v3.26.1
Segment Reporting - Net Income (GAAP) (Details)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
segment
Jun. 30, 2025
USD ($)
Segment Reporting        
Number of reportable operating segments | segment     1  
Net Income (GAAP)        
Interest income $ 838,259 $ 840,504 $ 1,655,088 $ 1,649,070
Interest expense 262,310 262,556 517,534 526,575
Net interest income (a) 575,949 577,948 1,137,554 1,122,495
Provision for credit losses 15,919 7,505 26,727 108,067
Net interest income after provision for credit losses 560,030 570,443 1,110,827 1,014,428
Total noninterest income        
Securities (losses) gain, net       (228,811)
Gain on sale-leaseback, net of transaction costs       229,279
Total noninterest income 96,726 86,817 196,824 172,905
Total noninterest expense        
Salaries and employee benefits 205,377 200,162 411,030 395,973
Occupancy expense 43,878 41,507 86,180 77,000
Information services expense 29,136 30,155 58,840 61,517
Professional fees 5,090 4,658 10,329 9,367
Amortization of intangibles 21,041 24,048 42,345 47,879
FDIC assessment and other regulatory charges 10,753 11,469 21,010 22,727
Merger and branch consolidation related expense   24,379   92,385
Total noninterest expense 357,749 375,061 717,273 783,887
Income before income tax provision 299,007 282,199 590,378 403,446
Income tax provision 68,985 66,975 134,536 99,142
Net income (GAAP) 230,022 215,224 455,842 304,304
General Banking Unit        
Net Income (GAAP)        
Interest income 838,259 840,504 1,655,088 1,649,070
Interest expense 262,310 262,556 517,534 526,575
Net interest income (a) 575,949 577,948 1,137,554 1,122,495
Provision for credit losses 15,919 7,505 26,727 108,067
Net interest income after provision for credit losses 560,030 570,443 1,110,827 1,014,428
Total noninterest income        
Securities (losses) gain, net       (228,811)
Gain on sale-leaseback, net of transaction costs       229,279
Other operating noninterest income 96,726 86,817 196,824 172,437
Total noninterest income 96,726 86,817 196,824 172,905
Total noninterest expense        
Employee salaries 144,142 135,895 286,612 271,623
Employee commissions 19,221 14,278 35,333 25,554
Employee incentives 34,119 33,623 63,776 62,389
Other salaries and benefits 35,872 36,353 73,442 73,318
Deferred loan costs (27,977) (19,987) (48,133) (36,911)
Salaries and employee benefits 205,377 200,162 411,030 395,973
Occupancy expense 43,878 41,507 86,180 77,000
Information services expense 29,136 30,155 58,840 61,517
Professional fees 5,090 4,658 10,329 9,367
Amortization of intangibles 21,041 24,048 42,345 47,879
Business development and staff related 10,639 7,182 22,001 13,692
FDIC assessment and other regulatory charges 10,753 11,469 21,010 22,727
Merger and branch consolidation related expense   24,379   92,385
Other operating expense 31,835 31,501 65,538 63,347
Total noninterest expense 357,749 375,061 717,273 783,887
Income before income tax provision 299,007 282,199 590,378 403,446
Income tax provision 68,985 66,975 134,536 99,142
Net income (GAAP) 230,022 215,224 455,842 304,304
Net Interest Margin, Non-Tax Equivalent ("Non-TE") (GAAP)        
Average interest earning assets (b) $ 61,133,759 $ 57,710,001 $ 60,670,045 $ 57,604,313
Net interest margin, non-TE ((a)/(b)) (GAAP) 3.78% 4.02% 3.78% 3.93%