People's United Financial (PBCT) 10-Q 11 May 20 2020 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2020	Apr. 30, 2020
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-33326
Entity Registrant Name	PEOPLE’S UNITED FINANCIAL, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8447891
Entity Address, Address Line One	850 Main Street
Entity Address, City or Town	Bridgeport
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06604
City Area Code	(203)
Local Phone Number	338-7171
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		424,657,609
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001378946
Current Fiscal Year End Date	--12-31
Common Stock, $0.01 par value per share
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value per share
Trading Symbol	PBCT
Security Exchange Name	NASDAQ
Fixed-to-Floating Rate Non-Cumulative Perpetual Preferred Stock, Series A, $0.01 par value per share
Entity Information [Line Items]
Title of 12(b) Security	Fixed-to-Floating Rate Non-Cumulative Perpetual Preferred Stock, Series A, $0.01 par value per share
Trading Symbol	PBCTP
Security Exchange Name	NASDAQ

Consolidated Statements of Cond

Consolidated Statements of Condition - (Unaudited) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Assets
Cash and due from banks	$ 507.6	$ 484.2
Short-term investments	744.3	316.8
Total cash and cash equivalents (note 2)	1,251.9	801
Securities (note 2):
Trading debt securities, at fair value	0	7.1
Equity securities, at fair value	6.2	8.2
Debt securities available-for-sale, at fair value	4,276.6	3,564.3
Debt securities held-to-maturity, at amortized cost and net of allowance for credit losses of $1.9 million at March 31, 2020 (fair value of $4.07 billion and $4.02 billion)	3,861.5	3,869.2
Federal Home Loan Bank and Federal Reserve Bank stock, at cost	407.2	341.1
Total securities	8,551.5	7,789.9
Loans held-for-sale (note 3)	19.2	511.3
Loans (notes 3, 4 and 5):
Loans	44,284	43,596.1
Less allowance for credit losses	(341.7)	(246.6)
Total loans, net	43,942.3	43,349.5
Goodwill (note 8)	3,065.5	3,065.5
Bank-owned life insurance	707.6	705
Premises and equipment, net	300.8	305.5
Other acquisition-related intangible assets (note 8)	198.5	209.1
Other assets (notes 1, 3, 5 and 13)	2,396	1,853
Total assets	60,433.3	58,589.8
Deposits:
Non-interest-bearing	10,526	9,803.7
Savings	5,136	4,987.7
Interest-bearing checking and money market	20,238.9	19,592.6
Time	8,840.2	9,205.5
Total deposits	44,741.1	43,589.5
Borrowings:
Federal Home Loan Bank advances	4,489.7	3,125.4
Federal funds purchased	1,120	1,620
Customer repurchase agreements	301.1	409.1
Total borrowings	5,910.8	5,154.5
Notes and debentures	1,012.6	993.1
Other liabilities (notes 1, 4, 5 and 13)	1,043.3	905.5
Total liabilities	52,707.8	50,642.6
Commitments and contingencies (notes 1, 5 and 10)
Stockholders’ Equity (notes 6, 9 and 15)
Preferred stock ($0.01 par value; 50.0 million shares authorized; 10.0 million shares issued and outstanding at both dates)	244.1	244.1
Common stock ($0.01 par value; 1.95 billion shares authorized; 533.5 million shares and 532.8 million shares issued)	5.3	5.3
Additional paid-in capital	7,644.4	7,639.4
Retained earnings	1,514.5	1,512.8
Unallocated common stock of Employee Stock Ownership Plan, at cost (5.8 million shares and 5.9 million shares)	(121.1)	(122.9)
Accumulated other comprehensive loss	(92.7)	(166.9)
Treasury stock, at cost (109.0 million shares and 89.2 million shares)	(1,469)	(1,164.6)
Total stockholders’ equity	7,725.5	7,947.2
Total liabilities and stockholders’ equity	60,433.3	58,589.8
Commercial
Loans (notes 3, 4 and 5):
Loans	31,710	30,714.3
Less allowance for credit losses	(211.8)	(217.9)
Retail
Loans (notes 3, 4 and 5):
Loans	12,574	12,881.8
Less allowance for credit losses	(129.9)	(28.7)
Commercial real estate | Commercial
Loans (notes 3, 4 and 5):
Loans	14,651.6	14,762.3
Commercial and industrial | Commercial
Loans (notes 3, 4 and 5):
Loans	12,045.7	11,041.6
Equipment financing | Commercial
Loans (notes 3, 4 and 5):
Loans	5,012.7	4,910.4
Residential mortgage | Retail
Loans (notes 3, 4 and 5):
Loans	10,081.9	10,318.1
Home equity and other consumer | Retail
Loans (notes 3, 4 and 5):
Loans	$ 2,492.1	$ 2,563.7

Consolidated Statements of Co_2

Consolidated Statements of Condition - (Unaudited) (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Debt securities, allowance for credit loss	$ 1.9
Securities held to maturity, at fair value	$ 4,065.2	$ 4,020
Preferred stock, par value (USD per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock, shares issued (in shares)	10,000,000	10,000,000
Preferred stock, shares outstanding (in shares)	10,000,000	10,000,000
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,950,000,000	1,950,000,000
Common stock, shares issued (in shares)	533,500,000	532,800,000
Unallocated common stock of Employee Stock Ownership Plan (in shares)	5,836,579	5,900,000
Treasury stock (in shares)	109,000,000	89,200,000

