Webster Financial (WBS) 10-K 27 Feb 24 2023 FY Annual report Financial data

Cover

Cover - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Feb. 23, 2024	Jun. 30, 2023
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Current Fiscal Year End Date	--12-31
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	001-31486
Entity Registrant Name	WEBSTER FINANCIAL CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	06-1187536
Entity Address, Address Line One	200 Elm Street
Entity Address, City or Town	Stamford
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06902
City Area Code	203
Local Phone Number	578-2202
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 6,500,000
Entity Common Stock, Shares Outstanding		171,753,097
Amendment Flag	false
Entity Central Index Key	0000801337
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2023
Documents Incorporated by Reference	Part III: Portions of the Proxy Statement for the Annual Meeting of Stockholders to be held on April 24, 2024 (the “Proxy Statement”).
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Common Class A [Member] | NEW YORK STOCK EXCHANGE, INC. [Member]
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	WBS
Security Exchange Name	NYSE
Preferred Stock Series F Issued | NEW YORK STOCK EXCHANGE, INC. [Member]
Entity Information [Line Items]
Title of 12(b) Security	Depositary Shares, each representing 1/1000th interest in a share
Trading Symbol	WBS-PrF
Security Exchange Name	NYSE
Preferred Stock Series G Issued | NEW YORK STOCK EXCHANGE, INC. [Member]
Entity Information [Line Items]
Title of 12(b) Security	Depositary Shares, each representing 1/40th interest in a share
Trading Symbol	WBS-PrG
Security Exchange Name	NYSE

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2023
Audit Information [Abstract]
Auditor Name	KPMG LLP
Auditor Firm ID	185
Auditor Location	New York, New York

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets:
Cash and due from banks	$ 429,323	$ 264,118
Interest-bearing deposits	1,286,472	575,825
Fair Value	8,959,729	7,892,697
Investment securities held-to-maturity, net of allowance for credit losses of $209 and $182	7,074,588	6,564,697
Federal Home Loan Bank and Federal Reserve Bank stock	326,882	445,900
Loans held for sale ($2,610 and $1,991 valued under fair value option)	6,541	1,991
Loans and leases	50,726,052	49,764,426
Allowance for credit losses on loan and leases	(635,737)	(594,741)
Loans and leases, net	50,090,315	49,169,685
Deferred tax assets, net	369,212	371,634
Property and equipment, net	429,561	430,184
Goodwill	2,631,465	2,514,104
Other intangible assets, net	203,135	199,342
Cash surrender value of life insurance policies	1,247,938	1,229,169
Accrued interest receivable and other assets	1,890,088	1,618,175
Total assets	74,945,249	71,277,521
Liabilities and stockholders' equity:
Non-interest-bearing	10,732,516	12,974,975
Interest-bearing	50,051,768	41,079,365
Total deposits	60,784,284	54,054,340
Securities sold under agreements to repurchase and other borrowings	458,387	1,151,830
Federal Home Loan Bank advances	2,360,018	5,460,552
Long-term debt	1,048,820	1,073,128
Accrued expenses and other liabilities	1,603,744	1,481,485
Total liabilities	66,255,253	63,221,335
Stockholders’ equity:
Common stock	1,828	1,828
Paid-in capital	6,179,753	6,173,240
Retained earnings	3,282,530	2,713,861
Treasury stock, at cost—10,756,089 and 8,770,472 shares	(507,523)	(431,762)
Accumulated other comprehensive (loss), net of tax	(550,571)	(684,960)
Total stockholders' equity	8,689,996	8,056,186
Total liabilities and stockholders' equity	74,945,249	71,277,521
Preferred Stock Series F Issued
Stockholders’ equity:
Preferred stock	145,037	145,037
Preferred Stock Series G Issued
Stockholders’ equity:
Preferred stock	$ 138,942	$ 138,942

Consolidated Balance Sheet (Par

Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Held-to-maturity, Allowance for Credit Loss	$ 209	$ 182
Value per share (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	3,000,000	3,000,000
Common stock par value (in usd per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	400,000,000	400,000,000
Common stock, shares issued	182,778,045	182,778,045
Treasury Stock, Common, Shares	10,756,089	8,770,472
Loans Held-for-sale, Fair Value Disclosure	$ 2,610	$ 1,991
Preferred Stock Series F Issued
Preferred Stock, Shares Outstanding	6,000	6,000
Preferred Stock, Shares Issued	6,000	6,000
Preferred Stock Series G Issued
Preferred Stock, Shares Outstanding	135,000	135,000
Preferred Stock, Shares Issued	135,000	135,000

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Interest Income:
Interest and fees on loans and leases	$ 3,071,378	$ 1,946,558	$ 762,713
Taxable interest and dividends on securities	396,681	269,233	155,902
Non-taxable interest on securities	54,207	50,442	20,884
Loans held for sale	734	78	246
Other interest and dividends	105,260	18,426	3,099
Interest income	3,628,260	2,284,737	942,844
Interest Expense:
Deposits	1,021,418	138,552	20,131
Securities sold under agreements to repurchase and other borrowings	9,102	19,059	3,040
Federal Home Loan Bank advances	222,537	58,557	1,708
Long-term debt	37,934	34,283	16,876
Interest expense	1,290,991	250,451	41,755
Net interest income	2,337,269	2,034,286	901,089
Provision (benefit) for credit losses	150,747	280,619	(54,500)
Net interest income (loss) after provision for loan and lease losses	2,186,522	1,753,667	955,589
Non-interest Income:
Deposit service fees	169,318	198,472	162,710
Loan and lease related fees	84,861	102,987	36,658
Wealth and investment services	28,999	40,277	39,586
Mortgage banking activities	1,240	705	6,219
Increase in cash surrender value of life insurance policies	26,228	29,237	14,429
Loss on sale of investment securities	(33,620)	(6,751)	0
Other income	37,311	75,856	63,770
Total non-interest income	314,337	440,783	323,372
Non-interest Expense:
Compensation and benefits	711,752	723,620	419,989
Occupancy	77,520	113,899	55,346
Technology and equipment	197,928	186,384	112,831
Intangible assets amortization	36,207	31,940	4,513
Marketing	18,622	16,438	12,051
Professional and outside services	107,497	117,530	47,235
Deposit insurance	98,081	26,574	15,794
Other expense	168,748	180,088	77,341
Total non-interest expense	1,416,355	1,396,473	745,100
Income before income tax expense	1,084,504	797,977	533,861
Income tax expense	216,664	153,694	124,997
Net income	867,840	644,283	408,864
Preferred stock dividends	(16,650)	(15,919)	(7,875)
Net income available to common shareholders, basic	851,190	628,364	400,989
Net income available to common shareholders, diluted	$ 851,190	$ 628,364	$ 400,989
Earnings per common share:
Earnings per common share, Basic (in dollars per share)	$ 4.91	$ 3.72	$ 4.43
Earnings per common share, Diluted (in dollars per share)	$ 4.91	$ 3.72	$ 4.42

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other comprehensive (loss) income, net of tax:
Net income	$ 867,840	$ 644,283	$ 408,864
Investment securities available-for-sale	113,710	(635,696)	(62,888)
Derivative instruments	6,005	(14,944)	(13,848)
Total defined benefit pension and postretirement benefit plans	14,674	(11,740)	11,900
Other comprehensive income (loss), net of tax	134,389	(662,380)	(64,836)
Comprehensive income	$ 1,002,229	$ (18,097)	$ 344,028

Consolidated Statement of Share

Consolidated Statement of Shareholder Equity Statement - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Series E Preferred Stock [Member]	Preferred Stock Series F Issued	Preferred Stock Series G Issued	Common Stock	Preferred Stock	Common Stock	Additional Paid-in Capital [Member]	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings Preferred Stock Series F Issued	Retained Earnings Preferred Stock Series G Issued	AOCI Attributable to Parent [Member]	Treasury Stock, Common
Beginning Balance at Dec. 31, 2020	$ 3,234,625						$ 145,037	$ 937	$ 1,109,532	$ 2,077,522				$ 42,256	$ (140,659)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	408,864									408,864
Other Comprehensive Income (Loss), Net of Tax	(64,836)													(64,836)
Dividends, Common Stock	(145,223)									(145,223)
Dividends, Preferred Stock			$ (7,875)									$ (7,875)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	13,662								4,235	0					9,427
Stock Issued During Period, Value, Stock Options Exercised	3,492								(5,173)						8,665
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(4,384)														(4,384)
Ending Balance at Dec. 31, 2021	3,438,325						145,037	937	1,108,594	2,333,288				(22,580)	(126,951)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared						$ 1.60
Preferred Stock, Dividends Per Share, Declared			$ 1,312.5
Net income	644,283									644,283
Other Comprehensive Income (Loss), Net of Tax	(662,380)													(662,380)
Dividends, Common Stock	(247,791)									(247,791)
Dividends, Preferred Stock				$ (7,875)	$ (8,044)							(7,875)	$ (8,044)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	54,099								26,748						27,351
Stock Issued During Period, Value, Stock Options Exercised	703								(692)						1,395
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(23,655)														(23,655)
Stock Issued During Period, Value, Acquisitions	5,180,124						138,942	891	5,040,291
Stock Issued During Period, Value, Charitable Contributions	10,500								(1,701)						12,201
Stock Repurchased During Period, Value	(322,103)														(322,103)
Ending Balance at Dec. 31, 2022	$ 8,056,186	$ (4,245)					283,979	1,828	6,173,240	2,713,861	$ (4,245)			(684,960)	(431,762)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared						1.60
Preferred Stock, Dividends Per Share, Declared				$ 1,312.5	$ 65
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2016-13 [Member]
Net income	$ 867,840									867,840
Other Comprehensive Income (Loss), Net of Tax	134,389													134,389
Dividends, Common Stock	(278,276)									(278,276)
Dividends, Preferred Stock				$ (7,875)	$ (8,775)							$ (7,875)	$ (8,775)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	54,087								8,539						45,548
Stock Issued During Period, Value, Stock Options Exercised	1,723								(2,026)						3,749
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(16,278)														(16,278)
Stock Repurchased During Period, Value	(108,780)														(108,780)
Ending Balance at Dec. 31, 2023	$ 8,689,996						$ 283,979	$ 1,828	$ 6,179,753	$ 3,282,530				$ (550,571)	$ (507,523)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared						$ 1.60
Preferred Stock, Dividends Per Share, Declared				$ 1,312.5	$ 65

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Activities:
Net income	$ 867,840	$ 644,283	$ 408,864
Adjustments to reconcile net income to net cash provided by operating activities:
Provision (benefit) for credit losses	150,747	280,619	(54,500)
Deferred tax expense (benefit)	(53,634)	(69,664)	(4,998)
Stock-based compensation	54,087	54,099	13,662
Common stock contribution to charitable foundation	0	10,500	0
Depreciation and amortization	76,490	81,800	35,913
Amortization of earning assets and funding premium/discount, net	(23,267)	(26,215)	133,069
Amortization of low-income housing tax credit investments	71,775	44,208	3,918
Amortization of mortgage servicing rights	1,063	870	5,593
Increase (Decrease) in Leasing Receivables	(30,616)	(56,783)	(22,781)
Gain on sale, net of write-down, on foreclosed and repossessed assets	(337)	(1,130)	(744)
Loss (gain) on sale, net of write-down, on premises and equipment	4,020	8,293	(1,236)
Loss on sale of investment securities	33,620	6,751	0
Originations of loans held for sale	(13,319)	(33,107)	(235,066)
Proceeds from sale of loans held for sale	13,882	36,335	247,634
Net (gain) on mortgage banking activities	(1,126)	(580)	(5,912)
Net (gain) on sale of loans not originated for sale	(860)	(3,322)	(3,862)
Increase in cash surrender value of life insurance policies	(26,228)	(29,237)	(14,429)
Gain from life insurance policies	(3,566)	(6,311)	(4,402)
Net decrease (increase) in derivative contract assets net of liabilities	(73,295)	536,820	173,506
Net (increase) decrease in accrued interest receivable and other assets	(13,774)	(106,740)	(69,263)
Net (decrease) increase in accrued expenses and other liabilities	(116,085)	(149,103)	38,064
Net cash provided by operating activities	978,649	1,335,952	688,592
Investing Activities:
Purchases of available-for-sale securities	(2,372,249)	(1,099,810)	(1,957,562)
Proceeds from maturities and principal payments of available-for-sale securities	591,207	754,545	935,621
Proceeds from sales of available-for-sale securities	789,603	172,947	0
Purchases of held-to-maturity securities	(891,761)	(1,150,023)	(1,968,133)
Proceeds from maturities and principal payments of held-to-maturity securities	390,073	750,752	1,288,140
Net proceeds from (purchase of) Federal Home Loan Bank stock	119,018	(223,562)	5,758
Purchases of intercompany debt securities	(27,430)	(24,887)	(11,361)
Net (increase) in loans	(1,653,257)	(7,501,545)	(773,443)
Proceeds from loans not originated for sale	625,968	679,693	82,187
Proceeds from the sale of foreclosed properties and repossessed assets	4,033	2,568	1,998
Proceeds from the sale of premises and equipment	6,894	300	3,221
Additions to premises and equipment	(40,303)	(28,762)	(16,589)
Proceeds from life insurance policies	20,098	21,893	5,074
Net cash (used in) provided by investing activities	(2,595,752)	(7,186,338)	(2,405,089)
Financing Activities:
Net increase in deposits	6,721,028	936,001	2,511,163
Proceeds From (Payments) To FHLBank Borrowings, Financing Activities	(3,100,534)	5,449,555	(122,167)
Proceeds From Extinguishment Of Debt	0	2,548	0
Net increase (decrease) in securities sold under agreements to repurchase and other borrowings	(693,443)	447,202	(320,459)
Repayments of Other Long-Term Debt	(16,752)	0	0
Dividends paid to common shareholders	(278,155)	(247,767)	(144,807)
Dividends paid to preferred shareholders	(16,650)	(13,725)	(7,875)
Exercise of stock options	1,723	703	3,492
Common stock repurchased	(107,984)	(322,103)	0
Common shares acquired related to stock compensation plan activity	(16,278)	(23,655)	(4,384)
Net cash (used in) financing activities	2,492,955	6,228,759	1,914,963
Net increase (decrease) in cash and cash equivalents	875,852	378,373	198,466
Cash and cash equivalents, beginning of period	839,943	461,570	263,104
Cash and cash equivalents, at end of period	1,715,795	839,943	461,570
Supplemental disclosure of cash flow information:
Interest paid	1,248,620	240,851	42,151
Income taxes paid	268,598	193,544	112,587
Noncash investing and financing activities:
Transfer of loans and leases to foreclosed properties and repossessed assets	10,485	774	1,757
Transfer of returned finance lease equipment to assets held for sale	5,139	0	0
Transfer of loans from portfolio to loans held for sale	629,172	652,855	78,316
Deposits assumed	0	313	0
Sterling
Adjustments to reconcile net income to net cash provided by operating activities:
Provision (benefit) for credit losses	175,100
Investing Activities:
Net (increase) decrease in interest-bearing deposits	0	513,960	0
Noncash investing and financing activities:
Noncash or Part Noncash Acquisition, Fixed Assets Acquired	17,607	26,922,010	0
Noncash or Part Noncash Acquisition, Intangible Assets Acquired	(25,561)	(2,149,865)	0
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	(7,954)	(24,405,711)	0
Stock Issued	0	5,041,182	0
Sterling | Preferred Stock
Noncash investing and financing activities:
Total consideration	0	138,942	0
Bend Financial, Inc.
Investing Activities:
Payments to Acquire Businesses, Net of Cash Acquired	0	(54,407)	0
Noncash investing and financing activities:
Noncash or Part Noncash Acquisition, Fixed Assets Acquired	294	15,731	0
Noncash or Part Noncash Acquisition, Intangible Assets Acquired	(294)	(38,966)	0
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	0	(290)	0
interLINK
Investing Activities:
Payments to Acquire Businesses, Net of Cash Acquired	(157,646)	0	0
Noncash investing and financing activities:
Noncash or Part Noncash Acquisition, Fixed Assets Acquired	6,417	0	0
Noncash or Part Noncash Acquisition, Value of Liabilities Assumed	(15,948)	0	0
Noncash or Part Noncash Acquisition, Other Liabilities Assumed	16,039	0	0
Noncash or Part Noncash Acquisition, Goodwill And Other Intangible Assets Acquired	$ 183,216	$ 0	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Nature of Operations Webster Financial Corporation is a bank holding company and financial holding company under the BHC Act, incorporated under the laws of Delaware in 1986, and headquartered in Stamford, Connecticut. Webster Bank, and its HSA Bank Division, is a leading commercial bank in the Northeast that provides a wide range of digital and traditional financial solutions across three differentiated lines of business: Commercial Banking, HSA Bank, and Consumer Banking. While its core footprint spans the northeastern U.S. from New York to Massachusetts, certain businesses operate in extended geographies. HSA Bank is one of the largest providers of employee benefits solutions in the U.S. Basis of Presentation The Consolidated Financial Statements have been prepared in accordance with GAAP, and include the accounts of the Company and all other entities in which the Company has a controlling financial interest. Intercompany transactions and balances have been eliminated in consolidation. Assets under administration or assets under management that the Company holds or manages in a fiduciary or agency capacity for customers are not included on the accompanying Consolidated Balance Sheets. Certain prior period amounts have been reclassified to conform to the current year's presentation. These reclassifications did not have a significant impact on the Company's Consolidated Financial Statements. Principles of Consolidation The purpose of Consolidated Financial Statements is to present the results of operations and the financial position of the Company and its subsidiaries as if the consolidated group were a single economic entity. In accordance with the applicable accounting guidance for consolidations, the Consolidated Financial Statements include any VOE in which the Company has a controlling financial interest and any VIE for which the Company is deemed to be the primary beneficiary. The Company generally consolidates its VOEs if the Company, directly or indirectly, owns more than 50% of the outstanding voting shares of the entity, and if the non-controlling stockholders do not hold any substantive participating or controlling rights. The Company evaluates VIEs to understand the purpose and design of the entity, and its involvement in the ongoing activities of the VIE, and will consolidate the VIE if it has (i) the power to direct the activities of the VIE that most significantly affect the VIE's economic performance, and (ii) an obligation to absorb losses of the VIE, or the right to receive benefits from the VIE, that could potentially be significant to the VIE. The Company accounts for unconsolidated partnerships and certain other investments using the equity method of accounting if it has the ability to significantly influence the operating and financial policies of the investee. This is generally presumed to exist when the Company owns between 20% and 50% of a corporation, or when it has greater than 3% to 5% interest in a limited partnership or similarly structured entity. Additional information regarding consolidated and non-consolidated VIEs can be found within Note 15: Variable Interest Entities. Use of Estimates The preparation of the Consolidated Financial Statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Business Combinations Business combinations are accounted for under the acquisition method, in which the identifiable assets acquired and liabilities assumed are generally measured and recognized at fair value as of the acquisition date, with the excess of the purchase price over the fair value of the net assets acquired recognized as goodwill. Items such as acquired ROU lease assets and operating lease liabilities as lessee, employee benefit plans, and income-tax related balances are recognized in accordance with other applicable GAAP, which may result in measurements that differ from fair value. After the adoption of ASU No. 2021-08—Business Combinations (Topic 805)—Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, contract assets and contract liabilities from contracts with customers discussed below, may result in measurements that differ from fair value as well. Business combinations are included in the Consolidated Financial Statements from the respective dates of acquisition. Historical reporting periods reflect only the results of legacy Webster operations. Merger-related costs are expensed in the period incurred and presented within the applicable non-interest expense category. Additional information regarding the Company's mergers and acquisitions can be found within Note 2: Mergers and Acquisitions. Cash and Cash Equivalents Cash and cash equivalents is comprised of cash and due from banks and interest-bearing deposits. Cash equivalents have an original maturity of three months or less. Cash and due from banks includes cash on hand, certain deposits at the FRB, and cash due from banks. Restricted cash related to Federal Reserve System requirements and cash collateral received on derivative positions are also included in Cash and due from banks. Interest-bearing deposits includes deposits at the FRB in excess of reserve requirements, if any, and federal funds sold to other financial institutions. Investments in Debt Securities Debt security transactions are recognized on the trade date, which is the date the order to buy or sell the security is executed. Investments in debt securities are classified as available-for-sale or held-to-maturity at the time of purchase. Any classification change subsequent to the trade date is reviewed for compliance with corporate objectives and accounting policies. Debt securities classified as available-for-sale are recorded at fair value with unrealized gains and losses recorded as a component of (AOCL). If a debt security is transferred from available-for-sale to held-to-maturity, it is recorded at fair value at the time of transfer and any respective gain or loss would be recorded as a separate component of (AOCL) and amortized as an adjustment to interest income over the remaining life of the security. Debt securities classified as available-for-sale are reviewed for credit losses when the fair value of a security falls below the amortized cost basis and the decline is evaluated to determine if any portion is attributable to credit loss. The decline in fair value attributable to credit loss is recorded directly to earnings, with a corresponding allowance for credit loss, limited to the amount that fair value is less than the amortized cost. If the credit quality subsequently improves, previously recorded allowance amounts may be reversed. An available-for-sale debt security will be placed on non-accrual status if collection of principal and interest in accordance with contractual terms is doubtful. When the Company intends to sell an impaired available-for-sale debt security, or if it is more likely than not that the Company will be required to sell the security prior to recovery of the amortized cost basis, the entire fair value adjustment will immediately be recognized in earnings through non-interest income. The gain or loss on sale is calculated using the carrying value plus any related (AOCL) balance associated with the securities sold. Debt securities classified as held-to-maturity are those in which the Company has the ability and intent to hold to maturity. Debt securities classified as held-to-maturity are recorded at amortized cost net of unamortized premiums and discounts. Discount accretion income and premium amortization expense are recognized as interest income using the effective interest method, with consideration given to prepayment assumptions on mortgage-backed securities. Premiums are amortized to the earliest call date for debt securities purchased at a premium, with explicit, non-contingent call features and are callable at a fixed price and preset date. Debt securities classified as held-to-maturity are reviewed for credit losses under the CECL model with an allowance recorded on the balance sheet for expected lifetime credit losses. The ACL is calculated on a pooled basis using statistical models which include forecasted scenarios of future economic conditions. Forecasts revert to long-run loss rates implicitly through the economic scenario, generally over three years. If the risk for a particular security no longer matches the collective assessment pool, it is removed and individually assessed for credit deterioration. The non-accrual policy for held-to-maturity debt securities is the same as for available-for-sale debt securities. A zero credit loss assumption is maintained for U.S. Treasuries and agency-backed securities in both the available-for-sale and held-to-maturity portfolios, as applicable. This assumption is subject to quarterly review to ensure it remains appropriate. Additional information regarding investments in debt securities can be found within Note 3: Investment Securities. Investments in Equity Securities The Company’s accounting treatment for non-consolidated equity investments differs for those with and without readily determinable fair values. Equity investments with readily determinable fair values are recorded at fair value with changes in fair value recorded in non-interest income. For equity investments without readily determinable fair values, the Company elected the measurement alternative, and therefore carries these investments at cost, less impairment, if any, plus or minus changes in observable prices. Certain equity investments that do not have a readily available fair value may qualify for NAV measurement based on specific requirements. The Company's alternative investments accounted for at NAV consist of investments in non-public entities that generally cannot be redeemed since the Company’s investments are distributed as the underlying equity is liquidated. On a quarterly basis, the Company reviews its equity investments without readily determinable fair values for impairment. If the equity investment is considered impaired, an impairment loss equal to the amount by which the carrying value exceeds its fair value is recorded through a charge to earnings. The impairment loss may be reversed in a subsequent period if there are observable transactions for the identical or similar investment of the same issuer at a higher amount than the carrying amount that was established when the impairment was recognized. Impairments, as well as upward or downward adjustments resulting from observable price changes in orderly transactions for identical or similar investments, are included in non-interest income. Equity investments in entities that finance affordable housing and other community development projects provide a return primarily through the realization of tax benefits. The Company applies the proportional amortization method to account for its investments in qualified affordable housing projects. Investment in Federal Home Loan Bank and Federal Reserve Bank Stock The Bank is a member of the FHLB and the Federal Reserve System, and is required to maintain an investment in capital stock of both the FHLB and FRB. Based on redemption provisions, FHLB and FRB stock has no quoted market value and is carried at cost. Membership stock is reviewed for impairment if economic circumstances would warrant review. Loans Held for Sale Loans that are classified as held for sale at the time of origination are accounted for under the fair value option. Loans not originated for sale but subsequently transferred to held for sale are valued at the lower of cost or fair value on an individual asset basis. Any cost amount in excess of fair value is recorded as a valuation allowance and recognized as a reduction of other non-interest income. Gains or losses on the sale of loans held for sale are recorded either as part of Mortgage banking activities or Other income on the accompanying Consolidated Statements of Income. Cash flows from the sale of loans that were originated for sale are presented within Operating activities on the accompanying Consolidated Statements of Cash Flows, whereas cash flows from the sale of loans that were originated for investment and then subsequently transferred to held for sale are presented within Investing activities. Additional information regarding mortgage banking activities and loans sold can be found within Note 5: Transfers and Servicing of Financial Assets. Transfers and Servicing of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is generally considered to have been surrendered when: (i) the transferred assets are legally isolated from the Company or its consolidated affiliates, even in bankruptcy or other receivership, (ii) the transferee has the right to pledge or exchange the assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Company, and (iii) the Company does not maintain the obligation or unilateral ability to reclaim or repurchase the assets. The Company sells financial assets in the normal course of business, the majority of which are residential mortgage loan sales to government-sponsored enterprises through established programs, as well as commercial loan sales through participation agreements, and other individual or portfolio loan and securities sales. In accordance with the accounting guidance for asset transfers, the Company considers any ongoing involvement with transferred assets in determining whether the assets can be derecognized from the balance sheet. With the exception of servicing, the Company’s continuing involvement with financial assets sold is minimal, and generally is limited to market customary representation and warranty clauses covering certain characteristics of the mortgage loans that were sold, and the Company's origination process. The gain or loss on sale depends on the previous carrying amount of the transferred financial assets, the consideration received, and any other assets obtained or liabilities incurred in exchange for the transferred assets. When the Company sells financial assets, it may retain servicing rights and/or other interests in the financial assets. Servicing assets and any other interests held by the Company are recorded at fair value upon transfer, and subsequently carried at the lower of cost or fair value. Additional information regarding transfers of financial assets and mortgage servicing assets can be found within Note 5: Transfers and Servicing of Financial Assets. Loans and Leases Loans and leases are stated at the principal amount outstanding, net of amounts charged-off, unamortized premiums and discounts, and deferred loan and lease fees or costs, which are recognized as yield adjustments in interest income using the effective interest method. These yield adjustments are amortized over the contractual life of the related loans and leases and are adjusted for prepayments, as applicable. Interest on loans and leases is credited to interest income as earned based on the interest rate applied to principal amounts outstanding. Amounts of cash receipts and cash payments for loans and leases are presented net within Investing activities on the Consolidated Statements of Cash Flows. Non-accrual Loans Loans are placed on non-accrual status when full collection of principal and interest in accordance with contractual terms is not expected based on available information, which generally occurs when principal or interest payments become 90 days delinquent unless the loan is well secured and in the process of collection, or sooner if circumstances indicate that the borrower may be unable to meet contractual principal or interest payments. The Company considers a loan to be “well-secured” when it is secured by collateral in the form of liens on or pledges of real or personal property that have a realizable value sufficient to discharge the debt in full, or when it is secured by a contractual guarantee of a financially responsible party. The Company considers a loan “in the process of collection” if collection of the debt is proceeding in due course either through legal action or through collection efforts not involving legal action that are reasonably expected to result in repayment of the debt or in its restoration to a current status in the near future. When loans and leases are placed on non-accrual status, the accrual of interest income and the amortization or accretion of premiums, discounts, and deferred fees and costs is discontinued, and any previously accrued interest is reversed as a reduction of interest income. For commercial loans and leases, if the Company determines that repayment of non-accrual loans and leases is not expected, any payment received is applied to principal until the unpaid balance has been fully recovered. Any excess is then credited to interest income. For consumer loans, if the Company determines that principal can be repaid, interest payments are taken into income as received on a cash basis. Loans are generally removed from non-accrual status when they become current as to principal and interest or demonstrate a period of performance under the contractual terms and, in the opinion of management, are fully collectible as to principal and interest. For commercial loans, a sustained period of repayment performance is generally required. Pursuant to regulatory guidance, a loan discharged under Chapter 7 of the U.S. bankruptcy code is removed from non-accrual status when full repayment of the remaining pre-discharged contractual principal and interest is expected, and there have been at least six consecutive months of current payments. Additional information regarding non-accrual loans and leases can be found within Note 4: Loans and Leases. Allowance for Credit Losses on Loans and Leases The ACL on loans and leases, which is established through a provision charged to expense, is a contra-asset account that offsets the amortized cost basis of loans and leases for the credit losses that are expected to occur over the life of the asset. Executive management reviews and advises on the adequacy of the allowance, which is maintained at a level that management deems to be sufficient to cover expected credit losses within the loan and lease portfolios. The Company has elected to present accrued interest receivable separately from the amortized cost basis of Loans and leases on the accompanying Consolidated Balance Sheets. An ACL on accrued interest for a loan is not measured as accrued interest income is reversed against interest income for non-accrual loans immediately after their non-accrual classification. The ACL on loans and leases is determined using the CECL model, whereby an expected lifetime credit loss is recognized at the origination or purchase of an asset, including those acquired through a business combination, which is then reassessed at each reporting date over the contractual life of the asset. The calculation of expected credit losses includes consideration of past events, current conditions, and reasonable and supportable economic forecasts that affect the collectability of the reported amounts. Generally, expected credit losses are determined through a pooled, collective assessment of loans and leases with similar risk characteristics. However, if the risk characteristics of a loan or lease change such that it no longer matches that of the collectively assessed pool, it is removed from the population and individually assessed for credit losses. The total ACL on loans and leases recorded by management represents the aggregated estimated credit loss determined through both the collective and individual assessments. Collectively Assessed Loans and Leases. Collectively assessed loans and leases are segmented based on product type and credit quality, and expected losses are determined using a PD, LGD, EAD, or loss rate framework. For portfolios using the PD, LGD, and EAD framework, expected credit losses are calculated as the product of the probability of a loan defaulting, expected loss given the occurrence of a default, and the expected exposure of a loan at default. Summing the product across loans over their lives yields the lifetime expected credit losses for a given portfolio. The Company’s PD and LGD calculations are predictive models that measure the current risk profile of the loan pools using forecasts of future macroeconomic conditions, historical loss information, loan-level risk attributes, and credit quality indicators. The calculation of EAD follows an iterative process to determine the expected remaining principal balance of a loan based on historical paydown rates for loans of a similar segment within the same portfolio. The calculation of portfolio exposure in future quarters incorporates expected losses, the loan's amortization schedule, and prepayment rates. Under the loss rate framework, expected credit losses are estimated using a loss rate that is multiplied by the amortized cost of the asset at the balance sheet date. For each loan segment identified, management applies an expected historical loss trend based on third-party loss estimates, and correlates them to observed economic metrics, and reasonable and supportable forecasts of economic conditions. The Company’s models incorporate a single economic forecast scenario and macroeconomic assumptions over a reasonable and supportable forecast period. The development of the reasonable and supportable forecast period assumes that each macroeconomic variable will revert to long-term expectations, with reversion characteristics unique to specific economic indicators and forecasts. Reversion towards long-term expectations generally begins two to three years from the forecast start date and is complete within three to five years. Certain models use output reversion and revert to mean historical loss rates on a straight-line basis in the third year of the forecast. Other models incorporate a reasonable and supportable forecast of various macroeconomic variables over the remaining life of the Company's assets. Historical loss rates are based on approximately 10 years of recently available data and are updated annually. Macroeconomic variables are used as inputs to the loss models and are selected based on the correlation of the variables to credit losses for each class of financing receivable as follows: the commercial models use unemployment, gross domestic product, commercial real estate price indices, and retail sales (for commercial unfunded); the residential model uses the Case-Shiller Home Price Index; the home equity loan and line of credit models use interest rate spreads between U.S. Treasuries and corporate bonds and, in addition, the home equity loan model also uses the Federal Housing Finance Agency Home Price Index; and the personal loan and credit line models use the Case-Shiller Home Price Index and Federal Housing Finance Agency Home Price Index. Forecasted economic scenarios are sourced from a third party. Data from the baseline forecast scenario is used as the input to the modeled loss calculation. Changes in forecasts of macroeconomic variables will impact expectations of lifetime credit losses calculated by the loss models. However, the impact of changes in macroeconomic forecasts may be different for each portfolio and will reflect the credit quality and nature of the underlying assets at that time. A portion of the collective ACL is comprised of qualitative adjustments for risk characteristics that are not reflected or captured in the quantitative models, but are likely to impact the measurement of estimated credit losses. Qualitative factors are based on management's judgement of the Company, market, industry, or business specific data including loan trends, portfolio segment composition, and loan rating or credit scores. Qualitative adjustments may be applied in relation to economic forecasts when relevant facts and circumstances are expected to impact credit losses, particularly in times of significant volatility in economic activity. In addition to the above considerations, the ACL calculation includes expectations of prepayments and recoveries. Extensions, renewals, and modifications are not included in the collective assessment. Individually Assessed Loans and Leases. When loans and leases no longer match the ri sk characteristics of the collectively assessed pool, they are removed from the collectively assessed population and individually assessed for credit losses. Generally, all non-accrual loans and loans with a charge-off are individually assessed. Individual assessment for commercial loans that are considered to be collateral dependent is based on the fair value of the collateral less estimated cost to sell, the present value of the expected cash flows from the operation of the collateral, or a scenario weighted approach of both of these methods. If a loan is not collateral dependent, the individual assessment is based on a discounted cash flow approach. For collateral dependent commercial loans and leases, the Company's process requires the Company to determine the fair value of the collateral by obtaining a third-party appraisal or asset valuation, an interim valuation analysis, blue book reference, or other internal methods. Fair value of the collateral for commercial loans is reevaluated quarterly. Whenever the Company has a third-party real estate appraisal performed by independent licensed appraisers, a licensed in-house appraisal officer or qualified individual reviews these appraisals for compliance with the Financial Institutions Reform Recovery and Enforcement Act and the Uniform Standards of Professional Appraisal Practice. Individual assessments for residential and home equity loans are based on a discounted cash flow approach or the fair value of collateral less the estimated costs to sell. Other consumer loans are individually assessed using a loss factor approach based on historical loss rates. For residential and consumer collateral dependent loans, a third-party appraisal is obtained upon loan default. Fair value of the collateral for residential and consumer collateral dependent loans is reevaluated every six months, by either obtaining a new appraisal or other internal valuation method. Fair value is also reassessed, with any excess amount charged off, for residential and home equity loans that reach 180 days past due per Federal Financial Institutions Examination Council guidelines. A fair value shortfall relative to the amortized cost balance is reflected as a valuation allowance within the ACL on loans and leases. Subsequent to an appraisal or other fair value estimate, should reliable information come to management's attention that the value has declined further, an additional allowance may be recorded to reflect the particular situation, thereby increasing the ACL on loans and leases. If the credit quality subsequently improves, the allowance is reversed up to a maximum of the previously recorded credit losses. Any individually assessed loan for which no specific valuation allowance is necessary is the result of either sufficient cash flow or sufficient collateral coverage relative to the amortized cost. Additional information regarding the ACL on loans and leases can be found within Note 4: Loans and Leases. Charge-off of Uncollectible Loans If all or a portion of a loan is deemed to be no longer collectible upon the occurrence of a loss-confirming event, a charge-off may be recognized. Charge-offs reduce the amortized cost basis of the loan with a corresponding reduction to the ACL. For commercial loans, loss confirming events usually involve the receipt of specific adverse information about the borrower. The Company will generally recognize charge-offs for commercial loans on a case-by-case basis based on the review of the entire credit relationship and financial condition of the borrower. Loss-confirming events for consumer loans, such as bankruptcy or protracted delinquency, are typically based on established thresholds rather than by specific adverse information about the borrower. PCD Loans and Leases PCD loans and leases are defined as those that have experienced a more-than-insignificant deterioration in credit quality since origination. The Company considers a variety of factors to evaluate and identify whether acquired loans are PCD, including but not limited to, nonaccrual status, delinquency, whether the borrower is experiencing financial difficulty, partial charge-offs, decreases in FICO scores, risk rating downgrades, and other factors. Upon acquisition, expected credit losses are added to the fair value of individual PCD loans and leases to determine the amortized cost basis. After initial recognition, any changes to the estimate of expected credit losses, favorable or unfavorable, are recorded as a provision for credit loss during the period of change. PCD accounting is also applied to loans and leases previously charged-off by the acquiree if the Company has contractual rights to the cash flows at the acquisition date. The Company recognizes an additional ACL for amounts previously charged-off by the acquiree with a corresponding increase to the amortized costs basis of the acquired asset. Balances deemed to be uncollectible are immediately charged-off in accordance with the Company’s charge-off policies, resulting in the establishment of the initial ACL for PCD loans and leases to be recorded net of these uncollectible balances. Allowance for Credit Losses on Unfunded Loan Commitments The ACL on unfunded loan commitments provides for potential exposure inherent with funding the unused portion of legal commitments to lend that are not unconditionally cancellable by the Company. Accounting for unfunded loan commitments follows the CECL model. The calculation of the allowance includes the probability of funding to occur and a corresponding estimate of expected lifetime credit losses on amounts assumed to be funded. Loss calculation factors are consistent with the ACL methodology for funded loans using the PD and LGD applied to the underlying borrower risk and facility grades, a draw down factor applied to utilization rates, relevant forecast information, and management's qualitative factors. The ACL on unfunded credit commitments is included within Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets. Additional information regarding the ACL on unfunded loan commitments can be found within Troubled Debt Restructurings Prior to the adoption of ASU No. 2022-02—Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures, a modified loan was considered a TDR when the following two conditions were met: (i) the borrower was experiencing financial difficulty, and (ii) the modification constituted a concession (i.e., the modified terms of the loan were more attractive to the borrower than standard market terms). The Company's most common types of TDRs included covenant modifications and forbearance. The Company’s policy was to place consumer loan TDRs, except those that were performing prior to TDR classification, on non-accrual status for a minimum period of six months. Commercial loan TDRs were evaluated on a case-by-case basis when determining whether or not to place them on non-accrual status. Loans qualified for return-to-accrual status when the borrower had demonstrated performance with the restructured terms of the loan agreement for a minimum period of six months. TDRs were also to be reported as such for the remaining life of the loan and individually assessed for expected credit losses under the Company’s ACL methodology. Upon adoption of ASU No. 2022-02 on January 1, 2023, the existing measurement and disclosure requirements for TDRs by creditors were eliminated and disclosure requirements for certain loan refinancings and restructurings by creditors when a borrower is experiencing financial difficulty were enhanced. Additional information regarding modifications to borrowers experiencing financial difficulty can be found under the section captioned “Accounting Standards Adopted During the Current Year” and within Note 4: Loans and

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Variable Interest Entities The Company has an investment interest in the following entities that each meet the definition of a variable interest entity. Information regarding the Company's consolidation of variable interest entities can be found within Note 1: Summary of Significant Accounting Policies. Consolidated Rabbi Trusts. The Company established a Rabbi Trust to meet its obligations due under the Webster Bank Deferred Compensation Plan for Directors and Officers and to mitigate expense volatility. The funding of the Rabbi Trust and the discontinuation of the Webster Bank Deferred Compensation Plan for Directors and Officers occurred during 2012. In connection with the Sterling merger in 2022, the Company acquired assets held in a separate Rabbi Trust that had been previously established to fund obligations due under the Greater New York Savings Bank Directors' Retirement Plan. Investments held in the Rabbi Trusts consist primarily of mutual funds that invest in equity and fixed income securities. The Company is considered the primary beneficiary of these Rabbi Trusts as it has the power to direct the activities of the Rabbi Trusts that most significantly impact its economic performance and it has the obligation to absorb losses and/or the right to receive benefits of the Rabbi Trusts that could potentially be significant. The Rabbi Trusts' assets are included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. Investment earnings and any changes in fair value are included in Other income on the accompanying Consolidated Statements of Income. Additional information regarding the Rabbi Trusts' investments can be found within Note 18: Fair Value Measurements. Non-Consolidated Low Income Housing Tax Credit Investments. The Company makes non-marketable equity investments in entities that sponsor affordable housing and other community development projects that qualify for the LIHTC Program pursuant to Section 42 of the Internal Revenue Code. The purpose of these investments is not only to assist the Bank in meeting its responsibilities under the CRA, but also to provide a return, primarily through the realization of tax benefits. While the Company's investment in an entity may exceed 50% of its outstanding equity interests, the entity is not consolidated as the Company is not the primary beneficiary. The Company has determined that it is not the primary beneficiary due to its inability to direct the activities that most significantly impact economic performance. The Company applies the proportional amortization method to subsequently measure its investments in qualified affordable housing projects. The following table summarizes the Company's LIHTC investments and related unfunded commitments: At December 31, (In thousands) 2023 2022 Gross investment in LIHTC investments $ 1,135,192 $ 797,453 Accumulated amortization (141,199) (69,424) Net investment in LIHTC investments $ 993,993 $ 728,029 Unfunded commitments for LIHTC investments $ 549,258 $ 335,959 The aggregate carrying value of the Company's LIHTC investments is included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets and represents the Company's maximum exposure to loss. The related unfunded commitments are included in Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets. There were $334.9 million and $211.8 million of net commitments approved to fund LIHTC investments during the years ended December 31, 2023, and 2022. Webster Statutory Trust. The Company owns all the outstanding common stock of Webster Statutory Trust, a financial vehicle that has issued, and in the future may issue, trust preferred securities. The Company is not the primary beneficiary of Webster Statutory Trust. Webster Statutory Trust's only assets are junior subordinated debentures that are issued by the Company, which were acquired using the proceeds from the issuance of trust preferred securities and common stock. The junior subordinated debentures are included in Long-term debt on the accompanying Consolidated Balance Sheets, and the related interest expense is included in Long-term debt on the accompanying Consolidated Statements of Income. Additional information regarding these junior subordinated debentures can be found within Note 11: Borrowings. Other Non-Marketable Investments. The Company invests in alternative investments comprising interests in non-public entities that cannot be redeemed since the investment is distributed as the underlying equity is liquidated. The ultimate timing and amount of these distributions cannot be predicted with reasonable certainty. For each of these alternative investments that is classified as a variable interest entity, the Company has determined that it is not the primary beneficiary due to its inability to direct the activities that most significantly impact economic performance. The aggregate carrying value of the Company's other

Mergers and Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2023
Business Combination and Asset Acquisition [Abstract]
Mergers and Acquisitions	Mergers and Acquisitions Merger with Sterling On January 31, 2022, the Company completed its merger with Sterling pursuant to an Agreement and Plan of Merger dated as of April 18, 2021. Pursuant to the merger agreement, Sterling Bancorp merged with and into the Holding Company, with the Holding Company continuing as the surviving corporation. Following the merger, on February 1, 2022, Sterling National Bank, a wholly-owned subsidiary of Sterling Bancorp, merged with and into the Bank, with the Bank continuing as the surviving bank. Sterling was a full-service regional bank headquartered in Pearl River, New York, that primarily served the Greater New York metropolitan area. The merger expanded the Company's geographic footprint and combined two complementary organizations to create one of the largest commercial banks in the northeastern U.S. Pursuant to the merger agreement, each share of Sterling common stock issued and outstanding immediately prior to the merger, other than certain shares held by the Company and Sterling, was converted into the right to receive a fixed 0.4630 share of Webster common stock. Furthermore, certain equity awards granted under Sterling's equity compensation plans were converted into a corresponding award with respect to Webster common stock, generally subject to the same terms and conditions, with the number of shares underlying such awards adjusted based on the 0.4630 fixed exchange ratio. Cash was also paid to Sterling common stockholders in lieu of fractional shares, as applicable. In addition, each share of Sterling 6.50% Series A Non-Cumulative Perpetual Preferred Stock issued and outstanding immediately prior to the merger was converted into the right to receive one share of newly created Webster 6.50% Series G Non-Cumulative Perpetual Preferred Stock, having substantially the same terms. The following table summarizes the determination of the purchase price consideration: (In thousands, except share and per share data) Webster common stock issued 87,965,239 Price per share of Webster common stock on January 31, 2022 $ 56.81 Consideration for outstanding common stock 4,997,305 Consideration for preferred stock exchanged 138,942 Consideration for replacement equity awards (1) 43,877 Cash in lieu of fractional shares 176 Total purchase price consideration $ 5,180,300 (1) The fair value of the replacement equity awards issued by the Company and included in the consideration transferred pertains to services performed prior to the merger effective date. The fair value attributed to services performed after the merger effective date is being recognized over the required service vesting period for each award and recorded as Compensation and benefits expense on the accompanying Consolidated Statements of Income. During the years ended December 31, 2023, and 2022, the Company recognized an increase of $22.8 million and $18.8 million in stock compensation expense related to the replacement equity awards. The merger was accounted for as a business combination. Accordingly, the purchase price was allocated to the assets acquired and liabilities assumed based on their fair values as of the merger effective date. The determination of fair value requires management to make estimates about discount rates, future expected cash flows, market conditions, and other future events that are highly subjective in nature and are subject to change. Fair value estimates of the assets acquired and liabilities assumed were subject to adjustment during the one-year measurement period following the closing date of the merger if new information was obtained about facts and circumstances that existed as of the merger effective date that, if known, would have affected the measurement of the amounts recognized as of that date. Measurement period adjustments pertaining to other assets and other liabilities and their deferred tax impact were made during the first quarter of 2023, totaling a net $25.6 million. The Company's valuations of the assets acquired and liabilities assumed in the merger with Sterling were considered final as of March 31, 2023. The following table summarizes the final allocation of the purchase price to the fair value of the identifiable assets acquired and liabilities assumed from Sterling: (In thousands) Unpaid Principal Balance Fair Value Purchase price consideration $ 5,180,300 Assets: Cash and due from banks 510,929 Interest-bearing deposits 3,207 Investment securities available-for-sale 4,429,948 Federal Home Loan Bank and Federal Reserve Bank Stock 150,502 Loans held for sale 23,517 Loans and leases: Commercial non-mortgage $ 5,570,782 5,527,657 Asset-based 694,137 683,958 Commercial real estate 6,790,600 6,656,405 Multi-family 4,303,381 4,255,906 Equipment financing 1,350,579 1,314,311 Warehouse lending 647,767 643,754 Residential 1,313,785 1,281,637 Home equity 132,758 122,553 Other consumer 12,559 12,525 Total loans and leases $ 20,816,348 20,498,706 Deferred tax assets, net (59,716) Premises and equipment (1) 264,421 Other intangible assets 210,100 Bank-owned life insurance policies 645,510 Accrued interest receivable and other assets 986,729 Total assets acquired $ 27,663,853 Liabilities: Non-interest-bearing deposits $ 6,620,248 Interest-bearing deposits 16,643,755 Securities sold under agreements to repurchase and other borrowings 27,184 Long-term debt 516,881 Accrued expenses and other liabilities (1) 589,689 Total liabilities assumed $ 24,397,757 Net assets acquired 3,266,096 Goodwill $ 1,914,204 (1) Includes $100.0 million of ROU lease assets operating lease liabilities In connection with the merger with Sterling, the Company recorded $1.9 billion of goodwill, which represents the excess of the purchase price over the fair value of the net assets acquired. Information regarding the allocation of goodwill to the Company's reportable segments, as well as the carrying amounts and amortization of the core deposit intangible asset and customer relationship intangible assets, can be found within Note 21: Segment Reporting and Note 8: Goodwill and Other Intangible Assets, respectively. The following is a description of the valuation methodologies used to estimate the fair values of the significant assets acquired and liabilities assumed: Cash and due from banks and Interest-bearing deposits. The carrying amount of these assets is a reasonable estimate of fair value based on the short-term nature of these assets. Investment securities available-for-sale. The fair values for investment securities available-for-sale were based on quoted market prices, where available. If quoted market prices were not available, fair value estimates were based on observable inputs, including quoted market prices for similar instruments. Investment securities held-to-maturity were classified as investment securities available-for-sale based on the Company's intent at closing. Loans and leases. The fair values for loans and leases were estimated using a discounted cash flow methodology that considered factors including the type of loan or lease and the related collateral, classification status, fixed or variable interest rate, remaining term, amortization status, and current discount rates. In addition, the PD, LGD, and prepayment assumptions that were derived based on loan and lease characteristics, historical loss experience, comparable market data, and current and forecasted economic conditions were used to estimate expected credit losses. Loans and leases generally were valued individually. The discount rates used for loans and leases were based on current market rates for new originations or comparable loans and leases and include adjustments for liquidity. The discount rate did not include credit losses as that was included as a reduction to the estimated cash flows. Premises and equipment. The fair values for land and buildings were based on appraised values using the cost approach, which estimates the price a buyer would pay if they were to rebuild or reconstruct a similar property on a comparable piece of land. Intangible assets. A core deposit intangible asset represents the value of relationships with deposit clients. The fair value of the core deposit intangible asset was estimated using a net cost savings method, a form of discounted cash flow methodology that gave appropriate consideration to expected client attrition rates and other applicable adjustments to the projected deposit balance, the interest cost and net maintenance cost associated with the client deposit base, alternative cost of funds, and a discount rate used to discount the future economic benefits of the core deposit intangible asset to present value. The core deposit intangible asset is being amortized on an accelerated basis over 10 years based upon the period over which the estimated economic benefits are estimated to be received. Customer relationship intangible assets for payroll finance, factoring receivables finance, and wealth businesses were estimated using a discounted cash flow methodology that reflects the estimated value of the future net earnings for each relationship with adjustments for attrition. The customer relationship intangible assets are being amortized on an accelerated basis over their estimated useful life of 10 years. Bank-owned life insurance policies. The cash surrender value of these insurance policies is a reasonable estimate of fair value since it reflects the amount that would be realized by the contract owner upon discontinuance or surrender. Deposits. The fair values used for the demand and savings deposits by definition equal the amount payable on demand at the merger date. The fair values for time deposits were estimated using a discounted cash flow methodology that applies interest rates currently being offered to the contractual interest rates on such time deposits. Securities sold under agreements to repurchase and other borrowings. The carrying amount of these liabilities is a reasonable estimate of fair value based on the short-term nature of these liabilities. Long-term debt. The fair values of long-term debt instruments were estimated based on quoted market prices for the instrument, if available, or for similar instruments, if not available, or by using a discounted cash flow methodology based on current incremental borrowing rates for similar types of instruments. PCD Loans and Leases Purchased loans and leases that have experienced more-than-insignificant deterioration in credit quality since origination are considered PCD. For PCD loans and leases, the initial estimate of expected credit losses was recognized as an adjustment to the unpaid principal balance and non-credit discount at acquisition. Subsequent to the merger effective date, the Company recorded an ACL for non-PCD loans and leases of $175.1 million through an increase to the Provision for credit losses. There was no carryover of Sterling's previously recorded ACL on loans and leases. The following table reconciles the unpaid principal balance to the fair value of PCD loans and leases by portfolio segment: (In thousands) Commercial Consumer Total Unpaid principal balance $ 3,394,963 $ 541,471 $ 3,936,434 ACL at acquisition (115,464) (20,852) (136,316) Non-credit (discount) (40,947) (2,784) (43,731) Fair value $ 3,238,552 $ 517,835 $ 3,756,387 Supplemental Pro Forma Financial Information (Unaudited) The following table summarizes supplemental pro forma financial information giving effect to the merger as if it had been completed on January 1, 2021: Years ended December 31, (In thousands) 2022 2021 Net interest income $ 1,961,005 $ 1,802,862 Non-interest income 440,783 487,301 Net income 869,639 574,927 The supplemental pro forma financial information does not necessarily reflect the results of operations that would have occurred had the Company merged with Sterling on January 1, 2021. The supplemental pro forma financial information includes the impact of (i) accreting and amortizing the discounts and premiums associated with the estimated fair value adjustments to acquired loans and leases, investment securities, deposits, and long-term debt, (ii) the amortization of recognized intangible assets, (iii) the elimination of Sterling's historical accretion and amortization of discounts and premiums and deferred origination fees and costs on loans and leases, (iv) the elimination of Sterling's historical accretion and amortization of discounts and premiums on investment securities, and (v) the related estimated income tax effects. Cost savings and other business synergies related to the merger are not included in the supplemental pro forma financial information. In addition, the supplemental pro forma financial information was adjusted for merger-related expenses, as follows: Years ended December 31, (In thousands) 2022 2021 Compensation and benefits (1) $ 79,001 $ 13,987 Occupancy (2) 36,586 256 Technology and equipment (3) 24,688 290 Marketing 416 — Professional and outside services (4) 73,070 22,273 Other expense (5) 32,700 648 Total merger-related expenses $ 246,461 $ 37,454 (1) Comprised primarily of employee severance and retention costs, and executive restricted stock awards. (2) Comprised primarily of charges associated with the Company’s 2022 corporate real estate consolidation plan. (3) Comprised primarily of technology contract termination costs. (4) Comprised primarily of advisory, legal, accounting, and other professional fees. (5) Comprised primarily of disposals on property and equipment, contract termination costs, and other miscellaneous expenses. The Company's operating results for the years ended December 31, 2023, and 2022, include the operating results of acquired assets and assumed liabilities of Sterling subsequent to the merger on January 31, 2022. Due to the various conversions of Sterling systems during the years ended December 31, 2023, and 2022, as well as other streamlining and integration of operating activities into those of the Company, historical reporting for the former Sterling operations after January 31, 2022, is impracticable, and thus disclosures of Sterling's revenue and earnings since the merger effective date that are included in the accompanying Consolidated Statements of Income for the reporting period is impracticable. Bend Acquisition On February 18, 2022, the Company acquired 100% of the equity interests of Bend, a cloud-based platform solution provider for HSAs, in exchange for cash of $55.3 million. The acquisition accelerated the Company's efforts underway to deliver enhanced user experiences at HSA Bank. The transaction was accounted for as a business combination, and resulted in the addition of $19.6 million in net assets, which primarily comprised $15.9 million of internal use software and a $3.0 million customer relationship intangible asset. The Company's valuations of the assets acquired and liabilities assumed in the Bend acquisition were considered final as of March 31, 2023. Inland Bank and Trust HSA Portfolio Acquisition On November 7, 2022, the Company acquired a portfolio of HSAs from Inland Bank and Trust. The transaction was accounted for as an asset acquisition, and the Company received $15.6 million in both cash and deposits on the acquisition date. The Company also paid a 2.00% deposit premium based on the final settlement of deposits, which resulted in the recognition of a $0.3 million core deposit intangible asset. The accounts and associated deposits obtained from this transaction provided stable funding for future loan growth and increased the Company's revenues. interLINK Acquisition On January 11, 2023, the Company acquired 100% ownership of interLINK from StoneCastle Partners LLC. interLINK is a technology-enabled deposit management platform that administers over $9 billion of deposits from FDIC-insured cash sweep programs between banks and broker/dealers and clearing firms. The acquisition provided the Company with access to a unique source of core deposit funding and scalable liquidity and added another technology-enabled channel to its already differentiated, omnichannel deposit gathering capabilities. The total purchase price of the acquisition was $174.6 million, which included cash paid of $158.6 million and $16.0 million of contingent consideration measured at fair value. The contingent consideration is payable in cash upon the achievement of discrete customer and deposit growth events within three years of the acquisition date. Additional information regarding the determination of fair value for contingent consideration liabilities can be found within Note 18: Fair Value Measurements. The transaction was accounted for as a business combination, and resulted in the addition of $31.4 million in net assets measured at fair value, which primarily comprised $36.0 million of broker dealer relationship intangible assets, $6.0 million of developed technology, a $4.0 million non-competition agreement intangible asset, and $15.9 million of royalty liabilities. The $143.2 million of goodwill recognized is deductible for tax purposes. The Company's valuations of the assets acquired and liabilities assumed in the interLINK acquisition were considered final as of June 30, 2023. Exit Activities The following table summarizes the change in Accrued expenses and other liabilities as it relates to severance and contract termination costs, which were primarily incurred in connection with the Sterling merger: Years ended December 31, 2023 2022 (In thousands) Severance Contract Termination (1) Total Severance (2) Contract Termination Total Balance, beginning of period $ 7,583 $ 30,362 $ 37,945 $ 10,835 $ — $ 10,835 Additions charged to expense 18,069 14,000 32,069 36,092 34,152 70,244 Cash payments (14,247) (30,551) (44,798) (35,014) (3,790) (38,804) Other (1,300) (6,587) (7,887) (4,330) — (4,330) Balance, end of period $ 10,105 $ 7,224 $ 17,329 $ 7,583 $ 30,362 $ 37,945 (1) Other contract termination includes (i) a reduction of $4.8 million to a previously recorded technology-related contract termination charge recorded in Technology and equipment expense due to a change in the expected use of certain services after core conversion in 2023, and (ii) a reduction of $1.7 million to a previously recorded contract termination charge recorded in Other expense due to a decrease in volume usage in 2023. (2) Other severance reflects the release of $4.1 million from the Company's severance accrual in 2022, as the Company re-evaluated its strategic priorities as a combined organization in connection with the Sterling merger, which resulted in modifications to the Company's strategic initiatives that were announced in December 2020.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities Available-for-Sale The following table summarizes the amortized cost and fair value of available-for-sale securities by major type: At December 31, 2023 (In thousands) Amortized Cost (1) Unrealized Unrealized Losses Fair Value Government agency debentures $ 302,212 $ — $ (37,579) $ 264,633 Municipal bonds and notes 1,626,126 8 (52,901) 1,573,233 Agency CMO 52,994 — (4,053) 48,941 Agency MBS 3,568,140 32,461 (253,503) 3,347,098 Agency CMBS 2,569,438 18,204 (299,571) 2,288,071 CMBS 788,478 — (24,729) 763,749 Corporate debt 704,569 — (82,414) 622,155 Private label MBS 46,635 — (3,827) 42,808 Other 9,830 — (789) 9,041 Total available-for-sale $ 9,668,422 $ 50,673 $ (759,366) $ 8,959,729 At December 31, 2022 (In thousands) Amortized Cost (1) Unrealized Unrealized Losses Fair Value U.S. Treasury notes $ 755,968 $ — $ (38,928) $ 717,040 Government agency debentures 302,018 — (43,644) 258,374 Municipal bonds and notes 1,719,110 5 (85,913) 1,633,202 Agency CMO 64,984 — (5,019) 59,965 Agency MBS 2,461,337 26 (303,339) 2,158,024 Agency CMBS 1,664,600 — (258,114) 1,406,486 CMBS 929,588 — (32,948) 896,640 CLO 2,108 — (1) 2,107 Corporate debt 795,999 — (91,587) 704,412 Private label MBS 48,895 — (4,646) 44,249 Other 12,548 — (350) 12,198 Total available-for-sale $ 8,757,155 $ 31 $ (864,489) $ 7,892,697 (1) Accrued interest receivable on available-for-sale securities of $42.5 million and $36.9 million at December 31, 2023, and 2022, respectively, is excluded from amortized cost and is included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. Unrealized Losses The following tables summarize the gross unrealized losses and fair value of available-for-sale securities by length of time each major security type has been in a continuous unrealized loss position: At December 31, 2023 Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Unrealized Fair Unrealized Number of Fair Unrealized Government agency debentures $ — $ — $ 264,633 $ (37,579) 19 $ 264,633 $ (37,579) Municipal bonds and notes 18,066 (124) 1,536,656 (52,777) 386 1,554,722 (52,901) Agency CMO — — 48,941 (4,053) 36 48,941 (4,053) Agency MBS 71,187 (272) 1,945,221 (253,231) 457 2,016,408 (253,503) Agency CMBS 430,070 (16,137) 1,314,681 (283,434) 145 1,744,751 (299,571) CMBS 43,844 (856) 719,905 (23,873) 42 763,749 (24,729) Corporate debt 4,278 (27) 617,877 (82,387) 91 622,155 (82,414) Private label MBS — — 42,808 (3,827) 3 42,808 (3,827) Other — — 9,041 (789) 2 9,041 (789) Total $ 567,445 $ (17,416) $ 6,499,763 $ (741,950) 1,181 $ 7,067,208 $ (759,366) At December 31, 2022 Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Unrealized Fair Unrealized Number of Fair Unrealized U.S. Treasury notes $ 337,563 $ (19,167) $ 379,477 $ (19,761) 23 $ 717,040 $ (38,928) Government agency debentures 258,374 (43,644) — — 19 258,374 (43,644) Municipal bonds and notes 1,616,771 (85,913) — — 444 1,616,771 (85,913) Agency CMO 55,693 (4,640) 4,272 (379) 39 59,965 (5,019) Agency MBS 1,641,544 (206,412) 515,206 (96,927) 460 2,156,750 (303,339) Agency CMBS 485,333 (68,674) 921,153 (189,440) 132 1,406,486 (258,114) CMBS 273,150 (8,982) 598,490 (23,966) 52 871,640 (32,948) CLO — — 2,107 (1) 1 2,107 (1) Corporate debt 692,990 (89,692) 8,421 (1,895) 105 701,411 (91,587) Private label MBS 44,249 (4,646) — — 3 44,249 (4,646) Other 12,198 (350) — — 4 12,198 (350) Total $ 5,417,865 $ (532,120) $ 2,429,126 $ (332,369) 1,282 $ 7,846,991 $ (864,489) The $105.1 million decrease in gross unrealized losses from December 31, 2022, to December 31, 2023, is primarily due to lower long-term market rates. The Company assesses each available-for-sale security that is in an unrealized loss position to determine whether the decline in fair value below the amortized cost basis is a result from a credit loss or other factors. At both December 31, 2023, and 2022, no ACL was recorded on available-for-sale securities as each of the securities in the Company's portfolio are investment grade, current as to principal and interest, and their price changes are consistent with interest and credit spreads when adjusting for convexity, rating, and industry differences. As of December 31, 2023, based on current market conditions and the Company's targeted balance sheet composition strategy, the Company intends to hold its available-for-sale securities with unrealized loss positions through the anticipated recovery period. The issuers of these available-for-sale securities have not, to the Company’s knowledge, established any cause for default. Market prices are expected to approach par as the securities approach maturity. Contractual Maturities The following table summarizes the amortized cost and fair value of available-for-sale securities by contractual maturity: At December 31, 2023 (In thousands) Amortized Cost Fair Value Maturing within 1 year $ 37,908 $ 36,958 After 1 year through 5 years 644,959 616,176 After 5 years through 10 years 1,363,257 1,263,900 After 10 years 7,622,298 7,042,695 Total available-for-sale $ 9,668,422 $ 8,959,729 Available-for-sale securities that are not due at a single maturity date have been categorized based on the maturity date of the underlying collateral. Actual principal cash flows may differ from this categorization as borrowers have the right to prepay their obligations with or without prepayment penalties. Sales of Available-for Sale Securities During the year ended December 31, 2023, the Company sold U.S. Treasury notes, Corporate debt securities, and Municipal bonds and notes classified as available-for-sale for proceeds of $789.6 million, which resulted in gross realized losses of $37.4 million. Because $3.8 million of the total loss recognized for the year ended December 31, 2023, was attributed to a decline in credit quality, this portion of the charge has been included in the Provision for credit losses on the accompanying Consolidated Statements of Income. During the year ended December 31, 2022, the Company sold Municipal bonds and notes classified as available-for-sale for proceeds of $172.9 million, which resulted in gross realized losses of $6.8 million. There were no sales of available-for-sales securities during the year ended December 31, 2021. Other Information The following table summarizes the carrying value of available-for-sale securities pledged for deposits, borrowings, and other purposes: At December 31, (In thousands) 2023 2022 Pledged for deposits $ 2,102,115 $ 2,573,072 Pledged for borrowings and other 6,111,430 1,195,101 Total available-for-sale securities pledged $ 8,213,545 $ 3,768,173 At December 31, 2023, the Company had callable available-for-sale securities with an aggregate carrying value of $3.0 billion. Held-to-Maturity The following table summarizes the amortized cost, fair value, and ACL on held-to-maturity securities by major type: At December 31, 2023 (In thousands) Amortized Cost (1) Unrealized Gains Unrealized Losses Fair Value Allowance Net Carrying Value Agency CMO $ 23,470 $ — $ (1,728) $ 21,742 $ — $ 23,470 Agency MBS 2,409,521 1,141 (284,776) 2,125,886 — 2,409,521 Agency CMBS 3,625,627 18,586 (514,534) 3,129,679 — 3,625,627 Municipal bonds and notes 916,104 2,440 (24,877) 893,667 209 915,895 CMBS 100,075 — (6,426) 93,649 — 100,075 Total held-to-maturity $ 7,074,797 $ 22,167 $ (832,341) $ 6,264,623 $ 209 $ 7,074,588 At December 31, 2022 (In thousands) Amortized Cost (1) Unrealized Gains Unrealized Losses Fair Value Allowance Net Carrying Value Agency CMO $ 28,358 $ — $ (2,060) $ 26,298 $ — $ 28,358 Agency MBS 2,626,114 827 (339,592) 2,287,349 — 2,626,114 Agency CMBS 2,831,949 845 (407,648) 2,425,146 — 2,831,949 Municipal bonds and notes 928,845 1,098 (47,183) 882,760 182 928,663 CMBS 149,613 — (9,713) 139,900 — 149,613 Total held-to-maturity $ 6,564,879 $ 2,770 $ (806,196) $ 5,761,453 $ 182 $ 6,564,697 (1) Accrued interest receivable on held-to-maturity securities of $24.9 million and $24.2 million at December 31, 2023, and 2022, respectively, is excluded from amortized cost and is included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. An ACL on held-to-maturity securities is recorded for certain Municipal bonds and notes to account for expected lifetime credit losses. Agency securities represent obligations issued by a U.S. government-sponsored enterprise or other federally-related entity and are either explicitly or implicitly guaranteed, and therefore, assumed to be zero loss. Held-to-maturity securities with gross unrealized losses and no ACL are considered to be high credit quality, and therefore, zero credit loss has been recorded. The following table summarizes the activity in the ACL on held-to-maturity securities: Years ended December 31, (In thousands) 2023 2022 2021 Balance, beginning of period $ 182 $ 214 $ 299 Provision (benefit) for credit losses 27 (32) (85) Balance, end of period $ 209 $ 182 $ 214 Contractual Maturities The following table summarizes the amortized cost and fair value of held-to-maturity securities by contractual maturity: At December 31, 2023 (In thousands) Amortized Cost Fair Value Maturing within 1 year $ 8,122 $ 8,136 After 1 year through 5 years 59,932 60,434 After 5 years through 10 years 363,498 349,083 After 10 years 6,643,245 5,846,970 Total held-to-maturity $ 7,074,797 $ 6,264,623 Held-to-maturity securities that are not due at a single maturity date have been categorized based on the maturity date of the underlying collateral. Actual principal cash flows may differ from this categorization as borrowers have the right to prepay their obligations with or without prepayment penalties. Credit Quality Information The Company monitors the credit quality of held-to-maturity securities through credit ratings provided by Standard & Poor's Rating Services, Moody's, Fitch Ratings, Inc., Kroll Bond Rating Agency, or DBRS Inc. Credit ratings express opinions about the credit quality of a security and are updated at each quarter end. Investment grade securities are rated BBB- or higher by S&P, or Baa3 or higher by Moody's, and are generally considered by the rating agencies and market participants to be of low credit risk. Conversely, securities rated below investment grade, which are labeled as speculative grade by the rating agencies, are considered to have distinctively higher credit risk than investment grade securities. There were no speculative grade held-to-maturity securities at December 31, 2023, or December 31, 2022. Held-to-maturity securities that are not rated are collateralized with U.S. Treasury obligations. The following tables summarize the amortized cost of held-to-maturity securities based on their lowest publicly available credit rating: At December 31, 2023 Investment Grade (In thousands) Aaa Aa1 Aa2 Aa3 A1 A2 A3 Not Rated Agency CMOs $ — $ 23,470 $ — $ — $ — $ — $ — $ — Agency MBS — 2,409,521 — — — — — — Agency CMBS — 3,625,627 — — — — — — Municipal bonds and notes 333,479 162,615 253,671 115,404 32,732 — 4,165 14,038 CMBS 100,075 — — — — — — — Total held-to-maturity $ 433,554 $ 6,221,233 $ 253,671 $ 115,404 $ 32,732 $ — $ 4,165 $ 14,038 At December 31, 2022 Investment Grade (In thousands) Aaa Aa1 Aa2 Aa3 A1 A2 A3 Not Rated Agency CMOs $ — $ 28,358 $ — $ — $ — $ — $ — $ — Agency MBS — 2,626,114 — — — — — — Agency CMBS — 2,831,949 — — — — — — Municipal bonds and notes 336,035 163,312 255,235 116,870 38,177 4,165 — 15,051 CMBS 149,613 — — — — — — — Total held-to-maturity $ 485,648 $ 5,649,733 $ 255,235 $ 116,870 $ 38,177 $ 4,165 $ — $ 15,051 At December 31, 2023, and 2022, there were no held-to-maturity debt securities past due under the terms of their agreements or in non-accrual status. Other Information The following table summarizes the carrying value of held-to-maturity securities pledged for deposits, borrowings, and other purposes: At December 31, (In thousands) 2023 2022 Pledged for deposits $ 1,212,824 $ 1,596,777 Pledged for borrowings and other 5,582,379 260,735 Total held-to-maturity securities pledged $ 6,795,203 $ 1,857,512 At December 31, 2023, the Company had callable held-to-maturity securities with an aggregate carrying value of $0.9 billion.

