Webster Financial (WBS) 10-Q 4 Nov 20 2020 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2020	Oct. 30, 2020
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
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	145 Bank Street
Entity Address, City or Town	Waterbury
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06702
City Area Code	203
Local Phone Number	578-2202
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 Common Stock, Shares Outstanding		90,201,149
Entity Central Index Key	0000801337
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Amendment Flag	false
Document Fiscal Period Focus	Q3
Common Class A [Member]
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	WBS
Security Exchange Name	NYSE
Series F Preferred Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	Depository Shares, each representing 1/1000th interest in a share
Trading Symbol	WBS PrF
Security Exchange Name	NYSE

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets [Abstract]
Cash and due from banks	$ 181,524	$ 185,341
Interest-bearing deposits	60,276	72,554
Investment securities available-for-sale, at fair value	3,304,217	2,925,833
Investment securities held-to-maturity, net	5,723,434	5,293,918
Allowance for credit losses on investment securities held-to-maturity	(306)	0
Investment securities held-to-maturity, net	5,723,128	5,293,918
Federal Home Loan Bank and Federal Reserve Bank stock	89,611	149,046
Loans held for sale (valued under fair value option $29,018 and $35,750)	29,018	36,053
Loans and leases	21,852,023	20,036,986
Allowance for credit losses on loans and leases	(369,811)	(209,096)
Loans and leases, net	21,482,212	19,827,890
Deferred tax assets, net	76,695	61,975
Premises and equipment, net	250,535	270,413
Goodwill	538,373	538,373
Other intangible assets, net	23,529	21,917
Cash surrender value of life insurance policies	561,021	550,651
Accrued interest receivable and other assets	674,304	455,380
Total assets	32,994,443	30,389,344
Liabilities and Equity [Abstract]
Non-interest-bearing	6,136,814	4,446,463
Interest-bearing	20,783,739	18,878,283
Total deposits	26,920,553	23,324,746
Securities sold under agreements to repurchase and other borrowings	1,301,822	1,040,431
Federal Home Loan Bank advances	433,243	1,948,476
Long-term debt	568,846	540,364
Operating lease liabilities	165,211	174,396
Accrued expenses and other liabilities	385,078	153,161
Total liabilities	29,774,753	27,181,574
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock	145,037	145,037
Common stock	937	937
Paid-in capital	1,106,473	1,113,250
Retained earnings	2,055,620	2,061,352
Treasury stock, at cost (3,482,493 and 1,659,749 shares)	(140,414)	(76,734)
Accumulated other comprehensive income (loss), net of tax	52,037	(36,072)
Total shareholders' equity	3,219,690	3,207,770
Total liabilities and shareholders' equity	$ 32,994,443	$ 30,389,344

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	3,000,000	3,000,000
Series F issued and outstanding (6,000 shares)	6,000	6,000
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Issued (93,686,311 shares)	93,686,311	93,686,311
Treasury stock, at cost (3,482,493 and 1,659,749 shares)	3,482,493	1,659,749

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest and Dividend Income, Operating [Abstract]
Interest and fees on loans and leases	$ 188,001	$ 236,453	$ 600,709	$ 701,166
Taxable interest and dividends on investments	45,549	52,046	148,240	154,556
Non-taxable interest on investment securities	5,460	5,471	16,447	16,402
Loans held for sale	229	166	588	459
Total interest income	239,239	294,136	765,984	872,583
Interest Expense [Abstract]
Deposits	12,598	34,214	59,246	97,991
Securities sold under agreements to repurchase and other borrowings	608	6,571	5,318	13,227
Federal Home Loan Bank advances	2,528	6,910	13,145	22,467
Long-term debt	4,249	5,902	13,811	15,021
Total interest expense	19,983	53,597	91,520	148,706
Net interest income	219,256	240,539	674,464	723,877
Provision for credit losses	22,750	11,300	138,750	31,800
Net interest income after provision for credit losses	196,506	229,239	535,714	692,077
Noninterest Income [Abstract]
Deposit service fees	39,278	41,410	117,687	127,552
Loan and lease related fees	6,568	8,246	20,032	22,623
Wealth and investment services	8,255	8,496	24,096	24,456
Mortgage banking activities	7,087	2,133	14,185	3,829
Increase in cash surrender value of life insurance policies	3,695	3,708	10,899	10,942
Gain on Sale of Investments	0	0	8	0
Other income	10,177	5,938	21,607	24,994
Total non-interest income	75,060	69,931	208,514	214,396
Noninterest Expense [Abstract]
Compensation and benefits	104,019	98,623	305,637	294,935
Occupancy	14,275	14,087	43,005	42,802
Technology and equipment	27,846	26,180	83,151	77,644
Intangible assets amortization	1,089	961	3,013	2,885
Marketing	3,852	4,758	10,640	12,329
Professional and outside services	9,223	5,024	21,044	16,706
Deposit insurance	4,204	4,409	13,944	13,292
Other expense	19,488	25,852	58,982	75,627
Total non-interest expense	183,996	179,894	539,416	536,220
Income before income tax expense	87,570	119,276	204,812	370,253
Income tax expense	18,289	25,411	44,235	78,003
Net income	69,281	93,865	160,577	292,250
Preferred stock dividends and other	(2,391)	(2,423)	(6,819)	(7,331)
Earnings applicable to common shareholders	$ 66,890	$ 91,442	$ 153,758	$ 284,919
Earnings Per Share, Basic and Diluted [Abstract]
Basic	$ 0.75	$ 1	$ 1.71	$ 3.11
Diluted	$ 0.75	$ 1	$ 1.70	$ 3.10

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 69,281	$ 93,865	$ 160,577	$ 292,250
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Investment securities available-for-sale	11,766	24,304	57,991	86,272
Derivative instruments	(1,912)	3,603	27,921	3,985
Defined benefit pension and other postretirement benefit plans	738	1,049	2,197	3,161
Other comprehensive income, net of tax	10,592	28,956	88,109	93,418
Comprehensive Income (Loss), Net of Tax, Attributable to Parent, Total	$ 79,873	$ 122,821	$ 248,686	$ 385,668

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Series F Preferred Stock [Member]	Preferred Stock	Preferred StockCumulative Effect, Period of Adoption, Adjustment	Common Stock	Common StockCumulative Effect, Period of Adoption, Adjustment	Paid-In Capital	Paid-In CapitalCumulative Effect, Period of Adoption, Adjustment	Retained Earnings	Retained EarningsCumulative Effect, Period of Adoption, Adjustment	Retained EarningsSeries F Preferred Stock [Member]	Treasury Stock, at cost	Treasury Stock, at costCumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income, Net of Tax	Accumulated Other Comprehensive Income, Net of TaxCumulative Effect, Period of Adoption, Adjustment
Beginning Balance at Dec. 31, 2018	$ 2,886,515	$ (515)		$ 145,037	$ 0	$ 937	$ 0	$ 1,114,394	$ 0	$ 1,828,303	$ (515)		$ (71,504)	$ 0	$ (130,652)	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	292,250									292,250
Other Comprehensive Income (Loss), Net of Tax	93,418														93,418
Dividends and dividend equivalents declared on common stock	(104,381)									(104,381)
Dividends on preferred stock			$ (5,906)									$ (5,906)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	9,684							2,839		1,179			5,666
Stock Issued During Period, Value, Stock Options Exercised	621							(2,029)					2,650
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(6,289)												(6,289)
Stock Repurchased During Period, Value	(13,003)												(13,003)
Ending Balance at Sep. 30, 2019	$ 3,152,394			145,037		937		1,115,204		2,010,930			(82,480)		(37,234)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 1.13
Dividends on preferred stock (in dollars per share)			$ 984.375
Beginning Balance at Jun. 30, 2019	$ 3,065,217	0		145,037	0	937	0	1,113,893	0	1,955,933	0		(84,393)	0	(66,190)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	93,865									93,865
Other Comprehensive Income (Loss), Net of Tax	28,956														28,956
Dividends and dividend equivalents declared on common stock	(36,900)									(36,900)
Dividends on preferred stock			$ (1,968)									(1,968)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	3,268							1,311		0			1,957
Stock Issued During Period, Value, Stock Options Exercised	0							0					0
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(44)												(44)
Stock Repurchased During Period, Value	0												0
Ending Balance at Sep. 30, 2019	$ 3,152,394			145,037		937		1,115,204		2,010,930			(82,480)		(37,234)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.40
Dividends on preferred stock (in dollars per share)			$ 328.125
Beginning Balance at Dec. 31, 2019	$ 3,207,770	(51,213)		145,037	0	937	0	1,113,250	0	2,061,352	(51,213)		(76,734)	0	(36,072)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	160,577									160,577
Other Comprehensive Income (Loss), Net of Tax	88,109														88,109
Dividends and dividend equivalents declared on common stock	(109,190)									(109,190)
Dividends on preferred stock			$ (5,906)									(5,906)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	9,356							(6,672)		0			16,028
Stock Issued During Period, Value, Stock Options Exercised	118							(105)					223
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(3,375)												(3,375)
Stock Repurchased During Period, Value	(76,556)												(76,556)
Ending Balance at Sep. 30, 2020	$ 3,219,690			145,037		937		1,106,473		2,055,620			(140,414)		52,037
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 1.20
Dividends on preferred stock (in dollars per share)			$ 984.375
Beginning Balance at Jun. 30, 2020	$ 3,174,779	$ 0		145,037	$ 0	937	$ 0	1,103,756	$ 0	2,024,487	$ 0		(140,883)	$ 0	41,445	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	69,281									69,281
Other Comprehensive Income (Loss), Net of Tax	10,592														10,592
Dividends and dividend equivalents declared on common stock	(36,180)									(36,180)
Dividends on preferred stock			$ (1,968)									$ (1,968)
Shares Granted, Value, Share-based Payment Arrangement, after Forfeiture	3,342							2,717		0			625
Stock Issued During Period, Value, Stock Options Exercised	0							0					0
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	(156)												(156)
Stock Repurchased During Period, Value	0												0
Ending Balance at Sep. 30, 2020	$ 3,219,690			$ 145,037		$ 937		$ 1,106,473		$ 2,055,620			$ (140,414)		$ 52,037
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared	$ 0.40
Dividends on preferred stock (in dollars per share)			$ 328.125

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net income	$ 160,577	$ 292,250
Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]
Provision for credit losses	138,750	31,800
Deferred Income Tax Expense (Benefit)	(29,976)	3,647
Depreciation, Amortization and Accretion, Net	27,448	28,159
Accretion (Amortization) of Discounts and Premiums, Investments	47,178	36,667
Share-based Payment Arrangement, Noncash Expense	9,356	9,684
Gains (Losses) on Sales of Other Real Estate	(1,073)	(827)
Gain (Loss) on Disposition of Property Plant Equipment	184	1,213
Available-for-sale Securities, Gross Realized Gains	(8)	0
Life Insurance, Corporate or Bank Owned, Change in Value	(10,899)	(10,942)
Bank Owned Life Insurance Income	(352)	(4,626)
Gain (Loss) on Sales of Loans, Net	(14,185)	(3,829)
Proceeds from Sale of Loans Held-for-sale	342,747	129,700
Payments for Origination of Mortgage Loans Held-for-sale	(324,319)	(146,746)
Increase (Decrease) in Financial Instruments Used in Operating Activities	8,634	(4,274)
Increase (Decrease) in Derivative Assets and Liabilities	(172,647)	(164,977)
Increase (Decrease) in Other Operating Assets	23,353	(25,803)
Increase (Decrease) in Other Accounts Payable and Accrued Liabilities	(43,272)	(39,033)
Net Cash Provided by (Used in) Operating Activities, Total	161,496	132,063
Net Cash Provided by (Used in) Investing Activities [Abstract]
Payments to Acquire Debt Securities, Available-for-sale	(586,228)	(351,091)
Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale	422,572	394,369
Proceeds from Sale of Available-for-sale Securities	8,963	0
Payments to Acquire Held-to-maturity Securities	(1,005,535)	(1,289,977)
Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities	655,521	400,779
Payments for (Proceeds from) Federal Home Loan Bank Stock	59,435	32,302
Payments for (Proceeds from) Other Investing Activities	(7,423)	(4,040)
Payments for (Proceeds from) Other Loans and Leases	(1,869,715)	(1,147,426)
Proceeds of Other Loans and Leases Held-for-investment	6,414	20,542
Proceeds from Life Insurance Policy	1,625	9,193
Proceeds from Sale of Foreclosed Assets	8,047	10,901
Proceeds from Sale of Productive Assets	641	0
Payments to Acquire Property, Plant, and Equipment	(14,016)	(18,771)
Net Cash Provided by (Used in) Investing Activities, Total	(2,319,699)	(1,943,219)
Net Cash Provided by (Used in) Financing Activities [Abstract]
Increase (Decrease) in Deposits	3,590,551	1,421,819
Proceeds from FHLBank Borrowings, Financing Activities	3,775,000	5,725,000
Payments of FHLBank Borrowings, Financing Activities	(5,290,233)	(6,158,959)
Increase (Decrease) in Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Net	261,391	628,818
Proceeds from Issuance of Senior Long-term Debt	0	300,000
Payments of Debt Issuance Costs	0	(3,642)
Payments of Ordinary Dividends, Common Stock	(108,882)	(103,971)
Payments of Ordinary Dividends, Preferred Stock and Preference Stock	(5,906)	(5,906)
Proceeds from Stock Options Exercised	118	621
Payments for Repurchase of Common Stock	(76,556)	(13,003)
Payments for Repurchase of Equity, Share-based Compensation	(3,375)	(6,289)
Net Cash Provided by (Used in) Financing Activities, Total	2,142,108	1,784,488
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	(16,095)	(26,668)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Beginning Balance	257,895	329,499
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Ending Balance	241,800	302,831
Supplemental Cash Flow Information [Abstract]
Interest Paid, Excluding Capitalized Interest, Operating Activities	103,550	151,859
Income Taxes Paid	77,376	90,574
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Real Estate Owned, Transfer to Real Estate Owned	5,178	7,224
Transfer of Portfolio Loans and Leases to Held-for-sale	5,805	15,968
Payments for Deposits	4,657	0
Lease Obligation Incurred	0	157,234
Liabilities Assumed	$ 0	$ 178,208

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Nature of Operations Webster Financial Corporation (the Holding Company) is a bank holding company and financial holding company under the Bank Holding Company Act, incorporated under the laws of Delaware in 1986 and headquartered in Waterbury, Connecticut. Webster Bank, National Association (Webster Bank) is the principal consolidated subsidiary of Webster Financial Corporation. Webster Bank and its HSA Bank division deliver a wide range of banking, investment, and financial services to individuals, families, and businesses. Webster Bank serves consumer and business customers with mortgage lending, financial planning, trust, and investment services through a distribution network consisting of banking centers, ATMs, a customer care center, and a full range of web and mobile-based banking services throughout southern New England and Westchester County, New York. It also offers equipment financing, commercial real estate lending, asset-based lending, and treasury and payment solutions primarily in the eastern U.S. HSA Bank is a leading provider of HSAs, while also delivering health reimbursement arrangements, and flexible spending and commuter benefit account administration services to employers and individuals in all 50 states. Basis of Presentation The accounting and reporting policies of the Company that materially affect its financial statements conform with U.S. GAAP. The accompanying unaudited Condensed Consolidated Financial Statements of the Company have been prepared in conformity with the instructions for Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all the information and notes required by GAAP for complete financial statements and should be read in conjunction with the Company's Consolidated Financial Statements, and related Notes, for the year ended December 31, 2019, included in our Form 10-K filed with the SEC. There have been no changes to the Company's significant accounting policies from those described within that Form 10-K, except as described within the Recently Adopted Accounting Standards Updates section of this note. Certain prior period amounts have been reclassified to conform to the current year's presentation. These reclassifications had an immaterial effect on the Company's consolidated financial statements. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Loan Modifications Under the CARES Act and Interagency Statement The Coronavirus Aid, Relief, and Economic Security Act (CARES Act) Section 4013, and the Revised Interagency Statement on Loan Modifications and Reporting for Financial Institutions Working with Customers Affected by the Coronavirus. On March 27, 2020, the CARES Act, which provides relief from certain requirements under GAAP, was signed into law. Section 4013 of the CARES Act gives entities temporary relief from the accounting and disclosure requirements for troubled debt restructurings (TDRs) under ASC 310-40 in certain situations. In addition, on April 7, 2020, certain regulatory banking agencies issued an interagency statement that offers practical expedients for evaluating whether loan modifications in response to the COVID-19 pandemic are TDRs. The interagency statement was originally issued on March 22, 2020, but was revised to address the relationship between their original TDR guidance and the guidance in Section 4013 of the CARES Act. To qualify for TDR accounting and disclosure relief under the CARES Act, the applicable loan must not have been more than 30 days past due as of December 31, 2019, and the modification must be executed during the period beginning on March 1, 2020, and ending on the earlier of December 31, 2020, or the date that is 60 days after the termination date of the national emergency declared by the president on March 13, 2020, under the National Emergencies Act related to the outbreak of COVID-19. The CARES Act applies to modifications made as a result of COVID-19 including: forbearance agreements, interest rate modifications, repayment plans, and other arrangements to defer or delay payment of principal or interest. The interagency statement does not require the modification to be completed within a certain time period if it is related to COVID-19 and the loan was not more than 30 days past due as of the date of the Company’s implementation of its modification programs. Moreover, the interagency statement applies to short-term modifications including payment deferrals, fee waivers, extensions of repayment terms, or other insignificant payment delays as a result of COVID-19. The Company continues to apply section 4013 of the CARES Act and the interagency statement in connection with applicable modifications. For modifications that qualify under either the CARES Act or the interagency statement, TDR accounting and reporting is suspended through the period of the modification; however, the Company will continue to apply its existing non-accrual policies including consideration of the loan's past due status which is determined on the basis of the contractual terms of the loan. Once a loan has been contractually modified, the past due status is generally based on the updated terms including payment deferrals. Recently Adopted Accounting Standards Updates Effective January 1, 2020, the following new accounting guidance was adopted by the Company: ASU No. 2020-04, Reference Rate Reform (Topic 848) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The Update provides optional expedients and exceptions available to contracts, hedging relationships, and other transactions affected by reference rate reform. In addition to expedients for contract modifications, the Update allows for a one-time transfer or sale of held-to-maturity securities that reference an eligible rate. The Company will consider this one-time securities transfer along with other expedients available under the Update as the Company proceeds with reference rate reform activities. For additional information on reference rate reform refer to the risk factors previously disclosed in Webster's Annual Report on Form 10-K for the year ended December 31, 2019. The Update became effective during the first quarter 2020, and applies to contract modifications and amendments made as of the beginning of the reporting period including the Update issuance date, March 12, 2020, and applies through December 31, 2022. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments. The Update amends guidance on credit losses, hedge accounting, and recognition and measurement of financial instruments. The changes provide clarifications and codification improvements in relation to recently issued accounting updates. The amendments to the guidance on credit losses are considered in the paragraphs below related to our adoption of ASU 2016-13, and has been adopted concurrently with those Updates. The Company adopted the Update during the first quarter 2020 on a prospective basis. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40) - Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The Update aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The updated guidance also requires an entity to amortize the capitalized implementation costs as an expense over the term of the hosting arrangement and to present in the same income statement line item as the fees associated with the hosting arrangement. The Company adopted the Update during the first quarter 2020 on a prospective basis to all implementation costs incurred after the date of adoption. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2018-13, Fair Value Measurement (Topic 820) - Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement. The Update modifies the disclosure requirements for fair value measurements. The updated guidance no longer requires entities to disclose the amount and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy. However, it requires public companies to disclose changes in unrealized gains and losses for the period included in other comprehensive income (OCI) for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 measurements. The Company adopted the Update during the first quarter 2020 on a prospective basis. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment. The Update simplifies quantitative goodwill impairment testing by requiring entities to compare the fair value of a reporting unit with its carrying amount and recognize an impairment charge for any amount by which the carrying amount exceeds the fair value of a reporting unit, up to but not exceeding the amount of goodwill allocated to the reporting unit. The Update changes current guidance by eliminating the second step of the goodwill impairment analysis which involves calculating the implied fair value of goodwill determined in the same manner as the amount of goodwill recognized in a business combination upon acquisition. Entities still have the option to first perform a qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. The Company adopted the Update during the first quarter 2020 on a prospective basis. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments and subsequent ASUs issued to clarify this Topic. The Updates replace the existing incurred loss approach for recognizing credit losses with a new credit loss methodology known as the current expected credit loss (CECL) model. The CECL methodology requires earlier recognition of credit losses using a lifetime credit loss measurement approach for financial assets carried at amortized cost. The Updates also revised the accounting for credit losses on available-for-sale debt securities, which is outside the scope of the CECL methodology. The CECL accounting model applies to all assets measured at amortized cost including loans, net investments in leases, off balance sheet credit exposures, and held-to-maturity debt securities. CECL requires recognition of credit losses at purchase or origination using a lifetime credit loss measurement approach. The allowance for credit losses is based on the composition, characteristics, and credit quality of the loan and securities portfolios as of the reporting date and includes consideration of current economic conditions and reasonable and supportable forecasts at that date. The CECL methodology also requires consideration of a broader range of reasonable and supportable information to determine the allowance for credit losses including economic forecasts. Allowance for credit losses on loans and leases. Under CECL the Company determines its allowance for credit losses on loans and leases collectively, using pools of assets with similar risk characteristics. Loans that no longer match the risk profile of the pool are individually assessed for credit losses. Collective assessments are performed based on two portfolio segments, commercial loans and leases, and consumer loans. Expected losses within the commercial and consumer portfolios are collectively assessed using PD/LGD/EAD framework based on the portfolio or class of financing receivable. The Company’s lifetime credit loss models are based on historical data and incorporate forecasts of macroeconomic variables, qualitative factors, expected prepayments and recoveries. Macroeconomic variables are selected based on the correlation of the variables to credit losses for each class of financing receivable as follows: the commercial model uses unemployment, gross domestic product (GDP), and retail sales; the residential model uses the Case Shiller Home Price Index; home equity loan and line of credit models use interest rate spreads between U.S. Treasuries and corporate bonds and the home equity loan model also uses the Federal Housing Finance Agency (FHFA) home price index; personal loan and credit line models use the Case Shiller and FHFA home price indices. Forecasted economic scenarios are sourced from a third party. Data from the baseline forecast scenario is used in the modeled loss calculation. Qualitative factors are applied to further refine the expected loss calculation for each portfolio considering factors such as credit concentration, credit quality trends, the quality of internal loan reviews, the nature and volume of portfolio growth, staffing levels, underwriting exceptions, and economic considerations not reflected in the base loss model. Other qualitative adjustments may be applied for relevant facts and circumstances expected to impact credit losses. A two year reasonable and supportable forecast period is used for all loan and lease portfolios, subsequently, the expected loss models revert to historical loss rates on a linear basis over a one year period. Historical loss rates are based on approximately 10 years of recently available data and are updated annually. When the risk characteristics of a loan no longer match the characteristics of the collective pool, the loan is removed from the pool and individually assessed for credit losses. Generally, all non-accrual loans, TDRs, potential TDRs, loans with a charge-off, and collateral dependent loans are individually assessed. The individual assessment for credit impairment is generally based on a discounted cash flow approach unless the asset is collateral dependent. A loan is considered collateral dependent when repayment is expected to be provided substantially through the operation or sale of the collateral and the borrower is experiencing financial difficulty. Collateral dependent loans are individually assessed and the expected credit loss is based on the fair value of the collateral. The fair value is reduced for estimated costs to sell if the value of the collateral is expected to be realized through sale. The Company has elected to present accrued interest receivable separately from the amortized cost basis on the balance sheet and is not estimating an allowance for credit loss on accrued interest. This election applies to loans and leases as well as debt securities. The Company's non-accrual policies have not changed as a result of adopting the Updates. Allowance for credit losses on investment securities held-to-maturity. Held-to-maturity debt securities follow the CECL accounting model. Expected losses are calculated on a pooled basis using statistical models which include forecasted scenarios of future economic conditions. The forecasts revert to long-run loss rates implicitly through the economic scenario, generally over three years. If the risk of a held-to-maturity debt security no longer matches the collective assessment pool, it is removed and individually assessed for credit deterioration. A zero credit loss assumption is maintained for U.S. Treasuries and agency-backed securities in both the held-to-maturity and available-for-sale portfolios. The zero loss assumption is re-considered on a quarterly basis to ensure it is still appropriate. Securities are placed on non-accrual status when collection of principal and interest in accordance with contractual terms is doubtful, generally when principal or interest payments become 90 days delinquent unless the security is well secured and in process of collection, or sooner if management concludes circumstances indicate that the borrower may be unable to meet contractual principal or interest payments. Allowance for credit losses on unfunded loan commitments. Accounting for unfunded loan commitments also follows the CECL model, with an allowance recorded on commitments that are not unconditionally cancellable by the Company. 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. The allowance for credit losses on unfunded loan commitments is included in accrued expenses and other liabilities on the consolidated balance sheet and the related credit expense is recorded in other non-interest expense in the consolidated statements of income. Accounting for available-for-sale debt securities. The Updates revised the accounting for available-for-sale debt securities by eliminating the other-than-temporary impairment model, and requiring credit losses be presented as an allowance rather than a direct write-down of available-for-sale debt securities under certain circumstances. Available-for-sale debt securities continue to be recorded at fair value with changes in fair value reflected in OCI. When the fair value of an available-for-sale debt security falls below the amortized cost basis it is evaluated to determine if any of the decline in value is attributable to credit loss. Decreases in fair value attributable to credit loss are recorded directly to earnings with a corresponding allowance for credit losses, limited to the amount that the fair value is less than the amortized cost basis. If the credit quality subsequently improves the allowance is reversed up to a maximum of the previously recorded credit losses. Available-for-sale debt securities follow the same non-accrual policy as held-to-maturity debt securities. 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 recovering the amortized cost basis, the entire fair value adjustment will immediately be recognized in earnings with no corresponding allowance for credit losses. Impact of Adoption . The Company adopted the Updates during the first quarter 2020, using the modified retrospective method. Upon adoption, the Company recorded an increase in its allowance for credit losses as a cumulative effect adjustment. This adjustment, net of tax, reduced the Company's beginning total shareholders' equity at January 1, 2020. Upon adoption, the Company's allowance for credit losses reflected all credit losses expected over the lifetime of the Company's financial assets held at amortized cost. The total increase in allowance and corresponding decrease in equity did not have a material impact to the Company's regulatory capital amounts and ratios. Periods prior to January 1, 2020, are reported in accordance with previously applicable GAAP. The impact of the January 1, 2020, adoption entry is summarized in the table below: December 31, 2019 January 1, 2020 (In thousands) Pre-ASC 326 Adoption Impact of Adoption Reported Under ASC 326 Assets: Allowance for credit losses on investment securities held-to-maturity $ — $ (397) $ (397) Allowance for credit losses on loans and leases (209,096) (57,568) (266,664) Deferred tax assets, net 61,975 15,891 77,866 Liabilities and shareholders' equity: Accrued expenses and other liabilities 153,161 9,139 162,300 Retained earnings 2,061,352 (51,213) 2,010,139 For additional information on accounting for credit losses refer to Note 3: Investment Securities and Note 4: Loans and Leases. Accounting Standards Issued But Not Yet Adopted The following new accounting guidance, applicable to the Company, has been issued by the Financial Accounting Standards Board (FASB) but is pending adoption: ASU No. 2019-12, Income Taxes (Topic 740) - Simplifying the Accounting for Income Taxes. The Update provides simplification to the accounting for income taxes related to a variety of topics and makes minor codification improvements. Changes include a requirement that the effects of an enacted change in tax law be reflected in the computation of the annual effective tax rate in the first interim period that includes the enactment date of the new legislation and clarification on presentation of non-income based taxes. The Update will be effective for the Company on January 1, 2021. The Company does not expect this Update to have a material impact on its consolidated financial statements. ASU No. 2018-14, Compensation-Retirement Benefits - Defined Benefit Plan - General (Subtopic 715-20) - Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans. The Update modifies disclosure requirements for employers that sponsor defined benefit pension and other postretirement plans. The Update will be effective for the Company on January 1, 2021. The Company does not expect this Update to have a material impact on its consolidated financial statements.

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2020
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 meet the definition of a variable interest entity (VIE). Consolidated Rabbi Trust. The Company established a Rabbi Trust to meet the obligations due under its Deferred Compensation Plan for Directors and Officers and to mitigate the expense volatility of the aforementioned plan. The funding of the Rabbi Trust and the discontinuation of the Deferred Compensation Plan for Directors and Officers occurred during 2012. Invested assets in the Rabbi Trust primarily consist of mutual funds that invest in equity and fixed income securities. The Company is considered the primary beneficiary of the Rabbi Trust as it has the power to direct the activities of the Rabbi Trust that significantly affect the VIE's economic performance and it has the obligation to absorb losses of the VIE that could potentially be significant to the VIE. The Company consolidates the invested assets of the trust along with the total deferred compensation obligations and includes them in accrued interest receivable and other assets, and accrued expenses and other liabilities, respectively, on the consolidated balance sheet. Earnings in the Rabbi Trust, including appreciation or depreciation, are reflected as other non-interest income, and changes in the corresponding liability are reflected as compensation and benefits, in the consolidated income statement. Refer to Note 14: Fair Value Measurements for additional information. Non-Consolidated Tax Credit - Finance Investments. The Company makes non-marketable equity investments in entities that finance affordable housing and other community development projects and provide a return primarily through the realization of tax benefits. In most instances the investments require the funding of capital commitments in the future. While the Company's investment in an entity may exceed 50% of its outstanding equity interests, the entity is not consolidated as Webster is not involved in its management. For these investments, the Company determined it is not the primary beneficiary due to its inability to direct the activities that most significantly impact the economic performance of the VIEs. The Company applies the proportional amortization method to account for its investments in qualified affordable housing projects. At September 30, 2020 and December 31, 2019, the aggregate carrying value of the Company's tax credit-finance investments was $38.5 million and $42.5 million, respectively, which represents the Company's maximum exposure to loss. At September 30, 2020 and December 31, 2019, unfunded commitments have been recognized, totaling $14.2 million and $15.1 million, respectively, and are included in accrued expenses and other liabilities on the consolidated balance sheet. 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 trust is a VIE in which the Company is not the primary beneficiary. The trust's only assets are junior subordinated debentures issued by the Company, which were acquired by the trust using the proceeds from the issuance of the trust preferred securities and common stock. The junior subordinated debentures are included in long-term debt on the consolidated balance sheet, and the related interest expense is reported as interest expense on long-term debt in the consolidated income statement. Other Non-Marketable Investments. The Company invests in various alternative investments in which it holds a variable interest. These investments are non-public entities which cannot be redeemed since the Company’s investment is distributed as the underlying equity is liquidated. For these investments, the Company has determined it is not the primary beneficiary due to its inability to direct the activities that most significantly impact the economic performance of the VIEs. At September 30, 2020 and December 31, 2019, the aggregate carrying value of the Company's other non-marketable investments in VIEs was $28.4 million and $21.8 million, respectively, and the total exposure of the Company's other non-marketable investments in VIEs, including unfunded commitments, was $70.5 million and $64.2 million, respectively. Refer to Note 14: Fair Value Measurements for additional information. The Company's equity interests in Other Non-Marketable Investments, as well as Tax Credit-Finance Investments and Webster Statutory Trust, are included in accrued interest receivable and other assets in the consolidated balance sheet. For a description of the Company's accounting policy regarding the consolidation of VIEs, refer to Note 1 to the Consolidated Financial Statements included in its Form 10-K, for the year ended December 31, 2019.

