Fair Value Measurements (Summary Of Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 82,629,000	$ 70,705,000	$ 73,271,000	$ 67,760,000
Total gains or losses (realized /unrealized), included in earnings	3,955,000	17,000	8,425,000	(2,297,000)
Total gains or losses (realized /unrealized), included in other comprehensive income	(379,000)	319,000	(246,000)	710,000
Investment Securities Called	(1,715,000)	(600,000)	(1,715,000)	(600,000)
Discount accretion	9,000	23,000	18,000	33,000
Purchase of private equity securities	364,000	2,259,000	5,243,000	7,084,000
Sales And Repayments Of Private Equity Securities	(166,000)	(1,550,000)	(186,000)	(1,550,000)
Capitalized interest/dividends	0	0	35,000	33,000
Sale Of Risk Participation Agreement	0	0	(148,000)	0
Ending balance	84,697,000	71,173,000	84,697,000	71,173,000
Total gains or losses included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end	4,538,000	920,000	9,006,000	(1,773,000)
State And Municipal Obligations [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	17,158,000	17,083,000	17,016,000	16,682,000
Total gains or losses (realized /unrealized), included in earnings	0	0	0	0
Total gains or losses (realized /unrealized), included in other comprehensive income	(379,000)	319,000	(246,000)	710,000
Investment Securities Called	(1,715,000)	(600,000)	(1,715,000)	(600,000)
Discount accretion	9,000	23,000	18,000	33,000
Purchase of private equity securities	0	0	0	0
Sales And Repayments Of Private Equity Securities	0	0	0	0
Capitalized interest/dividends	0	0	0	0
Sale Of Risk Participation Agreement	0	0	0	0
Ending balance	15,073,000	16,825,000	15,073,000	16,825,000
Total gains or losses included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end	0	0	0	0
Private Equity Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	64,951,000	52,800,000	55,752,000	50,820,000
Total gains or losses (realized /unrealized), included in earnings	3,791,000	48,000	8,096,000	(2,830,000)
Total gains or losses (realized /unrealized), included in other comprehensive income	0	0	0	0
Investment Securities Called	0	0	0	0
Discount accretion	0	0	0	0
Purchase of private equity securities	364,000	2,259,000	5,243,000	7,084,000
Sales And Repayments Of Private Equity Securities	(166,000)	(1,550,000)	(186,000)	(1,550,000)
Capitalized interest/dividends	0	0	35,000	33,000
Sale Of Risk Participation Agreement	0	0	0	0
Ending balance	68,940,000	53,557,000	68,940,000	53,557,000
Total gains or losses included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end	3,791,000	48,000	8,096,000	(2,655,000)
Derivative Level Three Unobservable Inputs [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	520,000	822,000	503,000	258,000
Total gains or losses (realized /unrealized), included in earnings	164,000	(31,000)	329,000	533,000
Total gains or losses (realized /unrealized), included in other comprehensive income	0	0	0	0
Investment Securities Called	0	0	0	0
Discount accretion	0	0	0	0
Purchase of private equity securities	0	0	0	0
Sales And Repayments Of Private Equity Securities	0	0	0	0
Capitalized interest/dividends	0	0	0	0
Sale Of Risk Participation Agreement	0	0	(148,000)	0
Ending balance	684,000	791,000	684,000	791,000
Total gains or losses included in earnings attributable to the change in unrealized gains or losses relating to assets still held at period end	$ 747,000	$ 872,000	$ 910,000	$ 882,000