date fair value of stock-based awards that do not require future service (i.e., vested awards) are expensed immediately. The grant-date fair value of stock-based awards that require future service, and are graded-vesting awards, are amortized over the relevant service period on a straight-line basis, with each tranche separately measured. The grant-date fair value of stock-based awards that require both future service and the achievement of Company performance-based conditions, are amortized over the relevant service period for the performance-based condition. If in a reporting period it is determined that the achievement of a performance target for a performance-based tranche is not probable, then no expense is recognized for that tranche and any expenses already recognized relating to that tranche in prior reporting periods are reversed in the current reporting period. Prior to the IPO, the Company awarded options to management and other employees (collectively, the “Special Option Award”) under the Amended and Restated Tradeweb Markets Inc. Option Plan (the “Option Plan”). In accounting for the options issued under the Option Plan, compensation expense is measured and recognized for all awards based on their estimated fair values measured as of the grant date. Costs related to these options are recognized as an expense in the condensed consolidated statements of income over the requisite service period, with an offsetting increase to additional paid-in capital. The non-cash stock-based compensation expense associated with the Special Option Award began being expensed in the second quarter of 2019. Determining the appropriate fair value model and calculating the fair value of the stock-based awards requires the input of highly subjective assumptions, including the expected life of the stock-based awards and the stock price volatility. The Company uses the Black-Scholes pricing model to value some of its stock-based awards. Earnings Per Share Basic earnings per share is computed by dividing the net income attributable to the Company’s shares by the weighted-average number of the Company’s shares outstanding during the period. For purposes of computing diluted earnings per share, the weighted-average number of the Company’s shares reflects the dilutive effect that could occur if securities that qualify as participating securities were converted into or exchanged or exercised for TWM LLC’s shares, in the pre-IPO period, and the Class A or Class B common stock, in the post-IPO period, using the treasury stock method, as applicable. Shares of Class C and Class D common stock do not have economic rights in Tradeweb Markets Inc. and, therefore, are not included in the calculation of basic earnings per share. Fair Value Measurement The fair value of a financial instrument is the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (the exit price). Instruments that the Company owns (long positions) are marked to bid prices, and instruments that the Company has sold, but not yet purchased (short positions) are marked to offer prices. Fair value measurements do not include transaction costs. The fair value hierarchy under ASC 820, Fair Value Measurement (“ASC 820”) , prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1 measurements) and the lowest priority to unobservable inputs (level 3 measurements). The three levels of the fair value hierarchy under ASC 820 are described below. Basis of Fair Value Measurement A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. • Level 1 : Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2 : Quoted prices in markets that are not considered to be active or financial instruments for which all significant inputs are observable, either directly or indirectly; • Level 3 : Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

Restricted Cash

Restricted Cash	9 Months Ended
	Sep. 30, 2021
Restricted Cash Equivalents [Abstract]
Restricted Cash	Restricted CashCash has been segregated in a special reserve bank account for the benefit of brokers and dealers under SEC Rule 15c3-3. The Company computes the proprietary accounts of other broker-dealers (“PAB”) reserve, which requires the Company to maintain minimum segregated cash in the amount of total credits per the reserve computation. As of both September 30, 2021 and December 31, 2020, cash in the amount of $1.0 million has been segregated in the PAB reserve account, exceeding the requirements pursuant to SEC Rule 15c3-3.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Acquisitions	AcquisitionsOn June 25, 2021, the Company completed its acquisition of all of the outstanding equity interests of Execution Access, LLC, Kleos Managed Services Holdings, LLC and Kleos Managed Services, L.P., which collectively represented the NFI Acquisition. The all-cash purchase price of $190.0 million is net of cash acquired, net of deposits with clearing organizations acquired and prior to working capital adjustments. At closing, preliminary working capital adjustments resulted in a $0.7 million increase to the purchase price. Working capital adjustments are expected to be finalized during the fourth quarter of 2021. Execution Access, LLC is a limited liability company organized in the state of Delaware and is a broker-dealer registered with the SEC and FINRA. The platform (formerly known as eSpeed) acquired from Nasdaq is a fully executable central order limit book (CLOB) for electronic trading in on-the-run (OTR) U.S. government bonds. The acquisition was accounted for as a business combination and the Company utilized the assistance of a third-party valuation specialist to determine the fair value of the assets acquired and liabilities assumed at the date of acquisition. The fair values were determined based on assumptions that reasonable market participants would use in the principal (or most advantageous) market and primarily included significant unobservable inputs (Level 3). Customer relationships were valued using the income approach, specifically a multi-period excess earnings method. The excess earnings method examines the economic returns contributed by the identified tangible and intangible assets of a company, and then examines the excess return that is attributable to the intangible asset being valued. The discount rate used reflects the amount of risk associated with the hypothetical cash flows for the customer relationships relative to the overall business. In developing a discount rate for the customer relationships, the Company estimated a weighted-average cost of capital for the overall business and employed an intangible asset risk premium to this rate when discounting the excess earnings related to customer relationships. The resulting discounted cash flows were then tax-affected at the applicable statutory rate. A discounted tax amortization benefit was also added to the fair value of the assets under the assumption that the customer relationships would be amortized for tax purposes over a period of 15 years . The preliminary purchase price was allocated as follows: Purchase Price Allocation (in thousands) Cash and cash equivalents $ 33,806 Deposits with clearing organizations 18,147 Accounts receivable 2,779 Equipment 1,498 Software development costs 820 Goodwill 87,981 Intangible assets – customer relationships 99,236 Other assets 897 Accrued compensation (1,289) Deferred revenue (620) Accounts payable, accrued expenses and other liabilities (592) Total 242,663 Less: Cash acquired (33,806) Less: Deposits with clearing organizations acquired (18,147) Less: Preliminary working capital adjustments (710) Purchase price, net of cash and deposits acquired and excluding working capital adjustments $ 190,000 The areas of the preliminary purchase price allocation that are not yet finalized as of September 30, 2021, relate primarily to the valuation of the identifiable intangible assets and software and final working capital adjustments. The allocation of the purchase price will be finalized upon completion of the analysis of the acquired assets within one year of the date of acquisition. For GAAP purposes, the acquired software development costs will be amortized over a useful life of one year and the customer relationships will be amortized over a useful life of 13 years. The goodwill recognized in connection with the NFI Acquisition is primarily attributable to the acquisition of an assembled workforce and expected synergies from the integration of the operations of the NFI Acquisition into the Company’s operations and its single business segment. All of the goodwill recognized in connection with the NFI Acquisition is expected to be deductible for income tax purposes. During the three and nine months ended September 30, 2021, the Company recognized $0.1 million and $4.8 million, respectively, in transaction costs incurred to effect the NFI Acquisition, which are included as a component of professional fees in the accompanying condensed consolidated statements of income.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Revenue Recognition The Company earns transaction fees from transactions executed on the Company’s trading platforms through various fee plans. Transaction fees are generated both on a variable and fixed price basis and vary by geographic region, product type and trade size. For variable transaction fees, the Company charges clients fees based on the mix of products traded and the volume of transactions executed. Transaction fee revenue is recognized and recorded on a trade-date basis and is generally billed monthly. The Company earns commission revenue from its electronic and voice brokerage services on a riskless principal basis. Riskless principal revenues are derived on matched principal transactions where revenues are earned on the spread between the buy and sell price of the transacted product. Securities transactions and related commission income for brokerage transactions are recognized and recorded on a trade-date basis. Commission revenue is collected by the Company when the trade settles or is billed monthly. The Company earns subscription fees from granting access to institutional investors to the Company’s electronic marketplaces. Subscription fees are recognized into income in the period that access is provided on a monthly basis. Also included in subscription fees are viewer fees earned monthly from institutional investors accessing fixed income market data. The frequency of subscription fee billings varies from monthly to annually, depending on contract terms. Fees received by the Company which are not yet earned are included in deferred revenue on the condensed consolidated statements of financial condition until the revenue recognition criteria has been met. The Company earns fees from Refinitiv relating to the sale of market data to Refinitiv, which redistributes that data. Included in these fees, which are billed quarterly, are real-time market data fees which are recognized in the period that the data is provided, generally on a monthly basis, and historical data sets which are recognized when the historical data set is provided to Refinitiv. Significant judgements used in accounting for this contract include: • The provision of real-time market data feeds and annual historical data sets are distinct performance obligations. • The performance obligations under this contract are recognized over time from the initial delivery of the data feeds or each historical data set until the end of the contract term. • Determining the transaction price for the performance obligations by using a market assessment analysis. Inputs in this analysis include a consultant study which determined the overall value of the Company’s market data and pricing information for historical data sets provided by other companies. Some revenues earned by the Company have fixed fee components, such as monthly minimums or fixed monthly fees, and variable components, such as transaction based fees. The breakdown of revenues between fixed and variable revenues for the three and nine months ended September 30, 2021 and 2020 is as follows: Three Months Ended Three Months Ended September 30, 2021 September 30, 2020 (in thousands) (in thousands) Variable Fixed Variable Fixed Revenues Transaction fees and commissions $ 167,437 $ 38,879 $ 123,619 $ 36,556 Subscription fees (1) 445 55,947 400 50,090 Other 181 2,436 117 2,088 Total revenue $ 168,063 $ 97,262 $ 124,136 $ 88,734 (1) Fixed subscription fees for the three months ended September 30, 2021 and 2020 include $15.0 million and $14.3 million, respectively, of Refinitiv market data fees. Nine Months Ended Nine Months Ended September 30, 2021 September 30, 2020 (in thousands) (in thousands) Variable Fixed Variable Fixed Revenues Transaction fees and commissions $ 513,759 $ 115,754 $ 395,927 $ 107,826 Subscription fees (1) 1,367 160,819 1,280 147,892 Other 611 7,254 464 6,194 Total revenue $ 515,737 $ 283,827 $ 397,671 $ 261,912 (1) Fixed subscription fees for the nine months ended September 30, 2021 and 2020 include $45.0 million and $43.5 million respectively, of Refinitiv market data fees. Deferred Revenue The Company records deferred revenue when cash payments are received or due in advance of services to be performed. The revenue recognized and the remaining deferred revenue balance are shown below: Amount (in thousands) Deferred revenue balance - December 31, 2020 $ 23,193 New billings 91,402 Revenue recognized (85,435) Deferred revenue acquired in connection with the NFI Acquisition 620 Deferred revenue balance - September 30, 2021 $ 29,780 During the nine months ended September 30, 2021, the Company recognized $22.7 million in total revenue that was deferred as of December 31, 2020. During the nine months ended September 30, 2020, the Company recognized $23.4 million in total revenue that was deferred as of December 31, 2019.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s provision for income taxes includes U.S. federal, state, local and foreign taxes. The Company’s effective tax rate for the three months ended September 30, 2021 and 2020 was approximately 23.3% an d 19.1%, respectively. The Company’s effective tax rate for the nine months ended September 30, 2021 and 2020 was approximate ly 20.0% an d 20.8%, respectively. The effective tax rate for the three months ended September 30, 2021 differed from the U.S. federal statutory rate of 21.0% primarily due to state, local and foreign taxes and the return-to-provision adjustment, partially offset by effect of non-controlling interests and the tax impact of the issuance of common stock from equity incentive plans. The effective tax rate for the three months ended September 30, 2020 differed from the U.S. federal statutory rate of 21.0% primarily due to the effect of non-controlling interests and the tax impact of the issuance of common stock from equity incentive plans, partially offset by state, local and foreign taxes. The effective tax rate for the nine months ended September 30, 2021 and 2020 differed from the U.S. federal statutory rate of 21.0% primarily due to the effect of non-controlling interests and the tax impact of the issuance of common stock from equity incentive plans, partially offset by state, local and foreign taxes. As a result of the Reorganization Transactions, the Corporation is subject to U.S. federal, state and local income taxes with respect to its taxable income, including its allocable share of any taxable income of TWM LLC, and is taxed at prevailing corporate tax rates. The Company’s actual effective tax rate will be impacted by the Corporation’s ownership share of TWM LLC, which will increase over time primarily as the Continuing LLC Owners redeem or exchange their LLC Interests for shares of Class A common stock or Class B common stock, as applicable, or the Corporation purchases LLC Interests from the Continuing LLC Owners. The Company’s consolidated effective tax rate will vary from period to period depending on redemptions, exchanges or purchases of LLC Interests as described above, changes in the geographic mix of its earnings and changes in tax legislation and tax rates in various jurisdictions. As a result of the Refinitiv Contribution, the Company assumed the tax liabilities of the contributed entity. The contributed entity is under audit by the State of New Jersey for the tax years 2012 – 2015 and is appealing a tax assessment from an audit by the State of New Jersey for the tax years 2008 – 2011. As of both September 30, 2021 and December 31, 2020, the tax liability related to the Refinitiv Contribution was $2.7 million and is included within accounts payable, accrued expenses and other liabilities on the condensed consolidated statement of financial condition. The Company is indemnified by Refinitiv for tax liabilities that were assumed by the Company as a result of the Refinitiv Contribution. As of both September 30, 2021 and December 31, 2020 , $2.7 million is included in other as