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities Held-to-Maturity Securities A summary of the amortized cost, fair value, and allowance for credit losses on investment securities held-to-maturity is presented below: At September 30, 2020 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value Allowance (2) Net Carrying Value Agency CMO $ 116,020 $ 2,743 $ (261) $ 118,502 $ — $ 116,020 Agency MBS 2,595,711 155,221 (106) 2,750,826 — 2,595,711 Agency CMBS 2,033,826 63,401 (599) 2,096,628 — 2,033,826 Municipal bonds and notes 750,847 53,457 — 804,304 306 750,541 CMBS 227,030 9,126 — 236,156 — 227,030 Held-to-maturity securities $ 5,723,434 $ 283,948 $ (966) $ 6,006,416 $ 306 $ 5,723,128 At December 31, 2019 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value Allowance (2) Net Carrying Value Agency CMO $ 167,443 $ 1,123 $ (1,200) $ 167,366 $ — $ 167,443 Agency MBS 2,957,900 60,602 (8,733) 3,009,769 — 2,957,900 Agency CMBS 1,172,491 6,444 (5,615) 1,173,320 — 1,172,491 Municipal bonds and notes 740,431 32,709 (21) 773,119 — 740,431 CMBS 255,653 2,278 (852) 257,079 — 255,653 Held-to-maturity securities $ 5,293,918 $ 103,156 $ (16,421) $ 5,380,653 $ — $ 5,293,918 (1) Amortized cost excludes accrued interest receivable of $18.5 million and $21.8 million at September 30, 2020 and December 31, 2019, respectively, which is included in accrued interest and other assets in the consolidated balance sheet. (2) The Company adopted the new accounting standard for credit losses on January 1, 2020. For periods subsequent to adoption Allowance is calculated under the CECL methodology and the resulting provision includes expected credit losses on held-to-maturity securities. The prior period did not have an allowance under applicable GAAP for that period. 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. Securities with unrealized losses and no allowance are considered to be of high credit quality, and therefore, no credit loss as of September 30, 2020. The current unrealized loss position of certain agency securities and non-agency CMBS with no credit loss allowance can be attributed to the changing interest rate environment. An allowance for credit losses on investment securities held-to-maturity of $397 thousand was recorded for certain Municipal bonds and notes to account for expected lifetime credit loss upon adoption of the new accounting standard for credit losses. Expected lifetime credit loss on investment securities held-to-maturity is primarily attributed to securities not rated. The following table summarizes the activity in the allowance for credit losses on investment securities held-to-maturity: Three months ended September 30, 2020 Nine months ended September 30, 2020 (In thousands) Municipal bonds and notes Municipal bonds and notes Balance beginning of period $ 309 $ — Adoption of ASU No. 2016-13 (CECL) — 397 Recovery of credit losses (3) (91) Balance end of period $ 306 $ 306 Credit Quality Information The Company monitors the credit quality of held-to-maturity debt securities through credit ratings by Standard & Poor's Rating Services (S&P), Moody's Investor Services (Moody's), Fitch Ratings, Inc., Kroll Bond Rating Agency, or DBRS Inc. Credit ratings express opinions about the credit quality of a security. Investment grade securities are rated BBB- or higher by S&P, or Baa3 or higher by Moody's, and generally considered by the rating agencies and market participants to be of low credit risk. Conversely, securities rated below investment grade, labeled as speculative grade by the rating agencies, are considered to have distinctively higher credit risk than investment grade securities. Securities shown below that are not rated are backed by U.S. Treasury obligations, and credit quality indicators are updated at each quarter end. The following table summarizes credit ratings for amortized cost of held-to-maturity debt securities according to their lowest public credit rating as of September 30, 2020: Investment Grade (In thousands) Aaa Aa1 Aa2 Aa3 A1 A2 A3 Baa2 Not Rated Agency CMOs $ — $ 116,020 $ — $ — $ — $ — $ — $ — $ — Agency MBS — 2,595,711 — — — — — — — Agency CMBS — 2,033,826 — — — — — — — Municipal bonds and notes 209,751 165,261 201,423 117,320 41,697 8,663 2,066 285 4,381 CMBS 227,030 — — — — — — — — Total held-to-maturity $ 436,781 $ 4,910,818 $ 201,423 $ 117,320 $ 41,697 $ 8,663 $ 2,066 $ 285 $ 4,381 As of September 30, 2020, none of the held-to-maturity investment securities were in non-accrual status. Contractual Maturities The amortized cost and fair value of held-to-maturity debt securities by contractual maturity are set forth below: At September 30, 2020 (In thousands) Amortized Fair Due in one year or less $ 1,085 $ 1,089 Due after one year through five years 5,340 5,611 Due after five through ten years 279,056 295,103 Due after ten years 5,437,953 5,704,613 Total held-to-maturity debt securities $ 5,723,434 $ 6,006,416 For the maturity schedule above, investment securities which 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 maturity date presentation as borrowers have the right to repay obligations with or without prepayment penalties. Available-for-Sale Securities A summary of the amortized cost and fair value of available-for-sale securities is presented below: At September 30, 2020 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value (2) Agency CMO $ 166,623 $ 6,908 $ (177) $ 173,354 Agency MBS 1,446,100 81,533 (363) 1,527,270 Agency CMBS 1,024,133 27,621 — 1,051,754 CMBS 464,071 794 (9,840) 455,025 CLO 85,601 1 (1,241) 84,361 Corporate debt 14,551 — (2,098) 12,453 Available-for-sale securities $ 3,201,079 $ 116,857 $ (13,719) $ 3,304,217 At December 31, 2019 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value (2) Agency CMO $ 184,500 $ 2,218 $ (917) $ 185,801 Agency MBS 1,580,743 35,456 (4,035) 1,612,164 Agency CMBS 587,974 513 (6,935) 581,552 CMBS 432,085 38 (252) 431,871 CLO 92,628 45 (468) 92,205 Corporate debt 23,485 — (1,245) 22,240 Available-for-sale securities $ 2,901,415 $ 38,270 $ (13,852) $ 2,925,833 (1) Amortized cost excludes accrued interest receivable of $7.4 million and $8.1 million at September 30, 2020 and December 31, 2019, respectively, which is included in accrued interest and other assets in the consolidated balance sheet. (2) Fair value represents net carrying value as there is no allowance for credit losses recorded on investment securities available-for-sale, as the securities are high credit quality, investment grade. Fair Value and Unrealized Losses The following tables provide information on fair value and unrealized losses for the individual available-for-sale securities with an unrealized loss, for which an allowance for credit losses on investment securities available-for-sale has not been recorded, aggregated by classification and length of time that the individual investment securities have been in a continuous unrealized loss position: At September 30, 2020 Less Than Twelve Months Twelve Months or Longer Total (Dollars in thousands) Fair Unrealized Fair Unrealized # of Fair Unrealized Agency CMO $ 11,358 $ (92) $ 7,935 $ (85) 3 $ 19,293 $ (177) Agency MBS 30,077 (208) 11,591 (155) 30 41,668 (363) Agency CMBS — — — — — — — CMBS 407,322 (9,205) 22,868 (635) 38 430,190 (9,840) CLO 65,711 (589) 18,048 (652) 4 83,759 (1,241) Corporate debt 3,892 (371) 8,561 (1,727) 3 12,453 (2,098) Available-for-sale in unrealized loss position $ 518,360 $ (10,465) $ 69,003 $ (3,254) 78 $ 587,363 $ (13,719) At December 31, 2019 Less Than Twelve Months Twelve Months or Longer Total (Dollars in thousands) Fair Unrealized Fair Unrealized # of Fair Unrealized Agency CMO $ 36,447 $ (352) $ 32,288 $ (565) 9 $ 68,735 $ (917) Agency MBS 41,408 (193) 299,674 (3,842) 79 341,082 (4,035) Agency CMBS 174,406 (1,137) 357,717 (5,798) 34 532,123 (6,935) CMBS 355,260 (232) 7,480 (20) 29 362,740 (252) CLO — — 43,232 (468) 2 43,232 (468) Corporate debt — — 22,240 (1,245) 4 22,240 (1,245) Available-for-sale in unrealized loss position $ 607,521 $ (1,914) $ 762,631 $ (11,938) 157 $ 1,370,152 $ (13,852) Unrealized losses on available-for-sale debt securities presented in the previous table have not been recognized in the consolidated statements of income because the securities are high credit quality, investment grade securities that the Company does not intend to sell and will not be required to sell prior to their anticipated recovery, and the decline in fair value is primarily attributable to wider spreads in selected asset classes. Fair value is expected to recover as the securities approach maturity. As of September 30, 2020, none of the available-for-sale investment securities were in non-accrual status. Contractual Maturities The amortized cost and fair value of available-for-sale debt securities by contractual maturity are set forth below: At September 30, 2020 (In thousands) Amortized Fair Due in one year or less $ — $ — Due after one year through five years 601 602 Due after five through ten years 263,579 257,909 Due after ten years 2,936,899 3,045,706 Total available-for-sale debt securities $ 3,201,079 $ 3,304,217 For the maturity schedule above, investment securities which 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 maturity date presentation as borrowers have the right to repay obligations with or without prepayment penalties. Sales of Available-for Sale Investment Securities For the nine months ended September 30, 2020, proceeds from sales of available-for-sale securities were $9.0 million, which resulted in realized gains of $8.0 thousand. There were no sales during the three months ended September 30, 2020, or the three and nine months ended September 30, 2019. Other Information At September 30, 2020, the Company had a carrying value of $1.3 billion in callable debt securities in its CMBS, CLO, and municipal bond portfolios. The Company considers this prepayment risk in the evaluation of its interest rate risk profile. Investment securities with a carrying value totaling $4.0 billion at September 30, 2020 and $2.7 billion at December 31, 2019 were pledged to secure public funds, trust deposits, repurchase agreements, and for other purposes, as required or permitted by law.

Loans and Leases

Loans and Leases	9 Months Ended
	Sep. 30, 2020
Loans and Leases Receivable Disclosure [Abstract]
Loans and Leases	Loans and Leases The following table summarizes loans and leases: (In thousands) At September 30, At December 31, 2019 Commercial non-mortgage $ 7,124,365 $ 5,296,611 Asset-based 889,711 1,046,886 Commercial real estate 6,307,567 5,949,339 Equipment financing 598,473 537,341 Total commercial portfolio 14,920,116 12,830,177 Residential 4,885,821 4,972,685 Home equity 1,867,969 2,014,544 Other consumer 178,117 219,580 Total consumer portfolio 6,931,907 7,206,809 Loans and leases (1) (2) (3) $ 21,852,023 $ 20,036,986 (1) Loan balances include net deferred (fees)/costs and net (premiums)/discounts of $(14.1) million and $17.6 million at September 30, 2020 and December 31, 2019, respectively. (2) At September 30, 2020 the Company had pledged $7.9 billion of eligible loans as collateral to support borrowing capacity at the Federal Home Loan Bank (FHLB) of Boston and the Federal Reserve Bank (FRB) of Boston. (3) Loan balances exclude accrued interest receivable of $56.6 million and $59.0 million at September 30, 2020 and December 31, 2019, respectively, which is included in accrued interest and other assets in the consolidated balance sheet. Equipment financing includes net investment in leases of $235.6 million, with total undiscounted cash flows, primarily due within the next five years, amounting to $255.9 million, at September 30, 2020. This lessor activity resulted in interest income of $1.8 million and $1.2 million for the three months ended September 30, 2020 and 2019, respectively, and $5.2 million and $4.0 million for the nine months ended September 30, 2020 and 2019, respectively. Loans and Leases Aging The following tables summarize the aging of loans and leases: At September 30, 2020 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Past Due and Non-accrual Current Total Loans Commercial non-mortgage $ 1,027 $ 67 $ — $ 67,849 $ 68,943 $ 7,055,422 $ 7,124,365 Asset-based — — — 3,760 3,760 885,951 889,711 Commercial real estate 330 — — 8,799 9,129 6,298,438 6,307,567 Equipment financing 183 2,550 — 7,182 9,915 588,558 598,473 Residential 4,478 4,787 — 41,554 50,819 4,835,002 4,885,821 Home equity 5,180 1,572 — 32,853 39,605 1,828,364 1,867,969 Other consumer 1,069 556 — 679 2,304 175,813 178,117 Total $ 12,267 $ 9,532 $ — $ 162,676 $ 184,475 $ 21,667,548 $ 21,852,023 At December 31, 2019 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Past Due and Non-accrual Current Total Loans Commercial non-mortgage $ 2,094 $ 617 $ — $ 59,369 $ 62,080 $ 5,234,531 $ 5,296,611 Asset-based — — — 139 139 1,046,747 1,046,886 Commercial real estate 1,256 454 — 11,563 13,273 5,936,066 5,949,339 Equipment financing 5,493 292 — 5,433 11,218 526,123 537,341 Residential 7,166 6,441 — 43,193 56,800 4,915,885 4,972,685 Home equity 8,267 5,551 — 30,170 43,988 1,970,556 2,014,544 Other consumer 4,269 807 — 1,192 6,268 213,312 219,580 Total $ 28,545 $ 14,162 $ — $ 151,059 $ 193,766 $ 19,843,220 $ 20,036,986 The following table provides additional detail related to loans and leases on non-accrual status: At September 30, 2020 At December 31, 2019 (In thousands) Nonaccrual Nonaccrual With No Allowance Nonaccrual Nonaccrual With No Allowance Commercial non-mortgage $ 67,849 $ 12,136 $ 59,369 $ 13,584 Asset-based 3,760 — 139 — Commercial real estate 8,799 2,729 11,563 4,717 Equipment financing 7,182 2,659 5,433 2,159 Total commercial portfolio 87,590 17,524 76,504 20,460 Residential 41,554 30,234 43,193 19,271 Home equity 32,853 25,981 30,170 15,195 Other consumer 679 31 1,192 — Total consumer portfolio 75,086 56,246 74,555 34,466 Total $ 162,676 $ 73,770 $ 151,059 $ 54,926 Interest on non-accrual residential and home equity loans that would have been recorded as additional interest income had the loans been current in accordance with the original terms totaled $3.4 million and $3.1 million for the three months ended September 30, 2020 and 2019, respectively, and $9.0 million and $8.9 million for the nine months ended September 30, 2020 and 2019, respectively. Refer to Note 1 to the Consolidated Financial Statements included in the Company's Form 10-K, for the year ended December 31, 2019, for details of non-accrual policies. Allowance for Credit Losses on Loans and Leases The following tables summarize the activity in, as well as the loan and lease balances that were evaluated for, ACL on loans and leases: At or for the three months ended September 30, 2020 At or for the three months ended September 30, 2019 (In thousands) Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total ACL on loans and leases: Balance, beginning of period $ 291,520 $ 67,002 $ 358,522 $ 164,344 $ 47,327 $ 211,671 Adoption of ASU No. 2016-13 (CECL) — — — — — — Provision charged to expense 31,618 (8,865) 22,753 10,603 697 11,300 Charge-offs (13,494) (2,263) (15,757) (11,323) (4,637) (15,960) Recoveries 2,025 2,268 4,293 176 1,965 2,141 Balance, end of period $ 311,669 $ 58,142 $ 369,811 $ 163,800 $ 45,352 $ 209,152 At or for the nine months ended September 30, 2020 At or for the nine months ended September 30, 2019 (In thousands) Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total ACL on loans and leases: Balance, beginning of period $ 161,669 $ 47,427 $ 209,096 $ 164,073 $ 48,280 $ 212,353 Adoption of ASU No. 2016-13 (CECL) 34,024 23,544 57,568 — — — Provision charged to expense 147,466 (8,625) 138,841 26,513 5,287 31,800 Charge-offs (34,362) (9,630) (43,992) (28,263) (15,113) (43,376) Recoveries 2,872 5,426 8,298 1,477 6,898 8,375 Balance, end of period $ 311,669 $ 58,142 $ 369,811 $ 163,800 $ 45,352 $ 209,152 Individually evaluated for impairment 18,303 4,376 22,679 15,467 4,899 20,366 Collectively evaluated for impairment $ 293,366 $ 53,766 $ 347,132 $ 148,333 $ 40,453 $ 188,786 Loan and lease balances: Individually evaluated for impairment $ 158,324 $ 149,583 $ 307,907 $ 139,129 $ 131,502 $ 270,631 Collectively evaluated for impairment 14,761,792 6,782,324 21,544,116 12,268,839 7,012,176 19,281,015 Loans and leases $ 14,920,116 $ 6,931,907 $ 21,852,023 $ 12,407,968 $ 7,143,678 $ 19,551,646 Credit Quality Indicators. To measure credit risk for the commercial, commercial real estate, and equipment financing portfolios, the Company employs a dual grade credit risk grading system for estimating the PD and the LGD. The Company's credit risk grading system has not changed with the adoption of CECL. 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)-(6) are considered pass ratings, and (7)-(10) are considered criticized as defined by the regulatory agencies. Risk ratings, assigned to differentiate risk within the portfolio, are reviewed on an ongoing basis and revised to reflect changes in a borrowers’ current financial position and outlook, risk profile, and the related collateral and structural position. Loan officers review updated financial information 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. A (7) "Special Mention" credit has the potential weakness that, if left uncorrected, may result in deterioration of the repayment prospects for the asset. A (8) "Substandard" asset has a well-defined weakness that jeopardizes the full repayment of the debt. An asset rated (9) "Doubtful" has all of the same weaknesses as a substandard credit with the added characteristic that the weakness makes collection or liquidation in full, given current facts, conditions, and values, improbable. Assets classified as (10) "Loss" in accordance with regulatory guidelines are considered uncollectible and charged off. For residential and consumer loans, the most relevant credit characteristic is FICO score. FICO scores are a widely used credit score and range from 300 to 850. A lower FICO score is indicative of higher credit risk. FICO scores are updated at least quarterly. The following table summarizes commercial, commercial real estate, and equipment financing loans and leases segregated by origination year and risk rating exposure under the Composite Credit Risk Profile grades as of September 30, 2020: (In thousands) 2020 2019 2018 2017 2016 Prior Revolving Loans Amortized Cost Basis Total Commercial non-mortgage Pass $ 2,519,566 $ 1,156,057 $ 1,013,841 $ 553,942 $ 257,230 $ 297,765 $ 912,007 $ 6,710,408 Special mention 817 73,688 20,314 341 8,422 2,302 21,233 127,117 Substandard 1,369 33,658 68,305 75,071 23,138 33,137 51,996 286,674 Doubtful — — — 166 — — — 166 Total commercial non-mortgage 2,521,752 1,263,403 1,102,460 629,520 288,790 333,204 985,236 7,124,365 Asset-based Pass 14,848 21,854 22,595 11,635 11,039 22,667 714,476 819,114 Special mention — 1,667 800 — — 978 63,392 66,837 Substandard — — — — — — 3,760 3,760 Total asset-based 14,848 23,521 23,395 11,635 11,039 23,645 781,628 889,711 Commercial real estate Pass 646,507 1,473,602 1,296,427 605,375 595,915 1,329,377 28,106 5,975,309 Special mention 22 10,382 48,409 27,364 35,796 76,243 — 198,216 Substandard 821 989 23,095 68,828 2,444 37,865 — 134,042 Total commercial real estate 647,350 1,484,973 1,367,931 701,567 634,155 1,443,485 28,106 6,307,567 Equipment financing Pass 203,498 144,384 75,993 31,921 52,328 26,319 — 534,443 Special mention 12,492 13,014 8,471 1,834 1,932 788 — 38,531 Substandard 2,380 5,498 5,563 2,430 4,802 4,826 — 25,499 Total equipment financing 218,370 162,896 90,027 36,185 59,062 31,933 — 598,473 Total commercial portfolio $ 3,402,320 $ 2,934,793 $ 2,583,813 $ 1,378,907 $ 993,046 $ 1,832,267 $ 1,794,970 $ 14,920,116 The following table summarizes residential and consumer loans segregated by origination year and risk rating exposure under FICO score groupings as of September 30, 2020: (In thousands) 2020 2019 2018 2017 2016 Prior Revolving Loans Amortized Cost Basis Total Residential 800+ $ 253,913 $ 314,759 $ 69,592 $ 205,691 $ 316,264 $ 905,892 $ — $ 2,066,111 740-799 458,499 355,548 81,018 164,777 194,784 516,385 — 1,771,011 670-739 161,600 144,798 43,790 77,823 80,481 283,164 — 791,656 580-669 12,316 19,803 7,260 12,010 11,836 102,055 — 165,280 579 and below — 21,363 676 3,771 3,250 62,703 — 91,763 Total residential 886,328 856,271 202,336 464,072 606,615 1,870,199 — 4,885,821 Home equity 800+ 22,727 17,095 27,269 18,031 19,328 66,906 564,318 735,674 740-799 20,580 16,472 23,739 11,659 12,765 49,507 446,759 581,481 670-739 12,122 10,847 10,808 10,506 9,290 45,013 285,776 384,362 580-669 447 2,257 3,346 2,297 1,964 19,707 91,009 121,027 579 and below 100 524 879 1,337 835 7,707 34,043 45,425 Total home equity 55,976 47,195 66,041 43,830 44,182 188,840 1,421,905 1,867,969 Other consumer 800+ 1,345 3,436 1,901 581 115 173 6,851 14,402 740-799 10,419 17,858 9,665 1,491 503 344 6,402 46,682 670-739 21,089 49,734 19,855 4,158 1,616 520 5,676 102,648 580-669 2,440 4,247 1,744 600 253 180 1,623 11,087 579 and below 717 513 250 66 35 225 1,492 3,298 Total other consumer 36,010 75,788 33,415 6,896 2,522 1,442 22,044 178,117 Total consumer portfolio 978,314 979,254 301,792 514,798 653,319 2,060,481 1,443,949 6,931,907 Total commercial portfolio 3,402,320 2,934,793 2,583,813 1,378,907 993,046 1,832,267 1,794,970 14,920,116 Total loans and leases $ 4,380,634 $ 3,914,047 $ 2,885,605 $ 1,893,705 $ 1,646,365 $ 3,892,748 $ 3,238,919 $ 21,852,023 Individually Assessed Loans and Leases The following tables summarize individually assessed loans and leases: At September 30, 2020 (In thousands) Unpaid Amortized Cost Amortized Cost No Allowance Amortized Cost With Allowance Related Commercial non-mortgage $ 160,667 $ 125,799 $ 28,937 $ 96,862 $ 15,833 Asset-based 4,114 3,760 — 3,760 459 Commercial real estate 24,865 21,583 12,679 8,904 1,613 Equipment financing 7,661 7,182 2,659 4,523 398 Residential 110,542 100,443 63,457 36,986 3,293 Home equity 111,715 48,461 36,477 11,984 1,012 Other consumer 2,321 679 30 649 71 Total $ 421,885 $ 307,907 $ 144,239 $ 163,668 $ 22,679 At December 31, 2019 (In thousands) Unpaid Amortized Cost Amortized Cost No Allowance Amortized Cost With Allowance Related Commercial non-mortgage $ 140,096 $ 102,254 $ 29,739 $ 72,515 $ 7,862 Asset-based 465 139 — 139 5 Commercial real estate 29,292 23,297 14,818 8,479 1,143 Equipment financing 5,591 5,433 2,159 3,274 418 Residential 98,790 90,096 56,231 33,865 3,618 Home equity 38,503 35,191 27,672 7,519 1,203 Other consumer (1) — — — — — Total $ 312,737 $ 256,410 $ 130,619 $ 125,791 $ 14,249 (1) Partially charged-off other consumer loans were included in collectively evaluated for impairment at December 31, 2019. The following table summarizes average amortized cost and interest income recognized for individually assessed loans and leases: Three months ended September 30, Nine months ended September 30, 2020 2019 2020 2019 (In thousands) Average Accrued Cash Basis Interest Income Average Accrued Cash Basis Interest Income Average Accrued Cash Basis Interest Income Average Accrued Cash Basis Interest Income Commercial non-mortgage $ 127,676 $ 954 $ — $ 102,996 $ 751 $ — $ 114,027 $ 2,882 $ — $ 103,772 $ 2,515 $ — Asset-based 1,949 — — 4,673 — — 1,950 — — 4,694 — — Commercial real estate 24,555 192 — 15,051 60 — 22,440 507 — 13,526 194 — Equipment financing 7,488 — — 4,718 — — 6,308 — — 5,901 — — Residential 103,608 741 289 97,917 862 271 95,270 2,352 1,149 99,599 2,682 817 Home equity 49,309 302 297 36,584 247 246 41,826 1,002 1,540 37,490 803 767 Other consumer 948 13 — — — — 340 30 — — — — Total $ 315,533 $ 2,202 $ 586 $ 261,939 $ 1,920 $ 517 $ 282,161 $ 6,773 $ 2,689 $ 264,982 $ 6,194 $ 1,584 Collateral Dependent Loans and Leases. A loan is considered collateral dependent when the borrower is experiencing financial difficulty and repayment is substantially expected through the operation or sale of collateral. A collateral dependent loan is individually assessed based on the fair value of the collateral, less costs to sell, as of the reporting date. Commercial non-mortgage, asset based, and equipment financing are collateralized by equipment, inventory, receivables, or other non-real estate assets. Commercial real estate, residential, and home equity are collateralized by real estate. Collateral value on collateral dependent loans and leases was $135.3 million at September 30, 2020 and $109.8 million at December 31, 2019. The following table summarizes whether, or not, individually assessed loans and leases are collateral dependent: At September 30, 2020 At December 31, 2019 (In thousands) Collateral Dependent Not Considered Collateral Dependent Total Collateral Dependent Not Considered Collateral Dependent Total Commercial non-mortgage $ 11,337 $ 114,462 $ 125,799 $ 10,682 $ 91,572 $ 102,254 Asset-based — 3,760 3,760 — 139 139 Commercial real estate 15,708 5,875 21,583 14,097 9,200 23,297 Equipment financing — 7,182 7,182 — 5,433 5,433 Residential 35,379 65,064 100,443 17,635 72,461 90,096 Home equity 28,857 19,604 48,461 17,136 18,055 35,191 Other consumer — 679 679 — — — Total amortized cost of CDA $ 91,281 $ 216,626 $ 307,907 $ 59,550 $ 196,860 $ 256,410 Troubled Debt Restructurings The following table summarizes information for TDRs: (In thousands) At September 30, At December 31, 2019 Accrual status $ 143,544 $ 136,449 Non-accrual status 101,750 100,989 Total TDRs $ 245,294 $ 237,438 Specific reserves for TDRs included in the balance of ACL on loans and leases $ 17,092 $ 12,956 Additional funds committed to borrowers in TDR status 15,345 4,856 The portion of TDRs deemed to be uncollectible, $7.8 million and $11.0 million for the three months ended September 30, 2020 and 2019, respectively, and $10.8 million and $16.7 million for the nine months ended September 30, 2020 and 2019, respectively, were charged off. The following table provides information on the type of concession for loans and leases modified as TDRs: Three months ended September 30, Nine months ended September 30, 2020 2019 2020 2019 Number of Post- Modification Recorded Investment (1) Number of Post- Modification Recorded Investment (1) Number of Post- Modification Recorded Investment (1) Number of Post- Modification Recorded Investment (1) (Dollars in thousands) Commercial non-mortgage Extended Maturity — $ — 2 $ 29 6 $ 507 8 $ 222 Adjusted Interest Rate — — 1 12 — — 2 112 Maturity/Rate Combined 2 333 3 225 7 607 6 296 Other (2) 1 6 6 30,586 24 40,128 25 64,642 Commercial real estate Extended Maturity — — — — 1 72 — — Maturity/Rate Combined — — — — 1 278 — — Other (2) 3 306 1 2,180 3 306 3 4,816 Residential Extended Maturity 1 134 1 67 3 485 5 1,007 Maturity/Rate Combined 4 425 1 368 9 1,123 14 2,216 Other (2) 2 202 2 243 22 3,877 6 785 Home equity Extended Maturity 1 31 1 134 3 188 5 504 Maturity/Rate Combined 1 15 2 30 2 28 4 140 Other (2) 15 506 8 375 89 6,018 27 1,595 Total TDRs 30 $ 1,958 28 $ 34,249 170 $ 53,617 105 $ 76,335 (1) Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs as a result of the restructurings was not significant. (2) Other includes covenant modifications, forbearance, loans discharged under Chapter 7 bankruptcy, or other concessions. There were no significant amounts of loans and leases modified as TDRs within the previous 12 months and for which there was a payment default for the three and nine months ended September 30, 2020, while there were 4 loans and leases in the commercial portfolio with an amortized cost of $3.9 million and one loan in the consumer portfolio with an amortized cost of $0.1 million for the three and nine months ended September 30, 2019. TDRs in commercial, commercial real estate, and equipment financing segregated by risk rating exposure is as follows: (In thousands) At September 30, 2020 At December 31, 2019 Pass $ 12,591 $ 3,952 Special Mention — 63 Substandard 111,613 104,277 Doubtful 166 3,860 Total $ 124,370 $ 112,152

Transfers of Financial Assets

Transfers of Financial Assets	9 Months Ended
	Sep. 30, 2020
Transfers and Servicing [Abstract]
Transfers of Financial Assets	Transfers of Financial Assets The Company sells financial assets in the normal course of business, primarily residential mortgage loans sold to government-sponsored enterprises through established programs and securitizations. Residential mortgage origination fees, adjustments for changes in fair value, and gain or loss on loans sold are included as mortgage banking activities in the consolidated statement of income. The Company may be required to repurchase a loan in the event of certain breaches of the representations and warranties, or in the event of default of the borrower within 90 days of sale, as provided for in the sale agreements. A reserve for loan repurchases provides for estimated losses pertaining to the potential repurchase of loans associated with the Company’s mortgage banking activities. The reserve reflects loan repurchase requests received by the Company for which management evaluates the identity of the counterparty, the vintage of the loans sold, the amount of open repurchase requests, specific loss estimates for each open request, the current level of loan losses in similar vintages held in the residential loan portfolio, and estimated recoveries on the underlying collateral. The reserve also reflects management’s expectation of losses from loan repurchase requests for which the Company has not yet been notified. The provision recorded at the time of the loan sale is netted from the gain or loss recorded in mortgage banking activities, while any incremental provision, post loan sale, is recorded in other non-interest expense in the consolidated income statement. The following table provides a summary of activity in the reserve for loan repurchases: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Beginning balance $ 655 $ 684 $ 508 $ 674 Provision charged to expense 50 19 99 1,839 (Charge-offs/settlements, net) recoveries, net — (7) 98 (1,817) Ending balance $ 705 $ 696 $ 705 $ 696 The following table provides information for mortgage banking activities: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Residential mortgage loans held for sale: Proceeds from sale $ 172,579 $ 66,236 $ 342,747 $ 129,700 Loans sold with servicing rights retained 164,054 60,493 325,832 117,306 Net gain on sale 6,244 1,652 11,587 2,510 Ancillary fees 1,018 470 2,243 1,051 Fair value option adjustment (175) 11 355 268 Additionally, loans not originated for sale were sold approximately at carrying value for cash proceeds of $6.4 million, resulting in a gain of approximately $295 thousand, for certain commercial loans for the nine months ended September 30, 2020, and $4.0 million for certain residential loans and $16.6 million, resulting in a gain of approximately $615 thousand, for certain commercial loans for the nine months ended September 30, 2019. The Company services residential mortgage loans for other entities totaling $2.4 billion at both September 30, 2020 and December 31, 2019. The following table presents the changes in carrying value for mortgage servicing assets: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Beginning balance $ 14,926 $ 18,712 $ 17,484 $ 21,215 Additions 1,301 966 3,269 2,219 Amortization (1,616) (1,801) (4,992) (5,557) Valuation allowance (203) — (1,353) — Ending balance $ 14,408 $ 17,877 $ 14,408 $ 17,877 Loan servicing fees, net of mortgage servicing rights amortization, were $0.3 million and $0.5 million for the three months ended September 30, 2020, and $1.1 million and $1.4 million for the nine months ended September 30, 2020 and 2019, respectively, and are included as a component of loan related fees in the consolidated statement of income. Refer to Note 14: Fair Value Measurements for additional information on loans held for sale and mortgage servicing assets.