Consolidated Statements of Inco

Consolidated Statements of Income - (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Interest and dividend income:
Commercial real estate	$ 149.6	$ 132.7
Commercial and industrial	106.4	103.9
Equipment financing	68.2	59
Residential mortgage	90.4	70.7
Home equity and other consumer	28	24.9
Total interest on loans	442.6	391.2
Securities	51.2	47.8
Loans held-for-sale	3.3	0.2
Short-term investments	2	1.3
Total interest and dividend income	499.1	440.5
Interest expense:
Deposits	78.9	81.2
Borrowings	15.4	17.7
Notes and debentures	8.8	8.8
Total interest expense	103.1	107.7
Net interest income	396	332.8
Provision for credit losses (notes 3 and 4)	33.5	5.6
Net interest income after provision for credit losses	362.5	327.2
Non-interest income:
Operating leases	12.6	12.7
Commercial banking lending fees	12.1	7.8
Insurance revenue	10.9	10.5
Cash management fees	7.4	6.8
Other non-interest income (note 2)	34.7	12.3
Total non-interest income	123.8	94.6
Non-interest expense:
Compensation and benefits	173.9	155.4
Occupancy and equipment	51	44.3
Professional and outside services	38.5	20
Amortization of other acquisition-related intangible assets (note 8)	10.7	6.7
Operating lease expense	9.8	9.4
Regulatory assessments	8.7	7
Other non-interest expense	27.5	34.4
Total non-interest expense	320.1	277.2
Income before income tax expense	166.2	144.6
Income tax expense (note 1)	35.8	30
Net income	130.4	114.6
Preferred stock dividend	3.5	3.5
Net income available to common shareholders	$ 126.9	$ 111.1
Earnings per common share (note 7):
Basic (USD per share)	$ 0.30	$ 0.30
Diluted (USD per share)	$ 0.30	$ 0.30
Bank service charges
Non-interest income:
Fees	$ 28	$ 25.2
Investment management fees
Non-interest income:
Fees	$ 18.1	$ 19.3

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 130.4	$ 114.6
Other comprehensive income, net of tax:
Net actuarial gains and losses related to pension and other postretirement plans	1.6	1.8
Net unrealized gains and losses on debt securities available-for-sale	71.6	29
Amortization of unrealized losses on debt securities transferred to held-to-maturity	1	0.6
Net unrealized gains and losses on derivatives accounted for as cash flow hedges	0	0.8
Total other comprehensive income, net of tax (note 6)	74.2	32.2
Total comprehensive income	$ 204.6	$ 146.8

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - (Unaudited) - USD ($) $ in Millions	Total	Preferred Stock	Common Stock, $0.01 par value per share	Additional Paid-In Capital	Retained Earnings	Unallocated ESOP Common Stock	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning Balance at Dec. 31, 2018	$ 6,533.9	$ 244.1	$ 4.7	$ 6,549.3	$ 1,284.8	$ (130.1)	$ (256.8)	$ (1,162.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	114.6				114.6
Total other comprehensive income (loss), net of tax (note 6)	32.2						32.2
Cash dividends on common stock	(65.2)				(65.2)
Cash dividend on preferred stock	(3.5)				(3.5)
Restricted stock and performance-based share awards	1			1
ESOP common stock committed to be released (note 9)	1.4				(0.4)	1.8
Common stock repurchased and retired upon vesting of restricted stock awards	(1.7)				(1.7)
Stock options exercised	8.5			8.5
Ending Balance at Mar. 31, 2019	6,621.2	244.1	4.7	6,558.8	1,328.6	(128.3)	(224.6)	(1,162.1)
Beginning Balance at Dec. 31, 2019	7,947.2	244.1	5.3	7,639.4	1,512.8	(122.9)	(166.9)	(1,164.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	130.4				130.4
Total other comprehensive income (loss), net of tax (note 6)	74.2						74.2
Cash dividends on common stock	(77.3)				(77.3)
Cash dividend on preferred stock	(3.5)				(3.5)
Restricted stock and performance-based share awards	2.4			2.4
Common stock repurchased (note 6)	(304.4)							(304.4)
ESOP common stock committed to be released (note 9)	1.2				(0.6)	1.8
Common stock repurchased and retired upon vesting of restricted stock awards	(1.4)				(1.4)
Stock options exercised	2.6			2.6
Ending Balance at Mar. 31, 2020	$ 7,725.5	$ 244.1	$ 5.3	$ 7,644.4	$ 1,514.5	$ (121.1)	$ (92.7)	$ (1,469)

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Stockholders' Equity - (Unaudited) (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Retained Earnings
Cash dividends on common stock (USD per share)	$ 0.1775	$ 0.1750

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash Flows from Operating Activities:
Net income	$ 130.4	$ 114.6
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for credit losses	33.5	5.6
Depreciation and amortization of premises and equipment	11.2	9.5
Amortization of other acquisition-related intangible assets	10.7	6.7
Expense related to operating leases	9.8	9.4
Expense related to share-based awards	7.1	6.2
ESOP common stock committed to be released	1.2	1.4
Net gains on sales of loans	(15.5)	(0.4)
Net losses on sales of residential mortgage loans	(0.7)	(0.2)
Originations of loans held-for-sale	(48.7)	(23.5)
Proceeds from sales of loans held-for-sale	540.6	35.4
Net decrease in trading debt securities	7.1	0.1
Excess income tax benefits from stock option exercises	0	0.3
Net changes in other assets and other liabilities	(470.9)	(186.6)
Net cash provided by (used in) operating activities	215.8	(21.5)
Cash Flows from Investing Activities:
Proceeds from sales of equity securities	0.7	0.2
Proceeds from principal repayments and maturities of debt securities available-for-sale	207.9	105.8
Proceeds from sales of debt securities available-for-sale	0.1	170.4
Proceeds from principal repayments and maturities of debt securities held-to-maturity	94.8	33
Purchases of debt securities available-for-sale	(822.8)	(184.4)
Purchases of debt securities held-to-maturity	(87.3)	(59.1)
Net purchases of Federal Reserve Bank stock	(24)	(15)
Net (purchases) redemptions of Federal Home Loan Bank stock	(42.2)	42.8
Proceeds from sales of loans	27.8	14.8
Net principal disbursements of loans	(624.9)	(274.7)
Purchases of loans	(8.5)	(15.8)
Purchases of premises and equipment	(7.8)	(1.9)
Purchases of leased equipment, net	(3.8)	(2.4)
Proceeds from sales of real estate owned	3.3	5.6
Return of premium on bank-owned life insurance, net	0	0.5
Net cash paid in acquisitions	0	(60)
Net cash used in investing activities	(1,286.7)	(240.2)
Cash Flows from Financing Activities:
Net increase in deposits	1,151.6	741.9
Net increase (decrease) in borrowings with terms of three months or less	766.2	(702.5)
Repayments of borrowings with terms of more than three months	(10.1)	(31.7)
Cash dividends paid on common stock	(77.3)	(65.2)
Cash dividends paid on preferred stock	(3.5)	(3.5)
Repurchases of common stock	(305.8)	(1.7)
Proceeds from stock options exercised	0.7	6.9
Net cash provided by (used in) financing activities	1,521.8	(55.8)
Net increase (decrease) in cash and cash equivalents	450.9	(317.5)
Cash and cash equivalents at beginning of period	801	932
Cash and cash equivalents at end of period	1,251.9	614.5
Supplemental Information:
Interest payments	105.4	107
Income taxes payments	13.2	9.1
Significant non-cash transactions:
Right-of-use assets obtained in exchange for lessee operating lease liabilities	14.3	10.3
Unsettled purchases of securities	7.5	14.6
Real estate properties acquired by foreclosure	$ 1.6	$ 2.9