Tax Receivable Agreement

Tax Receivable Agreement	9 Months Ended
	Sep. 30, 2021
Tax Receivable Agreement
Tax Receivable Agreement	Tax Receivable Agreement In connection with the Reorganization Transactions, the Corporation entered into a tax receivable agreement (the “Tax Receivable Agreement”) with TWM LLC and the Continuing LLC Owners, which provides for the payment by the Corporation to a Continuing LLC Owner of 50% of the amount of U.S. federal, state and local income or franchise tax savings, if any, that the Corporation actually realizes (or in some circumstances is deemed to realize) as a result of (i) increases in the tax basis of TWM LLC’s assets resulting from (a) the purchase of LLC Interests from such Continuing LLC Owner, including with the net proceeds from the IPO and any subsequent offerings or (b) redemptions or exchanges by such Continuing LLC Owner of LLC Interests for shares of Class A common stock or Class B common stock or for cash, as applicable, and (ii) certain other tax benefits related to the Corporation making payments under the Tax Receivable Agreement. Payments under the Tax Receivable Agreement are made within 150 days after the filing of the tax return based on the actual tax savings realized by the Corporatio n. The first payment of the Tax Receivable Agreement was made in January 2021. Substantially all payments due under the Tax Receivable Agreement are payable over the fifteen years following the purchase of LLC Interests from Continuing LLC Owners or redemption or exchanges by Continuing LLC Owners of LLC Interests. The Corporation accounts for the income tax effects resulting from taxable redemptions or exchanges of LLC Interests by the Continuing LLC Owners for shares of Class A common stock or Class B common stock or cash, as the case may be, and purchases by the Corporation of LLC Interests from the Continuing LLC Owners by recognizing an increase in deferred tax assets, based on enacted tax rates at the date of each redemption, exchange, or purchase, as the case may be. Further, the Corporation evaluates the likelihood that it will realize the benefit represented by the deferred tax asset, and, to the extent that the Corporation estimates that it is more likely than not that it will not realize the benefit, it reduces the carrying amount of the deferred tax asset with a valuation allowance. The impact of any changes in the projected obligations under the Tax Receivable Agreement as a result of changes in the mix of the Company’s earnings, tax legislation and tax rates in various jurisdictions, or other factors that may impact the Corporation’s tax savings, are reflected in income before taxes on the condensed consolidated statement of income in the period in which the change occurs. As of September 30, 2021 and December 31, 2020 , the tax receivable agreement liability on the condensed consolidated statements of financial condition totaled $425.2 million and $404.3 million, respectively.

Non-Controlling Interests

Non-Controlling Interests	9 Months Ended
	Sep. 30, 2021
Noncontrolling Interest [Abstract]
Non-Controlling Interests	Non-Controlling Interests In connection with the Reorganization Transactions, Tradeweb Markets Inc. became the sole manager of TWM LLC and, as a result of this control, and because Tradeweb Markets Inc. has a substantial financial interest in TWM LLC, consolidates the financial results of TWM LLC into its condensed consolidated financial statements. The non-controlling interests balance reported on the condensed consolidated statements of financial condition represents the economic interests of TWM LLC held by the holders of LLC Interests other than Tradeweb Markets Inc. Income or loss is attributed to the non-controlling interests based on the relative ownership percentages of LLC Interests held during the period by Tradeweb Markets Inc. and the other holders of LLC Interests. The following table summarizes the ownership interest in Tradeweb Markets LLC: September 30, 2021 September 30, 2020 LLC Ownership LLC Ownership Number of LLC Interests held by Tradeweb Markets Inc. 202,194,257 86.9 % 187,918,774 82.6 % Number of LLC Interests held by non-controlling interests 30,531,933 13.1 % 39,513,246 17.4 % Total LLC Interests outstanding 232,726,190 100.0 % 227,432,020 100.0 % LLC Interests held by the Continuing LLC Owners are redeemable in accordance with the TWM LLC Agreement at the election of the members for shares of Class A common stock or Class B common stock, on a one-for-one basis or, at the Company’s option, a cash payment in accordance with the terms of the TWM LLC Agreement. The following table summarizes the impact on Tradeweb Market Inc.'s equity due to changes in the Corporation’s ownership interest in TWM LLC: Net Income Attributable to Tradeweb Markets Inc. and Transfers (to) from the Non-Controlling Interests Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Net income attributable to Tradeweb Markets Inc. $ 54,763 $ 36,812 $ 177,938 $ 111,236 Transfers (to) from non-controlling interests: Increase/(decrease) in Tradeweb Markets Inc.'s additional paid-in capital as a result of ownership changes in TWM LLC (16) (1,478) 85,446 423,581 Net transfers (to) from non-controlling interests (16) (1,478) 85,446 423,581 Change from net income attributable to Tradeweb Markets Inc. and transfers (to) from non-controlling interests $ 54,747 $ 35,334 $ 263,384 $ 534,817

Stockholders' Equity and Stock-

Stockholders' Equity and Stock-Based Compensation Plans	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stockholders' Equity and Stock-Based Compensation Plans	Stockholders' Equity and Stock-Based Compensation Plans The rights and privileges of the Company’s stockholders’ equity and LLC Interests are described in the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 and there have been no changes to those rights and privileges during the nine months ended September 30, 2021. April 2020 Follow-On Offering In the second quarter of 2020, Tradeweb Markets Inc. completed an underwritten follow-on offering of 12,835,245 shares of Class A Common stock at a public offering price of $50.25 per share, which included 1,674,162 shares of Class A common stock issued pursuant to the underwriters’ option to purchase additional shares of Class A common stock. Tradeweb Markets Inc. received net proceeds of $626.3 million, after deducting underwriting discounts and commissions but before deducting estimated offering expenses, which were used to purchase (i) 12,238,827 issued and outstanding LLC Interests from certain of the Bank Stockholders and certain of our executive officers (and the corresponding shares of Class C common stock and/or Class D common stock held by such holders were cancelled) and (ii) 596,418 issued and outstanding shares of Class A common stock from certain of our executive officers (which shares of Class A common stock were cancelled), at a purchase price per interest and share equal to the public offering price of $50.25, less the underwriting discounts and commissions payable thereon. Stock-Based Compensation Plans Under the Tradeweb Markets Inc. 2019 Omnibus Equity Incentive Plan, the Company is authorized to issue up to 8,841,864 new shares of Class A common stock to employees, officers and non-employee directors. Under this plan, the Company may grant awards in respect of shares of Class A common stock, including performance-based restricted stock units (“PRSUs”), stock options, restricted stock units (“RSUs”) and dividend equivalent rights. The awards may have performance-based and/or time-based vesting conditions. RSUs and PRSUs each represent promises to issue actual shares of Class A common stock at the end of a vesting period. Stock options have a maximum contractual term of 10 years. On August 30, 2021, the Company’s Board of Directors appointed Sara Furber to serve as the Company’s new Chief Financial Officer (“CFO”), effective September 7, 2021. In connection with her employment offer, Ms. Furber was granted 44,589 RSUs with a grant date fair value of $3.6 million ($80.78 per share) of which 19,350, 16,672, 4,948 and 3,619 RSUs will vest on March 31, 2022, 2023, 2024 and 2025, respectively. Ms. Furber was also granted 4,270 target PRSUs valued on the date of grant at $80.78 per share. The number of PRSUs that will ultimately vest on January 1, 2024 will be determined by a performance modifier, which is adjusted based on the Company’s financial performance for the year ended December 31, 2021 and can vary between 0% (minimum) and 200% (maximum) of the target (100%) award amount. The RSUs and PRSUs granted to Ms. Furber in connection with her employment offer are collectively referred to as the “CFO Special Equity Awards.” During the three months ended September 30, 2021, the Company incurred a total of $0.4 million in stock-based compensation expense relating to the CFO Special Equity Awards. Ms. Furber succeeds Robert Warshaw, the Company’s former CFO, who will leave the Company following a period of transition ending on January 4, 2022 (the “CFO Transition Period”). As of August 30, 2021, there was approximately $1.8 million in unamortized stock-based compensation expense associated with equity awards previously granted to Mr. Warshaw that will be accelerated and amortized into expense over a revised estimated service period ending on January 4, 2022 (the “Former CFO Accelerated Stock-based Compensation Expense”). During the three months ended September 30, 2021, the Company incurred a total of $0.5 million in expense relating to the Former CFO Accelerated Stock-based Compensation Expense. In addition to the CFO Special Equity Awards discussed above, during the three months ended September 30, 2021, the Company granted 4,542 RSUs at a weighted-average grant-date fair value of $84.99 and during the nine months ended September 30, 2021, the Company granted 325,717 RSUs and 205,655 PRSUs at a weighted-average grant-date fair value of $74.31 and $74.16, respectively. These RSU awards granted to employees will vest one-third each year over a three-year period, and RSU awards granted to non-employee directors will vest after one year. These PRSUs vest at the end of a three-year cliff vesting period and the number of shares a participant will receive upon vesting is determined by a performance modifier, which is adjusted as a result of the financial performance of the Company in the grant year. The performance modifier can vary between 0% (minimum) and 200% (maximum) of the target (100%) award amount. A summary of the Company ’ s total stock-based compensation expense, including expense associated with the CFO Special Equity Awards and the Former CFO Accelerated Stock-based Compensation Expense, is presented below: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Total stock-based compensation expense $ 13,776 $ 9,757 $ 36,943 $ 28,074 Share Repurchase Program On February 4, 2021, the Company announced that the board of directors authorized a new share repurchase program, primarily to offset annual dilution from stock-based compensation plans (the “Share Repurchase Program”). The Share Repurchase Program authorizes the purchase of up to $150.0 million of the Company’s Class A common stock at the Company’s discretion through the end of fiscal year 2023. The Share Repurchase Program will be effected primarily through regular open-market purchases (which may include repurchase plans designed to comply with Rule 10b5-1). The amounts and timing of the repurchases will be subject to general market conditions and the prevailing price and trading volumes of our Class A common stock. The Share Repurchase Program does not require the Company to acquire a specific number of shares and may be suspended, amended or discontinued at any time. For shares repurchased pursuant to the Share Repurchase Program, the excess of the repurchase price paid over the par value of the Class A common stock will be recorded as a reduction to retained earnings. The Company began buying back shares pursuant to the Share Repurchase Program during the second quarter of 2021. During the three months ended September 30, 2021, the Company acquired a total of 140,169 shares of Class A common stock, at an average price of $85.61, for purchases totaling $12.0 million. During the nine months ended September 30, 2021, the Company acquired a total of 757,813 shares of Class A common stock, at an average price of $84.03, for purchases totaling $63.7 million. Each share of Class A common stock repurchased pursuant to the Share Repurchase Program was funded with the proceeds, on a dollar-for-dollar basis, from the repurchase by Tradeweb Markets LLC of an LLC Interest from the Company in order to maintain the one-to-one ratio between shares of the Company’s common stock and the LLC Interests. Subsequent to their repurchase, the shares of Class A common stock and the LLC Interests were all cancelled and retired. As of September 30, 2021, a total of $86.3 million remained available for repurchase pursuant to the Share Repurchase Program. Other Share Repurchases During the three months ended September 30, 2021 and 2020, the Company withheld 36,888 and 3,171 shares, respectively, of common stock from employee stock option, PRSU and RSU awards, at an average price per share of $85.10 and $56.65, respectively, and an aggregate value of $3.1 million and $0.2 million, respectively, based on the price of the Class A common stock on the date the relevant withholding occurred. During the nine months ended September 30, 2021 and 2020, the Company withheld 831,738 and 1,442,155 shares, respectively, of common stock from employee stock option, PRSU and RSU awards, at an average price per share of $68.02 and $49.82, respectively, and an aggregate value of $56.6 million and $71.8 million, respectively, based on the price of the Class A common stock on the date the relevant withholding occurred.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company enters into transactions with its affiliates from time to time which are considered to be related party transactions. Prior to the Reorganization Transactions, the Bank Stockholders were collectively considered to be related parties of the Company. As a result of the Reorganization Transactions, they are no longer considered to be related parties. As of September 30, 2021 and December 31, 2020, the following balances with such affiliates were included in the condensed consolidated statements of financial condition in the following line items: September 30, December 31, 2021 2020 (in thousands) Accounts receivable $ 175 $ 4,009 Receivable from affiliates 2,806 111 Other assets 2,722 2,722 Accounts payable, accrued expenses and other liabilities 7,637 6,140 Deferred revenue 4,500 4,500 Payable to affiliates 3,390 5,142 The following balances with such affiliates were included in the condensed consolidated statements of income in the following line items: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Revenue: Subscription fees $ 223 $ — $ 998 $ — Refinitiv market data fees (1) 15,002 14,273 45,045 43,466 Other fees 120 — 403 — Expenses: (2) Employee compensation and benefits 293 — 293 — Technology and communications 1,027 740 2,507 2,220 General and administrative 224 — 228 (596) Professional fees 15 — 15 — Occupancy — — — 15 (1) The Company maintains a market data license agreement with Refinitiv. Under the agreement, the Company delivers to Refinitiv certain market data feeds which Refinitiv redistributes to its customers. The Company earns license fees and royalties for these feeds. (2) The Company maintains agreements with Refinitiv to provide the Company with certain real estate, payroll, benefits administration and other administrative services. During the three months ended September 30, 2021, $1.6 million of previously accrued expenses payable to affiliates of Refinitiv were waived and the liabilities were reversed through an increase to additional paid-in capital. The Company engaged Blackstone Advisory Partners L.P., an affiliate of Blackstone, to provide certain financial consulting services in connection with the IPO, the October 2019 follow-on offering and the April 2020 follow-on offering for fees of $1.0 million, $0.5 million, and $0.5 million, respectively, which fees, with respect to the October 2019 follow-on offering and the April 2020 follow-on offering, were reimbursed by the underwriters. As of both September 30, 2021 and December 31, 2020, $2.0 million related to these offering costs, is included as a component of the additional paid-in capital balance on the condensed consolidated statements of financial condition.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments Financial Instruments Measured at Fair Value The Company’s financial instruments measured at fair value on the condensed consolidated statements of financial condition as of September 30, 2021 and December 31, 2020 have been categorized based upon the fair value hierarchy as follows: Quoted Prices in active Markets for Identical Assets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (in thousands) As of September 30, 2021 Assets Cash equivalents – Money market funds $ 410,709 $ — $ — $ 410,709 Receivable from affiliates – Foreign currency forward contracts — 2,642 — 2,642 Total assets measured at fair value $ 410,709 $ 2,642 $ — $ 413,351 Liabilities Payable to affiliates – Foreign currency forward contracts $ — $ — $ — $ — Total liabilities measured at fair value $ — $ — $ — $ — As of December 31, 2020 Assets Cash equivalents – Money market funds $ 541,790 $ — $ — $ 541,790 Total assets measured at fair value $ 541,790 $ — $ — $ 541,790 Liabilities Payable to affiliates – Foreign currency forward contracts $ — $ 3,409 $ — $ 3,409 Total liabilities measured at fair value $ — $ 3,409 $ — $ 3,409 The Company ’ s money market funds are classified within level 1 of the fair value hierarchy because they are valued using quoted market prices in active markets. The valuation for the Company’s foreign currency forward contracts is primarily based on the difference between the exchange rate associated with the forward contract and the exchange rate at the current period end. Foreign currency forward contracts are categorized as Level 2 in the fair value hierarchy. The Company enters into foreign currency forward contracts to mitigate its U.S. dollar and British pound sterling versus Euro exposure, generally with a duration of less than twelve months. As of September 30, 2021 and December 31, 2020 , the counterparty on each of the foreign currency forward contracts was an affiliate of Refinitiv and therefore the corresponding receivables and liabilities on such contracts were included in receivable from affiliates and payable to affiliates on the accompanying condensed consolidated statements of financial condition. The following table summarizes the aggregate U.S. dollar equivalent notional amount of the Company ’ s foreign currency forward contracts not designated as hedges for accounting purposes: September 30, December 31, 2021 2020 (in thousands) Foreign currency forward contracts – Gross notional amount $ 122,744 $ 122,458 The Company’s foreign currency forward contracts are not designated as hedges for accounting purposes and changes in the fair value of these contracts during the period are recognized in the condensed consolidated statements of income within general and administrative expenses. The total realized and unrealized gains (losses) on foreign currency forward contracts recorded within general and administrative expenses in the condensed consolidated statements of income are as follows: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Foreign currency forward contracts not designated in accounting hedge relationship $ 1,262 $ (2,124) $ 6,223 $ (5,087) The Company has no financial instruments measured at fair value that are classified within level 3 of the fair value hierarchy. Financial Instruments Not Measured at Fair Value The Company’s financial instruments not measured at fair value on the condensed consolidated statements of financial condition as of September 30, 2021 and December 31, 2020 have been categorized based upon the fair value hierarchy as follows: Carrying Value Quoted Prices in Significant Observable Inputs (Level 2) Significant Total Fair Value As of September 30, 2021 (in thousands) Assets Cash and restricted cash $ 412,196 $ 412,196 $ — $ — $ 412,196 Receivable from brokers and dealers and clearing organizations 33,950 — 33,950 — 33,950 Deposits with clearing organizations 24,396 24,396 — — 24,396 Accounts receivable 133,351 — 133,351 — 133,351 Other assets – Memberships in clearing organizations 2,392 — — 2,392 2,392 Total $ 606,285 $ 436,592 $ 167,301 $ 2,392 $ 606,285 Liabilities Payable to brokers and dealers and clearing organizations $ 33,828 $ — $ 33,828 $ — $ 33,828 Total $ 33,828 $ — $ 33,828 $ — $ 33,828 As of December 31, 2020 Assets Cash and restricted cash $ 250,490 $ 250,490 $ — $ — $ 250,490 Receivable from brokers and dealers and clearing organizations 368 — 368 — 368 Deposits with clearing organizations 11,671 11,671 — — 11,671 Accounts receivable 105,286 — 105,286 — 105,286 Other assets – Memberships in clearing organizations 1,586 — — 1,586 1,586 Total $ 369,401 $ 262,161 $ 105,654 $ 1,586 $ 369,401 Liabilities Payable to brokers and dealers and clearing organizations $ 252 $ — $ 252 $ — $ 252 Total $ 252 $ — $ 252 $ — $ 252 The carrying value of financial instruments not measured at fair value classified within level 1 or level 2 of the fair value hierarchy approximates fair value because of the relatively short term nature of the underlying assets or liabilities. The memberships in clearing organizations, which are included in other assets on the condensed consolidated statements of financial condition, are classified within level 3 of the fair value hierarchy because the valuation requires assumptions that are both significant and unobservable. Non-recurring Fair Value Measurements We measure certain assets and liabilities, such as assets acquired in a business combination, at fair value as of the acquisition date. See Note 4 – Acquisitions for further details regarding these non-recurring fair value measurements. Financial Instruments Without Readily Determinable Fair Values Included in other assets on the condensed consolidated statements of financial condition are equity investments without readily determinable fair values of $21.1 million at both September 30, 2021 and December 31, 2020, respectively. There were no impairments or adjustments to the carrying value of equity investments without readily determinable fair values during the three and nine months ended September 30, 2021 and 2020 and no adjustments to the original cost basis have been made to the carrying value over the life of the instruments.

