Loans And Allowance For Credit Losses (Credit Quality Indicators Commercial Loan Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Credit Quality Indicator [Line Items]
Loans charged off	$ 9,048	$ 7,462
Commercial Portfolio Segment [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	935,130		$ 3,096,706
Fiscal Year before Current Fiscal Year	2,975,044		2,060,412
Two Years before Current Fiscal Year	1,886,276		1,219,682
Three Years before Current Fiscal Year	995,329		834,144
Four Years before Current Fiscal Year	773,318		393,625
Prior	894,958		566,436
Revolving Loans Amortized Cost Basis	2,168,374		2,258,796
Total	10,628,429		10,429,801
Loans charged off	292	$ 177
Financing Receivable, Revolving, Writeoff	292
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0
Commercial Portfolio Segment [Member] | Business
Credit Quality Indicator [Line Items]
Current Fiscal Year	542,171		1,465,536
Fiscal Year before Current Fiscal Year	1,276,282		796,948
Two Years before Current Fiscal Year	733,006		472,643
Three Years before Current Fiscal Year	399,577		361,945
Four Years before Current Fiscal Year	335,455		182,044
Prior	386,638		233,171
Revolving Loans Amortized Cost Basis	2,031,338		2,149,438
Total	5,704,467		5,661,725
Loans charged off	292
Financing Receivable, Revolving, Writeoff	292
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0
Commercial Portfolio Segment [Member] | Real estate - construction and land
Credit Quality Indicator [Line Items]
Current Fiscal Year	163,916		538,374
Fiscal Year before Current Fiscal Year	554,793		615,959
Two Years before Current Fiscal Year	549,106		129,632
Three Years before Current Fiscal Year	83,653		27,331
Four Years before Current Fiscal Year	27,431		16,071
Prior	30,973		15,169
Revolving Loans Amortized Cost Basis	27,547		18,559
Total	1,437,419		1,361,095
Loans charged off	0
Financing Receivable, Revolving, Writeoff	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0
Commercial Portfolio Segment [Member] | Real estate - business
Credit Quality Indicator [Line Items]
Current Fiscal Year	229,043		1,092,796
Fiscal Year before Current Fiscal Year	1,143,969		647,505
Two Years before Current Fiscal Year	604,164		617,407
Three Years before Current Fiscal Year	512,099		444,868
Four Years before Current Fiscal Year	410,432		195,510
Prior	477,347		318,096
Revolving Loans Amortized Cost Basis	109,489		90,799
Total	3,486,543		3,406,981
Loans charged off	0
Financing Receivable, Revolving, Writeoff	0
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff	0
Commercial Portfolio Segment [Member] | Pass [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	912,832		3,079,877
Fiscal Year before Current Fiscal Year	2,957,489		1,995,390
Two Years before Current Fiscal Year	1,839,008		1,149,481
Three Years before Current Fiscal Year	953,684		812,816
Four Years before Current Fiscal Year	750,761		345,308
Prior	774,542		492,661
Revolving Loans Amortized Cost Basis	2,145,747		2,255,738
Total	10,334,063		10,131,271
Commercial Portfolio Segment [Member] | Pass [Member] | Business
Credit Quality Indicator [Line Items]
Current Fiscal Year	526,988		1,456,476
Fiscal Year before Current Fiscal Year	1,268,330		782,409
Two Years before Current Fiscal Year	716,669		464,201
Three Years before Current Fiscal Year	374,953		360,844
Four Years before Current Fiscal Year	334,438		180,375
Prior	369,983		219,053
Revolving Loans Amortized Cost Basis	2,008,711		2,146,380
Total	5,600,072		5,609,738
Commercial Portfolio Segment [Member] | Pass [Member] | Real estate - construction and land
Credit Quality Indicator [Line Items]
Current Fiscal Year	156,801		538,022
Fiscal Year before Current Fiscal Year	552,570		596,465
Two Years before Current Fiscal Year	549,106		129,632
Three Years before Current Fiscal Year	83,653		27,331
Four Years before Current Fiscal Year	27,431		1,305
Prior	3,235		2,029
Revolving Loans Amortized Cost Basis	27,547		18,559
Total	1,400,343		1,313,343
Commercial Portfolio Segment [Member] | Pass [Member] | Real estate - business
Credit Quality Indicator [Line Items]
Current Fiscal Year	229,043		1,085,379
Fiscal Year before Current Fiscal Year	1,136,589		616,516
Two Years before Current Fiscal Year	573,233		555,648
Three Years before Current Fiscal Year	495,078		424,641
Four Years before Current Fiscal Year	388,892		163,628
Prior	401,324		271,579
Revolving Loans Amortized Cost Basis	109,489		90,799
Total	3,333,648		3,208,190