General

General	3 Months Ended
	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	NOTE 1. GENERAL In the opinion of management, the accompanying unaudited consolidated financial statements of People’s United Financial, Inc. (“People’s United” or the “Company”) have been prepared to reflect all adjustments necessary to present fairly the financial position and results of operations as of the dates and for the periods shown. All significant intercompany transactions and balances are eliminated in consolidation. Certain reclassifications have been made to prior period amounts to conform to the current period presentation. In preparing the consolidated financial statements, management is required to make significant estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses. Actual results could differ from management’s current estimates, as a result of changing conditions and future events. Several accounting estimates are particularly critical and are susceptible to significant near-term change, including the allowance for credit losses ("ACL") and asset impairment judgments, such as the recoverability of goodwill and other intangible assets. These accounting estimates are reviewed with the Audit Committee of the Board of Directors. The Financial Accounting Standards Board (the "FASB") has issued changes to several accounting standards, some of which govern key aspects of the Company’s financial statements. Most notably, the FASB’s standard on accounting for credit losses (the “CECL standard”), removes from U.S. generally accepted accounting principles (“GAAP”) the existing “probable” threshold for recognizing credit losses and, instead, utilizes an “expected credit loss” measurement principle. The CECL standard, which was adopted by the Company on January 1, 2020, is applied in the recognition of credit losses for loans and held-to-maturity securities and other receivables at the time the financial asset is originated or acquired and adjusted each period for changes in expected credit losses. This standard represents a significant change in GAAP and may result in material changes to the Company’s Consolidated Financial Statements. See Note 2, "Securities", Note 3, "Loans", Note 4, "Allowance for Credit Losses" and Note 15, "New Accounting Pronouncements" for more information. The judgments used by management in applying critical accounting policies may be affected by economic conditions, which may result in changes to future financial results. For example, subsequent evaluations of the loan portfolio, in light of the factors then prevailing, may result in significant changes in the ACL in future periods, and the inability to collect outstanding principal may result in increased credit losses. Certain information and footnote disclosures normally included in consolidated financial statements prepared in conformity with U.S. GAAP have been omitted or condensed. As a result, the accompanying consolidated financial statements should be read in conjunction with People’s United’s Annual Report on Form 10-K for the year ended December 31, 2019. The results of operations for the three months ended March 31, 2020 are not necessarily indicative of the results of operations that may be expected for the entire year or any other interim period. Note 1 to People’s United’s audited consolidated financial statements included in the Annual Report on Form 10-K for the year ended December 31, 2019, as supplemented by this Quarterly Report for the period ended March 31, 2020 provides disclosure of People’s United’s significant accounting policies. People’s United holds ownership interests in limited partnerships formed to develop and operate affordable housing units for lower income tenants throughout its franchise area. The underlying partnerships, which are considered variable interest entities, are not consolidated into the Company’s Consolidated Financial Statements. These investments have historically played a role in enabling People’s United Bank, National Association (the “Bank”) to meet its Community Reinvestment Act requirements while, at the same time, providing federal income tax credits. Affordable housing investments, including all legally binding commitments to fund future investments, are included in other assets in the Consolidated Statements of Condition ($426.1 million and $383.9 million at March 31, 2020 and December 31, 2019, respectively). Included in other liabilities in the Consolidated Statements of Condition is a liability for all legally binding unfunded commitments to fund future investments ($164.1 million and $141.1 million at those dates). The cost of the Company’s investments is amortized on a straight-line basis over the period during which the related federal income tax credits are realized (generally 10 years). Amortization expense, which is included as a component of income tax expense, totaled $7.0 million and $5.4 million for the three months ended March 31, 2020 and 2019, respectively. On March 11, 2020, the World Health Organization declared the outbreak of a strain of novel coronavirus disease (“COVID-19”) a global pandemic. Economic activity in many countries, including the United States, began to deteriorate rapidly as the COVID-19 pandemic spread across the globe. In the United States, which has been operating under a presidentially-declared national emergency since March 13, 2020, the COVID-19 pandemic has caused severe disruption to the capital markets as well as business and economic activity. Throughout the month of March, individual municipalities and entire states adopted travel and work location restrictions, social distancing requirements, and in some cases, shelter-in-place protocols in order to slow the spread of the virus. These measures resulted in the closure of many schools, stores, offices, restaurants and manufacturing facilities, causing a decline in spending and an increase in layoffs. As a result, negative trends in both U.S. Gross Domestic Product ("GDP") and unemployment are expected to persist throughout 2020. In response, the Federal government introduced several measures to mitigate the magnitude of the pandemic’s effects. Most notably, on March 27, 2020, the Coronavirus Aid, Relief and Economic Security Act (the "CARES Act"), which provides financial assistance for businesses and individuals as well as targeted regulatory relief for financial institutions, was signed into law. The impact of the COVID-19 pandemic on economic conditions, both in the United States and abroad, has created global uncertainty about the future economic environment including the length and depth of any global recession that may occur. Concerns over interest rates, domestic and global policy issues, U.S. trade policy and geopolitical events, and the influence of those factors on the markets in general, further add to this uncertainty.