Credit Risk

Credit Risk	9 Months Ended
	Sep. 30, 2021
Risks and Uncertainties [Abstract]
Credit Risk	Credit Risk In the normal course of business the Company, as agent, executes transactions with, and on behalf of, other brokers and dealers. If the agency transactions do not settle because of failure to perform by either counterparty, the Company may be obligated to discharge the obligation of the non-performing party and, as a result, may incur a loss if the market value of the security is different from the contract amount of the transaction. A substantial number of the Company’s transactions are collateralized and executed with, and on behalf of, a limited number of broker-dealers. The Company’s exposure to credit risk associated with the nonperformance of these clients in fulfilling their contractual obligations pursuant to securities transactions can be directly impacted by volatile trading markets which may impair the clients’ ability to satisfy their obligations to the Company. From time to time, the Company enters into agreements to repurchase to facilitate the clearance of securities. Credit exposure related to these agreements to repurchase, including the risk related to a decline in market value of collateral (pledged or received), is managed by entering into agreements to repurchase with overnight or short-term maturity dates and only entering into repurchase transactions with netting members of the Fixed Income Clearing Corporation (“FICC”). The FICC requires dealer netting members to maintain a minimum of $25.0 million in equity capital and $10.0 million in excess net capital (as defined in Rule 15c3-1 under the Securities Exchange Act of 1934). The FICC operates a continuous net settlement system, whereby as trades are submitted and compared the FICC becomes the counterparty. The FICC also marks to market collateral on a daily basis, requiring member firms to pay or receive margin amounts as part of their daily funds settlement. The Company does not expect nonperformance by counterparties in the above situations. However, the Company’s policy is to monitor its market exposure and counterparty risk. In addition, the Company has a policy of reviewing, as considered necessary, the credit standing of each counterparty with which it conducts business. Allowance for Credit Losses The Company may be exposed to credit risk regarding its receivables, which are primarily receivables from financial institutions, including investment managers and broker-dealers. As of September 30, 2021 and December 31, 2020, the Company maintained an allowance for credit losses with regard to these receivables of $0.3 million and $0.2 million, respectively. For the three and nine months ended September 30, 2021, credit loss expense was recognized totaling $110,000 and $4,000, respectively. For the three months ended September 30, 2020 credit loss expense was recognized totaling $18,000. For the nine months ended September 30, 2020, recoveries resulted in a reversal of credit loss expense totaling $11,000. The Company maintains an allowance for credit losses based upon an estimate of the amount of potential credit losses in existing accounts receivable, as determined from a review of aging schedules, past due balances, historical collection experience and other specific account data. Careful analysis of the financial condition of our counterparties is also performed. The Company has evaluated its loss assumptions as a result of the COVID-19 pandemic and determined the current estimate of expected credit losses remains reasonable due to continued strong collections and no deterioration in the accounts receivable aging. Account balances are pooled based on the following risk characteristics: 1. Geographic location 2. Transaction fee type (billing type) 3. Legal entity Write-Offs Once determined uncollectible, aged balances are written off as credit loss expense. This determination is based on careful analysis of individual receivables and aging schedules, which are disaggregated based on the risk characteristics described above. Based on current policy, this generally occurs when the receivable is 360 days past due.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies In the normal course of business, the Company enters into user agreements with its dealers which provide the dealers with indemnification from third parties in the event that the electronic marketplaces of the Company infringe upon the intellectual property or other proprietary right of a third party. The Company’s exposure under these user agreements is unknown as this would involve estimating future claims against the Company which have not yet occurred. However, based on its experience, the Company expects the risk of a material loss to be remote. The Company has been named as a defendant, along with other financial institutions, in antitrust class actions (consolidated into two actions) relating to trading practices in United States Treasury securities auctions. The cases were dismissed in March 2021, with the Court granting the Plaintiffs leave to further amend the complaint by no later than May 14, 2021. The plaintiffs filed an Amended Complaint on or about May 14, 2021, and the Company served its motion to dismiss on Plaintiffs on June 14, 2021. The Company believes that it has meritorious defenses to the Amended Complaint and intends to continue to vigorously defend its position. The motions to dismiss were fully briefed on August 4, 2021. Additionally, the Company was dismissed from a class action relating to an interest rate swaps matter in 2017, but that matter continues against the remaining defendant financial institutions. The Company records its best estimate of a loss, including estimated defense costs, when the loss is considered probable and the amount of such loss can be reasonably estimated. Based on its experience, the Company believes that the amount of damages claimed in a legal proceeding is not a meaningful indicator of the potential liability. At this time, the Company cannot reasonably predict the timing or outcomes of, or estimate the amount of loss, or range of loss, if any, related to its pending legal proceedings, including the matters described above, and therefore does not have any contingency reserves established for any of these matters. Revolving Credit Facility On April 8, 2019, the Company entered into a five year, $500.0 million senior secured revolving credit facility (“Credit Facility”) with a syndicate of banks. The Credit Facility was subsequently amended on November 7, 2019. The Credit Facility provides additional borrowing capacity to be used to fund ongoing working capital needs, letters of credit and for general corporate purposes, including potential future acquisitions and expansions. Under the terms of the credit agreement that governs the Credit Facility, borrowings under the Credit Facility bear interest at a rate equal to, at the Company’s option, either (a) a base rate equal to the greatest of (i) the administrative agent’s prime rate, (ii) the federal funds effective rate plus ½ of 1.0% and (iii) one month LIBOR plus 1.0%, in each case plus 0.75%, or (b) LIBOR plus 1.75%, subject to a 0.00% floor. The credit agreement also includes a commitment fee of 0.25% for available but unborrowed amounts and other administrative fees that are payable quarterly. The Credit Facility is available until April 2024, provided the Company is in compliance with all covenants. Financial covenant requirements include maintaining minimum ratios related to interest coverage and leverage.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table summarizes the calculations of basic and diluted earnings per share of Class A and Class B common stock for Tradeweb Markets Inc.: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands, except share and per share amounts) Numerator: Net income attributable to Tradeweb Markets Inc. $ 54,763 $ 36,812 $ 177,938 $ 111,236 Denominator: Weighted average shares of Class A and Class B common stock outstanding - Basic 202,238,122 187,774,170 201,029,196 177,257,994 Dilutive effect of equity-settled PRSUs 2,146,473 2,584,192 2,000,005 2,371,727 Dilutive effect of options 3,516,893 4,402,391 3,609,906 5,264,106 Dilutive effect of RSUs 295,951 194,942 269,223 132,281 Weighted average shares of Class A and Class B common stock outstanding - Diluted 208,197,439 194,955,695 206,908,330 185,026,108 Earnings per share - Basic $ 0.27 $ 0.20 $ 0.89 $ 0.63 Earnings per share - Diluted $ 0.26 $ 0.19 $ 0.86 $ 0.60 LLC Interests held by the Continuing LLC Owners are redeemable in accordance with the TWM LLC Agreement, at the election of such holders, for shares of Class A or Class B common stock of Tradeweb Markets Inc. The potential dilutive effect of LLC Interests are evaluated under the if-converted method. The potential dilutive effect of PRSUs, shares underlying options and RSUs are evaluated under the treasury stock method. The following table summarizes the PRSUs, shares underlying options, RSUs and weighted-average LLC Interests that were anti-dilutive for the periods indicated. As a result, these shares, which were outstanding, were excluded from the computation of diluted earnings per share for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Anti-dilutive Shares: Equity-settled PRSUs — — — — Options — 178,750 — 264,376 RSUs 465 758 465 506 LLC Interests 30,531,933 39,513,246 30,756,925 48,397,598 Shares of Class C and Class D common stock do not have economic rights in Tradeweb Markets Inc. and, therefore, are not included in the calculation of basic earnings per share and are not participating securities for purposes of the computation of diluted earnings per share.

