Loans and Allowance for Credit Losses for Loans - Internal Loan Classification Risk by Loan Portfolio Class by Origination Year (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Total	$ 49,877,248		$ 49,877,248		$ 46,917,200
Gross loan charge-offs
Total	11,327	$ 5,267	43,900	$ 7,862
Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	1,002,521		1,002,521		1,633,478
Year two, fiscal year before current fiscal year	1,277,722		1,277,722		1,115,331
Year three, two years before current fiscal year	997,297		997,297		614,019
Year four, three years before current fiscal year	511,813		511,813		331,400
Year five, four years before current fiscal year	276,221		276,221		258,656
More than five years before current fiscal year	639,161		639,161		458,680
Revolving Loans Amortized Cost Basis	4,580,780		4,580,780		4,393,115
Revolving Loans Converted to Term Loans	1,794		1,794		151
Total	9,287,309		9,287,309		8,804,830
Gross loan charge-offs
Total	3,865	4,540	29,912	6,111
Commercial and industrial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	978,383		978,383		1,600,747
Year two, fiscal year before current fiscal year	1,233,039		1,233,039		1,089,386
Year three, two years before current fiscal year	987,984		987,984		590,406
Year four, three years before current fiscal year	490,159		490,159		322,564
Year five, four years before current fiscal year	267,719		267,719		250,031
More than five years before current fiscal year	565,910		565,910		386,085
Revolving Loans Amortized Cost Basis	4,420,712		4,420,712		4,307,163
Revolving Loans Converted to Term Loans	306		306		144
Total	8,944,212		8,944,212		8,546,526
Commercial and industrial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	16,582		16,582		31,557
Year two, fiscal year before current fiscal year	43,260		43,260		3,367
Year three, two years before current fiscal year	3,257		3,257		19,492
Year four, three years before current fiscal year	19,948		19,948		4,732
Year five, four years before current fiscal year	4,125		4,125		4,369
More than five years before current fiscal year	7,005		7,005		3,558
Revolving Loans Amortized Cost Basis	131,677		131,677		51,021
Revolving Loans Converted to Term Loans	1,488		1,488		7
Total	227,342		227,342		118,103
Commercial and industrial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	6,056		6,056		288
Year two, fiscal year before current fiscal year	754		754		1,734
Year three, two years before current fiscal year	3,288		3,288		4,121
Year four, three years before current fiscal year	1,706		1,706		1,412
Year five, four years before current fiscal year	1,703		1,703		4,256
More than five years before current fiscal year	2,819		2,819		4,879
Revolving Loans Amortized Cost Basis	25,681		25,681		31,698
Revolving Loans Converted to Term Loans	0		0		0
Total	42,007		42,007		48,388
Commercial and industrial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	1,500		1,500		886
Year two, fiscal year before current fiscal year	669		669		20,844
Year three, two years before current fiscal year	2,768		2,768		0
Year four, three years before current fiscal year	0		0		2,692
Year five, four years before current fiscal year	2,674		2,674		0
More than five years before current fiscal year	63,427		63,427		64,158
Revolving Loans Amortized Cost Basis	2,710		2,710		3,233
Revolving Loans Converted to Term Loans	0		0		0
Total	73,748		73,748		91,813
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total	31,608,833		31,608,833		29,432,868
Gross loan charge-offs
Total	6,273	$ 0	11,971	$ 173
Commercial real estate | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	3,103,166		3,103,166		6,923,489
Year two, fiscal year before current fiscal year	6,758,975		6,758,975		5,250,609
Year three, two years before current fiscal year	5,083,854		5,083,854		3,339,684
Year four, three years before current fiscal year	3,211,757		3,211,757		2,752,292
Year five, four years before current fiscal year	2,590,762		2,590,762		1,657,775
More than five years before current fiscal year	6,484,153		6,484,153		5,336,045
Revolving Loans Amortized Cost Basis	557,095		557,095		468,635
Revolving Loans Converted to Term Loans	3,310		3,310		3,504
Total	27,793,072		27,793,072		25,732,033
Commercial real estate | Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	3,006,116		3,006,116		6,815,115
Year two, fiscal year before current fiscal year	6,675,372		6,675,372		5,168,127
Year three, two years before current fiscal year	4,997,069		4,997,069		3,246,885
Year four, three years before current fiscal year	3,073,019		3,073,019		2,672,223
Year five, four years before current fiscal year	2,453,918		2,453,918		1,536,327
More than five years before current fiscal year	6,040,604		6,040,604		5,027,128
Revolving Loans Amortized Cost Basis	542,644		542,644		452,461
Revolving Loans Converted to Term Loans	3,310		3,310		3,504
Total	26,792,052		26,792,052		24,921,770