Loans and Leases

Loans and Leases	12 Months Ended
	Dec. 31, 2023
Loans and Leases Receivable Disclosure [Abstract]
Loans and Leases	Loans and Leases The following table summarizes loans and leases by portfolio segment and class: At December 31, (In thousands) 2023 2022 Commercial non-mortgage $ 16,885,475 $ 16,392,795 Asset-based 1,557,841 1,821,642 Commercial real estate 13,569,762 12,997,163 Multi-family 7,587,970 6,621,982 Equipment financing 1,328,786 1,628,393 Warehouse lending — 641,976 Commercial portfolio 40,929,834 40,103,951 Residential 8,227,923 7,963,420 Home equity 1,516,955 1,633,107 Other consumer 51,340 63,948 Consumer portfolio 9,796,218 9,660,475 Loans and leases $ 50,726,052 $ 49,764,426 The carrying amount of loans and leases at December 31, 2023, and 2022, includes net unamortized (discounts)/premiums and net unamortized deferred (fees)/costs totaling $(33.8) million and $(68.7) million, respectively. Accrued interest receivable of $270.4 million and $226.3 million at December 31, 2023, and 2022, respectively, is excluded from the carrying amount of loans and leases and is included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. At December 31, 2023, the Company had pledged $16.6 billion of eligible loans as collateral to support borrowing capacity at the FHLB. Non-Accrual and Past Due Loans and Leases The following tables summarize the aging of accrual and non-accrual loans and leases by class: At December 31, 2023 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Current Total Loans Commercial non-mortgage $ 2,270 $ 890 $ 94 $ 122,855 $ 126,109 $ 16,759,366 $ 16,885,475 Asset-based — — — 35,068 35,068 1,522,773 1,557,841 Commercial real estate 1,459 — 184 11,383 13,026 13,556,736 13,569,762 Multi-family 5,198 2,340 — — 7,538 7,580,432 7,587,970 Equipment financing 3,966 8 — 9,828 13,802 1,314,984 1,328,786 Commercial portfolio 12,893 3,238 278 179,134 195,543 40,734,291 40,929,834 Residential 14,894 6,218 — 5,704 26,816 8,201,107 8,227,923 Home equity 5,676 3,285 — 23,545 32,506 1,484,449 1,516,955 Other consumer 410 94 — 142 646 50,694 51,340 Consumer portfolio 20,980 9,597 — 29,391 59,968 9,736,250 9,796,218 Total $ 33,873 $ 12,835 $ 278 $ 208,525 $ 255,511 $ 50,470,541 $ 50,726,052 At December 31, 2022 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Current (1) Total Loans Commercial non-mortgage $ 8,434 $ 821 $ 645 $ 71,884 $ 81,784 $ 16,311,011 $ 16,392,795 Asset-based 5,921 — — 20,024 25,945 1,795,697 1,821,642 Commercial real estate 1,494 23,492 68 39,057 64,111 12,933,052 12,997,163 Multi-family 1,157 — — 636 1,793 6,620,189 6,621,982 Equipment financing 806 9,988 — 12,344 23,138 1,605,255 1,628,393 Warehouse Lending — — — — — 641,976 641,976 Commercial portfolio 17,812 34,301 713 143,945 196,771 39,907,180 40,103,951 Residential 8,246 3,083 — 25,424 36,753 7,926,667 7,963,420 Home equity 5,293 2,820 — 27,924 36,037 1,597,070 1,633,107 Other consumer 1,028 85 13 148 1,274 62,674 63,948 Consumer portfolio 14,567 5,988 13 53,496 74,064 9,586,411 9,660,475 Total $ 32,379 $ 40,289 $ 726 $ 197,441 $ 270,835 $ 49,493,591 $ 49,764,426 (1) At December 31, 2022, there were $28.5 million of commercial loans that had reached their contractual maturity but were actively in the process of being refinanced with the Company. Due to the status of the refinancing, these commercial loans have been reported as current in the table above. The following table provides additional information on non-accrual loans and leases: At December 31, 2023 2022 (In thousands) Non-accrual Non-accrual With No Allowance Non-accrual Non-accrual With No Allowance Commercial non-mortgage $ 122,855 $ 20,066 $ 71,884 $ 12,598 Asset-based 35,068 1,330 20,024 1,491 Commercial real estate 11,383 2,681 39,057 90 Multi-family — — 636 — Equipment financing 9,828 1,584 12,344 2,240 Commercial portfolio 179,134 25,661 143,945 16,419 Residential 5,704 856 25,424 10,442 Home equity 23,545 12,471 27,924 15,193 Other consumer 142 49 148 5 Consumer portfolio 29,391 13,376 53,496 25,640 Total $ 208,525 $ 39,037 $ 197,441 $ 42,059 Interest income on non-accrual loans and leases that would have been recognized had the loans and leases been current in accordance with their contractual terms totaled $22.9 million, $16.9 million, and $11.0 million for the years ended December 31, 2023, 2022, and 2021, respectively. Allowance for Credit Losses on Loans and Leases The following tables summarize the change in the ACL on loans and leases by portfolio segment: At or for the Years ended December 31, 2023 2022 2021 (In thousands) Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total ACL on loans and leases: Balance, beginning of period $ 533,125 $ 61,616 $ 594,741 $ 257,877 $ 43,310 $ 301,187 $ 312,244 $ 47,187 $ 359,431 Adoption of ASU No. 2022-02 7,704 (1,831) 5,873 — — — — — — Initial allowance for PCD loans and leases (1) — — — 78,376 9,669 88,045 — — — Provision (benefit) 138,057 5,152 143,209 268,295 4,502 272,797 (48,651) (5,764) (54,415) Charge-offs (104,509) (12,703) (117,212) (82,860) (4,662) (87,522) (9,437) (9,217) (18,654) Recoveries 3,286 5,840 9,126 11,437 8,797 20,234 3,721 11,104 14,825 Balance, end of period $ 577,663 $ 58,074 $ 635,737 $ 533,125 $ 61,616 $ 594,741 $ 257,877 $ 43,310 $ 301,187 Individually evaluated for credit losses 43,559 4,635 48,194 34,793 12,441 47,234 16,965 4,108 21,073 Collectively evaluated for credit losses $ 534,104 $ 53,439 $ 587,543 $ 498,332 $ 49,175 $ 547,507 $ 240,912 $ 39,202 $ 280,114 (1) Represents the establishment of the initial reserve for PCD loans and leases, which is reported net of $48.3 million of day one charge-offs recognized at the date of acquisition in accordance with GAAP. Credit Quality Indicators To measure credit risk for the commercial portfolio, the Company employs a dual grade credit risk grading system for estimating the PD and LGD. The credit risk grade system assigns a rating to each borrower and to the facility, which together form a Composite Credit Risk Profile. The credit risk grade system categorizes borrowers by common financial characteristics that measure the credit strength of borrowers and facilities by common structural characteristics. The Composite Credit Risk Profile has ten grades, with each grade corresponding to a progressively greater risk of loss. Grades (1) to (6) are considered pass ratings, and grades (7) to (10) are considered criticized, as defined by the regulatory agencies. A (7) "Special Mention" rating has a potential weakness that, if left uncorrected, may result in deterioration of the repayment prospects for the asset. An (8) "Substandard" rating has a well-defined weakness that jeopardizes the full repayment of the debt. A (9) "Doubtful" rating has all of the same weaknesses as a substandard asset with the added characteristic that the weakness makes collection or liquidation in full given current facts, conditions, and values improbable. Assets classified as a (10) "Loss" rating are considered uncollectible and charged-off. Risk ratings, which are assigned to differentiate risk within the portfolio, are reviewed on an ongoing basis and revised to reflect changes in a borrower's current financial position and outlook, risk profile, and the related collateral and structural position. Loan officers review updated financial information or other loan factors on at least an annual basis for all pass rated loans to assess the accuracy of the risk grade. Criticized loans undergo more frequent reviews and enhanced monitoring. To measure credit risk for the consumer portfolio, the most relevant credit characteristic is the FICO score, which is a widely used credit scoring system that ranges from 300 to 850. A lower FICO score is indicative of higher credit risk and a higher FICO score is indicative of lower credit risk. FICO scores are updated at least on a quarterly basis. The factors such as past due status, employment status, collateral, geography, loans discharged in bankruptcy, and the status of first lien position loans on second lien position loans, are also considered to be consumer portfolio credit quality indicators. For portfolio monitoring purposes, the Company estimates the current value of property secured as collateral for home equity and residential first mortgage lending products on an ongoing basis. The estimate is based on home price indices compiled by the S&P/Case-Shiller Home Price Indices. Real estate price data is applied to the loan portfolios taking into account the age of the most recent valuation and geographic area. The following tables summarize the amortized cost basis of commercial loans and leases by Composite Credit Risk Profile grade and origination year: At December 31, 2023 (In thousands) 2023 2022 2021 2020 2019 Prior Revolving Loans Amortized Cost Basis Total Commercial non-mortgage: Risk rating: Pass $ 2,602,444 $ 4,089,327 $ 1,371,139 $ 711,362 $ 610,199 $ 952,097 $ 5,970,588 $ 16,307,156 Special mention 15,184 60,240 61,235 33,111 — 720 48,561 219,051 Substandard 48,849 104,087 23,258 28,222 44,612 30,426 79,778 359,232 Doubtful — 8 — — 3 25 — 36 Total commercial non-mortgage 2,666,477 4,253,662 1,455,632 772,695 654,814 983,268 6,098,927 16,885,475 Current period gross write-offs 325 7,637 1,775 512 969 4,391 — 15,609 Asset-based: Risk rating: Pass 23,007 — — — 3,280 34,999 1,333,271 1,394,557 Special mention 651 763 — — 3,676 — 29,610 34,700 Substandard — — — — 1,330 — 127,254 128,584 Total asset-based 23,658 763 — — 8,286 34,999 1,490,135 1,557,841 Current period gross write-offs — — — — 13,189 3,900 — 17,089 Commercial real estate: Risk rating: Pass 2,265,428 3,502,425 1,831,005 1,195,732 1,193,642 3,112,770 176,668 13,277,670 Special mention 850 4,675 14,463 31,405 23,443 37,688 1,210 113,734 Substandard 25,802 16,179 9,545 15,418 58,602 52,812 — 178,358 Total commercial real estate 2,292,080 3,523,279 1,855,013 1,242,555 1,275,687 3,203,270 177,878 13,569,762 Current period gross write-offs 4,632 — 12,617 3,813 2,754 38,569 — 62,385 Multi-family: Risk rating: Pass 1,597,599 1,934,100 1,041,416 442,888 595,676 1,920,618 — 7,532,297 Special mention — — — — 260 35,942 — 36,202 Substandard — — — 364 11,563 7,544 — 19,471 Total multi-family 1,597,599 1,934,100 1,041,416 443,252 607,499 1,964,104 — 7,587,970 Current period gross write-offs — — — — — 3,447 — 3,447 Equipment financing: Risk rating: Pass 335,874 297,186 232,304 176,061 183,679 69,927 — 1,295,031 Special mention — — 116 — 90 — — 206 Substandard — 9,144 8,064 6,600 4,285 5,456 — 33,549 Total equipment financing 335,874 306,330 240,484 182,661 188,054 75,383 — 1,328,786 Current period gross write-offs — — — 2,633 3,304 42 — 5,979 Total commercial portfolio $ 6,915,688 $ 10,018,134 $ 4,592,545 $ 2,641,163 $ 2,734,340 $ 6,261,024 $ 7,766,940 $ 40,929,834 Current period gross write-offs $ 4,957 $ 7,637 $ 14,392 $ 6,958 $ 20,216 $ 50,349 $ — $ 104,509 At December 31, 2022 (In thousands) 2022 2021 2020 2019 2018 Prior Revolving Loans Amortized Cost Basis Total Commercial non-mortgage: Pass $ 5,154,781 $ 1,952,158 $ 965,975 $ 792,977 $ 593,460 $ 780,200 $ 5,670,532 $ 15,910,083 Special mention 104,277 15,598 21,168 263 14,370 7,770 40,142 203,588 Substandard 28,203 11,704 69,954 36,604 70,634 16,852 41,917 275,868 Doubtful — — — 1 — — 3,255 3,256 Total commercial non-mortgage 5,287,261 1,979,460 1,057,097 829,845 678,464 804,822 5,755,846 16,392,795 Asset-based: Pass 19,659 3,901 9,424 14,413 5,163 55,553 1,551,250 1,659,363 Special mention — — — — — — 80,476 80,476 Substandard — — — 1,491 — — 80,312 81,803 Total asset-based 19,659 3,901 9,424 15,904 5,163 55,553 1,712,038 1,821,642 Commercial real estate: Pass 3,420,635 2,246,672 1,556,185 1,605,869 1,058,730 2,681,052 97,832 12,666,975 Special mention 21,878 8,995 7,264 37,570 47,419 66,652 1,000 190,778 Substandard 519 2,459 216 31,163 47,021 57,997 — 139,375 Doubtful — — — 1 — 34 — 35 Total commercial real estate 3,443,032 2,258,126 1,563,665 1,674,603 1,153,170 2,805,735 98,832 12,997,163 Multi-family: Pass 1,992,980 1,057,705 507,065 694,066 444,564 1,748,337 51,655 6,496,372 Special mention 37,677 — — 95 40,307 726 8,838 87,643 Substandard — — 382 — 12,681 24,904 — 37,967 Total multi-family 2,030,657 1,057,705 507,447 694,161 497,552 1,773,967 60,493 6,621,982 Equipment financing: Pass 388,641 345,792 331,419 308,441 98,874 83,264 — 1,556,431 Special mention — 185 — 11,965 6,775 25 — 18,950 Substandard 314 16,711 18,436 5,016 5,307 7,228 — 53,012 Total equipment financing 388,955 362,688 349,855 325,422 110,956 90,517 — 1,628,393 Warehouse lending: Pass — — — — — — 641,976 641,976 Total warehouse lending — — — — — — 641,976 641,976 Total commercial portfolio $ 11,169,564 $ 5,661,880 $ 3,487,488 $ 3,539,935 $ 2,445,305 $ 5,530,594 $ 8,269,185 $ 40,103,951 The following tables summarize the amortized cost basis of consumer loans by FICO score and origination year: At December 31, 2023 (In thousands) 2023 2022 2021 2020 2019 Prior Revolving Loans Amortized Cost Basis Total Residential: Risk rating: 800+ $ 214,446 $ 847,009 $ 1,096,109 $ 451,307 $ 141,919 $ 910,117 $ — $ 3,660,907 740-799 363,696 703,568 755,750 279,946 112,303 633,578 — 2,848,841 670-739 137,460 293,699 292,255 95,838 48,412 346,663 — 1,214,327 580-669 20,208 52,962 45,770 14,840 10,492 106,497 — 250,769 579 and below 6,909 52,690 11,749 1,345 128,714 51,672 — 253,079 Total residential 742,719 1,949,928 2,201,633 843,276 441,840 2,048,527 — 8,227,923 Current period gross write-offs — — 387 — 153 4,630 — 5,170 Home equity: Risk rating: 800+ 27,047 27,439 35,927 25,586 8,110 56,062 391,616 571,787 740-799 24,772 20,069 27,147 13,888 5,158 34,190 355,926 481,150 670-739 15,857 15,655 15,389 5,992 3,189 29,454 242,189 327,725 580-669 3,080 3,786 1,991 1,658 1,115 9,988 70,102 91,720 579 and below 696 1,109 1,079 576 552 6,319 34,242 44,573 Total home equity 71,452 68,058 81,533 47,700 18,124 136,013 1,094,075 1,516,955 Current period gross write-offs — 4 81 — 104 3,114 — 3,303 Other consumer: Risk rating: 800+ 432 356 1,913 189 255 77 25,699 28,921 740-799 1,318 586 486 730 690 381 7,180 11,371 670-739 526 570 358 981 1,210 79 3,549 7,273 580-669 69 169 129 153 303 56 1,983 2,862 579 and below 125 97 61 11 28 1 590 913 Total other consumer 2,470 1,778 2,947 2,064 2,486 594 39,001 51,340 Current period gross write-offs 3,263 7 2 218 377 363 — 4,230 Total consumer portfolio 816,641 2,019,764 2,286,113 893,040 462,450 2,185,134 1,133,076 9,796,218 Current period gross write-offs $ 3,263 $ 11 $ 470 $ 218 $ 634 $ 8,107 $ — $ 12,703 At December 31, 2022 (In thousands) 2022 2021 2020 2019 2018 Prior Revolving Loans Amortized Cost Basis Total Residential: 800+ $ 527,408 $ 954,568 $ 469,518 $ 160,596 $ 28,361 $ 997,409 $ — $ 3,137,860 740-799 963,026 946,339 311,295 111,913 43,684 689,771 — 3,066,028 670-739 381,515 350,671 103,999 62,365 18,451 384,687 — 1,301,688 580-669 40,959 49,648 14,484 5,836 2,357 138,107 — 251,391 579 and below 52,464 3,693 2,057 84,032 1,299 62,908 — 206,453 Total residential 1,965,372 2,304,919 901,353 424,742 94,152 2,272,882 — 7,963,420 Home equity: 800+ 25,475 35,129 25,612 7,578 12,545 55,352 465,318 627,009 740-799 26,743 35,178 17,621 8,111 7,765 32,270 398,692 526,380 670-739 18,396 16,679 8,175 3,635 7,614 30,060 259,646 344,205 580-669 2,848 3,068 1,520 1,456 1,163 13,607 76,614 100,276 579 and below 426 386 651 661 563 4,736 27,814 35,237 Total home equity 73,888 90,440 53,579 21,441 29,650 136,025 1,228,084 1,633,107 Other consumer: 800+ 495 218 544 1,045 247 56 19,196 21,801 740-799 888 2,624 1,959 2,494 941 364 12,218 21,488 670-739 977 603 2,480 4,238 1,041 118 6,107 15,564 580-669 211 117 337 801 173 54 2,223 3,916 579 and below 169 101 29 116 36 21 707 1,179 Total other consumer 2,740 3,663 5,349 8,694 2,438 613 40,451 63,948 Total consumer portfolio 2,042,000 2,399,022 960,281 454,877 126,240 2,409,520 1,268,535 9,660,475 Collateral Dependent Loans and Leases A non-accrual loan or lease is considered collateral dependent when the borrower is experiencing financial difficulty and when repayment is substantially expected to be provided through the operation or sale of collateral. Commercial non-mortgage loans, At December 31, 2023, and 2022, the carrying amount of collateral dependent loans was $66.1 million and $43.8 million, respectively, for commercial loans and leases, and $22.7 million and $45.2 million, respectively, for consumer loans. The ACL for collateral dependent loans and leases is individually assessed based on the fair value of the collateral less costs to sell at the reporting date. At December 31, 2023, and 2022, the collateral value associated with collateral dependent loans and leases was $93.7 million and $108.0 million, respectively. Modifications to Borrowers Experiencing Financial Difficulty On January 1, 2023, the Company adopted ASU 2022-02, which eliminated the accounting guidance for TDRs and enhanced the disclosure requirements for certain loan modifications when a borrower is experiencing financial difficulty. For a description of the Company's accounting policies related to the accounting and reporting of TDRs, for which comparative period information is presented, refer to Note 1: Summary of Significant Accounting Policies. In certain circumstances, the Company enters into agreements to modify the terms of loans to borrowers experiencing financial difficulty. A variety of solutions are offered to borrowers experiencing financial difficulty, including loan modifications that may result in principal forgiveness, interest rate reductions, payment delays, term extension, or a combination thereof. The following is a description of each of these types of modifications: • Principal forgiveness – The outstanding principal balance of a loan may be reduced by a specified amount. Principal forgiveness may occur voluntarily as part of a negotiated agreement with a borrower, or involuntarily through a bankruptcy proceeding. • Interest rate reductions – Includes modifications where the contractual interest rate of the loan has been reduced. • Payment delays – Deferral arrangements that allow borrowers to delay a scheduled loan payment to a later date. Deferred loan payments do not affect the original contracted maturity terms of the loan. Modifications that result in only an insignificant payment delay are not disclosed. The Company generally considers a payment delay of three months or less to be insignificant. • Term extensions – Extensions of the original contractual maturity date of the loan. • Combination – Combination includes loans that have undergone more than one of the above loan modification types. Significant judgment is required to determine if a borrower is experiencing financial difficulty. These considerations vary by portfolio class. The Company has identified modifications to borrowers experiencing financial difficulty that are included in its disclosures as follows: • Commercial: The Company evaluates modifications of loans to commercial borrowers that are rated substandard or worse, and includes the modification in its disclosures to the extent that the modification is considered • Consumer: The Company generally evaluates all modifications of loans to consumer borrowers subject to its loss mitigation program and includes them in its disclosures to the extent that the modification is considered other-than-insignificant. The following table summarizes the amortized cost basis at December 31, 2023, of loans modified to borrowers experiencing financial difficulty, disaggregated by class and type of concession granted: For the year ended December 31, 2023 (In thousands) Interest Rate Reduction Term Extension Payment Delay CombinationTerm Extension & Interest Rate Reduction CombinationTerm Extension & Payment Delay CombinationInterest Rate Reduction & Payment Delay CombinationTerm Extension, Interest Rate Reduction, & Payment Delay Total % of Total Class (2) Commercial non-mortgage $ — $ 96,895 $ 5,858 $ 1,062 $ 28,860 $ 35 $ 425 $ 133,135 0.8 % Asset-based — 45,042 — — — — — 45,042 2.9 Commercial real estate — 3,090 174 17,107 511 — — 20,882 0.2 Equipment financing — 357 1,284 — — — — 1,641 0.1 Residential — 186 804 136 — — — 1,126 — Home equity 62 76 — 513 — — — 651 — Total (1) $ 62 $ 145,646 $ 8,120 $ 18,818 $ 29,371 $ 35 $ 425 $ 202,477 0.4 % (1) The total amortized cost excludes accrued interest receivable of $0.7 million for the year ended December 31, 2023. (2) Represents the total amortized cost of the loans modified as a percentage of the total period end loan balance by class. The following table describes the financial effect of the modifications made to borrowers experiencing financial difficulty: For the year ended December 31, 2023 Financial Effect Interest Rate Reduction: Home equity Reduced weighted average interest rate by 0.5% Term Extension: Commercial non-mortgage Extended term by a weighted average of 1.3 years Asset-based Extended term by a weighted average of 0.7 years Commercial real estate Extended term by a weighted average of 2.2 years Equipment financing Extended term by a weighted average of 4.5 years Residential Extended term by a weighted average of 2.8 years Home equity Extended term by a weighted average of 10.1 years Payment Delay: Commercial non-mortgage Provided partial payment deferrals for a weighted average of 0.5 years Commercial real estate Provided payment deferrals for a weighted average of 0.3 years to be received at contractual maturity Equipment financing Provided partial payment deferrals for a weighted average of 0.5 years Residential Provided payment deferrals for a weighted average of 1.0 year Combination Term Extension & Interest Rate Reduction: Commercial non-mortgage Extended term by a weighted average of 1.4 years and reduced weighted average interest rate by 1.8% Commercial real estate Extended term by a weighted average of 3.0 years and reduced weighted average interest rate by 2.4% Residential Extended term by a weighted average of 17.9 years and reduced weighted average interest rate by 0.3% Home equity Extended term by a weighted average of 16.8 years and reduced weighted average interest rate by 2.1% Combination Term Extension & Payment Delay: Commercial non-mortgage Extended term by a weighted average of 1.1 years and provided partial payment deferrals for a weighted average of 1.0 year Commercial real estate Extended term by a weighted average of 0.5 years and provided payment deferrals for a weighted average of 0.5 years Combination Interest Rate Reduction & Payment Delay: Commercial non-mortgage Reduced weighted average interest rate by 2.0% and provided payment deferrals for a weighted average of 0.5 years Combination Term Extension, Interest Rate Reduction, & Payment Delay: Commercial non-mortgage Extended term by a weighted average of 0.5 years, reduced weighted average interest rate by 2.0%, and provided payment deferrals for a weighted average of 0.5 years The Company closely monitors the performance of the loans that are modified to borrowers experiencing financial difficulty to understand the effectiveness of its modification efforts. The following table summarizes the aging of loans that have been modified in the year ended December 31, 2023: At December 31, 2023 (In thousands) Current 30-59 Days 60-89 Days 90+ Days Non-Accrual Total Commercial non-mortgage $ 107,852 $ — $ — $ — $ 25,283 $ 133,135 Asset-based 45,042 — — — — 45,042 Commercial real estate 20,708 — — — 174 20,882 Equipment financing 1,284 — — — 357 1,641 Residential 990 — — — 136 1,126 Home equity 547 — — — 104 651 Total $ 176,423 $ — $ — $ — $ 26,054 $ 202,477 Loans made to borrowers experiencing financial difficulty that were modified during the year ended December 31, 2023, and that subsequently defaulted were not significant. For the purposes of this disclosure, a payment default is defined as 90 or more days past due and still accruing. Non-accrual loans that are modified to borrowers experiencing financial difficulty remain on non-accrual status until the borrower has demonstrated performance under the modified terms. Commitments to lend additional funds to borrowers experiencing financial difficulty whose loans had been modified were not significant. Troubled Debt Restructurings Prior to the Adoption of ASU 2022-02 The following table summarizes information related to TDRs: (In thousands) At December 31, 2022 Accrual status $ 110,868 Non-accrual status 83,954 Total TDRs $ 194,822 Additional funds committed to borrowers in TDR status $ 1,724 Specific reserves for TDRs included in the ACL on loans and leases: Commercial portfolio $ 14,578 Consumer portfolio 3,559 The following table summarizes loans and leases modified as TDRs by class and modification type: Years ended December 31, 2022 2021 Number of Recorded Investment (1) Number of Recorded Investment (1) (Dollars in thousands) Commercial non-mortgage: Extended maturity 5 $ 291 8 $ 605 Maturity / rate combined 8 765 9 352 Other (2) 19 52,070 12 14,160 Asset-based: Other (2) 1 23,298 — — Commercial real estate: Extended maturity — — 1 183 Other (2) — — 1 1,582 Equipment financing: Other (2) 3 1,692 — — Residential: Extended maturity 2 1,185 1 99 Maturity / rate combined 2 133 2 401 Other (2) 8 3,158 3 280 Home equity: Extended maturity — — 85 1,809 Adjusted interest rate 1 74 — — Maturity / rate combined 21 2,623 6 1,025 Other (2) 37 2,134 22 1,481 Total TDRs 107 $ 87,423 150 $ 21,977 (1) Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs due to restructurings was not significant. (2) Other includes covenant modifications, forbearance, discharges under Chapter 7 bankruptcy, or other concessions. For the years ended December 31, 2022, and 2021, the portion of TDRs deemed to be uncollectible and charged-off were $14.7 million and $3.0 million for the commercial portfolio, respectively, and $0.3 million and $0.4 million for the consumer portfolio, respectively.

Transfers of Financial Assets

Transfers of Financial Assets	12 Months Ended
	Dec. 31, 2023
Transfers and Servicing [Abstract]
Transfers of Financial Assets	Transfers and Servicing of Financial Assets The Company originates and sells residential mortgage loans in the normal course of business, primarily to government-sponsored entities through established programs and securitizations. Residential mortgage origination fees, adjustments for changes in fair value, and any gain or loss recognized on residential mortgage loans sold are included in Mortgage banking activities The following table summarizes information related to mortgage banking activities: Years ended December 31, (In thousands) 2023 2022 2021 Net gain on sale $ 1,126 $ 580 $ 5,192 Origination fees 68 219 1,440 Fair value adjustments 46 (94) (413) Mortgage banking activities $ 1,240 $ 705 $ 6,219 Proceeds from sale $ 13,882 $ 36,335 $ 247,634 Loans sold with servicing rights retained 6,499 32,056 237,834 Under certain circumstances, the Company may decide to sell loans that were not originated or otherwise acquired with the intent to sell. During the years ended December 31, 2023, 2022, and 2021, the Company sold loans not originated for sale for proceeds of $626.0 million, $679.7 million, and $82.2 million, respectively, which resulted in net gains on sale of $0.9 million, $3.3 million, and $3.9 million, respectively. At December 31, 2023, and 2022, the aggregate principal balance of residential mortgage loans serviced for others was $1.8 billion and $2.0 billion, respectively. The Company may retain servicing rights on its residential mortgage loans sold in the normal course of business. Mortgage servicing rights are held at the lower of cost, net of accumulated amortization, or fair market value, and are included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. The Company assesses mortgage servicing rights for impairment each quarter and establishes or adjusts the valuation allowance to the extent that amortized cost exceeds the estimated fair market value. The following table presents the change in the carrying amount for mortgage servicing rights: Years ended December 31, (In thousands) 2023 2022 2021 Balance, beginning of period $ 9,515 $ 9,237 $ 13,422 Acquired from Sterling — 859 — Additions 71 289 2,053 Amortization (1) (1,063) (870) (5,593) Adjustment to valuation allowance — — (645) Balance, end of period $ 8,523 $ 9,515 $ 9,237 (1) The Company implemented a change in the method of amortization applied to its mortgage servicing rights during the year ended December 31, 2022, to better reflect the pattern of consumption, where estimated future cash flows are now assessed at the individual loan level as opposed to on a pooled basis. During the fourth quarter of 2023, the Company committed to and initiated a plan to actively market and sell the majority of its mortgage servicing portfolio (over nine thousand individual mortgage loans with an aggregate unpaid principal balance of approximately $1.4 billion). The Company treated the related mortgage servicing rights as assets held for disposition and ceased recognizing amortization expense on these assets. At December 31, 2023, the carrying amount of mortgage servicing rights held for disposition was $8.3 million. The Company expects the sale to close in the first quarter of 2024. Loan servicing fees, net of mortgage servicing rights amortization, for the years ended December 31, 2023, 2022, and 2021, totaled $4.0 million, $5.9 million, and $1.7 million, respectively, and are included in Loan and lease related fees on the accompanying Consolidated Statements of Income. Information regarding the fair value of loans held for sale and mortgage servicing rights can be found within Note 18: Fair Value Measurements.

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment The following table summarizes the components of premises and equipment: At December 31, (In thousands) 2023 2022 Land $ 73,916 $ 73,916 Buildings and improvements 107,794 106,180 Leasehold improvements 88,065 84,477 Furniture, fixtures, and equipment 68,680 71,542 Data processing equipment and software 94,030 128,153 Property and equipment 432,485 464,268 Less: Accumulated depreciation and amortization (186,365) (225,152) Property and equipment, net 246,120 239,116 ROU lease assets, net 183,441 191,068 Premises and equipment, net $ 429,561 $ 430,184 Depreciation and amortization of property and equipment was $34.7 million, $41.7 million, and $31.4 million for the years ended December 31, 2023, 2022, and 2021, respectively, and is included in both Occupancy and Technology and equipment expense on the accompanying Consolidated Statements of Income. The Company recognized $4.6 million and $6.3 million in losses on disposals of property and equipment for the years ended December 31, 2023, and 2022, respectively, which primarily pertained to retired internal use software and construction in progress due to the Company's decision to stop further project development. Losses on disposal of property and equipment for the year ended December 31, 2021, were not significant. Additional information regarding ROU lease assets can be found within Note 7: Leasing. Property Held for Sale Assets held for disposition are included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. During the year ended December 31, 2022, the Company launched and completed a corporate real estate consolidation strategy in which the Company closed 14 locations in order to reduce its corporate real estate facility square footage by approximately 45%. In connection with this corporate real estate consolidation plan, in the third quarter of 2022, the Company had arranged to sell its New Britain, Connecticut facility, which comprised of land, buildings, and improvements, within the next twelve months. This resulted in a $1.8 million write-down to the fair market value of the property and the subsequent transfer of the property, which was valued at $4.8 million, to assets held for disposition. The sale of the New Britain property closed during the third quarter of 2023. The Company received cash proceeds of $4.1 million and recognized a loss on sale of $0.7 million.

Leasing

Leasing	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Leasing	Leasing Lessor Arrangements The Company leases certain types of machinery and equipment to its customers through sales-type and direct financing leases as part of its equipment financing portfolio. These leases generally have remaining lease terms of one The following table summarizes the components of the Company's net investment in its sales-type and direct financing leases: At December 31, (In thousands) 2023 2022 Lease receivables $ 347,827 $ 330,690 Unguaranteed residual values 60,747 100,368 Total net investment $ 408,574 $ 431,058 The following table reconciles undiscounted future lease payments to the total sales-type and direct financing leases' net investment: (In thousands) At December 31, 2023 2024 $ 116,506 2025 107,211 2026 98,157 2027 51,058 2028 31,179 Thereafter 44,911 Total lease payments receivable 449,022 Present value adjustment (40,448) Total net investment $ 408,574 Lessee Arrangements The Company enters into operating leases in the normal course of business, primarily for office space, banking centers, and other operational activities. These leases generally have remaining lease terms of one The following table summarizes the Company's ROU lease assets and operating lease liabilities: At December 31, (In thousands) Consolidated Balance Sheet Line Item 2023 2022 ROU lease assets Premises and equipment, net $ 183,441 $ 191,068 Operating lease liabilities Accrued expenses and other liabilities 222,439 239,281 ROU lease asset impairment charges were zero, $23.1 million and $1.2 million for the years ended December 31, 2023, 2022, and 2021, respectively, and are included in Occupancy on the accompanying Consolidated Statements of Income. The ROU lease asset impairment charge recognized for the year ended December 31, 2022, pertained to the Company's corporate real estate consolidation plan, discussed previously in Note 6: Premises and Equipment, and was calculated as the difference between the estimated fair value of the assets determined using a discounted cash flow technique, relative to their book value. The following table summarizes the components of operating lease expense and other relevant information: At or for the Years ended December 31, (In thousands) 2023 2022 2021 Lease Cost: Operating and variable lease costs $ 38,497 $ 44,654 $ 30,936 Sublease income (223) (1,383) (554) Total operating lease expense $ 38,274 $ 43,271 $ 30,382 Other Information: Cash paid for amounts included in the measurement of operating lease liabilities $ 37,615 $ 44,767 $ 30,487 ROU lease assets obtained in exchange for operating lease liabilities (1) 22,989 27,897 15,226 Weighted-average remaining lease term (in years) 7.46 7.72 7.50 Weighted-average discount rate 2.96 % 2.65 % 3.04 % (1) The amount for the year ended December 31, 2022, excludes ROU lease assets acquired from Sterling in the merger. The following table reconciles undiscounted future lease payments to total operating lease liabilities: (In thousands) At December 31, 2023 2024 $ 38,575 2025 39,449 2026 35,665 2027 31,128 2028 26,999 Thereafter 81,918 Total operating lease payments 253,734 Present value adjustment (31,295) Total operating lease liabilities $ 222,439

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill The following table summarizes changes in the carrying amount of goodwill: At December 31, (In thousands) 2023 2022 Balance, beginning of period $ 2,514,104 $ 538,373 interLINK acquisition 143,216 — Sterling merger (1) (25,561) 1,939,765 Bend acquisition (1) (294) 35,966 Balance, end of period $ 2,631,465 $ 2,514,104 (1) The 2023 changes reflect adjustments recorded within the one-year measurement period, which were identified in the first quarter as a result of extended information gathering and new information that arose from integration activities. The allocation of the purchase price and goodwill calculations for both the Sterling merger and Bend acquisition were final as of March 31, 2023. Information regarding goodwill by reportable segment can be found within Note 21: Segment Reporting. Other Intangible Assets The following table summarizes other intangible assets: At December 31, 2023 2022 (In thousands) Gross Carrying Amount (1) Accumulated Net Carrying Gross Carrying Accumulated Net Carrying Core deposits $ 146,037 $ 53,986 $ 92,051 $ 146,037 $ 36,710 $ 109,327 Customer relationships (1) 151,000 43,116 107,884 115,000 24,985 90,015 Non-competition agreement (1) 4,000 800 3,200 — — — Other intangible assets $ 301,037 $ 97,902 $ 203,135 $ 261,037 $ 61,695 $ 199,342 (1) The increase in the gross carrying amount is attributed to the acquisition of interLINK during the first quarter of 2023, in which the Company identified and recorded a $36.0 million intangible asset for broker dealer relationships, which is being amortized on an accelerated basis over an estimated useful life of 10 years, and a $4.0 million non-competition agreement, which is being amortized on a straight-line basis over an estimated useful life of 5 years. The remaining estimated aggregate future amortization expense for other intangible assets is as follows: (In thousands) At December 31, 2024 $ 29,618 2025 25,956 2026 25,565 2027 25,565 2028 23,216 Thereafter 73,215

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense reflects the following expense (benefit) components: Years ended December 31, (In thousands) 2023 2022 2021 Current: Federal $ 219,548 $ 170,779 $ 109,621 State and local 50,750 52,579 20,374 Total current 270,298 223,358 129,995 Deferred: Federal (43,615) (45,421) (9,844) State and local (10,019) (24,243) 4,846 Total deferred (53,634) (69,664) (4,998) Total federal 175,933 125,358 99,777 Total state and local 40,731 28,336 25,220 Income tax expense $ 216,664 $ 153,694 $ 124,997 Included in the Company's income tax expense for the years ended December 31, 2023, 2022, and 2021, are net tax credits of approximately $11.9 million, $14.0 million, and $2.6 million, respectively. These amounts relate primarily to LIHTC investments and include associated SALT credits and benefits. Also included in the Company's income tax expense for the years ended December 31, 2023, 2022, and 2021 are benefits from operating loss carryforwards of $0.2 million, $10.3 million, and $0.4 million, respectively. The 2022 amount includes a $9.9 million benefit related to a reduction in the Company's beginning-of-year valuation allowance for its SALT DTAs. The following table reflects a reconciliation of reported income tax expense to the amount that would result from applying the federal statutory rate of 21.0%: Years ended December 31, 2023 2022 2021 (In thousands) Amount Percent Amount Percent Amount Percent Income tax expense at federal statutory rate $ 227,746 21.0 % $ 167,575 21.0 % $ 112,111 21.0 % Reconciliation to reported income tax expense: SALT expense, net of federal 32,177 3.0 32,259 4.1 19,924 3.7 Tax-exempt interest income, net (44,473) (4.1) (35,371) (4.4) (6,814) (1.3) Increase in cash surrender value of life insurance (5,469) (0.5) (6,122) (0.8) (3,030) (0.6) Non-deductible FDIC deposit insurance premiums 10,693 1.0 5,581 0.7 2,064 0.4 Low income housing tax credits and other benefits, net (3,866) (0.4) (7,627) (1.0) (615) (0.1) Non-deductible compensation expense 4,167 0.4 7,948 1.0 786 0.1 Non-deductible merger-related expenses, excluding compensation 45 — 2,717 0.3 3,451 0.7 DTA valuation allowance adjustment, net (368) — (9,874) (1.2) — — Other, net (3,988) (0.4) (3,392) (0.4) (2,880) (0.5) Income tax expense and effective tax rate $ 216,664 20.0 % $ 153,694 19.3 % $ 124,997 23.4 % The following table reflects the significant components of DTAs, net: At December 31, (In thousands) 2023 2022 Deferred tax assets: ACL on loans and leases $ 171,870 $ 161,932 Net operating loss and credit carry forwards 68,103 72,035 Compensation and employee benefit plans 46,670 55,093 Lease liabilities under operating leases 60,331 64,899 Net unrealized loss on available-for-sale securities 191,922 233,978 Other 72,546 38,314 Gross deferred tax assets 611,442 626,251 Valuation allowance (28,746) (29,176) Total deferred tax assets, net of valuation allowance $ 582,696 $ 597,075 Deferred tax liabilities: ROU assets under operating leases $ 49,754 $ 51,822 Equipment financing leases 54,300 74,295 Goodwill and other intangible assets 59,817 56,223 Purchase accounting and fair value adjustments 15,527 11,529 Other 34,086 31,572 Gross deferred tax liabilities 213,484 225,441 Deferred tax assets, net $ 369,212 $ 371,634 The Company's net DTAs decreased by $2.4 million during 2023, reflecting a $49.7 million expense allocated directly to (AOCL) and a $7.9 million net DTL recognized as part of purchase accounting adjustments related to the merger with Sterling and acquisition of Bend, partially offset by the $53.6 million deferred tax benefit and a $1.6 million benefit recorded to equity upon the adoption of ASU 2022-02 . The valuation allowance of $28.7 million at December 31, 2023, is primarily attributable to SALT net operating loss carryforwards, as compared to $29.2 million at December 31, 2022, consisting of approximately $28.6 million attributable to SALT net operating loss carryforwards and $0.6 million of federal credit carryforwards. The net decrease in the valuation allowance during 2023 primarily reflects a reduction in the beginning-of-year valuation allowance related to a change in management's estimate about the realizability of the Company's federal credits. SALT net operating loss carryforwards approximated $1.1 billion at December 31, 2023, including those related to the Sterling merger and Bend acquisition, and are generally scheduled to expire in varying amounts during tax years 2024 through 2032. Federal net operating loss carryforwards of approximately $16.8 million and federal credit carryforwards of $0.4 million at December 31, 2023, related to the Bend acquisition are subject to annual limitations on utilization, with the net operating losses able to be carried forward indefinitely and the credits scheduled to expire in varying amounts between 2038 and 2042. The valuation allowance reflects approximately $486.6 million of those SALT net operating loss carryforwards that are estimated to expire unused. Management believes it is more likely than not that the results of future operations will generate sufficient taxable income to realize its total DTAs, net of the valuation allowance. Although taxable income in prior years is no longer able to be included as a source of taxable income, due to the general repeal of the carryback of net operating losses under the Tax Cuts and Jobs Act of 2017, significant positive evidence remains in support of management's conclusion regarding the realizability of the Company's DTAs, including projected future reversals of existing taxable temporary differences and book-taxable income levels in recent years and projected in future years. There can, however, be no assurance that any specific level of future income will be generated or that the Company’s DTAs will ultimately be realized. DTLs of $63.2 million at both December 31, 2023, and 2022, have not been recognized for certain thrift bad-debt reserves, established before 1988, that would become taxable upon the occurrence of certain events: distributions by the Bank in excess of certain earnings and profits; the redemption of the Bank’s stock; or liquidation. The Company does not expect any of those events to occur. At both December 31, 2023, and 2022, the cumulative taxable temporary differences applicable to those reserves approximated $233.1 million. The following table reflects a reconciliation of the beginning and ending balances of UTBs: Years ended December 31, (In thousands) 2023 2022 2021 Beginning balance $ 9,875 $ 4,249 $ 4,252 Additions as a result of tax positions taken during the current year 359 223 294 Additions as a result of tax positions taken during prior years 4,255 8,807 434 Reductions as a result of tax positions taken during prior years — (503) (186) Reductions relating to settlements with taxing authorities — (2,110) (267) Reductions as a result of lapse of statute of limitation periods (653) (791) (278) Ending balance $ 13,836 $ 9,875 $ 4,249 At December 31, 2023, 2022, and 2021, there were $12.4 million, $9.1 million, and $3.5 million, respectively, of UTBs that if recognized would affect the effective tax rate. The Company recognizes interest and penalties related to UTBs, where applicable, in income tax expense. The Company recognized expense of $1.8 million, $0.1 million, and $0.3 million during the years ended December 31, 2023, 2022, and 2021, respectively. At December 31, 2023 and 2022, the Company had accrued interest and penalties related to UTBs of $3.8 million and $2.0 million respectively. The Company has determined it is reasonably possible that its total UTBs could decrease by between $0.4 million and $9.3 million by the end of 2024 as a result of potential lapses in statute-of-limitation periods and/or potential settlements with taxing authorities, primarily concerning various depreciation and state and local apportionment and tax-base determinations. The Company's federal tax returns for all years subsequent to 2018 remain open to examination, including the carryback of a Sterling 2019 net operating loss under the CARES Act in 2020 to tax years 2014 and 2016, currently under audit by the Internal Revenue Service. The Company's tax returns filed in its other principal tax jurisdictions of Connecticut, New York State, New York City, Massachusetts and New Jersey for years subsequent to 2014 are either under or remain open to examination.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2023
Deposit Liabilities [Abstract]
Deposits	Deposits The following table summarizes deposits by type: At December 31, (In thousands) 2023 2022 Non-interest-bearing: Demand $ 10,732,516 $ 12,974,975 Interest-bearing: Health savings accounts 8,287,889 7,944,892 Checking 8,994,095 9,237,529 Money market 17,662,826 11,062,652 Savings 6,642,499 8,673,343 Time deposits 8,464,459 4,160,949 Total interest-bearing 50,051,768 41,079,365 Total deposits $ 60,784,284 $ 54,054,340 Time deposits, money market, and interest-bearing checking obtained through brokers (1) $ 3,673,733 $ 1,964,873 Aggregate amount of time deposit accounts that exceeded the FDIC limit 1,221,887 1,894,950 Demand deposit overdrafts reclassified as loan balances 10,432 8,721 (1) Excludes $5.7 billion of interLINK money market sweep deposits at December 31, 2023. The following table summarizes the scheduled maturities of time deposits: (In thousands) At December 31, 2023 2024 $ 8,217,683 2025 138,769 2026 53,807 2027 32,865 2028 21,335 Total time deposits $ 8,464,459