Regulatory Capital Requirements

Regulatory Capital Requirements	9 Months Ended
	Sep. 30, 2021
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Regulatory Capital Requirements	Regulatory Capital RequirementsTWL, DW, TWD and EA are subject to the Uniform Net Capital Rule 15c3-1 under the Securities Exchange Act of 1934. TEL and TESL are subject to certain financial resource requirements with the FCA in the UK, TWJ is subject to certain financial resource requirements with the FCA in Japan and TWEU is subject to certain finance resource requirements with the AFM in the Netherlands. At September 30, 2021 and December 31, 2020, the regulatory capital requirements and regulatory capital for TWL, DW, TWD, TEL, TWJ, TWEU, TESL and EA are as follows: As of September 30, 2021 TWL DW TWD TEL TWJ TWEU TESL EA (in thousands) Regulatory Capital $ 49,715 $ 56,153 $ 25,973 $ 77,745 $ 8,421 $ 8,857 $ 736 $ 213,232 Regulatory Capital Requirement 2,382 2,504 736 33,505 3,611 3,363 721 159 Excess Regulatory Capital $ 47,333 $ 53,649 $ 25,237 $ 44,240 $ 4,810 $ 5,494 $ 15 $ 213,073 As of December 31, 2020 TWL DW TWD TEL TWJ TWEU (in thousands) Regulatory Capital $ 49,254 $ 58,026 $ 20,577 $ 59,238 $ 11,066 $ 19,102 Regulatory Capital Requirement 2,438 2,147 731 33,742 3,799 2,562 Excess Regulatory Capital $ 46,816 $ 55,879 $ 19,846 $ 25,496 $ 7,267 $ 16,540 As SEFs, TW SEF and DW SEF are required to maintain adequate financial resources and liquid financial assets in accordance with CFTC regulations. The required and maintained financial resources and liquid financial assets at September 30, 2021 and December 31, 2020 are as follows: As of September 30, 2021 As of December 31, 2020 TW SEF DW SEF TW SEF DW SEF (in thousands) Financial Resources $ 43,143 $ 17,345 $ 28,476 $ 15,298 Required Financial Resources 11,000 6,028 13,500 6,223 Excess Financial Resources $ 32,143 $ 11,317 $ 14,976 $ 9,075 Liquid Financial Assets $ 26,123 $ 11,233 $ 15,662 $ 8,610 Required Liquid Financial Assets 2,750 1,507 6,750 3,112 Excess Liquid Financial Assets $ 23,373 $ 9,726 $ 8,912 $ 5,498

Business Segment and Geographic

Business Segment and Geographic Information	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Business Segment and Geographic Information	Business Segment and Geographic Information The Company operates electronic marketplaces for the trading of products across the rates, credit, equities and money markets asset classes and provides related pre-trade and post-trade services. The Company’s operations constitute a single business segment because of the integrated nature of these marketplaces and services. Information regarding revenue by client sector is as follows: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Revenues Institutional $ 163,587 $ 131,860 $ 499,794 $ 407,464 Wholesale 64,838 44,959 185,917 136,967 Retail 16,385 17,453 53,359 59,495 Market Data 20,515 18,598 60,494 55,657 Total revenue 265,325 212,870 799,564 659,583 Operating expenses 179,797 154,349 531,917 467,808 Operating income $ 85,528 $ 58,521 $ 267,647 $ 191,775 The Company operates in the U.S. and internationally, primarily in the Europe and Asia regions. Revenues are attributed to geographic area based on the jurisdiction where the underlying transactions take place. The results by geographic region are not meaningful in understanding the Company’s business. Long-lived assets are attributed to the geographic area based on the location of the particular subsidiary. The following table provides revenue by geographic area: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Revenues U.S. $ 166,268 $ 136,785 $ 497,609 $ 422,114 International 99,057 76,085 301,955 237,469 Total revenue $ 265,325 $ 212,870 $ 799,564 $ 659,583 The following table provides information on the attribution of long-lived assets by geographic area: September 30, December 31, 2021 2020 (in thousands) Long-lived assets U.S. $ 4,183,821 $ 4,091,569 International 15,014 16,544 Total $ 4,198,835 $ 4,108,113

