Stockholders' Equity - Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	9 Months Ended
Jul. 24, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Components of basic and diluted earnings per share
Net income attributable to Waddell & Reed Financial, Inc.		$ 46,305	$ 53,582	$ 137,120	$ 111,515
Weighted average shares outstanding - basic and diluted		79,595,000	83,476,000	81,372,000	83,719,000
Earnings per share:
Earnings per share, basic and diluted (in dollars per share)		$ 0.58	$ 0.64	$ 1.69	$ 1.33
Dividends
Dividends accrued, per share (in dollars per share)	$ 0.25			$ 0.75
Dividends to be paid		$ 19,700		$ 19,700
Common stock repurchases
Shares repurchased in the open market or privately		1,424,612	190,056	4,519,546	904,410
Shares repurchased from employees to cover income tax withholdings		225	56	630,159	239,410

Aggregate dividends declared during the period for each share of common stock outstanding.

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