Borrowings

Borrowings	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Borrowings	Borrowings The following table summarizes securities sold under agreements to repurchase and other borrowings: At December 31, 2023 2022 (In thousands) Total Outstanding Rate Total Outstanding Rate Securities sold under agreements to repurchase (1) $ 358,387 3.43 % $ 282,005 0.11 % Federal funds purchased 100,000 5.48 869,825 4.44 Securities sold under agreements to repurchase and other borrowings $ 458,387 3.88 % $ 1,151,830 3.38 % (1) The Company has the right of offset with respect to all repurchase agreement assets and liabilities. Total securities sold under agreements to repurchase are presented as gross transactions, as only liabilities are outstanding for the periods presented. Securities sold under agreements to repurchase, all of which have an original maturity of one year or less for the periods presented, are used as a source of borrowed funds and are collateralized by Agency MBS and Corporate debt. The Company's repurchase agreement counterparties are limited to primary dealers in government securities, and commercial and municipal customers through the Corporate Treasury function. The Company may also purchase unsecured term and overnight federal funds to satisfy its short-term liquidity needs. The following table summarizes information for FHLB advances: At December 31, 2023 2022 (In thousands) Total Weighted-Average Contractual Coupon Rate Total Weighted-Average Contractual Coupon Rate Maturing within 1 year $ 2,350,000 5.53 % $ 5,450,187 4.40 % After 1 but within 2 years — — — — After 2 but within 3 years — — — — After 3 but within 4 years 235 — — — After 4 but within 5 years 228 2.75 252 — After 5 years 9,555 2.07 10,113 2.09 FHLB advances $ 2,360,018 5.52 % $ 5,460,552 4.39 % Aggregate market value of assets pledged as collateral $ 20,734,035 $ 13,692,379 Remaining borrowing capacity at FHLB 12,535,423 4,291,326 The Bank may borrow up to the amount of eligible mortgages and securities that have been pledged as collateral to secure FHLB advances, which includes certain residential and commercial real estate loans, home equity lines of credit, CMBS, Agency MBS, Agency CMO, and U.S. Treasury notes. The Bank was in compliance with its FHLB collateral requirements at both December 31, 2023, and 2022. The following table summarizes long-term debt: At December 31, (In thousands) 2023 2022 4.375% Senior fixed-rate notes due February 15, 2024 (2) $ 132,550 $ 150,000 4.100 % Senior fixed-rate notes due March 25, 2029 (3) 328,104 333,458 4.000% Subordinated fixed-to-floating rate notes due December 30, 2029 274,000 274,000 3.875 % Subordinated fixed-to-floating rate notes due November 1, 2030 225,000 225,000 Junior subordinated debt Webster Statutory Trust I floating-rate notes due September 17, 2033 (4) 77,320 77,320 Total senior and subordinated debt 1,036,974 1,059,778 Discount on senior fixed-rate notes (537) (756) Debt issuance cost on senior fixed-rate notes (1,419) (1,824) Premium on subordinated fixed-to-floating rate notes 13,802 15,930 Long-term debt (1) $ 1,048,820 $ 1,073,128 (1) The classification of debt as long-term is based on the initial terms of greater than one year as of the date of issuance. (2) The Company repurchased and retired $17.5 million of these senior notes at 96 cents on the dollar in May 2023. The resulting (3) The Company de-designated its fair value hedging relationship on these senior notes in 2020. A basis adjustment of $28.1 million and $33.5 million at December 31, 2023, and 2022, respectively, is included in the carrying value and is being amortized over the remaining life of the senior notes. (4) The interest rate on the Webster Statutory Trust I floating-rate notes varies quarterly based on 3-month SOFR plus a credit spread adjustment plus a market spread of 2.95%. Prior to LIBOR cessation on July 1, 2023, the notes varied quarterly based on 3-month LIBOR plus a market spread of 2.95%. The interest rates yielded 8.59% and 7.69% at December 31, 2023, and 2022, respectively. The Company assumed $274.0 million in aggregate principal amount of 4.00% fixed-to-floating rate subordinated notes due on December 30, 2029 (the 2029 subordinated notes), in connection with the Sterling merger. The 2029 subordinated notes were issued by Sterling on December 16, 2019, through a public offering, and are redeemable at a price equal to the total principal amount plus any accrued and unpaid interest thereon, in whole or in part by the Company on December 30, 2024, or any interest payment date thereafter, upon the occurrence of certain specified events. Until December 30, 2024, the interest rate is fixed at 4.00% and payable semi-annually in arrears on each June 30 and December 30. From and including December 30, 2024, through the earlier of maturity or redemption, the 2029 subordinated notes will bear interest at a floating rate per annum equal to three-month term SOFR plus 253 basis points, payable quarterly in arrears on March 30, June 30, September 30, and December 30 of each year, commencing on March 30, 2025. The Company also assumed $225.0 million in aggregate principal amount of 3.875% fixed-to-floating rate subordinated notes due on November 1, 2030 (the 2030 subordinated notes), in connection with the Sterling merger. The 2030 subordinated notes were issued by Sterling on October 30, 2020, through a public offering, and are redeemable at a price equal to the total principal amount plus any accrued and unpaid interest thereon, in whole or in part by the Company on November 1, 2025, or any interest payment date thereafter, upon the occurrence of certain specified events. Until November 1, 2025, the interest rate is fixed at 3.875% and payable semi-annually in arrears on each May 1 and November 1. From and including November 1, 2025, through the earlier of maturity or redemption, the 2030 subordinated notes will bear interest at a floating rate per annum equal to three-month term SOFR plus 369 basis points, payable quarterly in arrears on February 1, May 1, August 1, and November 1 of each year, commencing on February 1, 2026. The Company recorded the 2029 and 2030 subordinated notes at their estimated fair value of $281.0 million and $235.9 million, respectively, on January 31, 2022. The corresponding purchase premiums are being amortized into interest expense over the remaining lives of the subordinated notes.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity The following table summarizes the changes in shares of preferred and common stock issued and common stock held as treasury shares for the year ended December 31, 2023: Preferred Stock Series F Issued Preferred Stock Series G Issued Common Stock Issued Treasury Stock Held Common Stock Outstanding Balance, beginning of period 6,000 135,000 182,778,045 8,770,472 174,007,573 Restricted stock compensation plan activity — — — (605,684) 605,684 Stock options exercised — — — (75,848) 75,848 Common stock repurchase program — — 2,667,149 (2,667,149) Balance, end of period 6,000 135,000 182,778,045 10,756,089 172,021,956 Repurchases of Common Stock The Company maintains a common stock repurchase program, which was approved by the Board of Directors on In addition, the Company will periodically acquire Webster common stock outside of the repurchase program related to employee stock compensation plan activity. During the year ended December 31, 2023, the Company repurchased 315,729 shares at a weighted-average price of $51.48 per share, totaling $16.3 million for this purpose. Contribution to Charitable Foundation On July 8, 2022, the Company made an unrestricted and unconditional contribution of Webster common shares to the Webster Bank Charitable Foundation, a nonprofit charitable organization with a focus on education and community development that serves communities in the Greater New York City, Lower Hudson Valley, Long Island, and New Jersey areas. The fair value of these shares based on their closing price on the contribution date was $10.5 million. Change in Common Shares Authorized The number of authorized shares of Webster common stock was increased from 200.0 million shares to 400.0 million shares on January 31, 2022, in connection with the completion of the merger with Sterling and in accordance with the merger agreement. Series F Preferred Stock On December 12, 2017, the Company closed on a public offering of 6,000,000 depositary shares, each representing 1/1000th ownership interest in a share of 5.25% Series F Non-Cumulative Preferred Perpetual Stock, par value $0.01 per share, with a liquidation preference equal to $25,000 per share (the Series F Preferred Stock). Dividends on the Series F Preferred Stock are non-cumulative and are not mandatory. If declared by the Board of Directors, or a duly authorized committee thereof, the Company will pay dividends quarterly in arrears on the fifteenth day of each March, June, September, and December, at a rate equal to 5.25% of the $25,000 per share liquidation amount per annum. If a dividend on the Series F Preferred Stock is not declared in respect of a dividend period, a dividend will not accrue and the Company has no obligation to pay any dividend for that period, regardless as to whether a dividend is declared for a future period on the Series G Preferred Stock or any other series of Webster preferred stock. The terms of the Series F Preferred Stock prohibit the Company from declaring or paying any cash dividends on Webster common stock, and from repurchasing, redeeming, or otherwise acquiring Webster common stock or any other series of Webster preferred stock to which it ranks on parity with, unless dividends have been declared and paid in full on the Series F Preferred Stock for the most recent dividend period. The Series F Preferred Stock is perpetual and has no maturity date, and is not subject to any mandatory redemption, sinking fund, or other similar provisions. Except with respect to certain non-payment events and certain changes to the terms of the Series F Preferred Stock, holders have no voting rights nor preemptive or conversion rights. The Series F Preferred Stock is not convertible or exchangeable for shares of any other class of Webster stock. Series G Preferred Stock On January 31, 2022, in connection with the Sterling merger, the Company registered and issued 5,400,000 depositary shares, each representing 1/40th interest in a share of 6.50% Series G Non-Cumulative Preferred Perpetual Stock, par value $0.01 per share, with a liquidation preference equal to $1,000 per share (the Series G Preferred Stock). The Series G Preferred Stock ranks on parity with the Series F Preferred Stock and senior to Webster common stock, with respect to the payment of dividends and distributions upon the liquidation, dissolution, or winding-up of the Company. Dividends on the Series G Preferred Stock are non-cumulative and are not mandatory. If declared by the Board of Directors, or a duly authorized committee thereof, the Company will pay dividends quarterly in arrears on the fifteenth day of each The Series G Preferred Stock is perpetual and has no maturity date, and is not subject to any mandatory redemption, sinking fund, or other similar provisions. Except with respect to certain non-payment events and certain changes to the terms of the Series G Preferred Stock, holders have no voting rights, nor preemptive or conversion rights. The Series G Preferred Stock is not convertible or exchangeable for shares of any other class of Webster stock. Preferred Stock Redemptions The Company may redeem either the Series F Preferred Stock or the Series G Preferred Stock at its option, in whole or in part, subject to the approval of Federal Reserve Board, on any dividend payment date, or in whole but not in part, upon the occurrence of a regulatory capital treatment event, at a redemption price equal to the liquidation preference plus any declared and unpaid dividends, without accumulation of any undeclared dividends. The Company has no plans to redeem either its Series F Preferred Stock or its Series G Preferred stock, in whole or in part, as of the date of this Annual Report on Form 10-K.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss, Net of Tax	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Accumulated Other Comprehensive Loss, Net of Tax	Accumulated Other Comprehensive (Loss) Income, Net of Tax The following table summarizes the changes in each component of accumulated other comprehensive (loss) income, net of tax: (In thousands) Investment Securities Available- Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Balance at December 31, 2020 $ 67,424 $ 19,918 $ (45,086) $ 42,256 Other comprehensive (loss) income before reclassifications (62,888) (17,109) 8,876 (71,121) Amounts reclassified from accumulated other comprehensive — 3,261 3,024 6,285 Other comprehensive (loss) income, net of tax (62,888) (13,848) 11,900 (64,836) Balance at December 31, 2021 4,536 6,070 (33,186) (22,580) Other comprehensive (loss) before reclassifications (640,656) (17,810) (13,350) (671,816) Amounts reclassified from accumulated other comprehensive income (loss) 4,960 2,866 1,610 9,436 Other comprehensive (loss), net of tax (635,696) (14,944) (11,740) (662,380) Balance at December 31, 2022 (631,160) (8,874) (44,926) (684,960) Other comprehensive income before reclassifications 86,391 4,066 11,794 102,251 Amounts reclassified from accumulated other comprehensive 27,319 1,939 2,880 32,138 Other comprehensive income, net of tax 113,710 6,005 14,674 134,389 Balance at December 31, 2023 $ (517,450) $ (2,869) $ (30,252) $ (550,571) The following table further summarizes the amounts reclassified from accumulated other comprehensive (loss) income: Years ended December 31, Accumulated Other Comprehensive (Loss) Income Components 2023 2022 2021 Associated Line Item in the Consolidated Statement Of Income (In thousands) Investment securities available-for-sale: Net unrealized holding (losses) $ (37,356) $ (6,751) $ — (Loss) on sale of investment securities (1) Tax benefit 10,037 1,791 — Income tax expense Net of tax $ (27,319) $ (4,960) $ — Derivative instruments: Hedge terminations $ (310) $ (306) $ (306) Interest expense Premium amortization (2,349) (3,626) (4,109) Interest income Tax benefit 720 1,066 1,154 Income tax expense Net of tax $ (1,939) $ (2,866) $ (3,261) Defined benefit pension and other postretirement benefit plans: Actuarial net loss amortization $ (2,083) $ (2,210) $ (4,102) Other expense Other (1,869) — — Other expense Tax benefit 1,072 600 1,078 Income tax expense Net of tax $ (2,880) $ (1,610) $ (3,024) (1) Losses recognized on the sale of investment securities are generally included as a component of non-interest income, unless any portion or all of the loss is attributed to a decline in credit quality, in which the amount recognized is then included in the Provision for credit losses. During the years ended December 31, 2023, and 2022, $3.8 million and zero of the total loss recognized on the sale of investment securities was included in the Provision for credit losses, respectively. The following tables summarize each component of other comprehensive income (loss) and the related tax effects: Year ended December 31, 2023 (In thousands) Amount Tax Benefit (Expense) Amount Investment securities available-for-sale: Net unrealized holding gains arising during the year $ 118,410 $ (32,019) $ 86,391 Reclassification adjustment for net realized losses included in net income 37,356 (10,037) 27,319 Total investment securities available-for-sale 155,766 (42,056) 113,710 Derivative instruments: Net unrealized gains arising during the year 5,578 (1,512) 4,066 Reclassification adjustment for net realized losses included in net income 2,659 (720) 1,939 Total derivative instruments 8,237 (2,232) 6,005 Defined benefit pension and other postretirement benefit plans: Net actuarial gain arising during the year 16,183 (4,389) 11,794 Reclassification adjustment for actuarial net loss amortization and other 3,952 (1,072) 2,880 Total defined benefit pension and postretirement benefit plans 20,135 (5,461) 14,674 Other comprehensive income, net of tax $ 184,138 $ (49,749) $ 134,389 Year ended December 31, 2022 (In thousands) Amount Tax Benefit (Expense) Amount Investment securities available-for-sale: Net unrealized holding (losses) arising during the year $ (878,366) $ 237,710 $ (640,656) Reclassification adjustment for net realized losses included in net income 6,751 (1,791) 4,960 Total investment securities available-for-sale (871,615) 235,919 (635,696) Derivative instruments: Net unrealized (losses) arising during the year (24,440) 6,630 (17,810) Reclassification adjustment for net realized losses included in net income 3,932 (1,066) 2,866 Total derivative instruments (20,508) 5,564 (14,944) Defined benefit pension and other postretirement benefit plans: Net actuarial (loss) arising during the year (18,319) 4,969 (13,350) Reclassification adjustment for net actuarial loss amortization included in net income 2,210 (600) 1,610 Total defined benefit pension and postretirement benefit plans (16,109) 4,369 (11,740) Other comprehensive (loss), net of tax $ (908,232) $ 245,852 $ (662,380) Year ended December 31, 2021 (In thousands) Amount Tax Benefit (Expense) Amount Investment securities available-for-sale: Net unrealized holding (losses) arising during the year $ (85,368) $ 22,480 $ (62,888) Total investment securities available-for-sale (85,368) 22,480 (62,888) Derivative instruments: Net unrealized (losses) arising during the year (23,216) 6,107 (17,109) Reclassification adjustment for net realized losses included in net income 4,415 (1,154) 3,261 Total derivative instruments (18,801) 4,953 (13,848) Defined benefit pension and other postretirement benefit plans: Net actuarial gain arising during the year 12,052 (3,176) 8,876 Reclassification adjustment for net actuarial loss amortization included in net income 4,102 (1,078) 3,024 Total defined benefit pension and postretirement benefit plans 16,154 (4,254) 11,900 Other comprehensive (loss), net of tax $ (88,015) $ 23,179 $ (64,836)

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2023
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Regulatory Matters	Regulatory Capital and Restrictions Capital Requirements The Holding Company and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory actions by regulators that could have a direct material effect on the Company’s financial statements. Under capital adequacy guidelines and/or the regulatory framework for prompt corrective action (applies to the Bank only), both the Holding Company and the Bank must meet specific capital guidelines that involve quantitative measures of assets, liabilities, and certain off-balance sheet items calculated pursuant to regulatory directives. Capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors. Quantitative measures established by Basel III to ensure capital adequacy require the Holding Company and the Bank to maintain minimum ratios of CET1 Risk-Based Capital, Tier 1 Risk-Based Capital, Total Risk-Based Capital, and Tier 1 Leverage Capital, as defined in the regulations. CET1 capital consists of common stockholders’ equity less deductions for goodwill and other intangible assets, and certain deferred tax adjustments. At the time of initial adoption of the Basel III Capital Rules, the Company had elected to opt-out of the requirement to include certain components of AOCI in CET1 capital. Tier 1 capital consists of CET1 capital plus preferred stock. Total capital consists of Tier 1 capital and Tier 2 capital, as defined in the regulations. Tier 2 capital includes qualifying subordinated debt and the permissible portion of the ACL. At December 31, 2023, and 2022, both the Holding Company and the Bank were classified as well-capitalized. Management believes that no events or changes have occurred subsequent to year-end that would change this designation. The following table provides information on the regulatory capital ratios for the Holding Company and the Bank: At December 31, 2023 Actual (1) Minimum Requirement Well Capitalized (In thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 Risk-Based Capital $ 6,188,433 11.11 % $ 2,507,190 4.5 % $ 3,621,497 6.5 % Tier 1 Risk-Based Capital 6,472,412 11.62 3,342,920 6.0 4,457,227 8.0 Total Risk-Based Capital 7,643,423 13.72 4,457,227 8.0 5,571,534 10.0 Tier 1 Leverage Capital 6,472,412 9.06 2,857,890 4.0 3,572,362 5.0 Webster Bank CET1 Risk-Based Capital $ 6,913,443 12.43 % $ 2,502,835 4.5 % $ 3,615,206 6.5 % Tier 1 Risk-Based Capital 6,913,443 12.43 3,337,113 6.0 4,449,484 8.0 Total Risk-Based Capital 7,494,332 13.47 4,449,484 8.0 5,561,855 10.0 Tier 1 Leverage Capital 6,913,443 9.69 2,855,212 4.0 3,569,015 5.0 At December 31, 2022 Actual (1) Minimum Requirement Well Capitalized (In thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 Risk-Based Capital $ 5,822,369 10.71 % $ 2,446,344 4.5 % $ 3,533,608 6.5 % Tier 1 Risk-Based Capital 6,106,348 11.23 3,261,792 6.0 4,349,056 8.0 Total Risk-Based Capital 7,203,029 13.25 4,349,056 8.0 5,436,320 10.0 Tier 1 Leverage Capital 6,106,348 8.95 2,730,212 4.0 3,412,765 5.0 Webster Bank CET1 Risk-Based Capital $ 6,661,504 12.28 % $ 2,442,058 4.5 % $ 3,527,417 6.5 % Tier 1 Risk-Based Capital 6,661,504 12.28 3,256,078 6.0 4,341,437 8.0 Total Risk-Based Capital 7,165,935 13.20 4,341,437 8.0 5,426,796 10.0 Tier 1 Leverage Capital 6,661,504 9.77 2,727,476 4.0 3,409,345 5.0 (1) In accordance with regulatory capital rules, the Company elected an option to delay the estimated impact of the adoption of CECL on its regulatory capital over a two-year deferral period, which ended on January 1, 2022, and a subsequent three-year transition period ending on December 31, 2024. During the three-year transition period, regulatory capital ratios will phase out the aggregate amount of the regulatory capital benefit provided from the delayed CECL adoption in the initial two years. For 2022, 2023, and 2024, the Company is allowed 75%, 50%, and 25%, respectively, of the regulatory capital benefit as of December 31, 2021, with full absorption occurring in 2025. Dividend Restrictions The Holding Company is dependent upon dividends from the Bank to provide funds for the payment of dividends to stockholders and for other cash requirements. Dividends paid by the Bank are subject to various federal and state regulatory limitations. Express approval by the OCC is required if the effect of dividends declared would cause the regulatory capital of the Bank to fall below specified minimum levels or if the amount would exceed net income for that year combined with undistributed net income for the preceding two years. The Bank paid the Holding Company $600.0 million and $475.0 million in dividends during the years ended December 31, 2023, and 2022, respectively, for which no express approval from the OCC was required. Cash Restrictions The Bank is required under Federal Reserve regulations to maintain cash reserve balances in the form of vault cash or deposits held at a FRB to ensure that it is able to meet customer demands. The reserve requirement ratio is subject to adjustment as economic conditions warrant. Effective March 26, 2020, the Federal Reserve reset the requirement to zero in order to address liquidity concerns resulting from the COVID-19 pandemic. Pursuant to this action, the Bank has not been required to hold cash reserve balances since that date.

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share The following table summarizes the calculation of basic and diluted earnings per common share: Years ended December 31, (In thousands, except per share data) 2023 2022 2021 Net income $ 867,840 $ 644,283 $ 408,864 Less: Preferred stock dividends 16,650 15,919 7,875 Net income available to common stockholders 851,190 628,364 400,989 Less: Earnings allocated to participating securities 7,922 5,672 2,302 Earnings applicable to common stockholders $ 843,268 $ 622,692 $ 398,687 Weighted-average common shares outstanding - basic 171,775 167,452 89,983 Add: Effect of dilutive stock options and restricted stock 108 95 223 Weighted-average common shares outstanding - diluted 171,883 167,547 90,206 Basic earnings per common share $ 4.91 $ 3.72 $ 4.43 Diluted earnings per common share 4.91 3.72 4.42 Earnings per common share is calculated under the two-class method in which all earnings (distributed and undistributed) are allocated to common stock and participating securities based on their respective rights to receive dividends. The Company may grant restricted stock, restricted stock units, non-qualified stock options, incentive stock options, or stock appreciation rights to certain employees and directors under its stock-based compensation programs, which entitle recipients to receive non-forfeitable dividends during the vesting period on a basis equivalent to the dividends paid to holders of common stock. These unvested awards meet the definition of participating securities.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The determination of fair value may require the use of estimates when quoted market prices are not available. Fair value estimates made at a specific point in time are based on management’s judgments regarding future expected losses, current economic conditions, the risk characteristics of each financial instrument, and other subjective factors that cannot be determined with precision. The framework for measuring fair value provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The three levels within the fair value hierarchy are as follows: • Level 1: Inputs to the valuation methodology are unadjusted quoted prices for identical assets or liabilities in active markets that the Company has the ability to access at the measurement date. • Level 2: Inputs to the valuation methodology include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in inactive markets, inputs other than quoted prices that are observable for the asset or liability (i.e., interest rates, rate volatility, prepayment speeds, and credit ratings), or inputs that are derived principally from or corroborated by market data, correlation or other means. • Level 3: Inputs to the valuation methodology are unobservable and significant to the fair value measurement. This includes certain pricing models or other similar techniques that require significant management judgment or estimation. Assets and Liabilities Measured at Fair Value on a Recurring Basis Available-for-Sale Securities. When unadjusted quoted prices are available in an active market, the Company classifies its available-for-sale investment securities within Level 1 of the fair value hierarchy. U.S. Treasury notes have a readily determinable fair value, and therefore, are classified within Level 1 of the fair value hierarchy. When quoted market prices are not available, the Company employs an independent pricing service that utilizes matrix pricing to calculate fair value. These fair value measurements consider observable data, such as dealer quotes, market spreads, cash flows, yield curves, live trading levels, trade execution data, market consensus prepayments speeds, credit information, and the respective terms and conditions for debt instruments. Management maintains procedures to monitor the pricing service's results and has a process in place to challenge their valuations and methodologies. Government agency debentures, Municipal bonds and notes, Agency CMO, Agency MBS, Agency CMBS, CMBS, CLO, Corporate debt, Private label MBS, and Other available-for-sale securities are classified within Level 2 of the fair value hierarchy. Derivative Instruments. The fair values presented for derivative instruments include any accrued interest. Foreign exchange contracts are valued based on unadjusted quoted prices in active markets and accordingly are classified within Level 1 of the fair value hierarchy. Except for mortgage banking derivatives, all other derivative instruments are valued using third-party valuation software, which considers the present value of cash flows discounted using observable forward rate assumptions. The resulting fair value is then validated against valuations performed by dealer counterparties. These derivative instruments are classified within Level 2 of the fair value hierarchy. Mortgage Banking Derivatives. The Company uses forward sales of mortgage loans and mortgage-backed securities to manage the risk of loss associated with its mortgage loan commitments and mortgage loans held for sale. Prior to closing and funding certain single-family residential mortgage loans, an interest rate lock commitment is generally extended to the borrower. During this in-between time period, the Company is subject to the risk that market interest rates may change. If rates rise, investors generally will pay less to purchase mortgage loans, which would result in a reduction in the gain on sale of the loans, or possibly a loss. In an effort to mitigate this risk, forward delivery sales commitments are established in which the Company agrees to either deliver whole mortgage loans to various investors or issue mortgage-backed securities. The fair value of mortgage banking derivatives is determined based on current market prices for similar assets in the secondary market. Accordingly, mortgage banking derivatives are classified within Level 2 of the fair value hierarchy. Originated Loans Held For Sale . The Company has elected to measure originated loans held for sale at fair value under the fair value option per ASC Topic 825, Financial Instruments. Electing to measure originated loans held for sale at fair value reduces certain timing differences and better reflects the price the Company would expect to receive from the sale of these loans. The fair value of originated loans held for sale is based on quoted market prices of similar loans sold in conjunction with securitization transactions. Accordingly, originated loans held for sale are classified within Level 2 of the fair value hierarchy. The following table compares the fair value to the unpaid principal balance of originated loans held for sale: At December 31, 2023 2022 (In thousands) Fair Value Unpaid Principal Balance Difference Fair Value Unpaid Principal Balance Difference Originated loans held for sale $ 2,610 $ 2,658 $ (48) $ 1,991 $ 1,631 $ 360 Rabbi Trust Investments. Investments held in each of the Company's Rabbi Trusts consist primarily of mutual funds that invest in equity and fixed income securities. Shares of these mutual funds are valued based on the NAV as reported by the trustee of the funds, which represents quoted prices in active markets. Accordingly, the Rabbi Trusts' investments are classified within Level 1 of the fair value hierarchy. At December 31, 2023, and 2022, the total cost basis of the investments held in the Rabbi Trusts was $9.2 million and $10.0 million, respectively. Alternative Investments. Equity investments have a readily determinable fair value when unadjusted quoted prices are available in an active market for identical assets. Accordingly, these alternative investments are classified within Level 1 of the fair value hierarchy. At December 31, 2023, and 2022, equity investments with a readily determinable fair value had a total carrying amount of $0.9 million and $0.4 million, respectively, with no remaining unfunded commitment. During the year ended December 31, 2023, there were total write-ups in fair value of $0.5 million associated with these alternative investments. Equity investments that do not have a readily determinable fair value may qualify for the NAV practical expedient if they meet certain requirements. The Company's alternative investments measured at NAV consist of investments in non-public entities that cannot be redeemed since investments are distributed as the underlying equity is liquidated. Alternative investments measured at NAV are not classified within the fair value hierarchy. At December 31, 2023, and 2022, these alternative investments had a total carrying amount of $35.9 million and $89.2 million, respectively, and a remaining unfunded commitment of $29.8 million and $82.7 million, respectively. Contingent Consideration. The Company recorded $16.0 million of contingent consideration at fair value related to two earn-out agreements associated with the acquisition of interLINK on January 11, 2023. The terms of the purchase agreement specified that the seller would receive earn-outs based on the ability of the Company to: (i) re-sign the existing broker dealers under contract, and (ii) generate $2.5 billion in new broker dealer deposit programs within three years of the acquisition date. The estimated fair values of the contingent consideration liabilities are measured on a recurring basis and determined using an income approach considering management’s evaluation of the probability of achievement, forecasted achievement date (payment term), and a discount rate equivalent to the counterparty cost of debt. These significant inputs, which are the responsibility of management and calculated with the assistance of a third-party valuation specialist, are not observable, and accordingly, are classified within Level 3 of the fair value hierarchy. The following table summarizes the unobservable inputs used to derive the estimated fair value of the Company’s contingent consideration liabilities at December 31, 2023 (dollars in thousands): Agreement Maximum Amount Probability of Achievement Payment Term Discount Rate Fair Value (i) Re-sign broker dealers $ 4,826 99.0 % 1.88 6.40 % $ 4,232 (ii) Deposit program growth $ 12,500 100.0 % 1.00 6.40 % $ 11,568 Contingent consideration liabilities are included within Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets. Any fair value adjustments to contingent consideration liabilities are included in Other expense on the accompanying Consolidated Statements of Income. The following table summarizes the fair values of assets and liabilities measured at fair value on a recurring basis: At December 31, 2023 (In thousands) Level 1 Level 2 Level 3 Total Financial Assets: Available-for-sale securities: Government agency debentures $ — $ 264,633 $ — $ 264,633 Municipal bonds and notes — 1,573,233 — 1,573,233 Agency CMO — 48,941 — 48,941 Agency MBS — 3,347,098 — 3,347,098 Agency CMBS — 2,288,071 — 2,288,071 CMBS — 763,749 — 763,749 Corporate debt — 622,155 — 622,155 Private label MBS — 42,808 — 42,808 Other — 9,041 — 9,041 Total available-for-sale securities — 8,959,729 — 8,959,729 Gross derivative instruments, before netting (1) 217 330,419 — 330,636 Originated loans held for sale — 2,610 — 2,610 Investments held in Rabbi Trusts 11,900 — — 11,900 Alternative investments 959 — — 959 Alternative investments measured at NAV (2) — — — 35,888 Total financial assets $ 13,076 $ 9,292,758 $ — $ 9,341,722 Financial Liabilities: Gross derivative instruments, before netting (1) $ 970 $ 334,840 $ — $ 335,810 Contingent consideration — — 15,800 15,800 Total financial liabilities $ 970 $ 334,840 $ 15,800 $ 351,610 At December 31, 2022 (In thousands) Level 1 Level 2 Level 3 Total Financial Assets: Available-for-sale investment securities: U.S. Treasury notes $ 717,040 $ — $ — $ 717,040 Government agency debentures — 258,374 — 258,374 Municipal bonds and notes — 1,633,202 — 1,633,202 Agency CMO — 59,965 — 59,965 Agency MBS — 2,158,024 — 2,158,024 Agency CMBS — 1,406,486 — 1,406,486 CMBS — 896,640 — 896,640 CLO — 2,107 — 2,107 Corporate debt — 704,412 — 704,412 Private label MBS — 44,249 — 44,249 Other — 12,198 — 12,198 Total available-for-sale securities 717,040 7,175,657 — 7,892,697 Gross derivative instruments, before netting (1) 79 222,827 — 222,906 Originated loans held for sale — 1,991 — 1,991 Investments held in Rabbi Trust 12,103 — — 12,103 Alternative investments 430 — — 430 Alternative investments measured at NAV (2) — — — 89,248 Total financial assets $ 729,652 $ 7,400,475 $ — $ 8,219,375 Financial Liabilities: Gross derivative instruments, before netting (1) $ 843 $ 413,656 $ — $ 414,499 (1) Additional information regarding the impact of netting derivative assets and derivative liabilities, as well as the impact from offsetting cash collateral paid to the same derivative counterparties, can be found within Note 17: Derivative Financial Instruments. (2) Certain alternative investments are recorded at NAV. Assets measured at NAV are not classified within the fair value hierarchy. Assets Measured at Fair Value on a Non-Recurring Basis The Company measures certain assets at fair value on a non-recurring basis. The following is a description of valuation methodologies used for assets measured at fair value on a non-recurring basis. Alternative Investments. The measurement alternative has been elected for alternative investments without readily determinable fair values that do not qualify for the NAV practical expedient. The measurement alternative requires investments to be measured at cost minus impairment, if any, plus or minus adjustments resulting from observable price changes in orderly transactions for an identical or similar investment of the same issuer. Accordingly, these alternative investments are classified within Level 2 of the fair value hierarchy. At December 31, 2023, and 2022, the carrying amount of these alternative investments was $53.1 million and $42.8 million, respectively, of which $7.9 million and $5.9 million, respectively, were considered to be measured at fair value. During the year ended December 31, 2023, there were $1.8 million of total net write-ups due to observable price changes and $1.0 million of total write-downs due to impairment. Loans Transferred to Held for Sale. Once a decision has been made to sell loans not previously classified as held for sale, these loans are transferred into the held for sale category and carried at the lower of cost or fair value, less estimated costs to sell. At the time of transfer into held for sale classification, any amount by which cost exceeds fair value is accounted for as a valuation allowance. This activity generally pertains to loans with observable inputs, and therefore, are classified within Level 2 of the fair value hierarchy. However, should these loans include adjustments for changes in loan characteristics based on unobservable inputs, the loans would then be classified within Level 3 of the fair value hierarchy. At December 31, 2023, and 2022, there were $3.9 million and zero loans transferred to held for sale on the accompanying Consolidated Balance Sheets, respectively. Collateral Dependent Loans and Leases. Loans and leases for which repayment is substantially expected to be provided through the operation or sale of collateral are considered collateral dependent, and are valued based on the estimated fair value of the collateral, less estimated costs to sell at the reporting date, using customized discounting criteria. Accordingly, collateral dependent loans and leases are classified within Level 3 of the fair value hierarchy. Other Real Estate Owned and Repossessed Assets. OREO and repossessed assets are held at the lower of cost or fair value and are considered to be measured at fair value when recorded below cost. The fair value of OREO is calculated using independent appraisals or internal valuation methods, less estimated selling costs, and may consider available pricing guides, auction results, and price opinions. Certain repossessed assets may also require assumptions about factors that are not observable in an active market when determining fair value. Accordingly, OREO and repossessed assets are classified within Level 3 of the fair value hierarchy. At December 31, 2023, and 2022, the total carrying value of OREO and repossessed assets was $9.1 million and $2.3 million, respectively. In addition, the amortized cost of consumer loans secured by residential real estate property that are in the process of foreclosure at December 31, 2023, was $8.7 million. Estimated Fair Values of Financial Instruments and Mortgage Servicing Assets The Company is required to disclose the estimated fair values of certain financial instruments and mortgage servicing rights. The following is a description of the valuation methodologies used to estimate fair value for those assets and liabilities. Cash and Cash Equivalents . Given the short time frame to maturity, the carrying amount of cash and cash equivalents, which comprises cash and due from banks and interest-bearing deposits, approximates fair value. Cash and cash equivalents are classified within Level 1 of the fair value hierarchy. Held-to-Maturity Securities . When quoted market prices are not available, the Company employs an independent pricing service that utilizes matrix pricing to calculate fair value. These fair value measurements consider observable data, such as dealer quotes, market spreads, cash flows, yield curves, live trading levels, trade execution data, market consensus prepayments speeds, credit information, and the respective terms and conditions for debt instruments. Management maintains procedures to monitor the pricing service's results and has a process in place to challenge their valuations and methodologies. Held-to-maturity securities, which include Agency CMO, Agency MBS, Agency CMBS, Municipal bonds and notes, and CMBS, are classified within Level 2 of the fair value hierarchy. Loans and Leases, net . Except for collateral dependent loans and leases, the fair value of loans and leases held for investment is estimated using a discounted cash flow methodology, based on future prepayments and market interest rates inclusive of an illiquidity discount for comparable loans and leases. The associated cash flows are then adjusted for associated credit risks and other potential losses, as appropriate. Loans and leases are classified within Level 3 of the fair value hierarchy. Mortgage Servicing Rights . Mortgage servicing rights are initially measured at fair value and subsequently measured using the amortization method. The Company assesses mortgage servicing rights for impairment each quarter and establishes or adjusts the valuation allowance to the extent that amortized cost exceeds the estimated fair market value. Fair value is calculated as the present value of estimated future net servicing income and relies on market based assumptions for loan prepayment speeds, servicing costs, discount rates, and other economic factors. Accordingly, the primary risk inherent in valuing mortgage servicing rights is the impact of fluctuating interest rates on the related servicing revenue stream. Mortgage servicing rights are classified within Level 3 of the fair value hierarchy. Deposit Liabilities . The fair value of deposit liabilities, which comprises demand deposits, interest-bearing checking, savings, health savings, and money market accounts, reflects the amount payable on demand at the reporting date. Deposit liabilities are classified within Level 2 of the fair value hierarchy. Time Deposits . The fair value of fixed-maturity certificates of deposit is estimated using rates that are currently offered for deposits with similar remaining maturities. Time deposits are classified within Level 2 of the fair value hierarchy. Securities Sold Under Agreements to Repurchase and Other Borrowings . The fair value of securities sold under agreements to repurchase and other borrowings that mature within 90 days approximates their carrying value. The fair value of securities sold under agreements to repurchase and other borrowings that mature after 90 days is estimated using a discounted cash flow methodology based on current market rates and adjusted for associated credit risks, as appropriate. Securities sold under agreements to repurchase and other borrowings are classified within Level 2 of the fair value hierarchy. Federal Home Loan Bank Advances and Long-Term Debt . The fair value of FHLB advances and long-term debt is estimated using a discounted cash flow methodology in which discount rates are matched with the time period of the expected cash flows and adjusted for associated credit risks, as appropriate. FHLB advances and long-term debt are classified within Level 2 of the fair value hierarchy. The following table summarizes the carrying amounts, estimated fair values, and classifications within the fair value hierarchy of selected financial instruments and mortgage servicing rights: At December 31, 2023 2022 (In thousands) Carrying Fair Carrying Fair Assets: Level 1 Cash and cash equivalents $ 1,715,795 $ 1,715,795 $ 839,943 $ 839,943 Level 2 Held-to-maturity investment securities 7,074,588 6,264,623 6,564,697 5,761,453 Level 3 Loans and leases, net 50,090,315 48,048,106 49,169,685 47,604,463 Mortgage servicing rights 8,523 24,495 9,515 27,043 Liabilities: Level 2 Deposit liabilities $ 52,319,825 $ 52,319,825 $ 49,893,391 $ 49,893,391 Time deposits 8,464,459 8,426,708 4,160,949 4,091,979 Securities sold under agreements to repurchase and other borrowings 458,387 458,380 1,151,830 1,151,797 FHLB advances 2,360,018 2,358,381 5,460,552 5,459,218 Long-term debt (1) 1,048,820 999,918 1,073,128 1,001,779 (1)

Retirement Benefit Plans

Retirement Benefit Plans	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Retirement Benefit Plans	Retirement Benefit Plans Defined Benefit Pension and Postretirement Benefit Plans The Bank had offered a qualified noncontributory defined benefit Pension Plan and a non-qualified SERP to eligible employees and key executives who met certain age and service requirements, both of which were frozen effective December 31, 2007. Only those employees who were hired prior to January 1, 2007, and who became participants of the plans prior to January 1, 2008, have accrued benefits under the plans. The Bank also provides for OPEB to certain retired employees. In connection with the merger with Sterling, on January 31, 2022, the Company assumed the benefit obligations of Sterling's non-qualified SERP and OPEB plans, which included the Astoria Bank Excess Benefit and Supplemental Benefit Plans, Astoria Bank Directors' Retirement Plan, Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors, Supplemental Executive Retirement Plan of Provident Bank, Supplemental Executive Retirement Plan of Provident Bank - Other, Sterling Bancorp Supplemental Postretirement Life Insurance Plan, Astoria Bank Postretirement Welfare Benefit Plans, and a Split Dollar Life Insurance Arrangement. Each of the plan's measurement dates, including the plans assumed from Sterling in the merger, coincides with the Company's December 31 year end. The following table summarizes the changes in the benefit obligation, fair value of plan assets, and funded status of the defined benefit pension and postretirement benefit plans at December 31: Pension SERP OPEB (In thousands) 2023 2022 2023 2022 2023 2022 Change in benefit obligation: Beginning balance $ 187,836 $ 250,263 $ 4,245 $ 1,873 $ 22,822 $ 1,904 Benefit obligation assumed from Sterling — — — 4,517 — 26,030 Service cost — — — — 27 34 Interest cost 8,782 5,565 191 107 1,042 652 Actuarial (gain) loss 3,333 (57,751) 183 (581) (382) (4,992) Benefits paid (9,965) (10,241) (480) (1,671) (840) (806) Ending balance 189,986 187,836 4,139 4,245 22,669 22,822 Change in plan assets: Beginning balance 201,382 271,846 — — — — Actual return on plan assets 25,750 (60,223) — — — — Employer contributions — — 480 1,671 840 806 Benefits paid (9,965) (10,241) (480) (1,671) (840) (806) Ending balance 217,167 201,382 — — — — Funded status (1) $ 27,181 $ 13,546 $ (4,139) $ (4,245) $ (22,669) $ (22,822) (1) The overfunded (underfunded) status of each plan is respectively included in Accrued interest receivable and other assets or Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets, as applicable. The following table summarizes the weighted-average assumptions used to determine the benefit obligation at December 31: Discount Rate 2023 2022 Pension: Webster Bank Pension Plan 4.76 % 4.96 % SERP: Webster Bank Supplemental Defined Benefit Plan for Executive Officers 4.68 % 4.88 % Astoria Bank Excess Benefit and Supplemental Benefit Plans 4.56 4.77 Astoria Bank Directors' Retirement Plan 4.50 4.70 Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors 4.50 4.70 Supplemental Executive Retirement Plan of Provident Bank 4.83 5.04 Supplemental Executive Retirement Plan of Provident Bank - Other 4.71 4.90 OPEB: Webster Bank Postretirement Medical Benefit Plan 4.54 % 4.72 % Sterling Bancorp Supplemental Postretirement Life Insurance Plan 4.51 4.70 Astoria Bank Postretirement Welfare Benefit Plans 4.74 4.94 Split Dollar Life Insurance Arrangement 4.45 4.63 The following table summarizes the amounts recorded in accumulated other comprehensive (loss) income that have not yet been recognized in net periodic benefit cost (income) at December 31: Pension SERP OPEB (In thousands) 2023 2022 2023 2022 2023 2022 Net actuarial loss (gain) $ 41,296 $ 56,717 $ 312 $ 50 $ (3,231) $ (5,573) Deferred tax (benefit) expense (11,201) (15,383) (85) (14) 876 1,512 Net amount recorded in (AOCL) $ 30,095 $ 41,334 $ 227 $ 36 $ (2,355) $ (4,061) The following table summarizes the components of net periodic benefit cost (income) for the years ended December 31: Pension SERP OPEB (In thousands) 2023 2022 2021 2023 2022 2021 2023 2022 2021 Service cost $ — $ — $ — $ — $ — $ — $ 27 $ 34 $ — Interest cost 8,782 5,565 4,663 191 107 30 1,042 652 19 Expected return on plan assets (11,778) (14,675) (14,385) — — — — — — Amortization of actuarial loss (gain) 4,781 2,224 4,102 6 26 38 (2,704) (40) (38) Net periodic benefit cost (income) (1) $ 1,785 $ (6,886) $ (5,620) $ 197 $ 133 $ 68 $ (1,635) $ 646 $ (19) (1) Net periodic benefit cost (income) is included in Other expense on the accompanying Consolidated Statements of Income. The following table summarizes the weighted-average assumptions used to determine net periodic benefit cost (income) for the years ended December 31: Discount Rate 2023 2022 2021 Pension: Webster Bank Pension Plan 4.96 % 2.65 % 2.29 % SERP: Webster Bank Supplemental Defined Benefit Plan for Executive Officers 4.88 % 2.45 % 1.91 % Astoria Bank Excess Benefit and Supplemental Benefit Plans 4.77 2.58 n/a Astoria Bank Directors' Retirement Plan 4.70 2.23 n/a Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors 4.70 2.37 n/a Supplemental Executive Retirement Plan of Provident Bank 5.04 2.76 n/a Supplemental Executive Retirement Plan of Provident Bank - Other 4.90 2.38 n/a OPEB: Webster Bank Postretirement Medical Benefit Plan 4.72 % 1.99 % 1.40 % Sterling Bancorp Supplemental Postretirement Life Insurance Plan 4.70 2.35 n/a Astoria Bank Postretirement Welfare Benefit Plans 4.94 2.93 n/a Split Dollar Life Insurance Arrangement 4.63 2.20 n/a Expected Long-Term Rate of Return on Plan Assets 2023 2022 2021 Pension: Webster Bank Pension Plan 6.00 % 5.50 % 5.50 % Assumed Health Care Cost Trend Rate (1) 2023 2022 2021 OPEB: Webster Bank Postretirement Medical Benefit Plan 6.50 % 6.25 % 6.50 % Astoria Bank Postretirement Welfare Benefit Plans 6.40 6.60 n/a (1) The rates to which the healthcare cost trend rates are assumed to decline (ultimate trend rates) along with the year that the ultimate trend rates will be reached for the Webster Bank Postretirement Medical Benefit Plan and the Astoria Bank Postretirement Welfare Benefit Plans are 4.40% in 2032, and 4.50% in 2033, respectively. The discount rates used to determine the benefit obligation and net periodic benefit cost (income) for the Company's defined benefit pension and postretirement benefit plans were generally selected by reference to a high-quality bond yield curve, using a full yield curve approach, and matched to the timing and amount of each plan's expected benefit payments. The following table summarizes amounts recognized in other comprehensive (loss) income, including reclassification adjustments, for the years ended December 31: Pension SERP OPEB (In thousands) 2023 2022 2021 2023 2022 2021 2023 2022 2021 Net actuarial (gain) loss $ (10,639) $ 17,148 $ (12,008) $ 183 $ (581) $ (77) $ (382) $ (4,992) $ 33 Amounts reclassified from (4,781) (2,224) (4,102) (6) (26) (38) 2,704 40 38 Total (gain) loss recognized in $ (15,420) $ 14,924 $ (16,110) $ 177 $ (607) $ (115) $ 2,322 $ (4,952) $ 71 At December 31, 2023, the expected future benefit payments for the Company's defined benefit pension and postretirement benefits plans are as follows: (In thousands) Pension SERP OPEB 2024 $ 10,634 $ 489 $ 2,926 2025 11,038 473 2,789 2026 11,429 455 2,552 2027 11,864 433 2,339 2028 12,246 409 2,083 Thereafter 64,148 1,646 7,393 Asset Management The Pension Plan invests primarily in common collective trusts and registered investment companies. However, the Pension Plan's investment policy guidelines also allow for the investment in cash and cash equivalents, fixed income securities, and equity securities. Common collective trusts and registered investment companies are both benchmarked against the Standard & Poor's 500 Index. Incremental benchmarks used to assess the common collective trusts include the S&P 400 Mid Cap Index, Russell 200 Index, MSCI ACWI ex U.S. Index, and the Barclay's Capital U.S. Long Credit Index. The standard deviation should not exceed that of the composite index. The Pension Plan's investment strategy and asset allocations are monitored by the Company's Retirement Plans Committee with the assistance of external investment advisors, and the investment portfolio is rebalanced, as appropriate. The target asset allocation percentages for the year ended December 31, 2023, were 64.5% The overall investment objective of the Pension Plan is to maintain a diversified portfolio with a targeted expected long-term rate of return on plan assets of approximately 6.00%. The expected long-term rate of return on plans assets is the average rate of return expected to be realized on funds invested, or expected to be invested, to provide for the benefits included in the benefit obligation. The expected long-term rate of return on plans assets is generally established as of the beginning of the year based upon historical and projected returns for each asset category, with subsequent remeasurements occurring in interim periods, as appropriate. Depending on market conditions, the expected long-term rate of return on plan assets may exceed or fall short of the targeted percentage. Fair Value Measurement The following is a description of the valuation methodologies used for the Pension Plan's assets measured at fair value: Common Collective Trusts. Common collective trusts are valued based on the NAV as reported by the trustee of the funds. The funds' underlying investments, which primarily comprise fixed-income debt securities and open-end mutual funds, are valued using quoted market prices in active markets or unobservable inputs for similar assets. Therefore, common collective trusts are classified as Level 2 within the fair value hierarchy. Transactions may occur daily within a trust. If a full redemption of the trust were to be initiated, the investment advisor reserves the right to temporarily delay withdrawals from the trust in order to ensure that the liquidation of securities is carried out in an orderly business manner. Registered Investment Companies. Registered investment companies are valued at the daily closing price as reported by the funds. Registered investment companies held by the Pension Plan are quoted in an active market and are classified as Level 1 within the fair value hierarchy. Cash and Cash Equivalents. Cash and cash equivalents are recorded at cost plus accrued interest, which approximates fair value given the short time frame to maturity, and are classified as Level 1 within the fair value hierarchy. The following table sets forth by level within the fair value hierarchy the Pension Plan's assets at fair value: At December 31, 2023 2022 (In thousands) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Common collective trusts $ — $ 195,004 $ — $ 195,004 $ — $ 172,941 $ — $ 172,941 Registered investment companies 20,965 — — 20,965 26,923 — — 26,923 Cash and cash equivalents 1,198 — — 1,198 1,518 — — 1,518 Total pension plan assets $ 22,163 $ 195,004 $ — $ 217,167 $ 28,441 $ 172,941 $ — $ 201,382 Multiple-Employer Defined Benefit Pension Plan The Bank participates in a multi-employer plan that provides pension benefits to former employees of a bank acquired by the Company. Participation in the plan was frozen as of September 1, 2004. The plan maintains a single trust and does not segregate the assets or liabilities of its participating employers. Minimum required employer contributions are determined by an independent actuary and are calculated using a 15-year shortfall amortization factor. There are no collective bargaining agreements or other obligations requiring contributions to the plan, nor has a funding improvement plan been implemented. The following table summarizes information related to the Bank's participation in the multi-employer plan: (In thousands) Contributions Funded Status Plan Name Employer Identification Number Plan Number Surcharge Imposed 2023 2022 2021 2023 2022 Pentegra Defined Benefit Plan 13-5645888 333 No $448 $448 $692 At least 80 percent At least 80 percent The Bank's contributions to the multi-employer plan for the years ended December 31, 2023, 2022, and 2021, did not exceed more than 5% of total plan contributions for the plan years ended June 30, 2022, 2021, and 2020. The plan's Form 5500 was not available for the plan year ended June 30, 2023, as of the date the Company's Consolidated Financial Statements were issued. As of July 1, 2023, the date of the most recent actuarial valuation, the plan administrator confirmed that the Bank’s portion of the multi-employer plan was $3.1 million underfunded. Defined Contribution Postretirement Benefit Plans The Bank also sponsors defined contribution postretirement benefit plans established under Section 401(k) of the Internal Revenue Code: Webster Bank Retirement Savings Plan. Employees who have attained age 21 may elect to contribute up to 75% of their eligible compensation on either a pre-tax or post-tax basis. The Bank makes matching contributions equal to 100% of the first 2% and 50% of the next 6% of employees contributions after employees have completed one year of eligible service. If an employee fails to enroll in the plan within 90 days of hire, the employee will be automatically enrolled on a pre-tax basis with a deferral rate set at 3% of eligible compensation. As of December 31, 2023, individuals who became employees of the Company as a result of the merger with Sterling were not eligible to participate in the plan. Sterling National Bank 401k and Profit Sharing Plan. Eligible legacy Sterling employees as January 31, 2022, who are now employees of the Company may elect to contribute up to 50% of their eligible compensation on either a pre-tax or post-tax basis. The Bank makes matching contributions equal to 50% of employee contributions up to 4% of eligible compensation, for a maximum match of 2%, and a profit sharing contribution equal to 3% of eligible compensation for all eligible legacy Sterling employees, regardless of whether they had contributed to the plan in the current year. The plan also includes an automatic employee deferral increase provision, whereby deferral contributions for participants who had been automatically enrolled in the plan will increase by 1% every January 1 up to 10%. Compensation and benefits expense included total employer contributions under the plans of $20.3 million, $18.2 million, and $13.1 million for the years ended December 31, 2023, 2022, and 2021, respectively.

Share-Based Plans

Share-Based Plans	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Share-Based Plans	Share-Based Plans The Company maintains a stock compensation plan that provides for the grant of stock options, stock appreciation rights, restricted stock, performance-based stock, and stock units to better align the interests of its employees and directors with those of its stockholders. The total number of shares of Webster common stock authorized for issuance under the plan is 21.4 million shares. At December 31, 2023, there were 4.5 million shares available to be granted. Stock compensation expense is recognized over the required service vesting period for each award based on the grant-date fair value and is included in Compensation and benefits on the accompanying Consolidated Statements of Income. The following table summarizes stock-based compensation plan activity for the year ended December 31, 2023: Non-Vested Restricted Stock Awards Outstanding Stock Options Outstanding Time-Based Performance-Based Number of Weighted-Average Number of Weighted-Average Number of Weighted-Average Balance, beginning of period 1,479,742 $ 50.47 310,374 $ 57.65 88,229 $ 23.76 Granted 937,735 51.35 286,161 48.86 — — Vested (740,748) 48.88 (60,988) 60.24 — — Forfeited (77,310) 51.62 (15,544) 55.54 — — Exercised — — — — (77,257) 23.00 Balance, end of period 1,599,419 52.72 520,003 52.58 10,972 29.14 Restricted Stock Awards Time-based restricted stock awards vest over the applicable service period ranging from one Performance-based restricted stock awards generally vest after a three year performance period, with the total share quantity dependent on the Company meeting certain target performance conditions throughout the vesting period, ranging from 0% to 150%. Under the plan, 50% of the share quantity is determined based on total stockholder return as compared to the Company's compensation peer group, while the other 50% is based on the Company's average return on equity. The fair value of performance-based restricted stock awards used to determine compensation expense is calculated using the Monte-Carlo simulation model for total stockholder return awards and the closing price of Webster common stock at the grant date for For the years ended December 31, 2023, 2022, and 2021, the Company recognized restricted stock compensation expense totaling $54.5 million, $55.1 million, and $13.7 million, respectively. The corresponding income tax benefit recognized was $13.9 million, $12.0 million, and $5.4 million, respectively. The fair value of restricted stock awards that had vested during the years ended December 31, 2023, 2022, and 2021, was $39.9 million, $51.7 million, and $12.5 million, respectively. At December 31, 2023, there was $40.0 million of unrecognized restricted stock expense related to non-vested restricted stock awards, which is expected to be recognized over a weighted-average period of 1.7 years. Stock Options Stock options are granted at an exercise price equal to the market value of Webster common stock on the grant date. Each stock option grants the holder the right to acquire one share of Webster common stock over a contractual life of ten years. The Company has not granted stock options since 2013. At December 31, 2023, there were 10,278 and 694 incentive and Total pre-tax intrinsic value, or the difference between the Webster common stock closing price on the last trading day of the year and the weighted-average exercise price multiplied by the number of shares, represents the aggregate intrinsic value that would have been received by the option holders had all of their outstanding options been exercised on December 31, 2023. At December 31, 2023, the total pre-tax intrinsic value was $0.2 million. For the years ended December 31, 2023, 2022, and 2021, the total intrinsic value of the options exercised was $2.2 million, $1.0 million, and $9.0 million, respectively. The amount of cash received from the exercise of stock options during the years ended December 31, 2023, 2022, and 2021, was $1.8 million, $0.7 million, and $7.1 million, respectively.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting The Company’s operations are organized into three reportable segments that represent its primary businesses: Commercial Banking, HSA Bank, and Consumer Banking. These segments reflect how executive management responsibilities are assigned, how discrete financial information is evaluated, the type of customer served, and how products and services are provided. Certain Treasury activities, including the operations of interLINK, along with the amounts required to reconcile profitability metrics to those reported in accordance with GAAP, are included in the Corporate and Reconciling category. In connection with the acquisition of interLINK on January 11, 2023, the $143.2 million of goodwill recorded was allocated entirely to Commercial Banking. In addition, as previously discussed in Note 2: Mergers and Acquisitions and Note 8: Goodwill and Other Intangible Assets, the allocation of the purchase price for both the Sterling merger and Bend acquisition was final as of March 31, 2023. As a result, of the total $1.9 billion in goodwill recorded in connection with the Sterling merger, $1.7 billion and $0.2 billion was allocated to Commercial Banking and Consumer Banking, respectively. The $35.7 million of goodwill recorded in connection with the Bend acquisition was allocated entirely to HSA Bank. Segment Reporting Methodology The Company uses an internal profitability reporting system to generate information by reportable segment, which is based on a series of management estimates for FTP, and allocations for non-interest expense, provision for credit losses, income taxes, and equity capital. These estimates and allocations, certain of which are subjective in nature, are periodically reviewed and refined. Changes in estimates and allocations that affect the results of any reportable segment do not affect the consolidated financial position or results of operations of the Company as a whole. The full profitability measurement reports, which are prepared for each reportable segment, reflect non-GAAP reporting methodologies. The differences between full profitability and GAAP results are reconciled in the Corporate and Reconciling category. The Company allocates interest income and interest expense to each business through an internal matched maturity FTP process. The goal of the FTP allocation is to encourage loan and deposit growth consistent with the Company’s overall profitability objectives. The FTP process considers the specific interest rate risk and liquidity risk of financial instruments and other assets and liabilities in each line of business. Loans are assigned an FTP rate for funds used and deposits are assigned an FTP rate for funds provided. The allocation considers the origination date and the earlier of the maturity date or the repricing date of a financial instrument to assign an FTP rate for loans and deposits originated each day. The FTP process transfers the corporate interest rate risk exposure to the Treasury function included within the Corporate and Reconciling category where such exposures are centrally managed. The Company allocates a majority of non-interest expense to each reportable segment using an activity and driver-based costing process. Costs, including shared services and back-office support areas, are analyzed, pooled by process, and assigned to the appropriate reportable segment. The combination of direct revenue, direct expenses, FTP, and allocations of non-interest expense produces PPNR, which is the basis the segments are reviewed by executive management. The Company also allocates the provision for credit losses to each reportable segment based on management's estimate of the expected loss content in each of the specific loan and lease portfolios. The ACL on loans and leases is included in total assets within the Corporate and Reconciling category. Business development expenses, such as merger-related and strategic initiatives costs, are also generally included in the Corporate and Reconciling category. The following table presents balance sheet information, including the appropriate allocations, for the Company's reportable segments and the Corporate and Reconciling category: At December 31, 2023 (In thousands) Commercial HSA Consumer Corporate and Consolidated Goodwill $ 2,029,204 $ 57,485 $ 544,776 $ — $ 2,631,465 Total assets 43,381,361 122,421 10,789,339 20,652,128 74,945,249 At December 31, 2022 (In thousands) Commercial HSA Consumer Corporate and Consolidated Goodwill $ 1,904,291 $ 57,779 $ 552,034 $ — $ 2,514,104 Total assets 44,380,582 122,729 10,625,334 16,148,876 71,277,521 The following tables present operating results, including the appropriate allocations, for the Company’s reportable segments and the Corporate and Reconciling category: Year ended December 31, 2023 (In thousands) Commercial HSA Consumer Corporate and Consolidated Net interest income $ 1,537,031 $ 302,856 $ 798,483 $ (301,101) $ 2,337,269 Non-interest income 132,660 88,113 107,456 (13,892) 314,337 Non-interest expense 439,290 168,160 425,281 383,624 1,416,355 Pre-tax, pre-provision net revenue 1,230,401 222,809 480,658 (698,617) 1,235,251 Provision for credit losses 131,237 — 11,972 7,538 150,747 Income before income taxes 1,099,164 222,809 468,686 (706,155) 1,084,504 Income tax expense 246,212 58,822 118,108 (206,478) 216,664 Net income $ 852,952 $ 163,987 $ 350,578 $ (499,677) $ 867,840 Year ended December 31, 2022 (In thousands) Commercial HSA Consumer Corporate and Consolidated Net interest income $ 1,346,384 $ 218,149 $ 720,789 $ (251,036) $ 2,034,286 Non-interest income 171,437 104,586 119,691 45,069 440,783 Non-interest expense 398,100 151,329 426,133 420,911 1,396,473 Pre-tax, pre-provision net revenue 1,119,721 171,406 414,347 (626,878) 1,078,596 Provision (benefit) for credit losses 276,550 — (3,754) 7,823 280,619 Income before income taxes 843,171 171,406 418,101 (634,701) 797,977 Income tax expense 207,188 45,937 108,657 (208,088) 153,694 Net income $ 635,983 $ 125,469 $ 309,444 $ (426,613) $ 644,283 Year ended December 31, 2021 (In thousands) Commercial HSA Consumer Corporate and Consolidated Net interest income $ 585,297 $ 168,595 $ 375,318 $ (228,121) $ 901,089 Non-interest income 83,538 102,814 95,887 41,133 323,372 Non-interest expense 192,977 134,258 297,217 120,648 745,100 Pre-tax, pre-provision net revenue 475,858 137,151 173,988 (307,636) 479,361 (Benefit) for credit losses (51,348) — (3,068) (84) (54,500) Income before income taxes 527,206 137,151 177,056 (307,552) 533,861 Income tax expense 134,965 36,619 42,139 (88,726) 124,997 Net income $ 392,241 $ 100,532 $ 134,917 $ (218,826) $ 408,864

