Fair Value Of Financial Instruments (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Commitments to fund additional investments in nonmarketable equity securities	$ 11,500,000	$ 12,400,000
Fair Value Level Into Level 3 Transfers Amount	2,700,000
Transfers of financial assets from level 2 to level 1	15,000,000
Fair Value Level One To Level Two Transfers Amount	11,500,000
Transfers, Out of Level 3, Assets	6,262,000
General and limited partnership interests in investment partnerships	42,100,000	56,000,000
Direct investments in private equity companies held by private equity funds	21,200,000	8,200,000
Stated interest rate	5.375%
Level 3 [Member] | KBW [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned and investments acquired as part of the merger	$ 54,100,000