Cash and Cash Equivalents and S

Cash and Cash Equivalents and Securities	3 Months Ended
	Mar. 31, 2020
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents and Securities	NOTE 2. CASH AND CASH EQUIVALENTS AND SECURITIES Included in short-term investments are interest-bearing deposits at the Federal Reserve Bank of New York (the “FRB-NY”) totaling $525.6 million at March 31, 2020 and $219.4 million at December 31, 2019. These deposits represent an alternative to overnight federal funds sold and yielded 0.10% and 1.55% at March 31, 2020 and December 31, 2019, respectively. In connection with the Company’s adoption of the CECL standard, selected accounting policies related to securities have been revised and/or certain accounting policy elections have been implemented. These policies are described below. Allowance for Credit Losses – Available-for-Sale Securities For available-for sale securities in an unrealized loss position, management first assesses whether (i) the Company intends to sell, or (ii) it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either criteria are met, any previously recognized allowances are charged-off and the security's amortized cost is written down to fair value through income. If neither criteria are met, the security is evaluated to determine whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and any adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, an ACL is recorded for the credit loss, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that has not been recorded through an ACL is recognized in other comprehensive income. Adjustments to the allowance are reported as a component of credit loss expense. Available-for-sale securities are charged-off against the allowance or, in the absence of any allowance, written down through income when deemed uncollectible or when either of the aforementioned criteria regarding intent or requirement to sell is met. The Company has made the accounting policy election to exclude accrued interest receivable on available-for-sale securities from the estimate of credit losses. Accrued interest receivable associated with debt securities available-for-sale totaling $11.4 million at March 31, 2020 is reported in other assets in the Consolidated Statements of Condition. Allowance for Credit Losses – Held-to-Maturity Securities Management measures expected credit losses on held-to-maturity securities on a collective basis by major security type with each type sharing similar risk characteristics, and considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Held-to-maturity securities are charged-off against the allowance when deemed to be uncollectible and adjustments to the allowance are reported as a component of credit loss expense. The Company has made the accounting policy election to exclude accrued interest receivable on held-to-maturity securities from the estimate of credit losses. Accrued interest receivable associated with debt securities held-to-maturity totaling $32.0 million at March 31, 2020 is reported in other assets in the Consolidated Statements of Condition. With regard to U.S. Treasury and residential mortgage-backed securities issued by the U.S. government, or agencies thereof, it is expected that the securities will not be settled at prices less than the amortized cost bases of the securities as such securities are backed by the full faith and credit of and/or guaranteed by the U.S. government. Accordingly, no ACL has been recorded for these securities. With regard to securities issued by corporations, states and/or political subdivisions and other held-to-maturity securities, management considers a number of factors, including: (i) issuer bond ratings; (ii) historical loss rates for given bond ratings; and (iii) whether issuers continue to make timely principal and interest payments under the contractual terms of the securities. The amortized cost, ACL, gross unrealized gains and losses, and fair value of People’s United’s debt securities available-for-sale and debt securities held-to-maturity are as follows: As of March 31, 2020 (in millions) Amortized ACL (1) Gross Gross Fair Debt securities available-for-sale: U.S. Treasury and agency $ 731.3 $ — $ 15.9 $ — $ 747.2 GSE (2) mortgage-backed and 3,425.1 — 104.4 (0.1) 3,529.4 Total debt securities $ 4,156.4 $ — $ 120.3 $ (0.1) $ 4,276.6 Debt securities held-to-maturity: State and municipal $ 2,574.9 $ 0.1 $ 151.4 $ (1.5) $ 2,724.9 GSE mortgage-backed securities 1,190.8 — 49.7 — 1,240.5 Corporate 96.2 1.8 1.6 (1.3) 98.3 Other 1.5 — — — 1.5 Total debt securities $ 3,863.4 $ 1.9 $ 202.7 $ (2.8) $ 4,065.2 (1) As discussed in Note 15, beginning January 1, 2020, an ACL is required to be recognized (as appropriate) for debt securities. (2) Government sponsored enterprise (3) Collateralized mortgage obligation As of December 31, 2019 (in millions) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Debt securities available-for-sale: U.S. Treasury and agency $ 689.5 $ 0.4 $ (2.8) $ 687.1 GSE mortgage-backed and CMO securities 2,856.3 25.0 (4.1) 2,877.2 Total debt securities available-for-sale $ 3,545.8 $ 25.4 $ (6.9) $ 3,564.3 Debt securities held-to-maturity: State and municipal $ 2,503.9 $ 142.0 $ (0.4) $ 2,645.5 GSE mortgage-backed securities 1,271.4 8.0 (0.3) 1,279.1 Corporate 92.4 1.5 — 93.9 Other 1.5 — — 1.5 Total debt securities held-to-maturity $ 3,869.2 $ 151.5 $ (0.7) $ 4,020.0 Both at adoption of the CECL standard on January 1, 2020 and at March 31, 2020, the ACL on debt securities held-to-maturity totaled $1.8 million related to corporate bonds and $0.1 million related to state and municipal securities. At March 31, 2020, no debt securities held-to-maturity were past due or in non-accrual status. Credit Quality Indicators Credit ratings, which are updated monthly, are a key measure for estimating the probability of a bond's default and for monitoring credit quality on an on-going basis. For bonds other than U.S. Treasuries and bonds issued or guaranteed by U.S. government agencies, credit ratings issued by one or more nationally recognized statistical rating organizations such as Moody's, S&P, Fitch or Kroll are considered in conjunction with an assessment by the Company's risk management department. In the case of multiple ratings, generally the lower rating prevails. Investment grade reflects a credit rating of BBB- or above. The table below indicates the credit profile of the Company's debt securities