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 27, 2021, the board of directors of Tradeweb Markets Inc. declared a cash dividend of $0.08 per share of Class A common stock and Class B common stock for the fourth quarter of 2021. This dividend will be payable on December 15 , 2021 to stockholders of record as of December 1, 2021. On October 26, 2021, Tradeweb Markets Inc., as the sole manager, approved a distribution by TWM LLC to its equityholders, including Tradeweb Markets Inc., in an aggregate amount of $32.1 million , as adjusted by required state and local tax withholdings that will be determined prior to the record date of December 1, 2021, payable on December 13, 2 021.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The condensed consolidated financial statements include the accounts of the Company and its subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. As discussed in Note 1 – Organization, as a result of the Reorganization Transactions, Tradeweb Markets Inc. consolidates TWM LLC and its subsidiaries and TWM LLC is considered to be the predecessor to Tradeweb Markets Inc. for financial reporting purposes. Tradeweb Markets Inc. had no business transactions or activities and no substantial assets or liabilities prior to the Reorganization Transactions. The condensed consolidated financial statements represent the financial condition and results of operations of the Company and report a non-controlling interest related to the LLC Interests held by the Continuing LLC Owners. These condensed consolidated financial statements are unaudited and should be read in conjunction with the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. The consolidated financial information as of December 31, 2020 has been derived from audited financial statements not included herein. These unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) with respect to interim financial reporting and Form 10-Q. In accordance with such rules and regulations, certain disclosures that are normally included in annual financial statements have been omitted. These unaudited condensed consolidated financial statements reflect all normal and recurring adjustments that are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates and the difference may be material to the condensed consolidated financial statements.
Reclassifications	ReclassificationsCertain reclassifications have been made to prior periods' financial information to conform to the current year presentation. This primarily includes an aggregation of transaction fees and commissions into a single revenue category titled “transaction fees and commissions” for all periods presented in condensed consolidated income statements. These reclassifications had no impact on total consolidated revenue or consolidated net income.
Business Combinations	Business Combinations Business combinations are accounted for under the purchase method of accounting pursuant to Accounting Standards Codification (“ASC”) 805, Business Combinations (“ASC 805”) . The total cost of an acquisition is allocated to the underlying net assets based on their respective estimated fair values. The excess of the purchase price over the estimated fair values of the net assets acquired is recorded as goodwill. The fair value of assets acquired and liabilities assumed is determined based on assumptions that reasonable market participants would use in the principal (or most advantageous) market for the asset or liability. Determining the fair value of certain assets acquired and liabilities assumed is judgmental in nature and often involves the use of significant estimates and assumptions, including assumptions with respect to future cash flows, discount rates, growth rates, customer attrition rates and asset lives.
Pushdown Accounting	Pushdown Accounting In connection with the Refinitiv Transaction, a majority interest of Refinitiv (formerly the Thomson Reuters Financial & Risk Business) was acquired by BCP on October 1, 2018 from TR. The Refinitiv Transaction was accounted for by Refinitiv in accordance with the acquisition method of accounting pursuant to ASC 805 , and pushdown accounting was applied to Refinitiv to record the fair value of the assets and liabilities of Refinitiv as of October 1, 2018, the date of the Refinitiv Transaction. The Company, as a consolidating subsidiary of Refinitiv, also accounted for the Refinitiv Transaction using pushdown accounting which resulted in a new fair value basis of accounting for certain of the Company’s assets and liabilities beginning on October 1, 2018. Under the pushdown accounting applied, the excess of the fair value of the Company above the fair value accounting basis of the net assets and liabilities of the Company as of October 1, 2018 was recorded as goodwill. The fair value of assets acquired and liabilities assumed was determined based on assumptions that reasonable market participants would use in the principal (or most advantageous) market for the asset or liability. The adjusted valuations primarily affected the values of the Company’s long-lived and indefinite-lived intangible assets, including software development costs.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consists of cash and highly liquid investments (such as short-term money market instruments) with original maturities at the time of purchase of three months or less.
Allowance for Credit Losses	Allowance for Credit LossesThe Company continually monitors collections and payments from its clients and maintains an allowance for credit losses. The allowance for credit losses is based on an estimate of the amount of potential credit losses in existing accounts receivable, as determined from a review of aging schedules, past due balances, historical collection experience and other specific account data. Careful analysis of the financial condition of our counterparties is also performed. Once determined uncollectible, aged balances are written off as credit loss expense, which is included in general and administrative expenses on the condensed consolidated statements of income.
Receivable from and Payable to Broker and Dealers and Clearing Organizations	Receivable from and Payable to Brokers and Dealers and Clearing Organizations Receivable from and payable to brokers and dealers and clearing organizations consists of proceeds from transactions executed on the Company’s wholesale platform which failed to settle due to the inability of a transaction party to deliver or receive the transacted security. These securities transactions are generally collateralized by those securities. Until the failed transaction settles, a receivable from (and a matching payable to) brokers and dealers and clearing organizations is recognized for the proceeds from the unsettled transaction.
Deposits with Clearing Organizations	Deposits with Clearing OrganizationsDeposits with clearing organizations are comprised of cash deposits.
Furniture, Equipment, Purchased Software and Leasehold Improvements	Furniture, Equipment, Purchased Software and Leasehold Improvements Furniture, equipment, purchased software and leasehold improvements are carried at cost less accumulated depreciation. Depreciation for furniture, equipment and purchased software is computed on a straight-line basis over the estimated useful lives of the related assets, ranging from three Furniture, equipment, purchased software and leasehold improvements are tested for impairment whenever events or changes in circumstances suggest that an asset’s carrying value may not be fully recoverable in accordance with ASC 360, Property, Plant and Equipment ( “ ASC 360 ” ).
Software Development Costs	Software Development Costs The Company capitalizes costs associated with the development of internal use software at the point at which the conceptual formulation, design and testing of possible software project alternatives have been completed, in accordance with ASC 350, Intangibles – Goodwill and Other ( “ ASC 350 ” ) . The Company capitalizes employee compensation and related benefits and third party consulting costs incurred during the application development stage which directly contribute to such development. Such costs are amortized on a straight-line basis over three years. Software development costs acquired as part of the NFI Acquisition are amortized over one year. Costs capitalized as part of the Refinitiv Transaction pushdown accounting allocation are amortized over nine years. The Company reviews the amounts capitalized for impairment whenever events or changes in circumstances indicate that the carrying amounts of the assets may not be fully recoverable, or that their useful lives are shorter than originally expected. Non-capitalized software costs and routine maintenance costs are expensed as incurred.
Goodwill	Goodwill Goodwill includes the excess of the fair value of the Company above the fair value accounting basis of the net assets and liabilities of the Company as previously applied under pushdown accounting in connection with the Refinitiv Transaction. Goodwill also includes the cost of acquired companies in excess of the fair value of identifiable net assets at the acquisition date, including the NFI Acquisition. Goodwill is not amortized, but in accordance with ASC 350, goodwill is tested for impairment annually on October 1 st and between annual tests, whenever events or changes in circumstances indicate that the carrying amount may not be fully recoverable. Goodwill is tested at the reporting unit level, which is defined as an operating segment or one level below the operating segment. An impairment loss is recognized if the estimated fair value of a reporting unit is less than its net book value. Such loss is calculated as the difference between the estimated fair value of goodwill and its carrying value.
Intangible Assets	Intangible Assets Intangible assets with a finite life are amortized over the estimated lives, ranging from seven
Equity Investments Without Readily Determinable Fair Value	Equity Investments Without Readily Determinable Fair ValuesEquity Investments without a readily determinable fair value are measured at cost, less impairment, plus or minus observable price changes (in orderly transactions) of an identical or similar investment of the same issuer. If the Company determines that the equity investment is impaired on the basis of a qualitative assessment, the Company will recognize an impairment loss equal to the amount by which the investment’s carrying amount exceeds its fair value. Equity investments are included as a component of other assets on the condensed consolidated statements of financial condition.
Leases	Leases The Company has operating leases for corporate offices and data centers with initial lease terms ranging from one The Company adopted Accounting Standards Update (“ASU”) 2016-2, Leases (Topic 842) on January 1, 2019 using the modified retrospective method of adoption and elected to take the optional package of practical expedients, which allowed for no reassessment of: i. whether any expired or existing contracts are or contain leases, ii. the lease classification for any expired or existing leases, and iii. initial direct costs for any existing leases.
Deferred IPO and Follow-On Offering Costs	Deferred IPO and Follow-On Offering Costs Deferred IPO and follow-on offering costs consist of legal, accounting, and other costs directly related to the Company’s efforts to raise capital. In accordance with ASC 505-10-25, Equity
Translation of Foreign Currency and Foreign Currency Forward Contracts	Translation of Foreign Currency and Foreign Currency Forward Contracts Revenues and expenses denominated in foreign currencies are translated at the rate of exchange prevailing at the transaction date. Assets and liabilities denominated in foreign currencies are translated at the rate prevailing at the condensed consolidated statements of financial condition date. Foreign currency re-measurement gains or losses on transactions in nonfunctional currencies are recognized in the condensed consolidated statements of income within general and administrative expenses. The realized and unrealized losses totaled $0.5 million and $45,000 during the three months ended September 30, 2021 and 2020, respectively, and realized and unrealized gains/losses totaled a $2.5 million loss and a $1.3 million gain during the nine months ended September 30, 2021 and 2020, respectively. Gains or losses on translation in the financial statements of a non-U.S. operation, when the functional currency is other than the U.S. dollar, are included as a component of other comprehensive income.
Income Tax	Income Tax The Corporation is subject to U.S. federal, state and local income taxes with respect to its taxable income, including its allocable share of any taxable income of TWM LLC, and is taxed at prevailing corporate tax rates. TWM LLC is a multiple member limited liability company taxed as a partnership and accordingly any taxable income generated by TWM LLC is passed through to and included in the taxable income of its members, including the Corporation. Income taxes also include unincorporated business taxes on income earned or losses incurred for conducting business in certain state and local jurisdictions, income taxes on income earned or losses incurred in foreign jurisdictions on certain operations and federal and state income taxes on income earned or losses incurred, both current and deferred, on subsidiaries that are taxed as corporations for U.S. tax purposes. The Company records deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities. The Company measures deferred taxes using the enacted tax rates and laws that will be in effect when such temporary differences are expected to reverse. The Company evaluates the need for valuation allowances based on the weight of positive and negative evidence. The Company records valuation allowances wherever management believes it is more likely than not that the Company will not be able to realize its deferred tax assets in the future. The Company records uncertain tax positions in accordance with ASC 740, Income Taxes, on the basis of a two-step process whereby (i) the Company determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (ii) for those tax positions that meet the more-likely-than-not recognition threshold, the Company recognizes the amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company recognizes interest and penalties related to income taxes within the provision for income taxes in the condensed consolidated statements of income. Accrued interest and penalties are included within accounts payable, accrued expenses and other liabilities in the condensed consolidated statements of financial condition. The Company has elected to treat taxes due on future U.S. inclusions in taxable income under the global intangible low-taxed income (“GILTI”) provision of the Tax Cuts and Jobs Act as a current period expense when incurred.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for stock-based compensation in accordance with ASC 718, Compensation – Stock Compensation (“ASC 718” ) . ASC 718 focuses primarily on accounting for a transaction in which an entity obtains employee services in exchange for stock-based payments. Under ASC 718, the stock-based payments received by the employees of the Company are accounted for either as equity awards or as liability awards. As an equity award, the Company measures and recognizes the cost of employee services received in exchange for awards of equity instruments based on their estimated fair values measured as of the grant date. These costs are recognized as an expense over the requisite service period, with an offsetting increase to additional paid-in capital. As a liability award, the cost of employee services received in exchange for an award of equity instruments is generally measured based on the grant-date fair value of the award. The fair value of that award is remeasured subsequently at each reporting date through the settlement. Changes in the equity instrument’s fair value during the requisite service period are recognized as compensation cost over that period. For periods following the Reorganization Transactions and the IPO, the fair value of new equity instrument grants is determined based on the price of the Class A common stock on the grant date. Under ASC 718, the grant-date fair value of stock-based awards that do not require future service (i.e., vested awards) are expensed immediately. The grant-date fair value of stock-based awards that require future service, and are graded-vesting awards, are amortized over the relevant service period on a straight-line basis, with each tranche separately measured. The grant-date fair value of stock-based awards that require both future service and the achievement of Company performance-based conditions, are amortized over the relevant service period for the performance-based condition. If in a reporting period it is determined that the achievement of a performance target for a performance-based tranche is not probable, then no expense is recognized for that tranche and any expenses already recognized relating to that tranche in prior reporting periods are reversed in the current reporting period. Prior to the IPO, the Company awarded options to management and other employees (collectively, the “Special Option Award”) under the Amended and Restated Tradeweb Markets Inc. Option Plan (the “Option Plan”). In accounting for the options issued under the Option Plan, compensation expense is measured and recognized for all awards based on their estimated fair values measured as of the grant date. Costs related to these options are recognized as an expense in the condensed consolidated statements of income over the requisite service period, with an offsetting increase to additional paid-in capital. The non-cash stock-based compensation expense associated with the Special Option Award began being expensed in the second quarter of 2019.
Earnings Per Share	Earnings Per Share Basic earnings per share is computed by dividing the net income attributable to the Company’s shares by the weighted-average number of the Company’s shares outstanding during the period. For purposes of computing diluted earnings per share, the weighted-average number of the Company’s shares reflects the dilutive effect that could occur if securities that qualify as participating securities were converted into or exchanged or exercised for TWM LLC’s shares, in the pre-IPO period, and the Class A or Class B common stock, in the post-IPO period, using the treasury stock method, as applicable. Shares of Class C and Class D common stock do not have economic rights in Tradeweb Markets Inc. and, therefore, are not included in the calculation of basic earnings per share.
Fair Value Measurement	Fair Value Measurement The fair value of a financial instrument is the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (the exit price). Instruments that the Company owns (long positions) are marked to bid prices, and instruments that the Company has sold, but not yet purchased (short positions) are marked to offer prices. Fair value measurements do not include transaction costs. The fair value hierarchy under ASC 820, Fair Value Measurement (“ASC 820”) , prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1 measurements) and the lowest priority to unobservable inputs (level 3 measurements). The three levels of the fair value hierarchy under ASC 820 are described below. Basis of Fair Value Measurement A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. • Level 1 : Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2 : Quoted prices in markets that are not considered to be active or financial instruments for which all significant inputs are observable, either directly or indirectly; • Level 3 : Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2021
Business Combination and Asset Acquisition [Abstract]
Schedule of Preliminary Purchase Price Allocated	The preliminary purchase price was allocated as follows: Purchase Price Allocation (in thousands) Cash and cash equivalents $ 33,806 Deposits with clearing organizations 18,147 Accounts receivable 2,779 Equipment 1,498 Software development costs 820 Goodwill 87,981 Intangible assets – customer relationships 99,236 Other assets 897 Accrued compensation (1,289) Deferred revenue (620) Accounts payable, accrued expenses and other liabilities (592) Total 242,663 Less: Cash acquired (33,806) Less: Deposits with clearing organizations acquired (18,147) Less: Preliminary working capital adjustments (710) Purchase price, net of cash and deposits acquired and excluding working capital adjustments $ 190,000

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Schedule of Breakdown of Revenues Between Fixed and Variable Revenues	The breakdown of revenues between fixed and variable revenues for the three and nine months ended September 30, 2021 and 2020 is as follows: Three Months Ended Three Months Ended September 30, 2021 September 30, 2020 (in thousands) (in thousands) Variable Fixed Variable Fixed Revenues Transaction fees and commissions $ 167,437 $ 38,879 $ 123,619 $ 36,556 Subscription fees (1) 445 55,947 400 50,090 Other 181 2,436 117 2,088 Total revenue $ 168,063 $ 97,262 $ 124,136 $ 88,734 (1) Fixed subscription fees for the three months ended September 30, 2021 and 2020 include $15.0 million and $14.3 million, respectively, of Refinitiv market data fees. Nine Months Ended Nine Months Ended September 30, 2021 September 30, 2020 (in thousands) (in thousands) Variable Fixed Variable Fixed Revenues Transaction fees and commissions $ 513,759 $ 115,754 $ 395,927 $ 107,826 Subscription fees (1) 1,367 160,819 1,280 147,892 Other 611 7,254 464 6,194 Total revenue $ 515,737 $ 283,827 $ 397,671 $ 261,912 (1) Fixed subscription fees for the nine months ended September 30, 2021 and 2020 include $45.0 million and $43.5 million respectively, of Refinitiv market data fees.
Schedule of Recognized Revenue and Remaining Deferred Revenue Balance	The revenue recognized and the remaining deferred revenue balance are shown below: Amount (in thousands) Deferred revenue balance - December 31, 2020 $ 23,193 New billings 91,402 Revenue recognized (85,435) Deferred revenue acquired in connection with the NFI Acquisition 620 Deferred revenue balance - September 30, 2021 $ 29,780

Non-Controlling Interests (Tabl

Non-Controlling Interests (Tables)	9 Months Ended
	Sep. 30, 2021
Noncontrolling Interest [Abstract]
Schedule of the Ownership Interest in Noncontrolling Interest	The following table summarizes the ownership interest in Tradeweb Markets LLC: September 30, 2021 September 30, 2020 LLC Ownership LLC Ownership Number of LLC Interests held by Tradeweb Markets Inc. 202,194,257 86.9 % 187,918,774 82.6 % Number of LLC Interests held by non-controlling interests 30,531,933 13.1 % 39,513,246 17.4 % Total LLC Interests outstanding 232,726,190 100.0 % 227,432,020 100.0 %
Schedule of the Impact on Equity Due to Changes in the Company’s Ownership Interest in Noncontrolling Interest	The following table summarizes the impact on Tradeweb Market Inc.'s equity due to changes in the Corporation’s ownership interest in TWM LLC: Net Income Attributable to Tradeweb Markets Inc. and Transfers (to) from the Non-Controlling Interests Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Net income attributable to Tradeweb Markets Inc. $ 54,763 $ 36,812 $ 177,938 $ 111,236 Transfers (to) from non-controlling interests: Increase/(decrease) in Tradeweb Markets Inc.'s additional paid-in capital as a result of ownership changes in TWM LLC (16) (1,478) 85,446 423,581 Net transfers (to) from non-controlling interests (16) (1,478) 85,446 423,581 Change from net income attributable to Tradeweb Markets Inc. and transfers (to) from non-controlling interests $ 54,747 $ 35,334 $ 263,384 $ 534,817

Stockholders' Equity and Stoc_2

Stockholders' Equity and Stock-Based Compensation Plans (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Total Stock-based Compensation Expense	A summary of the Company ’ s total stock-based compensation expense, including expense associated with the CFO Special Equity Awards and the Former CFO Accelerated Stock-based Compensation Expense, is presented below: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Total stock-based compensation expense $ 13,776 $ 9,757 $ 36,943 $ 28,074

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Schedule of Balances From Transactions with Affiliates Included in the Consolidated Statements	As of September 30, 2021 and December 31, 2020, the following balances with such affiliates were included in the condensed consolidated statements of financial condition in the following line items: September 30, December 31, 2021 2020 (in thousands) Accounts receivable $ 175 $ 4,009 Receivable from affiliates 2,806 111 Other assets 2,722 2,722 Accounts payable, accrued expenses and other liabilities 7,637 6,140 Deferred revenue 4,500 4,500 Payable to affiliates 3,390 5,142
Schedule of Affiliates were Included in the Consolidated Statements of Income	The following balances with such affiliates were included in the condensed consolidated statements of income in the following line items: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Revenue: Subscription fees $ 223 $ — $ 998 $ — Refinitiv market data fees (1) 15,002 14,273 45,045 43,466 Other fees 120 — 403 — Expenses: (2) Employee compensation and benefits 293 — 293 — Technology and communications 1,027 740 2,507 2,220 General and administrative 224 — 228 (596) Professional fees 15 — 15 — Occupancy — — — 15 (1) The Company maintains a market data license agreement with Refinitiv. Under the agreement, the Company delivers to Refinitiv certain market data feeds which Refinitiv redistributes to its customers. The Company earns license fees and royalties for these feeds. (2) The Company maintains agreements with Refinitiv to provide the Company with certain real estate, payroll, benefits administration and other administrative services.