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Leases	Leasing The Company enters into leases, as lessee, primarily for office space, banking centers, and certain other operational assets. These leases are generally classified as operating leases, however, an insignificant amount are classified as finance leases. The Company's operating leases generally have lease terms for periods of 5 to 20 years with various renewal options. The Company does not have any material sub-lease agreements. The following table summarizes lessee information related to the Company’s operating ROU assets and lease liability: At September 30, 2020 (In thousands) Operating Leases Consolidated Balance Sheet Line Item Location ROU lease assets $ 146,641 Premises and equipment, net Lease liabilities 165,211 Operating lease liabilities The components of operating lease cost and other related information are as follows: At or for the three months ended September 30, At or for the nine months ended September 30, (In thousands) 2020 2019 2020 2019 Lease Cost: Operating lease costs $ 7,381 $ 7,512 $ 22,212 $ 22,384 Variable lease costs 1,297 1,292 4,217 3,613 Sublease income (141) (142) (428) (437) Total operating lease cost $ 8,537 $ 8,662 $ 26,001 $ 25,560 Other Information: Cash paid for amounts included in the measurement of lease liabilities $ 7,823 $ 7,938 $ 23,359 $ 23,349 ROU lease assets obtained in exchange for new operating lease liabilities 856 9,983 9,552 22,917 The undiscounted scheduled maturities reconciled to total operating lease liabilities are as follows: (In thousands) At September 30, 2020 Remainder of 2020 $ 5,274 2021 30,604 2022 27,099 2023 24,187 2024 21,307 Thereafter 82,710 Total operating lease liability payments 191,181 Less: Present value adjustment 25,970 Lease liabilities $ 165,211 Weighted-average remaining lease term - operating leases, in years 8.23 Weighted-average discount rate - operating leases 3.22%

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets There has been no change during 2020 in the carrying amounts for goodwill. For additional information on goodwill refer to the Company's Annual Report on Form 10-K for the year ended December 31, 2019. Other intangible assets by reportable segment consisted of the following: At September 30, 2020 At December 31, 2019 (In thousands) Gross Carrying Accumulated Net Carrying Gross Carrying Accumulated Net Carrying HSA Bank - Core deposits $ 26,625 $ 14,875 $ 11,750 $ 22,000 $ 13,073 $ 8,927 HSA Bank - Customer relationships 21,000 9,221 11,779 21,000 8,010 12,990 Total other intangible assets $ 47,625 $ 24,096 $ 23,529 $ 43,000 $ 21,083 $ 21,917 The change in gross carrying amount for core deposits resulted from the HSA division of Webster Bank completing an asset purchase of low cost, long duration, health savings account deposits, on July 30, 2020. The transaction gave rise to the recognition of a core deposit intangible asset, recorded at fair value, with an estimated useful life of 9 years. At September 30, 2020, the remaining estimated aggregate future amortization expense for other intangible assets is as follows: (In thousands) Remainder of 2020 $ 1,146 2021 4,513 2022 4,411 2023 4,315 2024 2,084 Thereafter 7,060

Deposits

Deposits	9 Months Ended
	Sep. 30, 2020
Deposit Liabilities [Abstract]
Deposits	Deposits A summary of deposits by type follows: (In thousands) At September 30, At December 31, Non-interest-bearing: Demand $ 6,136,814 $ 4,446,463 Interest-bearing: Health savings accounts 6,976,280 6,416,135 Checking 3,390,921 2,689,734 Money market 3,069,098 2,312,840 Savings 4,777,000 4,354,809 Time deposits 2,570,440 3,104,765 Total interest-bearing $ 20,783,739 $ 18,878,283 Total deposits $ 26,920,553 $ 23,324,746 Time deposits and interest-bearing checking, included in above balances, obtained through brokers $ 733,691 $ 652,151 Time deposits, included in above balance, that exceed the FDIC limit 533,180 661,334 Deposit overdrafts reclassified as loan balances 1,122 1,721 The scheduled maturities of time deposits are as follows: (In thousands) At September 30, Remainder of 2020 $ 849,021 2021 1,468,973 2022 141,760 2023 45,774 2024 22,321 Thereafter 42,591 Total time deposits $ 2,570,440

Borrowings

Borrowings	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Borrowings	Borrowings Total borrowings of $2.3 billion at September 30, 2020 and $3.5 billion at December 31, 2019 are described in detail below. The following table summarizes securities sold under agreements to repurchase and other borrowings: At September 30, At December 31, (Dollars in thousands) Amount Rate Amount Rate Securities sold under agreements to repurchase (1) : Original maturity of one year or less $ 278,122 0.19 % $ 240,431 0.19 % Original maturity of greater than one year, non-callable 200,000 0.57 200,000 1.78 Total securities sold under agreements to repurchase 478,122 0.35 440,431 0.91 Fed funds purchased 823,700 0.08 600,000 1.59 Securities sold under agreements to repurchase and other borrowings $ 1,301,822 0.18 $ 1,040,431 1.30 (1) The Company has 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. Repurchase agreements are used as a source of borrowed funds and are collateralized by U.S. Government agency mortgage-backed securities. Repurchase agreement counterparties are limited to primary dealers in government securities and commercial/municipal customers through the Corporate Treasury function. The following table provides information for FHLB advances: At September 30, 2020 At December 31, 2019 (Dollars in thousands) Amount Weighted- Amount Weighted- Maturing within 1 year $ 175,000 0.88 % $ 1,690,000 1.79 % After 1 but within 2 years 150,024 1.15 200,000 2.53 After 2 but within 3 years 169 1.73 130 — After 3 but within 4 years 50,141 1.59 229 2.95 After 4 but within 5 years 50,000 1.42 50,000 1.59 After 5 years 7,909 2.66 8,117 2.66 FHLB advances $ 433,243 1.15 $ 1,948,476 1.87 Aggregate carrying value of assets pledged as collateral $ 7,561,287 $ 7,318,748 Remaining borrowing capacity 4,506,213 2,937,644 Webster Bank is in compliance with FHLB collateral requirements for the periods presented. Eligible collateral, primarily certain residential and commercial real estate loans, has been pledged to secure FHLB advances. The following table summarizes long-term debt: (Dollars in thousands) At September 30, At December 31, 4.375% Senior fixed-rate notes due February 15, 2024 $ 150,000 $ 150,000 4.100% Senior fixed-rate notes due March 25, 2029 (1) 345,502 317,486 Junior subordinated debt Webster Statutory Trust I floating-rate notes due September 17, 2033 (2) 77,320 77,320 Total notes and subordinated debt 572,822 544,806 Discount on senior fixed-rate notes (1,247) (1,412) Debt issuance cost on senior fixed-rate notes (2,729) (3,030) Long-term debt $ 568,846 $ 540,364 (1) The Company has de-designated its fair value hedging relationship on these notes. The $45.5 million basis adjustment included in the carrying value at September 30, 2020 is being amortized over the remaining life of the notes. (2) The interest rate on Webster Statutory Trust I floating-rate notes, which varies quarterly based on 3-month London Interbank Offered Rate plus 2.95%, was 3.20% at September 30, 2020 and 4.85% at December 31, 2019.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income, Net of Tax	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Accumulated Other Comprehensive Income, Net of Tax	Accumulated Other Comprehensive Income, Net of Tax The following tables summarize the changes in accumulated other comprehensive income (loss), net of tax, by component: Three months ended September 30, 2020 Nine months ended September 30, 2020 (In thousands) Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Beginning balance $ 63,476 $ 20,649 $ (42,680) $ 41,445 $ 17,251 $ (9,184) $ (44,139) $ (36,072) OCI before reclassifications 11,766 (3,310) — 8,456 57,997 23,655 — 81,652 Amounts reclassified from AOCI — 1,398 738 2,136 (6) 4,266 2,197 6,457 Net current-period OCI 11,766 (1,912) 738 10,592 57,991 27,921 2,197 88,109 Ending balance $ 75,242 $ 18,737 $ (41,942) $ 52,037 $ 75,242 $ 18,737 $ (41,942) $ 52,037 Three months ended September 30, 2019 Nine months ended September 30, 2019 (In thousands) Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Beginning balance $ (9,406) $ (8,931) $ (47,853) $ (66,190) $ (71,374) $ (9,313) $ (49,965) $ (130,652) OCI/OCL before reclassifications 24,304 2,216 — 26,520 86,272 507 — 86,779 Amounts reclassified from AOCL — 1,387 1,049 2,436 — 3,478 3,161 6,639 Net current-period OCI 24,304 3,603 1,049 28,956 86,272 3,985 3,161 93,418 Ending balance $ 14,898 $ (5,328) $ (46,804) $ (37,234) $ 14,898 $ (5,328) $ (46,804) $ (37,234) The following table provides information for the items reclassified from AOCI/AOCL: (In thousands) Three months ended September 30, Nine months ended September 30, Associated Line Item in the Condensed Consolidated Statements of Income AOCI/AOCL Components 2020 2019 2020 2019 Securities available-for-sale: Unrealized gains on investment securities $ — $ — $ 8 $ — Gain on sale of investment securities, net Tax expense — — (2) — Income tax expense Net of tax $ — $ — $ 6 $ — Derivative instruments: Premium amortization and hedge terminations $ (967) $ (1,375) $ (3,228) $ (4,174) Interest expense Premium amortization (926) (515) (2,548) (527) Interest income Tax benefit 495 503 1,510 1,223 Income tax expense Net of tax $ (1,398) $ (1,387) $ (4,266) $ (3,478) Defined benefit pension and other postretirement benefit plans: Amortization of net loss $ (1,002) $ (1,421) $ (2,982) $ (4,280) Other non-interest expense Tax benefit 264 372 785 1,119 Income tax expense Net of tax $ (738) $ (1,049) $ (2,197) $ (3,161)

Regulatory Matters

Regulatory Matters	9 Months Ended
	Sep. 30, 2020
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Regulatory Matters	Regulatory Matters Capital Requirements Webster Financial Corporation is subject to regulatory capital requirements administered by the Federal Reserve System, while Webster Bank is subject to regulatory capital requirements administered by the OCC. Regulatory authorities can initiate certain mandatory actions if Webster Financial Corporation or Webster Bank fail to meet minimum capital requirements, which could have a direct material effect on the Company’s financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, both Webster Financial Corporation and Webster Bank must meet specific capital guidelines that involve quantitative measures of assets, liabilities, and certain off-balance sheet items calculated under regulatory accounting practices. These quantitative measures require minimum amounts and ratios to ensure capital adequacy. Total risk-based capital is comprised of three categories as defined by Basel III capital rules: common equity Tier 1 capital (CET1 capital), Tier 1 capital, and Tier 2 capital. CET1 capital includes common shareholders' equity, less deductions for goodwill, other intangibles, and certain deferred tax adjustments. For purposes of CET1 capital, common shareholders' equity excludes AOCI/AOCL components as permitted by the opt-out election taken by Webster upon adoption of Basel III. Tier 1 capital is comprised of CET1 capital plus non-cumulative perpetual preferred stock, while Tier 2 capital includes qualifying subordinated debt and qualifying allowance for credit losses, that together equal total capital. The following table provides information on the capital ratios for Webster Financial Corporation and Webster Bank: At September 30, 2020 Actual (1) Minimum Requirement Well Capitalized (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 risk-based capital $ 2,519,589 11.23 % $ 1,009,651 4.5 % $ 1,458,385 6.5 % Total risk-based capital 3,022,511 13.47 1,794,935 8.0 2,243,669 10.0 Tier 1 risk-based capital 2,664,626 11.88 1,346,201 6.0 1,794,935 8.0 Tier 1 leverage capital 2,664,626 8.24 1,293,186 4.0 1,616,482 5.0 Webster Bank CET1 risk-based capital $ 2,744,235 12.24 % $ 1,009,277 4.5 % $ 1,457,845 6.5 % Total risk-based capital 3,024,694 13.49 1,794,270 8.0 2,242,838 10.0 Tier 1 risk-based capital 2,744,235 12.24 1,345,703 6.0 1,794,270 8.0 Tier 1 leverage capital 2,744,235 8.49 1,292,763 4.0 1,615,954 5.0 At December 31, 2019 Actual Minimum Requirement Well Capitalized (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 risk-based capital $ 2,516,361 11.56 % $ 979,739 4.5 % $ 1,415,179 6.5 % Total risk-based capital 2,950,181 13.55 1,741,758 8.0 2,177,198 10.0 Tier 1 risk-based capital 2,661,398 12.22 1,306,319 6.0 1,741,758 8.0 Tier 1 leverage capital 2,661,398 8.96 1,188,507 4.0 1,485,634 5.0 Webster Bank CET1 risk-based capital $ 2,527,645 11.61 % $ 979,497 4.5 % $ 1,414,829 6.5 % Total risk-based capital 2,739,108 12.58 1,741,328 8.0 2,176,660 10.0 Tier 1 risk-based capital 2,527,645 11.61 1,305,996 6.0 1,741,328 8.0 Tier 1 leverage capital 2,527,645 8.51 1,187,953 4.0 1,484,941 5.0 (1) In accordance with regulatory capital rules, the Company elected an option to delay the estimated impact of CECL on its regulatory capital over a two-year deferral and subsequent three-year transition period ending December 31, 2024. As a result, capital ratios and amounts as of September 30, 2020 exclude the impact of the increased allowance for credit losses on loans, held-to-maturity debt securities, and unfunded loan commitments attributed to the adoption of CECL, adjusted for an approximation of the after-tax provision for credit losses attributable to CECL relative to the incurred loss methodology during the deferral period. Dividend Restrictions. Webster Financial Corporation is dependent upon dividends from Webster Bank to provide funds for its cash requirements, including payments of dividends to shareholders. 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 would exceed the net income for that year combined with the undistributed net income for the preceding two years. Webster Bank paid no dividends to Webster Financial Corporation during the nine months ended September 30, 2020 compared to $170 million during the nine months ended September 30, 2019. Cash Restrictions. Webster Bank is required by Federal Reserve System regulations to hold cash reserve balances on hand or with a Federal Reserve Bank. To address liquidity concerns due to COVID-19 the Federal Reserve reset the requirement to zero, effective March 26, 2020. The reserve requirement ratio is subject to adjustment as conditions warrant.

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share Reconciliation of the calculation of basic and diluted earnings per common share follows: Three months ended September 30, Nine months ended September 30, (In thousands, except per share data) 2020 2019 2020 2019 Earnings for basic and diluted earnings per common share: Net income $ 69,281 $ 93,865 $ 160,577 $ 292,250 Less: Preferred stock dividends 1,968 1,968 5,906 5,906 Net income available to common shareholders 67,313 91,897 154,671 286,344 Less: Earnings applicable to participating securities (1) 423 455 913 1,425 Earnings applicable to common shareholders $ 66,890 $ 91,442 $ 153,758 $ 284,919 Shares: Weighted-average common shares outstanding - basic 89,630 91,559 90,076 91,554 Effect of dilutive securities 108 315 159 329 Weighted-average common shares outstanding - diluted 89,738 91,874 90,235 91,883 Earnings per common share (1) : Basic $ 0.75 $ 1.00 $ 1.71 $ 3.11 Diluted 0.75 1.00 1.70 3.10 (1) Earnings per common share amounts under the two-class method, for nonvested time-based restricted shares with nonforfeitable dividends and dividend rights, are determined the same as the presentation above. Dilutive Securities The Company maintains stock compensation plans under which restricted stock, restricted stock units, non-qualified stock options, incentive stock options, or stock appreciation rights may be granted to employees and directors. The effect of dilutive securities for the periods presented is primarily the result of outstanding stock options, as well as non-participating restricted stock. Potential common shares from non-participating restricted stock, of 96 thousand and 44 thousand for the three months ended September 30, 2020 and 2019, respectively, and 125 thousand and 69 thousand for the nine months ended September 30, 2020 and 2019, respectively, are excluded from the effect of dilutive securities because they would have been anti-dilutive under the treasury stock method.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments Derivative Positions and Offsetting Derivatives Designated in Hedge Relationships . Interest rate swaps allow the Company to change the fixed or variable nature of an interest rate without the exchange of the underlying notional amount. Certain pay fixed/receive variable interest rate swaps are designated as cash flow hedges to effectively convert variable-rate debt into fixed-rate debt, while certain receive fixed/pay variable interest rate swaps are designated as fair value hedges to effectively convert fixed-rate long-term debt into variable-rate debt. Certain purchased options are designated as cash flow hedges. Purchased options allow the Company to limit the potential adverse impact of variable interest rates by establishing a cap or a floor rate in exchange for an upfront premium. The purchased options designated as cash flow hedges represent interest rate caps where payment is received from the counterparty if interest rates rise above the cap rate and interest rate floors where payment is received from the counterparty when interest rates fall below the floor rate. Derivatives Not Designated in Hedge Relationships. The Company also enters into other derivative transactions to manage economic risks but does not designate the instruments in hedge relationships. Further, the Company enters into derivative contracts to accommodate customer needs. Derivative contracts with customers are offset with dealer counterparty transactions structured with matching terms to ensure minimal impact on earnings. The following table presents the notional amounts and fair values of derivative positions: At September 30, 2020 At December 31, 2019 Asset Derivatives Liability Derivatives Asset Derivatives Liability Derivatives (In thousands) Notional Fair Notional Fair Notional Fair Notional Fair Designated as hedging instruments: Interest rate derivatives (1) $ 1,150,000 $ 44,114 $ 25,000 $ 145 $ 1,225,000 $ 11,855 $ 300,000 $ 3,153 Not designated as hedging instruments: Interest rate derivatives (1) 4,642,373 341,275 4,505,792 17,212 4,869,139 133,455 4,090,522 9,732 Mortgage banking derivatives (2) 105,605 2,717 — — 27,873 329 57,000 110 Other (3) 111,089 333 351,288 890 76,544 398 275,279 818 Total not designated as hedging instruments 4,859,067 344,325 4,857,080 18,102 4,973,556 134,182 4,422,801 10,660 Gross derivative instruments, before netting $ 6,009,067 388,439 $ 4,882,080 18,247 $ 6,198,556 146,037 $ 4,722,801 13,813 Less: Master netting agreements 12,390 12,390 4,779 4,779 Cash collateral 32,159 5,085 8,100 1,871 Total derivative instruments, after netting $ 343,890 $ 772 $ 133,158 $ 7,163 (1) Balances related to Chicago Mercantile Exchange (CME) are presented as a single unit of account. In accordance with its rule book, CME legally characterizes variation margin payments as settlement of derivatives rather than collateral against derivative positions. Notional amounts of interest rate swaps cleared through CME include $60.1 million and $1.1 billion for asset derivatives and $3.4 billion and $2.6 billion for liability derivatives at September 30, 2020 and December 31, 2019, respectively. The related fair values approximate zero. (2) Notional amounts related to residential loans exclude approved floating rate commitments of $10.8 million at September 30, 2020. (3) Other derivatives include foreign currency forward contracts related to lending arrangements and customer hedging activity, a Visa equity swap transaction, and risk participation agreements (RPAs). Notional amounts of RPAs include $95.4 million and $65.7 million for asset derivatives and $317.8 million and $223.4 million for liability derivatives at September 30, 2020 and December 31, 2019, respectively, that have insignificant related fair values. The following table presents fair value positions transitioned from gross to net upon applying counterparty netting agreements: At September 30, 2020 (In thousands) Gross Offset Amount Net Amount on Balance Sheet Amounts Not Offset Net Amounts Asset derivatives $ 44,549 $ 44,549 $ — $ 196 $ 196 Liability derivatives 17,568 17,475 93 1,041 1,134 At December 31, 2019 (In thousands) Gross Offset Amount Net Amount on Balance Sheet Amounts Not Offset Net Amounts Asset derivatives $ 13,012 $ 12,879 $ 133 $ 299 $ 432 Liability derivatives 6,710 6,650 60 329 389 Derivative Activity The following tables present the income statement effect of derivatives designated as hedges and additional information related to a fair value hedging adjustment: Recognized In Three months ended September 30, Nine months ended September 30, (In thousands) Net Interest Income 2020 2019 2020 2019 Fair value hedges: (1) Recognized on derivatives Long-term debt $ — $ 10,624 $ 30,693 $ 26,436 Recognized on hedged items Long-term debt — (10,624) (30,693) (26,436) Net recognized on fair value hedges $ — $ — $ — $ — Cash flow hedges: Interest rate derivatives Long-term debt $ 1,152 $ 1,095 $ 3,501 $ 3,028 Interest rate derivatives Interest and fees on loans and leases (2,657) 515 (3,754) 527 Net recognized on cash flow hedges $ (1,505) $ 1,610 $ (253) $ 3,555 Consolidated Balance Sheet Line Item in Which Hedged Item is Located Carrying Amount of Hedged Item Cumulative Amount of Fair Value Hedging Adjustment Included in Carrying Amount (1) (In thousands) At September 30, At December 31, At September 30, At December 31, Long-term debt $ 345,502 $ 317,486 $ 45,502 $ 17,486 (1) The Company has de-designated its fair value hedging relationship on the long-term debt, which resulted in a $48.2 million basis adjustment that is being amortized over the remaining life of the notes through interest expense. The following table presents the effect on the income statement for derivatives not designated as hedging instruments: Recognized In Three months ended September 30, Nine months ended September 30, (In thousands) Non-interest Income 2020 2019 2020 2019 Interest rate derivatives Other income $ 3,824 $ 784 $ 7,227 $ 5,906 Mortgage banking derivatives Mortgage banking activities 872 347 2,498 96 Other Other income (1,229) 1,679 (332) 1,603 Total not designated as hedging instruments $ 3,467 $ 2,810 $ 9,393 $ 7,605 Purchased options designated as cash flow hedges exclude time-value premiums from the assessment of hedge effectiveness. Time-value premiums are amortized on a straight-line basis. At September 30, 2020, the remaining unamortized balance of time-value premiums was $10.0 million. Over the next twelve months, an estimated $8.1 million decrease to interest expense will be reclassified from AOCI/AOCL relating to cash flow hedges, and an estimated $1.9 million increase to interest expense will be reclassified from AOCI/AOCL relating to hedge terminations. At September 30, 2020, the remaining unamortized loss on terminated cash flow hedges is $3.1 million. The maximum length of time over which forecasted transactions are hedged is 4 years. Additional information about cash flow hedge activity impacting AOCI/AOCL and the related amounts reclassified to interest expense is provided in Note 10: Accumulated Other Comprehensive Income, Net of Tax. Information about the valuation methods used to measure the fair value of derivatives is provided in Note 14: Fair Value Measurements. Derivative Exposure The Company had approximately $349.5 million in net margin posted with financial counterparties or the derivative clearing organization at September 30, 2020, which is primarily comprised of $82.8 million in initial margin collateral posted at CME and $294.6 million in CME variation margin posted. At September 30, 2020, $33.2 million of cash collateral received is included in cash and due from banks on the consolidated balance sheet and is considered restricted in nature. Webster regularly evaluates the credit risk of its derivative customers, taking into account the likelihood of default, net exposures, and remaining contractual life, among other related factors. Credit risk exposure is mitigated as transactions with customers are generally secured by the same collateral of the underlying transactions being hedged. Current net credit exposure relating to interest rate derivatives with Webster Bank customers was $346.1 million at September 30, 2020. In addition, the Company monitors potential future exposure, representing its best estimate of exposure to remaining contractual maturity. The potential future exposure relating to interest rate derivatives with Webster Bank customers totaled $40.0 million at September 30, 2020. The Company has incorporated a credit valuation adjustment (CVA) to reflect nonperformance risk in the fair value measurement of its derivatives. The CVA was $4.2 million as of September 30, 2020. Various factors impact changes in the CVA over time, including changes in the credit spreads of the parties to the contracts, as well as changes in market rates and volatilities, which affect the total expected exposure of the derivative instruments.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value is 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 best determined using quoted market prices. However, in many instances, quoted market prices are not available. In such instances, fair values are determined using appropriate valuation techniques. Various assumptions and observable inputs must be relied upon in applying these techniques. Accordingly, categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. As such, the fair value estimates may not be realized in an immediate transfer of the respective asset or liability. Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the entire holdings or any part of a particular financial instrument. Fair value estimates are based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments, and other factors. These factors are subjective in nature and involve uncertainties and matters of significant judgment and, therefore, cannot be determined with precision. Changes in assumptions could significantly affect the estimates. Fair Value Hierarchy The three levels within the fair value hierarchy are as follows: • Level 1: Valuation is based upon unadjusted quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. • Level 2: Fair value is calculated using significant inputs other than quoted market prices that are directly or indirectly observable for the asset or liability. The valuation may rely on 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 (such as interest rates, rate volatility, prepayment speeds, credit ratings,) or inputs that are derived principally or corroborated by market data, by correlation, or other means. • Level 3: Inputs for determining the fair value of the respective assets or liabilities are not observable. Level 3 valuations are reliant upon pricing models and techniques that require significant management judgment or estimation. Assets and Liabilities Measured at Fair Value on a Recurring Basis Available-for-Sale Investment Securities . When quoted prices are available in an active market, the Company classifies available-for-sale investment securities within Level 1 of the valuation hierarchy. U.S. Treasury Bills 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. Such 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 respective terms and conditions for debt instruments. Management maintains procedures to monitor the pricing service's results and has an established process to challenge their valuations, or methodologies, that appear unusual or unexpected. Available-for-Sale investment securities which include Agency CMO, Agency MBS, Agency CMBS, CMBS, CLO, and corporate debt, are classified within Level 2 of the fair value hierarchy. Derivative Instruments . Foreign exchange contracts are valued based on unadjusted quoted prices in active markets and classified within Level 1 of the fair value hierarchy. 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 validated against valuations performed by independent third parties and are classified within Level 2 of the fair value hierarchy. Webster evaluates the credit risk of its counterparties to determine the CVA by considering factors such as the likelihood of default by the counterparty, its net exposure, remaining contractual life, as well as the collateral securing the position. While the Company has determined that the majority of the inputs used to value its derivative financial instruments fall within Level 2 of the fair value hierarchy, the CVA utilizes Level 3 inputs. The Company has assessed the significance of the impact of the CVA on the overall valuation of its derivative positions as of September 30, 2020, and has determined that the CVA is not significant to the overall valuation of its derivative financial instruments. Therefore, the Company has determined that the fair value measures of its derivative financial instruments in their entirety are classified within Level 2 of the fair value hierarchy. Mortgage Banking Derivatives . Forward sales of mortgage loans and mortgage-backed securities are utilized by the Company in its efforts to manage 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 the period from commitment date to closing date, the Company is subject to the risk that market rates of interest may change. If market rates rise, investors generally will pay less to purchase such loans resulting in a reduction in the gain on sale of the loans or, possibly, a loss. In an effort to mitigate such risk, forward delivery sales commitments are established, under which the Company agrees to 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 and, therefore, classified within Level 2 of the fair value hierarchy. Originated Loans Held For Sale . Residential mortgage loans typically are classified as held for sale upon origination based on management's intent to sell such loans. The Company generally records residential mortgage loans held for sale under the fair value option of Accounting Standards Codification (ASC) Topic 825 "Financial Instruments." Electing to measure originated loans held for sale at fair value reduces certain timing differences and better matches changes in the value of these assets with changes in the value of the derivatives used as an economic hedge on these assets. The fair value of residential mortgage loans held for sale is based on quoted market prices of similar loans sold in conjunction with securitization transactions. Accordingly, such loans are classified within Level 2 of the fair value hierarchy. The following table compares the fair value to unpaid principal balance of assets accounted for under the fair value option: At September 30, 2020 At December 31, 2019 (In thousands) Fair Value Unpaid Principal Balance Difference Fair Value Unpaid Principal Balance Difference Originated loans held for sale $ 29,018 $ 28,433 $ 585 $ 35,750 $ 35,186 $ 564 Investments Held in Rabbi Trust. Investments held in the Rabbi Trust primarily include mutual funds that invest in equity and fixed income securities. Shares of mutual funds are valued based on net asset value, which represents quoted market prices for the underlying shares held in the mutual funds. Therefore, investments held in the Rabbi Trust are classified within Level 1 of the fair value hierarchy. The Company has elected to measure the investments held in the Rabbi Trust at fair value. The cost basis of the investments held in the Rabbi Trust is $1.6 million at September 30, 2020. Alternative Investments. Equity investments have a readily determinable fair value when quoted prices are available in an active market. Accordingly, such alternative investments are classified within Level 1 of the fair value hierarchy. Equity investments that do not have a readily available fair value may qualify for net asset value (NAV) practical expedient 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. Alternative investments recorded at NAV are not classified within the fair value hierarchy. At September 30, 2020, these alternative investments had a remaining unfunded commitment of $25.0 million. Summaries of the fair values of assets and liabilities measured at fair value on a recurring basis are as follows: At September 30, 2020 (In thousands) Level 1 Level 2 Level 3 Total Financial assets held at fair value: Agency CMO $ — $ 173,354 $ — $ 173,354 Agency MBS — 1,527,270 — 1,527,270 Agency CMBS — 1,051,754 — 1,051,754 CMBS — 455,025 — 455,025 CLO — 84,361 — 84,361 Corporate debt — 12,453 — 12,453 Total available-for-sale investment securities — 3,304,217 — 3,304,217 Gross derivative instruments, before netting (1) 209 388,230 — 388,439 Originated loans held for sale — 29,018 — 29,018 Investments held in Rabbi Trust 4,657 — — 4,657 Alternative investments (2) — — — 8,238 Total financial assets held at fair value $ 4,866 $ 3,721,465 $ — $ 3,734,569 Financial liabilities held at fair value: Gross derivative instruments, before netting (1) $ 229 $ 18,018 $ — $ 18,247 At December 31, 2019 (In thousands) Level 1 Level 2 Level 3 Total Financial assets held at fair value: Agency CMO $ — $ 185,801 $ — $ 185,801 Agency MBS — 1,612,164 — 1,612,164 Agency CMBS — 581,552 — 581,552 CMBS — 431,871 — 431,871 CLO — 92,205 — 92,205 Corporate debt — 22,240 — 22,240 Total available-for-sale investment securities — 2,925,833 — 2,925,833 Gross derivative instruments, before netting (1) 328 145,709 — 146,037 Originated loans held for sale — 35,750 — 35,750 Investments held in Rabbi Trust 4,780 — — 4,780 Alternative investments (2) — — — 4,331 Total financial assets held at fair value $ 5,108 $ 3,107,292 $ — $ 3,116,731 Financial liabilities held at fair value: Gross derivative instruments, before netting (1) $ 611 $ 13,202 $ — $ 13,813 (1) For information relating to the impact of netting derivative assets and derivative liabilities as well as the impact from offsetting cash collateral paid to the same derivative counterparties see Note 13: Derivative Financial Instruments. (2) 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 Certain assets are measured at fair value on a non-recurring basis; that is, the assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances, for example, when there is evidence of impairment. At September 30, 2020, no significant assets classified within Level 3 were identified and measured under this basis. The following is a description of valuation methodologies used for assets measured 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 accounted for at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. These alternative investments are investments in non-public entities that generally cannot be redeemed since the investment is distributed as the underlying equity is liquidated. Accordingly, these alternative investments are classified within Level 2 of the fair value hierarchy. The carrying amount of these alternative investments was $14.5 million at September 30, 2020. No reductions for impairments, or adjustments due to observable price changes, was identified during the nine months ended September 30, 2020. Transferred Loans Held For Sale. Certain loans are transferred to loans held for sale once a decision has been made to sell such loans. These loans are accounted for at the lower of cost or fair value and are considered to be recognized at fair value when they are recorded at below cost. This activity primarily consists of commercial loans with observable inputs and is classified within Level 2. On the occasion that these loans should include adjustments for changes in loan characteristics using unobservable inputs, the loans would be classified within Level 3. Collateral Dependent Loans and Leases. Loans and leases for which the payment is expected to be provided solely by the value of the underlying collateral are considered collateral dependent and are valued based on the estimated fair value of such collateral, less estimated cost to sell, using customized discounting criteria. Accordingly, such collateral dependent loans and leases are classified within Level 3 of the fair value hierarchy. Other Real Estate Owned and Repossessed Assets. The total book value of OREO and repossessed assets was $4.7 million at September 30, 2020. OREO and repossessed assets are accounted for at the lower of cost or fair value and are considered to be recognized at fair value when recorded below cost. The fair value of OREO is based on independent appraisals or internal valuation methods, less estimated selling costs. The valuation may consider available pricing guides, auction results, and price opinions. Certain assets require assumptions about factors that are not observable in an active market in the determination of fair value; as such, OREO and repossessed assets are classified within Level 3 of the fair value hierarchy. In addition, the amortized cost of consumer loans secured by residential real estate property that are in process of foreclosure amounted to $12.5 million at September 30, 2020. Fair Value of Financial Instruments and Servicing Assets The Company is required to disclose the estimated fair value of financial instruments for which it is practicable to estimate fair value, as well as servicing assets. The following is a description of valuation methodologies used for those assets and liabilities. Cash, Due from Banks, and Interest-bearing Deposits . The carrying amount of cash, due from banks, and interest-bearing deposits is used to approximate fair value, given the short time frame to maturity and, as such, these assets do not present unanticipated credit concerns. Cash, due from banks, and interest-bearing deposits are classified within Level 1 of the fair value hierarchy. Held-to-Maturity Investment Securities . When quoted market prices are not available, the Company employs an independent pricing service that utilizes matrix pricing to calculate fair value. Such 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 respective terms and conditions for debt instruments. Management maintains procedures to monitor the pricing service's results and has an established process to challenge their valuations, or methodologies, that appear unusual or unexpected. Held-to-Maturity investment securities, which include Agency CMO, Agency MBS, Agency CMBS, CMBS, and municipal bonds and notes, are classified within Level 2 of the fair value hierarchy. Loans and Leases, net . The estimated fair value of loans and leases held for investment is calculated using a discounted cash flow method, using future prepayments and market interest rates inclusive of an illiquidity premium for comparable loans and leases. The associated cash flows are adjusted for credit and other potential losses. Fair value for collateral dependent loans and leases is estimated using the net present value of the expected cash flows. Loans and leases are classified within Level 3 of the fair value hierarchy. Deposit Liabilities . The fair value of demand deposits, savings accounts, and certain money market deposits is 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 a fixed-maturity certificate of deposit is estimated using the rates currently offered for deposits of 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 is the carrying value. Fair value for all other balances are estimated using discounted cash flow analysis based on current market rates 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 technique. Discount rates are matched with the time period of the expected cash flow and are adjusted, as appropriate, to reflect credit risk. FHLB advances and long-term debt are classified within Level 2 of the fair value hierarchy. Mortgage Servicing Assets . Mortgage servicing assets are initially recorded at fair value and subsequently measured under the amortization method. 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; as such, the primary risk inherent in valuing mortgage servicing assets is the impact of fluctuating interest rates on the servicing revenue stream. Mortgage servicing assets are reviewed quarterly and held at the lower of the carrying amount or fair value. Fair value adjustments, if any, are included as a component of loan related fees in the consolidated statement of income. During the nine months ended September 30, 2020, the Company recorded a $1.4 million valuation allowance. Mortgage servicing assets are classified within Level 3 of the fair value hierarchy. The estimated fair value of selected financial instruments and servicing assets are as follows: At September 30, 2020 At December 31, 2019 (In thousands) Carrying Fair Carrying Fair Assets: Level 2 Held-to-maturity investment securities $ 5,723,128 $ 6,006,416 $ 5,293,918 $ 5,380,653 Level 3 Loans and leases, net 21,482,212 21,695,557 19,827,890 19,961,632 Mortgage servicing assets 14,408 15,559 17,484 33,250 Liabilities: Level 2 Deposit liabilities $ 24,350,113 $ 24,350,113 $ 20,219,981 $ 20,219,981 Time deposits 2,570,440 2,580,279 3,104,765 3,102,316 Securities sold under agreements to repurchase and other borrowings 1,301,822 1,305,029 1,040,431 1,041,042 FHLB advances 433,243 442,724 1,948,476 1,950,035 Long-term debt (1) 568,846 525,170 540,364 555,775 (1) Adjustments to the carrying amount of long-term debt for basis adjustment and unamortized discount and debt issuance cost on senior fixed-rate notes are not included for determination of fair value Refer to Note 9: Borrowings for additional information.

