Goodwill And Intangible Assets (Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands		Jun. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		$ 187,622	$ 175,716
Accumulated Amortization		73,930	68,207
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		146,875	146,986
Accumulated Amortization		60,271	55,809
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		24,713	24,713
Accumulated Amortization		10,991	10,228
Investment Banking Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		1,431	1,419
Accumulated Amortization		1,137	968
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		2,603	2,598
Accumulated Amortization		1,331	$ 1,202
Estimated Ziegler Intangibles [Members]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	[1]	12,000
Accumulated Amortization	[1]	$ 200

[1] See discussion regarding the allocation of the estimated goodwill and intangibles recorded for the Ziegler acquisition.