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value Measurements	The Company’s financial instruments measured at fair value on the condensed consolidated statements of financial condition as of September 30, 2021 and December 31, 2020 have been categorized based upon the fair value hierarchy as follows: Quoted Prices in active Markets for Identical Assets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total (in thousands) As of September 30, 2021 Assets Cash equivalents – Money market funds $ 410,709 $ — $ — $ 410,709 Receivable from affiliates – Foreign currency forward contracts — 2,642 — 2,642 Total assets measured at fair value $ 410,709 $ 2,642 $ — $ 413,351 Liabilities Payable to affiliates – Foreign currency forward contracts $ — $ — $ — $ — Total liabilities measured at fair value $ — $ — $ — $ — As of December 31, 2020 Assets Cash equivalents – Money market funds $ 541,790 $ — $ — $ 541,790 Total assets measured at fair value $ 541,790 $ — $ — $ 541,790 Liabilities Payable to affiliates – Foreign currency forward contracts $ — $ 3,409 $ — $ 3,409 Total liabilities measured at fair value $ — $ 3,409 $ — $ 3,409
Schedule of Derivative Values	The following table summarizes the aggregate U.S. dollar equivalent notional amount of the Company ’ s foreign currency forward contracts not designated as hedges for accounting purposes: September 30, December 31, 2021 2020 (in thousands) Foreign currency forward contracts – Gross notional amount $ 122,744 $ 122,458 The total realized and unrealized gains (losses) on foreign currency forward contracts recorded within general and administrative expenses in the condensed consolidated statements of income are as follows: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Foreign currency forward contracts not designated in accounting hedge relationship $ 1,262 $ (2,124) $ 6,223 $ (5,087)
Schedule of Financial Instruments Not Measured at Fair Value	The Company’s financial instruments not measured at fair value on the condensed consolidated statements of financial condition as of September 30, 2021 and December 31, 2020 have been categorized based upon the fair value hierarchy as follows: Carrying Value Quoted Prices in Significant Observable Inputs (Level 2) Significant Total Fair Value As of September 30, 2021 (in thousands) Assets Cash and restricted cash $ 412,196 $ 412,196 $ — $ — $ 412,196 Receivable from brokers and dealers and clearing organizations 33,950 — 33,950 — 33,950 Deposits with clearing organizations 24,396 24,396 — — 24,396 Accounts receivable 133,351 — 133,351 — 133,351 Other assets – Memberships in clearing organizations 2,392 — — 2,392 2,392 Total $ 606,285 $ 436,592 $ 167,301 $ 2,392 $ 606,285 Liabilities Payable to brokers and dealers and clearing organizations $ 33,828 $ — $ 33,828 $ — $ 33,828 Total $ 33,828 $ — $ 33,828 $ — $ 33,828 As of December 31, 2020 Assets Cash and restricted cash $ 250,490 $ 250,490 $ — $ — $ 250,490 Receivable from brokers and dealers and clearing organizations 368 — 368 — 368 Deposits with clearing organizations 11,671 11,671 — — 11,671 Accounts receivable 105,286 — 105,286 — 105,286 Other assets – Memberships in clearing organizations 1,586 — — 1,586 1,586 Total $ 369,401 $ 262,161 $ 105,654 $ 1,586 $ 369,401 Liabilities Payable to brokers and dealers and clearing organizations $ 252 $ — $ 252 $ — $ 252 Total $ 252 $ — $ 252 $ — $ 252

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Earnings Per Share	The following table summarizes the calculations of basic and diluted earnings per share of Class A and Class B common stock for Tradeweb Markets Inc.: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands, except share and per share amounts) Numerator: Net income attributable to Tradeweb Markets Inc. $ 54,763 $ 36,812 $ 177,938 $ 111,236 Denominator: Weighted average shares of Class A and Class B common stock outstanding - Basic 202,238,122 187,774,170 201,029,196 177,257,994 Dilutive effect of equity-settled PRSUs 2,146,473 2,584,192 2,000,005 2,371,727 Dilutive effect of options 3,516,893 4,402,391 3,609,906 5,264,106 Dilutive effect of RSUs 295,951 194,942 269,223 132,281 Weighted average shares of Class A and Class B common stock outstanding - Diluted 208,197,439 194,955,695 206,908,330 185,026,108 Earnings per share - Basic $ 0.27 $ 0.20 $ 0.89 $ 0.63 Earnings per share - Diluted $ 0.26 $ 0.19 $ 0.86 $ 0.60
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following table summarizes the PRSUs, shares underlying options, RSUs and weighted-average LLC Interests that were anti-dilutive for the periods indicated. As a result, these shares, which were outstanding, were excluded from the computation of diluted earnings per share for the periods indicated: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 Anti-dilutive Shares: Equity-settled PRSUs — — — — Options — 178,750 — 264,376 RSUs 465 758 465 506 LLC Interests 30,531,933 39,513,246 30,756,925 48,397,598

Regulatory Capital Requiremen_2

Regulatory Capital Requirements (Tables)	9 Months Ended
	Sep. 30, 2021
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Schedule of Regulatory Capital Requirements	At September 30, 2021 and December 31, 2020, the regulatory capital requirements and regulatory capital for TWL, DW, TWD, TEL, TWJ, TWEU, TESL and EA are as follows: As of September 30, 2021 TWL DW TWD TEL TWJ TWEU TESL EA (in thousands) Regulatory Capital $ 49,715 $ 56,153 $ 25,973 $ 77,745 $ 8,421 $ 8,857 $ 736 $ 213,232 Regulatory Capital Requirement 2,382 2,504 736 33,505 3,611 3,363 721 159 Excess Regulatory Capital $ 47,333 $ 53,649 $ 25,237 $ 44,240 $ 4,810 $ 5,494 $ 15 $ 213,073 As of December 31, 2020 TWL DW TWD TEL TWJ TWEU (in thousands) Regulatory Capital $ 49,254 $ 58,026 $ 20,577 $ 59,238 $ 11,066 $ 19,102 Regulatory Capital Requirement 2,438 2,147 731 33,742 3,799 2,562 Excess Regulatory Capital $ 46,816 $ 55,879 $ 19,846 $ 25,496 $ 7,267 $ 16,540
Schedule of Financial Resources and Liquid Financial Resources	The required and maintained financial resources and liquid financial assets at September 30, 2021 and December 31, 2020 are as follows: As of September 30, 2021 As of December 31, 2020 TW SEF DW SEF TW SEF DW SEF (in thousands) Financial Resources $ 43,143 $ 17,345 $ 28,476 $ 15,298 Required Financial Resources 11,000 6,028 13,500 6,223 Excess Financial Resources $ 32,143 $ 11,317 $ 14,976 $ 9,075 Liquid Financial Assets $ 26,123 $ 11,233 $ 15,662 $ 8,610 Required Liquid Financial Assets 2,750 1,507 6,750 3,112 Excess Liquid Financial Assets $ 23,373 $ 9,726 $ 8,912 $ 5,498

Business Segment and Geograph_2

Business Segment and Geographic Information (Tables)	9 Months Ended
	Sep. 30, 2021
Segment Reporting [Abstract]
Schedule of Information Regarding Revenue by Client Sector	Information regarding revenue by client sector is as follows: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Revenues Institutional $ 163,587 $ 131,860 $ 499,794 $ 407,464 Wholesale 64,838 44,959 185,917 136,967 Retail 16,385 17,453 53,359 59,495 Market Data 20,515 18,598 60,494 55,657 Total revenue 265,325 212,870 799,564 659,583 Operating expenses 179,797 154,349 531,917 467,808 Operating income $ 85,528 $ 58,521 $ 267,647 $ 191,775
Schedule of Revenue and Long-Lived Assets by Geographic Location	The following table provides revenue by geographic area: Three Months Ended Nine Months Ended September 30, September 30, 2021 2020 2021 2020 (in thousands) Revenues U.S. $ 166,268 $ 136,785 $ 497,609 $ 422,114 International 99,057 76,085 301,955 237,469 Total revenue $ 265,325 $ 212,870 $ 799,564 $ 659,583 The following table provides information on the attribution of long-lived assets by geographic area: September 30, December 31, 2021 2020 (in thousands) Long-lived assets U.S. $ 4,183,821 $ 4,091,569 International 15,014 16,544 Total $ 4,198,835 $ 4,108,113

Organization (Details)

Organization (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Jun. 25, 2021	Dec. 31, 2020	Sep. 30, 2020
Additional dilutive shares (in shares)	5,959,317	5,879,134
Class C Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001		$ 0.00001
Class D Common Stock
Common stock, par value (in dollars per share)	0.00001	0.00001		0.00001
Class A Common Stock
Common stock, par value (in dollars per share)	0.00001	0.00001		0.00001
Class B Common Stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001		$ 0.00001
NFI Acquisition
All-cash acquisition			$ 190,000
Tradeweb Markets LLC
Ownership interest	86.90%	86.90%		85.10%	82.60%
Ownership percentage, continuing LLC Owners	13.10%	13.10%		14.90%	17.40%
Tradeweb Markets LLC | Refinitiv
Ownership interest	51.50%	51.50%
Tradeweb Markets LLC | Public Investors
Ownership percentage, continuing LLC Owners	45.20%	45.20%
Tradeweb Markets LLC | Class C and Class D Common Stock | Bank Stockholders
Ownership percentage, continuing LLC Owners	3.20%	3.20%
Tradeweb Markets Inc | Refinitiv
Ownership interest	87.90%	87.90%
Tradeweb Markets Inc | Public Investors
Voting power percentage	7.70%	7.70%
Tradeweb Markets Inc | Class C Common Stock | Bank Stockholders
Number of share owned (in shares)	1,654,825	1,654,825
Tradeweb Markets Inc | Class D Common Stock | Refinitiv
Number of share owned (in shares)	22,988,329	22,988,329
Tradeweb Markets Inc | Class D Common Stock | Bank Stockholders
Number of share owned (in shares)	5,767,435	5,767,435
Tradeweb Markets Inc | Class D Common Stock | Other Stockholders
Number of share owned (in shares)	121,344	121,344
Voting power percentage	0.10%	0.10%
Tradeweb Markets Inc | Class A Common Stock | Public Investors
Number of share owned (in shares)	105,261,065	105,261,065
Tradeweb Markets Inc | Class B Common Stock | Refinitiv
Number of share owned (in shares)	96,933,192	96,933,192
Tradeweb Markets Inc | Class C and Class D Common Stock | Bank Stockholders
Ownership percentage, continuing LLC Owners	0.10%	0.10%
Voting power percentage	4.30%	4.30%

