Fair Value Measurements (Summary Of Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fair Value Assets Measured on Recurring Basis [Roll Forward]
Beginning balance		$ 155,534	$ 103,863	$ 149,961	$ 105,077
Total gains or losses (realized /unrealized), included in earnings		15,502	16,246	22,457	23,604
Total gains or losses (realized/unrealized), included in other comprehensive income	[1]	(87)	18	(170)	17
Discount accretion		1	3	2	6
Purchase of private equity securities		822	5,656	1,122	5,656
Sale/pay down of private equity investments		(8,095)	(356)	(9,840)	(8,832)
Capitalized interest/dividends		0	23	0	23
Purchase Of Risk Participation Agreement		314	445	459	445
Sale Of Risk Participation Agreement		(250)	(32)	(250)	(130)
Ending balance		163,741	125,866	163,741	125,866
Total gains or losses for the six months included in earnings attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		15,781	18,100	23,169	26,660
*Total gains or losses for the six months included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		(87)	18	(170)	17
State and Municipal Obligations
Fair Value Assets Measured on Recurring Basis [Roll Forward]
Beginning balance		1,902	7,970	1,984	7,968
Total gains or losses (realized /unrealized), included in earnings		0	0	0	0
Total gains or losses (realized/unrealized), included in other comprehensive income	[1]	(87)	18	(170)	17
Discount accretion		1	3	2	6
Purchase of private equity securities		0	0	0	0
Sale/pay down of private equity investments		0	0	0	0
Capitalized interest/dividends		0	0	0	0
Purchase Of Risk Participation Agreement		0	0	0	0
Sale Of Risk Participation Agreement		0	0	0	0
Ending balance		1,816	7,991	1,816	7,991
Total gains or losses for the six months included in earnings attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		0	0	0	0
*Total gains or losses for the six months included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		(87)	18	(170)	17
Private Equity Investments
Fair Value Assets Measured on Recurring Basis [Roll Forward]
Beginning balance		153,411	94,257	147,406	94,368
Total gains or losses (realized /unrealized), included in earnings		15,633	16,666	23,083	25,031
Total gains or losses (realized/unrealized), included in other comprehensive income	[1]	0	0	0	0
Discount accretion		0	0	0	0
Purchase of private equity securities		822	5,656	1,122	5,656
Sale/pay down of private equity investments		(8,095)	(356)	(9,840)	(8,832)
Capitalized interest/dividends		0	23	0	23
Purchase Of Risk Participation Agreement		0	0	0	0
Sale Of Risk Participation Agreement		0	0	0	0
Ending balance		161,771	116,246	161,771	116,246
Total gains or losses for the six months included in earnings attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		15,633	16,666	23,033	25,031
*Total gains or losses for the six months included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		0	0	0	0
Derivatives
Fair Value Assets Measured on Recurring Basis [Roll Forward]
Beginning balance		221	1,636	571	2,741
Total gains or losses (realized /unrealized), included in earnings		(131)	(420)	(626)	(1,427)
Total gains or losses (realized/unrealized), included in other comprehensive income	[1]	0	0	0	0
Discount accretion		0	0	0	0
Purchase of private equity securities		0	0	0	0
Sale/pay down of private equity investments		0	0	0	0
Capitalized interest/dividends		0	0	0	0
Purchase Of Risk Participation Agreement		314	445	459	445
Sale Of Risk Participation Agreement		(250)	(32)	(250)	(130)
Ending balance		154	1,629	154	1,629
Total gains or losses for the six months included in earnings attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		148	1,434	136	1,629
*Total gains or losses for the six months included in other comprehensive income attributable to the change in unrealized gains or losses relating to assets still held at June 30, 2022		$ 0	$ 0	$ 0	$ 0

[1] * Included in "net unrealized gains (losses) on available for sale debt securities" in the consolidated statements of comprehensive income.