Revenue from contracts with Cus

Revenue from contracts with Customers Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	Revenue from Contracts with Customers The following tables summarize revenues recognized in accordance with ASC Topic 606, Revenue from Contracts with Customers. These disaggregated amounts, together with sources of other non-interest income that are subject to other GAAP topics, have been reconciled to non-interest income by reportable segment as presented within Note 21: Segment Reporting. Year ended December 31, 2023 (In thousands) Commercial HSA Consumer Corporate and Consolidated Non-interest Income: Deposit service fees $ 20,527 $ 81,051 $ 66,999 $ 741 $ 169,318 Loan and lease related fees (1) 17,633 — — — 17,633 Wealth and investment services (2) 11,543 — 17,478 (22) 28,999 Other — 7,062 6,199 4,193 17,454 Revenue from contracts with customers 49,703 88,113 90,676 4,912 233,404 Other sources of non-interest income 82,957 — 16,780 (18,804) 80,933 Total non-interest income $ 132,660 $ 88,113 $ 107,456 $ (13,892) $ 314,337 Year ended December 31, 2022 (In thousands) Commercial HSA Consumer Corporate and Consolidated Non-interest Income: Deposit service fees $ 27,663 $ 97,654 $ 71,353 $ 1,802 $ 198,472 Loan and lease related fees (1) 21,498 — — — 21,498 Wealth and investment services 11,350 — 28,957 (30) 40,277 Other — 6,932 1,493 — 8,425 Revenue from contracts with customers 60,511 104,586 101,803 1,772 268,672 Other sources of non-interest income 110,926 — 17,888 43,297 172,111 Total non-interest income $ 171,437 $ 104,586 $ 119,691 $ 45,069 $ 440,783 Year ended December 31, 2021 (In thousands) Commercial HSA Consumer Corporate and Consolidated Non-interest Income: Deposit service fees $ 16,933 $ 94,844 $ 50,561 $ 372 $ 162,710 Wealth and investment services 12,152 — 27,471 (37) 39,586 Other — 7,970 2,140 — 10,110 Revenue from contracts with customers 29,085 102,814 80,172 335 212,406 Other sources of non-interest income 54,453 — 15,715 40,798 110,966 Total non-interest income $ 83,538 $ 102,814 $ 95,887 $ 41,133 $ 323,372 (1) A portion of loan and lease related fees comprises income generated from factored receivables and payroll financing activities that is within the scope of ASC Topic 606. These Commercial Banking revenue streams were new to the Company in 2022 due to the businesses acquired in connection with the Sterling merger. (2) Effective as of the fourth quarter of 2022, the wealth and investment services revenue stream for Consumer Banking was impacted by the restructuring of a process in which the Company offers brokerage, investment advisory, and certain insurance-related services to customers. The staff providing these services, who had previously been employees of the Bank, are now employees of a third-party service provider. As a result, the Company now recognizes income from this program on a net basis, which thereby reduces gross reported wealth and investment services non-interest income and the related compensation and benefits non-interest expense on the accompanying Consolidated Statements of Income. Contracts with customers did not generate significant contract assets and liabilities at December 31, 2023, or 2022. Major Revenue Streams Deposit service fees consist of fees earned from commercial and consumer customer deposit accounts, such as account maintenance and cash management/analysis fees, as well as other transactional service charges (i.e., insufficient funds, wire transfers, stop payment fees, etc.). Performance obligations for account maintenance services and cash management/analysis fees are satisfied on a monthly basis at a fixed transaction price, whereas performance obligations for other deposit service charges that result from various customer-initiated transactions are satisfied at a point-in-time when the service is rendered. Payment for deposit service fees is generally received immediately or in the following month through a direct charge to the customers' accounts. Certain commercial customer contracts include credit clauses, whereby the Company will grant credit upon the customer meeting pre-determined conditions, which can be used to offset fees. On occasion, the Company may also waive certain fees. Fee waivers are recognized as a reduction to revenue in the period the waiver is granted to the customer. The deposit service fees revenue stream also includes interchange fees earned from debit and credit card transactions. The transaction price for interchange services is based on the transaction value and the interchange rate set by the card network. Performance obligations for interchange fees are satisfied at a point-in-time when the cardholders' transaction is authorized and settled. Payment for interchange fees is generally received immediately or in the following month. Factored receivables non-interest income consists of fees earned from accounts receivable management services. The Company factors accounts receivable, with and without recourse, for customers whereby the Company purchases their accounts receivable at a discount and assumes the risk, as applicable, and ownership of the assets through direct cash receipt from the end consumer. Factoring services are performed in exchange for a non-refundable fee at a transaction price based on a percentage of the gross invoice amount of each receivable purchased, subject to a minimum required amount. The performance obligation for factoring services is generally satisfied at a point-in-time when the receivable is assigned to the Company. However, should the commission earned not meet or exceed the minimum required annual amount, the difference between that and the actual amount is recognized at the end of the contract term. Other fees associated with factoring receivables may include wire transfer and technology fees, field examination fees, and Uniform Commercial Code fees, where the performance obligations are satisfied at a point-in-time when the services are rendered. Payment from the customer for factoring services is generally received immediately or within the following month. Payroll finance non-interest income consists of fees earned from performing payroll financing and business process outsourcing services, including full back-office technology and tax accounting services, along with payroll preparation, making payroll tax payments, invoice billings, and collections for independently-owned temporary staffing companies nationwide. Performance obligations for payroll finance and business processing activities are either satisfied upon completion of the support services or as payroll remittances are made on behalf of customers to fund their employee payroll, which generally occurs on a weekly basis. The agreed-upon transaction price is based on a fixed-percentage per the terms of the contract, which could be subject to a hold-back reserve to provide for any balances that are assessed to be at risk of collection. When the Company collects on amounts due from end consumers on behalf of its customers and at the time of financing payroll, the Company retains the agreed-upon transaction price payable for the performance of its services and remits an amount to the customer net of any advances and payroll tax withholdings, as applicable. Wealth and investment services consist of fees earned from asset management, trust administration, and investment advisory services, and through facilitating securities transactions. Performance obligations for asset management and trust administration services are satisfied on a monthly or quarterly basis at a transaction price based on a percentage of the period-end market value of the assets under administration. Payment for asset management and trust administration services is generally received a few days after period-end through a direct charge to the customers' accounts. Performance obligations for investment advisory services are satisfied over the period in which the services are provided through a time-based measurement of progress, and the agreed-upon transaction price with the customer varies depending on the nature of the services performed. Performance obligations for facilitating securities transactions are satisfied at a point-in-time when the securities are sold at a transaction price that is based on a percentage of the contract value. Payment for both investment advisory services and facilitating securities transactions may be received in advance of the service, but generally is received immediately or in the following period, in arrears.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Credit-Related Financial Instruments In the normal course of business, the Company offers financial instruments with off-balance sheet risk to meet the financing needs of its customers. These transactions include commitments to extend credit, standby letters of credit, and commercial letters of credit, which involve, to varying degrees, elements of credit risk. The following table summarizes the outstanding amounts of credit-related financial instruments with off-balance sheet risk: At December 31, (In thousands) 2023 2022 Commitments to extend credit $ 12,026,597 $ 11,237,496 Standby letters of credit 482,462 380,655 Commercial letters of credit 54,382 53,512 Total credit-related financial instruments with off-balance sheet risk $ 12,563,441 $ 11,671,663 The Company enters into contractual commitments to extend credit to its customers (i.e., revolving credit arrangements, term loan commitments, and short-term borrowing agreements), generally with fixed expiration dates or other termination clauses and that require payment of a fee. Substantially all of the Company's commitments to extend credit are contingent upon its customers maintaining specific credit standards at the time of loan funding, and are often secured by real estate collateral. Since the majority of the Company's commitments typically expire without being funded, the total contractual amount does not necessarily represent the Company's future payment requirements. Standby letters of credit are written conditional commitments issued by the Company to guarantee its customers' performance to a third party. In the event the customer does not perform in accordance with the terms of its agreement with a third-party, the Company would be required to fund the commitment. The contractual amount of each standby letter of credit represents the maximum amount of potential future payments the Company could be required to make. Historically, the majority of the Company's standby letters of credit expire without being funded. However, if the commitment were funded, the Company has recourse against the customer. The Company's standby letter of credit agreements are often secured by cash or other collateral. Commercial letters of credit are issued to finance either domestic or foreign customer trade arrangements. As a general rule, drafts are committed to be drawn when the goods underlying the transaction are in transit. Similar to standby letters of credit, the Company's commercial letter of credit agreements are often secured by the underlying goods subject to trade. Allowance for Credit Losses on Unfunded Loan Commitments An ACL is recorded under the CECL methodology and included in Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets to provide for the unused portion of commitments to lend that are not unconditionally cancellable by the Company. At December 31, 2023, and 2022, the ACL on unfunded loan commitments totaled $24.7 million and $27.7 million, respectively. Litigation The Company is subject to certain legal proceedings and unasserted claims and assessments in the ordinary course of business. Legal contingencies are evaluated based on information currently available, including advice of counsel and assessment of available insurance coverage. The Company establishes an accrual for specific legal matters when it determines that the likelihood of an unfavorable outcome is probable and the loss is reasonably estimable. Once established, each accrual is adjusted to reflect any subsequent developments. Legal contingencies are subject to inherent uncertainties, and unfavorable rulings may occur that could cause the Company to either adjust its litigation accrual or incur actual losses that exceed the current estimate, which ultimately could have a material adverse effect, either individually or in the aggregate, on its business, financial condition, or operating results. The Company will consider settlement of cases when it is in the best interests of the Company and its stakeholders. The Company intends to defend itself in all claims asserted against it, and management currently believes that the outcome of these contingencies will not be material, either individually or in the aggregate, to the Company or its consolidated financial position. Federal Deposit Insurance Corporation Special Assessment On November 29, 2023, the FDIC published a final rule implementing a special assessment for certain banks to recover losses incurred by protecting uninsured depositors of Silicon Valley Bank and Signature Bank upon their failure in March 2023. The final rule levies a special assessment to certain banks at a quarterly rate of 3.36 basis points based on their uninsured deposits balance reported as of December 31, 2022. The special assessment is to be collected for an anticipated total of eight quarterly assessment periods beginning with the first quarter of 2024, which has a payment date of June 28, 2024. Based on the final rule, the Company estimates that its special assessment charge is approximately $47.2 million. However, the FDIC retains the right to cease collection early, extend the special assessment collection period, and impose a final shortfall special assessment if actual losses exceed the amounts collected.

Parent Company Information

Parent Company Information	12 Months Ended
	Dec. 31, 2023
Condensed Financial Information Disclosure [Abstract]
Parent Company Information	Parent Company Financial Information The following tables summarize condensed financial information for the Parent Company only: CONDENSED BALANCE SHEETS December 31, (In thousands) 2023 2022 Assets: Cash and due from banks $ 406,754 $ 305,331 Intercompany debt securities 150,000 150,000 Investment in subsidiaries 9,131,026 8,631,202 Alternative investments 59,015 46,349 Other assets 13,314 13,358 Total assets $ 9,760,109 $ 9,146,240 Liabilities and stockholders’ equity: Senior notes $ 458,698 $ 480,878 Subordinated notes 512,802 514,930 Junior subordinated debt 77,320 77,320 Accrued interest payable 12,693 7,457 Due to subsidiaries 477 3,858 Other liabilities 8,123 5,611 Total liabilities 1,070,113 1,090,054 Stockholders’ equity 8,689,996 8,056,186 Total liabilities and stockholders’ equity $ 9,760,109 $ 9,146,240 CONDENSED STATEMENTS OF INCOME Years ended December 31, (In thousands) 2023 2022 2021 Income: Dividend income from bank subsidiary $ 600,000 $ 475,000 $ 200,000 Interest income on securities and interest-bearing deposits 11,259 5,955 3,444 Alternative investments income 1,272 6,416 13,033 Other non-interest income 908 112 75 Total income 613,439 487,483 216,552 Expense: Interest expense on borrowings 37,933 34,284 16,876 Merger-related expenses 2,111 40,314 16,266 Other non-interest expense 31,600 22,592 15,921 Total expense 71,644 97,190 49,063 Income before income taxes and equity in undistributed earnings of subsidiaries 541,795 390,293 167,489 Income tax benefit 15,106 20,799 3,121 Equity in undistributed earnings of subsidiaries 310,939 233,191 238,254 Net income $ 867,840 $ 644,283 $ 408,864 CONDENSED STATEMENTS OF COMPREHENSIVE INCOME Years ended December 31, (In thousands) 2023 2022 2021 Net income $ 867,840 $ 644,283 $ 408,864 Other comprehensive income (loss), net of tax: Derivative instruments 229 226 226 Other comprehensive income (loss) of subsidiaries 134,160 (662,606) (65,062) Other comprehensive income (loss), net of tax 134,389 (662,380) (64,836) Comprehensive income (loss) $ 1,002,229 $ (18,097) $ 344,028 CONDENSED STATEMENTS OF CASH FLOWS Years ended December 31, (In thousands) 2023 2022 2021 Operating activities: Net income $ 867,840 $ 644,283 $ 408,864 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed earnings of subsidiaries (310,939) (233,191) (238,254) Common stock contribution to charitable foundation — 10,500 — Other, net (8,312) (2,853) 3,562 Net cash provided by operating activities 548,589 418,739 174,172 Investing activities: Alternative investments (capital call), net of distributions (13,070) (16,292) (6,304) Net cash received in business combination — 193,238 — Net cash (used in) provided by investing activities (13,070) 176,946 (6,304) Financing activities: Repayment of long-term debt (16,752) — — Dividends paid to common stockholders (278,155) (247,767) (145,223) Dividends paid to preferred stockholders (16,650) (13,725) (7,875) Exercise of stock options 1,723 703 3,492 Common stock repurchase program (107,984) (322,103) — Common shares acquired related to stock compensation plan activity (16,278) (23,655) (4,384) Net cash (used in) financing activities (434,096) (606,547) (153,990) Net increase (decrease) in cash and cash equivalents 101,423 (10,862) 13,878 Cash and cash equivalents, beginning of period 305,331 316,193 302,315 Cash and cash equivalents, at end of period $ 406,754 $ 305,331 $ 316,193

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On January 24, 2024, the Bank acquired Ametros, a custodian and administrator of medical funds from insurance claims settlements that helps individuals manage their ongoing medical care through its CareGuard service and proprietary technology platform, for $350 million in cash, subject to customary adjustments. The Company believes that the acquisition will provide a fast-growing source of low-cost and long-duration deposits, new sources of non-interest income, and enhance its employee benefit and healthcare financial services expertise. The transaction will be accounted for as a business combination, and the assets acquired and liabilities assumed from Ametros will be recorded at fair value as of the acquisition date. Given the proximity between the transaction close date and the Company's Annual Report on Form 10-K, the preliminary purchase price allocation has not yet been completed. Management expects to complete the purchase price allocation later on in the first quarter of 2024. On February 12, 2024, the Bank closed on the sale of its mortgage servicing portfolio, as previously discussed in Note 5: Transfers and Servicing of Financial Assets. The Company received cash proceeds of $18.6 million and recognized a gain on sale of $11.9 million in non-interest income. On February 15, 2024, the Company repaid the $132.6 million principal balance due on its 4.375% senior fixed-rate notes. In the first quarter of 2024, through the date of issuance of this Annual Report on Form 10-K, the Company sold Municipal bonds and notes classified as available-for-sale for proceeds of $281.3 million, resulting in net realized losses of $11.3 million. The Company has evaluated subsequent events from the date of the Consolidated Financial Statements, and accompanying Notes thereto, through the date of issuance, and determined that, other than the above, there were no other significant events identified requiring recognition or disclosure.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net income	$ 867,840	$ 644,283	$ 408,864

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The Consolidated Financial Statements have been prepared in accordance with GAAP, and include the accounts of the Company and all other entities in which the Company has a controlling financial interest. Intercompany transactions and balances have been eliminated in consolidation. Assets under administration or assets under management that the Company holds or manages in a fiduciary or agency capacity for customers are not included on the accompanying Consolidated Balance Sheets. Certain prior period amounts have been reclassified to conform to the current year's presentation. These reclassifications did not have a significant impact on the Company's Consolidated Financial Statements.
Variable Interest Entities	Principles of Consolidation The purpose of Consolidated Financial Statements is to present the results of operations and the financial position of the Company and its subsidiaries as if the consolidated group were a single economic entity. In accordance with the applicable accounting guidance for consolidations, the Consolidated Financial Statements include any VOE in which the Company has a controlling financial interest and any VIE for which the Company is deemed to be the primary beneficiary. The Company generally consolidates its VOEs if the Company, directly or indirectly, owns more than 50% of the outstanding voting shares of the entity, and if the non-controlling stockholders do not hold any substantive participating or controlling rights. The Company evaluates VIEs to understand the purpose and design of the entity, and its involvement in the ongoing activities of the VIE, and will consolidate the VIE if it has (i) the power to direct the activities of the VIE that most significantly affect the VIE's economic performance, and (ii) an obligation to absorb losses of the VIE, or the right to receive benefits from the VIE, that could potentially be significant to the VIE. The Company accounts for unconsolidated partnerships and certain other investments using the equity method of accounting if it has the ability to significantly influence the operating and financial policies of the investee. This is generally presumed to exist when the Company owns between 20% and 50% of a corporation, or when it has greater than 3% to 5% interest in a limited partnership or similarly structured entity. Additional information regarding consolidated and non-consolidated VIEs can be found within Note 15: Variable Interest Entities. Use of Estimates The preparation of the Consolidated Financial Statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Business Combinations Business combinations are accounted for under the acquisition method, in which the identifiable assets acquired and liabilities assumed are generally measured and recognized at fair value as of the acquisition date, with the excess of the purchase price over the fair value of the net assets acquired recognized as goodwill. Items such as acquired ROU lease assets and operating lease liabilities as lessee, employee benefit plans, and income-tax related balances are recognized in accordance with other applicable GAAP, which may result in measurements that differ from fair value. After the adoption of ASU No. 2021-08—Business Combinations (Topic 805)—Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, contract assets and contract liabilities from contracts with customers discussed below, may result in measurements that differ from fair value as well. Business combinations are included in the Consolidated Financial Statements from the respective dates of acquisition. Historical reporting periods reflect only the results of legacy Webster operations. Merger-related costs are expensed in the period incurred and presented within the applicable non-interest expense category. Additional information regarding the Company's mergers and acquisitions can be found within Note 2: Mergers and Acquisitions.
Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents is comprised of cash and due from banks and interest-bearing deposits. Cash equivalents have an original maturity of three months or less. Cash and due from banks includes cash on hand, certain deposits at the FRB, and cash due from banks. Restricted cash related to Federal Reserve System requirements and cash collateral received on derivative positions are also included in Cash and due from banks. Interest-bearing deposits includes deposits at the FRB in excess of reserve requirements, if any, and federal funds sold to other financial institutions.
Investment Securities	Investments in Debt Securities Debt security transactions are recognized on the trade date, which is the date the order to buy or sell the security is executed. Investments in debt securities are classified as available-for-sale or held-to-maturity at the time of purchase. Any classification change subsequent to the trade date is reviewed for compliance with corporate objectives and accounting policies. Debt securities classified as available-for-sale are recorded at fair value with unrealized gains and losses recorded as a component of (AOCL). If a debt security is transferred from available-for-sale to held-to-maturity, it is recorded at fair value at the time of transfer and any respective gain or loss would be recorded as a separate component of (AOCL) and amortized as an adjustment to interest income over the remaining life of the security. Debt securities classified as available-for-sale are reviewed for credit losses when the fair value of a security falls below the amortized cost basis and the decline is evaluated to determine if any portion is attributable to credit loss. The decline in fair value attributable to credit loss is recorded directly to earnings, with a corresponding allowance for credit loss, limited to the amount that fair value is less than the amortized cost. If the credit quality subsequently improves, previously recorded allowance amounts may be reversed. An available-for-sale debt security will be placed on non-accrual status if collection of principal and interest in accordance with contractual terms is doubtful. When the Company intends to sell an impaired available-for-sale debt security, or if it is more likely than not that the Company will be required to sell the security prior to recovery of the amortized cost basis, the entire fair value adjustment will immediately be recognized in earnings through non-interest income. The gain or loss on sale is calculated using the carrying value plus any related (AOCL) balance associated with the securities sold. Debt securities classified as held-to-maturity are those in which the Company has the ability and intent to hold to maturity. Debt securities classified as held-to-maturity are recorded at amortized cost net of unamortized premiums and discounts. Discount accretion income and premium amortization expense are recognized as interest income using the effective interest method, with consideration given to prepayment assumptions on mortgage-backed securities. Premiums are amortized to the earliest call date for debt securities purchased at a premium, with explicit, non-contingent call features and are callable at a fixed price and preset date. Debt securities classified as held-to-maturity are reviewed for credit losses under the CECL model with an allowance recorded on the balance sheet for expected lifetime credit losses. The ACL is calculated on a pooled basis using statistical models which include forecasted scenarios of future economic conditions. Forecasts revert to long-run loss rates implicitly through the economic scenario, generally over three years. If the risk for a particular security no longer matches the collective assessment pool, it is removed and individually assessed for credit deterioration. The non-accrual policy for held-to-maturity debt securities is the same as for available-for-sale debt securities. A zero credit loss assumption is maintained for U.S. Treasuries and agency-backed securities in both the available-for-sale and held-to-maturity portfolios, as applicable. This assumption is subject to quarterly review to ensure it remains appropriate. Additional information regarding investments in debt securities can be found within Note 3: Investment Securities. Investments in Equity Securities The Company’s accounting treatment for non-consolidated equity investments differs for those with and without readily determinable fair values. Equity investments with readily determinable fair values are recorded at fair value with changes in fair value recorded in non-interest income. For equity investments without readily determinable fair values, the Company elected the measurement alternative, and therefore carries these investments at cost, less impairment, if any, plus or minus changes in observable prices. Certain equity investments that do not have a readily available fair value may qualify for NAV measurement based on specific requirements. The Company's alternative investments accounted for at NAV consist of investments in non-public entities that generally cannot be redeemed since the Company’s investments are distributed as the underlying equity is liquidated. On a quarterly basis, the Company reviews its equity investments without readily determinable fair values for impairment. If the equity investment is considered impaired, an impairment loss equal to the amount by which the carrying value exceeds its fair value is recorded through a charge to earnings. The impairment loss may be reversed in a subsequent period if there are observable transactions for the identical or similar investment of the same issuer at a higher amount than the carrying amount that was established when the impairment was recognized. Impairments, as well as upward or downward adjustments resulting from observable price changes in orderly transactions for identical or similar investments, are included in non-interest income. Equity investments in entities that finance affordable housing and other community development projects provide a return primarily through the realization of tax benefits. The Company applies the proportional amortization method to account for its investments in qualified affordable housing projects. Investment in Federal Home Loan Bank and Federal Reserve Bank Stock The Bank is a member of the FHLB and the Federal Reserve System, and is required to maintain an investment in capital stock of both the FHLB and FRB. Based on redemption provisions, FHLB and FRB stock has no quoted market value and is carried at cost. Membership stock is reviewed for impairment if economic circumstances would warrant review.
Loans Held for Sale	Loans Held for Sale Loans that are classified as held for sale at the time of origination are accounted for under the fair value option. Loans not originated for sale but subsequently transferred to held for sale are valued at the lower of cost or fair value on an individual asset basis. Any cost amount in excess of fair value is recorded as a valuation allowance and recognized as a reduction of other non-interest income. Gains or losses on the sale of loans held for sale are recorded either as part of Mortgage banking activities or Other income on the accompanying Consolidated Statements of Income. Cash flows from the sale of loans that were originated for sale are presented within Operating activities on the accompanying Consolidated Statements of Cash Flows, whereas cash flows from the sale of loans that were originated for investment and then subsequently transferred to held for sale are presented within Investing activities. Additional information regarding mortgage banking activities and loans sold can be found within Note 5: Transfers and Servicing of Financial Assets.
Transfers and Servicing of Financial Assets	Transfers and Servicing of Financial Assets Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is generally considered to have been surrendered when: (i) the transferred assets are legally isolated from the Company or its consolidated affiliates, even in bankruptcy or other receivership, (ii) the transferee has the right to pledge or exchange the assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Company, and (iii) the Company does not maintain the obligation or unilateral ability to reclaim or repurchase the assets. The Company sells financial assets in the normal course of business, the majority of which are residential mortgage loan sales to government-sponsored enterprises through established programs, as well as commercial loan sales through participation agreements, and other individual or portfolio loan and securities sales. In accordance with the accounting guidance for asset transfers, the Company considers any ongoing involvement with transferred assets in determining whether the assets can be derecognized from the balance sheet. With the exception of servicing, the Company’s continuing involvement with financial assets sold is minimal, and generally is limited to market customary representation and warranty clauses covering certain characteristics of the mortgage loans that were sold, and the Company's origination process. The gain or loss on sale depends on the previous carrying amount of the transferred financial assets, the consideration received, and any other assets obtained or liabilities incurred in exchange for the transferred assets. When the Company sells financial assets, it may retain servicing rights and/or other interests in the financial assets. Servicing assets and any other interests held by the Company are recorded at fair value upon transfer, and subsequently carried at the lower of cost or fair value. Additional information regarding transfers of financial assets and mortgage servicing assets can be found within Note 5: Transfers and Servicing of Financial Assets.
Loans and Leases	Loans and Leases Loans and leases are stated at the principal amount outstanding, net of amounts charged-off, unamortized premiums and discounts, and deferred loan and lease fees or costs, which are recognized as yield adjustments in interest income using the effective interest method. These yield adjustments are amortized over the contractual life of the related loans and leases and are adjusted for prepayments, as applicable. Interest on loans and leases is credited to interest income as earned based on the interest rate applied to principal amounts outstanding. Amounts of cash receipts and cash payments for loans and leases are presented net within Investing activities on the Consolidated Statements of Cash Flows. Non-accrual Loans Loans are placed on non-accrual status when full collection of principal and interest in accordance with contractual terms is not expected based on available information, which generally occurs when principal or interest payments become 90 days delinquent unless the loan is well secured and in the process of collection, or sooner if circumstances indicate that the borrower may be unable to meet contractual principal or interest payments. The Company considers a loan to be “well-secured” when it is secured by collateral in the form of liens on or pledges of real or personal property that have a realizable value sufficient to discharge the debt in full, or when it is secured by a contractual guarantee of a financially responsible party. The Company considers a loan “in the process of collection” if collection of the debt is proceeding in due course either through legal action or through collection efforts not involving legal action that are reasonably expected to result in repayment of the debt or in its restoration to a current status in the near future. When loans and leases are placed on non-accrual status, the accrual of interest income and the amortization or accretion of premiums, discounts, and deferred fees and costs is discontinued, and any previously accrued interest is reversed as a reduction of interest income. For commercial loans and leases, if the Company determines that repayment of non-accrual loans and leases is not expected, any payment received is applied to principal until the unpaid balance has been fully recovered. Any excess is then credited to interest income. For consumer loans, if the Company determines that principal can be repaid, interest payments are taken into income as received on a cash basis. Loans are generally removed from non-accrual status when they become current as to principal and interest or demonstrate a period of performance under the contractual terms and, in the opinion of management, are fully collectible as to principal and interest. For commercial loans, a sustained period of repayment performance is generally required. Pursuant to regulatory guidance, a loan discharged under Chapter 7 of the U.S. bankruptcy code is removed from non-accrual status when full repayment of the remaining pre-discharged contractual principal and interest is expected, and there have been at least six consecutive months of current payments. Additional information regarding non-accrual loans and leases can be found within Note 4: Loans and Leases.
Allowance for Loan and Lease Losses and Reserve for Unfunded Commitments	Allowance for Credit Losses on Loans and Leases The ACL on loans and leases, which is established through a provision charged to expense, is a contra-asset account that offsets the amortized cost basis of loans and leases for the credit losses that are expected to occur over the life of the asset. Executive management reviews and advises on the adequacy of the allowance, which is maintained at a level that management deems to be sufficient to cover expected credit losses within the loan and lease portfolios. The Company has elected to present accrued interest receivable separately from the amortized cost basis of Loans and leases on the accompanying Consolidated Balance Sheets. An ACL on accrued interest for a loan is not measured as accrued interest income is reversed against interest income for non-accrual loans immediately after their non-accrual classification. The ACL on loans and leases is determined using the CECL model, whereby an expected lifetime credit loss is recognized at the origination or purchase of an asset, including those acquired through a business combination, which is then reassessed at each reporting date over the contractual life of the asset. The calculation of expected credit losses includes consideration of past events, current conditions, and reasonable and supportable economic forecasts that affect the collectability of the reported amounts. Generally, expected credit losses are determined through a pooled, collective assessment of loans and leases with similar risk characteristics. However, if the risk characteristics of a loan or lease change such that it no longer matches that of the collectively assessed pool, it is removed from the population and individually assessed for credit losses. The total ACL on loans and leases recorded by management represents the aggregated estimated credit loss determined through both the collective and individual assessments. Collectively Assessed Loans and Leases. Collectively assessed loans and leases are segmented based on product type and credit quality, and expected losses are determined using a PD, LGD, EAD, or loss rate framework. For portfolios using the PD, LGD, and EAD framework, expected credit losses are calculated as the product of the probability of a loan defaulting, expected loss given the occurrence of a default, and the expected exposure of a loan at default. Summing the product across loans over their lives yields the lifetime expected credit losses for a given portfolio. The Company’s PD and LGD calculations are predictive models that measure the current risk profile of the loan pools using forecasts of future macroeconomic conditions, historical loss information, loan-level risk attributes, and credit quality indicators. The calculation of EAD follows an iterative process to determine the expected remaining principal balance of a loan based on historical paydown rates for loans of a similar segment within the same portfolio. The calculation of portfolio exposure in future quarters incorporates expected losses, the loan's amortization schedule, and prepayment rates. Under the loss rate framework, expected credit losses are estimated using a loss rate that is multiplied by the amortized cost of the asset at the balance sheet date. For each loan segment identified, management applies an expected historical loss trend based on third-party loss estimates, and correlates them to observed economic metrics, and reasonable and supportable forecasts of economic conditions. The Company’s models incorporate a single economic forecast scenario and macroeconomic assumptions over a reasonable and supportable forecast period. The development of the reasonable and supportable forecast period assumes that each macroeconomic variable will revert to long-term expectations, with reversion characteristics unique to specific economic indicators and forecasts. Reversion towards long-term expectations generally begins two to three years from the forecast start date and is complete within three to five years. Certain models use output reversion and revert to mean historical loss rates on a straight-line basis in the third year of the forecast. Other models incorporate a reasonable and supportable forecast of various macroeconomic variables over the remaining life of the Company's assets. Historical loss rates are based on approximately 10 years of recently available data and are updated annually. Macroeconomic variables are used as inputs to the loss models and are selected based on the correlation of the variables to credit losses for each class of financing receivable as follows: the commercial models use unemployment, gross domestic product, commercial real estate price indices, and retail sales (for commercial unfunded); the residential model uses the Case-Shiller Home Price Index; the home equity loan and line of credit models use interest rate spreads between U.S. Treasuries and corporate bonds and, in addition, the home equity loan model also uses the Federal Housing Finance Agency Home Price Index; and the personal loan and credit line models use the Case-Shiller Home Price Index and Federal Housing Finance Agency Home Price Index. Forecasted economic scenarios are sourced from a third party. Data from the baseline forecast scenario is used as the input to the modeled loss calculation. Changes in forecasts of macroeconomic variables will impact expectations of lifetime credit losses calculated by the loss models. However, the impact of changes in macroeconomic forecasts may be different for each portfolio and will reflect the credit quality and nature of the underlying assets at that time. A portion of the collective ACL is comprised of qualitative adjustments for risk characteristics that are not reflected or captured in the quantitative models, but are likely to impact the measurement of estimated credit losses. Qualitative factors are based on management's judgement of the Company, market, industry, or business specific data including loan trends, portfolio segment composition, and loan rating or credit scores. Qualitative adjustments may be applied in relation to economic forecasts when relevant facts and circumstances are expected to impact credit losses, particularly in times of significant volatility in economic activity. In addition to the above considerations, the ACL calculation includes expectations of prepayments and recoveries. Extensions, renewals, and modifications are not included in the collective assessment. Individually Assessed Loans and Leases. When loans and leases no longer match the ri sk characteristics of the collectively assessed pool, they are removed from the collectively assessed population and individually assessed for credit losses. Generally, all non-accrual loans and loans with a charge-off are individually assessed. Individual assessment for commercial loans that are considered to be collateral dependent is based on the fair value of the collateral less estimated cost to sell, the present value of the expected cash flows from the operation of the collateral, or a scenario weighted approach of both of these methods. If a loan is not collateral dependent, the individual assessment is based on a discounted cash flow approach. For collateral dependent commercial loans and leases, the Company's process requires the Company to determine the fair value of the collateral by obtaining a third-party appraisal or asset valuation, an interim valuation analysis, blue book reference, or other internal methods. Fair value of the collateral for commercial loans is reevaluated quarterly. Whenever the Company has a third-party real estate appraisal performed by independent licensed appraisers, a licensed in-house appraisal officer or qualified individual reviews these appraisals for compliance with the Financial Institutions Reform Recovery and Enforcement Act and the Uniform Standards of Professional Appraisal Practice. Individual assessments for residential and home equity loans are based on a discounted cash flow approach or the fair value of collateral less the estimated costs to sell. Other consumer loans are individually assessed using a loss factor approach based on historical loss rates. For residential and consumer collateral dependent loans, a third-party appraisal is obtained upon loan default. Fair value of the collateral for residential and consumer collateral dependent loans is reevaluated every six months, by either obtaining a new appraisal or other internal valuation method. Fair value is also reassessed, with any excess amount charged off, for residential and home equity loans that reach 180 days past due per Federal Financial Institutions Examination Council guidelines. A fair value shortfall relative to the amortized cost balance is reflected as a valuation allowance within the ACL on loans and leases. Subsequent to an appraisal or other fair value estimate, should reliable information come to management's attention that the value has declined further, an additional allowance may be recorded to reflect the particular situation, thereby increasing the ACL on loans and leases. If the credit quality subsequently improves, the allowance is reversed up to a maximum of the previously recorded credit losses. Any individually assessed loan for which no specific valuation allowance is necessary is the result of either sufficient cash flow or sufficient collateral coverage relative to the amortized cost. Additional information regarding the ACL on loans and leases can be found within Note 4: Loans and Leases. Charge-off of Uncollectible Loans If all or a portion of a loan is deemed to be no longer collectible upon the occurrence of a loss-confirming event, a charge-off may be recognized. Charge-offs reduce the amortized cost basis of the loan with a corresponding reduction to the ACL. For commercial loans, loss confirming events usually involve the receipt of specific adverse information about the borrower. The Company will generally recognize charge-offs for commercial loans on a case-by-case basis based on the review of the entire credit relationship and financial condition of the borrower. Loss-confirming events for consumer loans, such as bankruptcy or protracted delinquency, are typically based on established thresholds rather than by specific adverse information about the borrower. PCD Loans and Leases PCD loans and leases are defined as those that have experienced a more-than-insignificant deterioration in credit quality since origination. The Company considers a variety of factors to evaluate and identify whether acquired loans are PCD, including but not limited to, nonaccrual status, delinquency, whether the borrower is experiencing financial difficulty, partial charge-offs, decreases in FICO scores, risk rating downgrades, and other factors. Upon acquisition, expected credit losses are added to the fair value of individual PCD loans and leases to determine the amortized cost basis. After initial recognition, any changes to the estimate of expected credit losses, favorable or unfavorable, are recorded as a provision for credit loss during the period of change. PCD accounting is also applied to loans and leases previously charged-off by the acquiree if the Company has contractual rights to the cash flows at the acquisition date. The Company recognizes an additional ACL for amounts previously charged-off by the acquiree with a corresponding increase to the amortized costs basis of the acquired asset. Balances deemed to be uncollectible are immediately charged-off in accordance with the Company’s charge-off policies, resulting in the establishment of the initial ACL for PCD loans and leases to be recorded net of these uncollectible balances. Allowance for Credit Losses on Unfunded Loan Commitments The ACL on unfunded loan commitments provides for potential exposure inherent with funding the unused portion of legal commitments to lend that are not unconditionally cancellable by the Company. Accounting for unfunded loan commitments follows the CECL model. The calculation of the allowance includes the probability of funding to occur and a corresponding estimate of expected lifetime credit losses on amounts assumed to be funded. Loss calculation factors are consistent with the ACL methodology for funded loans using the PD and LGD applied to the underlying borrower risk and facility grades, a draw down factor applied to utilization rates, relevant forecast information, and management's qualitative factors. The ACL on unfunded credit commitments is included within Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets. Additional information regarding the ACL on unfunded loan commitments can be found within
Troubled Debt Restructurings	Troubled Debt Restructurings Prior to the adoption of ASU No. 2022-02—Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures, a modified loan was considered a TDR when the following two conditions were met: (i) the borrower was experiencing financial difficulty, and (ii) the modification constituted a concession (i.e., the modified terms of the loan were more attractive to the borrower than standard market terms). The Company's most common types of TDRs included covenant modifications and forbearance. The Company’s policy was to place consumer loan TDRs, except those that were performing prior to TDR classification, on non-accrual status for a minimum period of six months. Commercial loan TDRs were evaluated on a case-by-case basis when determining whether or not to place them on non-accrual status. Loans qualified for return-to-accrual status when the borrower had demonstrated performance with the restructured terms of the loan agreement for a minimum period of six months. TDRs were also to be reported as such for the remaining life of the loan and individually assessed for expected credit losses under the Company’s ACL methodology. Upon adoption of ASU No. 2022-02 on January 1, 2023, the existing measurement and disclosure requirements for TDRs by creditors were eliminated and disclosure requirements for certain loan refinancings and restructurings by creditors when a borrower is experiencing financial difficulty were enhanced. Additional information regarding modifications to borrowers experiencing financial difficulty can be found under the section captioned “Accounting Standards Adopted During the Current Year” and within Note 4: Loans and Leases.
Foreclosed and Repossessed Assets	Foreclosed and Repossessed Assets Real estate acquired through foreclosure or completion of a deed in lieu of foreclosure and other assets acquired through repossession are recorded at fair value less estimated cost to sell at the date of transfer. Subsequent to the acquisition date, the foreclosed and repossessed assets are carried at the lower of cost or fair value less estimated selling costs and are included within Other assets on the accompanying Consolidated Balance Sheets. Independent appraisals generally are obtained to substantiate fair value and may be subject to adjustment based upon historical experience or specific geographic trends impacting the property. Upon transfer to OREO, the excess of the loan balance over fair value less cost to sell is charged off against the ACL. Subsequent write-downs in value, maintenance costs as incurred, and gains or losses upon sale are charged to Other expense on the accompanying Consolidated Statements of Income.
Premises and Equipment	Property and Equipment Property and equipment is carried at cost, less accumulated depreciation and amortization. Depreciation and amortization is computed on a straight-line basis over the estimated useful lives of the assets, as illustrated in the following table. If shorter, leasehold improvements are amortized over the terms of the respective leases. Minimum Maximum Building and improvements 5 - 40 years Leasehold improvements 5 - 20 years Furniture, fixtures, and equipment 5 - 10 years Data processing equipment and software 3 - 7 years Repairs and maintenance costs are expensed as incurred, while significant improvements are capitalized. Property and equipment that is actively marketed for sale is reclassified to assets held for disposition. The cost and accumulated depreciation and amortization of property and equipment that is sold, retired, or otherwise disposed of, is eliminated from accounts and any resulting gain or loss is recorded as Other income or Other expense, respectively, on the accompanying Consolidated Statements of Income. Additional information regarding property and equipment can be found within Note 6: Premises and Equipment. Operating Leases As lessee, ROU lease assets and their corresponding lease liabilities are recognized on the lease commencement date. A ROU asset is measured based on the present value of the future minimum lease payments, adjusted for any initial direct costs, incentives, or other payments prior to the lease commencement date. A lease liability represents a legal obligation to make lease payments and is measured based on the present value of the future minimum lease payments, discounted using the rate implicit in the lease or the Company’s incremental borrowing rate. Variable lease payments that are dependent on either an index or rate are initially measured using the index or rate at the commencement date and included in the measurement of the lease liability. Renewal options are not included as part of the ROU asset or lease liability unless the renewal option is deemed reasonably certain to exercise. ROU lease assets and operating lease liabilities are included in Premises and equipment and Accrued expenses and other liabilities, respectively, on the accompanying Consolidated Balance Sheets. For real estate leases, lease components and non-lease components are accounted for as a single lease component if the
Goodwill	Goodwill Goodwill represents the excess purchase price of businesses acquired over the fair value of the identifiable net assets acquired and is assigned to specific reporting units. Goodwill is not subject to amortization but rather is evaluated for impairment annually, or more frequently if events occur or circumstances change indicating it would more likely than not result in a reduction of the fair value of the reporting units below their carrying value, including goodwill. Goodwill may be evaluated for impairment by first performing a qualitative assessment. If the qualitative assessment indicates that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, including goodwill, or, if for any other reason the Company determines to it be appropriate, then a quantitative assessment will be performed. The quantitative assessment process utilizes an income and market approach to arrive at an indicated fair value range for the reporting units. The fair value calculated for each reporting unit is compared to its carrying amount, including goodwill, to ascertain if goodwill impairment exists. If the fair value exceeds the carrying amount, including goodwill for a reporting unit, it is not considered to be impaired. If the fair value is below the carrying amount, including goodwill for a reporting unit, then an impairment charge is recognized for the amount by which the carrying amount exceeds the calculated fair value, up to but not exceeding the amount of goodwill allocated to the reporting unit. The resulting amount is charged to Other expense on the accompanying Consolidated Statements of Income. The Company completed a quantitative assessment for its reporting units during its most recent annual impairment review. Based on this qualitative assessment, the Company determined that there was no evidence of impairment to the balance of its goodwill. Additional information regarding goodwill can be found within Note 8: Goodwill and Other Intangible Assets.
Other Intangible Assets	Other Intangible Assets Other intangible assets represent purchased assets that lack physical substance but can be distinguished from goodwill because of contractual or other legal rights, or because it is capable of being sold or exchanged either separately or in combination with a related contract, asset, or liability. Other intangible assets with finite useful lives, such as core deposits and customer relationships, are amortized to non-interest expense over their estimated useful lives and are evaluated for impairment whenever events occur or circumstances change indicating that the carrying amount of the asset may not be recoverable. Additional information regarding other intangible assets can be found within Note 8: Goodwill and Other Intangible Assets.
Cash Surrender Value of Life Insurance	Cash Surrender Value of Life Insurance Bank-owned life insurance represents the cash surrender value of life insurance policies on certain current and former employees of Webster and Sterling. Cash surrender value increases and decreases are recorded in non-interest income. Death benefit proceeds in excess of the cash surrender value are recorded in other non-interest income upon the death of the insured.
Securities Sold Under Agreements to Repurchase	Securities Sold Under Agreements to Repurchase These agreements are accounted for as secured financing transactions since the Company maintains effective control over the transferred investment securities and the transfer meets the other criteria for such treatment. Obligations to repurchase the sold investment securities are reflected as a liability on the accompanying Consolidated Balance Sheets. The investment securities sold with agreement to repurchase to wholesale dealers are transferred to a custodial account for the benefit of the dealer or to the bank with whom each transaction is executed. The dealers or banks may sell, loan, or otherwise dispose of such securities to other parties in the normal course of their operations and agree to resell to the Company the same securities at the maturity date of the agreements. The Company also enters into repurchase agreements with Bank customers. The investment securities sold with agreement to repurchase to Bank customers are not transferred, but internally pledged to the repurchase agreement transaction. Additional information regarding securities sold under agreements to repurchase can be found within Note 11: Borrowings.
Revenue Recognition for Alternative Revenue Programs, Policy [Policy Text Block]	Revenue From Contracts With Customers Revenue from contracts with customers comprises non-interest income earned in exchange for services provided to customers and is recognized either when services are completed or as they are rendered. These revenue streams include Deposit service fees, Wealth and investment services, and non-significant portions of Loan and lease related fees and Other income on the accompanying Consolidated Statements of Income. The Company identifies the performance obligations included in its contracts with customers, determines the transaction price, allocates the transaction price to the performance obligations, as applicable, and recognizes revenue when the performance obligations are satisfied. Services provided over a period of time are generally transferred to customers evenly over the term of the contracts, and revenue is recognized evenly over the period the services are provided. Contract assets are included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets. Payment terms vary by services offered, and generally the time between the completion of performance obligations and receipt of payment is not significant. Additional information regarding contracts with customers can be found within Note 22: Revenue from Contracts with Customers.
Share-based Compensation	Share-Based Compensation The Company maintains a stock compensation plan that provides for the grant of stock options, stock appreciation rights, restricted stock, performance-based stock, and stock units to employees and directors. Share awards are issued from available treasury shares. Stock compensation expense is recognized over the required service vesting period for each award based on the grant date fair value, and is included within Compensation and benefits expense on the accompanying Consolidated Statements of Income. For time-based restricted stock awards and average return on equity performance-based restricted stock awards, fair value is measured using the closing price of Webster common stock at the grant date. For total stockholder return performance-based restricted stock awards, fair value is measured using the Monte Carlo simulation model. Performance-based restricted stock awards ultimately vest in a range from 0% to 150% of the target number of shares under the grant. Compensation expense may be subject to adjustment based on management's assessment of the Company's average return on equity performance relative to the target number of shares condition. Stock option awards use the Black-Scholes Option-Pricing Model to measure fair value at the grant date. Excess tax benefits or tax deficiencies result when tax return deductions differ from recognized compensation cost determined using the grant-date fair value approach for financial statement purposes. Dividends are paid on time-based shares upon grant and are non-forfeitable, while dividends are accrued on performance-based awards and are paid with the vested shares when the performance target is met. Additional information regarding share-based compensation can be found within Note 20: Share-Based Plans.
Income Taxes	Income Taxes Income tax expense (benefit) is comprised of two components, current and deferred. The current component represents income taxes payable or refundable for the current period based on applicable tax laws, while the deferred component represents the tax effects of temporary differences between amounts recognized for financial accounting and tax purposes. DTAs and DTLs reflect the tax effects of such differences that are anticipated to result in taxable or deductible amounts in the future when the temporary differences reverse. DTAs are recognized if it is more likely than not that they will be realized, and may be reduced by a valuation allowance if it is more likely than not that all or some portion will not be realized. Uncertain tax positions that meet a more likely than not recognition threshold are initially and subsequently measured as the largest amount of tax benefit that has a greater than 50% likelihood of being realized upon settlement with a taxing authority based on knowledge of all relevant information. The determination of whether or not a tax position meets the more likely than not recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to management judgment. The Company recognizes interest and penalties on uncertain tax positions and interest on refundable income taxes as a component of Income tax expense and Other income, respectively, on the accompanying Consolidated Statements of Income. Additional information regarding income taxes can be found within Note 9: Income Taxes.
Earnings Per Common Share	Earnings per Common Share Earnings per common share is calculated under the two-class method. Basic earnings per common share is computed by dividing earnings applicable to common stockholders by the weighted-average number of common shares outstanding, excluding outstanding participating securities, during the pertinent period. Certain unvested restricted stock awards are considered participating securities as they have non-forfeitable rights to dividends. Diluted earnings per common share is computed using the weighted-average number of shares determined for the basic earnings per common share computation plus the dilutive effect of shares resulting from stock compensation and warrants for common stock using the treasury stock method. A reconciliation between the weighted-average common shares used in calculating basic earnings per common share and the weighted-average common shares used in calculating diluted earnings per common share can be found within Note 16: Earnings Per Common Share.
Comprehensive Income	Comprehensive Income (Loss) Comprehensive income (loss) includes all changes in equity during the period, except those resulting from transactions with stockholders. Comprehensive income (loss) comprises net income and the after-tax effect changes in the following items: net unrealized gain (loss) on available-for-sale securities, net unrealized gain (loss) on derivative instruments, and net actuarial gain (loss) related to defined benefit pension and other postretirement benefit plans. Comprehensive income (loss) is reported on the accompanying Consolidated Statements of Stockholders' Equity and the accompanying Consolidated Statements of Co mprehensive Income. Additional information regarding comprehensive income (loss) can be found within Note 13: Accumulated Other Comprehensive (Loss) Income, Net of Tax.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities Derivatives are recognized at fair value and are included in Accrued interest receivable and other assets and Accrued expenses and other liabilities, as applicable, on the accompanying Consolidated Balance Sheets. The value of exchange-traded contracts is based on quoted market prices, whereas non-exchange traded contracts are valued based on dealer quotes, pricing models, discounted cash flow methodologies, or similar techniques in which the determination of fair value may require management judgment or estimation. Net cash flows from derivative contract assets and liabilities are presented within Operating activities on the accompanying Consolidated Statements of Cash Flows. Derivatives Designated in Hedge Relationships. The Company uses derivatives to hedge exposures or to modify interest rate characteristics for certain balance sheet accounts under its interest rate risk management strategy. The Company designates derivatives in qualifying hedge relationships either as fair value or cash flow hedges for accounting purposes. Derivative financial instruments receive hedge accounting treatment if they are qualified and are properly designated as a hedge, and remain highly effective in offsetting changes in the fair value or cash flows attributable to the risk being hedged, both at hedge inception and on an ongoing basis throughout the life of the hedge. Quarterly prospective and retrospective assessments are performed to ensure hedging relationships continue to be highly effective. If a hedge relationship is no longer highly effective, hedge accounting would be discontinued. The change in fair value on a derivative that is designated and qualifies as a fair value hedge, as well as the offsetting change in fair value on the hedged item attributable to the risk being hedged, is recognized in earnings. The gain or loss on a derivative that is designated and qualifies as a cash flow hedge is initially recorded as a component of (AOCL), and either subsequently reclassified to interest income as hedged interest payments are received or to interest expense as hedged interest payments are made during the same period in which the hedged transaction affects earnings. Derivatives Not Designated in Hedge Relationships . The Company also enters into derivative transactions that are not designated in hedge relationships. Derivative financial instruments not designated in hedge relationships are recorded at fair value with changes in fair value recognized in Other income on the accompanying Consolidated Statements of Income. Offsetting Assets and Liabilities . Derivative assets and derivative liabilities with the same counterparty are presented on a net basis in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets when master netting agreements are in place. Cash collateral paid or received for non-exchange cleared transactions are presented net with the associated derivative assets and derivative liabilities. Securities collateral is not offset. Amounts paid to dealers for initial margin are also included in Accrued interest receivable and other assets. Additional information regarding derivatives can be found within Note 17: Derivative Financial Instruments.
Fair Value Measurements	Fair Value Measurements The Company measures many of its assets and liabilities on a fair value basis in accordance with ASC Topic 820, Fair Value Measurement. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value is used to measure certain assets and liabilities on a recurring basis when fair value is the primary basis of accounting, and on a non-recurring basis when evaluating assets or liabilities for impairment. Additional information regarding the Company's policies and methodologies used to measure fair value can be found within Note 18: Fair Value Measurements.
Employee Retirement Benefit Plan	Employee Retirement Benefit Plans The Company sponsors defined contribution postretirement benefit plans that are established under Section 401(k) of the Internal Revenue Code. Expenses to maintain the plans, as well as employer contributions, are charged to Compensation and benefits expense on the accompanying Consolidated Statements of Income. The Bank had offered a qualified noncontributory defined benefit pension plan and a non-qualified SERP to eligible employees and key executives who met certain age and service requirements, both of which were frozen effective December 31, 2007. The Bank also provides for OPEB to certain retired employees. In connection with the merger with Sterling, the Company also assumed the benefit obligations of Sterling's non-qualified SERP and OPEB plans. Pension contributions are funded in accordance with the requirements of the Employee Retirement Income Security Act. Net periodic benefit cost (income), which is based upon actuarial computations of current and future benefits for eligible employees, are charged to Other expense on the accompanying Consolidated Statements of Income. The funded status of the plans is recorded as an asset when over-funded or a liability when under-funded. Additional information regarding the defined benefit pension and postretirement benefit plans can be found within Note 19: Retirement Benefit Plans.
Recently Adopted and Issued Accounting Standards Updates	Accounting Standards Adopted During the Current Year ASU No. 2022-02—Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures In March 2022, the FASB issued ASU No. 2022-02, which eliminates the accounting guidance for TDRs by creditors in Subtopic 310-40, Receivables—Troubled Debt Restructurings by Creditors, while enhancing disclosure requirements for certain loan refinancings and restructurings by creditors when a borrower is experiencing financial difficulty. Specifically, rather than applying the recognition and measurement guidance for TDRs, an entity must apply the loan refinancing and restructuring guidance in paragraphs 310-20-35-9 through 35-11 to determine whether a modification results in a new loan or a continuation of an existing loan. In addition, the Update requires that an entity disclose current-period gross write-offs by year of origination for financing receivables and net investments in leases within the scope of Subtopic 326-20, Financial Instruments—Credit Losses—Measured at Amortized Cost in the vintage disclosures required by paragraph 326-20-50-6. Modifications to borrowers experiencing financial difficulty include principal forgiveness, interest rate reductions, payment delays, term extensions, or combinations thereof. Expected losses or recoveries on loans where modifications have been granted to borrowers experiencing financial difficulty have been factored into the ACL on loans and leases. Upon adoption of ASU 2022-02, the Company is no longer required to use a discounted cash flow (or reconcilable) method to measure the ACL resulting from a modification with a borrower experiencing financial difficulty. Accordingly, the Company now applies the same credit loss methodology it uses for similar loans that were not modified. The Company adopted the Update on January 1, 2023. The Company elected the option to apply the modified retrospective transition method related to the recognition and measurement of TDRs, which resulted in a $5.9 million increase to the Allowance for credit losses on loans and leases and a $1.6 million increase to DTAs, net, with a corresponding $4.3 million cumulative-effect adjustment to retained earnings as of the adoption date. The enhanced disclosure requirements provided for by the Update were adopted on a prospective basis. Reporting periods prior to the adoption of the Update are accounted for and presented in accordance with the applicable GAAP. Additional information regarding modifications granted to borrowers experiencing financial difficulty can be found within ASU No. 2022-01—Derivatives and Hedging (Topic 815): Fair Value Hedging—Portfolio Layer Method In March 2022, the FASB issued ASU No. 2022-01—Derivatives and Hedging (Topic 815): Fair Value Hedging—Portfolio Layer Method, which expands the current last-of-layer method of hedge accounting that permits only one hedged layer to allow multiple hedged layers of a single closed portfolio. To reflect that expansion, the last-of-layer method is renamed the portfolio layer method. Additionally, the amendments in this Update: (i) expand the scope of the portfolio layer method to include non-prepayable assets; (ii) specify eligible hedging instruments in a single-layer hedge; (iii) provide additional guidance on the accounting for and disclosure of hedge basis adjustments; and (iv) specify how hedge basis adjustments should be considered when determining credit losses for the assets included in the closed portfolio. An entity may also reclassify debt securities classified in the held-to-maturity category at the date of adoption to the available-for-sale category only if the entity applies portfolio layer method hedging to one or more closed portfolios that include those debt securities within a 30-day period. The Company adopted the Update on January 1, 2023 on a prospective basis. The adoption of this guidance did not have a material impact on the Company's Consolidated Financial Statements. The Company did not reclassify any debt securities from the held-to-maturity category to the available-for-sale category as permitted upon adoption. ASU No. 2021-08—Business Combinations (Topic 805)—Accounting for Contract Assets and Contract Liabilities from Contracts with Customers In October 2021, the FASB issued ASU No. 2021-08—Business Combinations (Topic 805)—Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, which requires that an acquirer recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with Topic 606, Revenue from Contracts with Customers. At the acquisition date, an acquirer should account for the related revenue contracts in accordance with Topic 606 as if it had originated the contracts. The Company adopted the Update on January 1, 2023 on a prospective basis. The adoption of this guidance did not have a material impact on the Company's Consolidated Financial Statements. Relevant Accounting Standards Issued But Not Yet Adopted ASU No. 2023-09—Income Taxes (Topic 740)—Improvements to Income Tax Disclosures In December 2023, the FASB issued ASU No. 2023-09—Income Taxes (Topic 740)—Improvements to Income Tax Disclosures, to provide more transparency about income tax information through improvements to income tax disclosures, primarily related to the rate reconciliation and income taxes paid information. Specifically, the amendments in this Update require disclosure of: (i) a tabular reconciliation, using both percentages and reporting currency amounts, with prescribed categories that are required to be disclosed, and the separate disclosure and disaggregation of prescribed reconciling items with an effect equal to 5% or more of the amount determined by multiplying pretax income from continuing operations by the application statutory rate; (ii) a qualitative description of the states and local jurisdictions that make up the majority (greater than 50%) of the effect of the state and local income taxes; and (iii) amount of income taxes paid, net of refunds received, disaggregated by federal, state, and foreign taxes and by individual jurisdictions that comprise 5% or more of total income taxes paid, net of refunds received. The amendments in this Update also include certain other amendments to improve the effectiveness of income tax disclosures. The Update is effective for annual periods beginning after December 15, 2024, with early adoption permitted. The amendments should be applied on a prospective basis; however, retrospective application is permitted. The Company is currently evaluating this guidance to determine the impact on its income tax disclosures. ASU No. 2023-07—Segment Reporting (Topic 280)—Improvements to Reportable Segment Disclosures In November 2023, the FASB issued ASU No. 2023-07—Segment Reporting (Topic 280)—Improvements to Reportable Segment Disclosures, to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. Specifically, the amendments in this Update require disclosure of: (i) significant segment expenses that are regularly provided to the chief operating decision maker and included within each reported measure of segment profit or loss; (ii) an amount for other segment items by reportable segment and a description of its composition; and (iii) the title and position of the chief operating decision maker and an explanation of how the chief operating decision maker uses each reported measure of segment profit or loss in assessing segment performance and deciding how to allocate resources. In addition, all annual disclosures about a reportable segment’s profit or loss and assets currently required by Topic 280, will be required in interim periods. Overall, the Update does not change how a public entity identifies its operating segments, aggregates those operating segments, or determines its reportable segments, or applies the quantitative thresholds to determine its reportable segments. The Update is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements, in which, upon transition, the segment expense categories and amounts disclosed in the prior periods should be based on the significant segment expense categories identified and disclosed in the period of adoption. The Company is currently evaluating this guidance to determine the impact on its segment reporting disclosures. ASU No. 2023-02—Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method (a consensus of the Emerging Issue Task Force) In March 2023, the FASB issued ASU No. 2023-02—Investments—Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method (a consensus of the Emerging Issues Task Force), which permits reporting entities to elect to account for their tax equity investments, regardless of the program from which the income tax credits are received, using the proportional amortization method if certain conditions are met. A reporting entity may make an accounting policy election to apply the proportional amortization method in accordance with paragraph 323-740-25-4 on a tax-credit-program by tax-credit-program basis rather than electing to apply the proportional amortization method at the reporting entity level or to individual investments. A reporting entity that applies the proportional amortization method to qualifying tax equity investments must account for the receipt of the investment tax credits using the flow-through method under Topic 740, Income Taxes, even if the entity applies the deferral method for other investment tax credit received. The amendments also remove certain guidance for Qualified Affordable Housing Project Investments, require the application of the delayed equity contribution guidance to all tax equity investments, and require specific disclosures that must be applied to all investments that generate income tax credits and other income tax benefits from a tax credit program for which the entity has elected to apply the proportional amortization method in accordance with Subtopic 323-740. The Update is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. The amendments generally must be applied on either a modified retrospective or retrospective basis with a cumulative-effect adjustment to retained earnings reflecting the difference between the previous method used to account for the tax equity investment and the application of the proportional amortization method since the investment was entered into. The Company will adopt the Update on January 1, 2024. The adoption of this guidance will not have a material impact on the Company's Consolidated Financial Statements and disclosures as its investments in tax credit structures are currently limited to LIHTC investments, which are already being accounted for using the proportional amortization method. ASU No. 2023-01—Leases (Topic 842): Common Control Arrangements In March 2023, the FASB issued ASU No. 2023-01—Leases (Topic 842): Common Control Arrangements, which requires that leasehold improvements associated with leases between entities under common control be: (i) amortized by the lessee over the useful lives of the leasehold improvements to the common control group (regardless of the lease term) as long as the lessee controls the use of the underlying asset (the leased asset) through a lease; however, if the lessor obtained the right to control the use of the underlying asset through a lease with another entity not within the same common control group, the amortization period may not exceed the amortization period of the common control group; and (ii) accounted for as a transfer between entities under common control through an adjustment to equity, if, and when, the lessee no longer controls the use of the underlying asset. Additionally, those leasehold improvements are subject to the impairment guidance in Topic 360, Property, Plant, and Equipment. The Update is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. The amendments either may be applied prospectively to all new and existing leasehold improvements recognized on or after the adoption date with any remaining unamortized balance of existing leasehold improvements amortized over their remaining useful life to the common control group determined at that date; or retrospectively to the beginning of the period in which the entity first applied Topic 842, with any leasehold improvements that otherwise would not have been amortized or impaired recognized through a cumulative-effect adjustment to the opening balance of retained earnings at the beginning of the earliest period presented in accordance with Topic 842. The Company will adopt the Update on January 1, 2024. The adoption of this guidance will not have a material impact on the Company's Consolidated Financial Statements and disclosures as its operating lease arrangements in which it is lessee are currently not between entities under common control. ASU No. 2022-03—Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restriction In June 2022, the FASB issued ASU No. 2022-03—Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions, which clarifies that a contractual restriction on the sale of an equity security is not considered part of the unit of account of the equity security, and therefore, is not considered in measuring fair value. The amendments also clarify that an entity cannot, as a separate unit of account, recognize and measure a contractual sale restriction, and requires the following disclosures for equity securities subject to contractual sale restrictions: (i) the fair value of equity securities subject to contractual sale restrictions reflected on the balance sheet; (ii) the nature and remaining duration of the restriction(s); and (iii) the circumstances that could cause a lapse in the restriction(s). The Update is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. For all entities except investment companies, the amendments should be applied prospectively with any adjustments from the adoption of the amendments recognized in earnings and disclosed on the date of adoption. The Company will adopt the Update on January 1, 2024. The adoption of this guidance will not have a material impact on the Company's Consolidated Financial Statements and disclosures. The Company does not currently consider contractual restrictions on the sale of an equity security in measuring fair value.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Property, Plant and Equipment	Property and equipment is carried at cost, less accumulated depreciation and amortization. Depreciation and amortization is computed on a straight-line basis over the estimated useful lives of the assets, as illustrated in the following table. If shorter, leasehold improvements are amortized over the terms of the respective leases. Minimum Maximum Building and improvements 5 - 40 years Leasehold improvements 5 - 20 years Furniture, fixtures, and equipment 5 - 10 years Data processing equipment and software 3 - 7 years The following table summarizes the components of premises and equipment: At December 31, (In thousands) 2023 2022 Land $ 73,916 $ 73,916 Buildings and improvements 107,794 106,180 Leasehold improvements 88,065 84,477 Furniture, fixtures, and equipment 68,680 71,542 Data processing equipment and software 94,030 128,153 Property and equipment 432,485 464,268 Less: Accumulated depreciation and amortization (186,365) (225,152) Property and equipment, net 246,120 239,116 ROU lease assets, net 183,441 191,068 Premises and equipment, net $ 429,561 $ 430,184

