Consolidated Sponsored Investment Products - Derivatives Offsetting (Details) - Consolidated Sponsored Investment Products [Member] $ in Thousands	Dec. 31, 2015 USD ($)
Offsetting Assets [Line Items]
Assets	$ 4,236
Derivative assets not subject to a master netting agreement	(978)
Total assets subject to a master netting agreement	3,258
Liabilities	1,634
Derivative liabilities not subject to a master netting agreement	(281)
Total liabilities subject to a master netting agreement	1,353
Derivative assets, Derivatives Available for Offset	(1,140)
Derivative assets, Collateral Pledged or Received	(1,784)
Derivative liabilities, Derivatives Available for Offset	(1,140)
Derivative liabilities, Collateral Pledged or Received	(209)
Derivative assets, Net Amount	334
Derivative liabilities, Net Amount	4
Futures [Member]
Offsetting Assets [Line Items]
Assets	77
Liabilities	128
Forward foreign currency exchange [Member]
Offsetting Assets [Line Items]
Assets	388
Liabilities	287
Swaps [Member]
Offsetting Assets [Line Items]
Assets	897
Liabilities	502
Options [Member] | Long [Member]
Offsetting Assets [Line Items]
Assets	2,071
Liabilities	63
Options [Member] | Short [Member]
Offsetting Assets [Line Items]
Assets	0
Liabilities	654
Swaption [Member]
Offsetting Assets [Line Items]
Assets	803
Liabilities	$ 0