Segment Information (Schedule Of Operating Results By Segment) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) segments	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of Operating Segments | segments			1
Net interest income	$ 81,602	$ 83,840	$ 246,187	$ 241,309
(Recovery of) provision for credit losses	1,972	13,836	(6,923)	31,213
Other income and security gains	32,411	36,558	97,738	90,008
Total other expense	68,489	69,859	207,754	200,934
Income (loss) before income taxes	43,552	36,703	143,094	99,170
Income Tax Expense (Benefit)	8,118	5,857	25,697	16,447
Net Income	35,434	30,846	117,397	82,723
Assets	10,034,018	9,240,006	10,034,018	9,240,006	$ 9,279,021
PNB [Member]
Segment Reporting Information [Line Items]
Net interest income	82,835	83,795	247,596	238,900
(Recovery of) provision for credit losses	4,276	13,839	(3,670)	32,256
Other income and security gains	31,332	35,430	95,258	89,920
Total other expense	64,663	65,590	195,361	187,661
Income (loss) before income taxes	45,228	39,796	151,163	108,903
Income Tax Expense (Benefit)	8,777	6,908	28,694	19,357
Net Income	36,451	32,888	122,469	89,546
Assets	10,012,868	9,195,911	10,012,868	9,195,911
All Other [Member]
Segment Reporting Information [Line Items]
Net interest income	(1,233)	45	(1,409)	2,409
(Recovery of) provision for credit losses	(2,304)	(3)	(3,253)	(1,043)
Other income and security gains	1,079	1,128	2,480	88
Total other expense	3,826	4,269	12,393	13,273
Income (loss) before income taxes	(1,676)	(3,093)	(8,069)	(9,733)
Income Tax Expense (Benefit)	(659)	(1,051)	(2,997)	(2,910)
Net Income	(1,017)	(2,042)	(5,072)	(6,823)
Assets	$ 21,150	$ 44,095	$ 21,150	$ 44,095