Investments, All Other Investme

Investments, All Other Investments (Tables)	12 Months Ended
	Dec. 31, 2023
Investments, All Other Investments [Abstract]
Activity in Affordable Housing Program Obligation	The following table summarizes the Company's LIHTC investments and related unfunded commitments: At December 31, (In thousands) 2023 2022 Gross investment in LIHTC investments $ 1,135,192 $ 797,453 Accumulated amortization (141,199) (69,424) Net investment in LIHTC investments $ 993,993 $ 728,029 Unfunded commitments for LIHTC investments $ 549,258 $ 335,959

Mergers and Acquisitions (Table

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2023
Business Combination and Asset Acquisition [Abstract]
Summary of Purchase Price Consideration	The following table summarizes the determination of the purchase price consideration: (In thousands, except share and per share data) Webster common stock issued 87,965,239 Price per share of Webster common stock on January 31, 2022 $ 56.81 Consideration for outstanding common stock 4,997,305 Consideration for preferred stock exchanged 138,942 Consideration for replacement equity awards (1) 43,877 Cash in lieu of fractional shares 176 Total purchase price consideration $ 5,180,300 (1) The fair value of the replacement equity awards issued by the Company and included in the consideration transferred pertains to services performed prior to the merger effective date. The fair value attributed to services performed after the merger effective date is being recognized over the required service vesting period for each award and recorded as Compensation and benefits expense on the accompanying Consolidated Statements of Income. During the years ended December 31, 2023, and 2022, the Company recognized an increase of $22.8 million and $18.8 million in stock compensation expense related to the replacement equity awards.
Summary of Purchase Price Allocation	The following table summarizes the final allocation of the purchase price to the fair value of the identifiable assets acquired and liabilities assumed from Sterling: (In thousands) Unpaid Principal Balance Fair Value Purchase price consideration $ 5,180,300 Assets: Cash and due from banks 510,929 Interest-bearing deposits 3,207 Investment securities available-for-sale 4,429,948 Federal Home Loan Bank and Federal Reserve Bank Stock 150,502 Loans held for sale 23,517 Loans and leases: Commercial non-mortgage $ 5,570,782 5,527,657 Asset-based 694,137 683,958 Commercial real estate 6,790,600 6,656,405 Multi-family 4,303,381 4,255,906 Equipment financing 1,350,579 1,314,311 Warehouse lending 647,767 643,754 Residential 1,313,785 1,281,637 Home equity 132,758 122,553 Other consumer 12,559 12,525 Total loans and leases $ 20,816,348 20,498,706 Deferred tax assets, net (59,716) Premises and equipment (1) 264,421 Other intangible assets 210,100 Bank-owned life insurance policies 645,510 Accrued interest receivable and other assets 986,729 Total assets acquired $ 27,663,853 Liabilities: Non-interest-bearing deposits $ 6,620,248 Interest-bearing deposits 16,643,755 Securities sold under agreements to repurchase and other borrowings 27,184 Long-term debt 516,881 Accrued expenses and other liabilities (1) 589,689 Total liabilities assumed $ 24,397,757 Net assets acquired 3,266,096 Goodwill $ 1,914,204 (1) Includes $100.0 million of ROU lease assets operating lease liabilities
Schedule of PCD Loans and Leases by Portfolio Segment	The following table reconciles the unpaid principal balance to the fair value of PCD loans and leases by portfolio segment: (In thousands) Commercial Consumer Total Unpaid principal balance $ 3,394,963 $ 541,471 $ 3,936,434 ACL at acquisition (115,464) (20,852) (136,316) Non-credit (discount) (40,947) (2,784) (43,731) Fair value $ 3,238,552 $ 517,835 $ 3,756,387
Summary of Supplemental Pro Forma Information	The following table summarizes supplemental pro forma financial information giving effect to the merger as if it had been completed on January 1, 2021: Years ended December 31, (In thousands) 2022 2021 Net interest income $ 1,961,005 $ 1,802,862 Non-interest income 440,783 487,301 Net income 869,639 574,927

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Summary of Investment Securities	Available-for-Sale The following table summarizes the amortized cost and fair value of available-for-sale securities by major type: At December 31, 2023 (In thousands) Amortized Cost (1) Unrealized Unrealized Losses Fair Value Government agency debentures $ 302,212 $ — $ (37,579) $ 264,633 Municipal bonds and notes 1,626,126 8 (52,901) 1,573,233 Agency CMO 52,994 — (4,053) 48,941 Agency MBS 3,568,140 32,461 (253,503) 3,347,098 Agency CMBS 2,569,438 18,204 (299,571) 2,288,071 CMBS 788,478 — (24,729) 763,749 Corporate debt 704,569 — (82,414) 622,155 Private label MBS 46,635 — (3,827) 42,808 Other 9,830 — (789) 9,041 Total available-for-sale $ 9,668,422 $ 50,673 $ (759,366) $ 8,959,729 At December 31, 2022 (In thousands) Amortized Cost (1) Unrealized Unrealized Losses Fair Value U.S. Treasury notes $ 755,968 $ — $ (38,928) $ 717,040 Government agency debentures 302,018 — (43,644) 258,374 Municipal bonds and notes 1,719,110 5 (85,913) 1,633,202 Agency CMO 64,984 — (5,019) 59,965 Agency MBS 2,461,337 26 (303,339) 2,158,024 Agency CMBS 1,664,600 — (258,114) 1,406,486 CMBS 929,588 — (32,948) 896,640 CLO 2,108 — (1) 2,107 Corporate debt 795,999 — (91,587) 704,412 Private label MBS 48,895 — (4,646) 44,249 Other 12,548 — (350) 12,198 Total available-for-sale $ 8,757,155 $ 31 $ (864,489) $ 7,892,697 (1) Accrued interest receivable on available-for-sale securities of $42.5 million and $36.9 million at December 31, 2023, and 2022, respectively, is excluded from amortized cost and is included in Accrued interest receivable and other assets on the accompanying Consolidated Balance Sheets.
Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value	Unrealized Losses The following tables summarize the gross unrealized losses and fair value of available-for-sale securities by length of time each major security type has been in a continuous unrealized loss position: At December 31, 2023 Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Unrealized Fair Unrealized Number of Fair Unrealized Government agency debentures $ — $ — $ 264,633 $ (37,579) 19 $ 264,633 $ (37,579) Municipal bonds and notes 18,066 (124) 1,536,656 (52,777) 386 1,554,722 (52,901) Agency CMO — — 48,941 (4,053) 36 48,941 (4,053) Agency MBS 71,187 (272) 1,945,221 (253,231) 457 2,016,408 (253,503) Agency CMBS 430,070 (16,137) 1,314,681 (283,434) 145 1,744,751 (299,571) CMBS 43,844 (856) 719,905 (23,873) 42 763,749 (24,729) Corporate debt 4,278 (27) 617,877 (82,387) 91 622,155 (82,414) Private label MBS — — 42,808 (3,827) 3 42,808 (3,827) Other — — 9,041 (789) 2 9,041 (789) Total $ 567,445 $ (17,416) $ 6,499,763 $ (741,950) 1,181 $ 7,067,208 $ (759,366) At December 31, 2022 Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Unrealized Fair Unrealized Number of Fair Unrealized U.S. Treasury notes $ 337,563 $ (19,167) $ 379,477 $ (19,761) 23 $ 717,040 $ (38,928) Government agency debentures 258,374 (43,644) — — 19 258,374 (43,644) Municipal bonds and notes 1,616,771 (85,913) — — 444 1,616,771 (85,913) Agency CMO 55,693 (4,640) 4,272 (379) 39 59,965 (5,019) Agency MBS 1,641,544 (206,412) 515,206 (96,927) 460 2,156,750 (303,339) Agency CMBS 485,333 (68,674) 921,153 (189,440) 132 1,406,486 (258,114) CMBS 273,150 (8,982) 598,490 (23,966) 52 871,640 (32,948) CLO — — 2,107 (1) 1 2,107 (1) Corporate debt 692,990 (89,692) 8,421 (1,895) 105 701,411 (91,587) Private label MBS 44,249 (4,646) — — 3 44,249 (4,646) Other 12,198 (350) — — 4 12,198 (350) Total $ 5,417,865 $ (532,120) $ 2,429,126 $ (332,369) 1,282 $ 7,846,991 $ (864,489)
Debt Securities, Held-to-maturity	The following table summarizes the amortized cost, fair value, and ACL on held-to-maturity securities by major type: At December 31, 2023 (In thousands) Amortized Cost (1) Unrealized Gains Unrealized Losses Fair Value Allowance Net Carrying Value Agency CMO $ 23,470 $ — $ (1,728) $ 21,742 $ — $ 23,470 Agency MBS 2,409,521 1,141 (284,776) 2,125,886 — 2,409,521 Agency CMBS 3,625,627 18,586 (514,534) 3,129,679 — 3,625,627 Municipal bonds and notes 916,104 2,440 (24,877) 893,667 209 915,895 CMBS 100,075 — (6,426) 93,649 — 100,075 Total held-to-maturity $ 7,074,797 $ 22,167 $ (832,341) $ 6,264,623 $ 209 $ 7,074,588 At December 31, 2022 (In thousands) Amortized Cost (1) Unrealized Gains Unrealized Losses Fair Value Allowance Net Carrying Value Agency CMO $ 28,358 $ — $ (2,060) $ 26,298 $ — $ 28,358 Agency MBS 2,626,114 827 (339,592) 2,287,349 — 2,626,114 Agency CMBS 2,831,949 845 (407,648) 2,425,146 — 2,831,949 Municipal bonds and notes 928,845 1,098 (47,183) 882,760 182 928,663 CMBS 149,613 — (9,713) 139,900 — 149,613 Total held-to-maturity $ 6,564,879 $ 2,770 $ (806,196) $ 5,761,453 $ 182 $ 6,564,697 The following table summarizes the carrying value of held-to-maturity securities pledged for deposits, borrowings, and other purposes: At December 31, (In thousands) 2023 2022 Pledged for deposits $ 1,212,824 $ 1,596,777 Pledged for borrowings and other 5,582,379 260,735 Total held-to-maturity securities pledged $ 6,795,203 $ 1,857,512
Debt Securities, Held-to-maturity, Allowance for Credit Loss	The following table summarizes the activity in the ACL on held-to-maturity securities: Years ended December 31, (In thousands) 2023 2022 2021 Balance, beginning of period $ 182 $ 214 $ 299 Provision (benefit) for credit losses 27 (32) (85) Balance, end of period $ 209 $ 182 $ 214
Summary of Debt Securities by Contractual Maturity	The following table summarizes the amortized cost and fair value of available-for-sale securities by contractual maturity: At December 31, 2023 (In thousands) Amortized Cost Fair Value Maturing within 1 year $ 37,908 $ 36,958 After 1 year through 5 years 644,959 616,176 After 5 years through 10 years 1,363,257 1,263,900 After 10 years 7,622,298 7,042,695 Total available-for-sale $ 9,668,422 $ 8,959,729 The following table summarizes the amortized cost and fair value of held-to-maturity securities by contractual maturity: At December 31, 2023 (In thousands) Amortized Cost Fair Value Maturing within 1 year $ 8,122 $ 8,136 After 1 year through 5 years 59,932 60,434 After 5 years through 10 years 363,498 349,083 After 10 years 6,643,245 5,846,970 Total held-to-maturity $ 7,074,797 $ 6,264,623
Debt Securities, Available-for-Sale	The following table summarizes the carrying value of available-for-sale securities pledged for deposits, borrowings, and other purposes: At December 31, (In thousands) 2023 2022 Pledged for deposits $ 2,102,115 $ 2,573,072 Pledged for borrowings and other 6,111,430 1,195,101 Total available-for-sale securities pledged $ 8,213,545 $ 3,768,173
Debt Securities, Held-to-maturity, Credit Quality Indicator	The following tables summarize the amortized cost of held-to-maturity securities based on their lowest publicly available credit rating: At December 31, 2023 Investment Grade (In thousands) Aaa Aa1 Aa2 Aa3 A1 A2 A3 Not Rated Agency CMOs $ — $ 23,470 $ — $ — $ — $ — $ — $ — Agency MBS — 2,409,521 — — — — — — Agency CMBS — 3,625,627 — — — — — — Municipal bonds and notes 333,479 162,615 253,671 115,404 32,732 — 4,165 14,038 CMBS 100,075 — — — — — — — Total held-to-maturity $ 433,554 $ 6,221,233 $ 253,671 $ 115,404 $ 32,732 $ — $ 4,165 $ 14,038 At December 31, 2022 Investment Grade (In thousands) Aaa Aa1 Aa2 Aa3 A1 A2 A3 Not Rated Agency CMOs $ — $ 28,358 $ — $ — $ — $ — $ — $ — Agency MBS — 2,626,114 — — — — — — Agency CMBS — 2,831,949 — — — — — — Municipal bonds and notes 336,035 163,312 255,235 116,870 38,177 4,165 — 15,051 CMBS 149,613 — — — — — — — Total held-to-maturity $ 485,648 $ 5,649,733 $ 255,235 $ 116,870 $ 38,177 $ 4,165 $ — $ 15,051
Schedule of Realized Gain (Loss)

Loans and Leases (Tables)

Loans and Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Loans and Leases Receivable Disclosure [Abstract]
Loans and Leases by Portfolio Segment and Class	The following table summarizes loans and leases by portfolio segment and class: At December 31, (In thousands) 2023 2022 Commercial non-mortgage $ 16,885,475 $ 16,392,795 Asset-based 1,557,841 1,821,642 Commercial real estate 13,569,762 12,997,163 Multi-family 7,587,970 6,621,982 Equipment financing 1,328,786 1,628,393 Warehouse lending — 641,976 Commercial portfolio 40,929,834 40,103,951 Residential 8,227,923 7,963,420 Home equity 1,516,955 1,633,107 Other consumer 51,340 63,948 Consumer portfolio 9,796,218 9,660,475 Loans and leases $ 50,726,052 $ 49,764,426
Past Due Financing Receivables	Non-Accrual and Past Due Loans and Leases The following tables summarize the aging of accrual and non-accrual loans and leases by class: At December 31, 2023 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Current Total Loans Commercial non-mortgage $ 2,270 $ 890 $ 94 $ 122,855 $ 126,109 $ 16,759,366 $ 16,885,475 Asset-based — — — 35,068 35,068 1,522,773 1,557,841 Commercial real estate 1,459 — 184 11,383 13,026 13,556,736 13,569,762 Multi-family 5,198 2,340 — — 7,538 7,580,432 7,587,970 Equipment financing 3,966 8 — 9,828 13,802 1,314,984 1,328,786 Commercial portfolio 12,893 3,238 278 179,134 195,543 40,734,291 40,929,834 Residential 14,894 6,218 — 5,704 26,816 8,201,107 8,227,923 Home equity 5,676 3,285 — 23,545 32,506 1,484,449 1,516,955 Other consumer 410 94 — 142 646 50,694 51,340 Consumer portfolio 20,980 9,597 — 29,391 59,968 9,736,250 9,796,218 Total $ 33,873 $ 12,835 $ 278 $ 208,525 $ 255,511 $ 50,470,541 $ 50,726,052 At December 31, 2022 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Current (1) Total Loans Commercial non-mortgage $ 8,434 $ 821 $ 645 $ 71,884 $ 81,784 $ 16,311,011 $ 16,392,795 Asset-based 5,921 — — 20,024 25,945 1,795,697 1,821,642 Commercial real estate 1,494 23,492 68 39,057 64,111 12,933,052 12,997,163 Multi-family 1,157 — — 636 1,793 6,620,189 6,621,982 Equipment financing 806 9,988 — 12,344 23,138 1,605,255 1,628,393 Warehouse Lending — — — — — 641,976 641,976 Commercial portfolio 17,812 34,301 713 143,945 196,771 39,907,180 40,103,951 Residential 8,246 3,083 — 25,424 36,753 7,926,667 7,963,420 Home equity 5,293 2,820 — 27,924 36,037 1,597,070 1,633,107 Other consumer 1,028 85 13 148 1,274 62,674 63,948 Consumer portfolio 14,567 5,988 13 53,496 74,064 9,586,411 9,660,475 Total $ 32,379 $ 40,289 $ 726 $ 197,441 $ 270,835 $ 49,493,591 $ 49,764,426 (1) At December 31, 2022, there were $28.5 million of commercial loans that had reached their contractual maturity but were actively in the process of being refinanced with the Company. Due to the status of the refinancing, these commercial loans have been reported as current in the table above. The following table provides additional information on non-accrual loans and leases: At December 31, 2023 2022 (In thousands) Non-accrual Non-accrual With No Allowance Non-accrual Non-accrual With No Allowance Commercial non-mortgage $ 122,855 $ 20,066 $ 71,884 $ 12,598 Asset-based 35,068 1,330 20,024 1,491 Commercial real estate 11,383 2,681 39,057 90 Multi-family — — 636 — Equipment financing 9,828 1,584 12,344 2,240 Commercial portfolio 179,134 25,661 143,945 16,419 Residential 5,704 856 25,424 10,442 Home equity 23,545 12,471 27,924 15,193 Other consumer 142 49 148 5 Consumer portfolio 29,391 13,376 53,496 25,640 Total $ 208,525 $ 39,037 $ 197,441 $ 42,059
Activity In Allowance For Losses	Allowance for Credit Losses on Loans and Leases The following tables summarize the change in the ACL on loans and leases by portfolio segment: At or for the Years ended December 31, 2023 2022 2021 (In thousands) Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total ACL on loans and leases: Balance, beginning of period $ 533,125 $ 61,616 $ 594,741 $ 257,877 $ 43,310 $ 301,187 $ 312,244 $ 47,187 $ 359,431 Adoption of ASU No. 2022-02 7,704 (1,831) 5,873 — — — — — — Initial allowance for PCD loans and leases (1) — — — 78,376 9,669 88,045 — — — Provision (benefit) 138,057 5,152 143,209 268,295 4,502 272,797 (48,651) (5,764) (54,415) Charge-offs (104,509) (12,703) (117,212) (82,860) (4,662) (87,522) (9,437) (9,217) (18,654) Recoveries 3,286 5,840 9,126 11,437 8,797 20,234 3,721 11,104 14,825 Balance, end of period $ 577,663 $ 58,074 $ 635,737 $ 533,125 $ 61,616 $ 594,741 $ 257,877 $ 43,310 $ 301,187 Individually evaluated for credit losses 43,559 4,635 48,194 34,793 12,441 47,234 16,965 4,108 21,073 Collectively evaluated for credit losses $ 534,104 $ 53,439 $ 587,543 $ 498,332 $ 49,175 $ 547,507 $ 240,912 $ 39,202 $ 280,114 (1) Represents the establishment of the initial reserve for PCD loans and leases, which is reported net of $48.3 million of day one charge-offs recognized at the date of acquisition in accordance with GAAP.
Financing Receivable Credit Quality Indicators	The following tables summarize the amortized cost basis of commercial loans and leases by Composite Credit Risk Profile grade and origination year: At December 31, 2023 (In thousands) 2023 2022 2021 2020 2019 Prior Revolving Loans Amortized Cost Basis Total Commercial non-mortgage: Risk rating: Pass $ 2,602,444 $ 4,089,327 $ 1,371,139 $ 711,362 $ 610,199 $ 952,097 $ 5,970,588 $ 16,307,156 Special mention 15,184 60,240 61,235 33,111 — 720 48,561 219,051 Substandard 48,849 104,087 23,258 28,222 44,612 30,426 79,778 359,232 Doubtful — 8 — — 3 25 — 36 Total commercial non-mortgage 2,666,477 4,253,662 1,455,632 772,695 654,814 983,268 6,098,927 16,885,475 Current period gross write-offs 325 7,637 1,775 512 969 4,391 — 15,609 Asset-based: Risk rating: Pass 23,007 — — — 3,280 34,999 1,333,271 1,394,557 Special mention 651 763 — — 3,676 — 29,610 34,700 Substandard — — — — 1,330 — 127,254 128,584 Total asset-based 23,658 763 — — 8,286 34,999 1,490,135 1,557,841 Current period gross write-offs — — — — 13,189 3,900 — 17,089 Commercial real estate: Risk rating: Pass 2,265,428 3,502,425 1,831,005 1,195,732 1,193,642 3,112,770 176,668 13,277,670 Special mention 850 4,675 14,463 31,405 23,443 37,688 1,210 113,734 Substandard 25,802 16,179 9,545 15,418 58,602 52,812 — 178,358 Total commercial real estate 2,292,080 3,523,279 1,855,013 1,242,555 1,275,687 3,203,270 177,878 13,569,762 Current period gross write-offs 4,632 — 12,617 3,813 2,754 38,569 — 62,385 Multi-family: Risk rating: Pass 1,597,599 1,934,100 1,041,416 442,888 595,676 1,920,618 — 7,532,297 Special mention — — — — 260 35,942 — 36,202 Substandard — — — 364 11,563 7,544 — 19,471 Total multi-family 1,597,599 1,934,100 1,041,416 443,252 607,499 1,964,104 — 7,587,970 Current period gross write-offs — — — — — 3,447 — 3,447 Equipment financing: Risk rating: Pass 335,874 297,186 232,304 176,061 183,679 69,927 — 1,295,031 Special mention — — 116 — 90 — — 206 Substandard — 9,144 8,064 6,600 4,285 5,456 — 33,549 Total equipment financing 335,874 306,330 240,484 182,661 188,054 75,383 — 1,328,786 Current period gross write-offs — — — 2,633 3,304 42 — 5,979 Total commercial portfolio $ 6,915,688 $ 10,018,134 $ 4,592,545 $ 2,641,163 $ 2,734,340 $ 6,261,024 $ 7,766,940 $ 40,929,834 Current period gross write-offs $ 4,957 $ 7,637 $ 14,392 $ 6,958 $ 20,216 $ 50,349 $ — $ 104,509 At December 31, 2022 (In thousands) 2022 2021 2020 2019 2018 Prior Revolving Loans Amortized Cost Basis Total Commercial non-mortgage: Pass $ 5,154,781 $ 1,952,158 $ 965,975 $ 792,977 $ 593,460 $ 780,200 $ 5,670,532 $ 15,910,083 Special mention 104,277 15,598 21,168 263 14,370 7,770 40,142 203,588 Substandard 28,203 11,704 69,954 36,604 70,634 16,852 41,917 275,868 Doubtful — — — 1 — — 3,255 3,256 Total commercial non-mortgage 5,287,261 1,979,460 1,057,097 829,845 678,464 804,822 5,755,846 16,392,795 Asset-based: Pass 19,659 3,901 9,424 14,413 5,163 55,553 1,551,250 1,659,363 Special mention — — — — — — 80,476 80,476 Substandard — — — 1,491 — — 80,312 81,803 Total asset-based 19,659 3,901 9,424 15,904 5,163 55,553 1,712,038 1,821,642 Commercial real estate: Pass 3,420,635 2,246,672 1,556,185 1,605,869 1,058,730 2,681,052 97,832 12,666,975 Special mention 21,878 8,995 7,264 37,570 47,419 66,652 1,000 190,778 Substandard 519 2,459 216 31,163 47,021 57,997 — 139,375 Doubtful — — — 1 — 34 — 35 Total commercial real estate 3,443,032 2,258,126 1,563,665 1,674,603 1,153,170 2,805,735 98,832 12,997,163 Multi-family: Pass 1,992,980 1,057,705 507,065 694,066 444,564 1,748,337 51,655 6,496,372 Special mention 37,677 — — 95 40,307 726 8,838 87,643 Substandard — — 382 — 12,681 24,904 — 37,967 Total multi-family 2,030,657 1,057,705 507,447 694,161 497,552 1,773,967 60,493 6,621,982 Equipment financing: Pass 388,641 345,792 331,419 308,441 98,874 83,264 — 1,556,431 Special mention — 185 — 11,965 6,775 25 — 18,950 Substandard 314 16,711 18,436 5,016 5,307 7,228 — 53,012 Total equipment financing 388,955 362,688 349,855 325,422 110,956 90,517 — 1,628,393 Warehouse lending: Pass — — — — — — 641,976 641,976 Total warehouse lending — — — — — — 641,976 641,976 Total commercial portfolio $ 11,169,564 $ 5,661,880 $ 3,487,488 $ 3,539,935 $ 2,445,305 $ 5,530,594 $ 8,269,185 $ 40,103,951 The following tables summarize the amortized cost basis of consumer loans by FICO score and origination year: At December 31, 2023 (In thousands) 2023 2022 2021 2020 2019 Prior Revolving Loans Amortized Cost Basis Total Residential: Risk rating: 800+ $ 214,446 $ 847,009 $ 1,096,109 $ 451,307 $ 141,919 $ 910,117 $ — $ 3,660,907 740-799 363,696 703,568 755,750 279,946 112,303 633,578 — 2,848,841 670-739 137,460 293,699 292,255 95,838 48,412 346,663 — 1,214,327 580-669 20,208 52,962 45,770 14,840 10,492 106,497 — 250,769 579 and below 6,909 52,690 11,749 1,345 128,714 51,672 — 253,079 Total residential 742,719 1,949,928 2,201,633 843,276 441,840 2,048,527 — 8,227,923 Current period gross write-offs — — 387 — 153 4,630 — 5,170 Home equity: Risk rating: 800+ 27,047 27,439 35,927 25,586 8,110 56,062 391,616 571,787 740-799 24,772 20,069 27,147 13,888 5,158 34,190 355,926 481,150 670-739 15,857 15,655 15,389 5,992 3,189 29,454 242,189 327,725 580-669 3,080 3,786 1,991 1,658 1,115 9,988 70,102 91,720 579 and below 696 1,109 1,079 576 552 6,319 34,242 44,573 Total home equity 71,452 68,058 81,533 47,700 18,124 136,013 1,094,075 1,516,955 Current period gross write-offs — 4 81 — 104 3,114 — 3,303 Other consumer: Risk rating: 800+ 432 356 1,913 189 255 77 25,699 28,921 740-799 1,318 586 486 730 690 381 7,180 11,371 670-739 526 570 358 981 1,210 79 3,549 7,273 580-669 69 169 129 153 303 56 1,983 2,862 579 and below 125 97 61 11 28 1 590 913 Total other consumer 2,470 1,778 2,947 2,064 2,486 594 39,001 51,340 Current period gross write-offs 3,263 7 2 218 377 363 — 4,230 Total consumer portfolio 816,641 2,019,764 2,286,113 893,040 462,450 2,185,134 1,133,076 9,796,218 Current period gross write-offs $ 3,263 $ 11 $ 470 $ 218 $ 634 $ 8,107 $ — $ 12,703 At December 31, 2022 (In thousands) 2022 2021 2020 2019 2018 Prior Revolving Loans Amortized Cost Basis Total Residential: 800+ $ 527,408 $ 954,568 $ 469,518 $ 160,596 $ 28,361 $ 997,409 $ — $ 3,137,860 740-799 963,026 946,339 311,295 111,913 43,684 689,771 — 3,066,028 670-739 381,515 350,671 103,999 62,365 18,451 384,687 — 1,301,688 580-669 40,959 49,648 14,484 5,836 2,357 138,107 — 251,391 579 and below 52,464 3,693 2,057 84,032 1,299 62,908 — 206,453 Total residential 1,965,372 2,304,919 901,353 424,742 94,152 2,272,882 — 7,963,420 Home equity: 800+ 25,475 35,129 25,612 7,578 12,545 55,352 465,318 627,009 740-799 26,743 35,178 17,621 8,111 7,765 32,270 398,692 526,380 670-739 18,396 16,679 8,175 3,635 7,614 30,060 259,646 344,205 580-669 2,848 3,068 1,520 1,456 1,163 13,607 76,614 100,276 579 and below 426 386 651 661 563 4,736 27,814 35,237 Total home equity 73,888 90,440 53,579 21,441 29,650 136,025 1,228,084 1,633,107 Other consumer: 800+ 495 218 544 1,045 247 56 19,196 21,801 740-799 888 2,624 1,959 2,494 941 364 12,218 21,488 670-739 977 603 2,480 4,238 1,041 118 6,107 15,564 580-669 211 117 337 801 173 54 2,223 3,916 579 and below 169 101 29 116 36 21 707 1,179 Total other consumer 2,740 3,663 5,349 8,694 2,438 613 40,451 63,948 Total consumer portfolio 2,042,000 2,399,022 960,281 454,877 126,240 2,409,520 1,268,535 9,660,475 Modifications to Borrowers Experiencing Financial Difficulty On January 1, 2023, the Company adopted ASU 2022-02, which eliminated the accounting guidance for TDRs and enhanced the disclosure requirements for certain loan modifications when a borrower is experiencing financial difficulty. For a description of the Company's accounting policies related to the accounting and reporting of TDRs, for which comparative period information is presented, refer to Note 1: Summary of Significant Accounting Policies. In certain circumstances, the Company enters into agreements to modify the terms of loans to borrowers experiencing financial difficulty. A variety of solutions are offered to borrowers experiencing financial difficulty, including loan modifications that may result in principal forgiveness, interest rate reductions, payment delays, term extension, or a combination thereof. The following is a description of each of these types of modifications: • Principal forgiveness – The outstanding principal balance of a loan may be reduced by a specified amount. Principal forgiveness may occur voluntarily as part of a negotiated agreement with a borrower, or involuntarily through a bankruptcy proceeding. • Interest rate reductions – Includes modifications where the contractual interest rate of the loan has been reduced. • Payment delays – Deferral arrangements that allow borrowers to delay a scheduled loan payment to a later date. Deferred loan payments do not affect the original contracted maturity terms of the loan. Modifications that result in only an insignificant payment delay are not disclosed. The Company generally considers a payment delay of three months or less to be insignificant. • Term extensions – Extensions of the original contractual maturity date of the loan. • Combination – Combination includes loans that have undergone more than one of the above loan modification types. Significant judgment is required to determine if a borrower is experiencing financial difficulty. These considerations vary by portfolio class. The Company has identified modifications to borrowers experiencing financial difficulty that are included in its disclosures as follows: • Commercial: The Company evaluates modifications of loans to commercial borrowers that are rated substandard or worse, and includes the modification in its disclosures to the extent that the modification is considered • Consumer: The Company generally evaluates all modifications of loans to consumer borrowers subject to its loss mitigation program and includes them in its disclosures to the extent that the modification is considered other-than-insignificant. The following table summarizes the amortized cost basis at December 31, 2023, of loans modified to borrowers experiencing financial difficulty, disaggregated by class and type of concession granted: For the year ended December 31, 2023 (In thousands) Interest Rate Reduction Term Extension Payment Delay CombinationTerm Extension & Interest Rate Reduction CombinationTerm Extension & Payment Delay CombinationInterest Rate Reduction & Payment Delay CombinationTerm Extension, Interest Rate Reduction, & Payment Delay Total % of Total Class (2) Commercial non-mortgage $ — $ 96,895 $ 5,858 $ 1,062 $ 28,860 $ 35 $ 425 $ 133,135 0.8 % Asset-based — 45,042 — — — — — 45,042 2.9 Commercial real estate — 3,090 174 17,107 511 — — 20,882 0.2 Equipment financing — 357 1,284 — — — — 1,641 0.1 Residential — 186 804 136 — — — 1,126 — Home equity 62 76 — 513 — — — 651 — Total (1) $ 62 $ 145,646 $ 8,120 $ 18,818 $ 29,371 $ 35 $ 425 $ 202,477 0.4 % (1) The total amortized cost excludes accrued interest receivable of $0.7 million for the year ended December 31, 2023. (2) Represents the total amortized cost of the loans modified as a percentage of the total period end loan balance by class. The following table describes the financial effect of the modifications made to borrowers experiencing financial difficulty: For the year ended December 31, 2023 Financial Effect Interest Rate Reduction: Home equity Reduced weighted average interest rate by 0.5% Term Extension: Commercial non-mortgage Extended term by a weighted average of 1.3 years Asset-based Extended term by a weighted average of 0.7 years Commercial real estate Extended term by a weighted average of 2.2 years Equipment financing Extended term by a weighted average of 4.5 years Residential Extended term by a weighted average of 2.8 years Home equity Extended term by a weighted average of 10.1 years Payment Delay: Commercial non-mortgage Provided partial payment deferrals for a weighted average of 0.5 years Commercial real estate Provided payment deferrals for a weighted average of 0.3 years to be received at contractual maturity Equipment financing Provided partial payment deferrals for a weighted average of 0.5 years Residential Provided payment deferrals for a weighted average of 1.0 year Combination Term Extension & Interest Rate Reduction: Commercial non-mortgage Extended term by a weighted average of 1.4 years and reduced weighted average interest rate by 1.8% Commercial real estate Extended term by a weighted average of 3.0 years and reduced weighted average interest rate by 2.4% Residential Extended term by a weighted average of 17.9 years and reduced weighted average interest rate by 0.3% Home equity Extended term by a weighted average of 16.8 years and reduced weighted average interest rate by 2.1% Combination Term Extension & Payment Delay: Commercial non-mortgage Extended term by a weighted average of 1.1 years and provided partial payment deferrals for a weighted average of 1.0 year Commercial real estate Extended term by a weighted average of 0.5 years and provided payment deferrals for a weighted average of 0.5 years Combination Interest Rate Reduction & Payment Delay: Commercial non-mortgage Reduced weighted average interest rate by 2.0% and provided payment deferrals for a weighted average of 0.5 years Combination Term Extension, Interest Rate Reduction, & Payment Delay: Commercial non-mortgage Extended term by a weighted average of 0.5 years, reduced weighted average interest rate by 2.0%, and provided payment deferrals for a weighted average of 0.5 years The Company closely monitors the performance of the loans that are modified to borrowers experiencing financial difficulty to understand the effectiveness of its modification efforts. The following table summarizes the aging of loans that have been modified in the year ended December 31, 2023: At December 31, 2023 (In thousands) Current 30-59 Days 60-89 Days 90+ Days Non-Accrual Total Commercial non-mortgage $ 107,852 $ — $ — $ — $ 25,283 $ 133,135 Asset-based 45,042 — — — — 45,042 Commercial real estate 20,708 — — — 174 20,882 Equipment financing 1,284 — — — 357 1,641 Residential 990 — — — 136 1,126 Home equity 547 — — — 104 651 Total $ 176,423 $ — $ — $ — $ 26,054 $ 202,477
Troubled Debt Restructurings on Financing Receivables	Troubled Debt Restructurings Prior to the Adoption of ASU 2022-02 The following table summarizes information related to TDRs: (In thousands) At December 31, 2022 Accrual status $ 110,868 Non-accrual status 83,954 Total TDRs $ 194,822 Additional funds committed to borrowers in TDR status $ 1,724 Specific reserves for TDRs included in the ACL on loans and leases: Commercial portfolio $ 14,578 Consumer portfolio 3,559 The following table summarizes loans and leases modified as TDRs by class and modification type: Years ended December 31, 2022 2021 Number of Recorded Investment (1) Number of Recorded Investment (1) (Dollars in thousands) Commercial non-mortgage: Extended maturity 5 $ 291 8 $ 605 Maturity / rate combined 8 765 9 352 Other (2) 19 52,070 12 14,160 Asset-based: Other (2) 1 23,298 — — Commercial real estate: Extended maturity — — 1 183 Other (2) — — 1 1,582 Equipment financing: Other (2) 3 1,692 — — Residential: Extended maturity 2 1,185 1 99 Maturity / rate combined 2 133 2 401 Other (2) 8 3,158 3 280 Home equity: Extended maturity — — 85 1,809 Adjusted interest rate 1 74 — — Maturity / rate combined 21 2,623 6 1,025 Other (2) 37 2,134 22 1,481 Total TDRs 107 $ 87,423 150 $ 21,977 (1) Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs due to restructurings was not significant. (2) Other includes covenant modifications, forbearance, discharges under Chapter 7 bankruptcy, or other concessions.

Transfers of Financial Assets (

Transfers of Financial Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Transfers and Servicing [Abstract]
Schedule of Loan Sale Activity [Table Text Block]	The following table summarizes information related to mortgage banking activities: Years ended December 31, (In thousands) 2023 2022 2021 Net gain on sale $ 1,126 $ 580 $ 5,192 Origination fees 68 219 1,440 Fair value adjustments 46 (94) (413) Mortgage banking activities $ 1,240 $ 705 $ 6,219 Proceeds from sale $ 13,882 $ 36,335 $ 247,634 Loans sold with servicing rights retained 6,499 32,056 237,834
Servicing Asset at Amortized Cost	The following table presents the change in the carrying amount for mortgage servicing rights: Years ended December 31, (In thousands) 2023 2022 2021 Balance, beginning of period $ 9,515 $ 9,237 $ 13,422 Acquired from Sterling — 859 — Additions 71 289 2,053 Amortization (1) (1,063) (870) (5,593) Adjustment to valuation allowance — — (645) Balance, end of period $ 8,523 $ 9,515 $ 9,237 (1) The Company implemented a change in the method of amortization applied to its mortgage servicing rights during the year ended December 31, 2022, to better reflect the pattern of consumption, where estimated future cash flows are now assessed at the individual loan level as opposed to on a pooled basis.

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property and equipment is carried at cost, less accumulated depreciation and amortization. Depreciation and amortization is computed on a straight-line basis over the estimated useful lives of the assets, as illustrated in the following table. If shorter, leasehold improvements are amortized over the terms of the respective leases. Minimum Maximum Building and improvements 5 - 40 years Leasehold improvements 5 - 20 years Furniture, fixtures, and equipment 5 - 10 years Data processing equipment and software 3 - 7 years The following table summarizes the components of premises and equipment: At December 31, (In thousands) 2023 2022 Land $ 73,916 $ 73,916 Buildings and improvements 107,794 106,180 Leasehold improvements 88,065 84,477 Furniture, fixtures, and equipment 68,680 71,542 Data processing equipment and software 94,030 128,153 Property and equipment 432,485 464,268 Less: Accumulated depreciation and amortization (186,365) (225,152) Property and equipment, net 246,120 239,116 ROU lease assets, net 183,441 191,068 Premises and equipment, net $ 429,561 $ 430,184

Leasing (Tables)

Leasing (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Summary of Net Investments	The following table summarizes the components of the Company's net investment in its sales-type and direct financing leases: At December 31, (In thousands) 2023 2022 Lease receivables $ 347,827 $ 330,690 Unguaranteed residual values 60,747 100,368 Total net investment $ 408,574 $ 431,058
Summary of Net Investment Maturity	The following table reconciles undiscounted future lease payments to the total sales-type and direct financing leases' net investment: (In thousands) At December 31, 2023 2024 $ 116,506 2025 107,211 2026 98,157 2027 51,058 2028 31,179 Thereafter 44,911 Total lease payments receivable 449,022 Present value adjustment (40,448) Total net investment $ 408,574
Schedule of Components of Leveraged Lease Investments	The following table summarizes the Company's ROU lease assets and operating lease liabilities: At December 31, (In thousands) Consolidated Balance Sheet Line Item 2023 2022 ROU lease assets Premises and equipment, net $ 183,441 $ 191,068 Operating lease liabilities Accrued expenses and other liabilities 222,439 239,281
Lease, Cost	The following table summarizes the components of operating lease expense and other relevant information: At or for the Years ended December 31, (In thousands) 2023 2022 2021 Lease Cost: Operating and variable lease costs $ 38,497 $ 44,654 $ 30,936 Sublease income (223) (1,383) (554) Total operating lease expense $ 38,274 $ 43,271 $ 30,382 Other Information: Cash paid for amounts included in the measurement of operating lease liabilities $ 37,615 $ 44,767 $ 30,487 ROU lease assets obtained in exchange for operating lease liabilities (1) 22,989 27,897 15,226 Weighted-average remaining lease term (in years) 7.46 7.72 7.50 Weighted-average discount rate 2.96 % 2.65 % 3.04 % (1) The amount for the year ended December 31, 2022, excludes ROU lease assets acquired from Sterling in the merger.
Lessee, Operating Lease, Liability, Maturity	The following table reconciles undiscounted future lease payments to total operating lease liabilities: (In thousands) At December 31, 2023 2024 $ 38,575 2025 39,449 2026 35,665 2027 31,128 2028 26,999 Thereafter 81,918 Total operating lease payments 253,734 Present value adjustment (31,295) Total operating lease liabilities $ 222,439

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table summarizes changes in the carrying amount of goodwill: At December 31, (In thousands) 2023 2022 Balance, beginning of period $ 2,514,104 $ 538,373 interLINK acquisition 143,216 — Sterling merger (1) (25,561) 1,939,765 Bend acquisition (1) (294) 35,966 Balance, end of period $ 2,631,465 $ 2,514,104
Schedule of Finite-Lived Intangible Assets	The following table summarizes other intangible assets: At December 31, 2023 2022 (In thousands) Gross Carrying Amount (1) Accumulated Net Carrying Gross Carrying Accumulated Net Carrying Core deposits $ 146,037 $ 53,986 $ 92,051 $ 146,037 $ 36,710 $ 109,327 Customer relationships (1) 151,000 43,116 107,884 115,000 24,985 90,015 Non-competition agreement (1) 4,000 800 3,200 — — — Other intangible assets $ 301,037 $ 97,902 $ 203,135 $ 261,037 $ 61,695 $ 199,342 (1) The increase in the gross carrying amount is attributed to the acquisition of interLINK during the first quarter of 2023, in which the Company identified and recorded a $36.0 million intangible asset for broker dealer relationships, which is being amortized on an accelerated basis over an estimated useful life of 10 years, and a $4.0 million non-competition agreement, which is being amortized on a straight-line basis over an estimated useful life of 5 years.
Schedule Of Expected Amortization Expense, Next Four Years	is as follows: (In thousands) At December 31, 2024 $ 29,618 2025 25,956 2026 25,565 2027 25,565 2028 23,216 Thereafter 73,215

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	Income tax expense reflects the following expense (benefit) components: Years ended December 31, (In thousands) 2023 2022 2021 Current: Federal $ 219,548 $ 170,779 $ 109,621 State and local 50,750 52,579 20,374 Total current 270,298 223,358 129,995 Deferred: Federal (43,615) (45,421) (9,844) State and local (10,019) (24,243) 4,846 Total deferred (53,634) (69,664) (4,998) Total federal 175,933 125,358 99,777 Total state and local 40,731 28,336 25,220 Income tax expense $ 216,664 $ 153,694 $ 124,997
Schedule of Effective Income Tax Rate Reconciliation	The following table reflects a reconciliation of reported income tax expense to the amount that would result from applying the federal statutory rate of 21.0%: Years ended December 31, 2023 2022 2021 (In thousands) Amount Percent Amount Percent Amount Percent Income tax expense at federal statutory rate $ 227,746 21.0 % $ 167,575 21.0 % $ 112,111 21.0 % Reconciliation to reported income tax expense: SALT expense, net of federal 32,177 3.0 32,259 4.1 19,924 3.7 Tax-exempt interest income, net (44,473) (4.1) (35,371) (4.4) (6,814) (1.3) Increase in cash surrender value of life insurance (5,469) (0.5) (6,122) (0.8) (3,030) (0.6) Non-deductible FDIC deposit insurance premiums 10,693 1.0 5,581 0.7 2,064 0.4 Low income housing tax credits and other benefits, net (3,866) (0.4) (7,627) (1.0) (615) (0.1) Non-deductible compensation expense 4,167 0.4 7,948 1.0 786 0.1 Non-deductible merger-related expenses, excluding compensation 45 — 2,717 0.3 3,451 0.7 DTA valuation allowance adjustment, net (368) — (9,874) (1.2) — — Other, net (3,988) (0.4) (3,392) (0.4) (2,880) (0.5) Income tax expense and effective tax rate $ 216,664 20.0 % $ 153,694 19.3 % $ 124,997 23.4 %
Schedule of Deferred Tax Assets and Liabilities	The following table reflects the significant components of DTAs, net: At December 31, (In thousands) 2023 2022 Deferred tax assets: ACL on loans and leases $ 171,870 $ 161,932 Net operating loss and credit carry forwards 68,103 72,035 Compensation and employee benefit plans 46,670 55,093 Lease liabilities under operating leases 60,331 64,899 Net unrealized loss on available-for-sale securities 191,922 233,978 Other 72,546 38,314 Gross deferred tax assets 611,442 626,251 Valuation allowance (28,746) (29,176) Total deferred tax assets, net of valuation allowance $ 582,696 $ 597,075 Deferred tax liabilities: ROU assets under operating leases $ 49,754 $ 51,822 Equipment financing leases 54,300 74,295 Goodwill and other intangible assets 59,817 56,223 Purchase accounting and fair value adjustments 15,527 11,529 Other 34,086 31,572 Gross deferred tax liabilities 213,484 225,441 Deferred tax assets, net $ 369,212 $ 371,634
Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible	The following table reflects a reconciliation of the beginning and ending balances of UTBs: Years ended December 31, (In thousands) 2023 2022 2021 Beginning balance $ 9,875 $ 4,249 $ 4,252 Additions as a result of tax positions taken during the current year 359 223 294 Additions as a result of tax positions taken during prior years 4,255 8,807 434 Reductions as a result of tax positions taken during prior years — (503) (186) Reductions relating to settlements with taxing authorities — (2,110) (267) Reductions as a result of lapse of statute of limitation periods (653) (791) (278) Ending balance $ 13,836 $ 9,875 $ 4,249

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2023
Deposit Liabilities [Abstract]
Deposit Liabilities, Type [Table Text Block]	The following table summarizes deposits by type: At December 31, (In thousands) 2023 2022 Non-interest-bearing: Demand $ 10,732,516 $ 12,974,975 Interest-bearing: Health savings accounts 8,287,889 7,944,892 Checking 8,994,095 9,237,529 Money market 17,662,826 11,062,652 Savings 6,642,499 8,673,343 Time deposits 8,464,459 4,160,949 Total interest-bearing 50,051,768 41,079,365 Total deposits $ 60,784,284 $ 54,054,340 Time deposits, money market, and interest-bearing checking obtained through brokers (1) $ 3,673,733 $ 1,964,873 Aggregate amount of time deposit accounts that exceeded the FDIC limit 1,221,887 1,894,950 Demand deposit overdrafts reclassified as loan balances 10,432 8,721 (1) Excludes $5.7 billion of interLINK money market sweep deposits at December 31, 2023.
Time Deposit Maturities [Table Text Block]	The following table summarizes the scheduled maturities of time deposits: (In thousands) At December 31, 2023 2024 $ 8,217,683 2025 138,769 2026 53,807 2027 32,865 2028 21,335 Total time deposits $ 8,464,459

Borrowings (Tables)

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Schedule of Repurchase Agreements	The following table summarizes securities sold under agreements to repurchase and other borrowings: At December 31, 2023 2022 (In thousands) Total Outstanding Rate Total Outstanding Rate Securities sold under agreements to repurchase (1) $ 358,387 3.43 % $ 282,005 0.11 % Federal funds purchased 100,000 5.48 869,825 4.44 Securities sold under agreements to repurchase and other borrowings $ 458,387 3.88 % $ 1,151,830 3.38 % (1) The Company has the right of offset with respect to all repurchase agreement assets and liabilities. Total securities sold under agreements to repurchase are presented as gross transactions, as only liabilities are outstanding for the periods presented. Securities sold under agreements to repurchase, all of which have an original maturity of one year or less for the periods presented, are used as a source of borrowed funds and are collateralized by Agency MBS and Corporate debt. The Company's repurchase agreement counterparties are limited to primary dealers in government securities, and commercial and municipal customers through the Corporate Treasury function. The Company may also purchase unsecured term and overnight federal funds to satisfy its short-term liquidity needs.
Federal Home Loan Bank, Advances	The following table summarizes information for FHLB advances: At December 31, 2023 2022 (In thousands) Total Weighted-Average Contractual Coupon Rate Total Weighted-Average Contractual Coupon Rate Maturing within 1 year $ 2,350,000 5.53 % $ 5,450,187 4.40 % After 1 but within 2 years — — — — After 2 but within 3 years — — — — After 3 but within 4 years 235 — — — After 4 but within 5 years 228 2.75 252 — After 5 years 9,555 2.07 10,113 2.09 FHLB advances $ 2,360,018 5.52 % $ 5,460,552 4.39 % Aggregate market value of assets pledged as collateral $ 20,734,035 $ 13,692,379 Remaining borrowing capacity at FHLB 12,535,423 4,291,326 The Bank may borrow up to the amount of eligible mortgages and securities that have been pledged as collateral to secure FHLB advances, which includes certain residential and commercial real estate loans, home equity lines of credit, CMBS, Agency MBS, Agency CMO, and U.S. Treasury notes. The Bank was in compliance with its FHLB collateral requirements at both December 31, 2023, and 2022.
Schedule of Long-Term Debt	The following table summarizes long-term debt: At December 31, (In thousands) 2023 2022 4.375% Senior fixed-rate notes due February 15, 2024 (2) $ 132,550 $ 150,000 4.100 % Senior fixed-rate notes due March 25, 2029 (3) 328,104 333,458 4.000% Subordinated fixed-to-floating rate notes due December 30, 2029 274,000 274,000 3.875 % Subordinated fixed-to-floating rate notes due November 1, 2030 225,000 225,000 Junior subordinated debt Webster Statutory Trust I floating-rate notes due September 17, 2033 (4) 77,320 77,320 Total senior and subordinated debt 1,036,974 1,059,778 Discount on senior fixed-rate notes (537) (756) Debt issuance cost on senior fixed-rate notes (1,419) (1,824) Premium on subordinated fixed-to-floating rate notes 13,802 15,930 Long-term debt (1) $ 1,048,820 $ 1,073,128 (1) The classification of debt as long-term is based on the initial terms of greater than one year as of the date of issuance. (2) The Company repurchased and retired $17.5 million of these senior notes at 96 cents on the dollar in May 2023. The resulting (3) The Company de-designated its fair value hedging relationship on these senior notes in 2020. A basis adjustment of $28.1 million and $33.5 million at December 31, 2023, and 2022, respectively, is included in the carrying value and is being amortized over the remaining life of the senior notes. (4) The interest rate on the Webster Statutory Trust I floating-rate notes varies quarterly based on 3-month SOFR plus a credit spread adjustment plus a market spread of 2.95%. Prior to LIBOR cessation on July 1, 2023, the notes varied quarterly based on 3-month LIBOR plus a market spread of 2.95%. The interest rates yielded 8.59% and 7.69% at December 31, 2023, and 2022, respectively.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Schedule of Stock by Class	The following table summarizes the changes in shares of preferred and common stock issued and common stock held as treasury shares for the year ended December 31, 2023: Preferred Stock Series F Issued Preferred Stock Series G Issued Common Stock Issued Treasury Stock Held Common Stock Outstanding Balance, beginning of period 6,000 135,000 182,778,045 8,770,472 174,007,573 Restricted stock compensation plan activity — — — (605,684) 605,684 Stock options exercised — — — (75,848) 75,848 Common stock repurchase program — — 2,667,149 (2,667,149) Balance, end of period 6,000 135,000 182,778,045 10,756,089 172,021,956

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss, Net of Tax (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [Abstract]
Schedule of Other Comprehensive Income (Loss)	The following table summarizes the changes in each component of accumulated other comprehensive (loss) income, net of tax: (In thousands) Investment Securities Available- Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Balance at December 31, 2020 $ 67,424 $ 19,918 $ (45,086) $ 42,256 Other comprehensive (loss) income before reclassifications (62,888) (17,109) 8,876 (71,121) Amounts reclassified from accumulated other comprehensive — 3,261 3,024 6,285 Other comprehensive (loss) income, net of tax (62,888) (13,848) 11,900 (64,836) Balance at December 31, 2021 4,536 6,070 (33,186) (22,580) Other comprehensive (loss) before reclassifications (640,656) (17,810) (13,350) (671,816) Amounts reclassified from accumulated other comprehensive income (loss) 4,960 2,866 1,610 9,436 Other comprehensive (loss), net of tax (635,696) (14,944) (11,740) (662,380) Balance at December 31, 2022 (631,160) (8,874) (44,926) (684,960) Other comprehensive income before reclassifications 86,391 4,066 11,794 102,251 Amounts reclassified from accumulated other comprehensive 27,319 1,939 2,880 32,138 Other comprehensive income, net of tax 113,710 6,005 14,674 134,389 Balance at December 31, 2023 $ (517,450) $ (2,869) $ (30,252) $ (550,571)
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table further summarizes the amounts reclassified from accumulated other comprehensive (loss) income: Years ended December 31, Accumulated Other Comprehensive (Loss) Income Components 2023 2022 2021 Associated Line Item in the Consolidated Statement Of Income (In thousands) Investment securities available-for-sale: Net unrealized holding (losses) $ (37,356) $ (6,751) $ — (Loss) on sale of investment securities (1) Tax benefit 10,037 1,791 — Income tax expense Net of tax $ (27,319) $ (4,960) $ — Derivative instruments: Hedge terminations $ (310) $ (306) $ (306) Interest expense Premium amortization (2,349) (3,626) (4,109) Interest income Tax benefit 720 1,066 1,154 Income tax expense Net of tax $ (1,939) $ (2,866) $ (3,261) Defined benefit pension and other postretirement benefit plans: Actuarial net loss amortization $ (2,083) $ (2,210) $ (4,102) Other expense Other (1,869) — — Other expense Tax benefit 1,072 600 1,078 Income tax expense Net of tax $ (2,880) $ (1,610) $ (3,024) (1) Losses recognized on the sale of investment securities are generally included as a component of non-interest income, unless any portion or all of the loss is attributed to a decline in credit quality, in which the amount recognized is then included in the Provision for credit losses. During the years ended December 31, 2023, and 2022, $3.8 million and zero of the total loss recognized on the sale of investment securities was included in the Provision for credit losses, respectively. The following tables summarize each component of other comprehensive income (loss) and the related tax effects: Year ended December 31, 2023 (In thousands) Amount Tax Benefit (Expense) Amount Investment securities available-for-sale: Net unrealized holding gains arising during the year $ 118,410 $ (32,019) $ 86,391 Reclassification adjustment for net realized losses included in net income 37,356 (10,037) 27,319 Total investment securities available-for-sale 155,766 (42,056) 113,710 Derivative instruments: Net unrealized gains arising during the year 5,578 (1,512) 4,066 Reclassification adjustment for net realized losses included in net income 2,659 (720) 1,939 Total derivative instruments 8,237 (2,232) 6,005 Defined benefit pension and other postretirement benefit plans: Net actuarial gain arising during the year 16,183 (4,389) 11,794 Reclassification adjustment for actuarial net loss amortization and other 3,952 (1,072) 2,880 Total defined benefit pension and postretirement benefit plans 20,135 (5,461) 14,674 Other comprehensive income, net of tax $ 184,138 $ (49,749) $ 134,389 Year ended December 31, 2022 (In thousands) Amount Tax Benefit (Expense) Amount Investment securities available-for-sale: Net unrealized holding (losses) arising during the year $ (878,366) $ 237,710 $ (640,656) Reclassification adjustment for net realized losses included in net income 6,751 (1,791) 4,960 Total investment securities available-for-sale (871,615) 235,919 (635,696) Derivative instruments: Net unrealized (losses) arising during the year (24,440) 6,630 (17,810) Reclassification adjustment for net realized losses included in net income 3,932 (1,066) 2,866 Total derivative instruments (20,508) 5,564 (14,944) Defined benefit pension and other postretirement benefit plans: Net actuarial (loss) arising during the year (18,319) 4,969 (13,350) Reclassification adjustment for net actuarial loss amortization included in net income 2,210 (600) 1,610 Total defined benefit pension and postretirement benefit plans (16,109) 4,369 (11,740) Other comprehensive (loss), net of tax $ (908,232) $ 245,852 $ (662,380) Year ended December 31, 2021 (In thousands) Amount Tax Benefit (Expense) Amount Investment securities available-for-sale: Net unrealized holding (losses) arising during the year $ (85,368) $ 22,480 $ (62,888) Total investment securities available-for-sale (85,368) 22,480 (62,888) Derivative instruments: Net unrealized (losses) arising during the year (23,216) 6,107 (17,109) Reclassification adjustment for net realized losses included in net income 4,415 (1,154) 3,261 Total derivative instruments (18,801) 4,953 (13,848) Defined benefit pension and other postretirement benefit plans: Net actuarial gain arising during the year 12,052 (3,176) 8,876 Reclassification adjustment for net actuarial loss amortization included in net income 4,102 (1,078) 3,024 Total defined benefit pension and postretirement benefit plans 16,154 (4,254) 11,900 Other comprehensive (loss), net of tax $ (88,015) $ 23,179 $ (64,836)

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2023
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Information On The Capital Ratios	The following table provides information on the regulatory capital ratios for the Holding Company and the Bank: At December 31, 2023 Actual (1) Minimum Requirement Well Capitalized (In thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 Risk-Based Capital $ 6,188,433 11.11 % $ 2,507,190 4.5 % $ 3,621,497 6.5 % Tier 1 Risk-Based Capital 6,472,412 11.62 3,342,920 6.0 4,457,227 8.0 Total Risk-Based Capital 7,643,423 13.72 4,457,227 8.0 5,571,534 10.0 Tier 1 Leverage Capital 6,472,412 9.06 2,857,890 4.0 3,572,362 5.0 Webster Bank CET1 Risk-Based Capital $ 6,913,443 12.43 % $ 2,502,835 4.5 % $ 3,615,206 6.5 % Tier 1 Risk-Based Capital 6,913,443 12.43 3,337,113 6.0 4,449,484 8.0 Total Risk-Based Capital 7,494,332 13.47 4,449,484 8.0 5,561,855 10.0 Tier 1 Leverage Capital 6,913,443 9.69 2,855,212 4.0 3,569,015 5.0 At December 31, 2022 Actual (1) Minimum Requirement Well Capitalized (In thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 Risk-Based Capital $ 5,822,369 10.71 % $ 2,446,344 4.5 % $ 3,533,608 6.5 % Tier 1 Risk-Based Capital 6,106,348 11.23 3,261,792 6.0 4,349,056 8.0 Total Risk-Based Capital 7,203,029 13.25 4,349,056 8.0 5,436,320 10.0 Tier 1 Leverage Capital 6,106,348 8.95 2,730,212 4.0 3,412,765 5.0 Webster Bank CET1 Risk-Based Capital $ 6,661,504 12.28 % $ 2,442,058 4.5 % $ 3,527,417 6.5 % Tier 1 Risk-Based Capital 6,661,504 12.28 3,256,078 6.0 4,341,437 8.0 Total Risk-Based Capital 7,165,935 13.20 4,341,437 8.0 5,426,796 10.0 Tier 1 Leverage Capital 6,661,504 9.77 2,727,476 4.0 3,409,345 5.0 (1) In accordance with regulatory capital rules, the Company elected an option to delay the estimated impact of the adoption of CECL on its regulatory capital over a two-year deferral period, which ended on January 1, 2022, and a subsequent three-year transition period ending on December 31, 2024. During the three-year transition period, regulatory capital ratios will phase out the aggregate amount of the regulatory capital benefit provided from the delayed CECL adoption in the initial two years. For 2022, 2023, and 2024, the Company is allowed 75%, 50%, and 25%, respectively, of the regulatory capital benefit as of December 31, 2021, with full absorption occurring in 2025.

