Investments In Securities (Schedule of Other Investments) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Other Equity Investments
Beginning of period	$ 6,589	$ 5,439
Amounts Impaired	0	0
Observable Changes	0	0
Purchases and Additional Commitments Paid	613	1,486
Sales, Returns of Capital and Other Reductions	1,018	336
End of period	$ 6,184	$ 6,589