Fair Value Measurements (Fair Value Of Certain Financial Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity available-for-sale securities	$ 11,250	$ 9,581
Fixed income available-for-sale securities	76,733	74,452
Fixed income securities owned	21,526	21,339
Investment funds sponsored by LSV	6,034	4,858
Assets, fair value	115,543	110,230
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity available-for-sale securities	11,250	9,581
Fixed income available-for-sale securities	0	0
Fixed income securities owned	0	0
Assets, fair value	11,250	9,581
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity available-for-sale securities	0	0
Fixed income available-for-sale securities	76,733	74,452
Fixed income securities owned	21,526	21,339
Assets, fair value	$ 98,259	$ 95,791