Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2017
Cash flows from operating activities
Financial Designation, Predecessor and Successor [Fixed List]	Successor	Predecessor	Successor	Predecessor
Net income	$ 29,307	$ 130,160	$ 173,024	$ 83,648
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	33,020	48,808	139,330	68,615
Contingent consideration		26,830		58,520
Vesting of P-1 (C) Shares		(5,728)
Stock-based compensation expense			49,824
Deferred taxes	968	2,602	15,024	(950)
Tax receivable agreement liability adjustment			(33,134)
(Increase) decrease in operating assets:
Receivable from/Payable to brokers and dealers and clearing organizations, net	1,265	(4,640)	3,188	(2)
Deposits with clearing organizations	(2,248)	726	1,789	606
Accounts receivable	8,085	(28,434)	(4,283)	11,196
Receivable from/Payable to affiliates, net	(1,102)	(1,850)	(2,461)	(135)
Other assets	(4,695)	(6,371)	(5,648)	4,719
Increase (decrease) in operating liabilities:
Accrued compensation	38,368	(7,568)	(1,783)	12,364
Deferred revenue	(396)	(1,396)	(3,905)	(12,555)
Accounts payable, accrued expenses and other liabilities	639	8,793	(3,550)	(3,826)
Employee equity compensation payable	9,345	2,896	(16,412)	2,380
Net cash provided by operating activities	112,556	164,828	311,003	224,580
Cash flows from investing activities
Purchase of furniture, equipment, software and leasehold improvements	(9,090)	(6,327)	(15,781)	(13,461)
Capitalized software development costs	(7,156)	(19,523)	(28,681)	(27,157)
Business acquisitions				66
Purchase of investments				(5,000)
Net cash used in investing activities	(16,246)	(25,850)	(44,462)	(45,552)
Cash flows from financing activities
Mezzanine capital contributions				82
Mezzanine capital distributions				(1,543)
Pre-IPO capital distributions	(36,000)	(139,350)	(120,000)	(152,000)
Proceeds from issuance of Class A common stock in the IPO, net of underwriting discounts			1,161,270
Purchase of LLC Interests and Class A common stock in connection with the IPO			(1,161,270)
Proceeds from issuance of Class A common stock in the follow-on offering			809,954
Purchase of LLC Interests in connection with the follow-on offering			(809,954)
Offering costs from IPO and follow-on offering			(14,943)
Dividends			(35,936)
Capital distributions to non-controlling interests			(38,346)
Payroll taxes paid for stock-based compensation exercises			(8,917)
Net cash used in financing activities	(36,000)	(139,350)	(218,142)	(153,461)
Effect of exchange rate changes on cash and cash equivalents	(389)	(2,043)	2,008	3,157
Net increase (decrease) in cash and cash equivalents	59,921	(2,415)	50,407	28,724
Cash and cash equivalents and restricted cash
Beginning of period	351,383	353,798	411,304	325,074
End of period	411,304	351,383	461,711	353,798
Supplemental disclosure of cash flow information
Interest paid				455
Income taxes paid	2,659	5,500	43,842	6,312
Non-cash financing activities - Items arising from the reorganization transactions, IPO, follow-on offering and other LLC Interest ownership changes:
Deferred tax asset	968	2,602	15,024	(950)
Vesting of contingent consideration		150,495
Conversion of convertible term note payable to Thomson Reuters to Class A Shares				$ 29,285
Conversion of certain cash-settled PRSUs to equity-settled PRSUs	$ 19,072
Refinitiv Transaction
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred taxes			269,569
Non-cash financing activities - Items arising from the reorganization transactions, IPO, follow-on offering and other LLC Interest ownership changes:
Establishment of liabilities under tax receivable agreement			273,951
Deferred tax asset			$ 269,569
Vesting of contingent consideration		$ 150,495