Investments Gain on Securities, Net of Investment Income (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Gain (Loss) on Investments [Line Items]
Other-than-temporary impairment on available-for-sale securities		$ 0	$ 1,600	$ 1,300
Gain (loss) on securities, net	[1]	8,072	2,108	(5,264)
Trading Securities [Member]
Gain (Loss) on Investments [Line Items]
Net unrealized gains (losses) on trading securities		118	4,971	(1,359)
Realized gains	[2]	2,404	1,663	910
Realized losses	[2]	(917)	(2,252)	(2,760)
Derivative [Member]
Gain (Loss) on Investments [Line Items]
Net unrealized gains (losses) on derivatives	[3]	771	(348)	119
Realized gains	[2],[3]	1,648	1,032	301
Realized losses	[2],[3]	(419)	(1,609)	(1,630)
Available-for-sale Securities [Member]
Gain (Loss) on Investments [Line Items]
Realized gains	[2]	5,348	298	1,503
Realized losses	[2],[4]	(881)	(1,647)	(2,348)
Consolidated Products [Member]
Gain (Loss) on Investments [Line Items]
Gain (loss) on securities, net		$ 3,000	$ 2,900	$ (4,000)

[1] Amounts related to consolidated entities, primarily Federated Funds, totaled $3.0 million, $2.9 million and $(4.0) million for the years ended December 31, 2017, 2016 and 2015, respectively.

[2] Realized gains and losses are computed on a specific-identification basis.

[3] Amounts related to the settlement of economic derivatives held by certain consolidated Federated Funds.

[4] The losses for the years ended December 31, 2016 and 2015 include $1.6 million and $1.3 million, respectively, for impairments of certain available-for-sale securities.