held-to-maturity at amortized cost: As of March 31, 2020 (in millions) Investment Grade Non-Investment Grade Total State and municipal $ 2,574.5 $ 0.4 $ 2,574.9 GSE mortgage-backed securities 1,190.8 — 1,190.8 Corporate 91.2 5.0 96.2 Other 1.5 — 1.5 Total $ 3,858.0 $ 5.4 $ 3,863.4 The following table summarizes those debt securities available-for-sale with unrealized losses at March 31, 2020, classified as to the length of time the losses have existed and, for which no ACL has been recognized: Continuous Unrealized Loss Position Less Than 12 Months 12 Months Or Longer Total As of March 31, 2020 (in millions) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Debt securities available-for-sale: GSE mortgage-backed and CMO $ 10.9 $ (0.1) $ — $ — $ 10.9 $ (0.1) Total $ 10.9 $ (0.1) $ — $ — $ 10.9 $ (0.1) At March 31, 2020, two of the 272 available-for-sale debt securities owned by the Company had gross unrealized losses totaling less than $0.1 million. The GSE mortgage-backed and CMO securities with unrealized losses had AAA credit ratings and an average contractual maturity of 27 years. As of March 31, 2020, no ACL has been recognized on available-for-sale debt securities in an unrealized loss position as management does not believe any of the securities are impaired due to reasons of credit quality. Rather, the cause of the gross unrealized losses with respect to all of the debt securities is directly related to changes in interest rates. At this time, management does not intend to sell such securities nor is it more likely than not, based upon available evidence, that management will be required to sell such securities prior to recovery. No credit impairment losses were recognized in the Consolidated Statements of Income for the three months ended March 31, 2020 or 2019. The following table summarizes those debt securities with unrealized losses at December 31, 2019, classified as to the length of time the unrealized losses have existed. Certain unrealized losses totaled less than $0.1 million. Continuous Unrealized Loss Position Less Than 12 Months 12 Months Or Longer Total As of December 31, 2019 (in millions) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Debt securities available-for-sale: GSE mortgage-backed and CMO $ 565.4 $ (3.1) $ 509.3 $ (1.0) $ 1,074.7 $ (4.1) U.S. Treasury and agency 181.0 (0.4) 362.4 (2.4) 543.4 (2.8) Total debt securities available-for-sale $ 746.4 $ (3.5) $ 871.7 $ (3.4) $ 1,618.1 $ (6.9) Debt securities held-to-maturity: GSE mortgage-backed securities $ 100.9 $ (0.3) $ 9.1 $ — $ 110.0 $ (0.3) State and municipal 33.0 (0.2) 11.4 (0.2) 44.4 (0.4) Corporate 3.5 — 8.6 — 12.1 — Total debt securities held-to-maturity $ 137.4 $ (0.5) $ 29.1 $ (0.2) $ 166.5 $ (0.7) At March 31, 2020 and December 31, 2019, debt securities available-for-sale with fair values of $2.46 billion and $2.43 billion, respectively, and debt securities held-to-maturity with amortized costs of $1.62 billion and $1.47 billion, respectively, were pledged as collateral for public deposits and for other purposes. The following table is a summary of the amortized cost and fair value of debt securities as of March 31, 2020, based on remaining period to contractual maturity. Information for GSE mortgage-backed and CMO securities is based on the final contractual maturity dates without considering repayments and prepayments. Available-for-Sale Held-to-Maturity (in millions) Amortized Cost Fair Value Amortized Cost Fair Value U.S. Treasury and agency: Within 1 year $ 200.8 $ 201.4 $ — $ — After 1 but within 5 years 530.5 545.8 — — Total 731.3 747.2 — — GSE mortgage-backed and CMO securities: After 1 but within 5 years 83.2 87.3 841.2 879.3 After 5 but within 10 years 880.8 918.9 77.5 82.4 After 10 years 2,461.1 2,523.2 272.1 278.8 Total 3,425.1 3,529.4 1,190.8 1,240.5 State and municipal: Within 1 year — — 10.0 10.0 After 1 but within 5 years — — 245.5 254.3 After 5 but within 10 years — — 471.4 499.4 After 10 years — — 1,848.0 1,961.2 Total — — 2,574.9 2,724.9 Corporate: Within 1 year — — 5.0 5.0 After 1 but within 5 years — — 2.5 2.5 After 5 but within 10 years — — 88.7 90.8 Total — — 96.2 98.3 Other: Within 1 year — — 1.5 1.5 Total — — 1.5 1.5 Total: Within 1 year 200.8 201.4 16.5 16.5 After 1 but within 5 years 613.7 633.1 1089.2 1,136.1 After 5 but within 10 years 880.8 918.9 637.6 672.6 After 10 years 2,461.1 2,523.2 2,120.1 2,240.0 Total $ 4,156.4 $ 4,276.6 $ 3,863.4 $ 4,065.2 Security transactions are recorded on the trade date. Realized gains and losses are determined using the specific identification method and reported in non-interest income. Equity investments (other than equity method investments) are measured at fair value with changes in fair value recognized in net income. People’s United recorded unrealized losses of $1.4 million and unrealized gains of $0.2 million for the three months ended March 31, 2020 and 2019, respectively (included in other non-interest income in the Consolidated Statements of Income) relating to the change in fair value of its equity securities during the respective periods. The Bank, as a member of the Federal Home Loan Bank (the “FHLB”) of Boston, is currently required to purchase and hold shares of capital stock in the FHLB of Boston (total cost of $178.7 million and $136.6 million at March 31, 2020 and December 31, 2019, respectively) in an amount equal to its membership base investment plus an activity based investment determined according to the Bank’s level of outstanding FHLB advances. As a result of prior acquisitions, the Bank acquired shares of capital stock in the FHLB of New York (total cost of $0.7 million at both March 31, 2020 and December 31, 2019). Based on the current capital adequacy and liquidity position of both the FHLB of Boston and the FHLB of New York, management believes there is no impairment in the Company’s investment at March 31, 2020 and the cost of the investment approximates fair value. The Bank, as a member of the Federal Reserve Bank system, is currently required to purchase and hold shares of capital stock in the FRB-NY (total cost of $227.8 million and $203.8 million at March 31, 2020 and December 31, 2019, respectively) in an amount equal to 6% of its capital and surplus. Based on the current capital adequacy and liquidity position of the FRB-NY, management believes there is no impairment in the Company’s investment at March 31, 2020 and the cost of the investment approximates fair value.