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Earnings Per Share Basic And Diluted	The following table summarizes the calculation of basic and diluted earnings per common share: Years ended December 31, (In thousands, except per share data) 2023 2022 2021 Net income $ 867,840 $ 644,283 $ 408,864 Less: Preferred stock dividends 16,650 15,919 7,875 Net income available to common stockholders 851,190 628,364 400,989 Less: Earnings allocated to participating securities 7,922 5,672 2,302 Earnings applicable to common stockholders $ 843,268 $ 622,692 $ 398,687 Weighted-average common shares outstanding - basic 171,775 167,452 89,983 Add: Effect of dilutive stock options and restricted stock 108 95 223 Weighted-average common shares outstanding - diluted 171,883 167,547 90,206 Basic earnings per common share $ 4.91 $ 3.72 $ 4.43 Diluted earnings per common share 4.91 3.72 4.42

Derivative Financial Instrument

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]	The following table presents the notional amounts and fair values, including accrued interest, of derivative positions: At December 31, 2023 Asset Derivatives Liability Derivatives (In thousands) Notional Amounts Fair Value Notional Amounts Fair Value Designated as hedging instruments: Interest rate derivatives (1) $ 2,750,000 $ 11,140 $ 2,700,000 $ 13,679 Not designated as hedging instruments: Interest rate derivatives (1) 8,284,356 319,122 8,272,197 321,064 Mortgage banking derivatives (2) 2,798 37 — — Other (3) 340,553 337 731,055 1,067 Total not designated as hedging instruments 8,627,707 319,496 9,003,252 322,131 Gross derivative instruments, before netting $ 11,377,707 330,636 $ 11,703,252 335,810 Less: Master netting agreements 55,949 55,949 Cash collateral received/paid 232,190 — Total derivative instruments, after netting $ 42,497 $ 279,861 At December 31, 2022 Asset Derivatives Liability Derivatives (In thousands) Notional Amounts Fair Value Notional Amounts Fair Value Designated as hedging instruments: Interest rate derivatives (1) $ 1,350,000 $ 1,515 $ 1,750,000 $ 9,632 Not designated as hedging instruments: Interest rate derivatives (1) 7,024,507 221,225 7,022,844 403,952 Mortgage banking derivatives (2) 3,283 32 — — Other (3) 161,934 134 606,478 915 Total not designated as hedging instruments 7,189,724 221,391 7,629,322 404,867 Gross derivative instruments, before netting $ 8,539,724 222,906 $ 9,379,322 414,499 Less: Master netting agreements 16,129 16,129 Cash collateral received/paid 184,095 — Total derivative instruments, after netting $ 22,682 $ 398,370 (1) Balances related to clearing houses are presented as a single unit of account. In accordance with their rule books, clearing houses legally characterize variation margin payments as settlement of derivatives rather than collateral against derivative positions. Notional amounts of interest rate swaps cleared through clearing houses included $0.1 billion and $2.7 billion for asset derivatives at December 31, 2023, and 2022, respectively. The related fair values approximate zero. For liability derivatives, there were no interest rate swaps cleared through clearing houses at both December 31, 2023, and 2022. (2) Notional amounts related to residential loans exclude approved floating rate commitments of $1.0 million and $2.4 million at December 31, 2023, and 2022, respectively. (3) Other derivatives include foreign currency forward contracts related to lending arrangements, a Visa equity swap transaction, and risk participation agreements. Notional amounts of risk participation agreements include $299.2 million and $125.6 million for asset derivatives and $682.9 million and $559.2 million for liability derivatives at December 31, 2023, and 2022, respectively, which have insignificant related fair values.
Schedule of Net Investment Hedges, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The following tables represent the off-setting of derivative financial instruments that are subject to master netting agreements: At December 31, 2023 (In thousands) Gross Amount Recognized Derivative Offset Amount Cash Collateral Net Amount Presented Asset derivatives $ 289,778 $ 55,949 $ 232,190 $ 1,639 Liability derivatives 55,949 55,949 — — At December 31, 2022 (In thousands) Gross Amount Recognized Derivative Offset Amount Cash Collateral Received/Paid Net Amount Presented Asset derivatives $ 217,246 $ 16,129 $ 184,095 $ 17,022 Liability derivatives 16,129 16,129 — —
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The following table summarizes the income statement effect of derivatives designated as hedging instruments: Recognized In Years ended December 31, (In thousands) Net Interest Income 2023 2022 2021 Fair value hedges: Interest rate derivatives Deposits interest expense $ 3,194 $ — $ — Hedged item Deposits interest expense (15) — — Net recognized on fair value hedges $ (3,179) $ — $ — Cash flow hedges: Interest rate derivatives Long-term debt interest expense $ 310 $ 306 $ 411 Interest rate derivatives Interest and fees on loans and leases (14,628) 1,935 10,676 Net recognized on cash flow hedges $ (14,938) $ 1,629 $ 10,265 The following table summarizes information related to fair value hedging adjustments: Consolidated Balance Sheet Line Item in Which Previously Hedged Item is Located Notional Amount of Previously Hedged Item Carrying Amount of Previously Cumulative Amount of Fair Value Hedging Adjustment Included in Carrying Amount (1) At December 31, At December 31, At December 31, (In thousands) 2023 2022 2023 2022 2023 2022 Deposits $ 400,000 $ — $ 401,320 $ — $ 1,320 $ — Long-term debt 300,000 300,000 328,104 333,458 28,104 33,458
Other Derivatives Not Designated For Hedge Accounting	The following table summarizes the income statement effect of derivatives not designated as hedging instruments: Recognized In Years ended December 31, (In thousands) Non-interest Income 2023 2022 2021 Interest rate derivatives Other income $ (6,159) $ 25,092 $ 10,369 Mortgage banking derivatives Mortgage banking activities 5 (48) (776) Other Other income (2,476) 3,249 878 Total not designated as hedging instruments $ (8,630) $ 28,293 $ 10,471

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Option, Disclosures [Table Text Block]	The following table compares the fair value to the unpaid principal balance of originated loans held for sale: At December 31, 2023 2022 (In thousands) Fair Value Unpaid Principal Balance Difference Fair Value Unpaid Principal Balance Difference Originated loans held for sale $ 2,610 $ 2,658 $ (48) $ 1,991 $ 1,631 $ 360
Fair Value Measurement Inputs and Valuation Techniques	The following table summarizes the unobservable inputs used to derive the estimated fair value of the Company’s contingent consideration liabilities at December 31, 2023 (dollars in thousands): Agreement Maximum Amount Probability of Achievement Payment Term Discount Rate Fair Value (i) Re-sign broker dealers $ 4,826 99.0 % 1.88 6.40 % $ 4,232 (ii) Deposit program growth $ 12,500 100.0 % 1.00 6.40 % $ 11,568
Fair Value Of Assets And Liabilities Measured On Recurring Basis	The following table summarizes the fair values of assets and liabilities measured at fair value on a recurring basis: At December 31, 2023 (In thousands) Level 1 Level 2 Level 3 Total Financial Assets: Available-for-sale securities: Government agency debentures $ — $ 264,633 $ — $ 264,633 Municipal bonds and notes — 1,573,233 — 1,573,233 Agency CMO — 48,941 — 48,941 Agency MBS — 3,347,098 — 3,347,098 Agency CMBS — 2,288,071 — 2,288,071 CMBS — 763,749 — 763,749 Corporate debt — 622,155 — 622,155 Private label MBS — 42,808 — 42,808 Other — 9,041 — 9,041 Total available-for-sale securities — 8,959,729 — 8,959,729 Gross derivative instruments, before netting (1) 217 330,419 — 330,636 Originated loans held for sale — 2,610 — 2,610 Investments held in Rabbi Trusts 11,900 — — 11,900 Alternative investments 959 — — 959 Alternative investments measured at NAV (2) — — — 35,888 Total financial assets $ 13,076 $ 9,292,758 $ — $ 9,341,722 Financial Liabilities: Gross derivative instruments, before netting (1) $ 970 $ 334,840 $ — $ 335,810 Contingent consideration — — 15,800 15,800 Total financial liabilities $ 970 $ 334,840 $ 15,800 $ 351,610 At December 31, 2022 (In thousands) Level 1 Level 2 Level 3 Total Financial Assets: Available-for-sale investment securities: U.S. Treasury notes $ 717,040 $ — $ — $ 717,040 Government agency debentures — 258,374 — 258,374 Municipal bonds and notes — 1,633,202 — 1,633,202 Agency CMO — 59,965 — 59,965 Agency MBS — 2,158,024 — 2,158,024 Agency CMBS — 1,406,486 — 1,406,486 CMBS — 896,640 — 896,640 CLO — 2,107 — 2,107 Corporate debt — 704,412 — 704,412 Private label MBS — 44,249 — 44,249 Other — 12,198 — 12,198 Total available-for-sale securities 717,040 7,175,657 — 7,892,697 Gross derivative instruments, before netting (1) 79 222,827 — 222,906 Originated loans held for sale — 1,991 — 1,991 Investments held in Rabbi Trust 12,103 — — 12,103 Alternative investments 430 — — 430 Alternative investments measured at NAV (2) — — — 89,248 Total financial assets $ 729,652 $ 7,400,475 $ — $ 8,219,375 Financial Liabilities: Gross derivative instruments, before netting (1) $ 843 $ 413,656 $ — $ 414,499 (1) Additional information regarding the impact of netting derivative assets and derivative liabilities, as well as the impact from offsetting cash collateral paid to the same derivative counterparties, can be found within Note 17: Derivative Financial Instruments. (2) Certain alternative investments are recorded at NAV. Assets measured at NAV are not classified within the fair value hierarchy.
Summary Of Estimated Fair Values Of Significant Financial Instruments	The following table summarizes the carrying amounts, estimated fair values, and classifications within the fair value hierarchy of selected financial instruments and mortgage servicing rights: At December 31, 2023 2022 (In thousands) Carrying Fair Carrying Fair Assets: Level 1 Cash and cash equivalents $ 1,715,795 $ 1,715,795 $ 839,943 $ 839,943 Level 2 Held-to-maturity investment securities 7,074,588 6,264,623 6,564,697 5,761,453 Level 3 Loans and leases, net 50,090,315 48,048,106 49,169,685 47,604,463 Mortgage servicing rights 8,523 24,495 9,515 27,043 Liabilities: Level 2 Deposit liabilities $ 52,319,825 $ 52,319,825 $ 49,893,391 $ 49,893,391 Time deposits 8,464,459 8,426,708 4,160,949 4,091,979 Securities sold under agreements to repurchase and other borrowings 458,387 458,380 1,151,830 1,151,797 FHLB advances 2,360,018 2,358,381 5,460,552 5,459,218 Long-term debt (1) 1,048,820 999,918 1,073,128 1,001,779 (1)

Retirement Benefit Plans (Table

Retirement Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Schedule of Defined Benefit Plans Disclosures	The following table summarizes the changes in the benefit obligation, fair value of plan assets, and funded status of the defined benefit pension and postretirement benefit plans at December 31: Pension SERP OPEB (In thousands) 2023 2022 2023 2022 2023 2022 Change in benefit obligation: Beginning balance $ 187,836 $ 250,263 $ 4,245 $ 1,873 $ 22,822 $ 1,904 Benefit obligation assumed from Sterling — — — 4,517 — 26,030 Service cost — — — — 27 34 Interest cost 8,782 5,565 191 107 1,042 652 Actuarial (gain) loss 3,333 (57,751) 183 (581) (382) (4,992) Benefits paid (9,965) (10,241) (480) (1,671) (840) (806) Ending balance 189,986 187,836 4,139 4,245 22,669 22,822 Change in plan assets: Beginning balance 201,382 271,846 — — — — Actual return on plan assets 25,750 (60,223) — — — — Employer contributions — — 480 1,671 840 806 Benefits paid (9,965) (10,241) (480) (1,671) (840) (806) Ending balance 217,167 201,382 — — — — Funded status (1) $ 27,181 $ 13,546 $ (4,139) $ (4,245) $ (22,669) $ (22,822) (1) The overfunded (underfunded) status of each plan is respectively included in Accrued interest receivable and other assets or Accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets, as applicable. The following table sets forth by level within the fair value hierarchy the Pension Plan's assets at fair value: At December 31, 2023 2022 (In thousands) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Common collective trusts $ — $ 195,004 $ — $ 195,004 $ — $ 172,941 $ — $ 172,941 Registered investment companies 20,965 — — 20,965 26,923 — — 26,923 Cash and cash equivalents 1,198 — — 1,198 1,518 — — 1,518 Total pension plan assets $ 22,163 $ 195,004 $ — $ 217,167 $ 28,441 $ 172,941 $ — $ 201,382
Schedule of Assumptions Used	The following table summarizes the weighted-average assumptions used to determine the benefit obligation at December 31: Discount Rate 2023 2022 Pension: Webster Bank Pension Plan 4.76 % 4.96 % SERP: Webster Bank Supplemental Defined Benefit Plan for Executive Officers 4.68 % 4.88 % Astoria Bank Excess Benefit and Supplemental Benefit Plans 4.56 4.77 Astoria Bank Directors' Retirement Plan 4.50 4.70 Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors 4.50 4.70 Supplemental Executive Retirement Plan of Provident Bank 4.83 5.04 Supplemental Executive Retirement Plan of Provident Bank - Other 4.71 4.90 OPEB: Webster Bank Postretirement Medical Benefit Plan 4.54 % 4.72 % Sterling Bancorp Supplemental Postretirement Life Insurance Plan 4.51 4.70 Astoria Bank Postretirement Welfare Benefit Plans 4.74 4.94 Split Dollar Life Insurance Arrangement 4.45 4.63 The following table summarizes the weighted-average assumptions used to determine net periodic benefit cost (income) for the years ended December 31: Discount Rate 2023 2022 2021 Pension: Webster Bank Pension Plan 4.96 % 2.65 % 2.29 % SERP: Webster Bank Supplemental Defined Benefit Plan for Executive Officers 4.88 % 2.45 % 1.91 % Astoria Bank Excess Benefit and Supplemental Benefit Plans 4.77 2.58 n/a Astoria Bank Directors' Retirement Plan 4.70 2.23 n/a Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors 4.70 2.37 n/a Supplemental Executive Retirement Plan of Provident Bank 5.04 2.76 n/a Supplemental Executive Retirement Plan of Provident Bank - Other 4.90 2.38 n/a OPEB: Webster Bank Postretirement Medical Benefit Plan 4.72 % 1.99 % 1.40 % Sterling Bancorp Supplemental Postretirement Life Insurance Plan 4.70 2.35 n/a Astoria Bank Postretirement Welfare Benefit Plans 4.94 2.93 n/a Split Dollar Life Insurance Arrangement 4.63 2.20 n/a Expected Long-Term Rate of Return on Plan Assets 2023 2022 2021 Pension: Webster Bank Pension Plan 6.00 % 5.50 % 5.50 % Assumed Health Care Cost Trend Rate (1) 2023 2022 2021 OPEB: Webster Bank Postretirement Medical Benefit Plan 6.50 % 6.25 % 6.50 % Astoria Bank Postretirement Welfare Benefit Plans 6.40 6.60 n/a (1) The rates to which the healthcare cost trend rates are assumed to decline (ultimate trend rates) along with the year that the ultimate trend rates will be reached for the Webster Bank Postretirement Medical Benefit Plan and the Astoria Bank Postretirement Welfare Benefit Plans are 4.40% in 2032, and 4.50% in 2033, respectively.
Schedule of Net Periodic Benefit Cost Not yet Recognized	The following table summarizes the amounts recorded in accumulated other comprehensive (loss) income that have not yet been recognized in net periodic benefit cost (income) at December 31: Pension SERP OPEB (In thousands) 2023 2022 2023 2022 2023 2022 Net actuarial loss (gain) $ 41,296 $ 56,717 $ 312 $ 50 $ (3,231) $ (5,573) Deferred tax (benefit) expense (11,201) (15,383) (85) (14) 876 1,512 Net amount recorded in (AOCL) $ 30,095 $ 41,334 $ 227 $ 36 $ (2,355) $ (4,061)
Summary of Net Periodic Benefit Cost	The following table summarizes the components of net periodic benefit cost (income) for the years ended December 31: Pension SERP OPEB (In thousands) 2023 2022 2021 2023 2022 2021 2023 2022 2021 Service cost $ — $ — $ — $ — $ — $ — $ 27 $ 34 $ — Interest cost 8,782 5,565 4,663 191 107 30 1,042 652 19 Expected return on plan assets (11,778) (14,675) (14,385) — — — — — — Amortization of actuarial loss (gain) 4,781 2,224 4,102 6 26 38 (2,704) (40) (38) Net periodic benefit cost (income) (1) $ 1,785 $ (6,886) $ (5,620) $ 197 $ 133 $ 68 $ (1,635) $ 646 $ (19) (1) Net periodic benefit cost (income) is included in Other expense on the accompanying Consolidated Statements of Income.
Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss)	The following table summarizes amounts recognized in other comprehensive (loss) income, including reclassification adjustments, for the years ended December 31: Pension SERP OPEB (In thousands) 2023 2022 2021 2023 2022 2021 2023 2022 2021 Net actuarial (gain) loss $ (10,639) $ 17,148 $ (12,008) $ 183 $ (581) $ (77) $ (382) $ (4,992) $ 33 Amounts reclassified from (4,781) (2,224) (4,102) (6) (26) (38) 2,704 40 38 Total (gain) loss recognized in $ (15,420) $ 14,924 $ (16,110) $ 177 $ (607) $ (115) $ 2,322 $ (4,952) $ 71
Schedule of Expected Benefit Payments	At December 31, 2023, the expected future benefit payments for the Company's defined benefit pension and postretirement benefits plans are as follows: (In thousands) Pension SERP OPEB 2024 $ 10,634 $ 489 $ 2,926 2025 11,038 473 2,789 2026 11,429 455 2,552 2027 11,864 433 2,339 2028 12,246 409 2,083 Thereafter 64,148 1,646 7,393
Schedule of Multiemployer Plans	The following table summarizes information related to the Bank's participation in the multi-employer plan: (In thousands) Contributions Funded Status Plan Name Employer Identification Number Plan Number Surcharge Imposed 2023 2022 2021 2023 2022 Pentegra Defined Benefit Plan 13-5645888 333 No $448 $448 $692 At least 80 percent At least 80 percent

Share-Based Plans (Tables)

Share-Based Plans (Tables)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Summary of Restricted Stock and Stock Option Activity	The following table summarizes stock-based compensation plan activity for the year ended December 31, 2023: Non-Vested Restricted Stock Awards Outstanding Stock Options Outstanding Time-Based Performance-Based Number of Weighted-Average Number of Weighted-Average Number of Weighted-Average Balance, beginning of period 1,479,742 $ 50.47 310,374 $ 57.65 88,229 $ 23.76 Granted 937,735 51.35 286,161 48.86 — — Vested (740,748) 48.88 (60,988) 60.24 — — Forfeited (77,310) 51.62 (15,544) 55.54 — — Exercised — — — — (77,257) 23.00 Balance, end of period 1,599,419 52.72 520,003 52.58 10,972 29.14

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Operating Results And Total Assets Reportable Segments	The following table presents balance sheet information, including the appropriate allocations, for the Company's reportable segments and the Corporate and Reconciling category: At December 31, 2023 (In thousands) Commercial HSA Consumer Corporate and Consolidated Goodwill $ 2,029,204 $ 57,485 $ 544,776 $ — $ 2,631,465 Total assets 43,381,361 122,421 10,789,339 20,652,128 74,945,249 At December 31, 2022 (In thousands) Commercial HSA Consumer Corporate and Consolidated Goodwill $ 1,904,291 $ 57,779 $ 552,034 $ — $ 2,514,104 Total assets 44,380,582 122,729 10,625,334 16,148,876 71,277,521 The following tables present operating results, including the appropriate allocations, for the Company’s reportable segments and the Corporate and Reconciling category: Year ended December 31, 2023 (In thousands) Commercial HSA Consumer Corporate and Consolidated Net interest income $ 1,537,031 $ 302,856 $ 798,483 $ (301,101) $ 2,337,269 Non-interest income 132,660 88,113 107,456 (13,892) 314,337 Non-interest expense 439,290 168,160 425,281 383,624 1,416,355 Pre-tax, pre-provision net revenue 1,230,401 222,809 480,658 (698,617) 1,235,251 Provision for credit losses 131,237 — 11,972 7,538 150,747 Income before income taxes 1,099,164 222,809 468,686 (706,155) 1,084,504 Income tax expense 246,212 58,822 118,108 (206,478) 216,664 Net income $ 852,952 $ 163,987 $ 350,578 $ (499,677) $ 867,840 Year ended December 31, 2022 (In thousands) Commercial HSA Consumer Corporate and Consolidated Net interest income $ 1,346,384 $ 218,149 $ 720,789 $ (251,036) $ 2,034,286 Non-interest income 171,437 104,586 119,691 45,069 440,783 Non-interest expense 398,100 151,329 426,133 420,911 1,396,473 Pre-tax, pre-provision net revenue 1,119,721 171,406 414,347 (626,878) 1,078,596 Provision (benefit) for credit losses 276,550 — (3,754) 7,823 280,619 Income before income taxes 843,171 171,406 418,101 (634,701) 797,977 Income tax expense 207,188 45,937 108,657 (208,088) 153,694 Net income $ 635,983 $ 125,469 $ 309,444 $ (426,613) $ 644,283 Year ended December 31, 2021 (In thousands) Commercial HSA Consumer Corporate and Consolidated Net interest income $ 585,297 $ 168,595 $ 375,318 $ (228,121) $ 901,089 Non-interest income 83,538 102,814 95,887 41,133 323,372 Non-interest expense 192,977 134,258 297,217 120,648 745,100 Pre-tax, pre-provision net revenue 475,858 137,151 173,988 (307,636) 479,361 (Benefit) for credit losses (51,348) — (3,068) (84) (54,500) Income before income taxes 527,206 137,151 177,056 (307,552) 533,861 Income tax expense 134,965 36,619 42,139 (88,726) 124,997 Net income $ 392,241 $ 100,532 $ 134,917 $ (218,826) $ 408,864

Revenue from contracts with C_2

Revenue from contracts with Customers Revenue from Contracts with Customers Revenue from contracts with customers (Tables)	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenue from External Customers by Products and Services [Table Text Block]	Year ended December 31, 2023 (In thousands) Commercial HSA Consumer Corporate and Consolidated Non-interest Income: Deposit service fees $ 20,527 $ 81,051 $ 66,999 $ 741 $ 169,318 Loan and lease related fees (1) 17,633 — — — 17,633 Wealth and investment services (2) 11,543 — 17,478 (22) 28,999 Other — 7,062 6,199 4,193 17,454 Revenue from contracts with customers 49,703 88,113 90,676 4,912 233,404 Other sources of non-interest income 82,957 — 16,780 (18,804) 80,933 Total non-interest income $ 132,660 $ 88,113 $ 107,456 $ (13,892) $ 314,337 Year ended December 31, 2022 (In thousands) Commercial HSA Consumer Corporate and Consolidated Non-interest Income: Deposit service fees $ 27,663 $ 97,654 $ 71,353 $ 1,802 $ 198,472 Loan and lease related fees (1) 21,498 — — — 21,498 Wealth and investment services 11,350 — 28,957 (30) 40,277 Other — 6,932 1,493 — 8,425 Revenue from contracts with customers 60,511 104,586 101,803 1,772 268,672 Other sources of non-interest income 110,926 — 17,888 43,297 172,111 Total non-interest income $ 171,437 $ 104,586 $ 119,691 $ 45,069 $ 440,783 Year ended December 31, 2021 (In thousands) Commercial HSA Consumer Corporate and Consolidated Non-interest Income: Deposit service fees $ 16,933 $ 94,844 $ 50,561 $ 372 $ 162,710 Wealth and investment services 12,152 — 27,471 (37) 39,586 Other — 7,970 2,140 — 10,110 Revenue from contracts with customers 29,085 102,814 80,172 335 212,406 Other sources of non-interest income 54,453 — 15,715 40,798 110,966 Total non-interest income $ 83,538 $ 102,814 $ 95,887 $ 41,133 $ 323,372 (1) A portion of loan and lease related fees comprises income generated from factored receivables and payroll financing activities that is within the scope of ASC Topic 606. These Commercial Banking revenue streams were new to the Company in 2022 due to the businesses acquired in connection with the Sterling merger. (2) Effective as of the fourth quarter of 2022, the wealth and investment services revenue stream for Consumer Banking was impacted by the restructuring of a process in which the Company offers brokerage, investment advisory, and certain insurance-related services to customers. The staff providing these services, who had previously been employees of the Bank, are now employees of a third-party service provider. As a result, the Company now recognizes income from this program on a net basis, which thereby reduces gross reported wealth and investment services non-interest income and the related compensation and benefits non-interest expense on the accompanying Consolidated Statements of Income. Contracts with customers did not generate significant contract assets and liabilities at December 31, 2023, or 2022.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Credit Related Financial Instruments	The following table summarizes the outstanding amounts of credit-related financial instruments with off-balance sheet risk: At December 31, (In thousands) 2023 2022 Commitments to extend credit $ 12,026,597 $ 11,237,496 Standby letters of credit 482,462 380,655 Commercial letters of credit 54,382 53,512 Total credit-related financial instruments with off-balance sheet risk $ 12,563,441 $ 11,671,663

Parent Company Information (Tab

Parent Company Information (Tables)	12 Months Ended
	Dec. 31, 2023
Condensed Financial Information Disclosure [Abstract]
Schedule of Parent Company Information Balance Sheet	CONDENSED BALANCE SHEETS December 31, (In thousands) 2023 2022 Assets: Cash and due from banks $ 406,754 $ 305,331 Intercompany debt securities 150,000 150,000 Investment in subsidiaries 9,131,026 8,631,202 Alternative investments 59,015 46,349 Other assets 13,314 13,358 Total assets $ 9,760,109 $ 9,146,240 Liabilities and stockholders’ equity: Senior notes $ 458,698 $ 480,878 Subordinated notes 512,802 514,930 Junior subordinated debt 77,320 77,320 Accrued interest payable 12,693 7,457 Due to subsidiaries 477 3,858 Other liabilities 8,123 5,611 Total liabilities 1,070,113 1,090,054 Stockholders’ equity 8,689,996 8,056,186 Total liabilities and stockholders’ equity $ 9,760,109 $ 9,146,240
Schedule of Parent Company Information Income Statement	CONDENSED STATEMENTS OF INCOME Years ended December 31, (In thousands) 2023 2022 2021 Income: Dividend income from bank subsidiary $ 600,000 $ 475,000 $ 200,000 Interest income on securities and interest-bearing deposits 11,259 5,955 3,444 Alternative investments income 1,272 6,416 13,033 Other non-interest income 908 112 75 Total income 613,439 487,483 216,552 Expense: Interest expense on borrowings 37,933 34,284 16,876 Merger-related expenses 2,111 40,314 16,266 Other non-interest expense 31,600 22,592 15,921 Total expense 71,644 97,190 49,063 Income before income taxes and equity in undistributed earnings of subsidiaries 541,795 390,293 167,489 Income tax benefit 15,106 20,799 3,121 Equity in undistributed earnings of subsidiaries 310,939 233,191 238,254 Net income $ 867,840 $ 644,283 $ 408,864
Schedule of Parent Company Information Comprehensive Income Statement	CONDENSED STATEMENTS OF COMPREHENSIVE INCOME Years ended December 31, (In thousands) 2023 2022 2021 Net income $ 867,840 $ 644,283 $ 408,864 Other comprehensive income (loss), net of tax: Derivative instruments 229 226 226 Other comprehensive income (loss) of subsidiaries 134,160 (662,606) (65,062) Other comprehensive income (loss), net of tax 134,389 (662,380) (64,836) Comprehensive income (loss) $ 1,002,229 $ (18,097) $ 344,028
Schedule of Parent Company Information Cash Flow Statement	CONDENSED STATEMENTS OF CASH FLOWS Years ended December 31, (In thousands) 2023 2022 2021 Operating activities: Net income $ 867,840 $ 644,283 $ 408,864 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed earnings of subsidiaries (310,939) (233,191) (238,254) Common stock contribution to charitable foundation — 10,500 — Other, net (8,312) (2,853) 3,562 Net cash provided by operating activities 548,589 418,739 174,172 Investing activities: Alternative investments (capital call), net of distributions (13,070) (16,292) (6,304) Net cash received in business combination — 193,238 — Net cash (used in) provided by investing activities (13,070) 176,946 (6,304) Financing activities: Repayment of long-term debt (16,752) — — Dividends paid to common stockholders (278,155) (247,767) (145,223) Dividends paid to preferred stockholders (16,650) (13,725) (7,875) Exercise of stock options 1,723 703 3,492 Common stock repurchase program (107,984) (322,103) — Common shares acquired related to stock compensation plan activity (16,278) (23,655) (4,384) Net cash (used in) financing activities (434,096) (606,547) (153,990) Net increase (decrease) in cash and cash equivalents 101,423 (10,862) 13,878 Cash and cash equivalents, beginning of period 305,331 316,193 302,315 Cash and cash equivalents, at end of period $ 406,754 $ 305,331 $ 316,193

Summary of Significant Accoun_4

Summary of Significant Accounting Policies New Accounting Pronouncements - Narrative (Details) - USD ($) $ in Millions	Jan. 01, 2023	Dec. 31, 2023
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Threshold Period Past Due		90 days
Accounting Standards Update 2022-02 | Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	$ 5.9
Accounting Standards Update 2022-02 | Deferred Income Tax Assets, Net
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	1.6
Accounting Standards Update 2022-02 | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	$ 4.3
Building and Building Improvements | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		5 years
Building and Building Improvements | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		40 years
Leasehold Improvements | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		5 years
Leasehold Improvements | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		20 years
Furniture and Fixtures | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		5 years
Furniture and Fixtures | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		10 years
Information Technology and Data Processing | Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		3 years
Information Technology and Data Processing | Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, Plant and Equipment, Useful Life		7 years

Variable Interest Entities - Su

Variable Interest Entities - Summary of LIHTC Investments and Commitments (Details) - Variable Interest Entity, Not Primary Beneficiary [Member] - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Gross investment in LIHTC	$ 1,135,192	$ 797,453
Accumulated amortization	(141,199)	(69,424)
Net investment in LIHTC	993,993	728,029
Unfunded commitments for LIHTC investments	$ 549,258	$ 335,959

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Total liabilities	$ 66,255,253	$ 63,221,335
Commitments approved	0	313	$ 0
Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Assets	190,100	144,900
Commitments approved	334,900	211,800
Unfunded Loan Commitment [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable interest entities, total exposure of other investments including unfunded commitments	$ 307,200	$ 243,900

Mergers and Acquisitions - Narr

Mergers and Acquisitions - Narrative (Details) $ in Thousands						12 Months Ended
	Jan. 11, 2023 USD ($)	Nov. 07, 2022 USD ($)	Feb. 18, 2022 USD ($)	Jan. 31, 2022 USD ($) shares	Apr. 19, 2021	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Oct. 30, 2020 USD ($)	Dec. 16, 2019 USD ($)
Business Acquisition [Line Items]
Preferred stock, convertible | shares				1
Goodwill						$ 2,631,465	$ 2,514,104	$ 538,373
Provision (benefit) for credit losses						$ 150,747	$ 280,619	$ (54,500)
Series A Preferred Stock
Business Acquisition [Line Items]
Preferred stock, dividend rate (as a percent)				6.50%
Preferred Stock Series G Issued
Business Acquisition [Line Items]
Preferred stock, dividend rate (as a percent)						6.50%
Sterling
Business Acquisition [Line Items]
Share exchange ratio					0.4630
Goodwill				$ 1,914,204
Provision (benefit) for credit losses						$ 175,100
Aggregate principal amount				$ 3,266,096					$ 225,000	$ 274,000
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net						$ 25,600
Sterling | Core Deposits
Business Acquisition [Line Items]
Acquired intangible assets, useful life				10 years
Sterling | Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets, useful life				10 years
Bend Financial, Inc.
Business Acquisition [Line Items]
Equity interests acquired			100%
Cash consideration			$ 55,300
Aggregate principal amount			19,600
Bend Financial, Inc. | Internal use software
Business Acquisition [Line Items]
Intangible assets acquired			15,900
Bend Financial, Inc. | Customer Relationships
Business Acquisition [Line Items]
Intangible assets acquired			$ 3,000
Inland Bank and Trust HSA Portfolio Acquisition
Business Acquisition [Line Items]
Cash and deposits received from acquisition		$ 15,600
Deposit premium based on final settlement		2%
Core deposit intangible asset		$ 300
interLINK
Business Acquisition [Line Items]
Goodwill	$ 143,200
Equity interests acquired	100%
Cash consideration	$ 158,600
Business Combination, Consideration Transferred	174,600
Business Combination, Contingent Consideration, Liability	16,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Acquired Including Goodwill	31,400
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Royalty Liabilities	$ 15,900
interLINK | Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets, useful life	10 years
interLINK | Broker Dealer Relationship
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 36,000
interLINK | Developed Technology Rights
Business Acquisition [Line Items]
Intangible assets acquired	6,000
interLINK | Non Competition Agreement
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 4,000

Mergers and Acquisitions - Summ

Mergers and Acquisitions - Summary of Purchase Price Consideration (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Increase in stock compensation expense		$ 22,800	$ 18,800
Sterling
Business Acquisition [Line Items]
Webster common stock issued (in shares)	87,965,239
Price per share of Webster common stock on January 31, 2022 (in dollars per share)	$ 56.81
Total consideration	$ 5,180,300
Sterling | Common Stock
Business Acquisition [Line Items]
Total consideration	4,997,305
Sterling | Preferred Stock
Business Acquisition [Line Items]
Total consideration	138,942	$ 0	$ 138,942	$ 0
Sterling | Replacement Equity Awards
Business Acquisition [Line Items]
Total consideration	43,877
Sterling | Fractional Shares
Business Acquisition [Line Items]
Total consideration	$ 176

Mergers and Acquisitions - Su_2

Mergers and Acquisitions - Summary of Purchase Price Allocation (Details) - USD ($) $ in Thousands	Jan. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 30, 2020	Dec. 16, 2019
Liabilities:
Goodwill		$ 2,631,465	$ 2,514,104	$ 538,373
ROU lease assets		$ 183,441	$ 191,068
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net	Property and equipment, net	Property and equipment, net
Operating lease liabilities		$ 222,439	$ 239,281
Operating lease liabilities, location	Accrued expenses and other liabilities	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Sterling
Business Acquisition [Line Items]
Total consideration	$ 5,180,300
Assets:
Cash and due from banks	510,929
Interest-bearing deposits	3,207
Investment securities available-for-sale	4,429,948
Federal Home Loan Bank and Federal Reserve Bank Stock	150,502
Loans held for sale	23,517
Unpaid principal balance, total loans and leases		$ 20,816,348
Total loans and leases	20,498,706
Deferred tax assets, net	(59,716)
Premises and equipment	264,421
Other intangible assets	210,100
Bank-owned life insurance policies	645,510
Accrued interest receivable and other assets	986,729
Total assets acquired	27,663,853
Liabilities:
Non-interest-bearing deposits	6,620,248
Interest-bearing deposits	16,643,755
Securities sold under agreements to repurchase and other borrowings	27,184
Long-term debt	516,881
Accrued expenses and other liabilities	589,689
Total liabilities assumed	24,397,757
Net assets acquired	3,266,096				$ 225,000	$ 274,000
Goodwill	1,914,204
ROU lease assets	100,000
Operating lease liabilities	106,900
Sterling | Commercial non-mortgage
Assets:
Unpaid principal balance, total loans and leases		5,570,782
Total loans and leases	5,527,657
Sterling | Asset-based
Assets:
Unpaid principal balance, total loans and leases		694,137
Total loans and leases	683,958
Sterling | Commercial real estate
Assets:
Unpaid principal balance, total loans and leases		6,790,600
Total loans and leases	6,656,405
Sterling | Multi-family
Assets:
Unpaid principal balance, total loans and leases		4,303,381
Total loans and leases	4,255,906
Sterling | Equipment financing
Assets:
Unpaid principal balance, total loans and leases		1,350,579
Total loans and leases	1,314,311
Sterling | Warehouse lending
Assets:
Unpaid principal balance, total loans and leases		647,767
Total loans and leases	643,754
Sterling | Residential
Assets:
Unpaid principal balance, total loans and leases		1,313,785
Total loans and leases	1,281,637
Sterling | Home equity
Assets:
Unpaid principal balance, total loans and leases		132,758
Total loans and leases	122,553
Sterling | Other consumer
Assets:
Unpaid principal balance, total loans and leases		$ 12,559
Total loans and leases	$ 12,525

Mergers and Acquisitions - Sche

Mergers and Acquisitions - Schedule of PCD Loans and Leases by Portfolio Segment (Details) - Sterling $ in Thousands	Jan. 31, 2022 USD ($)
Business Acquisition [Line Items]
Unpaid principal balance	$ 3,936,434
ACL at acquisition	(136,316)
Non-credit (discount)	(43,731)
Fair value	3,756,387
Commercial
Business Acquisition [Line Items]
Unpaid principal balance	3,394,963
ACL at acquisition	(115,464)
Non-credit (discount)	(40,947)
Fair value	3,238,552
Consumer
Business Acquisition [Line Items]
Unpaid principal balance	541,471
ACL at acquisition	(20,852)
Non-credit (discount)	(2,784)
Fair value	$ 517,835

Mergers and Acquisitions - Su_3

Mergers and Acquisitions - Summary of Supplemental Pro Forma Information (Details) - Sterling - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Business Acquisition [Line Items]
Net interest income	$ 1,961,005	$ 1,802,862
Non-interest income	440,783	487,301
Net income	$ 869,639	$ 574,927

Mergers and Acquisitions- Summa

Mergers and Acquisitions- Summary of Supplemental Pro Forma Information Adjustments (Details) - Sterling - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Business Acquisition [Line Items]
Merger-related expenses		$ 246,461	$ 37,454
Compensation and benefits
Business Acquisition [Line Items]
Merger-related expenses		79,001	13,987
Occupancy
Business Acquisition [Line Items]
Merger-related expenses		36,586	256
Technology and equipment
Business Acquisition [Line Items]
Merger-related expenses		24,688	290
Business Combination, Increase (Decrease) In Acquisition Related Costs	$ 4,800
Professional and outside services
Business Acquisition [Line Items]
Merger-related expenses		416	0
Marketing
Business Acquisition [Line Items]
Merger-related expenses		73,070	22,273
Other expense
Business Acquisition [Line Items]
Merger-related expenses		$ 32,700	$ 648
Business Combination, Increase (Decrease) In Acquisition Related Costs	$ 1,700

Mergers and Acquisitions - Sc_2

Mergers and Acquisitions - Schedule of Restructuring Reserve by Type of Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Business Acquisition [Line Items]
Restructuring Reserve, Beginning Balance	$ 37,945	$ 10,835
Additions, charged to expense	32,069	70,244
Payments for Restructuring	(44,798)	(38,804)
Restructuring Reserve, Retention And Other Adjustment	(7,887)	(4,330)
Restructuring Reserve, Ending Balance	17,329	37,945
Employee Severance [Member]
Business Acquisition [Line Items]
Restructuring Reserve, Beginning Balance	7,583	10,835
Additions, charged to expense	18,069	36,092
Payments for Restructuring	(14,247)	(35,014)
Restructuring Reserve, Retention And Other Adjustment	(1,300)	(4,330)
Restructuring Reserve, Ending Balance	10,105	7,583
Employee Severance [Member] | Sterling
Business Acquisition [Line Items]
Restructuring Reserve, Retention And Other Adjustment		(4,100)
Contract Termination [Member]
Business Acquisition [Line Items]
Restructuring Reserve, Beginning Balance	30,362	0
Additions, charged to expense	14,000	34,152
Payments for Restructuring	(30,551)	(3,790)
Restructuring Reserve, Retention And Other Adjustment	(6,587)	0
Restructuring Reserve, Ending Balance	$ 7,224	$ 30,362

Investment Securities (Summary

Investment Securities (Summary Of Investment Securities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Amortized Cost	$ 7,074,797	$ 6,564,879
Unrealized Gains	22,167	2,770
Unrealized Losses	(832,341)	(806,196)
Fair Value	6,264,623	5,761,453
Debt Securities, Held-to-maturity, Allowance for Credit Loss	209	182	$ 214	$ 299
Debt Securities, Held-to-maturity, Current	7,074,588	6,564,697
Interest Receivable	270,400	226,300
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	50,673	31
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	759,366	864,489
Pledged Financial Instruments, Not Separately Reported, Debt Securities Held-to-Maturity	6,795,203	1,857,512
Pledged Financial Instruments, Not Separately Reported, Debt Securities Available-for-sale or Held-for-investment	8,213,545	3,768,173
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	9,668,422	8,757,155
Fair Value	8,959,729	7,892,697
Held-to-maturity Securities [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Interest Receivable	24,900	24,200
Available-for-sale Securities
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Interest Receivable	42,500	36,900
Agency CMO
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Amortized Cost	23,470	28,358
Unrealized Gains	0	0
Unrealized Losses	(1,728)	(2,060)
Fair Value	21,742	26,298
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Debt Securities, Held-to-maturity, Current	23,470	28,358
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	4,053	5,019
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	52,994	64,984
Fair Value	48,941	59,965
Agency MBS
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Amortized Cost	2,409,521	2,626,114
Unrealized Gains	1,141	827
Unrealized Losses	(284,776)	(339,592)
Fair Value	2,125,886	2,287,349
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Debt Securities, Held-to-maturity, Current	2,409,521	2,626,114
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	32,461	26
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	253,503	303,339
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	3,568,140	2,461,337
Fair Value	3,347,098	2,158,024
Agency commercial mortgage-backed securities (agency CMBS) [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Amortized Cost	3,625,627	2,831,949
Unrealized Gains	18,586	845
Unrealized Losses	(514,534)	(407,648)
Fair Value	3,129,679	2,425,146
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Debt Securities, Held-to-maturity, Current	3,625,627	2,831,949
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	18,204	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	299,571	258,114
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	2,569,438	1,664,600
Fair Value	2,288,071	1,406,486
CMBS
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Amortized Cost	100,075	149,613
Unrealized Gains	0	0
Unrealized Losses	(6,426)	(9,713)
Fair Value	93,649	139,900
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Debt Securities, Held-to-maturity, Current	100,075	149,613
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	24,729	32,948
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	788,478	929,588
Fair Value	763,749	896,640
CLO
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		1
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss		2,108
Fair Value		2,107
Corporate debt
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	82,414	91,587
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	704,569	795,999
Fair Value	622,155	704,412
Municipal Bonds [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Amortized Cost	916,104	928,845
Unrealized Gains	2,440	1,098
Unrealized Losses	(24,877)	(47,183)
Fair Value	893,667	882,760
Debt Securities, Held-to-maturity, Allowance for Credit Loss	209	182
Debt Securities, Held-to-maturity, Current	915,895	928,663
U.S. Treasury notes
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains		0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		38,928
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss		755,968
Fair Value		717,040
Government agency debentures
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	37,579	43,644
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	302,212	302,018
Fair Value	264,633	258,374
Municipal bonds and notes
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	8	5
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	52,901	85,913
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	1,626,126	1,719,110
Fair Value	1,573,233	1,633,202
Private label MBS
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	3,827	4,646
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	46,635	48,895
Fair Value	42,808	44,249
Other
Debt Securities, Available-for-sale [Abstract]
Unrealized Gains	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	789	350
Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss	9,830	12,548
Fair Value	$ 9,041	$ 12,198

Investment Securities (Summar_2

Investment Securities (Summary Of Gross Unrealized Losses Not Considered OTTI) (Detail) $ in Thousands	Dec. 31, 2023 USD ($) holding	Dec. 31, 2022 USD ($) holding
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 567,445	$ 5,417,865
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(17,416)	(532,120)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	6,499,763	2,429,126
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (741,950)	$ (332,369)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	1,181	1,282
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 7,067,208	$ 7,846,991
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(759,366)	(864,489)
Agency CMO
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		55,693
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(4,640)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	48,941	4,272
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (4,053)	$ (379)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	36	39
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 48,941	$ 59,965
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(4,053)	(5,019)
Agency MBS
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	71,187	1,641,544
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(272)	(206,412)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,945,221	515,206
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (253,231)	$ (96,927)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	457	460
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 2,016,408	$ 2,156,750
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(253,503)	(303,339)
Agency commercial mortgage-backed securities (agency CMBS) [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	430,070	485,333
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(16,137)	(68,674)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,314,681	921,153
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (283,434)	$ (189,440)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	145	132
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 1,744,751	$ 1,406,486
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(299,571)	(258,114)
CMBS
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	43,844	273,150
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(856)	(8,982)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	719,905	598,490
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (23,873)	$ (23,966)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	42	52
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 763,749	$ 871,640
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(24,729)	(32,948)
CLO
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer		2,107
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		$ (1)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding		1
Debt Securities, Available-for-sale, Unrealized Loss Position		$ 2,107
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss		(1)
Corporate debt
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	4,278	692,990
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(27)	(89,692)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	617,877	8,421
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (82,387)	$ (1,895)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	91	105
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 622,155	$ 701,411
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(82,414)	(91,587)
U.S. Treasury notes
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		337,563
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(19,167)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer		379,477
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		$ (19,761)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding		23
Debt Securities, Available-for-sale, Unrealized Loss Position		$ 717,040
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss		(38,928)
Government agency debentures
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		258,374
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		$ (43,644)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	264,633
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (37,579)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	19	19
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 264,633	$ 258,374
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(37,579)	(43,644)
Municipal bonds and notes
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	18,066	1,616,771
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(124)	$ (85,913)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	1,536,656
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (52,777)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	386	444
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 1,554,722	$ 1,616,771
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(52,901)	(85,913)
Private label MBS
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0	44,249
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	$ (4,646)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	42,808
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (3,827)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	3	3
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 42,808	$ 44,249
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(3,827)	(4,646)
Other
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		12,198
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		$ (350)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	9,041
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (789)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | holding	2	4
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 9,041	$ 12,198
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (789)	$ (350)

Investment Securities (Narrativ

Investment Securities (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Fair Value	$ 8,959,729,000	$ 7,892,697,000
Interest Receivable	270,400,000	226,300,000
Debt Maturity, Held-to-Maturity, Non-Accrual	0	0
Proceeds from sales of available-for-sale securities	789,603,000	172,947,000	$ 0
Equity Securities, FV-NI, Realized Loss	(37,400,000)	(6,800,000)
Total Loss Recognized, Portion Included In Provision For Credit Losses	3,800,000
Debt Securities, Available-for-Sale, Increase (Decrease) in Unrealized Losses	105,100,000
Callable [Member]
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Fair Value	3,000,000,000
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	900,000,000
Held-to-maturity Securities [Member]
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Interest Receivable	$ 24,900,000	$ 24,200,000

Investment Securities (Summar_3

Investment Securities (Summary Of Sale Proceeds Of Available For Sale Securities) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of available-for-sale securities	$ 789,603	$ 172,947	$ 0
Debt Securities, Available-for-sale, Realized Gain (Loss)	$ 33,620	$ 6,751	$ 0

Investment Securities (Summar_4

Investment Securities (Summary Of Debt Securities By Contractual Maturity) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	$ 37,908
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	644,959
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	1,363,257
Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost	7,622,298
Amortized Cost (1)	9,668,422	$ 8,757,155
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	36,958
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	616,176
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	1,263,900
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	7,042,695
Fair Value	8,959,729	7,892,697
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	8,122
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	59,932
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	363,498
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost	6,643,245
Investment securities held-to-maturity (fair value of $6,264,623 and $5,761,453)	7,074,797	6,564,879
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	8,136
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	60,434
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	349,083
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value	5,846,970
Debt Securities, Held-to-maturity, Fair Value	$ 6,264,623	$ 5,761,453

Investment Securities (Summar_5

Investment Securities (Summary of Debt Securities Held-to-Maturity) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	$ 7,074,797	$ 6,564,879
Interest Receivable	270,400	226,300
Agency CMO
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	23,470	28,358
Agency MBS
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	2,409,521	2,626,114
Agency commercial mortgage-backed securities (agency CMBS) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	3,625,627	2,831,949
Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	916,104	928,845
CMBS
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	100,075	149,613
Moody's, Aaa Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	433,554	485,648
Moody's, Aaa Rating [Member] | Agency CMO
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	0	0
Moody's, Aaa Rating [Member] | Agency MBS
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	0	0
Moody's, Aaa Rating [Member] | Agency commercial mortgage-backed securities (agency CMBS) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	0	0
Moody's, Aaa Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	333,479	336,035
Moody's, Aaa Rating [Member] | CMBS
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	100,075	149,613
Moody's, Aa1 Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	6,221,233	5,649,733
Moody's, Aa1 Rating [Member] | Agency CMO
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	23,470	28,358
Moody's, Aa1 Rating [Member] | Agency MBS
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	2,409,521	2,626,114
Moody's, Aa1 Rating [Member] | Agency commercial mortgage-backed securities (agency CMBS) [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	3,625,627	2,831,949
Moody's, Aa1 Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	162,615	163,312
Moody's, Aa1 Rating [Member] | CMBS
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	0	0
Moody's, Aa2 Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	253,671	255,235
Moody's, Aa2 Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	253,671	255,235
Moody's, Aa3 Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	115,404	116,870
Moody's, Aa3 Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	115,404	116,870
Moody's, A1 Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	32,732	38,177
Moody's, A1 Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	32,732	38,177
Moody's, A2 Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	0	4,165
Moody's, A2 Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	0	4,165
Moody's, Not Rated [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	14,038	15,051
Moody's, Not Rated [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	14,038	15,051
Moody's, A3 Rating [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	4,165	0
Moody's, A3 Rating [Member] | Municipal Bonds [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Held to maturity securities	$ 4,165	$ 0

Investment Securities (Debt and

Investment Securities (Debt and Equity Securities Allowance for Credit Losses) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Debt Securities, Held-to-maturity, Allowance for Credit Loss	$ 209	$ 182	$ 214	$ 299
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Recovery	27	(32)	$ (85)
Pledged Financial Instruments, Not Separately Reported, Debt Securities Available-for-sale or Held-for-investment	8,213,545	3,768,173
Pledged Financial Instruments, Not Separately Reported, Debt Securities Held-to-Maturity	6,795,203	1,857,512
Pledged For Municipal Deposits
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Pledged Financial Instruments, Not Separately Reported, Debt Securities Available-for-sale or Held-for-investment	2,102,115	2,573,072
Pledged Financial Instruments, Not Separately Reported, Debt Securities Held-to-Maturity	1,212,824	1,596,777
Pledged For Borrowings
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items]
Pledged Financial Instruments, Not Separately Reported, Debt Securities Available-for-sale or Held-for-investment	6,111,430	1,195,101
Pledged Financial Instruments, Not Separately Reported, Debt Securities Held-to-Maturity	$ 5,582,379	$ 260,735

Loans and Leases (Detail)