Retirement Benefit Plans

Retirement Benefit Plans	9 Months Ended
	Sep. 30, 2020
Retirement Benefits [Abstract]
Retirement Benefit Plans	Retirement Benefit Plans Defined benefit pension and other postretirement benefits The following table summarizes the components of net periodic benefit cost: Three months ended September 30, 2020 2019 (In thousands) Pension Plan SERP Other Benefits Pension Plan SERP Other Benefits Interest cost on benefit obligations $ 1,531 $ 12 $ 9 $ 2,001 $ 16 $ 22 Expected return on plan assets (3,380) — — (2,815) — — Recognized net loss 1,036 5 (38) 1,420 4 (2) Net periodic benefit cost $ (813) $ 17 $ (29) $ 606 $ 20 $ 20 Nine months ended September 30, 2020 2019 (In thousands) Pension Plan SERP Other Benefits Pension Plan SERP Other Benefits Interest cost on benefit obligations $ 4,881 $ 35 $ 34 $ 5,956 $ 48 $ 64 Expected return on plan assets (10,140) — — (8,445) — — Recognized net loss 3,021 17 (55) 4,280 11 (10) Net periodic benefit cost $ (2,238) $ 52 $ (21) $ 1,791 $ 59 $ 54 The components of net periodic benefit cost, other than service cost, are included within other expense reflected in non-interest expense in the consolidated income statement. The weighted-average expected long-term rate of return is 5.75%.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting Webster’s operations are organized into three reportable segments that represent its primary businesses - Commercial Banking, HSA Bank, and Community Banking. These segments reflect how executive management responsibilities are assigned, the type of customer served, how products and services are provided, and how discrete financial information is currently evaluated. Certain Corporate Treasury activities, along with the amounts required to reconcile profitability metrics to amounts reported in accordance with GAAP, are included in the Corporate and Reconciling category. Description of Segment Reporting Methodology Webster uses an internal profitability reporting system to generate information by operating segment, which is based on a series of management estimates for funds transfer pricing, 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 reported results of any operating segment do not affect the consolidated financial position or results of operations of Webster as a whole. The full profitability measurement reports, which are prepared for each operating segment, reflect non-GAAP reporting methodologies. The differences between full profitability and GAAP results are reconciled in the Corporate and Reconciling category. Webster allocates interest income and interest expense to each business, while any mismatch associated with the matched maturity funding concept called Funds Transfer Pricing (FTP) is absorbed in corporate treasury activities. The allocation process considers the specific interest rate risk and liquidity risk of financial instruments and other assets and liabilities in each line of business. The matched maturity funding concept considers the origination date and the earlier of the maturity date or the repricing date of a financial instrument to assign a FTP rate for loans and deposits originated each day. Loans are assigned an FTP rate for funds used and deposits are assigned an FTP rate for funds provided. Beginning in 2020, Webster refined the FTP calculation to reflect the allocation of capital credit to net interest income to better align segment results with key measurements used to review segment performance. Prior period net interest income and income tax expense were revised to reflect this change. Webster allocates a majority of non-interest expense to each reportable segment using a full-absorption costing process. Costs, including corporate overhead, are analyzed, pooled by process, and assigned to the appropriate reportable segment. The results of funds transfer pricing and allocations for non-interest expense, as well as non-interest income produces pre-tax, pre-provision net revenue, under which basis the segments are reviewed by executive management. Webster also allocates the provision for credit losses to each segment based on management's estimate of the inherent loss content in each of the specific loan and lease portfolios. Allowance for credit losses on loans and leases is included in total assets within the Corporate and Reconciling category. The following table presents total assets for Webster's reportable segments and the Corporate and Reconciling category: (In thousands) Commercial HSA Community Corporate and Consolidated At September 30, 2020 $ 12,666,764 $ 83,104 $ 10,039,505 $ 10,205,070 $ 32,994,443 At December 31, 2019 11,541,803 80,176 9,348,727 9,418,638 30,389,344 The following tables present the operating results, including all appropriate allocations, for Webster’s reportable segments and the Corporate and Reconciling category: Three months ended September 30, 2020 (In thousands) Commercial HSA Community Banking Corporate and Consolidated Net interest income $ 107,417 $ 39,861 $ 108,218 $ (36,240) $ 219,256 Non-interest income 13,099 27,235 28,970 5,756 75,060 Non-interest expense 47,610 34,789 98,991 2,606 183,996 Pre-tax, pre-provision net revenue 72,906 32,307 38,197 (33,090) 110,320 Provision for credit losses 30,793 — (8,040) (3) 22,750 Income before income tax expense 42,113 32,307 46,237 (33,087) 87,570 Income tax expense 10,314 8,626 9,155 (9,806) 18,289 Net income $ 31,799 $ 23,681 $ 37,082 $ (23,281) $ 69,281 Three months ended September 30, 2019 (In thousands) Commercial HSA Community Banking Corporate and Consolidated Net interest income $ 104,549 $ 43,581 $ 104,613 $ (12,204) $ 240,539 Non-interest income 13,987 23,526 28,115 4,303 69,931 Non-interest expense 45,261 32,918 99,835 1,880 179,894 Pre-tax, pre-provision net revenue 73,275 34,189 32,893 (9,781) 130,576 Provision for credit losses 9,312 — 1,988 — 11,300 Income before income tax expense 63,963 34,189 30,905 (9,781) 119,276 Income tax expense 15,863 9,060 6,552 (6,064) 25,411 Net income $ 48,100 $ 25,129 $ 24,353 $ (3,717) $ 93,865 Nine months ended September 30, 2020 (In thousands) Commercial HSA Community Banking Corporate and Consolidated Net interest income $ 311,595 $ 121,868 $ 312,558 $ (71,557) $ 674,464 Non-interest income 41,063 76,721 79,995 10,735 208,514 Non-interest expense 138,848 105,887 291,644 3,037 $ 539,416 Pre-tax, pre-provision net revenue 213,810 $ 92,702 100,909 (63,859) 343,562 Provision for credit losses 131,876 — 6,965 (91) 138,750 Income before income tax expense 81,934 92,702 93,944 (63,768) 204,812 Income tax expense 20,066 24,751 18,601 (19,183) 44,235 Net income $ 61,868 $ 67,951 $ 75,343 $ (44,585) $ 160,577 Nine months ended September 30, 2019 (In thousands) Commercial HSA Community Corporate and Consolidated Net interest income $ 303,107 $ 130,692 $ 318,741 $ (28,663) $ 723,877 Non-interest income 42,643 74,082 81,172 16,499 214,396 Non-interest expense 136,075 100,693 291,076 8,376 536,220 Pre-tax, pre-provision net revenue 209,675 104,081 108,837 (20,540) 402,053 Provision for credit losses 23,294 — 8,506 — 31,800 Income before income tax expense 186,381 104,081 100,331 (20,540) 370,253 Income tax expense 46,224 27,582 21,269 (17,072) 78,003 Net income $ 140,157 $ 76,499 $ 79,062 $ (3,468) $ 292,250

Revenue from Contracts with Cus

Revenue from Contracts with Customers	9 Months Ended
	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers The following tables present revenues within the scope of ASC 606, Revenue from Contracts with Customers and the net amount of other sources of non-interest income that is within the scope of other GAAP topics: Three months ended September 30, 2020 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 2,883 $ 23,667 $ 12,704 $ 24 $ 39,278 Wealth and investment services 2,669 — 5,565 21 8,255 Other — 3,568 526 — 4,094 Revenue from contracts with customers 5,552 27,235 18,795 45 51,627 Other sources of non-interest income 7,547 — 10,175 5,711 23,433 Total non-interest income $ 13,099 $ 27,235 $ 28,970 $ 5,756 $ 75,060 Three months ended September 30, 2019 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 2,987 $ 22,264 $ 16,047 $ 112 $ 41,410 Wealth and investment services 2,650 — 5,855 (9) 8,496 Other — 1,262 650 — 1,912 Revenue from contracts with customers 5,637 23,526 22,552 103 51,818 Other sources of non-interest income 8,350 — 5,563 4,200 18,113 Total non-interest income $ 13,987 $ 23,526 $ 28,115 $ 4,303 $ 69,931 Nine months ended September 30, 2020 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 8,645 $ 70,250 $ 38,784 $ 8 $ 117,687 Wealth and investment services 7,784 — 16,336 (24) 24,096 Other — 6,471 1,583 — 8,054 Revenue from contracts with customers 16,429 76,721 56,703 (16) 149,837 Other sources of non-interest income 24,634 — 23,292 10,751 58,677 Total non-interest income $ 41,063 $ 76,721 $ 79,995 $ 10,735 $ 208,514 Nine months ended September 30, 2019 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 9,108 $ 70,496 $ 47,701 $ 247 $ 127,552 Wealth and investment services 7,676 — 16,806 (26) 24,456 Other — 3,586 1,855 — 5,441 Revenue from contracts with customers 16,784 74,082 66,362 221 157,449 Other sources of non-interest income 25,859 — 14,810 16,278 56,947 Total non-interest income $ 42,643 $ 74,082 $ 81,172 $ 16,499 $ 214,396 The major types of revenue streams that are within the scope of ASC 606 are described below: Deposit service fees, predominately consist of fees earned from deposit accounts and interchange fees. Fees earned from deposit accounts relate to event-driven services and periodic account maintenance activities. Webster's obligations for event-driven services are satisfied at the time the service is delivered, while the obligations for maintenance services is satisfied monthly. Interchange fees are assessed as the performance obligation is satisfied, which is the point in time that the card transaction is authorized. Wealth and investment services, consists of fees earned from investment and securities-related services, trust and other related services. Obligations for wealth and investment services are generally satisfied over time through a time-based measurement of progress, while certain obligations may be satisfied at points in time for activities that are transactional in nature. These disaggregated amounts are reconciled to non-interest income as presented in Note 16: Segment Reporting. Contracts with customers have not generated significant contract assets and liabilities.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Credit-Related Financial Instruments The Company offers credit-related financial instruments in the normal course of business to meet certain financing needs of its customers, that involve off-balance sheet risk. These transactions may include an unused commitment to extend credit, standby letter of credit, or commercial letter of credit. Such transactions involve, to varying degrees, elements of credit risk. Commitments to Extend Credit . The Company makes commitments under various terms to lend funds to customers at a future point in time. These commitments include revolving credit arrangements, term loan commitments, and short-term borrowing agreements. Most of these loans have fixed expiration dates or other termination clauses where a fee may be required. Since commitments routinely expire without being funded, or after required availability of collateral occurs, the total commitment amount does not necessarily represent future liquidity requirements. Standby Letter of Credit . A standby letter of credit commits the Company to make payments on behalf of customers if certain specified future events occur. The Company has recourse against the customer for any amount required to be paid to a third party under a standby letter of credit, which is often part of a larger credit agreement under which security is provided. Historically, a large percentage of standby letters of credit expire without being funded. The contractual amount of a standby letter of credit represents the maximum amount of potential future payments the Company could be required to make, and is the Company's maximum credit risk. Commercial Letter of Credit . A commercial letter of credit is issued to facilitate either domestic or foreign trade arrangements for customers. As a general rule, drafts are committed to be drawn when the goods underlying the transaction are in transit. Similar to a standby letter of credit, a commercial letter of credit is often secured by an underlying security agreement including the assets or inventory to which they relate. The following table summarizes the outstanding amounts of credit-related financial instruments with off-balance sheet risk: (In thousands) At September 30, At December 31, 2019 Commitments to extend credit $ 6,287,783 $ 6,162,658 Standby letter of credit 204,981 188,103 Commercial letter of credit 26,270 29,180 Total credit-related financial instruments with off-balance sheet risk $ 6,519,034 $ 6,379,941 These commitments subject the Company to potential exposure in excess of amounts recorded in the financial statements, and therefore, management maintains a reserve for unfunded credit commitments to provide for expected losses in connection with funding the unused portion of legal commitments to lend when those commitments are not unconditionally cancellable by Webster. Loss calculation factors are consistent with the ACL methodology for funded loans using PD and LGD applied to the underlying borrower risk and facility grades, a draw down factor applied to utilization rates, and relevant forecast information. This reserve is reported as a component of accrued expenses and other liabilities on the consolidated balance sheet. The following table provides a summary of activity in the reserve for unfunded credit commitments: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Beginning balance $ 10,739 $ 2,537 $ 2,367 $ 2,506 Adoption of ASU No. 2016-13 (CECL) — — 9,139 — Provision (benefit) charged to non-interest expense 1,146 (68) 379 (37) Ending balance $ 11,885 $ 2,469 $ 11,885 $ 2,469

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2020
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events The Company has evaluated events from the date of the Condensed Consolidated Financial Statements and accompanying Notes thereto, September 30, 2020, through the issuance of this Quarterly Report on Form 10-Q and determined that no significant events were identified requiring recognition or disclosure in this report.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accounting and reporting policies of the Company that materially affect its financial statements conform with U.S. GAAP. The accompanying unaudited Condensed Consolidated Financial Statements of the Company have been prepared in conformity with the instructions for Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all the information and notes required by GAAP for complete financial statements and should be read in conjunction with the Company's Consolidated Financial Statements, and related Notes, for the year ended December 31, 2019, included in our Form 10-K filed with the SEC. There have been no changes to the Company's significant accounting policies from those described within that Form 10-K, except as described within the Recently Adopted Accounting Standards Updates section of this note. Certain prior period amounts have been reclassified to conform to the current year's presentation. These reclassifications had an immaterial effect on the Company's consolidated financial statements.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Loan Modifications Under the CARES Act and Interagency Statement	Loan Modifications Under the CARES Act and Interagency Statement The Coronavirus Aid, Relief, and Economic Security Act (CARES Act) Section 4013, and the Revised Interagency Statement on Loan Modifications and Reporting for Financial Institutions Working with Customers Affected by the Coronavirus. On March 27, 2020, the CARES Act, which provides relief from certain requirements under GAAP, was signed into law. Section 4013 of the CARES Act gives entities temporary relief from the accounting and disclosure requirements for troubled debt restructurings (TDRs) under ASC 310-40 in certain situations. In addition, on April 7, 2020, certain regulatory banking agencies issued an interagency statement that offers practical expedients for evaluating whether loan modifications in response to the COVID-19 pandemic are TDRs. The interagency statement was originally issued on March 22, 2020, but was revised to address the relationship between their original TDR guidance and the guidance in Section 4013 of the CARES Act. To qualify for TDR accounting and disclosure relief under the CARES Act, the applicable loan must not have been more than 30 days past due as of December 31, 2019, and the modification must be executed during the period beginning on March 1, 2020, and ending on the earlier of December 31, 2020, or the date that is 60 days after the termination date of the national emergency declared by the president on March 13, 2020, under the National Emergencies Act related to the outbreak of COVID-19. The CARES Act applies to modifications made as a result of COVID-19 including: forbearance agreements, interest rate modifications, repayment plans, and other arrangements to defer or delay payment of principal or interest. The interagency statement does not require the modification to be completed within a certain time period if it is related to COVID-19 and the loan was not more than 30 days past due as of the date of the Company’s implementation of its modification programs. Moreover, the interagency statement applies to short-term modifications including payment deferrals, fee waivers, extensions of repayment terms, or other insignificant payment delays as a result of COVID-19.
Recently Adopted Accounting Standards Updates	Recently Adopted Accounting Standards Updates Effective January 1, 2020, the following new accounting guidance was adopted by the Company: ASU No. 2020-04, Reference Rate Reform (Topic 848) - Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The Update provides optional expedients and exceptions available to contracts, hedging relationships, and other transactions affected by reference rate reform. In addition to expedients for contract modifications, the Update allows for a one-time transfer or sale of held-to-maturity securities that reference an eligible rate. The Company will consider this one-time securities transfer along with other expedients available under the Update as the Company proceeds with reference rate reform activities. For additional information on reference rate reform refer to the risk factors previously disclosed in Webster's Annual Report on Form 10-K for the year ended December 31, 2019. The Update became effective during the first quarter 2020, and applies to contract modifications and amendments made as of the beginning of the reporting period including the Update issuance date, March 12, 2020, and applies through December 31, 2022. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2019-04, Codification Improvements to Topic 326, Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments. The Update amends guidance on credit losses, hedge accounting, and recognition and measurement of financial instruments. The changes provide clarifications and codification improvements in relation to recently issued accounting updates. The amendments to the guidance on credit losses are considered in the paragraphs below related to our adoption of ASU 2016-13, and has been adopted concurrently with those Updates. The Company adopted the Update during the first quarter 2020 on a prospective basis. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40) - Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. The Update aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The updated guidance also requires an entity to amortize the capitalized implementation costs as an expense over the term of the hosting arrangement and to present in the same income statement line item as the fees associated with the hosting arrangement. The Company adopted the Update during the first quarter 2020 on a prospective basis to all implementation costs incurred after the date of adoption. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2018-13, Fair Value Measurement (Topic 820) - Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement. The Update modifies the disclosure requirements for fair value measurements. The updated guidance no longer requires entities to disclose the amount and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy. However, it requires public companies to disclose changes in unrealized gains and losses for the period included in other comprehensive income (OCI) for recurring Level 3 fair value measurements held at the end of the reporting period and the range and weighted average of significant unobservable inputs used to develop Level 3 measurements. The Company adopted the Update during the first quarter 2020 on a prospective basis. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment. The Update simplifies quantitative goodwill impairment testing by requiring entities to compare the fair value of a reporting unit with its carrying amount and recognize an impairment charge for any amount by which the carrying amount exceeds the fair value of a reporting unit, up to but not exceeding the amount of goodwill allocated to the reporting unit. The Update changes current guidance by eliminating the second step of the goodwill impairment analysis which involves calculating the implied fair value of goodwill determined in the same manner as the amount of goodwill recognized in a business combination upon acquisition. Entities still have the option to first perform a qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. The Company adopted the Update during the first quarter 2020 on a prospective basis. The adoption of this guidance did not have a material effect on the Company's consolidated financial statements. ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments and subsequent ASUs issued to clarify this Topic. The Updates replace the existing incurred loss approach for recognizing credit losses with a new credit loss methodology known as the current expected credit loss (CECL) model. The CECL methodology requires earlier recognition of credit losses using a lifetime credit loss measurement approach for financial assets carried at amortized cost. The Updates also revised the accounting for credit losses on available-for-sale debt securities, which is outside the scope of the CECL methodology. The CECL accounting model applies to all assets measured at amortized cost including loans, net investments in leases, off balance sheet credit exposures, and held-to-maturity debt securities. CECL requires recognition of credit losses at purchase or origination using a lifetime credit loss measurement approach. The allowance for credit losses is based on the composition, characteristics, and credit quality of the loan and securities portfolios as of the reporting date and includes consideration of current economic conditions and reasonable and supportable forecasts at that date. The CECL methodology also requires consideration of a broader range of reasonable and supportable information to determine the allowance for credit losses including economic forecasts. Allowance for credit losses on loans and leases. Under CECL the Company determines its allowance for credit losses on loans and leases collectively, using pools of assets with similar risk characteristics. Loans that no longer match the risk profile of the pool are individually assessed for credit losses. Collective assessments are performed based on two portfolio segments, commercial loans and leases, and consumer loans. Expected losses within the commercial and consumer portfolios are collectively assessed using PD/LGD/EAD framework based on the portfolio or class of financing receivable. The Company’s lifetime credit loss models are based on historical data and incorporate forecasts of macroeconomic variables, qualitative factors, expected prepayments and recoveries. Macroeconomic variables are selected based on the correlation of the variables to credit losses for each class of financing receivable as follows: the commercial model uses unemployment, gross domestic product (GDP), and retail sales; the residential model uses the Case Shiller Home Price Index; home equity loan and line of credit models use interest rate spreads between U.S. Treasuries and corporate bonds and the home equity loan model also uses the Federal Housing Finance Agency (FHFA) home price index; personal loan and credit line models use the Case Shiller and FHFA home price indices. Forecasted economic scenarios are sourced from a third party. Data from the baseline forecast scenario is used in the modeled loss calculation. Qualitative factors are applied to further refine the expected loss calculation for each portfolio considering factors such as credit concentration, credit quality trends, the quality of internal loan reviews, the nature and volume of portfolio growth, staffing levels, underwriting exceptions, and economic considerations not reflected in the base loss model. Other qualitative adjustments may be applied for relevant facts and circumstances expected to impact credit losses. A two year reasonable and supportable forecast period is used for all loan and lease portfolios, subsequently, the expected loss models revert to historical loss rates on a linear basis over a one year period. Historical loss rates are based on approximately 10 years of recently available data and are updated annually. When the risk characteristics of a loan no longer match the characteristics of the collective pool, the loan is removed from the pool and individually assessed for credit losses. Generally, all non-accrual loans, TDRs, potential TDRs, loans with a charge-off, and collateral dependent loans are individually assessed. The individual assessment for credit impairment is generally based on a discounted cash flow approach unless the asset is collateral dependent. A loan is considered collateral dependent when repayment is expected to be provided substantially through the operation or sale of the collateral and the borrower is experiencing financial difficulty. Collateral dependent loans are individually assessed and the expected credit loss is based on the fair value of the collateral. The fair value is reduced for estimated costs to sell if the value of the collateral is expected to be realized through sale. The Company has elected to present accrued interest receivable separately from the amortized cost basis on the balance sheet and is not estimating an allowance for credit loss on accrued interest. This election applies to loans and leases as well as debt securities. The Company's non-accrual policies have not changed as a result of adopting the Updates. Allowance for credit losses on investment securities held-to-maturity. Held-to-maturity debt securities follow the CECL accounting model. Expected losses are calculated on a pooled basis using statistical models which include forecasted scenarios of future economic conditions. The forecasts revert to long-run loss rates implicitly through the economic scenario, generally over three years. If the risk of a held-to-maturity debt security no longer matches the collective assessment pool, it is removed and individually assessed for credit deterioration. A zero credit loss assumption is maintained for U.S. Treasuries and agency-backed securities in both the held-to-maturity and available-for-sale portfolios. The zero loss assumption is re-considered on a quarterly basis to ensure it is still appropriate. Securities are placed on non-accrual status when collection of principal and interest in accordance with contractual terms is doubtful, generally when principal or interest payments become 90 days delinquent unless the security is well secured and in process of collection, or sooner if management concludes circumstances indicate that the borrower may be unable to meet contractual principal or interest payments. Allowance for credit losses on unfunded loan commitments. Accounting for unfunded loan commitments also follows the CECL model, with an allowance recorded on commitments that are not unconditionally cancellable by the Company. 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. The allowance for credit losses on unfunded loan commitments is included in accrued expenses and other liabilities on the consolidated balance sheet and the related credit expense is recorded in other non-interest expense in the consolidated statements of income. Accounting for available-for-sale debt securities. The Updates revised the accounting for available-for-sale debt securities by eliminating the other-than-temporary impairment model, and requiring credit losses be presented as an allowance rather than a direct write-down of available-for-sale debt securities under certain circumstances. Available-for-sale debt securities continue to be recorded at fair value with changes in fair value reflected in OCI. When the fair value of an available-for-sale debt security falls below the amortized cost basis it is evaluated to determine if any of the decline in value is attributable to credit loss. Decreases in fair value attributable to credit loss are recorded directly to earnings with a corresponding allowance for credit losses, limited to the amount that the fair value is less than the amortized cost basis. If the credit quality subsequently improves the allowance is reversed up to a maximum of the previously recorded credit losses. Available-for-sale debt securities follow the same non-accrual policy as held-to-maturity debt securities. 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 recovering the amortized cost basis, the entire fair value adjustment will immediately be recognized in earnings with no corresponding allowance for credit losses. Impact of Adoption . The Company adopted the Updates during the first quarter 2020, using the modified retrospective method. Upon adoption, the Company recorded an increase in its allowance for credit losses as a cumulative effect adjustment. This adjustment, net of tax, reduced the Company's beginning total shareholders' equity at January 1, 2020. Upon adoption, the Company's allowance for credit losses reflected all credit losses expected over the lifetime of the Company's financial assets held at amortized cost. The total increase in allowance and corresponding decrease in equity did not have a material impact to the Company's regulatory capital amounts and ratios. Periods prior to January 1, 2020, are reported in accordance with previously applicable GAAP. The impact of the January 1, 2020, adoption entry is summarized in the table below: December 31, 2019 January 1, 2020 (In thousands) Pre-ASC 326 Adoption Impact of Adoption Reported Under ASC 326 Assets: Allowance for credit losses on investment securities held-to-maturity $ — $ (397) $ (397) Allowance for credit losses on loans and leases (209,096) (57,568) (266,664) Deferred tax assets, net 61,975 15,891 77,866 Liabilities and shareholders' equity: Accrued expenses and other liabilities 153,161 9,139 162,300 Retained earnings 2,061,352 (51,213) 2,010,139 For additional information on accounting for credit losses refer to Note 3: Investment Securities and Note 4: Loans and Leases. Accounting Standards Issued But Not Yet Adopted The following new accounting guidance, applicable to the Company, has been issued by the Financial Accounting Standards Board (FASB) but is pending adoption: ASU No. 2019-12, Income Taxes (Topic 740) - Simplifying the Accounting for Income Taxes. The Update provides simplification to the accounting for income taxes related to a variety of topics and makes minor codification improvements. Changes include a requirement that the effects of an enacted change in tax law be reflected in the computation of the annual effective tax rate in the first interim period that includes the enactment date of the new legislation and clarification on presentation of non-income based taxes. The Update will be effective for the Company on January 1, 2021. The Company does not expect this Update to have a material impact on its consolidated financial statements. ASU No. 2018-14, Compensation-Retirement Benefits - Defined Benefit Plan - General (Subtopic 715-20) - Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans. The Update modifies disclosure requirements for employers that sponsor defined benefit pension and other postretirement plans. The Update will be effective for the Company on January 1, 2021. The Company does not expect this Update to have a material impact on its consolidated financial statements.

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Debt Securities, Held-to-maturity	A summary of the amortized cost, fair value, and allowance for credit losses on investment securities held-to-maturity is presented below: At September 30, 2020 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value Allowance (2) Net Carrying Value Agency CMO $ 116,020 $ 2,743 $ (261) $ 118,502 $ — $ 116,020 Agency MBS 2,595,711 155,221 (106) 2,750,826 — 2,595,711 Agency CMBS 2,033,826 63,401 (599) 2,096,628 — 2,033,826 Municipal bonds and notes 750,847 53,457 — 804,304 306 750,541 CMBS 227,030 9,126 — 236,156 — 227,030 Held-to-maturity securities $ 5,723,434 $ 283,948 $ (966) $ 6,006,416 $ 306 $ 5,723,128 At December 31, 2019 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value Allowance (2) Net Carrying Value Agency CMO $ 167,443 $ 1,123 $ (1,200) $ 167,366 $ — $ 167,443 Agency MBS 2,957,900 60,602 (8,733) 3,009,769 — 2,957,900 Agency CMBS 1,172,491 6,444 (5,615) 1,173,320 — 1,172,491 Municipal bonds and notes 740,431 32,709 (21) 773,119 — 740,431 CMBS 255,653 2,278 (852) 257,079 — 255,653 Held-to-maturity securities $ 5,293,918 $ 103,156 $ (16,421) $ 5,380,653 $ — $ 5,293,918 (1) Amortized cost excludes accrued interest receivable of $18.5 million and $21.8 million at September 30, 2020 and December 31, 2019, respectively, which is included in accrued interest and other assets in the consolidated balance sheet. (2) The Company adopted the new accounting standard for credit losses on January 1, 2020. For periods subsequent to adoption Allowance is calculated under the CECL methodology and the resulting provision includes expected credit losses on held-to-maturity securities. The prior period did not have an allowance under applicable GAAP for that period. The following table summarizes the activity in the allowance for credit losses on investment securities held-to-maturity: Three months ended September 30, 2020 Nine months ended September 30, 2020 (In thousands) Municipal bonds and notes Municipal bonds and notes Balance beginning of period $ 309 $ — Adoption of ASU No. 2016-13 (CECL) — 397 Recovery of credit losses (3) (91) Balance end of period $ 306 $ 306 The following table summarizes credit ratings for amortized cost of held-to-maturity debt securities according to their lowest public credit rating as of September 30, 2020: Investment Grade (In thousands) Aaa Aa1 Aa2 Aa3 A1 A2 A3 Baa2 Not Rated Agency CMOs $ — $ 116,020 $ — $ — $ — $ — $ — $ — $ — Agency MBS — 2,595,711 — — — — — — — Agency CMBS — 2,033,826 — — — — — — — Municipal bonds and notes 209,751 165,261 201,423 117,320 41,697 8,663 2,066 285 4,381 CMBS 227,030 — — — — — — — — Total held-to-maturity $ 436,781 $ 4,910,818 $ 201,423 $ 117,320 $ 41,697 $ 8,663 $ 2,066 $ 285 $ 4,381 The amortized cost and fair value of held-to-maturity debt securities by contractual maturity are set forth below: At September 30, 2020 (In thousands) Amortized Fair Due in one year or less $ 1,085 $ 1,089 Due after one year through five years 5,340 5,611 Due after five through ten years 279,056 295,103 Due after ten years 5,437,953 5,704,613 Total held-to-maturity debt securities $ 5,723,434 $ 6,006,416
Debt Securities, Available-for-sale	A summary of the amortized cost and fair value of available-for-sale securities is presented below: At September 30, 2020 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value (2) Agency CMO $ 166,623 $ 6,908 $ (177) $ 173,354 Agency MBS 1,446,100 81,533 (363) 1,527,270 Agency CMBS 1,024,133 27,621 — 1,051,754 CMBS 464,071 794 (9,840) 455,025 CLO 85,601 1 (1,241) 84,361 Corporate debt 14,551 — (2,098) 12,453 Available-for-sale securities $ 3,201,079 $ 116,857 $ (13,719) $ 3,304,217 At December 31, 2019 (In thousands) Amortized Cost (1) Unrealized Unrealized Fair Value (2) Agency CMO $ 184,500 $ 2,218 $ (917) $ 185,801 Agency MBS 1,580,743 35,456 (4,035) 1,612,164 Agency CMBS 587,974 513 (6,935) 581,552 CMBS 432,085 38 (252) 431,871 CLO 92,628 45 (468) 92,205 Corporate debt 23,485 — (1,245) 22,240 Available-for-sale securities $ 2,901,415 $ 38,270 $ (13,852) $ 2,925,833 (1) Amortized cost excludes accrued interest receivable of $7.4 million and $8.1 million at September 30, 2020 and December 31, 2019, respectively, which is included in accrued interest and other assets in the consolidated balance sheet. (2) Fair value represents net carrying value as there is no allowance for credit losses recorded on investment securities available-for-sale, as the securities are high credit quality, investment grade. The following tables provide information on fair value and unrealized losses for the individual available-for-sale securities with an unrealized loss, for which an allowance for credit losses on investment securities available-for-sale has not been recorded, aggregated by classification and length of time that the individual investment securities have been in a continuous unrealized loss position: At September 30, 2020 Less Than Twelve Months Twelve Months or Longer Total (Dollars in thousands) Fair Unrealized Fair Unrealized # of Fair Unrealized Agency CMO $ 11,358 $ (92) $ 7,935 $ (85) 3 $ 19,293 $ (177) Agency MBS 30,077 (208) 11,591 (155) 30 41,668 (363) Agency CMBS — — — — — — — CMBS 407,322 (9,205) 22,868 (635) 38 430,190 (9,840) CLO 65,711 (589) 18,048 (652) 4 83,759 (1,241) Corporate debt 3,892 (371) 8,561 (1,727) 3 12,453 (2,098) Available-for-sale in unrealized loss position $ 518,360 $ (10,465) $ 69,003 $ (3,254) 78 $ 587,363 $ (13,719) At December 31, 2019 Less Than Twelve Months Twelve Months or Longer Total (Dollars in thousands) Fair Unrealized Fair Unrealized # of Fair Unrealized Agency CMO $ 36,447 $ (352) $ 32,288 $ (565) 9 $ 68,735 $ (917) Agency MBS 41,408 (193) 299,674 (3,842) 79 341,082 (4,035) Agency CMBS 174,406 (1,137) 357,717 (5,798) 34 532,123 (6,935) CMBS 355,260 (232) 7,480 (20) 29 362,740 (252) CLO — — 43,232 (468) 2 43,232 (468) Corporate debt — — 22,240 (1,245) 4 22,240 (1,245) Available-for-sale in unrealized loss position $ 607,521 $ (1,914) $ 762,631 $ (11,938) 157 $ 1,370,152 $ (13,852) The amortized cost and fair value of available-for-sale debt securities by contractual maturity are set forth below: At September 30, 2020 (In thousands) Amortized Fair Due in one year or less $ — $ — Due after one year through five years 601 602 Due after five through ten years 263,579 257,909 Due after ten years 2,936,899 3,045,706 Total available-for-sale debt securities $ 3,201,079 $ 3,304,217