Loans

Loans	3 Months Ended
	Mar. 31, 2020
Receivables [Abstract]
Loans	NOTE 3. LOANS As a result of adopting the CECL standard on January 1, 2020, the Company’s prior distinction between the originated loan portfolio and the acquired loan portfolio is no longer necessary. Accordingly, prior period disclosures have been revised to conform to the current period presentation. People’s United has identified two loan portfolio segments, Commercial and Retail, which are comprised of the following loan classes: • Commercial Portfolio : commercial real estate; commercial and industrial; equipment financing; and mortgage warehouse/asset based lending ("MWABL"). • Retail Portfolio : residential mortgage; home equity; and other consumer. These portfolio segments and loan classes are unchanged following the adoption of the CECL standard with the exception of MWABL which, prior to January 1, 2020, was included in commercial and industrial. The following table summarizes People’s United’s loans by loan portfolio segment and class: (in millions) March 31, 2020 December 31, 2019 Commercial: Commercial real estate $ 14,651.6 $ 14,762.3 Commercial and industrial 9,097.7 8,693.2 Equipment financing 5,012.7 4,910.4 MWABL 2,948.0 2,348.4 Total Commercial Portfolio 31,710.0 30,714.3 Retail: Residential mortgage: Adjustable-rate 6,825.2 7,064.8 Fixed-rate 3,256.7 3,253.3 Total residential mortgage 10,081.9 10,318.1 Home equity and other consumer: Home equity 2,349.9 2,406.5 Other consumer 142.2 157.2 Total home equity and other consumer 2,492.1 2,563.7 Total Retail Portfolio 12,574.0 12,881.8 Total loans $ 44,284.0 $ 43,596.1 In connection with the Company’s adoption of the CECL standard, selected accounting policies related to loans have been revised and/or certain accounting policy elections have been implemented. These policies are described below. Basis of Accounting Loans are reported at amortized cost less the ACL. Interest on loans is accrued to income monthly based on outstanding principal balances. Loan origination fees and certain direct loan origination costs are deferred, and the net fee or cost is recognized in interest income as an adjustment of yield. Depending on the loan portfolio, amounts are amortized or accreted using the level yield method over either the actual life or the estimated average life of the loan. Net deferred loan costs, which are included in loans by respective class, totaled $73.5 million at March 31, 2020 and $87.5 million at December 31, 2019. Allowance for Credit Losses The ACL on loans, calculated in accordance with the CECL standard, is deducted from the amortized cost basis of loans to present the net amount expected to be collected. The amount of the allowance represents management's best estimate of current expected credit losses on loans considering available information, from both internal and external sources, deemed relevant to assessing collectability over the loans' contractual terms, adjusted for expected prepayments when appropriate. Accrued interest on loans is excluded from the calculation of the ACL due to the Bank’s established non-accrual policy which results in the reversal of uncollectible accrued interest on non-accrual loans against interest income in a timely manner (see below). Accrued interest receivable associated with loans totaling $111.9 million at March 31, 2020 is reported in other assets in the Consolidated Statements of Condition. See Note 4, “Allowance for Credit Losses”. Purchased Credit Deteriorated (“PCD”) Loans In addition to originating loans, the Company may acquire loans through portfolio purchases or acquisitions of other companies. Purchased loans that have evidence of more than insignificant credit deterioration since origination are deemed PCD loans. In connection with its adoption of the CECL standard, the Company did not reassess whether previously recognized purchased credit impaired (“PCI”) loans accounted for under prior accounting guidance met the criteria of a PCD loan as of the date of adoption. PCD loans are initially recorded at fair value along with an ACL determined using the same methodology as originated loans. The sum of the loan's purchase price and ACL becomes its initial amortized cost basis. The difference between the initial amortized cost basis and the par value of the loan is a noncredit discount or premium, which is amortized into interest income over the life of the loan. Subsequent changes to the ACL are recorded through provision for credit losses. Past Due and Non-Accrual Loans Loans are considered past due if required principal and interest payments have not been received as of the date such payments were contractually due. A loan is generally considered “non-performing” when it is placed on non-accrual status. A loan is generally placed on non-accrual status when it becomes 90 days past due as to interest or principal payments. A loan may be placed on non-accrual status before it reaches 90 days past due if such loan has been identified as presenting uncertainty with respect to the collectability of interest and principal. A loan past due 90 days or more may remain on accruing status if such loan is both well secured and in the process of collection. All previously accrued but unpaid interest on non-accrual loans is reversed from interest income in the period in which the accrual of interest is discontinued. Interest payments received on non-accrual loans are generally applied as a reduction of principal if future collections are doubtful, although such interest payments may be recognized as income. Interest income recognized on non-accrual loans for the three months ended March 31, 2020 totaled less than $0.5 million. A loan remains on non-accrual status until the factors that indicated doubtful collectability no longer exist or until a loan is determined to be uncollectible and is charged-off against the ACL. There were no loans past due 90 days or more and still accruing interest at March 31, 2020 or December 31, 2019. The following tables summarize aging information by class of loan: Past Due As of March 31, 2020 (in millions) Current 30-89 Days 90 Days or More Total Total Commercial: Commercial real estate $ 14,580.0 $ 43.7 $ 27.9 $ 71.6 $ 14,651.6 Commercial and industrial 9,055.4 18.8 23.5 42.3 9,097.7 Equipment financing 4,853.2 136.4 23.1 159.5 5,012.7 MWABL 2,948.0 — — — 2,948.0 Total 31,436.6 198.9 74.5 273.4 31,710.0 Retail: Residential mortgage 9,978.3 64.2 39.4 103.6 10,081.9 Home equity 2,325.3 13.3 11.3 