Earnings Per Share Attributable to Federated Investors, Inc. Shareholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator
Net Income Attributable to Federated Investors, Inc.	$ 62,724	$ 38,822	$ 117,270	$ 99,153
Less: Total Net Income Available to Participating Unvested Restricted Shareholders	(2,404)	(1,529)	(4,542)	(3,907)
Total Net Income Attributable to Federated Common Stock - Basic	60,320	37,293	112,728	95,246
Less: Total Net Income Available to Unvested Restricted Shareholders of a Nonpublic Consolidated Subsidiary	(166)	0	(199)	0
Total Net Income Attributable to Federated Common Stock - Diluted	$ 60,154	$ 37,293	$ 112,529	$ 95,246
Denominator
Basic Weighted-Average Federated Common Stock (in shares)	97,330	97,193	97,163	97,191
Dilutive Potential Shares from Stock Options (in shares)	0	1	0	1
Diluted Weighted-Average Federated Common Stock (in shares)	97,330	97,194	97,163	97,192
Earnings Per Share
Net Income Attributable to Federated Common Stock – Basic and Diluted (usd per share)	$ 0.62	$ 0.38	$ 1.16	$ 0.98

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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