Loans and Leases (Tables)

Loans and Leases (Tables)	6 Months Ended	9 Months Ended
	Jun. 30, 2020	Sep. 30, 2020
Loans and Leases Receivable Disclosure [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable	The following table summarizes loans and leases: (In thousands) At September 30, At December 31, 2019 Commercial non-mortgage $ 7,124,365 $ 5,296,611 Asset-based 889,711 1,046,886 Commercial real estate 6,307,567 5,949,339 Equipment financing 598,473 537,341 Total commercial portfolio 14,920,116 12,830,177 Residential 4,885,821 4,972,685 Home equity 1,867,969 2,014,544 Other consumer 178,117 219,580 Total consumer portfolio 6,931,907 7,206,809 Loans and leases (1) (2) (3) $ 21,852,023 $ 20,036,986 (1) Loan balances include net deferred (fees)/costs and net (premiums)/discounts of $(14.1) million and $17.6 million at September 30, 2020 and December 31, 2019, respectively. (2) At September 30, 2020 the Company had pledged $7.9 billion of eligible loans as collateral to support borrowing capacity at the Federal Home Loan Bank (FHLB) of Boston and the Federal Reserve Bank (FRB) of Boston. (3) Loan balances exclude accrued interest receivable of $56.6 million and $59.0 million at September 30, 2020 and December 31, 2019, respectively, which is included in accrued interest and other assets in the consolidated balance sheet.
Past Due Financing Receivables		The following tables summarize the aging of loans and leases: At September 30, 2020 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Past Due and Non-accrual Current Total Loans Commercial non-mortgage $ 1,027 $ 67 $ — $ 67,849 $ 68,943 $ 7,055,422 $ 7,124,365 Asset-based — — — 3,760 3,760 885,951 889,711 Commercial real estate 330 — — 8,799 9,129 6,298,438 6,307,567 Equipment financing 183 2,550 — 7,182 9,915 588,558 598,473 Residential 4,478 4,787 — 41,554 50,819 4,835,002 4,885,821 Home equity 5,180 1,572 — 32,853 39,605 1,828,364 1,867,969 Other consumer 1,069 556 — 679 2,304 175,813 178,117 Total $ 12,267 $ 9,532 $ — $ 162,676 $ 184,475 $ 21,667,548 $ 21,852,023 At December 31, 2019 (In thousands) 30-59 Days 60-89 Days 90 or More Days Past Due Non-accrual Total Past Due and Non-accrual Current Total Loans Commercial non-mortgage $ 2,094 $ 617 $ — $ 59,369 $ 62,080 $ 5,234,531 $ 5,296,611 Asset-based — — — 139 139 1,046,747 1,046,886 Commercial real estate 1,256 454 — 11,563 13,273 5,936,066 5,949,339 Equipment financing 5,493 292 — 5,433 11,218 526,123 537,341 Residential 7,166 6,441 — 43,193 56,800 4,915,885 4,972,685 Home equity 8,267 5,551 — 30,170 43,988 1,970,556 2,014,544 Other consumer 4,269 807 — 1,192 6,268 213,312 219,580 Total $ 28,545 $ 14,162 $ — $ 151,059 $ 193,766 $ 19,843,220 $ 20,036,986
Financing Receivable, Nonaccrual		The following table provides additional detail related to loans and leases on non-accrual status: At September 30, 2020 At December 31, 2019 (In thousands) Nonaccrual Nonaccrual With No Allowance Nonaccrual Nonaccrual With No Allowance Commercial non-mortgage $ 67,849 $ 12,136 $ 59,369 $ 13,584 Asset-based 3,760 — 139 — Commercial real estate 8,799 2,729 11,563 4,717 Equipment financing 7,182 2,659 5,433 2,159 Total commercial portfolio 87,590 17,524 76,504 20,460 Residential 41,554 30,234 43,193 19,271 Home equity 32,853 25,981 30,170 15,195 Other consumer 679 31 1,192 — Total consumer portfolio 75,086 56,246 74,555 34,466 Total $ 162,676 $ 73,770 $ 151,059 $ 54,926
Activity In Allowance For Losses		The following tables summarize the activity in, as well as the loan and lease balances that were evaluated for, ACL on loans and leases: At or for the three months ended September 30, 2020 At or for the three months ended September 30, 2019 (In thousands) Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total ACL on loans and leases: Balance, beginning of period $ 291,520 $ 67,002 $ 358,522 $ 164,344 $ 47,327 $ 211,671 Adoption of ASU No. 2016-13 (CECL) — — — — — — Provision charged to expense 31,618 (8,865) 22,753 10,603 697 11,300 Charge-offs (13,494) (2,263) (15,757) (11,323) (4,637) (15,960) Recoveries 2,025 2,268 4,293 176 1,965 2,141 Balance, end of period $ 311,669 $ 58,142 $ 369,811 $ 163,800 $ 45,352 $ 209,152 At or for the nine months ended September 30, 2020 At or for the nine months ended September 30, 2019 (In thousands) Commercial Portfolio Consumer Portfolio Total Commercial Portfolio Consumer Portfolio Total ACL on loans and leases: Balance, beginning of period $ 161,669 $ 47,427 $ 209,096 $ 164,073 $ 48,280 $ 212,353 Adoption of ASU No. 2016-13 (CECL) 34,024 23,544 57,568 — — — Provision charged to expense 147,466 (8,625) 138,841 26,513 5,287 31,800 Charge-offs (34,362) (9,630) (43,992) (28,263) (15,113) (43,376) Recoveries 2,872 5,426 8,298 1,477 6,898 8,375 Balance, end of period $ 311,669 $ 58,142 $ 369,811 $ 163,800 $ 45,352 $ 209,152 Individually evaluated for impairment 18,303 4,376 22,679 15,467 4,899 20,366 Collectively evaluated for impairment $ 293,366 $ 53,766 $ 347,132 $ 148,333 $ 40,453 $ 188,786 Loan and lease balances: Individually evaluated for impairment $ 158,324 $ 149,583 $ 307,907 $ 139,129 $ 131,502 $ 270,631 Collectively evaluated for impairment 14,761,792 6,782,324 21,544,116 12,268,839 7,012,176 19,281,015 Loans and leases $ 14,920,116 $ 6,931,907 $ 21,852,023 $ 12,407,968 $ 7,143,678 $ 19,551,646
Impaired Loans		The following tables summarize individually assessed loans and leases: At September 30, 2020 (In thousands) Unpaid Amortized Cost Amortized Cost No Allowance Amortized Cost With Allowance Related Commercial non-mortgage $ 160,667 $ 125,799 $ 28,937 $ 96,862 $ 15,833 Asset-based 4,114 3,760 — 3,760 459 Commercial real estate 24,865 21,583 12,679 8,904 1,613 Equipment financing 7,661 7,182 2,659 4,523 398 Residential 110,542 100,443 63,457 36,986 3,293 Home equity 111,715 48,461 36,477 11,984 1,012 Other consumer 2,321 679 30 649 71 Total $ 421,885 $ 307,907 $ 144,239 $ 163,668 $ 22,679 At December 31, 2019 (In thousands) Unpaid Amortized Cost Amortized Cost No Allowance Amortized Cost With Allowance Related Commercial non-mortgage $ 140,096 $ 102,254 $ 29,739 $ 72,515 $ 7,862 Asset-based 465 139 — 139 5 Commercial real estate 29,292 23,297 14,818 8,479 1,143 Equipment financing 5,591 5,433 2,159 3,274 418 Residential 98,790 90,096 56,231 33,865 3,618 Home equity 38,503 35,191 27,672 7,519 1,203 Other consumer (1) — — — — — Total $ 312,737 $ 256,410 $ 130,619 $ 125,791 $ 14,249 (1) Partially charged-off other consumer loans were included in collectively evaluated for impairment at December 31, 2019. The following table summarizes average amortized cost and interest income recognized for individually assessed loans and leases: Three months ended September 30, Nine months ended September 30, 2020 2019 2020 2019 (In thousands) Average Accrued Cash Basis Interest Income Average Accrued Cash Basis Interest Income Average Accrued Cash Basis Interest Income Average Accrued Cash Basis Interest Income Commercial non-mortgage $ 127,676 $ 954 $ — $ 102,996 $ 751 $ — $ 114,027 $ 2,882 $ — $ 103,772 $ 2,515 $ — Asset-based 1,949 — — 4,673 — — 1,950 — — 4,694 — — Commercial real estate 24,555 192 — 15,051 60 — 22,440 507 — 13,526 194 — Equipment financing 7,488 — — 4,718 — — 6,308 — — 5,901 — — Residential 103,608 741 289 97,917 862 271 95,270 2,352 1,149 99,599 2,682 817 Home equity 49,309 302 297 36,584 247 246 41,826 1,002 1,540 37,490 803 767 Other consumer 948 13 — — — — 340 30 — — — — Total $ 315,533 $ 2,202 $ 586 $ 261,939 $ 1,920 $ 517 $ 282,161 $ 6,773 $ 2,689 $ 264,982 $ 6,194 $ 1,584 The following table summarizes whether, or not, individually assessed loans and leases are collateral dependent: At September 30, 2020 At December 31, 2019 (In thousands) Collateral Dependent Not Considered Collateral Dependent Total Collateral Dependent Not Considered Collateral Dependent Total Commercial non-mortgage $ 11,337 $ 114,462 $ 125,799 $ 10,682 $ 91,572 $ 102,254 Asset-based — 3,760 3,760 — 139 139 Commercial real estate 15,708 5,875 21,583 14,097 9,200 23,297 Equipment financing — 7,182 7,182 — 5,433 5,433 Residential 35,379 65,064 100,443 17,635 72,461 90,096 Home equity 28,857 19,604 48,461 17,136 18,055 35,191 Other consumer — 679 679 — — — Total amortized cost of CDA $ 91,281 $ 216,626 $ 307,907 $ 59,550 $ 196,860 $ 256,410
Financing Receivable Credit Quality Indicators		The following table summarizes commercial, commercial real estate, and equipment financing loans and leases segregated by origination year and risk rating exposure under the Composite Credit Risk Profile grades as of September 30, 2020: (In thousands) 2020 2019 2018 2017 2016 Prior Revolving Loans Amortized Cost Basis Total Commercial non-mortgage Pass $ 2,519,566 $ 1,156,057 $ 1,013,841 $ 553,942 $ 257,230 $ 297,765 $ 912,007 $ 6,710,408 Special mention 817 73,688 20,314 341 8,422 2,302 21,233 127,117 Substandard 1,369 33,658 68,305 75,071 23,138 33,137 51,996 286,674 Doubtful — — — 166 — — — 166 Total commercial non-mortgage 2,521,752 1,263,403 1,102,460 629,520 288,790 333,204 985,236 7,124,365 Asset-based Pass 14,848 21,854 22,595 11,635 11,039 22,667 714,476 819,114 Special mention — 1,667 800 — — 978 63,392 66,837 Substandard — — — — — — 3,760 3,760 Total asset-based 14,848 23,521 23,395 11,635 11,039 23,645 781,628 889,711 Commercial real estate Pass 646,507 1,473,602 1,296,427 605,375 595,915 1,329,377 28,106 5,975,309 Special mention 22 10,382 48,409 27,364 35,796 76,243 — 198,216 Substandard 821 989 23,095 68,828 2,444 37,865 — 134,042 Total commercial real estate 647,350 1,484,973 1,367,931 701,567 634,155 1,443,485 28,106 6,307,567 Equipment financing Pass 203,498 144,384 75,993 31,921 52,328 26,319 — 534,443 Special mention 12,492 13,014 8,471 1,834 1,932 788 — 38,531 Substandard 2,380 5,498 5,563 2,430 4,802 4,826 — 25,499 Total equipment financing 218,370 162,896 90,027 36,185 59,062 31,933 — 598,473 Total commercial portfolio $ 3,402,320 $ 2,934,793 $ 2,583,813 $ 1,378,907 $ 993,046 $ 1,832,267 $ 1,794,970 $ 14,920,116 The following table summarizes residential and consumer loans segregated by origination year and risk rating exposure under FICO score groupings as of September 30, 2020: (In thousands) 2020 2019 2018 2017 2016 Prior Revolving Loans Amortized Cost Basis Total Residential 800+ $ 253,913 $ 314,759 $ 69,592 $ 205,691 $ 316,264 $ 905,892 $ — $ 2,066,111 740-799 458,499 355,548 81,018 164,777 194,784 516,385 — 1,771,011 670-739 161,600 144,798 43,790 77,823 80,481 283,164 — 791,656 580-669 12,316 19,803 7,260 12,010 11,836 102,055 — 165,280 579 and below — 21,363 676 3,771 3,250 62,703 — 91,763 Total residential 886,328 856,271 202,336 464,072 606,615 1,870,199 — 4,885,821 Home equity 800+ 22,727 17,095 27,269 18,031 19,328 66,906 564,318 735,674 740-799 20,580 16,472 23,739 11,659 12,765 49,507 446,759 581,481 670-739 12,122 10,847 10,808 10,506 9,290 45,013 285,776 384,362 580-669 447 2,257 3,346 2,297 1,964 19,707 91,009 121,027 579 and below 100 524 879 1,337 835 7,707 34,043 45,425 Total home equity 55,976 47,195 66,041 43,830 44,182 188,840 1,421,905 1,867,969 Other consumer 800+ 1,345 3,436 1,901 581 115 173 6,851 14,402 740-799 10,419 17,858 9,665 1,491 503 344 6,402 46,682 670-739 21,089 49,734 19,855 4,158 1,616 520 5,676 102,648 580-669 2,440 4,247 1,744 600 253 180 1,623 11,087 579 and below 717 513 250 66 35 225 1,492 3,298 Total other consumer 36,010 75,788 33,415 6,896 2,522 1,442 22,044 178,117 Total consumer portfolio 978,314 979,254 301,792 514,798 653,319 2,060,481 1,443,949 6,931,907 Total commercial portfolio 3,402,320 2,934,793 2,583,813 1,378,907 993,046 1,832,267 1,794,970 14,920,116 Total loans and leases $ 4,380,634 $ 3,914,047 $ 2,885,605 $ 1,893,705 $ 1,646,365 $ 3,892,748 $ 3,238,919 $ 21,852,023
Troubled Debt Restructurings on Financing Receivables		The following table summarizes information for TDRs: (In thousands) At September 30, At December 31, 2019 Accrual status $ 143,544 $ 136,449 Non-accrual status 101,750 100,989 Total TDRs $ 245,294 $ 237,438 Specific reserves for TDRs included in the balance of ACL on loans and leases $ 17,092 $ 12,956 Additional funds committed to borrowers in TDR status 15,345 4,856 The following table provides information on the type of concession for loans and leases modified as TDRs: Three months ended September 30, Nine months ended September 30, 2020 2019 2020 2019 Number of Post- Modification Recorded Investment (1) Number of Post- Modification Recorded Investment (1) Number of Post- Modification Recorded Investment (1) Number of Post- Modification Recorded Investment (1) (Dollars in thousands) Commercial non-mortgage Extended Maturity — $ — 2 $ 29 6 $ 507 8 $ 222 Adjusted Interest Rate — — 1 12 — — 2 112 Maturity/Rate Combined 2 333 3 225 7 607 6 296 Other (2) 1 6 6 30,586 24 40,128 25 64,642 Commercial real estate Extended Maturity — — — — 1 72 — — Maturity/Rate Combined — — — — 1 278 — — Other (2) 3 306 1 2,180 3 306 3 4,816 Residential Extended Maturity 1 134 1 67 3 485 5 1,007 Maturity/Rate Combined 4 425 1 368 9 1,123 14 2,216 Other (2) 2 202 2 243 22 3,877 6 785 Home equity Extended Maturity 1 31 1 134 3 188 5 504 Maturity/Rate Combined 1 15 2 30 2 28 4 140 Other (2) 15 506 8 375 89 6,018 27 1,595 Total TDRs 30 $ 1,958 28 $ 34,249 170 $ 53,617 105 $ 76,335 (1) Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs as a result of the restructurings was not significant. (2) Other includes covenant modifications, forbearance, loans discharged under Chapter 7 bankruptcy, or other concessions. TDRs in commercial, commercial real estate, and equipment financing segregated by risk rating exposure is as follows: (In thousands) At September 30, 2020 At December 31, 2019 Pass $ 12,591 $ 3,952 Special Mention — 63 Substandard 111,613 104,277 Doubtful 166 3,860 Total $ 124,370 $ 112,152

Transfers of Financial Assets (

Transfers of Financial Assets (Tables)	9 Months Ended
	Sep. 30, 2020
Transfers and Servicing [Abstract]
Schedule Of Reserve For Loan Repurchases Table	The following table provides a summary of activity in the reserve for loan repurchases: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Beginning balance $ 655 $ 684 $ 508 $ 674 Provision charged to expense 50 19 99 1,839 (Charge-offs/settlements, net) recoveries, net — (7) 98 (1,817) Ending balance $ 705 $ 696 $ 705 $ 696
Transfer of Financial Assets Accounted for as Sales	The following table provides information for mortgage banking activities: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Residential mortgage loans held for sale: Proceeds from sale $ 172,579 $ 66,236 $ 342,747 $ 129,700 Loans sold with servicing rights retained 164,054 60,493 325,832 117,306 Net gain on sale 6,244 1,652 11,587 2,510 Ancillary fees 1,018 470 2,243 1,051 Fair value option adjustment (175) 11 355 268
Servicing Asset at Amortized Cost	The following table presents the changes in carrying value for mortgage servicing assets: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Beginning balance $ 14,926 $ 18,712 $ 17,484 $ 21,215 Additions 1,301 966 3,269 2,219 Amortization (1,616) (1,801) (4,992) (5,557) Valuation allowance (203) — (1,353) — Ending balance $ 14,408 $ 17,877 $ 14,408 $ 17,877

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Schedule of Components of Leveraged Lease Investments [Table Text Block]	The following table summarizes lessee information related to the Company’s operating ROU assets and lease liability: At September 30, 2020 (In thousands) Operating Leases Consolidated Balance Sheet Line Item Location ROU lease assets $ 146,641 Premises and equipment, net Lease liabilities 165,211 Operating lease liabilities
Lease, Cost [Table Text Block]	The components of operating lease cost and other related information are as follows: At or for the three months ended September 30, At or for the nine months ended September 30, (In thousands) 2020 2019 2020 2019 Lease Cost: Operating lease costs $ 7,381 $ 7,512 $ 22,212 $ 22,384 Variable lease costs 1,297 1,292 4,217 3,613 Sublease income (141) (142) (428) (437) Total operating lease cost $ 8,537 $ 8,662 $ 26,001 $ 25,560 Other Information: Cash paid for amounts included in the measurement of lease liabilities $ 7,823 $ 7,938 $ 23,359 $ 23,349 ROU lease assets obtained in exchange for new operating lease liabilities 856 9,983 9,552 22,917
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	The undiscounted scheduled maturities reconciled to total operating lease liabilities are as follows: (In thousands) At September 30, 2020 Remainder of 2020 $ 5,274 2021 30,604 2022 27,099 2023 24,187 2024 21,307 Thereafter 82,710 Total operating lease liability payments 191,181 Less: Present value adjustment 25,970 Lease liabilities $ 165,211 Weighted-average remaining lease term - operating leases, in years 8.23 Weighted-average discount rate - operating leases 3.22%

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Other intangible assets by reportable segment consisted of the following: At September 30, 2020 At December 31, 2019 (In thousands) Gross Carrying Accumulated Net Carrying Gross Carrying Accumulated Net Carrying HSA Bank - Core deposits $ 26,625 $ 14,875 $ 11,750 $ 22,000 $ 13,073 $ 8,927 HSA Bank - Customer relationships 21,000 9,221 11,779 21,000 8,010 12,990 Total other intangible assets $ 47,625 $ 24,096 $ 23,529 $ 43,000 $ 21,083 $ 21,917
Schedule Of Expected Amortization Expense, Next Four Years	At September 30, 2020, the remaining estimated aggregate future amortization expense for other intangible assets is as follows: (In thousands) Remainder of 2020 $ 1,146 2021 4,513 2022 4,411 2023 4,315 2024 2,084 Thereafter 7,060

Deposits (Tables)

Deposits (Tables)	9 Months Ended
	Sep. 30, 2020
Deposit Liabilities [Abstract]
Deposit Liabilities, Type [Table Text Block]	A summary of deposits by type follows: (In thousands) At September 30, At December 31, Non-interest-bearing: Demand $ 6,136,814 $ 4,446,463 Interest-bearing: Health savings accounts 6,976,280 6,416,135 Checking 3,390,921 2,689,734 Money market 3,069,098 2,312,840 Savings 4,777,000 4,354,809 Time deposits 2,570,440 3,104,765 Total interest-bearing $ 20,783,739 $ 18,878,283 Total deposits $ 26,920,553 $ 23,324,746 Time deposits and interest-bearing checking, included in above balances, obtained through brokers $ 733,691 $ 652,151 Time deposits, included in above balance, that exceed the FDIC limit 533,180 661,334 Deposit overdrafts reclassified as loan balances 1,122 1,721
Time Deposit Maturities [Table Text Block]	The scheduled maturities of time deposits are as follows: (In thousands) At September 30, Remainder of 2020 $ 849,021 2021 1,468,973 2022 141,760 2023 45,774 2024 22,321 Thereafter 42,591 Total time deposits $ 2,570,440

Borrowings (Tables)

Borrowings (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of Repurchase Agreements	The following table summarizes securities sold under agreements to repurchase and other borrowings: At September 30, At December 31, (Dollars in thousands) Amount Rate Amount Rate Securities sold under agreements to repurchase (1) : Original maturity of one year or less $ 278,122 0.19 % $ 240,431 0.19 % Original maturity of greater than one year, non-callable 200,000 0.57 200,000 1.78 Total securities sold under agreements to repurchase 478,122 0.35 440,431 0.91 Fed funds purchased 823,700 0.08 600,000 1.59 Securities sold under agreements to repurchase and other borrowings $ 1,301,822 0.18 $ 1,040,431 1.30
Federal Home Loan Bank, Advances	The following table provides information for FHLB advances: At September 30, 2020 At December 31, 2019 (Dollars in thousands) Amount Weighted- Amount Weighted- Maturing within 1 year $ 175,000 0.88 % $ 1,690,000 1.79 % After 1 but within 2 years 150,024 1.15 200,000 2.53 After 2 but within 3 years 169 1.73 130 — After 3 but within 4 years 50,141 1.59 229 2.95 After 4 but within 5 years 50,000 1.42 50,000 1.59 After 5 years 7,909 2.66 8,117 2.66 FHLB advances $ 433,243 1.15 $ 1,948,476 1.87 Aggregate carrying value of assets pledged as collateral $ 7,561,287 $ 7,318,748 Remaining borrowing capacity 4,506,213 2,937,644
Schedule of Long-term Debt Instruments	The following table summarizes long-term debt: (Dollars in thousands) At September 30, At December 31, 4.375% Senior fixed-rate notes due February 15, 2024 $ 150,000 $ 150,000 4.100% Senior fixed-rate notes due March 25, 2029 (1) 345,502 317,486 Junior subordinated debt Webster Statutory Trust I floating-rate notes due September 17, 2033 (2) 77,320 77,320 Total notes and subordinated debt 572,822 544,806 Discount on senior fixed-rate notes (1,247) (1,412) Debt issuance cost on senior fixed-rate notes (2,729) (3,030) Long-term debt $ 568,846 $ 540,364 (1) The Company has de-designated its fair value hedging relationship on these notes. The $45.5 million basis adjustment included in the carrying value at September 30, 2020 is being amortized over the remaining life of the notes. (2) The interest rate on Webster Statutory Trust I floating-rate notes, which varies quarterly based on 3-month London Interbank Offered Rate plus 2.95%, was 3.20% at September 30, 2020 and 4.85% at December 31, 2019.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income, Net of Tax (Tables)	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Schedule of Changes in Accumulated Other Comprehensive Loss by Component	The following tables summarize the changes in accumulated other comprehensive income (loss), net of tax, by component: Three months ended September 30, 2020 Nine months ended September 30, 2020 (In thousands) Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Beginning balance $ 63,476 $ 20,649 $ (42,680) $ 41,445 $ 17,251 $ (9,184) $ (44,139) $ (36,072) OCI before reclassifications 11,766 (3,310) — 8,456 57,997 23,655 — 81,652 Amounts reclassified from AOCI — 1,398 738 2,136 (6) 4,266 2,197 6,457 Net current-period OCI 11,766 (1,912) 738 10,592 57,991 27,921 2,197 88,109 Ending balance $ 75,242 $ 18,737 $ (41,942) $ 52,037 $ 75,242 $ 18,737 $ (41,942) $ 52,037 Three months ended September 30, 2019 Nine months ended September 30, 2019 (In thousands) Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Securities Available For Sale Derivative Instruments Defined Benefit Pension and Other Postretirement Benefit Plans Total Beginning balance $ (9,406) $ (8,931) $ (47,853) $ (66,190) $ (71,374) $ (9,313) $ (49,965) $ (130,652) OCI/OCL before reclassifications 24,304 2,216 — 26,520 86,272 507 — 86,779 Amounts reclassified from AOCL — 1,387 1,049 2,436 — 3,478 3,161 6,639 Net current-period OCI 24,304 3,603 1,049 28,956 86,272 3,985 3,161 93,418 Ending balance $ 14,898 $ (5,328) $ (46,804) $ (37,234) $ 14,898 $ (5,328) $ (46,804) $ (37,234)
Schedule of Accumulated Other Comprehensive Loss	The following table provides information for the items reclassified from AOCI/AOCL: (In thousands) Three months ended September 30, Nine months ended September 30, Associated Line Item in the Condensed Consolidated Statements of Income AOCI/AOCL Components 2020 2019 2020 2019 Securities available-for-sale: Unrealized gains on investment securities $ — $ — $ 8 $ — Gain on sale of investment securities, net Tax expense — — (2) — Income tax expense Net of tax $ — $ — $ 6 $ — Derivative instruments: Premium amortization and hedge terminations $ (967) $ (1,375) $ (3,228) $ (4,174) Interest expense Premium amortization (926) (515) (2,548) (527) Interest income Tax benefit 495 503 1,510 1,223 Income tax expense Net of tax $ (1,398) $ (1,387) $ (4,266) $ (3,478) Defined benefit pension and other postretirement benefit plans: Amortization of net loss $ (1,002) $ (1,421) $ (2,982) $ (4,280) Other non-interest expense Tax benefit 264 372 785 1,119 Income tax expense Net of tax $ (738) $ (1,049) $ (2,197) $ (3,161)

Regulatory Matters (Tables)

Regulatory Matters (Tables)	9 Months Ended
	Sep. 30, 2020
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Information On The Capital Ratios	The following table provides information on the capital ratios for Webster Financial Corporation and Webster Bank: At September 30, 2020 Actual (1) Minimum Requirement Well Capitalized (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 risk-based capital $ 2,519,589 11.23 % $ 1,009,651 4.5 % $ 1,458,385 6.5 % Total risk-based capital 3,022,511 13.47 1,794,935 8.0 2,243,669 10.0 Tier 1 risk-based capital 2,664,626 11.88 1,346,201 6.0 1,794,935 8.0 Tier 1 leverage capital 2,664,626 8.24 1,293,186 4.0 1,616,482 5.0 Webster Bank CET1 risk-based capital $ 2,744,235 12.24 % $ 1,009,277 4.5 % $ 1,457,845 6.5 % Total risk-based capital 3,024,694 13.49 1,794,270 8.0 2,242,838 10.0 Tier 1 risk-based capital 2,744,235 12.24 1,345,703 6.0 1,794,270 8.0 Tier 1 leverage capital 2,744,235 8.49 1,292,763 4.0 1,615,954 5.0 At December 31, 2019 Actual Minimum Requirement Well Capitalized (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Webster Financial Corporation CET1 risk-based capital $ 2,516,361 11.56 % $ 979,739 4.5 % $ 1,415,179 6.5 % Total risk-based capital 2,950,181 13.55 1,741,758 8.0 2,177,198 10.0 Tier 1 risk-based capital 2,661,398 12.22 1,306,319 6.0 1,741,758 8.0 Tier 1 leverage capital 2,661,398 8.96 1,188,507 4.0 1,485,634 5.0 Webster Bank CET1 risk-based capital $ 2,527,645 11.61 % $ 979,497 4.5 % $ 1,414,829 6.5 % Total risk-based capital 2,739,108 12.58 1,741,328 8.0 2,176,660 10.0 Tier 1 risk-based capital 2,527,645 11.61 1,305,996 6.0 1,741,328 8.0 Tier 1 leverage capital 2,527,645 8.51 1,187,953 4.0 1,484,941 5.0

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Earnings Per Share Basic And Diluted	Reconciliation of the calculation of basic and diluted earnings per common share follows: Three months ended September 30, Nine months ended September 30, (In thousands, except per share data) 2020 2019 2020 2019 Earnings for basic and diluted earnings per common share: Net income $ 69,281 $ 93,865 $ 160,577 $ 292,250 Less: Preferred stock dividends 1,968 1,968 5,906 5,906 Net income available to common shareholders 67,313 91,897 154,671 286,344 Less: Earnings applicable to participating securities (1) 423 455 913 1,425 Earnings applicable to common shareholders $ 66,890 $ 91,442 $ 153,758 $ 284,919 Shares: Weighted-average common shares outstanding - basic 89,630 91,559 90,076 91,554 Effect of dilutive securities 108 315 159 329 Weighted-average common shares outstanding - diluted 89,738 91,874 90,235 91,883 Earnings per common share (1) : Basic $ 0.75 $ 1.00 $ 1.71 $ 3.11 Diluted 0.75 1.00 1.70 3.10