24.6 2,349.9 Other consumer 141.2 0.9 0.1 1.0 142.2 Total 12,444.8 78.4 50.8 129.2 12,574.0 Total loans $ 43,881.4 $ 277.3 $ 125.3 $ 402.6 $ 44,284.0 Included in the “Current” and “30-89 Days” categories above are early non-performing commercial real estate loans, commercial and industrial loans, equipment financing loans and MWABL loans totaling $24.2 million, $33.6 million, $19.4 million and $1.1 million, respectively, and $38.0 million of retail loans in the process of foreclosure or bankruptcy. These loans are less than 90 days past due but have been placed on non-accrual status as a result of having been identified as presenting uncertainty with respect to the collectability of interest and principal. Past Due As of December 31, 2019 (in millions) Current 30-89 Days 90 Days or More Total Total Commercial: Commercial real estate $ 14,713.8 $ 22.3 $ 26.2 $ 48.5 $ 14,762.3 Commercial and industrial 11,010.7 13.1 17.8 30.9 11,041.6 Equipment financing 4,791.0 97.9 21.5 119.4 4,910.4 Total 30,515.5 133.3 65.5 198.8 30,714.3 Retail: Residential mortgage 10,215.9 65.5 36.7 102.2 10,318.1 Home equity 2,385.7 9.9 10.9 20.8 2,406.5 Other consumer 156.1 1.1 — 1.1 157.2 Total 12,757.7 76.5 47.6 124.1 12,881.8 Total loans $ 43,273.2 $ 209.8 $ 113.1 $ 322.9 $ 43,596.1 Included in the “Current” and “30-89 Days” categories above are early non-performing commercial real estate loans, commercial and industrial loans, and equipment financing loans totaling $27.6 million, $23.0 million and $26.2 million, respectively, and $36.8 million of retail loans in the process of foreclosure or bankruptcy. These loans are less than 90 days past due but have been placed on non-accrual status as a result of having been identified as presenting uncertainty with respect to the collectability of interest and principal. The recorded investment in non-accrual loans, by class of loan and year of origination, is summarized as follows: March 31, 2020 Dec. 31, 2019 Non-Accrual Loans (in millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Non-Accrual Loans With No ACL Non-Accrual Loans Commercial: Commercial real estate $ — $ 16.3 $ 2.1 $ 2.1 $ 4.9 $ 28.0 $ 0.1 $ 53.5 $ 5.3 $ 53.8 Commercial and industrial 0.3 2.9 0.6 2.2 2.1 14.7 31.7 54.5 7.2 38.5 Equipment financing 0.9 10.6 13.4 8.6 4.3 4.7 — 42.5 1.9 47.7 MWABL — — — — — — 1.1 1.1 — — Total (1) 1.2 29.8 16.1 12.9 11.3 47.4 32.9 151.6 14.4 140.0 Retail: Residential mortgage — 1.3 3.2 2.3 1.4 58.4 — 66.6 22.0 63.3 Home equity — — 0.1 — 0.2 3.7 18.1 22.1 5.6 20.8 Other consumer — — 0.1 — — — — 0.1 — — Total (2) — 1.3 3.4 2.3 1.6 62.1 18.1 88.8 27.6 84.1 Total $ 1.2 $ 31.1 $ 19.5 $ 15.2 $ 12.9 $ 109.5 $ 51.0 $ 240.4 $ 42.0 $ 224.1 (1) Reported net of government guarantees totaling $1.2 million and $1.3 million at March 31, 2020 and December 31, 2019, respectively. These government guarantees relate, almost entirely, to guarantees provided by the Small Business Administration as well as selected other Federal agencies and represent the carrying value of the loans that are covered by such guarantees, the extent of which (i.e. full or partial) varies by loan. At March 31, 2020, all of the government guarantees related to commercial and industrial loans. (2) Includes $25.4 million and $17.0 million of loans in the process of foreclosure at March 31, 2020 and December 31, 2019, respectively. Collateral Dependent Loans Loans for which the borrower is experiencing financial difficulty and repayment is expected to be provided substantially through the operation or sale of the collateral are considered to be collateral dependent loans. Collateral can have a significant financial effect in mitigating exposure to credit risk and, where there is sufficient collateral, an allowance for expected credit losses is not recognized or is minimal. For collateral dependent commercial loans, the allowance for expected credit losses is individually assessed based on the fair value of the collateral. Various types of collateral are used, including real estate, inventory, equipment, accounts receivable, securities and cash, among others. For commercial real estate loans, collateral values are generally based on appraisals which are updated based on management judgment under the specific circumstances on a case-by-case basis. The collateral value for other financial assets is generally based on quoted market prices or broker quotes (in the case of securities) or appraisals. Commercial loan balances are charged-off at the time all or a portion of the balance is deemed uncollectible. At March 31, 2020, the Company had collateral dependent commercial loans totaling $28.1 million. Collateral dependent residential mortgage and home equity loans are carried at the lower of amortized cost or fair value of the collateral less costs to sell, with any excess in the carrying amount of the loan representing the related ACL. Collateral values are based on broker price opinions or appraisals. At March 31, 2020, the Company had collateral dependent residential mortgage and home equity loans totaling $29.2 million. Troubled Debt Restructurings (“TDRs”) TDRs, which, beginning in 2020, also includes loans reasonably expected to become TDRs, represent loans for which the original contractual terms have been modified to provide for terms that are less than what the Company would be willing to accept for new loans with comparable risk because of deterioration in the borrower's financial condition. Such loan modifications are handled on a case-by-case basis and are negotiated to achieve mutually agreeable terms that maximize loan collectability and meet the borrower’s financial needs. Modifications may include changes to one or more terms of the loan, including, but not limited to: (i) payment deferral; (ii) a reduction in the stated interest rate for the remaining contractual life of the loan; (iii) an extension of the loan’s original contractual term at a stated interest rate lower than the current market rate for a new loan with similar risk; (iv) capitalization of interest; or (v) forgiveness of principal or interest. TDRs may either be accruing or placed on non-accrual status (and reported as non-accrual loans) depending upon the loan’s specific circumstances, including the nature and extent of the related modifications. TDRs on non-accrual status remain classified as such until the loan qualifies for return to accrual status. Loans qualify for return to accrual status once they have demonstrated performance with the restructured