Loans and Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unamortized premiums	$ (33,800)	$ (68,700)
Interest Receivable	270,400	226,300
Total Loans and Leases	50,726,052	49,764,426
Total	$ 202,477	87,423	$ 21,977
% of Total Class	0.40%
Loans and leases	$ 50,726,052	49,764,426
Non-accrual	208,525	197,441
Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	50,470,541	49,493,591
Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	33,873	32,379
Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	12,835	40,289
Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	62
Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	145,646
CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	18,818
CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	425
Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8,120
CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	29,371
Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	202,477
Non-accrual	26,054
Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	176,423
Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Home equity | Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	651
Non-accrual	104
Home equity | Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	547
Home equity | Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Home equity | Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Home equity | Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial real estate | Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	20,882
Non-accrual	174
Commercial real estate | Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	20,708
Commercial real estate | Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial real estate | Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial real estate | Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Asset-based | Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	45,042
Non-accrual	0
Asset-based | Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	45,042
Asset-based | Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Asset-based | Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Asset-based | Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial non-mortgage | Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	133,135
Non-accrual	25,283
Commercial non-mortgage | Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	107,852
Commercial non-mortgage | Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial non-mortgage | Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial non-mortgage | Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Residential | Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	1,126
Non-accrual	136
Residential | Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	990
Residential | Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Residential | Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Residential | Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Equipment Financing | Aging Loan Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	1,641
Non-accrual	357
Equipment Financing | Aging Loan Modifications | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	1,284
Equipment Financing | Aging Loan Modifications | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Equipment Financing | Aging Loan Modifications | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Equipment Financing | Aging Loan Modifications | Financial Asset, Equal to or Greater than 90 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	0
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	40,929,834	40,103,951
Non-accrual	179,134	143,945
Commercial | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	40,734,291	39,907,180
Commercial | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	12,893	17,812
Commercial | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	3,238	34,301
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	13,569,762	12,997,163
Non-accrual	11,383	39,057
Commercial | Commercial real estate | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	13,556,736	12,933,052
Commercial | Commercial real estate | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,459	1,494
Commercial | Commercial real estate | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	0	23,492
Commercial | Commercial real estate | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0	183
Commercial | Commercial non-mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	16,885,475	16,392,795
Non-accrual	122,855	71,884
Commercial | Commercial non-mortgage | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	16,759,366	16,311,011
Commercial | Commercial non-mortgage | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	2,270	8,434
Commercial | Commercial non-mortgage | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	890	821
Commercial | Asset-based
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,557,841	1,821,642
Non-accrual	35,068	20,024
Commercial | Asset-based | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,522,773	1,795,697
Commercial | Asset-based | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	0	5,921
Commercial | Asset-based | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	0	0
Commercial | Multi-family
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	7,587,970	6,621,982
Non-accrual	0	636
Commercial | Multi-family | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	7,580,432	6,620,189
Commercial | Multi-family | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	5,198	1,157
Commercial | Multi-family | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	2,340	0
Commercial | Warehouse lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	0	641,976
Non-accrual		0
Commercial | Warehouse lending | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases		641,976
Commercial | Warehouse lending | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases		0
Commercial | Warehouse lending | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases		0
Commercial | Commercial non-mortgage | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		291	605
Commercial | Equipment Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,328,786	1,628,393
Non-accrual	9,828	12,344
Commercial | Equipment Financing | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,314,984	1,605,255
Commercial | Equipment Financing | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	3,966	806
Commercial | Equipment Financing | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	8	9,988
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	9,796,218	9,660,475
Non-accrual	29,391	53,496
Consumer | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	9,736,250	9,586,411
Consumer | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	20,980	14,567
Consumer | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	9,597	5,988
Consumer | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,516,955	1,633,107
Non-accrual	23,545	27,924
Consumer | Home equity | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	1,484,449	1,597,070
Consumer | Home equity | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	5,676	5,293
Consumer | Home equity | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	3,285	2,820
Consumer | Home equity | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		74	0
Consumer | Home equity | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		0	1,809
Consumer | 522291 Consumer Lending [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual	142	148
Consumer | Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	8,227,923	7,963,420
Non-accrual	5,704	25,424
Consumer | Residential | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	8,201,107	7,926,667
Consumer | Residential | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	14,894	8,246
Consumer | Residential | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	6,218	3,083
Consumer | Residential | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total		1,185	$ 99
Consumer | Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	51,340	63,948
Non-accrual	142	148
Consumer | Other consumer | Financial Asset, Not Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	50,694	62,674
Consumer | Other consumer | Financial Asset, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	410	1,028
Consumer | Other consumer | Financial Asset, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Loans and Leases	94	$ 85
Commercial non-mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 133,135
% of Total Class	0.80%
Commercial non-mortgage | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Commercial non-mortgage | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 96,895
Extended term by a weighted average	1 year 3 months 18 days
Commercial non-mortgage | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,062
Reduced weighted average interest rate	1.80%
Extended term by a weighted average	1 year 4 months 24 days
Commercial non-mortgage | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 425
Reduced weighted average interest rate	2%
Extended term by a weighted average	6 months
Payment deferrals weighted average	6 months
Commercial non-mortgage | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 5,858
Extended term by a weighted average	6 months
Commercial non-mortgage | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 28,860
Extended term by a weighted average	1 year 1 month 6 days
Payment deferrals weighted average	1 year
Asset-based
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 45,042
% of Total Class	2.90%
Asset-based | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Asset-based | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 45,042
Extended term by a weighted average	8 months 12 days
Asset-based | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Asset-based | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Asset-based | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Asset-based | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 20,882
% of Total Class	0.20%
Commercial real estate | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Commercial real estate | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 3,090
Extended term by a weighted average	2 years 2 months 12 days
Commercial real estate | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 17,107
Reduced weighted average interest rate	2.40%
Extended term by a weighted average	3 years
Commercial real estate | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Commercial real estate | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 174
Extended term by a weighted average	3 months 18 days
Commercial real estate | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 511
Extended term by a weighted average	6 months
Payment deferrals weighted average	6 months
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,126
% of Total Class	0%
Residential | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Residential | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 186
Extended term by a weighted average	2 years 9 months 18 days
Residential | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 136
Reduced weighted average interest rate	0.30%
Extended term by a weighted average	17 years 10 months 24 days
Residential | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Residential | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 804
Extended term by a weighted average	1 year
Residential | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Equipment financing | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extended term by a weighted average	6 months
Equipment Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,641
% of Total Class	0.10%
Equipment Financing | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Equipment Financing | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 357
Extended term by a weighted average	4 years 6 months
Equipment Financing | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Equipment Financing | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Equipment Financing | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,284
Equipment Financing | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0

Loans and Leases (Summary Of Lo

Loans and Leases (Summary Of Loan And Lease Portfolio Aging By Class Of Loan) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	$ 50,726,052	$ 49,764,426
90 or More Days Past Due and Accruing	278	726
Non-accrual	208,525	197,441
Total  Past Due and Non-accrual	39,037	42,059
Consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	9,796,218	9,660,475
90 or More Days Past Due and Accruing	0	13
Non-accrual	29,391	53,496
Total  Past Due and Non-accrual	13,376	25,640
Consumer | Home equity
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,516,955	1,633,107
90 or More Days Past Due and Accruing	0	0
Non-accrual	23,545	27,924
Total  Past Due and Non-accrual	12,471	15,193
Consumer | Other consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	51,340	63,948
90 or More Days Past Due and Accruing	0	13
Non-accrual	142	148
Consumer | Residential
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	8,227,923	7,963,420
90 or More Days Past Due and Accruing	0	0
Non-accrual	5,704	25,424
Total  Past Due and Non-accrual	856	10,442
Consumer | 522291 Consumer Lending [Member]
Financing Receivable, Past Due [Line Items]
Non-accrual	142	148
Total  Past Due and Non-accrual	49	5
Commercial
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	40,929,834	40,103,951
90 or More Days Past Due and Accruing	278	713
Non-accrual	179,134	143,945
Total  Past Due and Non-accrual	25,661	16,419
Commercial | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	13,569,762	12,997,163
90 or More Days Past Due and Accruing	184	68
Non-accrual	11,383	39,057
Total  Past Due and Non-accrual	2,681	90
Commercial | Commercial non-mortgage
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	16,885,475	16,392,795
90 or More Days Past Due and Accruing	94	645
Non-accrual	122,855	71,884
Total  Past Due and Non-accrual	20,066	12,598
Commercial | Asset-based
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,557,841	1,821,642
90 or More Days Past Due and Accruing	0	0
Non-accrual	35,068	20,024
Total  Past Due and Non-accrual	1,330	1,491
Commercial | Multi-family
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,587,970	6,621,982
90 or More Days Past Due and Accruing	0	0
Non-accrual	0	636
Total  Past Due and Non-accrual	0	0
Commercial | Warehouse lending
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	641,976
90 or More Days Past Due and Accruing		0
Non-accrual		0
Commercial | Equipment Financing
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,328,786	1,628,393
90 or More Days Past Due and Accruing	0	0
Non-accrual	9,828	12,344
Total  Past Due and Non-accrual	1,584	2,240
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	33,873	32,379
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	20,980	14,567
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer | Home equity
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	5,676	5,293
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer | Other consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	410	1,028
Financial Asset, 30 to 59 Days Past Due [Member] | Consumer | Residential
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	14,894	8,246
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	12,893	17,812
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,459	1,494
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial | Commercial non-mortgage
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	2,270	8,434
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial | Asset-based
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	5,921
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial | Multi-family
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	5,198	1,157
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial | Warehouse lending
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial | Equipment Financing
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	3,966	806
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	12,835	40,289
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	9,597	5,988
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer | Home equity
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	3,285	2,820
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer | Other consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	94	85
Financial Asset, 60 to 89 Days Past Due [Member] | Consumer | Residential
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	6,218	3,083
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	3,238	34,301
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	23,492
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial | Commercial non-mortgage
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	890	821
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial | Asset-based
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	0	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial | Multi-family
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	2,340	0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial | Warehouse lending
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial | Equipment Financing
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	8	9,988
Financial Asset, Not Past Due
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	50,470,541	49,493,591
Financial Asset, Not Past Due | Consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	9,736,250	9,586,411
Financial Asset, Not Past Due | Consumer | Home equity
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,484,449	1,597,070
Financial Asset, Not Past Due | Consumer | Other consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	50,694	62,674
Financial Asset, Not Past Due | Consumer | Residential
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	8,201,107	7,926,667
Financial Asset, Not Past Due | Commercial
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	40,734,291	39,907,180
Financial Asset, Not Past Due | Commercial | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	13,556,736	12,933,052
Financial Asset, Not Past Due | Commercial | Commercial non-mortgage
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	16,759,366	16,311,011
Financial Asset, Not Past Due | Commercial | Asset-based
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,522,773	1,795,697
Financial Asset, Not Past Due | Commercial | Multi-family
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,580,432	6,620,189
Financial Asset, Not Past Due | Commercial | Warehouse lending
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		641,976
Financial Asset, Not Past Due | Commercial | Equipment Financing
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	1,314,984	1,605,255
Financial Asset, Past Due
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	255,511	270,835
Financial Asset, Past Due | Consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	59,968	74,064
Financial Asset, Past Due | Consumer | Home equity
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	32,506	36,037
Financial Asset, Past Due | Consumer | Other consumer
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	646	1,274
Financial Asset, Past Due | Consumer | Residential
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	26,816	36,753
Financial Asset, Past Due | Commercial
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	195,543	196,771
Financial Asset, Past Due | Commercial | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	13,026	64,111
Financial Asset, Past Due | Commercial | Commercial non-mortgage
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	126,109	81,784
Financial Asset, Past Due | Commercial | Asset-based
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	35,068	25,945
Financial Asset, Past Due | Commercial | Multi-family
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	7,538	1,793
Financial Asset, Past Due | Commercial | Warehouse lending
Financing Receivable, Past Due [Line Items]
Total Loans and Leases		0
Financial Asset, Past Due | Commercial | Equipment Financing
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	13,802	$ 23,138
us-gaap_FinancialAssetNotPastDueMember | Commercial
Financing Receivable, Past Due [Line Items]
Total Loans and Leases	$ 28,500

Loans and Leases (Narrative) (D

Loans and Leases (Narrative) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan
Loans and Leases Receivable Disclosure [Abstract]
Interest on non-accrual loans that would have been recorded as additional interest income	$ 22.9	$ 16.9	$ 11
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans and Leases | loan		107	150
Unamortized premiums	$ (33.8)	$ (68.7)
Commercial non-mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans and Leases | loan	3
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 3.6
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans and Leases | loan	2
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 0.6
Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans and Leases | loan	2
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 0.3
Collateral Pledged [Member] | Asset Pledged as Collateral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 16,600
Commercial
Loans and Leases Receivable Disclosure [Abstract]
Write-down of TDR's		$ (14.7)	$ (3)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans and Leases | loan			0

Loans and Leases (Allowance For

Loans and Leases (Allowance For Loan And Lease Losses By Portfolio Segment) (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jan. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period		$ 594,741	$ 301,187	$ 359,431
Provision (benefit) charged to expense		143,209	272,797	(54,415)
Losses charged off		(117,212)	(87,522)	(18,654)
Recoveries		9,126	20,234	14,825
Specific reserves for TDR included in the balance of ALLL		635,737	594,741	301,187
Individually evaluated for impairment		48,194	47,234	21,073
Collectively evaluated for impairment		587,543	547,507	280,114
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0	88,045	0
Sterling | Financial Asset Acquired with Credit Deterioration
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 48,300
Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss		5,873		0	$ 0
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period		61,616	43,310	47,187
Provision (benefit) charged to expense		5,152	4,502	(5,764)
Losses charged off		(12,703)	(4,662)	(9,217)
Recoveries		5,840	8,797	11,104
Specific reserves for TDR included in the balance of ALLL		58,074	61,616	43,310
Individually evaluated for impairment		4,635	12,441	4,108
Collectively evaluated for impairment		53,439	49,175	39,202
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0	9,669	0
Consumer | Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss		(1,831)		0	0
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period		533,125	257,877	312,244
Provision (benefit) charged to expense		138,057	268,295	(48,651)
Losses charged off		(104,509)	(82,860)	(9,437)
Recoveries		3,286	11,437	3,721
Specific reserves for TDR included in the balance of ALLL		577,663	533,125	257,877
Individually evaluated for impairment		43,559	34,793	16,965
Collectively evaluated for impairment		534,104	498,332	240,912
Financing Receivable, Allowance for Credit Loss, Purchased with Credit Deterioration, Increase		0	$ 78,376	0
Commercial | Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Allowance for Credit Loss		$ 7,704		$ 0	$ 0

Loans and Leases (Summary Of Th

Loans and Leases (Summary Of The Recorded Investment Of Company's TDRs) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDR	$ 194,822
Specific reserves for TDR included in the balance of ALLL	594,741	$ 301,187	$ 635,737	$ 359,431
Additional funds committed to borrowers in TDR status	1,724
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDR included in the balance of ALLL	533,125	257,877	577,663	312,244
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	14,700	3,000
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDR included in the balance of ALLL	61,616	43,310	$ 58,074	$ 47,187
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	300	$ 400
Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDR	110,868
Nonperforming Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDR	83,954
Troubled Debt Restructures [Member] | Nonperforming Financial Instruments [Member] | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDR included in the balance of ALLL	14,578
Troubled Debt Restructures [Member] | Nonperforming Financial Instruments [Member] | Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDR included in the balance of ALLL	$ 3,559

Loans and Leases (Information o

Loans and Leases (Information on How Loans and Leases were Modified as a TDR) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		107	150
Total | $	$ 202,477	$ 87,423	$ 21,977
Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total | $	145,646
Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total | $	$ 62
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases			0
Commercial non-mortgage | Commercial | Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		5	8
Total | $		$ 291	$ 605
Commercial non-mortgage | Commercial | Combination Rate and Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		8	9
Total | $		$ 765	$ 352
Commercial non-mortgage | Commercial | Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		19	12
Total | $		$ 52,070	$ 14,160
Commercial real estate | Commercial | Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		0	1
Total | $		$ 0	$ 183
Commercial real estate | Commercial | Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		0	1
Total | $		$ 0	$ 1,582
Residential
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases	2
Residential | Consumer | Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		2	1
Total | $		$ 1,185	$ 99
Residential | Consumer | Combination Rate and Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		2	2
Total | $		$ 133	$ 401
Residential | Consumer | Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		8	3
Total | $		$ 3,158	$ 280
Home equity | Consumer | Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		0	85
Total | $		$ 0	$ 1,809
Home equity | Consumer | Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		1	0
Total | $		$ 74	$ 0
Home equity | Consumer | Combination Rate and Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		21	6
Total | $		$ 2,623	$ 1,025
Home equity | Consumer | Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		37	22
Total | $		$ 2,134	$ 1,481
Commercial non-mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases	3
Equipment Financing | Commercial | Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		3	0
Total | $		$ 1,692	$ 0
Asset-Based | Commercial | Other Concessions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases		1	0
Total | $		$ 23,298	$ 0

Loans and Leases (Investments i

Loans and Leases (Investments in TDRs, Segregated by Risk Rating Exposure) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs		$ 194,822
Total Loans and Leases	$ 50,726,052	49,764,426
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	6,915,688	11,169,564
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	10,018,134	5,661,880
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	4,592,545	3,487,488
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	2,641,163	3,539,935
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	2,734,340	2,445,305
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	6,261,024	5,530,594
Financing Receivable, Excluding Accrued Interest, Revolving	7,766,940	8,269,185
Total Loans and Leases	40,929,834	40,103,951
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	4,957
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	7,637
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	14,392
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	6,958
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	20,216
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	50,349
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	104,509
Commercial | Commercial non-mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,666,477	5,287,261
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,253,662	1,979,460
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,455,632	1,057,097
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	772,695	829,845
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	654,814	678,464
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	983,268	804,822
Financing Receivable, Excluding Accrued Interest, Revolving	6,098,927	5,755,846
Total Loans and Leases	16,885,475	16,392,795
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	325
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	7,637
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	1,775
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	512
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	969
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	4,391
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	15,609
Commercial | Asset-based
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	23,658	19,659
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	763	3,901
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	9,424
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	15,904
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	8,286	5,163
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	34,999	55,553
Financing Receivable, Excluding Accrued Interest, Revolving	1,490,135	1,712,038
Total Loans and Leases	1,557,841	1,821,642
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	13,189
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	3,900
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	17,089
Commercial | Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,292,080	3,443,032
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,523,279	2,258,126
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,855,013	1,563,665
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,242,555	1,674,603
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,275,687	1,153,170
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	3,203,270	2,805,735
Financing Receivable, Excluding Accrued Interest, Revolving	177,878	98,832
Total Loans and Leases	13,569,762	12,997,163
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	4,632
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	12,617
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	3,813
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	2,754
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	38,569
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	62,385
Commercial | Multi-family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	1,597,599	2,030,657
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,934,100	1,057,705
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,041,416	507,447
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	443,252	694,161
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	607,499	497,552
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1,964,104	1,773,967
Financing Receivable, Excluding Accrued Interest, Revolving	0	60,493
Total Loans and Leases	7,587,970	6,621,982
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	3,447
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	3,447
Commercial | Warehouse lending
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Revolving		641,976
Total Loans and Leases	0	641,976
Commercial | Equipment Financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	335,874	388,955
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	306,330	362,688
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	240,484	349,855
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	182,661	325,422
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	188,054	110,956
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	75,383	90,517
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Total Loans and Leases	1,328,786	1,628,393
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	2,633
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	3,304
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	42
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	5,979
(1) - (6) Pass [Member] | Commercial | Commercial non-mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,602,444	5,154,781
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,089,327	1,952,158
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,371,139	965,975
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	711,362	792,977
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	610,199	593,460
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	952,097	780,200
Financing Receivable, Excluding Accrued Interest, Revolving	5,970,588	5,670,532
Total Loans and Leases	16,307,156	15,910,083
(1) - (6) Pass [Member] | Commercial | Asset-based
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	23,007	19,659
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	3,901
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	9,424
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	14,413
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3,280	5,163
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	34,999	55,553
Financing Receivable, Excluding Accrued Interest, Revolving	1,333,271	1,551,250
Total Loans and Leases	1,394,557	1,659,363
(1) - (6) Pass [Member] | Commercial | Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,265,428	3,420,635
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,502,425	2,246,672
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,831,005	1,556,185
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,195,732	1,605,869
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,193,642	1,058,730
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	3,112,770	2,681,052
Financing Receivable, Excluding Accrued Interest, Revolving	176,668	97,832
Total Loans and Leases	13,277,670	12,666,975
(1) - (6) Pass [Member] | Commercial | Multi-family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	1,597,599	1,992,980
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,934,100	1,057,705
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,041,416	507,065
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	442,888	694,066
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	595,676	444,564
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1,920,618	1,748,337
Financing Receivable, Excluding Accrued Interest, Revolving	0	51,655
Total Loans and Leases	7,532,297	6,496,372
(1) - (6) Pass [Member] | Commercial | Warehouse lending
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Revolving		641,976
Total Loans and Leases		641,976
(1) - (6) Pass [Member] | Commercial | Equipment Financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	335,874	388,641
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	297,186	345,792
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	232,304	331,419
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	176,061	308,441
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	183,679	98,874
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	69,927	83,264
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Total Loans and Leases	1,295,031	1,556,431
(7) Special Mention [Member] | Commercial | Commercial non-mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	15,184	104,277
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	60,240	15,598
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	61,235	21,168
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	33,111	263
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0	14,370
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	720	7,770
Financing Receivable, Excluding Accrued Interest, Revolving	48,561	40,142
Total Loans and Leases	219,051	203,588
(7) Special Mention [Member] | Commercial | Asset-based
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	651	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	763	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3,676	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Revolving	29,610	80,476
Total Loans and Leases	34,700	80,476
(7) Special Mention [Member] | Commercial | Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	850	21,878
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,675	8,995
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	14,463	7,264
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	31,405	37,570
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	23,443	47,419
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	37,688	66,652
Financing Receivable, Excluding Accrued Interest, Revolving	1,210	1,000
Total Loans and Leases	113,734	190,778
(7) Special Mention [Member] | Commercial | Multi-family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	37,677
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	95
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	260	40,307
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	35,942	726
Financing Receivable, Excluding Accrued Interest, Revolving	0	8,838
Total Loans and Leases	36,202	87,643
(7) Special Mention [Member] | Commercial | Equipment Financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	185
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	116	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	11,965
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	90	6,775
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0	25
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Total Loans and Leases	206	18,950
(8) Substandard [Member] | Commercial | Commercial non-mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	48,849	28,203
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	104,087	11,704
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	23,258	69,954
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	28,222	36,604
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	44,612	70,634
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	30,426	16,852
Financing Receivable, Excluding Accrued Interest, Revolving	79,778	41,917
Total Loans and Leases	359,232	275,868
(8) Substandard [Member] | Commercial | Asset-based
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	1,491
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,330	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Revolving	127,254	80,312
Total Loans and Leases	128,584	81,803
(8) Substandard [Member] | Commercial | Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	25,802	519
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	16,179	2,459
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	9,545	216
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	15,418	31,163
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	58,602	47,021
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	52,812	57,997
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Total Loans and Leases	178,358	139,375
(8) Substandard [Member] | Commercial | Multi-family
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	382
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	364	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	11,563	12,681
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	7,544	24,904
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Total Loans and Leases	19,471	37,967
(8) Substandard [Member] | Commercial | Equipment Financing
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	314
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	9,144	16,711
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	8,064	18,436
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	6,600	5,016
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	4,285	5,307
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	5,456	7,228
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Total Loans and Leases	33,549	53,012
(9) Doubtful [Member] | Commercial | Commercial non-mortgage
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	8	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	1
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	25	0
Financing Receivable, Excluding Accrued Interest, Revolving	0	3,255
Total Loans and Leases	$ 36	3,256
(9) Doubtful [Member] | Commercial | Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year		1
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year		34
Financing Receivable, Excluding Accrued Interest, Revolving		0
Total Loans and Leases		$ 35

Loans and Leases (Credit Qualit

Loans and Leases (Credit Quality Indicators) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Total Loans and Leases	$ 50,726,052	$ 49,764,426
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	816,641	2,042,000
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,019,764	2,399,022
Total Loans and Leases	9,796,218	9,660,475
Financing Receivable, Excluding Accrued Interest, Revolving	1,133,076	1,268,535
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	2,286,113	960,281
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	462,450	126,240
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	893,040	454,877
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	2,185,134	2,409,520
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	3,263
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	11
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	470
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	218
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	634
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	8,107
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	12,703
Consumer | Consumer Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,470	2,740
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,778	3,663
Total Loans and Leases	51,340	63,948
Financing Receivable, Excluding Accrued Interest, Revolving	39,001	40,451
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	2,947	5,349
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	2,486	2,438
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	2,064	8,694
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	594	613
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	3,263
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	7
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	2
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	218
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	377
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	363
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	4,230
Consumer | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	742,719	1,965,372
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,949,928	2,304,919
Total Loans and Leases	8,227,923	7,963,420
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	2,201,633	901,353
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	441,840	94,152
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	843,276	424,742
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	2,048,527	2,272,882
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	387
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	153
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	4,630
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	5,170
Consumer | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	71,452	73,888
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	68,058	90,440
Total Loans and Leases	1,516,955	1,633,107
Financing Receivable, Excluding Accrued Interest, Revolving	1,094,075	1,228,084
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	81,533	53,579
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	18,124	29,650
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	47,700	21,441
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	136,013	136,025
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	4
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	81
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	104
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	3,114
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	3,303
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	6,915,688	11,169,564
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	10,018,134	5,661,880
Total Loans and Leases	40,929,834	40,103,951
Financing Receivable, Excluding Accrued Interest, Revolving	7,766,940	8,269,185
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	4,592,545	3,487,488
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	2,734,340	2,445,305
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	2,641,163	3,539,935
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	6,261,024	5,530,594
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	4,957
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	7,637
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	14,392
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	6,958
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	20,216
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	50,349
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	104,509
Commercial | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,292,080	3,443,032
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,523,279	2,258,126
Total Loans and Leases	13,569,762	12,997,163
Financing Receivable, Excluding Accrued Interest, Revolving	177,878	98,832
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,855,013	1,563,665
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,275,687	1,153,170
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,242,555	1,674,603
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	3,203,270	2,805,735
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	4,632
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	12,617
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	3,813
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	2,754
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	38,569
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	62,385
Commercial | Commercial real estate | (7) Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	850	21,878
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,675	8,995
Total Loans and Leases	113,734	190,778
Financing Receivable, Excluding Accrued Interest, Revolving	1,210	1,000
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	14,463	7,264
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	23,443	47,419
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	31,405	37,570
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	37,688	66,652
Commercial | Commercial real estate | (1) - (6) Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,265,428	3,420,635
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,502,425	2,246,672
Total Loans and Leases	13,277,670	12,666,975
Financing Receivable, Excluding Accrued Interest, Revolving	176,668	97,832
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,831,005	1,556,185
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,193,642	1,058,730
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,195,732	1,605,869
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	3,112,770	2,681,052
Commercial | Commercial real estate | (8) Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	25,802	519
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	16,179	2,459
Total Loans and Leases	178,358	139,375
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	9,545	216
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	58,602	47,021
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	15,418	31,163
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	52,812	57,997
Commercial | Commercial real estate | (9) Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year		0
Total Loans and Leases		35
Financing Receivable, Excluding Accrued Interest, Revolving		0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year		1
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year		34
Commercial | Commercial non-mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,666,477	5,287,261
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,253,662	1,979,460
Total Loans and Leases	16,885,475	16,392,795
Financing Receivable, Excluding Accrued Interest, Revolving	6,098,927	5,755,846
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,455,632	1,057,097
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	654,814	678,464
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	772,695	829,845
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	983,268	804,822
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	325
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	7,637
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	1,775
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	512
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	969
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	4,391
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	15,609
Commercial | Commercial non-mortgage | (7) Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	15,184	104,277
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	60,240	15,598
Total Loans and Leases	219,051	203,588
Financing Receivable, Excluding Accrued Interest, Revolving	48,561	40,142
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	61,235	21,168
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	0	14,370
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	33,111	263
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	720	7,770
Commercial | Commercial non-mortgage | (1) - (6) Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	2,602,444	5,154,781
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	4,089,327	1,952,158
Total Loans and Leases	16,307,156	15,910,083
Financing Receivable, Excluding Accrued Interest, Revolving	5,970,588	5,670,532
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,371,139	965,975
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	610,199	593,460
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	711,362	792,977
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	952,097	780,200
Commercial | Commercial non-mortgage | (8) Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	48,849	28,203
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	104,087	11,704
Total Loans and Leases	359,232	275,868
Financing Receivable, Excluding Accrued Interest, Revolving	79,778	41,917
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	23,258	69,954
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	44,612	70,634
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	28,222	36,604
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	30,426	16,852
Commercial | Commercial non-mortgage | (9) Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	8	0
Total Loans and Leases	36	3,256
Financing Receivable, Excluding Accrued Interest, Revolving	0	3,255
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	1
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	25	0
Commercial | Asset-based
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	23,658	19,659
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	763	3,901
Total Loans and Leases	1,557,841	1,821,642
Financing Receivable, Excluding Accrued Interest, Revolving	1,490,135	1,712,038
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	9,424
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	8,286	5,163
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	15,904
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	34,999	55,553
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	13,189
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	3,900
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	17,089
Commercial | Asset-based | (7) Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	651	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	763	0
Total Loans and Leases	34,700	80,476
Financing Receivable, Excluding Accrued Interest, Revolving	29,610	80,476
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3,676	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0	0
Commercial | Asset-based | (1) - (6) Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	23,007	19,659
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	3,901
Total Loans and Leases	1,394,557	1,659,363
Financing Receivable, Excluding Accrued Interest, Revolving	1,333,271	1,551,250
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	9,424
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3,280	5,163
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	14,413
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	34,999	55,553
Commercial | Asset-based | (8) Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Total Loans and Leases	128,584	81,803
Financing Receivable, Excluding Accrued Interest, Revolving	127,254	80,312
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,330	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	1,491
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0	0
Commercial | Multi-family
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	1,597,599	2,030,657
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,934,100	1,057,705
Total Loans and Leases	7,587,970	6,621,982
Financing Receivable, Excluding Accrued Interest, Revolving	0	60,493
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,041,416	507,447
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	607,499	497,552
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	443,252	694,161
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1,964,104	1,773,967
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	3,447
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	3,447
Commercial | Multi-family | (7) Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	37,677
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Total Loans and Leases	36,202	87,643
Financing Receivable, Excluding Accrued Interest, Revolving	0	8,838
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	260	40,307
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	95
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	35,942	726
Commercial | Multi-family | (1) - (6) Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	1,597,599	1,992,980
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,934,100	1,057,705
Total Loans and Leases	7,532,297	6,496,372
Financing Receivable, Excluding Accrued Interest, Revolving	0	51,655
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,041,416	507,065
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	595,676	444,564
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	442,888	694,066
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1,920,618	1,748,337
Commercial | Multi-family | (8) Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	0
Total Loans and Leases	19,471	37,967
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	0	382
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	11,563	12,681
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	364	0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	7,544	24,904
Commercial | Warehouse lending
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year		0
Total Loans and Leases	0	641,976
Financing Receivable, Excluding Accrued Interest, Revolving		641,976
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year		0
Commercial | Warehouse lending | (1) - (6) Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year		0
Total Loans and Leases		641,976
Financing Receivable, Excluding Accrued Interest, Revolving		641,976
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year		0
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year		0
Commercial | Equipment Financing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	335,874	388,955
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	306,330	362,688
Total Loans and Leases	1,328,786	1,628,393
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	240,484	349,855
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	188,054	110,956
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	182,661	325,422
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	75,383	90,517
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff	2,633
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff	3,304
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff	42
Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff	0
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff	5,979
Commercial | Equipment Financing | (7) Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	0
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	0	185
Total Loans and Leases	206	18,950
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	116	0
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	90	6,775
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	0	11,965
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	0	25
Commercial | Equipment Financing | (1) - (6) Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	335,874	388,641
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	297,186	345,792
Total Loans and Leases	1,295,031	1,556,431
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	232,304	331,419
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	183,679	98,874
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	176,061	308,441
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	69,927	83,264
Commercial | Equipment Financing | (8) Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	0	314
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	9,144	16,711
Total Loans and Leases	33,549	53,012
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	8,064	18,436
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	4,285	5,307
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	6,600	5,016
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	5,456	7,228
579 and below [Member] | Consumer | Consumer Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	125	169
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	97	101
Total Loans and Leases	913	1,179
Financing Receivable, Excluding Accrued Interest, Revolving	590	707
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	61	29
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	28	36
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	11	116
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	1	21
579 and below [Member] | Consumer | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	6,909	52,464
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	52,690	3,693
Total Loans and Leases	253,079	206,453
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	11,749	2,057
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	128,714	1,299
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,345	84,032
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	51,672	62,908
579 and below [Member] | Consumer | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	696	426
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,109	386
Total Loans and Leases	44,573	35,237
Financing Receivable, Excluding Accrued Interest, Revolving	34,242	27,814
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,079	651
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	552	563
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	576	661
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	6,319	4,736
800+ [Member] | Consumer | Consumer Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	432	495
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	356	218
Total Loans and Leases	28,921	21,801
Financing Receivable, Excluding Accrued Interest, Revolving	25,699	19,196
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,913	544
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	255	247
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	189	1,045
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	77	56
800+ [Member] | Consumer | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	214,446	527,408
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	847,009	954,568
Total Loans and Leases	3,660,907	3,137,860
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,096,109	469,518
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	141,919	28,361
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	451,307	160,596
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	910,117	997,409
800+ [Member] | Consumer | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	27,047	25,475
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	27,439	35,129
Total Loans and Leases	571,787	627,009
Financing Receivable, Excluding Accrued Interest, Revolving	391,616	465,318
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	35,927	25,612
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	8,110	12,545
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	25,586	7,578
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	56,062	55,352
740-799 [Member] | Consumer | Consumer Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	1,318	888
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	586	2,624
Total Loans and Leases	11,371	21,488
Financing Receivable, Excluding Accrued Interest, Revolving	7,180	12,218
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	486	1,959
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	690	941
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	730	2,494
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	381	364
740-799 [Member] | Consumer | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	363,696	963,026
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	703,568	946,339
Total Loans and Leases	2,848,841	3,066,028
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	755,750	311,295
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	112,303	43,684
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	279,946	111,913
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	633,578	689,771
740-799 [Member] | Consumer | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	24,772	26,743
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	20,069	35,178
Total Loans and Leases	481,150	526,380
Financing Receivable, Excluding Accrued Interest, Revolving	355,926	398,692
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	27,147	17,621
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	5,158	7,765
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	13,888	8,111
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	34,190	32,270
670 to 739 [Member] | Consumer | Consumer Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	526	977
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	570	603
Total Loans and Leases	7,273	15,564
Financing Receivable, Excluding Accrued Interest, Revolving	3,549	6,107
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	358	2,480
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,210	1,041
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	981	4,238
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	79	118
670 to 739 [Member] | Consumer | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	137,460	381,515
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	293,699	350,671
Total Loans and Leases	1,214,327	1,301,688
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	292,255	103,999
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	48,412	18,451
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	95,838	62,365
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	346,663	384,687
670 to 739 [Member] | Consumer | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	15,857	18,396
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	15,655	16,679
Total Loans and Leases	327,725	344,205
Financing Receivable, Excluding Accrued Interest, Revolving	242,189	259,646
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	15,389	8,175
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	3,189	7,614
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	5,992	3,635
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	29,454	30,060
580-669 [Member] | Consumer | Consumer Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	69	211
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	169	117
Total Loans and Leases	2,862	3,916
Financing Receivable, Excluding Accrued Interest, Revolving	1,983	2,223
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	129	337
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	303	173
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	153	801
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	56	54
580-669 [Member] | Consumer | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	20,208	40,959
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	52,962	49,648
Total Loans and Leases	250,769	251,391
Financing Receivable, Excluding Accrued Interest, Revolving	0	0
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	45,770	14,484
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	10,492	2,357
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	14,840	5,836
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	106,497	138,107
580-669 [Member] | Consumer | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year	3,080	2,848
Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year	3,786	3,068
Total Loans and Leases	91,720	100,276
Financing Receivable, Excluding Accrued Interest, Revolving	70,102	76,614
Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year	1,991	1,520
Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year	1,115	1,163
Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year	1,658	1,456
Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year	$ 9,988	$ 13,607

Loans and Leases - (Summary of

Loans and Leases - (Summary of Amortized Cost Basis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 202,477	$ 87,423	$ 21,977
% of Total Class	0.40%
Accrued interest receivable	$ 700
Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	62
Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	145,646
Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8,120
CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	18,818
CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	29,371
CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	35
CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	425
Commercial non-mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 133,135
% of Total Class	0.80%
Commercial non-mortgage | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Commercial non-mortgage | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 96,895
Extended term by a weighted average	1 year 3 months 18 days
Commercial non-mortgage | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 5,858
Extended term by a weighted average	6 months
Commercial non-mortgage | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,062
Reduced weighted average interest rate	1.80%
Extended term by a weighted average	1 year 4 months 24 days
Commercial non-mortgage | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 28,860
Extended term by a weighted average	1 year 1 month 6 days
Payment deferrals weighted average	1 year
Commercial non-mortgage | CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 35
Reduced weighted average interest rate	2%
Payment deferrals weighted average	6 months
Commercial non-mortgage | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 425
Reduced weighted average interest rate	2%
Extended term by a weighted average	6 months
Payment deferrals weighted average	6 months
Asset-based
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 45,042
% of Total Class	2.90%
Asset-based | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Asset-based | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 45,042
Extended term by a weighted average	8 months 12 days
Asset-based | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Asset-based | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Asset-based | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Asset-based | CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Asset-based | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 20,882
% of Total Class	0.20%
Commercial real estate | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Commercial real estate | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 3,090
Extended term by a weighted average	2 years 2 months 12 days
Commercial real estate | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 174
Extended term by a weighted average	3 months 18 days
Commercial real estate | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 17,107
Reduced weighted average interest rate	2.40%
Extended term by a weighted average	3 years
Commercial real estate | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 511
Extended term by a weighted average	6 months
Payment deferrals weighted average	6 months
Commercial real estate | CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Commercial real estate | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Equipment financing | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Extended term by a weighted average	6 months
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,126
% of Total Class	0%
Residential | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Residential | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 186
Extended term by a weighted average	2 years 9 months 18 days
Residential | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 804
Extended term by a weighted average	1 year
Residential | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 136
Reduced weighted average interest rate	0.30%
Extended term by a weighted average	17 years 10 months 24 days
Residential | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Residential | CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Residential | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Equipment Financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,641
% of Total Class	0.10%
Equipment Financing | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Equipment Financing | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 357
Extended term by a weighted average	4 years 6 months
Equipment Financing | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 1,284
Equipment Financing | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Equipment Financing | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Equipment Financing | CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Equipment Financing | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 651
% of Total Class	0%
Home equity | Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 62
Reduced weighted average interest rate	0.50%
Home equity | Term Extension
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 76
Extended term by a weighted average	10 years 1 month 6 days
Home equity | Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Home equity | CombinationTerm Extension & Interest Rate Reduction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 513
Reduced weighted average interest rate	2.10%
Extended term by a weighted average	16 years 9 months 18 days
Home equity | CombinationTerm Extension & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0
Home equity | CombinationInterest Rate Reduction & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Home equity | CombinationTerm Extension, Interest Rate Reduction, & Payment Delay
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0

Loans and Leases (Impaired Coll

Loans and Leases (Impaired Collateral) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Collateral Pledged [Member] | Commercial
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 66,100	$ 43,800
Collateral Pledged [Member] | Consumer
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	22,700	45,200
Collateral Value [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 93,700	$ 108,000

Loans and Leases (Nonaccrual) (

Loans and Leases (Nonaccrual) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	$ 208,525	$ 197,441
Total  Past Due and Non-accrual	39,037	42,059
Interest on non-accrual loans that would have been recorded as additional interest income	22,900	16,900	$ 11,000
Commercial
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	179,134	143,945
Total  Past Due and Non-accrual	25,661	16,419
Commercial | Commercial non-mortgage
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	122,855	71,884
Total  Past Due and Non-accrual	20,066	12,598
Commercial | Asset-based
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	35,068	20,024
Total  Past Due and Non-accrual	1,330	1,491
Commercial | Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	11,383	39,057
Total  Past Due and Non-accrual	2,681	90
Consumer
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	29,391	53,496
Total  Past Due and Non-accrual	13,376	25,640
Consumer | Residential
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	5,704	25,424
Total  Past Due and Non-accrual	856	10,442
Consumer | Home equity
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	23,545	27,924
Total  Past Due and Non-accrual	12,471	15,193
Consumer | 522291 Consumer Lending [Member]
Financing Receivable, Nonaccrual [Line Items]
Non-accrual	142	148
Total  Past Due and Non-accrual	$ 49	$ 5

Transfers of Financial Assets_2

Transfers of Financial Assets (Loans sold) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Servicing Assets at Fair Value [Line Items]
Net gain on sale	$ 1,240	$ 705	$ 6,219
Consumer
Servicing Assets at Fair Value [Line Items]
Net gain on sale	1,240	705	6,219
Ancillary Fee Income Generated by Servicing Financial Assets, Amount	68	219	1,440
Residential Mortgage Loans Servicing Retained [Member] | Consumer
Servicing Assets at Fair Value [Line Items]
Proceeds from sale	6,499	32,056	237,834
Residential | Consumer
Servicing Assets at Fair Value [Line Items]
Proceeds from sale	13,882	36,335	247,634
Fair value option adjustment	46	(94)	(413)
Gain (Loss) on Sale of Mortgage Loans	$ 1,126	$ 580	$ 5,192

Transfers of Financial Assets_3

Transfers of Financial Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Proceeds from loans not originated for sale	$ 625,968	$ 679,693	$ 82,187
Net gain on sale	$ 1,240	705	6,219
Ancillary Fee Income, Servicing Financial Asset, Statement of Income or Comprehensive Income [Extensible Enumeration]	Net gain on sale
Mortgage Loans, Unpaid Principal Balance	$ 1,400,000
Mortgage servicing assets	8,300
Residential
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Retained servicing rights	1,800,000	2,000,000
Bank servicing fees	4,000	5,900	1,700
Commercial Loan [Member]
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Proceeds from loans not originated for sale	626,000	679,700	82,200
Net gain on sale	$ 900	$ 3,300	$ 3,900

Transfers of Financial Assets S

Transfers of Financial Assets Servicing Assets at Amortized Cost Roll Forward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Beginning balance	$ 9,515	$ 9,237	$ 13,422
Additions	71	289	2,053
Amortization	(1,063)	(870)	(5,593)
Adjustment to valuation allowance	0	0	(645)
Ending balance	8,523	9,515	9,237
Sterling
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Additions	$ 0	$ 859	$ 0

Premises and Equipment - Summar

Premises and Equipment - Summary of Premises and Equipment (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) holding	Dec. 31, 2021 USD ($)
Property, Plant and Equipment [Abstract]
Land	$ 73,916	$ 73,916	$ 73,916
Buildings and improvements	107,794	107,794	106,180
Leasehold improvements	88,065	88,065	84,477
Furniture, fixtures, and equipment	68,680	68,680	71,542
Data processing equipment and software	94,030	94,030	128,153
Property and equipment	432,485	432,485	464,268
Less: Accumulated depreciation and amortization	(186,365)	(186,365)	(225,152)
Premises and equipment, net	246,120	246,120	239,116
ROU lease assets, net	183,441	183,441	191,068
Property and equipment, net	429,561	429,561	430,184
Depreciation and amortization		34,700	41,700	$ 31,400
Loss on disposal of property and equipment	(700)	$ 4,600	$ 6,300
Number of locations closed | holding			14
Reduction in real estate			45%
Write-down of real estate			$ 1,800
Disposal Group, Including Discontinued Operation, Assets, Current			$ 4,800
Cash proceeds from sale of business	$ 4,100

Leasing - Narrative (Details)

Leasing - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Leased assets impairment loss	$ 0	$ 23.1		$ 1.2
Commercial | Equipment financing
Lessee, Lease, Description [Line Items]
Sales-type and direct financing lessor activities	$ 18.7	$ 15.4	$ 7.5
Minimum
Lessee, Lease, Description [Line Items]
Financing leases, term	1 year
Lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Financing leases, term	10 years
Lease term	15 years

Leasing - Summary of Net Invest

Leasing - Summary of Net Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Lease receivables	$ 347,827	$ 330,690
Unguaranteed residual values	60,747	100,368
Total net investment	$ 408,574	$ 431,058

Leasing - Summary of Net Inve_2

Leasing - Summary of Net Investment Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
2024	$ 116,506
2025	107,211
2026	98,157
2027	51,058
2028	31,179
Thereafter	44,911
Total lease payments receivable	449,022
Present value adjustment	(40,448)
Total net investment	$ 408,574	$ 431,058

Leasing - Operating ROU Assets

Leasing - Operating ROU Assets and Lease Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Jan. 31, 2022
Leases [Abstract]
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net	Property and equipment, net	Property and equipment, net
ROU lease assets	$ 183,441	$ 191,068
Operating lease liabilities	$ 222,439	$ 239,281
Operating lease liabilities, location	Accrued expenses and other liabilities	Accrued expenses and other liabilities	Accrued expenses and other liabilities

Leasing - Lease Cost (Details)

Leasing - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lease, Cost [Abstract]
Operating and variable lease costs	$ 38,497	$ 44,654	$ 30,936
Sublease income	(223)	(1,383)	(554)
Total operating lease expense	38,274	43,271	30,382
Cash paid for amounts included in the measurement of operating lease liabilities	37,615	44,767	30,487
ROU lease assets obtained in exchange for operating lease liabilities	$ 22,989	$ 27,897	$ 15,226
Weighted-average remaining lease term (in years)	7 years 5 months 15 days	7 years 8 months 19 days	7 years 6 months
Weighted-average discount rate	2.96%	2.65%	3.04%

Leasing - Maturity of Operating

Leasing - Maturity of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Lessee, Operating Lease, Liability, to be Paid, Rolling Maturity [Abstract]
2024	$ 38,575
2025	39,449
2026	35,665
2027	31,128
2028	26,999
Thereafter	81,918
Total operating lease payments	253,734
Present value adjustment	31,295
Operating lease liabilities	$ 222,439	$ 239,281

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Balance, beginning of period	$ 2,514,104	$ 538,373
Balance, end of period	2,631,465	2,514,104
Sterling
Goodwill [Roll Forward]
Goodwill acquired	(25,561)	(1,939,765)
Bend
Goodwill [Roll Forward]
Goodwill acquired	(294)	(35,966)
interLINK
Goodwill [Roll Forward]
Goodwill acquired	$ (143,216)	$ 0

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Gross Carrying Value And Accumulated Amortization Of Other Intangible Assets) (Detail) - USD ($) $ in Thousands	Jan. 11, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 2,631,465	$ 2,514,104	$ 538,373
Gross Carrying Amount		301,037	261,037
Accumulated Amortization		(97,902)	(61,695)
Net Carrying Amount		203,135	199,342
interLINK
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 143,200
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		146,037	146,037
Accumulated Amortization		(53,986)	(36,710)
Net Carrying Amount		92,051	109,327
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		151,000	115,000
Accumulated Amortization		(43,116)	(24,985)
Net Carrying Amount		107,884	90,015
Customer Relationships | interLINK
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, useful life	10 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets	$ 36,000
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		4,000	0
Accumulated Amortization		(800)	0
Net Carrying Amount		$ 3,200	$ 0
Noncompete Agreements | interLINK
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets, useful life	5 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets	$ 4,000

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets (Schedule Of Expected Future Amortization Expense) (Detail) $ in Thousands	Dec. 31, 2023 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2020	$ 29,618
2021	25,956
2022	25,565
2023	25,565
2024	23,216
Thereafter	$ 73,215

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ 219,548	$ 170,779	$ 109,621
State and local	50,750	52,579	20,374
Total current	270,298	223,358	129,995
Deferred:
Federal	(43,615)	(45,421)	(9,844)
State and local	(10,019)	(24,243)	4,846
Total deferred	(53,634)	(69,664)	(4,998)
Total:
Total federal	175,933	125,358	99,777
Total state and local	40,731	28,336	25,220
Income tax expense and effective tax rate	$ 216,664	$ 153,694	$ 124,997

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Loss Carryforwards [Line Items]
Net tax credits	$ 11,900	$ 14,000	$ 2,600
Benefit from operating loss carryforwards	200	10,300	400
DTA valuation allowance adjustment, net	(368)	(9,874)	0
Increase (decrease) in deferred income taxes	(2,400)
Deferred tax expense (benefit)	(53,634)	(69,664)	(4,998)
Tax benefit directly allocated to shareholder's equity	(49,700)
Valuation allowance	28,746	29,176
Unrecognized deferred tax liability for thrift bad-debt reserves	63,200	63,200
Cumulative taxable temporary differences	233,100	233,100
Unrecognized tax benefits that would impact effective tax rate	12,400	9,100	3,500
Interest and penalties	1,800	100	$ (300)
Accrued interest and penalties related to UTBs	3,800	$ 2,000
Accounting Standards Update 2022-02
Operating Loss Carryforwards [Line Items]
Increase (Decrease) in Deferred Income Taxes, Adjustment to Equity	1,600
Sterling Merger and Bend Acquisition
Operating Loss Carryforwards [Line Items]
Deferred tax liability, net	7,900
SALT
Operating Loss Carryforwards [Line Items]
Valuation allowance	28,600
Deferred tax assets, net operating loss carryforwards subject to expiration	486,600
Federal
Operating Loss Carryforwards [Line Items]
Valuation allowance	600
Deferred tax assets, net operating loss carryforwards subject to expiration	400
SALT
Operating Loss Carryforwards [Line Items]
Deferred tax assets, operating loss carryforwards	1,100,000
Federal
Operating Loss Carryforwards [Line Items]
Deferred tax assets, operating loss carryforwards	16,800
Minimum
Operating Loss Carryforwards [Line Items]
Decrease in unrecognized tax benefits reasonably possible	400
Maximum
Operating Loss Carryforwards [Line Items]
Decrease in unrecognized tax benefits reasonably possible	$ 9,300

Income Taxes - Schedule of Effe

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income tax expense at federal statutory rate	$ 227,746	$ 167,575	$ 112,111
SALT expense, net of federal	32,177	32,259	19,924
Tax-exempt interest income, net	(44,473)	(35,371)	(6,814)
Increase in cash surrender value of life insurance	(5,469)	(6,122)	(3,030)
Non-deductible FDIC deposit insurance premiums	10,693	5,581	2,064
Low income housing tax credits and other benefits, net	(3,866)	(7,627)	(615)
Non-deductible compensation expense	4,167	7,948	786
Non-deductible merger-related expenses, excluding compensation	45	2,717	3,451
DTA valuation allowance adjustment, net	(368)	(9,874)	0
Other, net	(3,988)	(3,392)	(2,880)
Income tax expense and effective tax rate	$ 216,664	$ 153,694	$ 124,997
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income tax expense at federal statutory rate	21%	21%	21%
SALT expense, net of federal	3%	4.10%	3.70%
Tax-exempt interest income, net	(4.10%)	(4.40%)	(1.30%)
Increase in cash surrender value of life insurance	(0.50%)	(0.80%)	(0.60%)
Non-deductible FDIC deposit insurance premiums	1%	0.70%	0.40%
Low income housing tax credits and other benefits, net	(0.40%)	(1.00%)	(0.10%)
Non-deductible compensation expense	0.40%	1%	0.10%
Non-deductible merger-related expenses, excluding compensation	0%	0.30%	0.70%
DTA valuation allowance adjustment, net	0%	(1.20%)	0%
Other, net	(0.40%)	(0.40%)	(0.50%)
Income tax expense and effective tax rate	20%	19.30%	23.40%

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
ACL on loans and leases	$ 171,870	$ 161,932
Net operating loss and credit carry forwards	68,103	72,035
Compensation and employee benefit plans	46,670	55,093
Lease liabilities under operating leases	60,331	64,899
Net unrealized loss on available-for-sale securities	191,922	233,978
Other	72,546	38,314
Gross deferred tax assets	611,442	626,251
Valuation allowance	(28,746)	(29,176)
Total deferred tax assets, net of valuation allowance	582,696	597,075
Deferred tax liabilities:
ROU assets under operating leases	49,754	51,822
Equipment financing leases	54,300	74,295
Goodwill and other intangible assets	59,817	56,223
Purchase accounting and fair value adjustments	15,527	11,529
Other	34,086	31,572
Gross deferred tax liabilities	213,484	225,441
Deferred tax assets, net	$ 369,212	$ 371,634

Income Taxes - Summary of Posit

Income Taxes - Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 9,875	$ 4,249	$ 4,252
Additions as a result of tax positions taken during the current year	359	223	294
Additions as a result of tax positions taken during prior years	4,255	8,807	434
Reductions as a result of tax positions taken during prior years	0	(503)	(186)
Reductions relating to settlements with taxing authorities	0	(2,110)	(267)
Reductions as a result of lapse of statute of limitation periods	(653)	(791)	(278)
Ending balance	$ 13,836	$ 9,875	$ 4,249

Deposits (Summary Of Deposits)

Deposits (Summary Of Deposits) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deposit Liabilities [Abstract]
Demand	$ 10,732,516	$ 12,974,975
Health Savings Accounts	8,287,889	7,944,892
Checking	8,994,095	9,237,529
Money market	17,662,826	11,062,652
Savings	6,642,499	8,673,343
Time deposits	8,464,459	4,160,949
Total interest-bearing	50,051,768	41,079,365
Total deposits	60,784,284	54,054,340
Time deposits and interest-bearing checking, included in above balances, obtained through brokers	3,673,733	1,964,873
Time deposits, included in above balance, that exceed the FDIC limit	1,221,887	1,894,950
Demand deposit overdrafts reclassified as loan balances	10,432	$ 8,721
Money Market Sweep Deposits	$ 5,700,000

Deposits (Scheduled Maturities

Deposits (Scheduled Maturities Of Time Deposits) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deposit Liabilities [Abstract]
2020	$ 8,217,683
2021	138,769
2022	53,807
2023	32,865
2024	21,335
Total time deposits	$ 8,464,459	$ 4,160,949

Borrowings Borrowings - (Narrat

Borrowings Borrowings - (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Jan. 31, 2022	Oct. 30, 2020	Dec. 16, 2019
Subordinated Notes Due 2029 | Subordinated Debt | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.53%
Subordinated Notes Due 2030 | Subordinated Debt | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.69%
Sterling
Debt Instrument [Line Items]
Aggregate principal amount		$ 3,266,096	$ 225,000	$ 274,000
Fixed-to-floating rate			3.875%	4%
Long-term debt		516,881
Sterling | Subordinated Notes Due 2029 | Subordinated Debt
Debt Instrument [Line Items]
Long-term debt		281,000
Sterling | Subordinated Notes Due 2030 | Subordinated Debt
Debt Instrument [Line Items]
Long-term debt		$ 235,900

Borrowings (Summary Of Securiti

Borrowings (Summary Of Securities Sold Under Agreements To Repurchase And Other Borrowings) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets Sold under Agreements to Repurchase [Line Items]
Total securities sold under agreements to repurchase	$ 358,387	$ 282,005
Fed funds purchased	100,000	869,825
Securities sold under agreements to repurchase and other borrowings	$ 458,387	$ 1,151,830
Securities Sold under Agreements to Repurchase [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Rate (as a percent)	3.43%	0.11%
Federal Funds Purchased [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Rate (as a percent)	5.48%	4.44%
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]
Assets Sold under Agreements to Repurchase [Line Items]
Rate (as a percent)	3.88%	3.38%

Borrowings (Summary Of Advances

Borrowings (Summary Of Advances Payable To The Federal Home Loan Bank) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Federal Home Loan Bank, Advances, Maturity, Rolling Year [Abstract]
FHLB advances maturing within 1 year, Weighted-Average Contractual Coupon Rate (as a percent)	5.53%	4.40%
FHLB advances maturing after 1 but within 2 years, Weighted-Average Contractual Coupon Rate (as a percent)	0%	0%
FHLB advances maturing after 2 but within 3 years, Weighted-Average Contractual Coupon Rate (as a percent)	0%	0%
FHLB advances maturing after 3 but within 4 years, Weighted-Average Contractual Coupon Rate (as a percent)	0%	0%
FHLB advances maturing after 4 but within 5 years, Weighted-Average Contractual Coupon Rate (as a percent)	2.75%	0%
FHLB advances maturing after 5 years, Weighted-Average Contractual Coupon Rate (as a percent)	2.07%	2.09%
Federal Home Loan Bank, Advances, Weighted Average Interest Rate (as a percent)	5.52%	4.39%
Aggregate market value of assets pledged as collateral	$ 20,734,035	$ 13,692,379
Remaining borrowing capacity	12,535,423	4,291,326
FHLB advances maturing within 1 year, Total Outstanding	2,350,000	5,450,187
FHLB advances maturing after 1 but within 2 years, Total Outstanding	0	0
FHLB advances maturing after 2 but within 3 years, Total Outstanding	0	0
FHLB advances maturing after 3 but within 4 years, Total Outstanding	235	0
FHLB advances maturing after 4 but within 5 years, Total Outstanding	228	252
FHLB advances maturing after 5 years, Total Outstanding	9,555	10,113
FHLB advances	$ 2,360,018	$ 5,460,552

Borrowings (Long-Term Debt) (De

Borrowings (Long-Term Debt) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Notes and subordinated debt	$ 1,036,974	$ 1,059,778
Debt issuance cost on senior fixed-rate notes	(1,419)	(1,824)
Long-term debt	$ 1,048,820	$ 1,073,128
Long term debt, variable interest rate, percentage	8.59%	7.69%
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)		$ 33,458
Subordinated Debt
Debt Instrument [Line Items]
Debt Instrument, Unamortized Premium	$ 13,802	$ 15,930
Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Interest rate spread of LIBOR plus (as a percent)	2.95%
LIBOR
Debt Instrument [Line Items]
Interest rate spread of LIBOR plus (as a percent)		2.95%
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Notes and subordinated debt	$ 77,320	$ 77,320
Long-term Debt [Member]
Debt Instrument [Line Items]
Discount on senior fixed-rate notes	(537)	(756)
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	28,100	33,500
Subordinated Notes Due 2029 | Subordinated Debt
Debt Instrument [Line Items]
Long-Term Debt, Gross	274,000	274,000
Subordinated Notes Due 2030 | Subordinated Debt
Debt Instrument [Line Items]
Long-Term Debt, Gross	225,000	225,000
Debt Instrument, Redemption, Period One | Senior Notes
Debt Instrument [Line Items]
Notes and subordinated debt	$ 132,550	150,000
Debt instrument, stated interest rate, percentage	4.375%
Debt Instrument, Redemption, Period Two | Senior Notes
Debt Instrument [Line Items]
Notes and subordinated debt	$ 328,104	$ 333,458
Debt instrument, stated interest rate, percentage	4.10%

Stockholders' Equity - Class of

Stockholders' Equity - Class of Stock Disclosure (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	May 15, 2023	Jan. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock Outstanding, beginning balance (in shares)			174,007,573
Employee stock compensation plan activity (in shares)			(605,684)
Stock options exercised (in shares)			(75,848)
Common stock repurchase program (in shares)			2,667,149
Common Stock Outstanding, ending balance (in shares)			172,021,956
Treasury Stock, Common, Shares			10,756,089	8,770,472
Senior Notes Due 2024 | Senior Notes
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Repurchased and Retired During Period, Value	$ 17.5
Shares Repurchased And Retired, Price Per Share	$ 0.96
Gain (Loss) on Extinguishment of Debt			$ 0.7
Sterling
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)		87,965,239
Preferred Stock Series F Issued
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares, beginning balance (in shares)			6,000
Employee stock compensation plan activity (in shares)			0
Stock options exercised (in shares)			0
Common stock repurchase program (in shares)			0
Shares, ending balance (in shares)			6,000
Preferred Stock Series G Issued
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares, beginning balance (in shares)			135,000
Employee stock compensation plan activity (in shares)			0
Stock options exercised (in shares)			0
Common stock repurchase program (in shares)
Shares, ending balance (in shares)			135,000
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares, beginning balance (in shares)			182,778,045
Employee stock compensation plan activity (in shares)			0
Stock options exercised (in shares)			0
Common stock repurchase program (in shares)			0
Shares, ending balance (in shares)			182,778,045
Treasury Stock, Common
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee stock compensation plan activity (in shares)			(605,684)
Stock options exercised (in shares)			(75,848)
Common stock repurchase program (in shares)			2,667,149
Treasury Stock, Common, Shares			10,756,089	8,770,472

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Jan. 31, 2022 $ / shares shares	Dec. 12, 2017 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)	Apr. 19, 2021 shares
Class of Stock [Line Items]
Stock repurchase program, authorized amount | $			$ 600,000
Treasury stock acquired, average cost per share (in usd per share) | $ / shares			$ 40.49
Treasury stock acquired, value | $			$ 107,984	$ 322,103	$ 0
Stock repurchase program, remaining authorized repurchase amount | $		$ 6,000	$ 293,400
Preferred stock, shares authorized			3,000,000	3,000,000
Depositary shares, ownership of preferred shares			0.001
Value per share (in dollars per share) | $ / shares			$ 0.01	$ 0.01
Common stock repurchase program (in shares)			2,667,149
Employee Stock Compensation Plan
Class of Stock [Line Items]
Treasury stock acquired, average cost per share (in usd per share) | $ / shares			$ 51.48
Treasury stock acquired, value | $			$ 16,300
Common stock repurchase program (in shares)			315,729
Sterling
Class of Stock [Line Items]
Preferred stock, shares authorized	400,000,000					200,000,000
Common Stock
Class of Stock [Line Items]
Common stock repurchase program (in shares)			0
Preferred Stock Series F Issued
Class of Stock [Line Items]
Preferred stock, dividend rate (as a percent)		5.25%
Value per share (in dollars per share) | $ / shares		$ 0.01
Preferred stock, liquidation preference per share (in usd per share) | $ / shares		$ 25,000
Common stock repurchase program (in shares)			0
Preferred Stock Series G Issued
Class of Stock [Line Items]
Preferred stock, dividend rate (as a percent)			6.50%
Value per share (in dollars per share) | $ / shares	$ 0.01
Preferred stock, liquidation preference per share (in usd per share) | $ / shares	$ 1,000
Depositary shares issued (in shares)	5,400,000
Common stock repurchase program (in shares)

