Consolidation - Consolidated Federated Fund VIEs (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Federated's Net Interest in Federated Fund VIEs	$ 10.1	$ 12.7
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure
Variable Interest Entity [Line Items]
Less: Liabilities	0.3	0.4
Less: Redeemable Noncontrolling Interest in Subsidiaries	11.2	27.7
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure | Cash and Cash Equivalents
Variable Interest Entity [Line Items]
Consolidated VIE assets	0.0	0.1
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure | Investments—Consolidated Investment Companies
Variable Interest Entity [Line Items]
Consolidated VIE assets	21.2	39.7
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure | Receivables
Variable Interest Entity [Line Items]
Consolidated VIE assets	$ 0.4	$ 1.0