Earnings Per Share Attributable to Federated Hermes, Inc. Shareholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator
Net Income Attributable to Federated Hermes, Inc.	$ 95,168	$ 85,822	$ 81,196	$ 64,178	$ 82,107	$ 72,962	$ 62,724	$ 54,546	$ 326,364	$ 272,339	$ 220,297
Less: Total Net Income Available to Participating Unvested Restricted Shareholders									(12,794)	(10,234)	(8,555)
Total Net Income Attributable to Federated Hermes Common Stock - Basic									313,570	262,105	211,742
Less: Total Net Income Available to Unvested Restricted Shareholders of a Nonpublic Consolidated Subsidiary									(2,439)	(872)	(794)
Total Net Income Attributable to Federated Hermes Common Stock - Diluted									$ 311,131	$ 261,233	$ 210,948
Denominator
Basic and Diluted Weighted-Average Federated Hermes Common Stock (in shares)									96,419	97,259	96,949
Earnings Per Share
Net income attributable to Federated Hermes common stock - basic (usd per share)	$ 0.94	$ 0.86	$ 0.81	$ 0.63					$ 3.25	$ 2.69	$ 2.18
Net income attributable to Federated Hermes common stock - diluted (usd per share)	$ 0.93	$ 0.85	$ 0.80	$ 0.63					$ 3.23	$ 2.69	$ 2.18