Commercial Portfolio Segment [Member] | Special Mention [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	21,171		8,073
Fiscal Year before Current Fiscal Year	6,368		2,548
Two Years before Current Fiscal Year	4,460		8,375
Three Years before Current Fiscal Year	7,935		10,800
Four Years before Current Fiscal Year	10,129		1,043
Prior	2,878		279
Revolving Loans Amortized Cost Basis	676		1,319
Total	53,617		32,437
Commercial Portfolio Segment [Member] | Special Mention [Member] | Business
Credit Quality Indicator [Line Items]
Current Fiscal Year	14,056		3,113
Fiscal Year before Current Fiscal Year	1,606		2,548
Two Years before Current Fiscal Year	4,460		7,757
Three Years before Current Fiscal Year	7,330		1,063
Four Years before Current Fiscal Year	513		67
Prior	1,643		0
Revolving Loans Amortized Cost Basis	676		1,319
Total	30,284		15,867
Commercial Portfolio Segment [Member] | Special Mention [Member] | Real estate - construction and land
Credit Quality Indicator [Line Items]
Current Fiscal Year	7,115		352
Fiscal Year before Current Fiscal Year	207		0
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		0
Prior	0		0
Revolving Loans Amortized Cost Basis	0		0
Total	7,322		352
Commercial Portfolio Segment [Member] | Special Mention [Member] | Real estate - business
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		4,608
Fiscal Year before Current Fiscal Year	4,555		0
Two Years before Current Fiscal Year	0		618
Three Years before Current Fiscal Year	605		9,737
Four Years before Current Fiscal Year	9,616		976
Prior	1,235		279
Revolving Loans Amortized Cost Basis	0		0
Total	16,011		16,218
Commercial Portfolio Segment [Member] | Substandard [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	1,127		8,547
Fiscal Year before Current Fiscal Year	11,015		60,442
Two Years before Current Fiscal Year	40,945		61,826
Three Years before Current Fiscal Year	33,677		10,527
Four Years before Current Fiscal Year	12,427		46,358
Prior	113,146		69,714
Revolving Loans Amortized Cost Basis	21,880		1,739
Total	234,217		259,153
Commercial Portfolio Segment [Member] | Substandard [Member] | Business
Credit Quality Indicator [Line Items]
Current Fiscal Year	1,127		5,752
Fiscal Year before Current Fiscal Year	6,188		10,004
Two Years before Current Fiscal Year	10,059		685
Three Years before Current Fiscal Year	17,261		37
Four Years before Current Fiscal Year	503		810
Prior	10,732		10,342
Revolving Loans Amortized Cost Basis	21,880		1,739
Total	67,750		29,369
Commercial Portfolio Segment [Member] | Substandard [Member] | Real estate - construction and land
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		0
Fiscal Year before Current Fiscal Year	2,016		19,494
Two Years before Current Fiscal Year	0		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		14,766
Prior	27,738		13,140
Revolving Loans Amortized Cost Basis	0		0
Total	29,754		47,400
Commercial Portfolio Segment [Member] | Substandard [Member] | Real estate - business
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		2,795
Fiscal Year before Current Fiscal Year	2,811		30,944
Two Years before Current Fiscal Year	30,886		61,141
Three Years before Current Fiscal Year	16,416		10,490
Four Years before Current Fiscal Year	11,924		30,782
Prior	74,676		46,232
Revolving Loans Amortized Cost Basis	0		0
Total	136,713		182,384
Commercial Portfolio Segment [Member] | Non-Accrual [Member]
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		209
Fiscal Year before Current Fiscal Year	172		2,032
Two Years before Current Fiscal Year	1,863		0
Three Years before Current Fiscal Year	33		1
Four Years before Current Fiscal Year	1		916
Prior	4,392		3,782
Revolving Loans Amortized Cost Basis	71		0
Total	6,532		6,940
Commercial Portfolio Segment [Member] | Non-Accrual [Member] | Business
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		195
Fiscal Year before Current Fiscal Year	158		1,987
Two Years before Current Fiscal Year	1,818		0
Three Years before Current Fiscal Year	33		1
Four Years before Current Fiscal Year	1		792
Prior	4,280		3,776
Revolving Loans Amortized Cost Basis	71		0
Total	6,361		6,751
Commercial Portfolio Segment [Member] | Non-Accrual [Member] | Real estate - business
Credit Quality Indicator [Line Items]
Current Fiscal Year	0		14
Fiscal Year before Current Fiscal Year	14		45
Two Years before Current Fiscal Year	45		0
Three Years before Current Fiscal Year	0		0
Four Years before Current Fiscal Year	0		124
Prior	112		6
Revolving Loans Amortized Cost Basis	0		0
Total	$ 171		$ 189