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2020
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 of derivative positions: At September 30, 2020 At December 31, 2019 Asset Derivatives Liability Derivatives Asset Derivatives Liability Derivatives (In thousands) Notional Fair Notional Fair Notional Fair Notional Fair Designated as hedging instruments: Interest rate derivatives (1) $ 1,150,000 $ 44,114 $ 25,000 $ 145 $ 1,225,000 $ 11,855 $ 300,000 $ 3,153 Not designated as hedging instruments: Interest rate derivatives (1) 4,642,373 341,275 4,505,792 17,212 4,869,139 133,455 4,090,522 9,732 Mortgage banking derivatives (2) 105,605 2,717 — — 27,873 329 57,000 110 Other (3) 111,089 333 351,288 890 76,544 398 275,279 818 Total not designated as hedging instruments 4,859,067 344,325 4,857,080 18,102 4,973,556 134,182 4,422,801 10,660 Gross derivative instruments, before netting $ 6,009,067 388,439 $ 4,882,080 18,247 $ 6,198,556 146,037 $ 4,722,801 13,813 Less: Master netting agreements 12,390 12,390 4,779 4,779 Cash collateral 32,159 5,085 8,100 1,871 Total derivative instruments, after netting $ 343,890 $ 772 $ 133,158 $ 7,163 (1) Balances related to Chicago Mercantile Exchange (CME) are presented as a single unit of account. In accordance with its rule book, CME legally characterizes variation margin payments as settlement of derivatives rather than collateral against derivative positions. Notional amounts of interest rate swaps cleared through CME include $60.1 million and $1.1 billion for asset derivatives and $3.4 billion and $2.6 billion for liability derivatives at September 30, 2020 and December 31, 2019, respectively. The related fair values approximate zero. (2) Notional amounts related to residential loans exclude approved floating rate commitments of $10.8 million at September 30, 2020. (3) Other derivatives include foreign currency forward contracts related to lending arrangements and customer hedging activity, a Visa equity swap transaction, and risk participation agreements (RPAs). Notional amounts of RPAs include $95.4 million and $65.7 million for asset derivatives and $317.8 million and $223.4 million for liability derivatives at September 30, 2020 and December 31, 2019, respectively, that have insignificant related fair values.
Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The following table presents fair value positions transitioned from gross to net upon applying counterparty netting agreements: At September 30, 2020 (In thousands) Gross Offset Amount Net Amount on Balance Sheet Amounts Not Offset Net Amounts Asset derivatives $ 44,549 $ 44,549 $ — $ 196 $ 196 Liability derivatives 17,568 17,475 93 1,041 1,134 At December 31, 2019 (In thousands) Gross Offset Amount Net Amount on Balance Sheet Amounts Not Offset Net Amounts Asset derivatives $ 13,012 $ 12,879 $ 133 $ 299 $ 432 Liability derivatives 6,710 6,650 60 329 389
Schedule of Net Investment Hedges, Statements of Financial Performance and Financial Position, Location [Table Text Block]	The following tables present the income statement effect of derivatives designated as hedges and additional information related to a fair value hedging adjustment: Recognized In Three months ended September 30, Nine months ended September 30, (In thousands) Net Interest Income 2020 2019 2020 2019 Fair value hedges: (1) Recognized on derivatives Long-term debt $ — $ 10,624 $ 30,693 $ 26,436 Recognized on hedged items Long-term debt — (10,624) (30,693) (26,436) Net recognized on fair value hedges $ — $ — $ — $ — Cash flow hedges: Interest rate derivatives Long-term debt $ 1,152 $ 1,095 $ 3,501 $ 3,028 Interest rate derivatives Interest and fees on loans and leases (2,657) 515 (3,754) 527 Net recognized on cash flow hedges $ (1,505) $ 1,610 $ (253) $ 3,555 Consolidated Balance Sheet Line Item in Which Hedged Item is Located Carrying Amount of Hedged Item Cumulative Amount of Fair Value Hedging Adjustment Included in Carrying Amount (1) (In thousands) At September 30, At December 31, At September 30, At December 31, Long-term debt $ 345,502 $ 317,486 $ 45,502 $ 17,486 (1) The Company has de-designated its fair value hedging relationship on the long-term debt, which resulted in a $48.2 million basis adjustment that is being amortized over the remaining life of the notes through interest expense.
Other Derivatives Not Designated For Hedge Accounting	The following table presents the effect on the income statement for derivatives not designated as hedging instruments: Recognized In Three months ended September 30, Nine months ended September 30, (In thousands) Non-interest Income 2020 2019 2020 2019 Interest rate derivatives Other income $ 3,824 $ 784 $ 7,227 $ 5,906 Mortgage banking derivatives Mortgage banking activities 872 347 2,498 96 Other Other income (1,229) 1,679 (332) 1,603 Total not designated as hedging instruments $ 3,467 $ 2,810 $ 9,393 $ 7,605

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Option, Disclosures	At September 30, 2020 At December 31, 2019 (In thousands) Fair Value Unpaid Principal Balance Difference Fair Value Unpaid Principal Balance Difference Originated loans held for sale $ 29,018 $ 28,433 $ 585 $ 35,750 $ 35,186 $ 564
Fair Value Of Assets And Liabilities Measured On Recurring Basis	Summaries of the fair values of assets and liabilities measured at fair value on a recurring basis are as follows: At September 30, 2020 (In thousands) Level 1 Level 2 Level 3 Total Financial assets held at fair value: Agency CMO $ — $ 173,354 $ — $ 173,354 Agency MBS — 1,527,270 — 1,527,270 Agency CMBS — 1,051,754 — 1,051,754 CMBS — 455,025 — 455,025 CLO — 84,361 — 84,361 Corporate debt — 12,453 — 12,453 Total available-for-sale investment securities — 3,304,217 — 3,304,217 Gross derivative instruments, before netting (1) 209 388,230 — 388,439 Originated loans held for sale — 29,018 — 29,018 Investments held in Rabbi Trust 4,657 — — 4,657 Alternative investments (2) — — — 8,238 Total financial assets held at fair value $ 4,866 $ 3,721,465 $ — $ 3,734,569 Financial liabilities held at fair value: Gross derivative instruments, before netting (1) $ 229 $ 18,018 $ — $ 18,247 At December 31, 2019 (In thousands) Level 1 Level 2 Level 3 Total Financial assets held at fair value: Agency CMO $ — $ 185,801 $ — $ 185,801 Agency MBS — 1,612,164 — 1,612,164 Agency CMBS — 581,552 — 581,552 CMBS — 431,871 — 431,871 CLO — 92,205 — 92,205 Corporate debt — 22,240 — 22,240 Total available-for-sale investment securities — 2,925,833 — 2,925,833 Gross derivative instruments, before netting (1) 328 145,709 — 146,037 Originated loans held for sale — 35,750 — 35,750 Investments held in Rabbi Trust 4,780 — — 4,780 Alternative investments (2) — — — 4,331 Total financial assets held at fair value $ 5,108 $ 3,107,292 $ — $ 3,116,731 Financial liabilities held at fair value: Gross derivative instruments, before netting (1) $ 611 $ 13,202 $ — $ 13,813 (1) For information relating to the impact of netting derivative assets and derivative liabilities as well as the impact from offsetting cash collateral paid to the same derivative counterparties see Note 13: Derivative Financial Instruments. (2) 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 estimated fair value of selected financial instruments and servicing assets are as follows: At September 30, 2020 At December 31, 2019 (In thousands) Carrying Fair Carrying Fair Assets: Level 2 Held-to-maturity investment securities $ 5,723,128 $ 6,006,416 $ 5,293,918 $ 5,380,653 Level 3 Loans and leases, net 21,482,212 21,695,557 19,827,890 19,961,632 Mortgage servicing assets 14,408 15,559 17,484 33,250 Liabilities: Level 2 Deposit liabilities $ 24,350,113 $ 24,350,113 $ 20,219,981 $ 20,219,981 Time deposits 2,570,440 2,580,279 3,104,765 3,102,316 Securities sold under agreements to repurchase and other borrowings 1,301,822 1,305,029 1,040,431 1,041,042 FHLB advances 433,243 442,724 1,948,476 1,950,035 Long-term debt (1) 568,846 525,170 540,364 555,775 (1) Adjustments to the carrying amount of long-term debt for basis adjustment and unamortized discount and debt issuance cost on senior fixed-rate notes are not included for determination of fair value Refer to Note 9: Borrowings for additional information.

Retirement Benefit Plans (Table

Retirement Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2020
Retirement Benefits [Abstract]
Summary of Net Periodic Benefit Cost	The following table summarizes the components of net periodic benefit cost: Three months ended September 30, 2020 2019 (In thousands) Pension Plan SERP Other Benefits Pension Plan SERP Other Benefits Interest cost on benefit obligations $ 1,531 $ 12 $ 9 $ 2,001 $ 16 $ 22 Expected return on plan assets (3,380) — — (2,815) — — Recognized net loss 1,036 5 (38) 1,420 4 (2) Net periodic benefit cost $ (813) $ 17 $ (29) $ 606 $ 20 $ 20 Nine months ended September 30, 2020 2019 (In thousands) Pension Plan SERP Other Benefits Pension Plan SERP Other Benefits Interest cost on benefit obligations $ 4,881 $ 35 $ 34 $ 5,956 $ 48 $ 64 Expected return on plan assets (10,140) — — (8,445) — — Recognized net loss 3,021 17 (55) 4,280 11 (10) Net periodic benefit cost $ (2,238) $ 52 $ (21) $ 1,791 $ 59 $ 54

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Operating Results And Total Assets Reportable Segments	The following table presents total assets for Webster's reportable segments and the Corporate and Reconciling category: (In thousands) Commercial HSA Community Corporate and Consolidated At September 30, 2020 $ 12,666,764 $ 83,104 $ 10,039,505 $ 10,205,070 $ 32,994,443 At December 31, 2019 11,541,803 80,176 9,348,727 9,418,638 30,389,344 The following tables present the operating results, including all appropriate allocations, for Webster’s reportable segments and the Corporate and Reconciling category: Three months ended September 30, 2020 (In thousands) Commercial HSA Community Banking Corporate and Consolidated Net interest income $ 107,417 $ 39,861 $ 108,218 $ (36,240) $ 219,256 Non-interest income 13,099 27,235 28,970 5,756 75,060 Non-interest expense 47,610 34,789 98,991 2,606 183,996 Pre-tax, pre-provision net revenue 72,906 32,307 38,197 (33,090) 110,320 Provision for credit losses 30,793 — (8,040) (3) 22,750 Income before income tax expense 42,113 32,307 46,237 (33,087) 87,570 Income tax expense 10,314 8,626 9,155 (9,806) 18,289 Net income $ 31,799 $ 23,681 $ 37,082 $ (23,281) $ 69,281 Three months ended September 30, 2019 (In thousands) Commercial HSA Community Banking Corporate and Consolidated Net interest income $ 104,549 $ 43,581 $ 104,613 $ (12,204) $ 240,539 Non-interest income 13,987 23,526 28,115 4,303 69,931 Non-interest expense 45,261 32,918 99,835 1,880 179,894 Pre-tax, pre-provision net revenue 73,275 34,189 32,893 (9,781) 130,576 Provision for credit losses 9,312 — 1,988 — 11,300 Income before income tax expense 63,963 34,189 30,905 (9,781) 119,276 Income tax expense 15,863 9,060 6,552 (6,064) 25,411 Net income $ 48,100 $ 25,129 $ 24,353 $ (3,717) $ 93,865 Nine months ended September 30, 2020 (In thousands) Commercial HSA Community Banking Corporate and Consolidated Net interest income $ 311,595 $ 121,868 $ 312,558 $ (71,557) $ 674,464 Non-interest income 41,063 76,721 79,995 10,735 208,514 Non-interest expense 138,848 105,887 291,644 3,037 $ 539,416 Pre-tax, pre-provision net revenue 213,810 $ 92,702 100,909 (63,859) 343,562 Provision for credit losses 131,876 — 6,965 (91) 138,750 Income before income tax expense 81,934 92,702 93,944 (63,768) 204,812 Income tax expense 20,066 24,751 18,601 (19,183) 44,235 Net income $ 61,868 $ 67,951 $ 75,343 $ (44,585) $ 160,577 Nine months ended September 30, 2019 (In thousands) Commercial HSA Community Corporate and Consolidated Net interest income $ 303,107 $ 130,692 $ 318,741 $ (28,663) $ 723,877 Non-interest income 42,643 74,082 81,172 16,499 214,396 Non-interest expense 136,075 100,693 291,076 8,376 536,220 Pre-tax, pre-provision net revenue 209,675 104,081 108,837 (20,540) 402,053 Provision for credit losses 23,294 — 8,506 — 31,800 Income before income tax expense 186,381 104,081 100,331 (20,540) 370,253 Income tax expense 46,224 27,582 21,269 (17,072) 78,003 Net income $ 140,157 $ 76,499 $ 79,062 $ (3,468) $ 292,250

Revenue from Contracts with C_2

Revenue from Contracts with Customers Disaggregation of Revenue (Tables)	9 Months Ended
	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue [Table Text Block]	The following tables present revenues within the scope of ASC 606, Revenue from Contracts with Customers and the net amount of other sources of non-interest income that is within the scope of other GAAP topics: Three months ended September 30, 2020 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 2,883 $ 23,667 $ 12,704 $ 24 $ 39,278 Wealth and investment services 2,669 — 5,565 21 8,255 Other — 3,568 526 — 4,094 Revenue from contracts with customers 5,552 27,235 18,795 45 51,627 Other sources of non-interest income 7,547 — 10,175 5,711 23,433 Total non-interest income $ 13,099 $ 27,235 $ 28,970 $ 5,756 $ 75,060 Three months ended September 30, 2019 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 2,987 $ 22,264 $ 16,047 $ 112 $ 41,410 Wealth and investment services 2,650 — 5,855 (9) 8,496 Other — 1,262 650 — 1,912 Revenue from contracts with customers 5,637 23,526 22,552 103 51,818 Other sources of non-interest income 8,350 — 5,563 4,200 18,113 Total non-interest income $ 13,987 $ 23,526 $ 28,115 $ 4,303 $ 69,931 Nine months ended September 30, 2020 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 8,645 $ 70,250 $ 38,784 $ 8 $ 117,687 Wealth and investment services 7,784 — 16,336 (24) 24,096 Other — 6,471 1,583 — 8,054 Revenue from contracts with customers 16,429 76,721 56,703 (16) 149,837 Other sources of non-interest income 24,634 — 23,292 10,751 58,677 Total non-interest income $ 41,063 $ 76,721 $ 79,995 $ 10,735 $ 208,514 Nine months ended September 30, 2019 (In thousands) Commercial HSA Community Corporate and Consolidated Non-interest Income: Deposit service fees $ 9,108 $ 70,496 $ 47,701 $ 247 $ 127,552 Wealth and investment services 7,676 — 16,806 (26) 24,456 Other — 3,586 1,855 — 5,441 Revenue from contracts with customers 16,784 74,082 66,362 221 157,449 Other sources of non-interest income 25,859 — 14,810 16,278 56,947 Total non-interest income $ 42,643 $ 74,082 $ 81,172 $ 16,499 $ 214,396

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Outstanding Financial Instruments Contract Amounts Represent Credit Risk	The following table summarizes the outstanding amounts of credit-related financial instruments with off-balance sheet risk: (In thousands) At September 30, At December 31, 2019 Commitments to extend credit $ 6,287,783 $ 6,162,658 Standby letter of credit 204,981 188,103 Commercial letter of credit 26,270 29,180 Total credit-related financial instruments with off-balance sheet risk $ 6,519,034 $ 6,379,941
Reserve For Unfunded Credit Commitments	The following table provides a summary of activity in the reserve for loan repurchases: Three months ended September 30, Nine months ended September 30, (In thousands) 2020 2019 2020 2019 Beginning balance $ 655 $ 684 $ 508 $ 674 Provision charged to expense 50 19 99 1,839 (Charge-offs/settlements, net) recoveries, net — (7) 98 (1,817) Ending balance $ 705 $ 696 $ 705 $ 696

Summary of Significant Accoun_3

Summary of Significant Accounting Policies New Accounting Pronouncements or Change in Accounting Principle (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)Segment	Jun. 30, 2020USD ($)	Jan. 01, 2020USD ($)	Dec. 31, 2019USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of portfolio segments | Segment	2
Allowance for credit losses on loans and leases, forecast perod	2 years
Allowance for credit losses on loans and leases, historical loss rate period	1 year
Allowance for credit losses on investment securities held-to-maturity, long-run loss rate period	3 years
Allowance for credit losses on investment securities held-to-maturity	$ (306)	$ (309)		$ 0
Allowance for credit losses on loans and leases				(209,096)
Deferred Tax Assets, Tax Deferred Expense				61,975
Accrued expenses and other liabilities	385,078			153,161
Retained earnings	2,055,620			$ 2,061,352
Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses on investment securities held-to-maturity	(397)		$ (397)
Allowance for credit losses on loans and leases	(57,568)		(266,664)
Deferred Tax Assets, Tax Deferred Expense	15,891		77,866
Accrued expenses and other liabilities	9,139		162,300
Retained earnings	$ (51,213)		$ 2,010,139

Variable Interest Entities (Var

Variable Interest Entities (Variable Interest Entity, Consolidated, Carrying Amount, Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Assets	$ 32,994,443	$ 30,389,344
Liabilities	29,774,753	27,181,574
Other Assets [Member] | Tax Credit - Finance Investments | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Assets	38,500	42,500
Accounts Payable and Accrued Liabilities [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Liabilities		15,100
Accounts Payable and Accrued Liabilities [Member] | Tax Credit - Finance Investments | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Liabilities	14,200
Other Investments [Member] | Other Non-Marketable Investments | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Assets	28,400	21,800
Unfunded Loan Commitment [Member] | Other Non-Marketable Investments | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 70,500	$ 64,200

Investments, Debt and Equity Se

Investments, Debt and Equity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Investment securities held-to-maturity, net	$ 5,723,434		$ 5,293,918
Unrealized Gains	283,948		103,156
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	966		16,421
Debt Securities, Held-to-maturity, Fair Value	6,006,416		5,380,653
Allowance for credit losses on investment securities held-to-maturity	306	$ 309	0
Net Carrying Value	5,723,128		5,293,918
Interest receivable	56,600		59,000
Held-to-maturity Securities [Member]
Schedule of Investments [Line Items]
Interest receivable	18,500		21,800
Agency CMO [Member]
Schedule of Investments [Line Items]
Investment securities held-to-maturity, net	116,020		167,443
Unrealized Gains	2,743		1,123
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	261		1,200
Debt Securities, Held-to-maturity, Fair Value	118,502		167,366
Allowance for credit losses on investment securities held-to-maturity	0		0
Net Carrying Value	116,020		167,443
Agency MBS [Member]
Schedule of Investments [Line Items]
Investment securities held-to-maturity, net	2,595,711		2,957,900
Unrealized Gains	155,221		60,602
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	106		8,733
Debt Securities, Held-to-maturity, Fair Value	2,750,826		3,009,769
Allowance for credit losses on investment securities held-to-maturity	0		0
Net Carrying Value	2,595,711		2,957,900
Agency Commercial Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Investment securities held-to-maturity, net	2,033,826		1,172,491
Unrealized Gains	63,401		6,444
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	599		5,615
Debt Securities, Held-to-maturity, Fair Value	2,096,628		1,173,320
Allowance for credit losses on investment securities held-to-maturity	0		0
Net Carrying Value	2,033,826		1,172,491
Municipal Bonds [Member]
Schedule of Investments [Line Items]
Investment securities held-to-maturity, net	750,847		740,431
Unrealized Gains	53,457		32,709
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	0		21
Debt Securities, Held-to-maturity, Fair Value	804,304		773,119
Allowance for credit losses on investment securities held-to-maturity	306		0
Net Carrying Value	750,541		740,431
Non-agency CMBS [Member]
Schedule of Investments [Line Items]
Investment securities held-to-maturity, net	227,030		255,653
Unrealized Gains	9,126		2,278
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	0		852
Debt Securities, Held-to-maturity, Fair Value	236,156		257,079
Allowance for credit losses on investment securities held-to-maturity	0		0
Net Carrying Value	$ 227,030		$ 255,653

Investments, Debt and Equity _2

Investments, Debt and Equity Securities Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Beginning Balance	$ 309	$ 0
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Recovery	(3)	(91)
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Ending Balance	306	306
Cumulative Effect, Period of Adoption, Adjustment
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Roll Forward]
Debt Securities, Held-to-maturity, Allowance for Credit Loss, Beginning Balance	$ 0	$ 397

Investment Securities (Summary

Investment Securities (Summary Of Debt Securities Held-to Maturity) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Held-to-maturity, Amortized Cost - Due in one year or less	$ 1,085
Held-to-maturity, Amortized Cost - Due after one year through five years	5,340
Held-to-maturity, Amortized Cost - Due after five through ten years	279,056
Held-to-maturity, Amortized Cost - Due after ten years	5,437,953
Amortized Cost(1)	5,723,434	$ 5,293,918
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Held to maturity, Fair Value - Due in one year or less	1,089
Held-to-maturity, Fair Value - Due after one year through five years	5,611
Held to maturity, Fair Value - Due after five through ten years	295,103
Held to maturity, Fair Value - Due after ten years	5,704,613
Fair Value(2)	6,006,416	5,380,653
Moody's, Aaa Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	436,781
Moody's, Aa1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	4,910,818
Moody's, Aa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	201,423
Moody's, Aa3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	117,320
Moody's, A1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	41,697
Moody's, A2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	8,663
Moody's, A3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	2,066
Moody's, Baa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	285
Moody's, Not Rated
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	4,381
Agency CMO [Member]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	116,020	167,443
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Fair Value(2)	118,502	167,366
Agency CMO [Member] | Moody's, Aaa Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, Aa1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	116,020
Agency CMO [Member] | Moody's, Aa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, Aa3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, A1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, A2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, A3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, Baa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMO [Member] | Moody's, Not Rated
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	2,595,711	2,957,900
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Fair Value(2)	2,750,826	3,009,769
Agency MBS [Member] | Moody's, Aaa Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, Aa1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	2,595,711
Agency MBS [Member] | Moody's, Aa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, Aa3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, A1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, A2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, A3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, Baa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency MBS [Member] | Moody's, Not Rated
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	2,033,826	1,172,491
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Fair Value(2)	2,096,628	1,173,320
Agency CMBS [Member] | Moody's, Aaa Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, Aa1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	2,033,826
Agency CMBS [Member] | Moody's, Aa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, Aa3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, A1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, A2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, A3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, Baa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Agency CMBS [Member] | Moody's, Not Rated
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Municipal bonds and notes [Member]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	750,847	740,431
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Fair Value(2)	804,304	773,119
Municipal bonds and notes [Member] | Moody's, Aaa Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	209,751
Municipal bonds and notes [Member] | Moody's, Aa1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	165,261
Municipal bonds and notes [Member] | Moody's, Aa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	201,423
Municipal bonds and notes [Member] | Moody's, Aa3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	117,320
Municipal bonds and notes [Member] | Moody's, A1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	41,697
Municipal bonds and notes [Member] | Moody's, A2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	8,663
Municipal bonds and notes [Member] | Moody's, A3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	2,066
Municipal bonds and notes [Member] | Moody's, Baa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	285
Municipal bonds and notes [Member] | Moody's, Not Rated
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	4,381
Non-agency CMBS [Member]
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	227,030	255,653
Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract]
Fair Value(2)	236,156	$ 257,079
Non-agency CMBS [Member] | Moody's, Aaa Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	227,030
Non-agency CMBS [Member] | Moody's, Aa1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, Aa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, Aa3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, A1 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, A2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, A3 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, Baa2 Rating
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	0
Non-agency CMBS [Member] | Moody's, Not Rated
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract]
Amortized Cost(1)	$ 0

Investment Securities (Summar_2

Investment Securities (Summary Of Debt Securities Available-for-Sale) (Detail) $ in Thousands	Sep. 30, 2020USD ($)numberOfHoldings	Dec. 31, 2019USD ($)numberOfHoldings
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	$ 3,201,079	$ 2,901,415
Unrealized Gains	116,857	38,270
Unrealized Losses	(13,719)	(13,852)
Investment securities available-for-sale, at fair value	3,304,217	2,925,833
Interest receivable	56,600	59,000
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	518,360	607,521
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(10,465)	(1,914)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	69,003	762,631
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (3,254)	$ (11,938)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings	78	157
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 587,363	$ 1,370,152
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(13,719)	(13,852)
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	0
Available-for-sale, Amortized Cost - Due after one year through five years	601
Available-for-sale, Amortized Cost - Due after five through ten years	263,579
Available-for-sale, Amortized Cost - Due after ten years	2,936,899
Available-for-sale, Amortized Cost - Total debt securities	3,201,079	2,901,415
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Available-for-sale, Fair Value - Due in one year or less	0
Available-for-sale, Fair Value - Due after one year through five years	602
Available-for-sale, Fair Value - Due after five through ten years	257,909
Available-for-sale, Fair Value - Due after ten years	3,045,706
Debt Securities, Available-for-sale	3,304,217	2,925,833
Available-for-sale Securities [Member]
Debt Securities, Available-for-sale [Abstract]
Interest receivable	7,400	8,100
Agency CMO [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	166,623	184,500
Unrealized Gains	6,908	2,218
Unrealized Losses	(177)	(917)
Investment securities available-for-sale, at fair value	173,354	185,801
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	11,358	36,447
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(92)	(352)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	7,935	32,288
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (85)	$ (565)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings	3	9
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 19,293	$ 68,735
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(177)	(917)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Available-for-sale, Amortized Cost - Total debt securities	166,623	184,500
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale	173,354	185,801
Agency MBS [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	1,446,100	1,580,743
Unrealized Gains	81,533	35,456
Unrealized Losses	(363)	(4,035)
Investment securities available-for-sale, at fair value	1,527,270	1,612,164
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	30,077	41,408
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(208)	(193)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	11,591	299,674
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (155)	$ (3,842)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings	30	79
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 41,668	$ 341,082
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(363)	(4,035)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Available-for-sale, Amortized Cost - Total debt securities	1,446,100	1,580,743
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale	1,527,270	1,612,164
Agency CMBS [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	1,024,133	587,974
Unrealized Gains	27,621	513
Unrealized Losses	0	(6,935)
Investment securities available-for-sale, at fair value	1,051,754	581,552
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months		174,406
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(1,137)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer		357,717
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		$ (5,798)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings		34
Debt Securities, Available-for-sale, Unrealized Loss Position		$ 532,123
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss		(6,935)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Available-for-sale, Amortized Cost - Total debt securities	1,024,133	587,974
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale	1,051,754	581,552
Non-agency CMBS [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	464,071	432,085
Unrealized Gains	794	38
Unrealized Losses	(9,840)	(252)
Investment securities available-for-sale, at fair value	455,025	431,871
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	407,322	355,260
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(9,205)	(232)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	22,868	7,480
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (635)	$ (20)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings	38	29
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 430,190	$ 362,740
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(9,840)	(252)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Available-for-sale, Amortized Cost - Total debt securities	464,071	432,085
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale	455,025	431,871
CLO [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	85,601	92,628
Unrealized Gains	1	45
Unrealized Losses	(1,241)	(468)
Investment securities available-for-sale, at fair value	84,361	92,205
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	65,711
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(589)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	18,048	43,232
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (652)	$ (468)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings	4	2
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 83,759	$ 43,232
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(1,241)	(468)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Available-for-sale, Amortized Cost - Total debt securities	85,601	92,628
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale	84,361	92,205
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Abstract]
Amortized Cost(1)	14,551	23,485
Unrealized Gains	0	0
Unrealized Losses	(2,098)	(1,245)
Investment securities available-for-sale, at fair value	12,453	22,240
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	3,892
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(371)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	8,561	22,240
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ (1,727)	$ (1,245)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | numberOfHoldings	3	4
Debt Securities, Available-for-sale, Unrealized Loss Position	$ 12,453	$ 22,240
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(2,098)	(1,245)
Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract]
Available-for-sale, Amortized Cost - Total debt securities	14,551	23,485
Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract]
Debt Securities, Available-for-sale	$ 12,453	$ 22,240

Investment Securities (Narrativ

Investment Securities (Narrative) (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Proceeds from Sale of Available-for-sale Securities			$ 8,963,000	$ 0
Available-for-sale Securities, Gross Realized Gains			8,000	0
Investment securities available-for-sale, at fair value	$ 3,304,217,000		3,304,217,000		$ 2,925,833,000
Pledged Financial Instruments, Not Separately Reported, Securities	4,000,000,000		4,000,000,000		2,700,000,000
Corporate Debt Securities [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Proceeds from Sale of Available-for-sale Securities	0	$ 0	9,000,000	$ 0
Investment securities available-for-sale, at fair value	12,453,000		12,453,000		$ 22,240,000
Callable [Member]
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Investment securities available-for-sale, at fair value	$ 1,300,000,000		$ 1,300,000,000

Loans and Leases (Detail)

Loans and Leases (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 21,852,023,000	$ 20,036,986,000	$ 19,551,646,000
Unamortized premiums	(14,100,000)	17,600,000
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	7,900,000,000
Interest receivable	56,600,000	59,000,000
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,920,116,000	12,830,177,000	12,407,968,000
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	7,124,365,000	5,296,611,000
Commercial Portfolio Segment [Member] | Asset-based
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	889,711,000	1,046,886,000
Commercial Portfolio Segment [Member] | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	6,307,567,000	5,949,339,000
Commercial Portfolio Segment [Member] | Equipment financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	598,473,000	537,341,000
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	6,931,907,000	7,206,809,000	$ 7,143,678,000
Consumer Portfolio Segment [Member] | Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	4,885,821,000	4,972,685,000
Consumer Portfolio Segment [Member] | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	1,867,969,000	2,014,544,000
Consumer Portfolio Segment [Member] | Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 178,117,000	$ 219,580,000

Loans and Leases (Narrative) (D

Loans and Leases (Narrative) (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)loan	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)loan
Operating Leased Assets [Line Items]
Total operating lease liability payments	$ 191,181		$ 191,181
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	3,400	$ 3,100	9,000	$ 8,900
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 7,800	$ 11,000	$ 10,800	$ 16,700
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | loan	0		0
Commercial Portfolio Segment [Member]
Operating Leased Assets [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | loan		4		4
Financing Receivable, Troubled Debt Restructuring, Subsequent Default		$ 3,900		$ 3,900
Commercial Portfolio Segment [Member] | Equipment financing
Operating Leased Assets [Line Items]
Net Investment in Direct Financing and Sales Type Leases	$ 235,600		$ 235,600
Total operating lease liability payments	255,900		255,900
Sales-type and Direct Financing Leases, Interest Income	$ 1,800	$ 1,200	$ 5,200	$ 4,000
Consumer Portfolio Segment [Member]
Operating Leased Assets [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | loan		1		1
Financing Receivable, Troubled Debt Restructuring, Subsequent Default		$ 100		$ 100

Loans and Leases (Allowance For

Loans and Leases (Allowance For Loan And Lease Losses By Portfolio Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 358,522	$ 211,671	$ 209,096	$ 212,353
Provision charged to expense	22,753	11,300	138,841	31,800
Charge-offs	(15,757)	(15,960)	(43,992)	(43,376)
Recoveries	4,293	2,141	8,298	8,375
Balance, end of period	358,522	211,671	209,096	212,353	$ 369,811	$ 358,522	$ 209,096	$ 209,152	$ 211,671	$ 212,353
ALLL, Individually evaluated for impairment					22,679			20,366
ALLL, Collectively evaluated for impairment					347,132			188,786
Loan and lease balances, Individually evaluated for impairment					307,907			270,631
Loan and lease balances, Collectively evaluated for impairment					21,544,116			19,281,015
Loans and leases					21,852,023		20,036,986	19,551,646
Allowance for credit losses on loans and leases							209,096
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses on loans and leases						0	57,568		0	0
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	291,520	164,344	161,669	164,073
Provision charged to expense	31,618	10,603	147,466	26,513
Charge-offs	(13,494)	(11,323)	(34,362)	(28,263)
Recoveries	2,025	176	2,872	1,477
Balance, end of period	291,520	164,344	161,669	164,073	311,669	291,520	161,669	163,800	164,344	164,073
ALLL, Individually evaluated for impairment					18,303			15,467
ALLL, Collectively evaluated for impairment					293,366			148,333
Loan and lease balances, Individually evaluated for impairment					158,324			139,129
Loan and lease balances, Collectively evaluated for impairment					14,761,792			12,268,839
Loans and leases					14,920,116		12,830,177	12,407,968
Commercial Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses on loans and leases						0	34,024		0	0
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	67,002	47,327	47,427	48,280
Provision charged to expense	(8,865)	697	(8,625)	5,287
Charge-offs	(2,263)	(4,637)	(9,630)	(15,113)
Recoveries	2,268	1,965	5,426	6,898
Balance, end of period	$ 67,002	$ 47,327	$ 47,427	$ 48,280	58,142	67,002	47,427	45,352	47,327	48,280
ALLL, Individually evaluated for impairment					4,376			4,899
ALLL, Collectively evaluated for impairment					53,766			40,453
Loan and lease balances, Individually evaluated for impairment					149,583			131,502
Loan and lease balances, Collectively evaluated for impairment					6,782,324			7,012,176
Loans and leases					$ 6,931,907		7,206,809	$ 7,143,678
Consumer Portfolio Segment [Member] | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses on loans and leases						$ 0	$ 23,544		$ 0	$ 0