Significant Accounting Polici_3

Significant Accounting Policies - Furniture, Equipment, Purchased Software, Leasehold Improvements and Software Development Cost (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Software Development Costs
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life			3 years
Accumulated depreciation and amortization	$ 101.8		$ 101.8		$ 67.4
Amortization of pushdown accounting allocation			9 years
Amortization expense	12.4	$ 9.3	$ 34.4	$ 26.1
Software Development Costs | NFI Acquisition
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets			1 year
Minimum
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets			7 years
Maximum
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life of intangible assets			13 years
Furniture, Equipment, Purchased Software and Leasehold Improvements
Furniture, Equipment, Purchased Software and Leasehold Improvements
Accumulated depreciation and amortization	51.9		$ 51.9		$ 35.4
Depreciation expense	$ 5.7	$ 4.7	$ 16.8	$ 13.3
Furniture, Equipment, Purchased Software and Leasehold Improvements | Minimum
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life			3 years
Furniture, Equipment, Purchased Software and Leasehold Improvements | Maximum
Furniture, Equipment, Purchased Software and Leasehold Improvements
Useful life			7 years

Significant Accounting Polici_4

Significant Accounting Policies - Goodwill (Details)	Oct. 01, 2020USD ($)
Accounting Policies [Abstract]
Impairment of goodwill	$ 0

Significant Accounting Polici_5

Significant Accounting Policies - Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Intangible Assets
Accumulated amortization	$ 300.1		$ 300.1		$ 223.7
Amortization expense	$ 26.8	$ 24.9	$ 76.5	$ 74.6
Minimum
Intangible Assets
Useful life of intangible assets			7 years
Maximum
Intangible Assets
Useful life of intangible assets			13 years

Significant Accounting Polici_6

Significant Accounting Policies - Leases (Details)	Sep. 30, 2021
Minimum
Operating Leased Assets [Line Items]
Initial term of lease	1 year
Maximum
Operating Leased Assets [Line Items]
Initial term of lease	10 years

Significant Accounting Polici_7

Significant Accounting Policies - Deferred IPO Cost Follow-On Offering Costs (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Subsidiary, Sale of Stock [Line Items]
Offering costs incurred	$ 0	$ 0	$ 2,403,000
Initial Public Offering
Subsidiary, Sale of Stock [Line Items]
Deferred costs	15,900,000	15,900,000		$ 15,900,000
Follow On Offering
Subsidiary, Sale of Stock [Line Items]
Deferred costs	$ 5,200,000	$ 5,200,000		$ 5,200,000

Significant Accounting Polici_8

Significant Accounting Policies - Translation of Foreign Currency and Foreign Currency Forward Contracts (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Realized and unrealized gains (losses) on translation adjustments	$ (500)	$ (45)	$ (2,500)	$ 1,300
Foreign currency forward contracts – Gross notional amount | Selling, General and Administrative Expenses
Derivative [Line Items]
Foreign currency forward contracts not designated in accounting hedge relationship	$ 1,262	$ (2,124)	$ 6,223	$ (5,087)

Restricted Cash (Details)

Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Restricted Cash Equivalents [Abstract]
Restricted cash	$ 1,000	$ 1,000

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) - NFI Acquisition - USD ($) $ in Thousands	Jun. 25, 2021	Sep. 30, 2021	Sep. 30, 2021
Business Acquisition [Line Items]
Purchase price, net of cash and deposits acquired and excluding working capital adjustments	$ 190,000
Working capital adjustments	$ 710
Transaction costs		$ 100	$ 4,800
Customer Relationships
Business Acquisition [Line Items]
Intangible assets amortization period	15 years
Useful life of intangible assets			13 years
Software Development Costs
Business Acquisition [Line Items]
Useful life of intangible assets			1 year

Acquisitions - Schedule of Prel

Acquisitions - Schedule of Preliminary Purchase Price (Details) - USD ($) $ in Thousands	Jun. 25, 2021	Sep. 30, 2021	Dec. 31, 2020
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Goodwill		$ 2,782,779	$ 2,694,797
NFI Acquisition
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Cash and cash equivalents	$ 33,806
Deposits with clearing organizations	18,147
Accounts receivable	2,779
Equipment	1,498
Goodwill	87,981
Other assets	897
Accrued compensation	(1,289)
Deferred revenue	(620)
Accounts payable, accrued expenses and other liabilities	(592)
Total	242,663
Less: Cash acquired	(33,806)
Less: Deposits with clearing organizations acquired	(18,147)
Less: Preliminary working capital adjustments	(710)
Purchase price, net of cash and deposits acquired and excluding working capital adjustments	190,000
NFI Acquisition | Software Development Costs
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets	820
NFI Acquisition | Customer Relationships
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net [Abstract]
Intangible assets	$ 99,236

Revenue - Breakdown of Revenues

Revenue - Breakdown of Revenues Between Fixed and Variable (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenues
Total revenue	$ 265,325	$ 212,870	$ 799,564	$ 659,583
Transaction fees and commissions
Revenues
Total revenue	206,316	160,175	629,513	503,753
Other
Revenues
Total revenue	2,617	2,205	7,865	6,658
Refinitiv market data fees
Revenues
Total revenue	15,002	14,273	45,045	43,466
Variable
Revenues
Total revenue	168,063	124,136	515,737	397,671
Variable | Transaction fees and commissions
Revenues
Total revenue	167,437	123,619	513,759	395,927
Variable | Subscription fees
Revenues
Total revenue	445	400	1,367	1,280
Variable | Other
Revenues
Total revenue	181	117	611	464
Fixed
Revenues
Total revenue	97,262	88,734	283,827	261,912
Fixed | Transaction fees and commissions
Revenues
Total revenue	38,879	36,556	115,754	107,826
Fixed | Subscription fees
Revenues
Total revenue	55,947	50,090	160,819	147,892
Fixed | Other
Revenues
Total revenue	$ 2,436	$ 2,088	$ 7,254	$ 6,194

Revenue - Recognized Revenue an

Revenue - Recognized Revenue and Remaining Balances (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Change in Contract with Customer
Deferred revenue balance - beginning of period	$ 23,193
New billings	91,402
Revenue recognized	(85,435)
Deferred revenue acquired in connection with the NFI Acquisition	620
Deferred revenue balance - ending of period	$ 29,780

Revenue - Narrative (Details)

Revenue - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Revenue recognized that was previously deferred	$ 22.7	$ 23.4

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Tax Disclosure [Line Items]
Effective tax rate	23.30%	19.10%	20.00%	20.80%
Remaining percentage of tax benefits			50.00%
Other assets	$ 78,549		$ 78,549		$ 82,460
Refinitiv
Income Tax Disclosure [Line Items]
Other assets	2,700		2,700		2,700
Accounts Payable and Accrued Liabilities
Income Tax Disclosure [Line Items]
Tax liability	$ 2,700		$ 2,700		$ 2,700

Tax Receivable Agreement (Detai

Tax Receivable Agreement (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Tax Receivable Agreement
Percentage of amount of U.S. federal, state and local income or franchise tax savings	50.00%
Tax receivable agreement liability	$ 425,150	$ 404,332

Non-Controlling Interests - Sum

Non-Controlling Interests - Summary of Ownership Interest (Details)	9 Months Ended
	Sep. 30, 2021shares	Sep. 30, 2020shares	Dec. 31, 2020
Class A Common Stock
Non-Controlling Interests
Conversion ratio	1
Class B Common Stock
Non-Controlling Interests
Conversion ratio	1
Tradeweb Markets LLC
Non-Controlling Interests
Number of LLC Interests held by Tradeweb Markets Inc. (in shares)	202,194,257	187,918,774
Number of LLC Interests held by non-controlling interests (in shares)	30,531,933	39,513,246
Total LLC Interests outstanding (in shares)	232,726,190	227,432,020
Number of LLC Interests held by Tradeweb Markets Inc.	86.90%	82.60%	85.10%
Number of LLC Interests held by non-controlling interests	13.10%	17.40%	14.90%
Total LLC Interests outstanding	100.00%	100.00%

Non-Controlling Interests - S_2

Non-Controlling Interests - Summary of Equity Changes Due to Changes in Corporation Ownership (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Noncontrolling Interest [Abstract]
Net income attributable to Tradeweb Markets Inc.	$ 54,763	$ 36,812	$ 177,938	$ 111,236
Decrease in Tradeweb Markets Inc.'s additional paid-in capital as a result of ownership changes in TWM LLC	(16)	(1,478)
Increase in Tradeweb Markets Inc.'s additional paid-in capital as a result of ownership changes in TWM LLC			85,446	423,581
Net transfers (to) from non-controlling interests	(16)	(1,478)	85,446	423,581
Change from net income attributable to Tradeweb Markets Inc. and transfers (to) from non-controlling interests	$ 54,747	$ 35,334	$ 263,384	$ 534,817

Stockholders' Equity and Stoc_3

Stockholders' Equity and Stock-Based Compensation Plans - Narrative (Details) - USD ($)	Sep. 07, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Aug. 30, 2021	Feb. 04, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum performance modifier, percent		0.00%						0.00%
Maximum performance modifier, percent		200.00%						200.00%
Target performance modifier, percent		100.00%						100.00%
Total stock-based compensation expense		$ 13,776,000			$ 9,757,000			$ 36,943,000	$ 28,074,000
Unrecognized compensation expense										$ 1,800,000
Share-based Payment Arrangement, Accelerated Cost		$ 500,000
Average price per share (in dollars per share)		$ 85.10			$ 56.65			$ 68.02	$ 49.82
Common stock, conversion ratio								1
Number of shares withheld (in shares)		36,888			3,171			831,738	1,442,155
Share-based payment arrangement, decrease for tax withholding obligation		$ 3,139,000	$ 7,970,000	$ 45,464,000	$ 180,000	$ 47,672,000	$ 23,991,000	$ 56,600,000	$ 71,800,000
2019 Omnibus Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)		8,841,864						8,841,864
Vesting period								10 years
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period								3 years
Granted (in shares)	44,589	4,542						325,717
Grant date fair value	$ 3,600,000
Weighted-average grant-date fair value (in dollars per share)	$ 80.78	$ 84.99						$ 74.31
Vest per year								33.00%
RSUs | Non-employee director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period								1 year
RSUs | March 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in period (in shares)	19,350
RSUs | March 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in period (in shares)	16,672
RSUs | March 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in period (in shares)	4,948
RSUs | March 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in period (in shares)	3,619
Equity-settled PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period								3 years
Granted (in shares)	4,270							205,655
Weighted-average grant-date fair value (in dollars per share)	$ 80.78							$ 74.16
RSUs and PSRUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense		$ 400,000
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share repurchase program, amount authorized											$ 150,000,000
Common stock repurchased (in shares)		140,169						757,813
Average price per share (in dollars per share)		$ 85.61						$ 84.03
Aggregate value of share repurchase		$ 12,000,000						$ 63,700,000
Stock repurchase program, remaining authorized repurchase amount		$ 86,300,000						$ 86,300,000
April Two Thousand And Twenty Follow On Offering | Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock from equity incentive plans (in shares)						12,835,245
Public offering price (in dollars per share)						$ 50.25
Net proceeds						$ 626,300,000
Stock surrendered (in shares)						596,418
April Two Thousand And Twenty Follow On Offering | LLC Interests
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock surrendered (in shares)						12,238,827
Underwriter | Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued to underwriters (in shares)						1,674,162

Stockholders' Equity and Stoc_4

Stockholders' Equity and Stock-Based Compensation Plans - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Total stock-based compensation expense	$ 13,776	$ 9,757	$ 36,943	$ 28,074

Related Party Transactions - Ba

Related Party Transactions - Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Related Party Transactions [Abstract]
Accounts receivable	$ 175	$ 4,009
Receivable from affiliates	2,806	111
Other assets	2,722	2,722
Accounts payable, accrued expenses and other liabilities	7,637	6,140
Deferred revenue	4,500	4,500
Payable to affiliates	$ 3,390	$ 5,142

Related Party Transactions - Co

Related Party Transactions - Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Expenses
Employee compensation and benefits	$ 98,036	$ 83,967	$ 300,107	$ 263,353
Technology and communications	14,747	12,037	42,248	34,397
General and administrative	9,561	8,657	21,809	24,520
Professional fees	8,897	7,388	28,993	20,908
Occupancy	3,733	3,443	11,104	10,678
Affiliated Entity
Expenses
Employee compensation and benefits	293	0	293	0
Technology and communications	1,027	740	2,507	2,220
General and administrative	224	0	228	(596)
Professional fees	15	0	15	0
Occupancy	0	0	0	15
Subscription fees | Affiliated Entity
Revenue:
Revenue	223	0	998	0
Refinitiv market data fees | Affiliated Entity
Revenue:
Revenue	15,002	14,273	45,045	43,466
Other fees | Affiliated Entity
Revenue:
Revenue	$ 120	$ 0	$ 403	$ 0

