Stockholders' Equity - Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Components of basic and diluted earnings per share
Net income attributable to Waddell & Reed Financial, Inc.	$ 30,523	$ 33,054	$ 77,333	$ 99,056
Weighted average shares outstanding - basic and diluted	64,240,000	72,387,000	65,795,000	74,446,000
Earnings per share:
Earnings per share, basic and diluted (in dollars per share)	$ 0.48	$ 0.46	$ 1.18	$ 1.33
Dividends
Dividends declared (in dollars per share)	$ 0.25	$ 0.25	$ 0.75	$ 0.75
Dividends payable to stockholders	$ 15,600		$ 15,600
Common stock repurchases
Shares repurchased in the open market or privately	2,617,108	2,480,019	7,892,913	6,849,238
Shares repurchased from employees to cover income tax withholdings		19	451,245	440,002