Loans and Leases (Summary Of Lo

Loans and Leases (Summary Of Loan And Lease Portfolio Aging By Class Of Loan) (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	$ 184,475,000	$ 193,766,000
Financing Receivable, Nonaccrual	162,676,000	151,059,000	$ 151,059,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Financing Receivable, Not Past Due	21,667,548,000	19,843,220,000
Loans and leases	21,852,023,000	20,036,986,000	19,551,646,000
Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	12,267,000	28,545,000
Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	9,532,000	14,162,000
Commercial Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Nonaccrual	87,590,000		76,504,000
Loans and leases	14,920,116,000	12,830,177,000	12,407,968,000
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	68,943,000	62,080,000
Financing Receivable, Nonaccrual	67,849,000	59,369,000	59,369,000
Financing Receivable, Not Past Due	7,055,422,000	5,234,531,000
Loans and leases	7,124,365,000	5,296,611,000
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	1,027,000	2,094,000
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	67,000	617,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Commercial Portfolio Segment [Member] | Asset-based
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	3,760,000	139,000
Financing Receivable, Nonaccrual	3,760,000	139,000	139,000
Financing Receivable, Not Past Due	885,951,000	1,046,747,000
Loans and leases	889,711,000	1,046,886,000
Commercial Portfolio Segment [Member] | Asset-based | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	0	0
Commercial Portfolio Segment [Member] | Asset-based | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	0	0
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Commercial Portfolio Segment [Member] | Commercial real estate
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	9,129,000	13,273,000
Financing Receivable, Nonaccrual	8,799,000	11,563,000	11,563,000
Financing Receivable, Not Past Due	6,298,438,000	5,936,066,000
Loans and leases	6,307,567,000	5,949,339,000
Commercial Portfolio Segment [Member] | Commercial real estate | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	330,000	1,256,000
Commercial Portfolio Segment [Member] | Commercial real estate | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	0	454,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Commercial Portfolio Segment [Member] | 6172 Finance Lessors
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	9,915,000	11,218,000
Financing Receivable, Nonaccrual	7,182,000	5,433,000	5,433,000
Financing Receivable, Not Past Due	588,558,000	526,123,000
Loans and leases	598,473,000	537,341,000
Commercial Portfolio Segment [Member] | 6172 Finance Lessors | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	183,000	5,493,000
Commercial Portfolio Segment [Member] | 6172 Finance Lessors | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	2,550,000	292,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Nonaccrual	75,086,000		74,555,000
Loans and leases	6,931,907,000	7,206,809,000	7,143,678,000
Consumer Portfolio Segment [Member] | Residential
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	50,819,000	56,800,000
Financing Receivable, Nonaccrual	41,554,000	43,193,000	43,193,000
Financing Receivable, Not Past Due	4,835,002,000	4,915,885,000
Loans and leases	4,885,821,000	4,972,685,000
Consumer Portfolio Segment [Member] | Residential | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	4,478,000	7,166,000
Consumer Portfolio Segment [Member] | Residential | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	4,787,000	6,441,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Consumer Portfolio Segment [Member] | Home equity
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	39,605,000	43,988,000
Financing Receivable, Nonaccrual	32,853,000	30,170,000	$ 30,170,000
Financing Receivable, Not Past Due	1,828,364,000	1,970,556,000
Loans and leases	1,867,969,000	2,014,544,000
Consumer Portfolio Segment [Member] | Home equity | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	5,180,000	8,267,000
Consumer Portfolio Segment [Member] | Home equity | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	1,572,000	5,551,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	0	0
Consumer Portfolio Segment [Member] | Other consumer
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	2,304,000	6,268,000
Financing Receivable, Nonaccrual	679,000	1,192,000
Financing Receivable, Not Past Due	175,813,000	213,312,000
Loans and leases	178,117,000	219,580,000
Consumer Portfolio Segment [Member] | Other consumer | Financial Asset, 30 to 59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	1,069,000	4,269,000
Consumer Portfolio Segment [Member] | Other consumer | Financial Asset, 60 to 89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Financing Receivable, Past Due	556,000	807,000
Financing Receivable, 90 Days or More Past Due, Still Accruing	$ 0	$ 0

Loans and Leases Nonaccrual (De

Loans and Leases Nonaccrual (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	$ 162,676	$ 151,059	$ 151,059
Financing Receivable, Nonaccrual, No Allowance	73,770		54,926
Commercial Portfolio Segment [Member]
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	87,590		76,504
Financing Receivable, Nonaccrual, No Allowance	17,524		20,460
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	67,849	59,369	59,369
Financing Receivable, Nonaccrual, No Allowance	12,136		13,584
Commercial Portfolio Segment [Member] | Asset-based
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	3,760	139	139
Financing Receivable, Nonaccrual, No Allowance	0		0
Commercial Portfolio Segment [Member] | Commercial real estate
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	8,799	11,563	11,563
Financing Receivable, Nonaccrual, No Allowance	2,729		4,717
Commercial Portfolio Segment [Member] | 6172 Finance Lessors
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	7,182	5,433	5,433
Financing Receivable, Nonaccrual, No Allowance	2,659		2,159
Consumer Portfolio Segment [Member]
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	75,086		74,555
Financing Receivable, Nonaccrual, No Allowance	56,246		34,466
Consumer Portfolio Segment [Member] | Residential
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	41,554	43,193	43,193
Financing Receivable, Nonaccrual, No Allowance	30,234		19,271
Consumer Portfolio Segment [Member] | Home equity
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	32,853	$ 30,170	30,170
Financing Receivable, Nonaccrual, No Allowance	25,981		15,195
Consumer Portfolio Segment [Member] | Other consumer
Financing Receivable, Nonaccrual [Line Items]
Financing Receivable, Nonaccrual	679		1,192
Financing Receivable, Nonaccrual, No Allowance	$ 31		$ 0

Loans and Leases (Credit Qualit

Loans and Leases (Credit Quality Indicators) (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	$ 4,380,634,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	3,914,047,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,885,605,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,893,705,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,646,365,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	3,892,748,000
Financing Receivable, Revolving	3,238,919,000
Loans and leases	21,852,023,000	$ 20,036,986,000	$ 19,551,646,000
Commercial Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	3,402,320,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,934,793,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,583,813,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,378,907,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	993,046,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,832,267,000
Financing Receivable, Revolving	1,794,970,000
Loans and leases	14,920,116,000	12,830,177,000	12,407,968,000
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,521,752,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,263,403,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,102,460,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	629,520,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	288,790,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	333,204,000
Financing Receivable, Revolving	985,236,000
Loans and leases	7,124,365,000	5,296,611,000
Commercial Portfolio Segment [Member] | Asset-based
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	14,848,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	23,521,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	23,395,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	11,635,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	11,039,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	23,645,000
Financing Receivable, Revolving	781,628,000
Loans and leases	889,711,000	1,046,886,000
Commercial Portfolio Segment [Member] | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	647,350,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,484,973,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,367,931,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	701,567,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	634,155,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,443,485,000
Financing Receivable, Revolving	28,106,000
Loans and leases	6,307,567,000	5,949,339,000
Commercial Portfolio Segment [Member] | Equipment financing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	218,370,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	162,896,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	90,027,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	36,185,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	59,062,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	31,933,000
Financing Receivable, Revolving	0
Loans and leases	598,473,000	537,341,000
Commercial Portfolio Segment [Member] | (1) - (6) Pass [Member] | Commercial non-mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,519,566,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,156,057,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,013,841,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	553,942,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	257,230,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	297,765,000
Financing Receivable, Revolving	912,007,000
Loans and leases	6,710,408,000
Commercial Portfolio Segment [Member] | (1) - (6) Pass [Member] | Asset-based
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	14,848,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	21,854,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	22,595,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	11,635,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	11,039,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	22,667,000
Financing Receivable, Revolving	714,476,000
Loans and leases	819,114,000
Commercial Portfolio Segment [Member] | (1) - (6) Pass [Member] | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	646,507,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,473,602,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,296,427,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	605,375,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	595,915,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,329,377,000
Financing Receivable, Revolving	28,106,000
Loans and leases	5,975,309,000
Commercial Portfolio Segment [Member] | (1) - (6) Pass [Member] | Equipment financing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	203,498,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	144,384,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	75,993,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	31,921,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	52,328,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	26,319,000
Financing Receivable, Revolving	0
Loans and leases	534,443,000
Commercial Portfolio Segment [Member] | (7) Special Mention [Member] | Commercial non-mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	817,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	73,688,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	20,314,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	341,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	8,422,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	2,302,000
Financing Receivable, Revolving	21,233,000
Loans and leases	127,117,000
Commercial Portfolio Segment [Member] | (7) Special Mention [Member] | Asset-based
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	1,667,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	800,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	978,000
Financing Receivable, Revolving	63,392,000
Loans and leases	66,837,000
Commercial Portfolio Segment [Member] | (7) Special Mention [Member] | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	22,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	10,382,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	48,409,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	27,364,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	35,796,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	76,243,000
Financing Receivable, Revolving	0
Loans and leases	198,216,000
Commercial Portfolio Segment [Member] | (7) Special Mention [Member] | Equipment financing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	12,492,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	13,014,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	8,471,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,834,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,932,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	788,000
Financing Receivable, Revolving	0
Loans and leases	38,531,000
Commercial Portfolio Segment [Member] | (8) Substandard [Member] | Commercial non-mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,369,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	33,658,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	68,305,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	75,071,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	23,138,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	33,137,000
Financing Receivable, Revolving	51,996,000
Loans and leases	286,674,000
Commercial Portfolio Segment [Member] | (8) Substandard [Member] | Asset-based
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	3,760,000
Loans and leases	3,760,000
Commercial Portfolio Segment [Member] | (8) Substandard [Member] | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	821,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	989,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	23,095,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	68,828,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	2,444,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	37,865,000
Financing Receivable, Revolving	0
Loans and leases	134,042,000
Commercial Portfolio Segment [Member] | (8) Substandard [Member] | Equipment financing
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,380,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	5,498,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	5,563,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	2,430,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	4,802,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	4,826,000
Financing Receivable, Revolving	0
Loans and leases	25,499,000
Commercial Portfolio Segment [Member] | (9) Doubtful [Member] | Commercial non-mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	166,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Loans and leases	166,000
Consumer Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	978,314,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	979,254,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	301,792,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	514,798,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	653,319,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	2,060,481,000
Financing Receivable, Revolving	1,443,949,000
Loans and leases	6,931,907,000	7,206,809,000	$ 7,143,678,000
Consumer Portfolio Segment [Member] | Residential
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	886,328,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	856,271,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	202,336,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	464,072,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	606,615,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,870,199,000
Financing Receivable, Revolving	0
Loans and leases	4,885,821,000	4,972,685,000
Consumer Portfolio Segment [Member] | Residential | 800+
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	253,913,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	314,759,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	69,592,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	205,691,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	316,264,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	905,892,000
Financing Receivable, Revolving	0
Loans and leases	2,066,111,000
Consumer Portfolio Segment [Member] | Residential | 740-799
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	458,499,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	355,548,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	81,018,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	164,777,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	194,784,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	516,385,000
Financing Receivable, Revolving	0
Loans and leases	1,771,011,000
Consumer Portfolio Segment [Member] | Residential | 670 to 739
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	161,600,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	144,798,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	43,790,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	77,823,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	80,481,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	283,164,000
Financing Receivable, Revolving	0
Loans and leases	791,656,000
Consumer Portfolio Segment [Member] | Residential | 580-669
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	12,316,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	19,803,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	7,260,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	12,010,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	11,836,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	102,055,000
Financing Receivable, Revolving	0
Loans and leases	165,280,000
Consumer Portfolio Segment [Member] | Residential | 579 and below
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	21,363,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	676,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	3,771,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	3,250,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	62,703,000
Financing Receivable, Revolving	0
Loans and leases	91,763,000
Consumer Portfolio Segment [Member] | Home equity
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	55,976,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	47,195,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	66,041,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	43,830,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	44,182,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	188,840,000
Financing Receivable, Revolving	1,421,905,000
Loans and leases	1,867,969,000	$ 2,014,544,000
Consumer Portfolio Segment [Member] | Home equity | 800+
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	22,727,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	17,095,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	27,269,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	18,031,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	19,328,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	66,906,000
Financing Receivable, Revolving	564,318,000
Loans and leases	735,674,000
Consumer Portfolio Segment [Member] | Home equity | 740-799
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	20,580,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	16,472,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	23,739,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	11,659,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	12,765,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	49,507,000
Financing Receivable, Revolving	446,759,000
Loans and leases	581,481,000
Consumer Portfolio Segment [Member] | Home equity | 670 to 739
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	12,122,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	10,847,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	10,808,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	10,506,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	9,290,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	45,013,000
Financing Receivable, Revolving	285,776,000
Loans and leases	384,362,000
Consumer Portfolio Segment [Member] | Home equity | 580-669
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	447,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	2,257,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	3,346,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	2,297,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,964,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	19,707,000
Financing Receivable, Revolving	91,009,000
Loans and leases	121,027,000
Consumer Portfolio Segment [Member] | Home equity | 579 and below
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	100,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	524,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	879,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,337,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	835,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	7,707,000
Financing Receivable, Revolving	34,043,000
Loans and leases	45,425,000
Consumer Portfolio Segment [Member] | Consumer Loan
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	36,010,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	75,788,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	33,415,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	6,896,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	2,522,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,442,000
Financing Receivable, Revolving	22,044,000
Loans and leases	178,117,000
Consumer Portfolio Segment [Member] | Consumer Loan | 800+
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,345,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	3,436,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,901,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	581,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	115,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	173,000
Financing Receivable, Revolving	6,851,000
Loans and leases	14,402,000
Consumer Portfolio Segment [Member] | Consumer Loan | 740-799
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	10,419,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	17,858,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	9,665,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,491,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	503,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	344,000
Financing Receivable, Revolving	6,402,000
Loans and leases	46,682,000
Consumer Portfolio Segment [Member] | Consumer Loan | 670 to 739
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	21,089,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	49,734,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	19,855,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	4,158,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,616,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	520,000
Financing Receivable, Revolving	5,676,000
Loans and leases	102,648,000
Consumer Portfolio Segment [Member] | Consumer Loan | 580-669
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,440,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	4,247,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,744,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	600,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	253,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	180,000
Financing Receivable, Revolving	1,623,000
Loans and leases	11,087,000
Consumer Portfolio Segment [Member] | Consumer Loan | 579 and below
Financing Receivable, Credit Quality Indicator [Line Items]
Financing Receivable, Originated in Current Fiscal Year	717,000
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	513,000
Financing Receivable, Originated Two Years before Latest Fiscal Year	250,000
Financing Receivable, Originated Three Years before Latest Fiscal Year	66,000
Financing Receivable, Originated Four Years before Latest Fiscal Year	35,000
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	225,000
Financing Receivable, Revolving	1,492,000
Loans and leases	$ 3,298,000

Loans and Leases (Impaired Loan

Loans and Leases (Impaired Loans And Leases By Class) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	$ 421,885
Amortized Cost	307,907	$ 256,410
Amortized Cost No Allowance	144,239
Amortized Cost With Allowance	163,668
Related Valuation Allowance	22,679
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	160,667	140,096
Amortized Cost	125,799	102,254
Amortized Cost No Allowance	28,937	29,739
Amortized Cost With Allowance	96,862	72,515
Related Valuation Allowance	15,833	7,862
Commercial Portfolio Segment [Member] | Asset-based
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	4,114	465
Amortized Cost	3,760	139
Amortized Cost No Allowance	0	0
Amortized Cost With Allowance	3,760	139
Related Valuation Allowance	459	5
Commercial Portfolio Segment [Member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	24,865	29,292
Amortized Cost	21,583	23,297
Amortized Cost No Allowance	12,679	14,818
Amortized Cost With Allowance	8,904	8,479
Related Valuation Allowance	1,613	1,143
Commercial Portfolio Segment [Member] | Equipment financing
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	7,661	5,591
Amortized Cost	7,182	5,433
Amortized Cost No Allowance	2,659	2,159
Amortized Cost With Allowance	4,523	3,274
Related Valuation Allowance	398	418
Commercial Portfolio Segment [Member] | Residential
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance		98,790
Amortized Cost		90,096
Amortized Cost No Allowance		56,231
Amortized Cost With Allowance		33,865
Related Valuation Allowance		3,618
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance		312,737
Amortized Cost		256,410
Amortized Cost No Allowance		130,619
Amortized Cost With Allowance		125,791
Related Valuation Allowance		14,249
Consumer Portfolio Segment [Member] | Residential
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	110,542
Amortized Cost	100,443	90,096
Amortized Cost No Allowance	63,457
Amortized Cost With Allowance	36,986
Related Valuation Allowance	3,293
Consumer Portfolio Segment [Member] | Home equity
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	111,715	38,503
Amortized Cost	48,461	35,191
Amortized Cost No Allowance	36,477	27,672
Amortized Cost With Allowance	11,984	7,519
Related Valuation Allowance	1,012	1,203
Consumer Portfolio Segment [Member] | Consumer Loan
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	2,321	0
Amortized Cost	679	0
Amortized Cost No Allowance	30	0
Amortized Cost With Allowance	649	0
Related Valuation Allowance	$ 71	$ 0

Loans and Leases (Interest Inco

Loans and Leases (Interest Income From Impaired Loans And Leases, By Class) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 315,533	$ 261,939	$ 282,161	$ 264,982
Accrued Interest Income	2,202	1,920	6,773	6,194
Cash Basis Interest Income	586	517	2,689	1,584
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	127,676	102,996	114,027	103,772
Accrued Interest Income	954	751	2,882	2,515
Cash Basis Interest Income	0	0	0	0
Commercial Portfolio Segment [Member] | Asset-based
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	1,949	4,673	1,950	4,694
Accrued Interest Income	0	0	0	0
Cash Basis Interest Income	0	0	0	0
Commercial Portfolio Segment [Member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	24,555	15,051	22,440	13,526
Accrued Interest Income	192	60	507	194
Cash Basis Interest Income	0	0	0	0
Commercial Portfolio Segment [Member] | Equipment financing
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	7,488	4,718	6,308	5,901
Accrued Interest Income	0	0	0	0
Cash Basis Interest Income	0	0	0	0
Consumer Portfolio Segment [Member] | Residential
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	103,608	97,917	95,270	99,599
Accrued Interest Income	741	862	2,352	2,682
Cash Basis Interest Income	289	271	1,149	817
Consumer Portfolio Segment [Member] | Home equity
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	49,309	36,584	41,826	37,490
Accrued Interest Income	302	247	1,002	803
Cash Basis Interest Income	297	246	1,540	767
Consumer Portfolio Segment [Member] | Consumer Loan
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	948	0	340	0
Accrued Interest Income	13	0	30	0
Cash Basis Interest Income	$ 0	$ 0	$ 0	$ 0

Loans and Leases Impaired Colla

Loans and Leases Impaired Collateral (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 307,907	$ 256,410
Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	91,281	59,550
Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	216,626	196,860
Collateral Value
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	135,300	109,800
Commercial Portfolio Segment [Member] | Commercial non-mortgage
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	125,799	102,254
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	11,337	10,682
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	114,462	91,572
Commercial Portfolio Segment [Member] | Asset-based
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	3,760	139
Commercial Portfolio Segment [Member] | Asset-based | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	0	0
Commercial Portfolio Segment [Member] | Asset-based | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	3,760	139
Commercial Portfolio Segment [Member] | Commercial real estate
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	21,583	23,297
Commercial Portfolio Segment [Member] | Commercial real estate | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	15,708	14,097
Commercial Portfolio Segment [Member] | Commercial real estate | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	5,875	9,200
Commercial Portfolio Segment [Member] | Equipment financing
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	7,182	5,433
Commercial Portfolio Segment [Member] | Equipment financing | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	0	0
Commercial Portfolio Segment [Member] | Equipment financing | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	7,182	5,433
Commercial Portfolio Segment [Member] | Residential
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment		90,096
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment		256,410
Consumer Portfolio Segment [Member] | Residential
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	100,443	90,096
Consumer Portfolio Segment [Member] | Residential | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	35,379	17,635
Consumer Portfolio Segment [Member] | Residential | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	65,064	72,461
Consumer Portfolio Segment [Member] | Home equity
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	48,461	35,191
Consumer Portfolio Segment [Member] | Home equity | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	28,857	17,136
Consumer Portfolio Segment [Member] | Home equity | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	19,604	18,055
Consumer Portfolio Segment [Member] | Consumer Loan
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	679	0
Consumer Portfolio Segment [Member] | Consumer Loan | Collateral Pledged
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	0	0
Consumer Portfolio Segment [Member] | Consumer Loan | Uncollateralized
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 679	$ 0

Loans and Leases (Summary Of Th

Loans and Leases (Summary Of The Recorded Investment Of Company's TDRs) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	$ 245,294		$ 237,438
Specific reserves for TDRs included in the balance of ACL on loans and leases	369,811	$ 358,522	209,096	$ 209,152	$ 211,671	$ 212,353
Additional funds committed to borrowers in TDR status	15,345		4,856
Performing Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	143,544		136,449
Nonperforming Financial Instruments [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	101,750		100,989
Nonperforming Financial Instruments [Member] | Troubled Debt Restructures [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Specific reserves for TDRs included in the balance of ACL on loans and leases	$ 17,092		$ 12,956

Loans and Leases (Information o

Loans and Leases (Information on How Loans and Leases were Modified as a TDR) (Detail) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)loan	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	30	28	170	105
Post-Modification Recorded Investment | $	$ 1,958	$ 34,249	$ 53,617	$ 76,335
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	0	2	6	8
Post-Modification Recorded Investment | $	$ 0	$ 29	$ 507	$ 222
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Contractual Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	0	1	0	2
Post-Modification Recorded Investment | $	$ 0	$ 12	$ 0	$ 112
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Maturity/Rate Combined [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	2	3	7	6
Post-Modification Recorded Investment | $	$ 333	$ 225	$ 607	$ 296
Commercial Portfolio Segment [Member] | Commercial non-mortgage | Other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	1	6	24	25
Post-Modification Recorded Investment | $	$ 6	$ 30,586	$ 40,128	$ 64,642
Commercial Portfolio Segment [Member] | Commercial real estate | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	0	0	1	0
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 72	$ 0
Commercial Portfolio Segment [Member] | Commercial real estate | Maturity/Rate Combined [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	0	0	1	0
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 278	$ 0
Commercial Portfolio Segment [Member] | Commercial real estate | Other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	3	1	3	3
Post-Modification Recorded Investment | $	$ 306	$ 2,180	$ 306	$ 4,816
Consumer Portfolio Segment [Member] | Residential | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	1	1	3	5
Post-Modification Recorded Investment | $	$ 134	$ 67	$ 485	$ 1,007
Consumer Portfolio Segment [Member] | Residential | Maturity/Rate Combined [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	4	1	9	14
Post-Modification Recorded Investment | $	$ 425	$ 368	$ 1,123	$ 2,216
Consumer Portfolio Segment [Member] | Residential | Other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	2	2	22	6
Post-Modification Recorded Investment | $	$ 202	$ 243	$ 3,877	$ 785
Consumer Portfolio Segment [Member] | Home equity | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	1	1	3	5
Post-Modification Recorded Investment | $	$ 31	$ 134	$ 188	$ 504
Consumer Portfolio Segment [Member] | Home equity | Maturity/Rate Combined [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	1	2	2	4
Post-Modification Recorded Investment | $	$ 15	$ 30	$ 28	$ 140
Consumer Portfolio Segment [Member] | Home equity | Other [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Loans and Leases | loan	15	8	89	27
Post-Modification Recorded Investment | $	$ 506	$ 375	$ 6,018	$ 1,595

Loans and Leases (Investments i

Loans and Leases (Investments in TDRs, Segregated by Risk Rating Exposure) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	$ 245,294	$ 237,438
Commercial Portfolio Segment [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	124,370	112,152
Commercial Portfolio Segment [Member] | (1) - (6) Pass [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	12,591	3,952
Commercial Portfolio Segment [Member] | (7) Special Mention [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	0	63
Commercial Portfolio Segment [Member] | (8) Substandard [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	111,613	104,277
Commercial Portfolio Segment [Member] | (9) Doubtful [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment of TDRs	$ 166	$ 3,860

Transfers of Financial Assets_2

Transfers of Financial Assets (Reserve for loan repurchases) (Detail) - SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 655	$ 684	$ 508	$ 674
Provision charged to expense	50	19	99	1,839
(Charge-offs/settlements, net) recoveries, net	0	(7)	98	(1,817)
Ending balance	$ 705	$ 696	$ 705	$ 696

Transfers of Financial Assets_3

Transfers of Financial Assets (Loans sold) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net gain on sale	$ 7,087	$ 2,133	$ 14,185	$ 3,829
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Ancillary fees	1,018	470	2,243	1,051
Consumer Portfolio Segment [Member] | Residential Mortgage Loans Servicing Retained [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale	164,054	60,493	325,832	117,306
Consumer Portfolio Segment [Member] | Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale	172,579	66,236	342,747	129,700
Net gain on sale	6,244	1,652	11,587	2,510
Fair value option adjustment	$ (175)	$ 11	$ 355	$ 268

Transfers of Financial Assets_4

Transfers of Financial Assets (Mortgage Servicing Assets) (Narrative) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Proceeds of Other Loans and Leases Held-for-investment			$ 6,414	$ 20,542
Mortgage banking activities	$ 7,087	$ 2,133	14,185	3,829
Residential
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Proceeds of Other Loans and Leases Held-for-investment			6,400	4,000
Contractually Specified Servicing Fees, Amount	1,100			1,400
Commercial Loan [Member]
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Proceeds of Other Loans and Leases Held-for-investment				16,600
Mortgage banking activities			295	615
Consumer Portfolio Segment [Member] | Residential
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]
Mortgage banking activities	6,244	1,652	11,587	$ 2,510
Retained servicing rights	2,400,000		$ 2,400,000		$ 2,400,000
Contractually Specified Servicing Fees, Amount	$ 300	$ 500

Transfers of Financial Assets S

Transfers of Financial Assets Servicing Assets at Amortized Cost Roll Forward (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Beginning Balance	$ 14,926	$ 18,712	$ 17,484	$ 21,215
Additions	1,301	966	3,269	2,219
Amortization	(1,616)	(1,801)	(4,992)	(5,557)
Mortgage Servicing Rights (MSR) Impairment (Recovery)	(203)	0	(1,353)	0
Ending Balance	$ 14,408	$ 17,877	$ 14,408	$ 17,877

Leases Lessee Accounting (Detai

Leases Lessee Accounting (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Right-of-Use Asset	$ 146,641
Less: Present value adjustment	$ 165,211	$ 174,396

Leases Lessee Cost (Details)

Leases Lessee Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lease, Cost [Abstract]
Operating lease costs	$ 7,381	$ 7,512	$ 22,212	$ 22,384
Variable lease costs	1,297	1,292	4,217	3,613
Sublease income	(141)	(142)	(428)	(437)
Total operating lease cost	8,537	8,662	26,001	25,560
Cash paid for amounts included in the measurement of lease liabilities	7,823	7,938	23,359	23,349
ROU lease assets obtained in exchange for new operating lease liabilities	$ 856	$ 9,983	$ 9,552	$ 22,917
Weighted-average remaining lease term - operating leases, in years	8 years 2 months 23 days		8 years 2 months 23 days
Weighted-average discount rate - operating leases	3.22%		3.22%

Leases Operating Lease Liabilit

Leases Operating Lease Liabilities, Payments, Due, Rolling Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Lessee, Operating Lease, Liability, Payment, Due, Rolling Maturity [Abstract]
Remainder of 2020	$ 5,274
2021	30,604
2022	27,099
2023	24,187
2024	21,307
Thereafter	82,710
Total operating lease liability payments	191,181
Less: Present value adjustment	165,211	$ 174,396
Lease liabilities	$ 25,970

Leases (Details)

Leases (Details)	Sep. 30, 2020
Minimum [Member]
Operating Leased Assets [Line Items]
Lessee, Operating Lease, Term of Contract	5 years
Maximum [Member]
Operating Leased Assets [Line Items]
Lessee, Operating Lease, Term of Contract	20 years

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Gross Carrying Value And Accumulated Amortization Of Other Intangible Assets) (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 47,625	$ 43,000
Accumulated Amortization	24,096	21,083
Net Carrying Amount	$ 23,529	21,917
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	9 years
Core Deposits [Member] | HSA Bank [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 26,625	22,000
Accumulated Amortization	14,875	13,073
Net Carrying Amount	11,750	8,927
Customer Relationships [Member] | HSA Bank [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	21,000	21,000
Accumulated Amortization	9,221	8,010
Net Carrying Amount	$ 11,779	$ 12,990

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Schedule Of Expected Future Amortization Expense) (Detail) $ in Thousands	Sep. 30, 2020USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2020	$ 1,146
2021	4,513
2022	4,411
2023	4,315
2024	2,084
Thereafter	$ 7,060

Deposits (Summary Of Deposits)

Deposits (Summary Of Deposits) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Non-interest-bearing:
Demand	$ 6,136,814	$ 4,446,463
Interest-bearing:
HSA	6,976,280	6,416,135
Checking	3,390,921	2,689,734
Money market	3,069,098	2,312,840
Savings	4,777,000	4,354,809
Time deposits	2,570,440	3,104,765
Total interest-bearing	20,783,739	18,878,283
Total deposits	26,920,553	23,324,746
Time deposits and interest-bearing checking, included in above balances, obtained through brokers	733,691	652,151
Time deposits, included in above balance, that exceed the FDIC limit	533,180	661,334
Deposit overdrafts reclassified as loan balances	$ 1,122	$ 1,721

Deposits (Scheduled Maturities

Deposits (Scheduled Maturities Of Time Deposits) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Deposit Liabilities [Abstract]
Remainder of 2020	$ 849,021
2021	1,468,973
2022	141,760
2023	45,774
2024	22,321
Thereafter	42,591
Time deposits	$ 2,570,440	$ 3,104,765

Borrowings Borrowings - (Narrat

Borrowings Borrowings - (Narrative) (Details) - USD ($) $ in Billions	Sep. 30, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Amount	$ 2.3	$ 3.5

Borrowings (Summary Of Securiti

Borrowings (Summary Of Securities Sold Under Agreements To Repurchase And Other Borrowings) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets Sold under Agreements to Repurchase [Line Items]
Amount	$ 2,300,000	$ 3,500,000
Securities sold under agreements to repurchase
Assets Sold under Agreements to Repurchase [Line Items]
Amount	$ 478,122	$ 440,431
Rate	0.35%	0.91%
Fed funds purchased
Assets Sold under Agreements to Repurchase [Line Items]
Amount	$ 823,700	$ 600,000
Rate	0.08%	1.59%
Securities sold under agreements to repurchase and other borrowings
Assets Sold under Agreements to Repurchase [Line Items]
Amount	$ 1,301,822	$ 1,040,431
Rate	0.18%	1.30%
Original maturity of one year or less | Securities sold under agreements to repurchase
Assets Sold under Agreements to Repurchase [Line Items]
Amount	$ 278,122	$ 240,431
Rate	0.19%	0.19%
Original maturity of greater than one year, non-callable | Securities sold under agreements to repurchase
Assets Sold under Agreements to Repurchase [Line Items]
Amount	$ 200,000	$ 200,000
Rate	0.57%	1.78%

Borrowings Borrowings (Summary

Borrowings Borrowings (Summary Of Advances Payable To the Federal Home Loan Bank) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Federal Home Loan Bank, Advances, Maturity, Rolling Year [Abstract]
FHLB advances maturing within 1 year, Total Outstanding	$ 175,000	$ 1,690,000
FHLB advances maturing after 1 but within 2 years, Total Outstanding	150,024	200,000
FHLB advances maturing after 2 but within 3 years, Total Outstanding	169	130
FHLB advances maturing after 3 but within 4 years, Total Outstanding	50,141	229
FHLB advances maturing after 4 but within 5 years, Total Outstanding	50,000	50,000
FHLB advances maturing after 5 years, Total Outstanding	7,909	8,117
Federal Home Loan Bank, Advances	$ 433,243	$ 1,948,476
Federal Home Loan Bank, Advances, Weighted Average Interest Rate [Abstract]
FHLB advances maturing within 1 year, Weighted Average Contractual Coupon Rate (as a percent)	0.88%	1.79%
FHLB advances maturing after 1 but within 2 years, Weighted Average Contractual Coupon Rate (as a percent)	1.15%	2.53%
FHLB advances maturing after 2 but within 3 years, Weighted Average Contractual Coupon Rate (as a percent)	1.73%	0.00%
FHLB advances maturing after 3 but within 4 years, Weighted Average Contractual Coupon Rate (as a percent)	1.59%	2.95%
FHLB advances maturing after 4 but within 5 years, Weighted Average Contractual Coupon Rate (as a percent)	1.42%	1.59%
FHLB advances maturing after 5 years, Weighted Average Contractual Coupon Rate (as a percent)	2.66%	2.66%
Federal Home Loan Bank, Advances, Weighted Average Contractual Coupon Rate (as a percent)	1.15%	1.87%
Aggregate carrying value of assets pledged as collateral	$ 7,561,287	$ 7,318,748
Remaining borrowing capacity	$ 4,506,213	$ 2,937,644