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss, Net of Tax (Schedule of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 8,056,186	$ 3,438,325	$ 3,234,625
Other comprehensive income (loss), net of tax	134,389	(662,380)	(64,836)
Ending Balance	8,689,996	8,056,186	3,438,325
Available For Sale and Transferred Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(631,160)	4,536	67,424
Other comprehensive income before reclassifications	86,391	(640,656)
Amounts reclassified from accumulated other comprehensive loss	27,319	4,960	0
Ending Balance	(517,450)	(631,160)	4,536
Derivative Instruments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(8,874)	6,070	19,918
Other comprehensive income before reclassifications	4,066	(17,810)	(17,109)
Amounts reclassified from accumulated other comprehensive loss	1,939	2,866	3,261
Ending Balance	(2,869)	(8,874)	6,070
Defined Benefit Pension and Postretirement Benefit Plans [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(44,926)	(33,186)	(45,086)
Other comprehensive income before reclassifications	11,794	(13,350)	8,876
Amounts reclassified from accumulated other comprehensive loss	2,880	1,610	3,024
Ending Balance	(30,252)	(44,926)	(33,186)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(684,960)	(22,580)	42,256
Other comprehensive income before reclassifications	102,251	(671,816)	(71,121)
Amounts reclassified from accumulated other comprehensive loss	32,138	9,436	6,285
Other comprehensive income (loss), net of tax	134,389	(662,380)	(64,836)
Ending Balance	$ (550,571)	$ (684,960)	$ (22,580)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss, Net of Tax (Schedule of Reclassifications from AOCI) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Loss on sale of investment securities	$ (33,620)	$ (6,751)	$ 0
Interest expense	(1,290,991)	(250,451)	(41,755)
Interest income	3,628,260	2,284,737	942,844
Income tax expense	(216,664)	(153,694)	(124,997)
Earnings applicable to common shareholders	843,268	622,692	398,687
Gain (Loss) on Sale of Investments	3,800	0
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Including Noncontrolling Interest [Member] | Reclassification out of accumualted comprehensive income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Loss on sale of investment securities	(37,356)	(6,751)	0
Available For Sale and Transferred Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	(27,319)	(4,960)	0
Available For Sale and Transferred Securities [Member] | Reclassification out of accumualted comprehensive income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	10,037	1,791	0
Earnings applicable to common shareholders	(27,319)	(4,960)	0
Derivative Instruments
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	(1,939)	(2,866)	(3,261)
Derivative Instruments | Reclassification out of accumualted comprehensive income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	(310)	(306)	(306)
Interest income	(2,349)	(3,626)	(4,109)
Income tax expense	720	1,066	1,154
Earnings applicable to common shareholders	(1,939)	(2,866)	(3,261)
Accumulated Defined Benefit Plans Adjustment, Net Unamortized Gain (Loss) [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(2,083)	(2,210)	(4,102)
Reclassification from Accumulated Other Comprehensive Income, Other, Current Period, before Tax	(1,869)	0	0
Defined benefit pension and postretirement benefit plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax benefit	1,072	600	1,078
Net of tax	$ (2,880)	$ (1,610)	$ (3,024)

Accumulated Other Comprehensi_5

Accumulated Other Comprehensive Loss, Net of Tax (Schedule of Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale securities:
Net unrealized loss during the period	$ 118,410	$ (878,366)	$ (85,368)
Reclassification for net gain included in net income	37,356	6,751
Total available-for-sale securities	155,766	(871,615)	(85,368)
Derivative instruments:
Net unrealized gains arising during the year	5,578	(24,440)	(23,216)
Reclassification adjustment for net realized losses included in net income	2,659	3,932	4,415
Total derivative instruments	8,237	(20,508)	(18,801)
Defined benefit pension and other postretirement benefit plans:
Net actuarial gain arising during the year	16,183	(18,319)	12,052
Reclassification adjustment for amortization of net loss included in net income	(3,952)	(2,210)	(4,102)
Total (gain) loss recognized in OCI (OCL)	(20,135)	16,109	(16,154)
Available-for-sale securities:
Net unrealized loss during the period	(32,019)	237,710	22,480
Reclassification for net gain included in net income	10,037	1,791
Total investment securities available-for-sale	42,056	(235,919)	(22,480)
Derivative instruments:
Net unrealized gains arising during the year	(1,512)	6,630	6,107
Reclassification adjustment for net realized losses included in net income	(720)	(1,066)	(1,154)
Total derivative instruments	(2,232)	5,564	4,953
Defined benefit pension and other postretirement benefit plans:
Current year actuarial loss	(4,389)	4,969	(3,176)
Reclassification adjustment for amortization of net loss included in net income	(1,072)	(600)	(1,078)
Total defined benefit pension and postretirement benefit plans	(5,461)	4,369	(4,254)
Available-for-sale securities:
Net unrealized loss during the period			(62,888)
Reclassification for net gain included in net income	27,319	4,960
Total available-for-sale securities	113,710	(635,696)	(62,888)
Derivative instruments:
Derivative instruments	6,005	(14,944)	(13,848)
Defined benefit pension and other postretirement benefit plans:
Total defined benefit pension and postretirement benefit plans	14,674	(11,740)	11,900
Other Comprehensive Income (Loss), Pre-Tax Amount	184,138	(908,232)	(88,015)
Other Comprehensive Income (Loss), Tax Benefit (Expense)	(49,749)	245,852	23,179
Other comprehensive income (loss), net of tax	$ 134,389	$ (662,380)	$ (64,836)

Regulatory Matters (Information

Regulatory Matters (Information On The Capital Ratios) (Detail) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital	$ 6,188,433	$ 5,822,369
Common Equity Tier One Capital Required for Capital Adequacy	$ 2,507,190	$ 2,446,344
Common Equity Tier One Capital Ratio	0.1111	0.1071
Common Equity Tier One Capital Required to be Well-Capitalized	$ 3,621,497	$ 3,533,608
Total risk-based capital, Actual Amount	$ 7,643,423	$ 7,203,029
Total risk-based capital, Actual Ratio	0.1372	0.1325
Total risk-based capital, Capital Requirements, Minimum Amount	$ 4,457,227	$ 4,349,056
Total risk-based capital, Capital Requirements, Minimum Ratio	0.080	0.080
Total risk-based capital, Capital Requirements, Well Capitalized Amount	$ 5,571,534	$ 5,436,320
Total risk-based capital, Capital Requirements, Well Capitalized Ratio	0.100	0.100
Tier 1 risk-based capital, Actual Amount	$ 6,472,412	$ 6,106,348
Tier 1 risk-based capital, Actual Ratio	0.1162	0.1123
Tier 1 risk-based capital, Capital Requirements, Minimum Amount	$ 3,342,920	$ 3,261,792
Tier 1 risk-based capital, Capital Requirements, Minimum Ratio	0.060	0.060
Tier 1 risk-based capital, Capital Requirements, Well Capitalized Amount	$ 4,457,227	$ 4,349,056
Tier 1 risk-based capital, Capital Requirements, Well Capitalized Ratio	0.080	0.080
Tier 1 leverage capital, Actual Amount	$ 6,472,412	$ 6,106,348
Tier 1 leverage capital, Actual Ratio	0.0906	0.0895
Tier 1 leverage capital, Capital Requirements, Minimum Amount	$ 2,857,890	$ 2,730,212
Tier 1 leverage capital, Capital Requirements, Minimum Ratio	0.040	0.040
Tier 1 leverage capital, Capital Requirements, Well Capitalized Amount	$ 3,572,362	$ 3,412,765
Tier 1 leverage capital, Capital Requirements, Well Capitalized Ratio	0.050	0.050
Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital	$ 6,913,443	$ 6,661,504
Common Equity Tier One Capital Required for Capital Adequacy	$ 2,502,835	$ 2,442,058
Common Equity Tier One Capital Ratio	0.1243	0.1228
Common Equity Tier One Capital Required to be Well-Capitalized	$ 3,615,206	$ 3,527,417
Total risk-based capital, Actual Amount	$ 7,494,332	$ 7,165,935
Total risk-based capital, Actual Ratio	0.1347	0.1320
Total risk-based capital, Capital Requirements, Minimum Amount	$ 4,449,484	$ 4,341,437
Total risk-based capital, Capital Requirements, Minimum Ratio	0.080	0.080
Total risk-based capital, Capital Requirements, Well Capitalized Amount	$ 5,561,855	$ 5,426,796
Total risk-based capital, Capital Requirements, Well Capitalized Ratio	0.100	0.100
Tier 1 risk-based capital, Actual Amount	$ 6,913,443	$ 6,661,504
Tier 1 risk-based capital, Actual Ratio	0.1243	0.1228
Tier 1 risk-based capital, Capital Requirements, Minimum Amount	$ 3,337,113	$ 3,256,078
Tier 1 risk-based capital, Capital Requirements, Minimum Ratio	0.060	0.060
Tier 1 risk-based capital, Capital Requirements, Well Capitalized Amount	$ 4,449,484	$ 4,341,437
Tier 1 risk-based capital, Capital Requirements, Well Capitalized Ratio	0.080	0.080
Tier 1 leverage capital, Actual Amount	$ 6,913,443	$ 6,661,504
Tier 1 leverage capital, Actual Ratio	0.0969	0.0977
Tier 1 leverage capital, Capital Requirements, Minimum Amount	$ 2,855,212	$ 2,727,476
Tier 1 leverage capital, Capital Requirements, Minimum Ratio	0.040	0.040
Tier 1 leverage capital, Capital Requirements, Well Capitalized Amount	$ 3,569,015	$ 3,409,345
Tier 1 leverage capital, Capital Requirements, Well Capitalized Ratio	0.050	0.050
Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital Ratio	0.045	0.045
Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets [Member] | Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital Ratio	0.045	0.045
Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital Ratio	0.065	0.065
Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets [Member] | Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital Ratio	0.065	0.065

Regulatory Matters Regulatory M

Regulatory Matters Regulatory Matters - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Cash dividends paid to parent company	$ 600	$ 475

Earnings Per Common Share (Earn

Earnings Per Common Share (Earnings Per Share Basic And Diluted) (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share Reconciliation [Abstract]
Net income	$ 867,840	$ 644,283	$ 408,864
Less: Preferred stock dividends	16,650	15,919	7,875
Net income available to common shareholders, basic	851,190	628,364	400,989
Net income available to common shareholders, diluted	851,190	628,364	400,989
Less: Earnings applicable to participating securities, basic	7,922	5,672	2,302
Less: Earnings applicable to participating securities, diluted	7,922	5,672	2,302
Earnings applicable to common shareholders	843,268	622,692	398,687
Earnings applicable to common shareholders, diluted	$ 843,268	$ 622,692	$ 398,687
Earnings per common share:
Earnings per common share, Basic (in dollars per share)	$ 4.91	$ 3.72	$ 4.43
Earnings per common share, Diluted (in dollars per share)	$ 4.91	$ 3.72	$ 4.42
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted-average common shares outstanding - basic	171,775	167,452	89,983
Stock options and restricted stock (in shares)	108	95	223
Weighted Average Number of Shares Outstanding, Diluted	171,883	167,547	90,206

Earnings Per Common Share (Sche

Earnings Per Common Share (Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share) (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restricted Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, shares	204,945	176,177	56,829

Derivative Financial Instrume_2

Derivative Financial Instruments (Schedule fair value of derivative instruments) (Detail) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	$ 11,377,707,000	$ 8,539,724,000
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	330,636,000	222,906,000
Derivative Asset, Fair Value, Amount Offset Against Collateral	55,949,000	16,129,000
Asset Derivatives, Fair Value, Less: Cash collateral posted	232,190,000	184,095,000
Derivative asset	42,497,000	22,682,000
Liability Derivatives, Notional Amount	11,703,252,000	9,379,322,000
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	335,810,000	414,499,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	55,949,000	16,129,000
Liability Derivatives, Fair Value, Less: Cash collateral posted	$ 0	$ 0
Derivative Asset Statement Of Financial Position Extensible Enumeration Not Disclosed Flag	true	true
Derivative liability	$ 279,861,000	$ 398,370,000
CME SWAPS MARKETS (CME) [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value, Less: Cash collateral posted	3,000,000
Cross Currency Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	299,200,000	125,600,000
Liability Derivatives, Notional Amount	682,900,000	559,200,000
CME
Derivatives, Fair Value [Line Items]
Derivative asset	0
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	289,778,000	217,246,000
Derivative Asset, Fair Value, Amount Offset Against Collateral	55,949,000	16,129,000
Derivative asset	232,190,000	184,095,000
Derivative Liability, Fair Value, Gross Liability	55,949,000	16,129,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	55,949,000	16,129,000
Derivative liability	0	0
Designated as Hedging Instrument [Member] | Interest rate derivatives [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	2,750,000,000	1,350,000,000
Derivative Asset, Fair Value, Gross Asset	11,140,000	1,515,000
Liability Derivatives, Notional Amount	2,700,000,000	1,750,000,000
Derivative Liability, Fair Value, Gross Liability	13,679,000	9,632,000
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	8,627,707,000	7,189,724,000
Asset Derivatives, Fair Value, Positions not subject to master netting agreement	319,496,000	221,391,000
Liability Derivatives, Notional Amount	9,003,252,000	7,629,322,000
Liability Derivatives, Fair Value, Positions not subject to master netting agreement	322,131,000	404,867,000
Not Designated as Hedging Instrument [Member] | Interest rate derivatives [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	8,284,356,000	7,024,507,000
Derivative Asset, Fair Value, Gross Asset	319,122,000	221,225,000
Liability Derivatives, Notional Amount	8,272,197,000	7,022,844,000
Derivative Liability, Fair Value, Gross Liability	321,064,000	403,952,000
Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member] | RPA-Out [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	2,798,000	3,283,000
Derivative Asset, Fair Value, Gross Asset	37,000	32,000
Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member] | RPA-In [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Notional Amount	0	0
Derivative Liability, Fair Value, Gross Liability	0	0
Not Designated as Hedging Instrument [Member] | Other Contract [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	340,553,000	161,934,000
Derivative Asset, Fair Value, Gross Asset	337,000	134,000
Liability Derivatives, Notional Amount	731,055,000	606,478,000
Derivative Liability, Fair Value, Gross Liability	1,067,000	915,000
Not Designated as Hedging Instrument [Member] | CME SWAPS MARKETS (CME) [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	100,000,000	2,700,000,000
Liability Derivatives, Notional Amount	0	0
Interest Rate Lock Commitments [Member]
Derivatives, Fair Value [Line Items]
Other Commitment	$ 1,000,000	$ 2,400,000

Derivative Financial Instrume_3

Derivative Financial Instruments (Offsetting Derivatives) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative instrument asset, Amount Offset, Total	$ (55,949)	$ (16,129)
Derivative instrument asset, Amount Offset	232,190	184,095
Derivative asset	42,497	22,682
Derivative Liability, Fair Value, Amount Offset Against Collateral	55,949	16,129
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative liability	279,861	398,370
Derivative Credit Risk Valuation Adjustment, Derivative Assets	6,200
Hedge Accounting Positions [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	289,778	217,246
Derivative instrument asset, Amount Offset, Total	(55,949)	(16,129)
Derivative asset	232,190	184,095
Derivative Liability, Fair Value, Gross Liability	55,949	16,129
Derivative Liability, Fair Value, Amount Offset Against Collateral	55,949	16,129
Derivative liability	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(1,639)	(17,022)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	0	0
Interest Rate Derivatives [Member] | Hedge Accounting Positions [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	11,140	1,515
Derivative Liability, Fair Value, Gross Liability	$ 13,679	$ 9,632

Derivative Financial Instrume_4

Derivative Financial Instruments Impact of Fair Value on Qualifying Hedges (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings				$ 28,293	$ 10,471
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)				$ 33,458
HedgedLiabilityStatementOfFinancialPositionExtensibleEnumerationNotDisclosedFlag			true	true
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			$ (14,938)	$ 1,629	10,265
Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ (3,179)	$ 0			0
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			(8,630)
Operating Expense [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(15)	0			0
Interest rate derivatives [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			(6,159)	25,092	10,369
Interest rate derivatives [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			310	306	411
Interest rate derivatives [Member] | Other Income [Member] | Not Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			(14,628)	1,935	10,676
Mortgage Banking Derivatives [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			5	(48)	(776)
Other Contract [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			(2,476)	3,249	878
Interest Expense, Deposits
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Liability, Fair Value Hedge			401,320	0
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)			1,320	0
Derivative, Notional Amount			400,000	0
Interest Expense, Other Long Term Debt
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Liability, Fair Value Hedge			328,104	333,458
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)			28,104
Derivative, Notional Amount			$ 300,000	$ 300,000
Interest Expense, Other Long Term Debt | Operating Expense [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ 3,194	$ 0			$ 0

Derivative Financial Instrume_5

Derivative Financial Instruments (Schedule of the changes in the fair value of non-hedge accounting derivatives) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings		$ 28,293	$ 10,471
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ (8,630)
Interest Rate Derivatives [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(6,159)	25,092	10,369
Mortgage Banking Derivatives [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	5	(48)	(776)
Other Contract [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(2,476)	3,249	878
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(14,938)	1,629	10,265
Cash Flow Hedging [Member] | Interest Rate Derivatives [Member] | Operating Expense [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	310	306	411
Cash Flow Hedging [Member] | Interest Rate Derivatives [Member] | Other Income [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ (14,628)	$ 1,935	$ 10,676

Derivative Financial Instrume_6

Derivative Financial Instruments (AOCI Related to Cash Flow Hedges) (Narrative) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Price Risk Derivative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Remaining unamortized gain (loss)	$ 500
Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Estimate of amount to be reclassified from AOCL	$ 21,900
Maximum Length of Time Hedged in Cash Flow Hedge	3 years 3 months 18 days

Derivative Financial Instrume_7

Derivative Financial Instruments (Counterparty Credit Risk Narrative) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative instrument asset, Amount Offset	$ 232,190	$ 184,095
Credit Derivative, Maximum Exposure, Undiscounted	40,800
Derivative Credit Risk Valuation Adjustment, Derivative Liabilities		$ 8,400
Valuation, Cost Approach [Member]
Derivative [Line Items]
Derivative, Collateral, Right to Reclaim Cash	232,700
Valuation, Market Approach [Member]
Derivative [Line Items]
Credit Derivative, Maximum Exposure, Undiscounted	109,800
CME SWAPS MARKETS (CME) [Member]
Derivative [Line Items]
Derivative instrument asset, Amount Offset	$ 3,000

Derivative Financial Instrume_8

Derivative Financial Instruments Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 55,949	$ 16,129
Derivative Asset	42,497	22,682
Derivative Liability, Fair Value, Amount Offset Against Collateral	55,949	16,129
Derivative Liability	279,861	398,370
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	55,949	16,129
Derivative Asset, Fair Value, Gross Asset	289,778	217,246
Derivative Asset, Fair Value, Amount Offset Against Collateral	55,949	16,129
Derivative Asset	232,190	184,095
Derivative Liability, Fair Value, Amount Offset Against Collateral	55,949	16,129
Derivative Liability	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	1,639	17,022
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	$ 0	$ 0

Fair Value Measurements Fair va

Fair Value Measurements Fair value Option, Disclosures (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Fair Value Disclosure	$ 2,610	$ 1,991
Unpaid Principal Balance	6,541	1,991
Difference	(48)	360
loans held for sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Unpaid Principal Balance	$ 2,658	$ 1,631

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Unobservable Inputs) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) holding
Re-sign Broker Dealers
Fair Value, Option, Quantitative Disclosures [Line Items]
Business Combination, Contingent Consideration, Liability | $	$ 4,232
Re-sign Broker Dealers | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Business Combination, Contingent Consideration, Liability | $	4,826
Deposit Program Growth
Fair Value, Option, Quantitative Disclosures [Line Items]
Business Combination, Contingent Consideration, Liability | $	11,568
Deposit Program Growth | Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Business Combination, Contingent Consideration, Liability | $	$ 12,500
Probability of Achievement | Re-sign Broker Dealers
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent Consideration, Measurement Input | holding	0.990
Probability of Achievement | Deposit Program Growth
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent Consideration, Measurement Input | holding	1
Payment Term (in years) | Re-sign Broker Dealers
Fair Value, Option, Quantitative Disclosures [Line Items]
Payment Term (in years)	1 year 10 months 17 days
Payment Term (in years) | Deposit Program Growth
Fair Value, Option, Quantitative Disclosures [Line Items]
Payment Term (in years)	1 year
Discount Rate | Re-sign Broker Dealers
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent Consideration, Measurement Input | holding	0.0640
Discount Rate | Deposit Program Growth
Fair Value, Option, Quantitative Disclosures [Line Items]
Contingent Consideration, Measurement Input | holding	0.0640

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Jan. 11, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unused Commitments to Extend Credit	$ 12,563,441		$ 11,671,663
Mortgage Loans in Process of Foreclosure, Amount	8,700
Equity Securities without Readily Determinable Fair Value, Downward Price Adjustment, Annual Amount	(1,000)
Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Annual Amount	1,800
Additional funds committed to borrowers in TDR status			1,724
Loan Transferred to Held-for-Sale, Fair Value Disclosure	3,900		0
Broker Dealer Deposit Program, Fair Value		$ 2,500,000
interLINK
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration, Liability		$ 16,000
Rabbi Trust [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Assets, Fair Value Disclosure	9,200		10,000
Alternative investments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Assets, Fair Value Disclosure	29,800		82,700
Equity Securities, FV-NI	900		400
Equity Securities without Readily Determinable Fair Value, Amount	35,900		89,200
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	500
Additional funds committed to borrowers in TDR status	0
Fair Value, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Assets, Fair Value Disclosure	9,100		2,300
Fair Value, Nonrecurring [Member] | Alternative investments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unused Commitments to Extend Credit	53,100		42,800
Alternative investments, written up	$ 7,900		$ 5,900

Fair Value Measurements (Fair_2

Fair Value Measurements (Fair Value Assets And Liabilities Measured On Recurring Basis) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	$ 42,497	$ 22,682
Loans Held-for-sale, Fair Value Disclosure	$ 2,610	1,991
Derivative Liability Statement Of Financial Position Extensible Enumeration Not Disclosed Flag	true
Derivative liability	$ 279,861	398,370
Fair Value	8,959,729	7,892,697
Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	8,959,729	7,892,697
Alternative Investment	959	430
Alternative investments measured at NAV	35,888	89,248
Assets, Fair Value Disclosure	9,341,722	8,219,375
Derivative liability	335,810	414,499
Business Combination, Contingent Consideration, Liability	15,800
Liabilities, Fair Value Disclosure	351,610
Fair Value, Recurring [Member] | Derivative instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	330,636	222,906
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	717,040
Alternative Investment	959	430
Alternative investments measured at NAV	0	0
Assets, Fair Value Disclosure	13,076	729,652
Derivative liability	970	843
Business Combination, Contingent Consideration, Liability	0
Liabilities, Fair Value Disclosure	970
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Derivative instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	217	79
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	8,959,729	7,175,657
Alternative Investment	0	0
Alternative investments measured at NAV	0	0
Assets, Fair Value Disclosure	9,292,758	7,400,475
Derivative liability	334,840	413,656
Business Combination, Contingent Consideration, Liability	0
Liabilities, Fair Value Disclosure	334,840
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	330,419	222,827
Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Alternative Investment	0	0
Alternative investments measured at NAV	0	0
Assets, Fair Value Disclosure	0	0
Derivative liability	0	0
Business Combination, Contingent Consideration, Liability	15,800
Liabilities, Fair Value Disclosure	15,800
Fair Value, Recurring [Member] | Level 3 | Derivative instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	0	0
Investments held In Rabbi Trust [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Assets, Fair Value Disclosure	11,900	12,103
Investments held In Rabbi Trust [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Assets, Fair Value Disclosure	11,900	12,103
Investments held In Rabbi Trust [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Assets, Fair Value Disclosure	0	0
Investments held In Rabbi Trust [Member] | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Assets, Fair Value Disclosure	0	0
Loan Origination Commitments [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Fair Value Disclosure	2,610	1,991
Loan Origination Commitments [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Fair Value Disclosure	0	0
Loan Origination Commitments [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Fair Value Disclosure	2,610	1,991
Loan Origination Commitments [Member] | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Held-for-sale, Fair Value Disclosure	0	0
US Treasury and Government | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		717,040
US Treasury and Government | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		717,040
US Treasury and Government | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		0
US Treasury and Government | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		0
Agency CMO
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	48,941	59,965
Agency CMO | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	48,941	59,965
Agency CMO | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Agency CMO | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	48,941	59,965
Agency CMO | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Agency MBS
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,347,098	2,158,024
Agency MBS | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	3,347,098	2,158,024
Agency MBS | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Agency MBS | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	3,347,098	2,158,024
Agency MBS | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Agency commercial mortgage-backed securities (agency CMBS) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	2,288,071	1,406,486
Agency commercial mortgage-backed securities (agency CMBS) [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	2,288,071	1,406,486
Agency commercial mortgage-backed securities (agency CMBS) [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Agency commercial mortgage-backed securities (agency CMBS) [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	2,288,071	1,406,486
Agency commercial mortgage-backed securities (agency CMBS) [Member] | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
CMBS
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	763,749	896,640
CMBS | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	763,749	896,640
CMBS | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
CMBS | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	763,749	896,640
CMBS | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
CLO
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		2,107
CLO | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		2,107
CLO | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		0
CLO | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		2,107
CLO | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value		0
Corporate debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	622,155	704,412
Corporate debt | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	622,155	704,412
Corporate debt | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Corporate debt | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	622,155	704,412
Corporate debt | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale, at fair value	0	0
Government agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	264,633	258,374
Government agency debentures | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	264,633	258,374
Government agency debentures | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Government agency debentures | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	264,633	258,374
Government agency debentures | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Municipal bonds and notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,573,233	1,633,202
Municipal bonds and notes | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,573,233	1,633,202
Municipal bonds and notes | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Municipal bonds and notes | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,573,233	1,633,202
Municipal bonds and notes | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Private label MBS
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	42,808	44,249
Private label MBS | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	42,808	44,249
Private label MBS | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Private label MBS | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	42,808	44,249
Private label MBS | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	9,041	12,198
Other | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	9,041	12,198
Other | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Other | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	9,041	12,198
Other | Fair Value, Recurring [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 0	$ 0

Fair Value Measurements (Summar

Fair Value Measurements (Summary Of Estimated Fair Values Of Significant Financial Instruments) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held to maturity securities	$ 7,074,797	$ 6,564,879
Debt Securities, Held-to-maturity, Fair Value	6,264,623	5,761,453
Mortgage servicing assets, Carrying Amount	8,523	9,515	$ 9,237	$ 13,422
Mortgage servicing assets	8,300
Reported Value Measurement [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	1,715,795	839,943
Held to maturity securities	7,074,588	6,564,697
Loans and leases, net	50,090,315	49,169,685
Securities sold under agreements to repurchase and other borrowings	458,387	1,151,830
FHLB advances	2,360,018	5,460,552
Long-term debt	1,048,820	1,073,128
Reported Value Measurement [Member] | Fair Value, Nonrecurring [Member] | Deposits other than time deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits	52,319,825	49,893,391
Reported Value Measurement [Member] | Fair Value, Nonrecurring [Member] | Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits	8,464,459	4,160,949
Reported Value Measurement [Member] | Fair Value, Nonrecurring [Member] | Residential
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing assets, Carrying Amount	8,523	9,515
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	1,715,795	839,943
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	6,264,623	5,761,453
Securities sold under agreements to repurchase and other borrowings	458,380	1,151,797
FHLB advances	2,358,381	5,459,218
Long-term debt	999,918	1,001,779
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Nonrecurring [Member] | Deposits other than time deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits	52,319,825	49,893,391
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Nonrecurring [Member] | Time Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deposits	8,426,708	4,091,979
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans and leases, net	48,048,106	47,604,463
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Nonrecurring [Member] | Residential
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing assets	$ 24,495	$ 27,043

Retirement Benefit Plans - Narr

Retirement Benefit Plans - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jul. 01, 2021
Defined Benefit Plan Disclosure [Line Items]
Expected Long-Term Rate of Return on Plan Assets	6%
Shortfall amortization period	15 years
Funded status of plan				$ 3.1
Sterling National Bank 401k And Profit Sharing Plan
Defined Benefit Plan Disclosure [Line Items]
Employee annual contribution percent of eligible compensation	50%
Employer matching contribution, percent of match	50%
Maximum employee contributions of eligible compensation	4%
Maximum match	2%
Profit sharing contribution	3%
Salary deferral contributions automatic increase	1%
Salary maximum deferral contributions automatic increase	10%
Compensation expense	$ 20.3	$ 18.2	$ 13.1
Webster Bank Retirement Savings Plan
Defined Benefit Plan Disclosure [Line Items]
Employee annual contribution percent of eligible compensation	75%
Employer matching contribution, percent of match	100%
Employer matching contribution, percent of employees' gross pay	2%
Employer matching contribution, additional percent of match	50%
Employer additional matching contribution, percent of employees' gross pay	6%
Employer additional matching contribution, percent of employees' gross pay, default	3%
Fixed Income Funds
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage	64.50%
Actual asset allocation percentages	64.20%
Equity Funds
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation percentage	35.50%
Actual asset allocation percentages	35.20%
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Actual asset allocation percentages	0.60%

Retirement Benefit Plans - Chan

Retirement Benefit Plans - Changes in Plan Assets and Funded Status of Pension Plans and Other Postretirement Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jul. 01, 2021
Change in plan assets:
Beginning balance	$ 201,382
Ending balance	217,167	$ 201,382
Funded status of the plan at year end				$ 3,100
Pension
Change in benefit obligation:
Beginning balance	187,836	250,263
Service cost	0	0	$ 0
Interest cost	8,782	5,565	4,663
Actuarial (gain) loss	3,333	(57,751)
Benefits paid	(9,965)	(10,241)
Benefit obligation assumed from Sterling	0	0
Ending balance	189,986	187,836	250,263
Change in plan assets:
Beginning balance	201,382	271,846
Actual return on plan assets	25,750	(60,223)
Employer contributions	0	0
Benefits paid	(9,965)	(10,241)
Ending balance	217,167	201,382	271,846
Funded status of the plan at year end	27,181	13,546
SERP
Change in benefit obligation:
Beginning balance	4,245	1,873
Service cost	0	0	0
Interest cost	191	107	30
Actuarial (gain) loss	183	(581)
Benefits paid	(480)	(1,671)
Benefit obligation assumed from Sterling	0	4,517
Ending balance	4,139	4,245	1,873
Change in plan assets:
Beginning balance	0	0
Actual return on plan assets	0	0
Employer contributions	480	1,671
Benefits paid	(480)	(1,671)
Ending balance	0	0	0
Funded status of the plan at year end	(4,139)	(4,245)
OPEB
Change in benefit obligation:
Beginning balance	22,822	1,904
Service cost	27	34	0
Interest cost	1,042	652	19
Actuarial (gain) loss	(382)	(4,992)
Benefits paid	(840)	(806)
Benefit obligation assumed from Sterling	0	26,030
Ending balance	22,669	22,822	1,904
Change in plan assets:
Beginning balance	0	0
Actual return on plan assets	0	0
Employer contributions	840	806
Benefits paid	(840)	(806)
Ending balance	0	0	$ 0
Funded status of the plan at year end	$ (22,669)	$ (22,822)

Retirement Benefit Plans - Weig

Retirement Benefit Plans - Weighted Average Assumptions used to Determine Benefit Obligations (Details)	Dec. 31, 2023	Dec. 31, 2022
Pension | Webster Bank Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.76%	4.96%
SERP | Webster Bank Supplemental Defined Benefit Plan for Executive Officers
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.68%	4.88%
SERP | Astoria Bank Excess Benefit and Supplemental Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.56%	4.77%
SERP | Astoria Bank Directors' Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.50%	4.70%
SERP | Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.50%	4.70%
SERP | Supplemental Executive Retirement Plan of Provident Bank
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.83%	5.04%
SERP | Supplemental Executive Retirement Plan of Provident Bank - Other
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.71%	4.90%
OPEB | Webster Bank Postretirement Medical Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.54%	4.72%
OPEB | Sterling Bancorp Supplemental Postretirement Life Insurance Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.51%	4.70%
OPEB | Astoria Bank Postretirement Welfare Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.74%	4.94%
OPEB | Split Dollar Life Insurance Arrangement
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.45%	4.63%

Retirement Benefit Plans - Summ

Retirement Benefit Plans - Summary of Components of Accumulated Other Comprehensive Loss Related to Pensions and Postretirement Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Pension
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	$ 41,296	$ 56,717
Deferred tax (benefit) expense	(11,201)	(15,383)
Net amount recorded in (AOCL)	30,095	41,334
SERP
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	312	50
Deferred tax (benefit) expense	(85)	(14)
Net amount recorded in (AOCL)	227	36
OPEB
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss (gain)	(3,231)	(5,573)
Deferred tax (benefit) expense	876	1,512
Net amount recorded in (AOCL)	$ (2,355)	$ (4,061)

Retirement Benefit Plans - Su_2

Retirement Benefit Plans - Summary of Net Periodic Benefit Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 0
Interest cost	8,782	5,565	4,663
Expected return on plan assets	(11,778)	(14,675)	(14,385)
Amortization of actuarial loss (gain)	4,781	2,224	4,102
Net periodic benefit cost (benefit)	1,785	(6,886)	(5,620)
SERP
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0
Interest cost	191	107	30
Expected return on plan assets	0	0	0
Amortization of actuarial loss (gain)	6	26	38
Net periodic benefit cost (benefit)	197	133	68
OPEB
Defined Benefit Plan Disclosure [Line Items]
Service cost	27	34	0
Interest cost	1,042	652	19
Expected return on plan assets	0	0	0
Amortization of actuarial loss (gain)	(2,704)	(40)	(38)
Net periodic benefit cost (benefit)	$ (1,635)	$ 646	$ (19)

Retirement Benefit Plans - We_2

Retirement Benefit Plans - Weighted Average Assumptions used to Determine Net Periodic Benefit Cost (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2033	Dec. 31, 2030
Defined Benefit Plan Disclosure [Line Items]
Expected Long-Term Rate of Return on Plan Assets	6%
Forecast
Defined Benefit Plan Disclosure [Line Items]
Cost trend rate				4.50%	4.40%
Pension | Webster Bank Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.96%	2.65%	2.29%
Expected Long-Term Rate of Return on Plan Assets	6%	5.50%	5.50%
SERP | Webster Bank Supplemental Defined Benefit Plan for Executive Officers
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.88%	2.45%	1.91%
SERP | Astoria Bank Excess Benefit and Supplemental Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.77%	2.58%
SERP | Astoria Bank Directors' Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.70%	2.23%
SERP | Retirement Plan of the Greater New York Savings Bank for Non-Employee Directors
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.70%	2.37%
SERP | Supplemental Executive Retirement Plan of Provident Bank
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	5.04%	2.76%
SERP | Supplemental Executive Retirement Plan of Provident Bank - Other
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.90%	2.38%
OPEB | Webster Bank Postretirement Medical Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.72%	1.99%	1.40%
Assumed Healthcare Cost Trend Rate	6.50%	6.25%	6.50%
OPEB | Sterling Bancorp Supplemental Postretirement Life Insurance Plan
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.70%	2.35%
OPEB | Astoria Bank Postretirement Welfare Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.94%	2.93%
Assumed Healthcare Cost Trend Rate	6.40%	6.60%
OPEB | Split Dollar Life Insurance Arrangement
Defined Benefit Plan Disclosure [Line Items]
Discount Rate	4.63%	2.20%

Retirement Benefit Plans - Ch_2

Retirement Benefit Plans - Changes in Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net actuarial (gain) loss	$ (16,183)	$ 18,319	$ (12,052)
Amounts reclassified from (AOCL)	3,952	2,210	4,102
Total (gain) loss recognized in OCI (OCL)	(20,135)	16,109	(16,154)
Pension
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net actuarial (gain) loss	(10,639)	17,148	(12,008)
Amounts reclassified from (AOCL)	(4,781)	(2,224)	(4,102)
Total (gain) loss recognized in OCI (OCL)	(15,420)	14,924	(16,110)
SERP
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net actuarial (gain) loss	183	(581)	(77)
Amounts reclassified from (AOCL)	(6)	(26)	(38)
Total (gain) loss recognized in OCI (OCL)	177	(607)	(115)
OPEB
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net actuarial (gain) loss	(382)	(4,992)	33
Amounts reclassified from (AOCL)	2,704	40	38
Total (gain) loss recognized in OCI (OCL)	$ 2,322	$ (4,952)	$ 71

Retirement Benefit Plans - Expe

Retirement Benefit Plans - Expected Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Pension
Defined Benefit Plan Disclosure [Line Items]
2024	$ 10,634
2025	11,038
2026	11,429
2027	11,864
2028	12,246
Thereafter	64,148
SERP
Defined Benefit Plan Disclosure [Line Items]
2024	489
2025	473
2026	455
2027	433
2028	409
Thereafter	1,646
OPEB
Defined Benefit Plan Disclosure [Line Items]
2024	2,926
2025	2,789
2026	2,552
2027	2,339
2028	2,083
Thereafter	$ 7,393

Retirement Benefit Plans - Su_3

Retirement Benefit Plans - Summary of Fair Value of Plan Assets by Level (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	$ 217,167	$ 201,382
Level 1
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	22,163	28,441
Level 2
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	195,004	172,941
Level 3
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Common collective trusts
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	195,004	172,941
Common collective trusts | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Common collective trusts | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	195,004	172,941
Common collective trusts | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Registered investment companies
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	20,965	26,923
Registered investment companies | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	20,965	26,923
Registered investment companies | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Registered investment companies | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,198	1,518
Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	1,198	1,518
Cash and cash equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	0	0
Cash and cash equivalents | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total pension plan assets	$ 0	$ 0

Retirement Benefit Plans - Cont

Retirement Benefit Plans - Contributions and Funding Status of the Fund (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Contributions by Webster Bank	$ 448	$ 448	$ 692
Multiemployer Plan, Pension, Significant, Funded Status [Fixed List]	At least 80 percent	At least 80 percent

Share-Based Plans - Narrative (

Share-Based Plans - Narrative (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	21,400,000
Number of common shares available for grant	4,500,000
Unrecognized stock compensation expense	$ 40,000
Unrecognized stock compensation expense, recognition period (in years)	1 year 8 months 12 days
Award vesting percentage	50%
Fair value of restricted stock awards	$ 39,900	$ 51,700	$ 12,500
Stock options granted	605,684
Aggregate intrinsic value	$ 200
Total intrinsic value of options exercised	2,200	1,000	9,000
Exercise of stock options	$ 1,800	$ 700	$ 7,100
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights granted	937,735
Restricted Stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares available for grant	300,000
Performance-Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights granted	286,161
Performance-Based | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	0%
Performance-Based | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	150%
Stock Options Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted	0
Number of options outstanding (in shares)	10,972	88,229
Non-Qualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)	694
Incentive Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life (in years)	ten
Number of options outstanding (in shares)	10,278

Share-Based Plans - Summary of

Share-Based Plans - Summary of Restricted Stock and Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Jan. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options, Granted (in shares)		605,684
Options, Exercised (in shares)		(75,848)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Award vesting percentage		50%
Increase in stock compensation expense		$ 22.8	$ 18.8
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options, Granted (in shares)		0
Options, Exercised (in shares)		0
Sterling
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Shares issued (in shares)	87,965,239
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock, Outstanding at beginning of period (in shares)		1,479,742
Restricted Stock, Granted (in shares)		937,735
Restricted stock, Vested restricted stock awards (in shares)		(740,748)
Restricted stock, Forfeited (in shares)		(77,310)
Restricted stock, Outstanding at end of period (in shares)		1,599,419	1,479,742
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted stock, at beginning of period, Weighted-average Grant Date Fair Value (in dollars per share)		$ 50.47
Restricted stock, Granted (in dollars per share)		51.35
Restricted stock, Vested restricted stock awards (in dollars per share)		48.88
Restricted stock, Forfeited (in dollars per share)		51.62
Restricted stock, at end of period, Weighted-average Grant Date Fair Value (in dollars per share)		$ 52.72	$ 50.47
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options, Exercised (in shares)		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Options, Exercised (in dollars per share)		$ 0
Performance-Based
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock, Outstanding at beginning of period (in shares)		310,374
Restricted Stock, Granted (in shares)		286,161
Restricted stock, Vested restricted stock awards (in shares)		(60,988)
Restricted stock, Forfeited (in shares)		(15,544)
Restricted stock, Outstanding at end of period (in shares)		520,003	310,374
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted stock, at beginning of period, Weighted-average Grant Date Fair Value (in dollars per share)		$ 57.65
Restricted stock, Granted (in dollars per share)		48.86
Restricted stock, Vested restricted stock awards (in dollars per share)		60.24
Restricted stock, Forfeited (in dollars per share)		55.54
Restricted stock, at end of period, Weighted-average Grant Date Fair Value (in dollars per share)		$ 52.58	$ 57.65
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options, Exercised (in shares)		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Options, Exercised (in dollars per share)		$ 0
Performance-Based | Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Award vesting percentage		0%
Performance-Based | Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Award vesting percentage		150%
Stock Options Outstanding
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, at beginning of period, Number of Shares		88,229
Options, Granted (in shares)		0
Options, Vested (in shares)		0
Options, Forfeited (in shares)		0
Options, Exercised (in shares)		(77,257)
Options outstanding, at end of period, Number of Shares		10,972	88,229
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Options, at beginning of period, Weighted-average Exercise Price (in dollars per share)		$ 23.76
Options, Granted (in dollars per share)		0
Options, Vested (in dollars per share)		0
Options, Forfeited (in dollars per share)		0
Options, Exercised (in dollars per share)		23
Options, at end of period, Weighted-average Exercise Price (in dollars per share)		$ 29.14	$ 23.76

Share-Based Plans - Summary o_2

Share-Based Plans - Summary of Stock-based Compensation Expense Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	$ 13,900	$ 12,000	$ 5,400
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 54,500	$ 55,100	$ 13,700

Share-Based Plans - Options Out

Share-Based Plans - Options Outstanding and Options Exercisable (Details)	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Options Outstanding, Weighted-Average Remaining Contractual Life (years)	1 year 1 month 6 days
Options Exercisable, Weighted-Average Remaining Contractual Life (years)	1 year 1 month 6 days

Segment Reporting (Operating Re

Segment Reporting (Operating Results and Total Assets Reportable Segments) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Total assets	$ 74,945,249	$ 71,277,521
Net interest income (expense)	2,337,269	2,034,286	$ 901,089
Noninterest Income	314,337	440,783	323,372
Non-interest expense	1,416,355	1,396,473	745,100
Pre-tax, pre-provision net revenue	1,235,251	1,078,596	479,361
Provision (benefit) for credit losses	150,747	280,619	(54,500)
Income (loss) before income tax expense	1,084,504	797,977	533,861
Income tax expense	216,664	153,694	124,997
Net income	867,840	644,283	408,864
Goodwill	2,631,465	2,514,104	538,373
Operating Segments [Member] | Commercial Banking [Member]
Segment Reporting Information [Line Items]
Total assets	43,381,361	44,380,582
Net interest income (expense)	1,537,031	1,346,384	585,297
Noninterest Income	132,660	171,437	83,538
Non-interest expense	439,290	398,100	192,977
Pre-tax, pre-provision net revenue	1,230,401	1,119,721	475,858
Provision (benefit) for credit losses	131,237	276,550	(51,348)
Income (loss) before income tax expense	1,099,164	843,171	527,206
Income tax expense	246,212	207,188	134,965
Net income	852,952	635,983	392,241
Goodwill	2,029,204	1,904,291
Operating Segments [Member] | HSA Bank [Member]
Segment Reporting Information [Line Items]
Total assets	122,421	122,729
Net interest income (expense)	302,856	218,149	168,595
Noninterest Income	88,113	104,586	102,814
Non-interest expense	168,160	151,329	134,258
Pre-tax, pre-provision net revenue	222,809	171,406	137,151
Provision (benefit) for credit losses	0	0	0
Income (loss) before income tax expense	222,809	171,406	137,151
Income tax expense	58,822	45,937	36,619
Net income	163,987	125,469	100,532
Goodwill	57,485	57,779
Operating Segments [Member] | Community Banking [Member]
Segment Reporting Information [Line Items]
Total assets	10,789,339	10,625,334
Net interest income (expense)	798,483	720,789	375,318
Noninterest Income	107,456	119,691	95,887
Non-interest expense	425,281	426,133	297,217
Pre-tax, pre-provision net revenue	480,658	414,347	173,988
Provision (benefit) for credit losses	11,972	(3,754)	(3,068)
Income (loss) before income tax expense	468,686	418,101	177,056
Income tax expense	118,108	108,657	42,139
Net income	350,578	309,444	134,917
Goodwill	544,776	552,034
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Total assets	20,652,128	16,148,876
Net interest income (expense)	(301,101)	(251,036)	(228,121)
Noninterest Income	(13,892)	45,069	41,133
Non-interest expense	383,624	420,911	120,648
Pre-tax, pre-provision net revenue	(698,617)	(626,878)	(307,636)
Provision (benefit) for credit losses	7,538	7,823	(84)
Income (loss) before income tax expense	(706,155)	(634,701)	(307,552)
Income tax expense	(206,478)	(208,088)	(88,726)
Net income	(499,677)	(426,613)	$ (218,826)
Goodwill	$ 0	$ 0

Segment Reporting Segment Repor

Segment Reporting Segment Reporting Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Segment	Dec. 31, 2022 USD ($)	Jan. 31, 2022 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | Segment	3
Goodwill	$ 2,631,465	$ 2,514,104			$ 538,373
Deposits	60,784,284	54,054,340
Sterling
Segment Reporting Information [Line Items]
Goodwill			$ 1,914,204
Commercial Banking [Member] | Sterling
Segment Reporting Information [Line Items]
Goodwill			1,700,000
Community Banking [Member] | Sterling
Segment Reporting Information [Line Items]
Goodwill			$ 200,000
HSA Bank [Member] | Bend
Segment Reporting Information [Line Items]
Goodwill				$ 35,700
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Goodwill	$ 0	$ 0

Revenue from contracts with C_3

Revenue from contracts with Customers Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2024
Revenue from Contract with Customer, Excluding Assessed Tax	$ 233,404	$ 268,672	$ 212,406
Noninterest Income	314,337	440,783	323,372
Forecast
Estimated Special Assessment Charge				$ 47,200
Deposit Service Fees [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	169,318	198,472	162,710
Investment Advisory, Management and Administrative Service [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	28,999	40,277	39,586
Other Non Interest Income [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	17,454	8,425	10,110
Non-Interest Income Within the Scope of Other GAAP Topics [Member]
Noninterest Income	80,933	172,111	110,966
Loans and Lease Related Fees
Revenue from Contract with Customer, Excluding Assessed Tax	17,633
Operating Segments [Member] | Commercial Banking [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	49,703	60,511	29,085
Noninterest Income	132,660	171,437	83,538
Operating Segments [Member] | Commercial Banking [Member] | Deposit Service Fees [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	20,527	27,663	16,933
Operating Segments [Member] | Commercial Banking [Member] | Investment Advisory, Management and Administrative Service [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	11,543	11,350	12,152
Operating Segments [Member] | Commercial Banking [Member] | Other Non Interest Income [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0
Operating Segments [Member] | Commercial Banking [Member] | Non-Interest Income Within the Scope of Other GAAP Topics [Member]
Noninterest Income	82,957	110,926	54,453
Operating Segments [Member] | Commercial Banking [Member] | Loans and Lease Related Fees
Revenue from Contract with Customer, Excluding Assessed Tax	17,633
Operating Segments [Member] | Community Banking [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	90,676	101,803	80,172
Noninterest Income	107,456	119,691	95,887
Operating Segments [Member] | Community Banking [Member] | Deposit Service Fees [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	66,999	71,353	50,561
Operating Segments [Member] | Community Banking [Member] | Investment Advisory, Management and Administrative Service [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	17,478	28,957	27,471
Operating Segments [Member] | Community Banking [Member] | Other Non Interest Income [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	6,199	1,493	2,140
Operating Segments [Member] | Community Banking [Member] | Non-Interest Income Within the Scope of Other GAAP Topics [Member]
Noninterest Income	16,780	17,888	15,715
Operating Segments [Member] | Community Banking [Member] | Loans and Lease Related Fees
Revenue from Contract with Customer, Excluding Assessed Tax	0
Operating Segments [Member] | HSA Bank [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	88,113	104,586	102,814
Noninterest Income	88,113	104,586	102,814
Operating Segments [Member] | HSA Bank [Member] | Deposit Service Fees [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	81,051	97,654	94,844
Operating Segments [Member] | HSA Bank [Member] | Investment Advisory, Management and Administrative Service [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0
Operating Segments [Member] | HSA Bank [Member] | Other Non Interest Income [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	7,062	6,932	7,970
Operating Segments [Member] | HSA Bank [Member] | Non-Interest Income Within the Scope of Other GAAP Topics [Member]
Noninterest Income	0	0	0
Operating Segments [Member] | HSA Bank [Member] | Loans and Lease Related Fees
Revenue from Contract with Customer, Excluding Assessed Tax	0
Corporate, Non-Segment [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	4,912	1,772	335
Noninterest Income	(13,892)	45,069	41,133
Corporate, Non-Segment [Member] | Deposit Service Fees [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	741	1,802	372
Corporate, Non-Segment [Member] | Investment Advisory, Management and Administrative Service [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	(22)	(30)	(37)
Corporate, Non-Segment [Member] | Other Non Interest Income [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	4,193	0	0
Corporate, Non-Segment [Member] | Non-Interest Income Within the Scope of Other GAAP Topics [Member]
Noninterest Income	(18,804)	$ 43,297	$ 40,798
Corporate, Non-Segment [Member] | Loans and Lease Related Fees
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0

Commitments and Contingencies_2

Commitments and Contingencies (Outstanding Financial Instruments Contract Amounts Represent Credit Risk) (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	$ 12,563,441	$ 11,671,663
Standby letters of credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	482,462	380,655
Letter of Credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	54,382	53,512
Commitments to extend credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	$ 12,026,597	$ 11,237,496

Commitments and Contingencies_3

Commitments and Contingencies (Schedule for Unfunded Commitments) (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023	Nov. 29, 2023	Dec. 31, 2022
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Unused Commitments to Extend Credit		$ 12,563,441		$ 11,671,663
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Deposit Liability, Uninsured, Proposed Annual Rate			0.0336%
Forecast
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Estimated Special Assessment Charge	$ 47,200

Parent Company Information - Co

Parent Company Information - Components of Condensed Balance Sheets The Parent Company (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets:
Cash and due from banks	$ 429,323	$ 264,118
Other assets	1,890,088	1,618,175
Total assets	74,945,249	71,277,521
Liabilities and stockholders’ equity:
Total liabilities	66,255,253	63,221,335
Total liabilities and stockholders' equity	74,945,249	71,277,521
Related Party
Assets:
Intercompany debt securities		150,000
Parent Company
Assets:
Cash and due from banks	406,754	305,331
Investment in subsidiaries	9,131,026	8,631,202
Alternative investments	59,015	46,349
Other assets	13,314	13,358
Total assets	9,760,109	9,146,240
Liabilities and stockholders’ equity:
Senior notes	458,698	480,878
Subordinated notes	512,802	514,930
Junior subordinated debt	77,320	77,320
Accrued interest payable	12,693	7,457
Other liabilities	8,123	5,611
Total liabilities	1,070,113	1,090,054
Stockholders’ equity	8,689,996	8,056,186
Total liabilities and stockholders' equity	9,760,109	9,146,240
Parent Company | Related Party
Assets:
Intercompany debt securities	150,000
Parent Company | Subsidiaries [Member]
Liabilities and stockholders’ equity:
Other liabilities	$ 477	$ 3,858

Parent Company Information - _2

Parent Company Information - Components of Condensed Income Statement The Parent Company (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income:
Total income	$ 1,235,251	$ 1,078,596	$ 479,361
Expense:
Other non-interest expense	168,748	180,088	77,341
Income before income taxes and equity in undistributed earnings of subsidiaries	1,084,504	797,977	533,861
Income tax benefit	(216,664)	(153,694)	(124,997)
Net income	867,840	644,283	408,864
Parent Company
Income:
Dividend income from bank subsidiary	600,000	475,000	200,000
Interest income on securities and interest-bearing deposits	11,259	5,955	3,444
Alternative investments income	1,272	6,416	13,033
Other non-interest income	908	112	75
Total income	613,439	487,483	216,552
Expense:
Interest expense on borrowings	37,933	34,284	16,876
Merger-related expenses	2,111	40,314	16,266
Other non-interest expense	31,600	22,592	15,921
Total expense	71,644	97,190	49,063
Income before income taxes and equity in undistributed earnings of subsidiaries	541,795	390,293	167,489
Income tax benefit	15,106	20,799	3,121
Equity in undistributed earnings of subsidiaries	310,939	233,191	238,254
Net income	$ 867,840	$ 644,283	$ 408,864

Parent Company Information - _3

Parent Company Information - Components of Condensed Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other comprehensive income (loss), net of tax:
Derivative instruments	$ 6,005	$ (14,944)	$ (13,848)
Other comprehensive income (loss), net of tax	134,389	(662,380)	(64,836)
Parent Company
Condensed Statement of Income Captions [Line Items]
Net income	867,840	644,283	408,864
Other comprehensive income (loss), net of tax:
Derivative instruments	229	226	226
Other comprehensive income (loss) of subsidiaries	134,160	(662,606)	(65,062)
Other comprehensive income (loss), net of tax	134,389	(662,380)	(64,836)
Comprehensive income (loss)	$ 1,002,229	$ (18,097)	$ 344,028

Parent Company Information - _4

Parent Company Information - Components of Condensed Cash Flow The Parent Company (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities:
Net income	$ 867,840	$ 644,283	$ 408,864
Adjustments to reconcile net income to net cash provided by operating activities:
Common stock contribution to charitable foundation	0	10,500	0
Net cash provided by operating activities	978,649	1,335,952	688,592
Investing activities:
Alternative investments (capital call), net of distributions	(27,430)	(24,887)	(11,361)
Net cash (used in) provided by investing activities	(2,595,752)	(7,186,338)	(2,405,089)
Financing activities:
Dividends paid to common stockholders	(278,155)	(247,767)	(144,807)
Dividends paid to preferred stockholders	(16,650)	(13,725)	(7,875)
Exercise of stock options	1,723	703	3,492
Common stock repurchase program	(107,984)	(322,103)	0
Common shares acquired related to stock compensation plan activity	16,278	23,655	4,384
Net cash (used in) financing activities	2,492,955	6,228,759	1,914,963
Net increase (decrease) in cash and cash equivalents	875,852	378,373	198,466
Cash and cash equivalents, beginning of period	839,943	461,570	263,104
Cash and cash equivalents, at end of period	1,715,795	839,943	461,570
Parent Company
Operating activities:
Net income	867,840	644,283	408,864
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of subsidiaries	(310,939)	(233,191)	(238,254)
Common stock contribution to charitable foundation	0	10,500	0
Other, net	(8,312)	(2,853)	3,562
Net cash provided by operating activities	548,589	418,739	174,172
Investing activities:
Alternative investments (capital call), net of distributions	(13,070)	(16,292)	(6,304)
Net cash received in business combination	0	193,238	0
Net cash (used in) provided by investing activities	(13,070)	176,946	(6,304)
Financing activities:
Repayment of long-term debt	(16,752)	0	0
Dividends paid to common stockholders	278,155	247,767	145,223
Dividends paid to preferred stockholders	16,650	13,725	7,875
Exercise of stock options	1,723	703	3,492
Common stock repurchase program	107,984	322,103	0
Common shares acquired related to stock compensation plan activity	(16,278)	(23,655)	(4,384)
Net cash (used in) financing activities	(434,096)	(606,547)	(153,990)
Net increase (decrease) in cash and cash equivalents	101,423	(10,862)	13,878
Cash and cash equivalents, beginning of period	305,331	316,193	302,315
Cash and cash equivalents, at end of period	$ 406,754	$ 305,331	$ 316,193

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Thousands				2 Months Ended	3 Months Ended	12 Months Ended
	Feb. 15, 2024	Feb. 12, 2024	Jan. 24, 2024	Feb. 27, 2024	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Subsequent Event [Line Items]
Cash proceeds from sale of business					$ 4,100
Proceeds from sales of available-for-sale securities						$ 789,603	$ 172,947	$ 0
Equity Securities, FV-NI, Realized Loss						37,400	6,800
Proceeds from sales of available-for-sale securities						789,603	172,947	$ 0
Equity Securities, FV-NI, Realized Loss						$ 37,400	$ 6,800
Senior Notes | Debt Instrument, Redemption, Period One
Subsequent Event [Line Items]
Debt instrument, stated interest rate, percentage					4.375%	4.375%
Subsequent Event
Subsequent Event [Line Items]
Disposal Group Not Discontinued Operation Gain Loss On Disposal Statement Of Income Extensible List Not Disclosed Flag		true
Proceeds from sales of available-for-sale securities				$ 281,300
Equity Securities, FV-NI, Realized Loss				11,300
Proceeds from sales of available-for-sale securities				281,300
Equity Securities, FV-NI, Realized Loss				$ 11,300
Subsequent Event | Senior Notes | Debt Instrument, Redemption, Period One
Subsequent Event [Line Items]
Repayment of long-term debt	$ 132,600
Subsequent Event | Disposal Group, Disposed of by Sale, Not Discontinued Operations | Mortgage Servicing Portfolio
Subsequent Event [Line Items]
Cash proceeds from sale of business		$ 18,600
Gain recognized on sale		$ 11,900
Ametros | Subsequent Event
Subsequent Event [Line Items]
Cash consideration			$ 350,000

Uncategorized Items - wbs-20231

Label	Element	Value
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	us-gaap_ValuationAllowancesAndReservesBalance	$ 24,700,000
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	us-gaap_ValuationAllowancesAndReservesBalance	$ 27,700,000