Accumulated Other Comprehensive Income (Loss) Attributable to Federated Hermes, Inc. Shareholders (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 857,121	$ 761,215	$ 595,784
Other Comprehensive Income (Loss) Before Reclassifications and Tax	14,368	(13,607)	3,321
Tax Impact			(1,067)
Reclassification Adjustment, before tax		(322)	(3,854)
Tax Impact		102	1,333
Other Comprehensive Income (Loss), net of tax	21,275	(19,836)	(267)
Ending balance	1,041,280	857,121	761,215
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(14,617)	(790)	(523)
Other Comprehensive Income (Loss), net of tax	14,368	(13,827)	(267)
Ending balance	(249)	(14,617)	(790)
Unrealized Gain (Loss) on Equity Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	0	29	908
Other Comprehensive Income (Loss) Before Reclassifications and Tax	0	0	2,546
Tax Impact			(904)
Reclassification Adjustment, before tax		(80)	(3,854)
Tax Impact		51	1,333
Other Comprehensive Income (Loss), net of tax	0	(29)	(879)
Ending balance	0	0	29
Foreign Currency Translation (Loss) Gain
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(14,617)	(819)	(1,431)
Other Comprehensive Income (Loss) Before Reclassifications and Tax	14,368	(13,607)	775
Tax Impact			(163)
Reclassification Adjustment, before tax		(242)	0
Tax Impact		51	0
Other Comprehensive Income (Loss), net of tax	14,368	(13,798)	612
Ending balance	$ (249)	$ (14,617)	$ (819)

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