Related Party Transactions - Na

Related Party Transactions - Narrative (Details) - USD ($) $ in Millions	1 Months Ended			3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2020	Oct. 31, 2019	Apr. 30, 2019	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Related Party Transactions
Consulting service fee for IPO			$ 1
Consulting service fee for follow on offering	$ 0.5	$ 0.5
Adjustment to additional paid in capital due to consulting service fee					$ 2	$ 2
Affiliated Entity
Related Party Transactions
Related party, payable reversal				$ 1.6

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair Value of Financial Instruments
Receivable from affiliates – Foreign currency forward contracts	$ 2,806	$ 111
Total assets measured at fair value	413,351	541,790
Payable to affiliates – Foreign currency forward contracts	3,390	5,142
Total liabilities measured at fair value	0	3,409
Foreign currency forward contracts
Fair Value of Financial Instruments
Receivable from affiliates – Foreign currency forward contracts	2,642
Payable to affiliates – Foreign currency forward contracts	0	3,409
Cash equivalents – Money market funds
Fair Value of Financial Instruments
Cash equivalents – Money market funds	410,709	541,790
Quoted Prices in active Markets for Identical Assets (Level 1)
Fair Value of Financial Instruments
Total assets measured at fair value	410,709	541,790
Total liabilities measured at fair value	0	0
Quoted Prices in active Markets for Identical Assets (Level 1) | Foreign currency forward contracts
Fair Value of Financial Instruments
Receivable from affiliates – Foreign currency forward contracts	0
Payable to affiliates – Foreign currency forward contracts	0	0
Quoted Prices in active Markets for Identical Assets (Level 1) | Cash equivalents – Money market funds
Fair Value of Financial Instruments
Cash equivalents – Money market funds	410,709	541,790
Significant Observable Inputs (Level 2)
Fair Value of Financial Instruments
Total assets measured at fair value	2,642	0
Total liabilities measured at fair value	0	3,409
Significant Observable Inputs (Level 2) | Foreign currency forward contracts
Fair Value of Financial Instruments
Receivable from affiliates – Foreign currency forward contracts	2,642
Payable to affiliates – Foreign currency forward contracts	0	3,409
Significant Observable Inputs (Level 2) | Cash equivalents – Money market funds
Fair Value of Financial Instruments
Cash equivalents – Money market funds	0	0
Significant Unobservable Inputs (Level 3)
Fair Value of Financial Instruments
Total assets measured at fair value	0	0
Total liabilities measured at fair value	0	0
Significant Unobservable Inputs (Level 3) | Foreign currency forward contracts
Fair Value of Financial Instruments
Receivable from affiliates – Foreign currency forward contracts	0
Payable to affiliates – Foreign currency forward contracts	0	0
Significant Unobservable Inputs (Level 3) | Cash equivalents – Money market funds
Fair Value of Financial Instruments
Cash equivalents – Money market funds	$ 0	$ 0

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Foreign Currency Forward Contracts (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Foreign currency forward contracts – Gross notional amount | Not Designated as Hedging Instrument
Derivative [Line Items]
Gross notional amount	$ 122,744	$ 122,458

Fair Value of Financial Instr_5

Fair Value of Financial Instruments - Unrealized Gains(Losses) on Foreign Currency Forwards (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Foreign currency forward contracts – Gross notional amount | Selling, General and Administrative Expenses
Derivative [Line Items]
Foreign currency forward contracts not designated in accounting hedge relationship	$ 1,262	$ (2,124)	$ 6,223	$ (5,087)

Fair Value of Financial Instr_6

Fair Value of Financial Instruments - Financial Instruments Not Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Fair Value of Financial Instruments
Receivable from brokers and dealers and clearing organizations	$ 33,950	$ 368
Deposits with clearing organizations	24,396	11,671
Accounts receivable	133,351	105,286
Total assets	5,936,500	5,679,850
Payable to brokers and dealers and clearing organizations	33,828	252
Total liabilities	688,171	660,687
Equity investment without readily determinable fair values	21,100	21,100
Fair Value, Nonrecurring
Fair Value of Financial Instruments
Cash and restricted cash	412,196	250,490
Receivable from brokers and dealers and clearing organizations	33,950	368
Deposits with clearing organizations	24,396	11,671
Accounts receivable	133,351	105,286
Other assets – Memberships in clearing organizations	2,392	1,586
Total assets	606,285	369,401
Payable to brokers and dealers and clearing organizations	33,828	252
Total liabilities	33,828	252
Quoted Prices in active Markets for Identical Assets (Level 1) | Fair Value, Nonrecurring
Fair Value of Financial Instruments
Cash and restricted cash	412,196	250,490
Receivable from brokers and dealers and clearing organizations	0	0
Deposits with clearing organizations	24,396	11,671
Accounts receivable	0	0
Other assets – Memberships in clearing organizations	0	0
Total assets	436,592	262,161
Payable to brokers and dealers and clearing organizations	0	0
Total liabilities	0	0
Significant Observable Inputs (Level 2) | Fair Value, Nonrecurring
Fair Value of Financial Instruments
Cash and restricted cash	0	0
Receivable from brokers and dealers and clearing organizations	33,950	368
Deposits with clearing organizations	0	0
Accounts receivable	133,351	105,286
Other assets – Memberships in clearing organizations	0	0
Total assets	167,301	105,654
Payable to brokers and dealers and clearing organizations	33,828	252
Total liabilities	33,828	252
Significant Unobservable Inputs (Level 3) | Fair Value, Nonrecurring
Fair Value of Financial Instruments
Cash and restricted cash	0	0
Receivable from brokers and dealers and clearing organizations	0	0
Deposits with clearing organizations	0	0
Accounts receivable	0	0
Other assets – Memberships in clearing organizations	2,392	1,586
Total assets	2,392	1,586
Payable to brokers and dealers and clearing organizations	0	0
Total liabilities	0	0
Total Fair Value | Fair Value, Nonrecurring
Fair Value of Financial Instruments
Cash and restricted cash	412,196	250,490
Receivable from brokers and dealers and clearing organizations	33,950	368
Deposits with clearing organizations	24,396	11,671
Accounts receivable	133,351	105,286
Other assets – Memberships in clearing organizations	2,392	1,586
Total assets	606,285	369,401
Payable to brokers and dealers and clearing organizations	33,828	252
Total liabilities	$ 33,828	$ 252

Credit Risk (Details)

Credit Risk (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Credit Risk
Total stockholder's equity	$ 4,590,272		$ 4,590,272		$ 4,303,451
Excess net capital	10,000		10,000
Allowance for doubtful accounts	265		265		$ 243
Credit loss recognized (reversed)	110	$ 18	4	$ (11)
Minimum
Credit Risk
Total stockholder's equity	$ 25,000		$ 25,000

Commitments and Contingencies (

Commitments and Contingencies (Details) - Revolving credit facility - USD ($)	Apr. 08, 2019	Sep. 30, 2021	Dec. 31, 2020
Commitments and Contingencies
Revolving credit facility, term	5 years
Maximum borrowing capacity	$ 500,000,000
Commitment fee, percentage	0.25%
Letter of credit issued		$ 500,000	$ 0
Letters of credit outstanding		$ 0	$ 0
Fed Funds Effective Rate
Commitments and Contingencies
Spread	0.50%
One-month LIBOR
Commitments and Contingencies
Spread	1.00%
Base rate
Commitments and Contingencies
Spread	0.75%
LIBOR
Commitments and Contingencies
Spread	1.75%
Floor	0.00%

Earnings Per Share - Basic and

Earnings Per Share - Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net income attributable to Tradeweb Markets Inc.	$ 54,763	$ 36,812	$ 177,938	$ 111,236
Denominator:
Weighted average shares of Class A and Class B common stock outstanding - Basic (in shares)	202,238,122	187,774,170	201,029,196	177,257,994
Dilutive effect (in shares)	5,959,317		5,879,134
Weighted average shares of Class A and Class B common stock outstanding - Diluted (in shares)	208,197,439	194,955,695	206,908,330	185,026,108
Earnings per share - Basic (in dollars per share)	$ 0.27	$ 0.20	$ 0.89	$ 0.63
Earnings per share - Diluted (in dollars per share)	$ 0.26	$ 0.19	$ 0.86	$ 0.60
Equity-settled PRSUs
Denominator:
Dilutive effect (in shares)	2,146,473	2,584,192	2,000,005	2,371,727
Options
Denominator:
Dilutive effect (in shares)	3,516,893	4,402,391	3,609,906	5,264,106
RSUs
Denominator:
Dilutive effect (in shares)	295,951	194,942	269,223	132,281

Earnings Per Share - Antidiluti

Earnings Per Share - Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Equity-settled PRSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	0	0	0	0
Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	0	178,750	0	264,376
RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	465	758	465	506
LLC Interests
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares (in shares)	30,531,933	39,513,246	30,756,925	48,397,598

Regulatory Capital Requiremen_3

Regulatory Capital Requirements (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
TWL
Regulatory Capital Requirements
Regulatory Capital	$ 49,715	$ 49,254
Regulatory Capital Requirement	2,382	2,438
Excess Regulatory Capital	47,333	46,816
DW
Regulatory Capital Requirements
Regulatory Capital	56,153	58,026
Regulatory Capital Requirement	2,504	2,147
Excess Regulatory Capital	53,649	55,879
TWD
Regulatory Capital Requirements
Regulatory Capital	25,973	20,577
Regulatory Capital Requirement	736	731
Excess Regulatory Capital	25,237	19,846
TEL
Regulatory Capital Requirements
Regulatory Capital	77,745	59,238
Regulatory Capital Requirement	33,505	33,742
Excess Regulatory Capital	44,240	25,496
TWJ
Regulatory Capital Requirements
Regulatory Capital	8,421	11,066
Regulatory Capital Requirement	3,611	3,799
Excess Regulatory Capital	4,810	7,267
TWEU
Regulatory Capital Requirements
Regulatory Capital	8,857	19,102
Regulatory Capital Requirement	3,363	2,562
Excess Regulatory Capital	5,494	16,540
TESL
Regulatory Capital Requirements
Regulatory Capital	736
Regulatory Capital Requirement	721
Excess Regulatory Capital	15
TW SEF
Regulatory Capital Requirements
Financial Resources	43,143	28,476
Required Financial Resources	11,000	13,500
Excess Financial Resources	32,143	14,976
Liquid Financial Assets	26,123	15,662
Required Liquid Financial Assets	2,750	6,750
Excess Liquid Financial Assets	23,373	8,912
DW SEF
Regulatory Capital Requirements
Financial Resources	17,345	15,298
Required Financial Resources	6,028	6,223
Excess Financial Resources	11,317	9,075
Liquid Financial Assets	11,233	8,610
Required Liquid Financial Assets	1,507	3,112
Excess Liquid Financial Assets	9,726	$ 5,498
EA
Regulatory Capital Requirements
Regulatory Capital	213,232
Regulatory Capital Requirement	159
Excess Regulatory Capital	$ 213,073

Business Segment and Geograph_3

Business Segment and Geographic Information - Revenue by Client Sector (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Business Segment and Geographic Information
Total revenue	$ 265,325	$ 212,870	$ 799,564	$ 659,583
Operating expenses	179,797	154,349	531,917	467,808
Operating income	85,528	58,521	267,647	191,775
Institutional
Business Segment and Geographic Information
Total revenue	163,587	131,860	499,794	407,464
Wholesale
Business Segment and Geographic Information
Total revenue	64,838	44,959	185,917	136,967
Retail
Business Segment and Geographic Information
Total revenue	16,385	17,453	53,359	59,495
Market Data
Business Segment and Geographic Information
Total revenue	$ 20,515	$ 18,598	$ 60,494	$ 55,657

Business Segment and Geograph_4

Business Segment and Geographic Information - Revenue and Long-lived Assets by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Business Segment and Geographic Information
Revenues	$ 265,325	$ 212,870	$ 799,564	$ 659,583
Long-lived assets	4,198,835		4,198,835		$ 4,108,113
U.S.
Business Segment and Geographic Information
Revenues	166,268	136,785	497,609	422,114
Long-lived assets	4,183,821		4,183,821		4,091,569
International
Business Segment and Geographic Information
Revenues	99,057	$ 76,085	301,955	$ 237,469
Long-lived assets	$ 15,014		$ 15,014		$ 16,544

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 27, 2021	Oct. 26, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020
Subsequent Event [Line Items]
Cash dividend declared (in dollars per share)			$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08
Subsequent Event
Subsequent Event [Line Items]
Capital distributions		$ 32.1
Subsequent Event | Class A Common Stock
Subsequent Event [Line Items]
Cash dividend declared (in dollars per share)	$ 0.08
Subsequent Event | Class B Common Stock
Subsequent Event [Line Items]
Cash dividend declared (in dollars per share)	$ 0.08