Commercial real estate | Commercial real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	86,078		86,078		93,286
Year two, fiscal year before current fiscal year	52,939		52,939		48,007
Year three, two years before current fiscal year	51,208		51,208		60,169
Year four, three years before current fiscal year	111,268		111,268		45,447
Year five, four years before current fiscal year	100,524		100,524		62,111
More than five years before current fiscal year	205,971		205,971		125,414
Revolving Loans Amortized Cost Basis	6,621		6,621		8,188
Revolving Loans Converted to Term Loans	0		0		0
Total	614,609		614,609		442,622
Commercial real estate | Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	10,972		10,972		15,088
Year two, fiscal year before current fiscal year	30,664		30,664		34,475
Year three, two years before current fiscal year	35,577		35,577		32,630
Year four, three years before current fiscal year	27,280		27,280		34,622
Year five, four years before current fiscal year	36,320		36,320		59,337
More than five years before current fiscal year	237,578		237,578		183,341
Revolving Loans Amortized Cost Basis	7,830		7,830		7,986
Revolving Loans Converted to Term Loans	0		0		0
Total	386,221		386,221		367,479
Commercial real estate | Commercial real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	0		0		0
Year two, fiscal year before current fiscal year	0		0		0
Year three, two years before current fiscal year	0		0		0
Year four, three years before current fiscal year	190		190		0
Year five, four years before current fiscal year	0		0		0
More than five years before current fiscal year	0		0		162
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term Loans	0		0		0
Total	190		190		162
Commercial real estate | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	399,088		399,088		955,349
Year two, fiscal year before current fiscal year	721,930		721,930		524,647
Year three, two years before current fiscal year	349,830		349,830		61,131
Year four, three years before current fiscal year	32,129		32,129		23,819
Year five, four years before current fiscal year	19,833		19,833		8,676
More than five years before current fiscal year	37,898		37,898		51,941
Revolving Loans Amortized Cost Basis	2,255,053		2,255,053		2,075,272
Revolving Loans Converted to Term Loans	0		0		0
Total	3,815,761		3,815,761		3,700,835
Commercial real estate | Construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	390,550		390,550		942,380
Year two, fiscal year before current fiscal year	702,031		702,031		512,046
Year three, two years before current fiscal year	342,403		342,403		61,131
Year four, three years before current fiscal year	32,129		32,129		22,845
Year five, four years before current fiscal year	18,878		18,878		8,676
More than five years before current fiscal year	20,230		20,230		20,599
Revolving Loans Amortized Cost Basis	2,251,552		2,251,552		2,040,866
Revolving Loans Converted to Term Loans	0		0		0
Total	3,757,773		3,757,773		3,608,543
Commercial real estate | Construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year					0
Year two, fiscal year before current fiscal year					0
Year three, two years before current fiscal year					0
Year four, three years before current fiscal year					0
Year five, four years before current fiscal year					0
More than five years before current fiscal year					0
Revolving Loans Amortized Cost Basis					14,268
Revolving Loans Converted to Term Loans					0
Total					14,268
Commercial real estate | Construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	8,538		8,538		12,969
Year two, fiscal year before current fiscal year	12,969		12,969		12,601
Year three, two years before current fiscal year	7,427		7,427		0
Year four, three years before current fiscal year	0		0		974
Year five, four years before current fiscal year	955		955		0
More than five years before current fiscal year	17,668		17,668		17,599
Revolving Loans Amortized Cost Basis	3,501		3,501		20,138
Revolving Loans Converted to Term Loans	0		0		0
Total	51,058		51,058		64,281
Commercial real estate | Construction | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Year one, current fiscal year	0		0		0
Year two, fiscal year before current fiscal year	6,930		6,930		0
Year three, two years before current fiscal year	0		0		0
Year four, three years before current fiscal year	0		0		0
Year five, four years before current fiscal year	0		0		0
More than five years before current fiscal year	0		0		13,743
Revolving Loans Amortized Cost Basis	0		0		0
Revolving Loans Converted to Term Loans	0		0		0
Total	$ 6,930		6,930		$ 13,743
Commercial and Industrial and Commercial Real Estate
Gross loan charge-offs
2023			0
2022			7,288
2021			24,658
2020			6,479
2019			908
Prior to 2019			2,524
Revolving Loans Amortized Cost Basis			26
Revolving Loans Converted to Term Loans			0
Total			$ 41,883