Parent Company - Condensed Statements of Financial Condition (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Apr. 21, 2015	Dec. 31, 2014
Assets
Deferred tax asset	$ 125,760	$ 193,859
Other assets	357,352	74,470
Total Assets	7,320,006	3,692,390
Liabilities
Accounts payable and accrued expenses and other liabilities	358,825	69,281
Tax receivable agreement obligations	147,040	231,404
Total Liabilities	6,168,428	3,157,978
Stockholders' / Members' equity
Treasury stock, at cost, 616,923 and 453,066 shares at December 31, 2017 and 2016, respectively	(11,041)	(8,358)	$ (3,819)
Additional paid-in capital	900,746	155,536
(Accumulated deficit) Retained earnings	(62,129)	(1,254)
Accumulated other comprehensive (loss) income	2,991	(252)
Total stockholders' equity	830,569	145,673
Total liabilities and equity	$ 7,320,006	$ 3,692,390
Treasury stock shares	616,923	453,066
VFH
Assets
Cash	$ 60,193	$ 17,149	$ 187		$ 25,939
Deferred tax asset	124,631	192,961
Receivable from subsidiaries	10,731	1,892
Investment in subsidiary	1,549,162	165,204
Total Assets	1,744,717	377,206
Liabilities
Payable to affiliates	767,101	129
Accounts payable and accrued expenses and other liabilities	7
Tax receivable agreement obligations	147,040	231,404
Total Liabilities	914,148	231,533
Stockholders' / Members' equity
Treasury stock, at cost, 616,923 and 453,066 shares at December 31, 2017 and 2016, respectively	(11,041)	(8,358)
Additional paid-in capital	900,746	155,536
(Accumulated deficit) Retained earnings	(62,129)	(1,254)
Accumulated other comprehensive (loss) income	2,991	(252)
Total stockholders' equity	830,569	145,673
Total liabilities and equity	$ 1,744,717	$ 377,206
Treasury stock shares	616,923	453,066
Class A-1 | VFH
Stockholders' / Members' equity
Common stock, authorized	0	0
Common stock shares issued	0	0
Common stock, outstanding	0	0
Class A-2 | VFH
Stockholders' / Members' equity
Common stock, authorized	0	0
Common stock shares issued	0	0
Common stock, outstanding	0	0
Class A
Stockholders' / Members' equity
Common stock	$ 1
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001		$ 0.00001
Common stock, authorized	1,000,000,000	1,000,000,000
Common stock shares issued	90,415,532	40,436,580
Common stock, outstanding	89,798,609	39,983,514
Class A | VFH
Stockholders' / Members' equity
Common stock	$ 1
Common stock, par value (in dollars per share)	$ 0.00001
Common stock, authorized	1,000,000,000	1,000,000,000
Common stock shares issued	90,415,532	40,436,580
Common stock, outstanding	89,798,609	39,983,514
Class B
Stockholders' / Members' equity
Common stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, authorized	175,000,000	175,000,000
Common stock shares issued	0	0
Common stock, outstanding	0	0
Class B | VFH
Stockholders' / Members' equity
Common stock
Common stock, par value (in dollars per share)	$ 0.00001
Common stock, authorized	175,000,000	175,000,000
Common stock shares issued	0	0
Common stock, outstanding	0	0
Class C
Stockholders' / Members' equity
Common stock
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, authorized	90,000,000	90,000,000
Common stock shares issued	17,880,239	19,810,707
Common stock, outstanding	17,880,239	19,810,707
Class C | VFH
Stockholders' / Members' equity
Common stock
Common stock, par value (in dollars per share)	$ 0.00001
Common stock, authorized	90,000,000	90,000,000
Common stock shares issued	17,880,239	19,810,707
Common stock, outstanding	17,880,239	19,810,707
Class D
Stockholders' / Members' equity
Common stock	$ 1	$ 1
Common stock, par value (in dollars per share)	$ 0.00001	$ 0.00001
Common stock, authorized	175,000,000	175,000,000
Common stock shares issued	79,610,490	79,610,490
Common stock, outstanding	79,610,490	79,610,490
Class D | VFH
Stockholders' / Members' equity
Common stock	$ 1	$ 1
Common stock, par value (in dollars per share)	$ 0.00001
Common stock, authorized	175,000,000	175,000,000
Common stock shares issued	79,610,490	79,610,490
Common stock, outstanding	79,610,490	79,610,490