Borrowings (Long Term Debt) (De

Borrowings (Long Term Debt) (Details) - USD ($)	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Notes and subordinated debt	$ 572,822,000		$ 544,806,000
Debt issuance cost on senior fixed-rates	(2,729,000)		(3,030,000)
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	345,502,000		317,486,000
Long-term debt	$ 568,846,000		$ 540,364,000
Variable interest rate	3.20%		4.85%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	2.95%
Long-term Debt [Member]
Debt Instrument [Line Items]
Discount on senior fixed-rate notes	$ (1,247,000)		$ (1,412,000)
Junior subordinated debt Webster Statutory Trust I floating-rate notes due September 17, 2033 [Member]
Debt Instrument [Line Items]
Notes and subordinated debt	$ 77,320,000		77,320,000
Debt Instrument, Redemption, Period One [Member] | 4.375% Senior fixed-rate notes due February 15, 2024 [Member]
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)	4.375%
Notes and subordinated debt	$ 150,000,000		150,000,000
Debt Instrument, Redemption, Period Two [Member] | 4.375% Senior fixed-rate notes due February 15, 2024 [Member]
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)	4.10%
Notes and subordinated debt	$ 345,502,000		317,486,000
Long-term Debt [Member]
Debt Instrument [Line Items]
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	$ 45,502,000	$ 48,200,000	$ 17,486,000

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income, Net of Tax (Schedule of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 3,174,779	$ 3,065,217	$ 3,207,770	$ 2,886,515
Net current-period OCI	10,592	28,956	88,109	93,418
Ending Balance	3,219,690	3,152,394	3,219,690	3,152,394
Available For Sale and Transferred Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	63,476	(9,406)	17,251	(71,374)
OCI before reclassifications	11,766	24,304	57,997	86,272
Amounts reclassified from AOCI	0	0	(6)	0
Net current-period OCI	11,766	24,304	57,991	86,272
Ending Balance	75,242	14,898	75,242	14,898
Derivative Instruments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	20,649	(8,931)	(9,184)	(9,313)
OCI before reclassifications	(3,310)	2,216	23,655	507
Amounts reclassified from AOCI	1,398	1,387	4,266	3,478
Net current-period OCI	(1,912)	3,603	27,921	3,985
Ending Balance	18,737	(5,328)	18,737	(5,328)
Defined Benefit Pension and Other Postretirement Benefit Plans [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(42,680)	(47,853)	(44,139)	(49,965)
OCI before reclassifications	0	0	0	0
Amounts reclassified from AOCI	738	1,049	2,197	3,161
Net current-period OCI	738	1,049	2,197	3,161
Ending Balance	(41,942)	(46,804)	(41,942)	(46,804)
Accumulated Other Comprehensive Income, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	41,445	(66,190)	(36,072)	(130,652)
OCI before reclassifications	8,456	26,520	81,652	86,779
Amounts reclassified from AOCI	2,136	2,436	6,457	6,639
Net current-period OCI	10,592	28,956	88,109	93,418
Ending Balance	$ 52,037	$ (37,234)	$ 52,037	$ (37,234)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income, Net of Tax (Schedule of Accumulated Other Comprehensive Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	$ (18,289)	$ (25,411)	$ (44,235)	$ (78,003)
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	0		(2)	0
Net of tax	0	0	6	0
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] | Reclassification out of accumualted comprehensive income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Debt Securities, Available-for-sale, Gain (Loss)	0	0	8	0
Income tax expense		0
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	(1,398)	(1,387)	(4,266)	(3,478)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Reclassification out of accumualted comprehensive income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	495	503	1,510	1,223
Net of tax	(1,398)	(1,387)	(4,266)	(3,478)
Other Nonoperating Expense	(967)	(1,375)	(3,228)	(4,174)
Interest Income, Other	(926)	(515)	(2,548)	(527)
Accumulated Defined Benefit Plans Adjustment, Net Unamortized Gain (Loss) [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(1,002)	(1,421)	(2,982)	(4,280)
Defined benefit pension and postretirement benefit plans [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	(738)	(1,049)	(2,197)	(3,161)
Income tax expense	$ 264	$ 372	$ 785	$ 1,119

Regulatory Matters (Information

Regulatory Matters (Information On The Capital Ratios) (Detail)	9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital	$ 2,519,589,000		$ 2,516,361,000
Common Equity Tier One Capital Ratio	0.1123		0.1156
Common Equity Tier One Capital Required for Capital Adequacy	$ 1,009,651,000		$ 979,739,000
Common Equity Tier One Capital Required to be Well-Capitalized	1,458,385,000		1,415,179,000
Total risk-based capital, Actual Amount	$ 3,022,511,000		$ 2,950,181,000
Total risk-based capital, Actual Ratio	0.1347		0.1355
Total risk-based capital, Capital Requirements, Minimum Amount	$ 1,794,935,000		$ 1,741,758,000
Total risk-based capital, Capital Requirements, Minimum Ratio	0.080		0.080
Total risk-based capital, Capital Requirements, Well Capitalized Amount	$ 2,243,669,000		$ 2,177,198,000
Total risk-based capital, Capital Requirements, Well Capitalized Ratio	0.100		0.100
Tier 1 capital, Actual Amount	$ 2,664,626,000		$ 2,661,398,000
Tier 1 capital, Actual Ratio	0.1188		0.1222
Tier 1 capital, Capital Requirements, Minimum Amount	$ 1,346,201,000		$ 1,306,319,000
Tier 1 capital, Capital Requirements, Minimum Ratio	0.060		0.060
Tier 1 capital, Capital Requirements, Well Capitalized Amount	$ 1,794,935,000		$ 1,741,758,000
Tier 1 capital, Capital Requirements, Well Capitalized Ratio	0.080		0.080
Tier 1 leverage capital ratio, Actual Amount	$ 2,664,626,000		$ 2,661,398,000
Tier 1 leverage capital ratio, Actual Ratio	0.0824		0.0896
Tier 1 leverage capital ratio, Capital Requirements, Minimum Amount	$ 1,293,186,000		$ 1,188,507,000
Tier 1 leverage capital ratio, Capital Requirements, Minimum Ratio	0.040		0.040
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Amount	$ 1,616,482,000		$ 1,485,634,000
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Ratio	0.050		0.050
Dividends paid	$ 0	$ 170,000,000
Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier One Capital	$ 2,744,235,000		$ 2,527,645,000
Common Equity Tier One Capital Ratio	0.1224		0.1161
Common Equity Tier One Capital Required for Capital Adequacy	$ 1,009,277,000		$ 979,497,000
Common Equity Tier One Capital Required to be Well-Capitalized	1,457,845,000		1,414,829,000
Total risk-based capital, Actual Amount	$ 3,024,694,000		$ 2,739,108,000
Total risk-based capital, Actual Ratio	0.1349		0.1258
Total risk-based capital, Capital Requirements, Minimum Amount	$ 1,794,270,000		$ 1,741,328,000
Total risk-based capital, Capital Requirements, Minimum Ratio	0.080		0.080
Total risk-based capital, Capital Requirements, Well Capitalized Amount	$ 2,242,838,000		$ 2,176,660,000
Total risk-based capital, Capital Requirements, Well Capitalized Ratio	0.100		0.100
Tier 1 capital, Actual Amount	$ 2,744,235,000		$ 2,527,645,000
Tier 1 capital, Actual Ratio	0.1224		0.1161
Tier 1 capital, Capital Requirements, Minimum Amount	$ 1,345,703,000		$ 1,305,996,000
Tier 1 capital, Capital Requirements, Minimum Ratio	0.060		0.060
Tier 1 capital, Capital Requirements, Well Capitalized Amount	$ 1,794,270,000		$ 1,741,328,000
Tier 1 capital, Capital Requirements, Well Capitalized Ratio	0.080		0.080
Tier 1 leverage capital ratio, Actual Amount	$ 2,744,235,000		$ 2,527,645,000
Tier 1 leverage capital ratio, Actual Ratio	0.0849		0.0851
Tier 1 leverage capital ratio, Capital Requirements, Minimum Amount	$ 1,292,763,000		$ 1,187,953,000
Tier 1 leverage capital ratio, Capital Requirements, Minimum Ratio	0.040		0.040
Tier 1 leverage capital ratio, Capital Requirements, Well Capitalized Amount	$ 1,615,954,000		$ 1,484,941,000
Tier 1 leverage capital ratio, 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

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	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings for basic and diluted earnings per common share:
Net income	$ 69,281	$ 93,865	$ 160,577	$ 292,250
Less: Preferred stock dividends	1,968	1,968	5,906	5,906
Undistributed Earnings, Basic	67,313	91,897	154,671	286,344
Undistributed Earnings, Diluted, Total	67,313	91,897	154,671	286,344
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic	423	455	913	1,425
Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted	423	455	913	1,425
Earnings applicable to common shareholders	66,890	91,442	153,758	284,919
Earnings applicable to common shareholders	$ 66,890	$ 91,442	$ 153,758	$ 284,919
Shares:
Weighted-average common shares outstanding - basic	89,630	91,559	90,076	91,554
Effect of dilutive securities	108	315	159	329
Weighted-average common shares outstanding - diluted	89,738	91,874	90,235	91,883
Earnings per common share (1):
Basic	$ 0.75	$ 1	$ 1.71	$ 3.11
Diluted	$ 0.75	$ 1	$ 1.70	$ 3.10

Earnings Per Common Share Sched

Earnings Per Common Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Narrative (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restricted stock (due to performance conditions on non-participating shares) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	96	44	125	69

Derivative Financial Instrume_3

Derivative Financial Instruments (Schedule fair value of derivative instruments) (Detail) - USD ($)	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	$ 6,009,067,000		$ 6,198,556,000
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	388,439,000		146,037,000
Derivative Asset, Fair Value, Amount Offset Against Collateral	12,390,000		4,779,000
Asset Derivatives, Fair Value, Less: Cash collateral posted	32,159,000		8,100,000
Gross derivative instruments, before netting (1)	343,890,000		133,158,000
Liability Derivatives, Notional Amount	4,882,080,000		4,722,801,000
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	18,247,000		13,813,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	12,390,000		4,779,000
Liability Derivatives, Fair Value, Less: Cash collateral posted	5,085,000		1,871,000
Derivative liability	772,000		7,163,000
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	345,502,000		317,486,000
Long-term Debt [Member]
Derivatives, Fair Value [Line Items]
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	45,502,000	$ 48,200,000	17,486,000
CME [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value, Less: Cash collateral posted	82,800,000
Gross derivative instruments, before netting (1)	0
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	44,549,000		13,012,000
Derivative Asset, Fair Value, Amount Offset Against Collateral	44,549,000		12,879,000
Gross derivative instruments, before netting (1)	0		133,000
Derivative Liability, Fair Value, Gross Liability	17,568,000		6,710,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	17,475,000		6,650,000
Derivative liability	93,000		60,000
Designated as Hedging Instrument [Member] | Interest rate derivatives [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	1,150,000,000		1,225,000,000
Derivative Asset, Fair Value, Gross Asset	44,114,000		11,855,000
Liability Derivatives, Notional Amount	25,000,000		300,000,000
Derivative Liability, Fair Value, Gross Liability	145,000		3,153,000
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	4,859,067,000		4,973,556,000
Asset Derivatives, Fair Value, Positions not subject to master netting agreement	344,325,000		134,182,000
Liability Derivatives, Notional Amount	4,857,080,000		4,422,801,000
Liability Derivatives, Fair Value, Positions not subject to master netting agreement	18,102,000		10,660,000
Not Designated as Hedging Instrument [Member] | Interest Rate Swap, CME [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	60,100,000		1,100,000,000
Liability Derivatives, Notional Amount	3,400,000,000		2,600,000,000
Not Designated as Hedging Instrument [Member] | Interest rate derivatives [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	4,642,373,000		4,869,139,000
Derivative Asset, Fair Value, Gross Asset	341,275,000		133,455,000
Liability Derivatives, Notional Amount	4,505,792,000		4,090,522,000
Derivative Liability, Fair Value, Gross Liability	17,212,000		9,732,000
Not Designated as Hedging Instrument [Member] | Credit Risk Contract [Member] | RPA-Out [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	95,400,000		65,700,000
Not Designated as Hedging Instrument [Member] | Credit Risk Contract [Member] | RPA-In [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Notional Amount	317,800,000		223,400,000
Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member] | RPA-Out [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	105,605,000		27,873,000
Derivative Asset, Fair Value, Gross Asset	2,717,000		329,000
Not Designated as Hedging Instrument [Member] | Mortgage Banking Derivatives [Member] | RPA-In [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Notional Amount	0		57,000,000
Derivative Liability, Fair Value, Gross Liability	0		110,000
Not Designated as Hedging Instrument [Member] | Other Contract [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Amounts	111,089,000		76,544,000
Derivative Asset, Fair Value, Gross Asset	333,000		398,000
Liability Derivatives, Notional Amount	351,288,000		275,279,000
Derivative Liability, Fair Value, Gross Liability	890,000		$ 818,000
Interest Rate Lock Commitments [Member]
Derivatives, Fair Value [Line Items]
Other Commitment	$ 10,800,000

Derivative Financial Instrume_4

Derivative Financial Instruments (Schedule of the changes in the fair value of non-hedge accounting derivatives) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ 3,467	$ 2,810		$ 7,605
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings			$ 9,393
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	3,824	784	7,227	5,906
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	872	347	2,498	96
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	(1,229)	1,679	(332)	1,603
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	0	0	0	0
Fair Value Hedging [Member] | Operating Expense [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	0	(10,624)	(30,693)	(26,436)
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(1,505)	1,610	(253)	3,555
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	1,152	1,095	3,501	3,028
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	(2,657)	515	(3,754)	527
Long-term Debt [Member] | Fair Value Hedging [Member] | Operating Expense [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ 0	$ 10,624	$ 30,693	$ 26,436

Derivative Financial Instrume_5

Derivative Financial Instruments (AOCI Related to Cash Flow Hedges) (Narrative) (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Components Excluded from Assessment of Interest Rate Cash Flow Hedge Effectiveness	$ 10
Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Estimate of amount to be reclassified from AOCL	(1.9)
Remaining unamortized gain (loss) on termination of cash flow hedges	(3.1)
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Estimate of amount to be reclassified from AOCL	$ (8.1)

Derivative Financial Instrume_6

Derivative Financial Instruments (Offsetting Derivatives) (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative instrument asset, Amount Offset, Total	$ (12,390,000)	$ (4,779,000)
Derivative instrument asset, Amount Offset	32,159,000	8,100,000
Gross derivative instruments, before netting (1)	343,890,000	133,158,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	12,390,000	4,779,000
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	(5,085,000)	(1,871,000)
Derivative liability	772,000	7,163,000
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(196,000)	(299,000)
Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	(196,000)	(432,000)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(1,041,000)	(329,000)
Derivative Liability, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	(1,134,000)	(389,000)
Hedge Accounting Positions [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	44,549,000	13,012,000
Derivative instrument asset, Amount Offset, Total	(44,549,000)	(12,879,000)
Gross derivative instruments, before netting (1)	0	133,000
Derivative Liability, Fair Value, Gross Liability	17,568,000	6,710,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	17,475,000	6,650,000
Derivative liability	93,000	60,000
CME [Member]
Derivative [Line Items]
Derivative instrument asset, Amount Offset	82,800,000
Gross derivative instruments, before netting (1)	0
Interest Rate Derivatives [Member] | Hedge Accounting Positions [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	44,114,000	11,855,000
Derivative Liability, Fair Value, Gross Liability	$ 145,000	$ 3,153,000

Derivative Financial Instrume_7

Derivative Financial Instruments Impact of Fair Value on Qualifying Hedges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	$ 3,467	$ 2,810		$ 7,605
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	345,502		$ 345,502			$ 317,486
Designated as Hedging Instrument [Member] | Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	0	0	0	0
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Fair Value Hedges Recognized in Earnings	(1,505)	1,610	(253)	3,555
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	0	(10,624)	(30,693)	(26,436)
Long-term Debt [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease)	45,502		45,502		$ 48,200	$ 17,486
Long-term Debt [Member] | 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	$ 0	$ 10,624	$ 30,693	$ 26,436

Derivative Financial Instrume_8

Derivative Financial Instruments (Counterparty Credit Risk Narrative) (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Maximum Length of Time Hedged in Cash Flow Hedge	4 years
Derivative instrument asset, Amount Offset	$ 32,159	$ 8,100
Derivative, Collateral, Right to Reclaim Cash	349,500
Credit Derivative, Maximum Exposure, Undiscounted	346,100
Derivative Credit Risk Valuation Adjustment, Derivative Assets (Liabilities)	4,200
Cash and Due from Banks [Member]
Derivative [Line Items]
Derivative, Collateral, Right to Reclaim Cash	33,200
Valuation, Market Approach [Member]
Derivative [Line Items]
Credit Derivative, Maximum Exposure, Undiscounted	40,000
CME [Member]
Derivative [Line Items]
Derivative instrument asset, Amount Offset	82,800
Derivative, Collateral, Right to Reclaim Cash	$ 294,600

Derivative Financial Instrume_9

Derivative Financial Instruments Schedule of Fair Value Hedging Instruments, Statements of Financial Performance and Financial Position, Location (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative Asset, Fair Value, Amount Offset Against Collateral	$ 12,390	$ 4,779
Derivative Asset	343,890	133,158
Derivative Liability, Fair Value, Amount Offset Against Collateral	12,390	4,779
Derivative Liability	772	7,163
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	196	299
Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	196	432
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	1,041	329
Derivative Liability, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	1,134	389
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Liability, Fair Value, Gross Liability	17,568	6,710
Derivative Asset, Fair Value, Gross Asset	44,549	13,012
Derivative Asset, Fair Value, Amount Offset Against Collateral	44,549	12,879
Derivative Asset	0	133
Derivative Liability, Fair Value, Amount Offset Against Collateral	17,475	6,650
Derivative Liability	$ 93	$ 60

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage Loans in Process of Foreclosure, Amount	$ 12,500
Unused Commitments to Extend Credit	6,519,034	$ 6,379,941
Valuation Allowance for Impairment of Recognized Servicing Assets, Sales and Disposals	1,400
Fair Value, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	4,700
Rabbi Trust [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	1,600
Alternative investments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other assets	25,000
Alternative investments [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unused Commitments to Extend Credit	$ 14,500

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Assets And Liabilities Measured On Recurring and Nonrecurring Basis) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	$ 3,304,217	$ 2,925,833
Gross derivative instruments, before netting (1)	343,890	133,158
Loans held for sale (valued under fair value option $29,018 and $35,750)	29,018	35,750
Financial liabilities held at fair value:
Derivative liability	772	7,163
Agency CMO [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	173,354	185,801
Agency MBS [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	1,527,270	1,612,164
Agency CMBS [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	1,051,754	581,552
Non-agency CMBS [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	455,025	431,871
CLO [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	84,361	92,205
Corporate debt securities [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	12,453	22,240
Fair Value, Recurring [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	3,304,217	2,925,833
Alternative investments (2)	8,238	4,331
Total financial assets held at fair value	3,734,569	3,116,731
Financial liabilities held at fair value:
Derivative liability	18,247	13,813
Fair Value, Recurring [Member] | Quoted Prices in Active Markets For Identical Assets (Level 1) [Member]
Financial assets held at fair value:
Alternative investments (2)	0	0
Total financial assets held at fair value	4,866	5,108
Financial liabilities held at fair value:
Derivative liability	229	611
Fair Value, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	3,304,217	2,925,833
Alternative investments (2)	0	0
Total financial assets held at fair value	3,721,465	3,107,292
Financial liabilities held at fair value:
Derivative liability	18,018	13,202
Fair Value, Recurring [Member] | Derivative instruments [Member]
Financial assets held at fair value:
Gross derivative instruments, before netting (1)	388,439	146,037
Fair Value, Recurring [Member] | Derivative instruments [Member] | Quoted Prices in Active Markets For Identical Assets (Level 1) [Member]
Financial assets held at fair value:
Gross derivative instruments, before netting (1)	209	328
Fair Value, Recurring [Member] | Derivative instruments [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Gross derivative instruments, before netting (1)	388,230	145,709
Fair Value, Recurring [Member] | Investments Held In Rabbi Trust [Member]
Financial assets held at fair value:
Other assets	4,657	4,780
Fair Value, Recurring [Member] | Investments Held In Rabbi Trust [Member] | Quoted Prices in Active Markets For Identical Assets (Level 1) [Member]
Financial assets held at fair value:
Other assets	4,657	4,780
Fair Value, Recurring [Member] | Loan Origination Commitments [Member]
Financial assets held at fair value:
Loans held for sale (valued under fair value option $29,018 and $35,750)	29,018	35,750
Fair Value, Recurring [Member] | Loan Origination Commitments [Member] | Quoted Prices in Active Markets For Identical Assets (Level 1) [Member]
Financial assets held at fair value:
Loans held for sale (valued under fair value option $29,018 and $35,750)	0	0
Fair Value, Recurring [Member] | Loan Origination Commitments [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Loans held for sale (valued under fair value option $29,018 and $35,750)	29,018	35,750
Fair Value, Recurring [Member] | Agency CMO [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	173,354	185,801
Fair Value, Recurring [Member] | Agency CMO [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	173,354	185,801
Fair Value, Recurring [Member] | Agency MBS [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	1,527,270	1,612,164
Fair Value, Recurring [Member] | Agency MBS [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	1,527,270	1,612,164
Fair Value, Recurring [Member] | Agency CMBS [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	1,051,754	581,552
Fair Value, Recurring [Member] | Agency CMBS [Member] | Quoted Prices in Active Markets For Identical Assets (Level 1) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	0	0
Fair Value, Recurring [Member] | Agency CMBS [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	1,051,754	581,552
Fair Value, Recurring [Member] | Agency CMBS [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	0	0
Fair Value, Recurring [Member] | Non-agency CMBS [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	455,025	431,871
Fair Value, Recurring [Member] | Non-agency CMBS [Member] | Quoted Prices in Active Markets For Identical Assets (Level 1) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	0	0
Fair Value, Recurring [Member] | Non-agency CMBS [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	455,025	431,871
Fair Value, Recurring [Member] | Non-agency CMBS [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	0	0
Fair Value, Recurring [Member] | CLO [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	84,361	92,205
Fair Value, Recurring [Member] | CLO [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	84,361	92,205
Fair Value, Recurring [Member] | Corporate debt securities [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	12,453	22,240
Fair Value, Recurring [Member] | Corporate debt securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets held at fair value:
Investment securities available-for-sale, at fair value	$ 12,453	$ 22,240

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Option, Disclosures (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for sale (valued under fair value option $29,018 and $35,750)	$ 29,018	$ 35,750
Loans held for sale (valued under fair value option $29,018 and $35,750)	29,018	36,053
Fair Value, Option, Loans Held as Assets, Aggregate Difference	585	564
loans held for sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for sale (valued under fair value option $29,018 and $35,750)	$ 28,433	$ 35,186

Fair Value Measurements (Summar

Fair Value Measurements (Summary Of Estimated Fair Values Of Significant Financial Instruments) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities held-to-maturity, net	$ 5,723,434		$ 5,293,918
Debt Securities, Held-to-maturity, Fair Value	6,006,416		5,380,653
Mortgage servicing assets, Carrying Amount	14,408	$ 14,926	17,484	$ 17,877	$ 18,712	$ 21,215
Fair Value, Nonrecurring [Member] | Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities held-to-maturity, net	5,723,128		5,293,918
Loans and leases, net	21,482,212		19,827,890
Securities sold under agreements to repurchase and other borrowings	1,301,822		1,040,431
FHLB advances	433,243		1,948,476
Long-term debt	568,846		540,364
Fair Value, Nonrecurring [Member] | Reported Value Measurement [Member] | Deposits Liabilities, other than time deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	24,350,113		20,219,981
Fair Value, Nonrecurring [Member] | Reported Value Measurement [Member] | Time Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	2,570,440		3,104,765
Fair Value, Nonrecurring [Member] | Reported Value Measurement [Member] | Residential
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing assets, Carrying Amount	14,408		17,484
Fair Value, Nonrecurring [Member] | Estimate of Fair Value Measurement [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities, Held-to-maturity, Fair Value	6,006,416		5,380,653
Securities sold under agreements to repurchase and other borrowings	1,305,029		1,041,042
FHLB advances	442,724		1,950,035
Long-term debt	525,170		555,775
Fair Value, Nonrecurring [Member] | Estimate of Fair Value Measurement [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans and leases, net	21,695,557		19,961,632
Fair Value, Nonrecurring [Member] | Estimate of Fair Value Measurement [Member] | Deposits Liabilities, other than time deposits [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	24,350,113		20,219,981
Fair Value, Nonrecurring [Member] | Estimate of Fair Value Measurement [Member] | Time Deposits [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Time deposits	2,580,279		3,102,316
Fair Value, Nonrecurring [Member] | Estimate of Fair Value Measurement [Member] | Residential | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Mortgage servicing assets, Fair value	$ 15,559		$ 33,250

Retirement Benefit Plans (Detai

Retirement Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Weighted-average expected long-term rate of return			5.75%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost on benefit obligations	$ 1,531	$ 2,001	$ 4,881	$ 5,956
Expected return on plan assets	(3,380)	(2,815)	(10,140)	(8,445)
Recognized net loss	1,036	1,420	3,021	4,280
Net periodic benefit cost	(813)	606	(2,238)	1,791
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost on benefit obligations	12	16	35	48
Expected return on plan assets	0	0	0	0
Recognized net loss	5	4	17	11
Net periodic benefit cost	17	20	52	59
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost on benefit obligations	9	22	34	64
Expected return on plan assets	0	0	0	0
Recognized net loss	(38)	(2)	(55)	(10)
Net periodic benefit cost	$ (29)	$ 20	$ (21)	$ 54

Segment Reporting (Operating Re

Segment Reporting (Operating Results and Total Assets Reportable Segments) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Assets	$ 32,994,443		$ 32,994,443		$ 30,389,344
Net interest income	219,256	$ 240,539	674,464	$ 723,877
Non-interest income	75,060	69,931	208,514	214,396
Non-interest expense	183,996	179,894	539,416	536,220
Pre-tax, pre-provision net revenue	110,320	130,576	343,562	402,053
Provision for credit losses	22,750	11,300	138,750	31,800
Income before income tax expense	87,570	119,276	204,812	370,253
Income tax expense	18,289	25,411	44,235	78,003
Net income	69,281	93,865	160,577	292,250
Operating Segments [Member] | Commercial Banking [Member]
Segment Reporting Information [Line Items]
Assets	12,666,764		12,666,764		11,541,803
Net interest income	107,417	104,549	311,595	303,107
Non-interest income	13,099	13,987	41,063	42,643
Non-interest expense	47,610	45,261	138,848	136,075
Pre-tax, pre-provision net revenue	72,906	73,275	213,810	209,675
Provision for credit losses	30,793	9,312	131,876	23,294
Income before income tax expense	42,113	63,963	81,934	186,381
Income tax expense	10,314	15,863	20,066	46,224
Net income	31,799	48,100	61,868	140,157
Operating Segments [Member] | HSA Bank [Member]
Segment Reporting Information [Line Items]
Assets	83,104		83,104		80,176
Net interest income	39,861	43,581	121,868	130,692
Non-interest income	27,235	23,526	76,721	74,082
Non-interest expense	34,789	32,918	105,887	100,693
Pre-tax, pre-provision net revenue	32,307	34,189	92,702	104,081
Provision for credit losses	0	0	0	0
Income before income tax expense	32,307	34,189	92,702	104,081
Income tax expense	8,626	9,060	24,751	27,582
Net income	23,681	25,129	67,951	76,499
Operating Segments [Member] | Community Banking [Member]
Segment Reporting Information [Line Items]
Assets	10,039,505		10,039,505		9,348,727
Net interest income	108,218	104,613	312,558	318,741
Non-interest income	28,970	28,115	79,995	81,172
Non-interest expense	98,991	99,835	291,644	291,076
Pre-tax, pre-provision net revenue	38,197	32,893	100,909	108,837
Provision for credit losses	(8,040)	1,988	6,965	8,506
Income before income tax expense	46,237	30,905	93,944	100,331
Income tax expense	9,155	6,552	18,601	21,269
Net income	37,082	24,353	75,343	79,062
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Assets	10,205,070		10,205,070		$ 9,418,638
Net interest income	(36,240)	(12,204)	(71,557)	(28,663)
Non-interest income	5,756	4,303	10,735	16,499
Non-interest expense	2,606	1,880	3,037	8,376
Pre-tax, pre-provision net revenue	(33,090)	(9,781)	(63,859)	(20,540)
Provision for credit losses	(3)	0	(91)	0
Income before income tax expense	(33,087)	(9,781)	(63,768)	(20,540)
Income tax expense	(9,806)	(6,064)	(19,183)	(17,072)
Net income	$ (23,281)	$ (3,717)	$ (44,585)	$ (3,468)

Segment Reporting Segment Repor

Segment Reporting Segment Reporting Narrative (Details)	9 Months Ended
	Sep. 30, 2020Segment
Segment Reporting Information [Line Items]
Number of Reportable Segments	3

Revenue from Contracts with C_3

Revenue from Contracts with Customers Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 51,627	$ 51,818	$ 149,837	$ 157,449
Non-interest income	75,060	69,931	208,514	214,396
Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	39,278	41,410	117,687	127,552
Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	8,255	8,496	24,096	24,456
Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	4,094	1,912	8,054	5,441
Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	23,433
Non-interest income		18,113	58,677	56,947
Operating Segments [Member] | Commercial Banking [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	5,552	5,637	16,429	16,784
Non-interest income	13,099	13,987	41,063	42,643
Operating Segments [Member] | Commercial Banking [Member] | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,883	2,987	8,645	9,108
Operating Segments [Member] | Commercial Banking [Member] | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,669	2,650	7,784	7,676
Operating Segments [Member] | Commercial Banking [Member] | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Operating Segments [Member] | Commercial Banking [Member] | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	7,547
Non-interest income		8,350	24,634	25,859
Operating Segments [Member] | HSA Bank [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	27,235	23,526	76,721	74,082
Non-interest income	27,235	23,526	76,721	74,082
Operating Segments [Member] | HSA Bank [Member] | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	23,667	22,264	70,250	70,496
Operating Segments [Member] | HSA Bank [Member] | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Operating Segments [Member] | HSA Bank [Member] | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	3,568	1,262	6,471	3,586
Operating Segments [Member] | HSA Bank [Member] | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0
Non-interest income		0	0	0
Operating Segments [Member] | Community Banking [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	18,795	22,552	56,703	66,362
Non-interest income	28,970	28,115	79,995	81,172
Operating Segments [Member] | Community Banking [Member] | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	12,704	16,047	38,784	47,701
Operating Segments [Member] | Community Banking [Member] | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	5,565	5,855	16,336	16,806
Operating Segments [Member] | Community Banking [Member] | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	526	650	1,583	1,855
Operating Segments [Member] | Community Banking [Member] | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	10,175
Non-interest income		5,563	23,292	14,810
Corporate, Non-Segment [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	45	103	(16)	221
Non-interest income	5,756	4,303	10,735	16,499
Corporate, Non-Segment [Member] | Deposit service fees [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	24	112	8	247
Corporate, Non-Segment [Member] | Wealth and investment services [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	21	(9)	(24)	(26)
Corporate, Non-Segment [Member] | Other non interest income [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Corporate, Non-Segment [Member] | Non-interest income within the scope of other GAAP topics [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 5,711
Non-interest income		$ 4,200	$ 10,751	$ 16,278

Commitments and Contingencies_2

Commitments and Contingencies (Outstanding Financial Instruments Contract Amounts Represent Credit Risk) (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	$ 6,519,034	$ 6,379,941
Standby letter of credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	204,981	188,103
Commercial letter of credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	26,270	29,180
Commitments to extend credit [Member]
Loss Contingencies [Line Items]
Unused Commitments to Extend Credit	$ 6,287,783	$ 6,162,658

(Reserve for Unfunded Commitmen

(Reserve for Unfunded Commitments) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Accounting Standards Update 2016-13 [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 0	$ 0	$ 9,139	$ 0
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	10,739	2,537	2,367	2,506
Provision (benefit) charged to non-interest expense	1,146	(68)	379	(37)
Ending balance	$ 11,885	$ 2,469	$ 11,885	$ 2,469