terms of the loan agreement for a minimum of six months in the case of a commercial loan or, in the case of a retail loan, when the loan is less than 90 days past due. Loans may continue to be reported as TDRs after they are returned to accrual status. In accordance with regulatory guidance, residential mortgage and home equity loans restructured in connection with the borrower’s bankruptcy and meeting certain criteria are also required to be classified as TDRs, included in non-accrual loans and written down to the estimated collateral value, regardless of delinquency status. At March 31, 2020 and December 31, 2019, People’s United’s recorded investment in loans classified as TDRs totaled $178.9 million and $177.0 million, respectively. The related ACL was $13.1 million at March 31, 2020 and $4.3 million at December 31, 2019. Interest income recognized on TDRs totaled $1.3 million and $1.6 million for the three months ended March 31, 2020 and 2019, respectively. Funding under commitments to lend additional amounts to borrowers with loans classified as TDRs was immaterial for the three months ended March 31, 2020 and 2019. Loans that were modified and classified as TDRs during the three months ended March 31, 2020 and 2019 principally involve reduced payment and/or payment deferral, extension of term (generally no more than two years for commercial loans and five years for retail loans) and/or a temporary reduction of interest rate (generally less than 200 basis points). The CARES Act and guidance recently issued by the Federal banking agencies provides that certain short-term loan modifications to borrowers experiencing financial distress as a result of the economic impacts created by the COVID-19 pandemic are not required to be treated as TDRs under GAAP. As such, the Company suspended TDR accounting for COVID-19 related loan modifications meeting the loan modification criteria set forth under the CARES Act or as specified in the regulatory guidance. Further, loans granted payment deferrals related to COVID-19 are not required to be reported as past due or placed on non-accrual status (provided the loans were not past due or on non-accrual status prior to the deferral). The following tables summarize, by class of loan, the recorded investments in loans modified as TDRs during the three months ended March 31, 2020 and 2019. For purposes of this disclosure, recorded investments represent amounts immediately prior to and subsequent to the restructuring. Three Months Ended March 31, 2020 (dollars in millions) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial: Commercial real estate (1) 5 $ 3.7 $ 3.7 Commercial and industrial (2) 10 9.0 9.0 Equipment financing (3) 9 3.1 3.1 MWABL — — — Total 24 15.8 15.8 Retail: Residential mortgage (4) 13 6.2 6.2 Home equity (5) 17 2.1 2.1 Other consumer — — — Total 30 8.3 8.3 Total 54 $ 24.1 $ 24.1 (1) Represents the following concessions: extension of term (4 contracts; recorded investment of $3.2 million); or a reduced payment and/or payment deferral (1 contract; recorded investment of $0.5 million). (2) Represents the following concessions: extension of term (5 contracts; recorded investment of $7.4 million); reduced payment and/or payment deferral (1 contract; recorded investment of $0.3 million); or a combination of concessions (4 contract; recorded investment of $1.3 million). (3) Represents the following concessions: extension of term (1 contract; recorded investment of $1.2 million); reduced payment and/or payment deferral (5 contracts; recorded investment of $0.5 million); or a combination of concessions (3 contracts; recorded investment of $1.4 million). (4) Represents the following concessions: loans restructured through bankruptcy (3 contracts; recorded investment of $0.6 million); reduced payment and/or payment deferral (9 contracts; recorded investment of $5.5 million); or a combination of concessions (1 contract; recorded investment of $0.1 million). (5) Represents the following concessions: loans restructured through bankruptcy (5 contracts; recorded investment of $0.5 million); reduced payment and/or payment deferral (1 contract; recorded investment of $0.1 million); or a combination of concessions (11 contracts; recorded investment of $1.5 million). Three Months Ended March 31, 2019 (dollars in millions) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial: Commercial real estate (1) 2 $ 3.0 $ 3.0 Commercial and industrial (2) 4 1.4 1.4 Equipment financing (3) 14 7.3 7.3 Total 20 11.7 11.7 Retail: Residential mortgage (4) 20 5.6 5.6 Home equity (5) 22 2.1 2.1 Other consumer — — — Total 42 7.7 7.7 Total 62 $ 19.4 $ 19.4 (1) Represents the following concession: reduced payment and/or payment deferral (2 contracts; recorded investment of $3.0 million). (2) Represents the following concessions: extension of term (4 contracts; recorded investment of $1.4 million). (3) Represents the following concessions: extension of term (8 contracts; recorded investment of $6.6 million); reduced payment and/or payment deferral (5 contracts; recorded investment of $0.5 million); or a combination of concessions (1 contract; recorded investment of $0.2 million). (4) Represents the following concessions: loans restructured through bankruptcy (9 contracts; recorded investment of $1.1 million); reduced payment and/or payment deferral (5 contracts; recorded investment of $2.2 million); or a combination of concessions (6 contracts; recorded investment of $2.3 million). (5) Represents the following concessions: loans restructured through bankruptcy (9 contracts; recorded investment of $0.6 million); reduced payment and/or payment deferral (3 contracts; recorded investment of $0.5 million); or a combination of concessions (10 contracts; recorded investment of $1.0 million). The following is a summary, by class of loan, of information related to TDRs completed within the previous 12 months that subsequently defaulted during the three months ended March 31, 2020 and 2019. For purposes of this disclosure, the previous 12 months is measured from April 1 of the respective prior year and a default represents a previously-modified loan that became past due 30 days or more during the three months ended March 31, 2020 or 2019. Three Months Ended March 31, 2020 2019 (dollars in millions) Number of Contracts Recorded Investment as of Period End Number of Contracts Recorded Investment as of Period End Commercial: Commercial real estate — $ — — $ — Commercial and industrial 1 0.1 — — Equipment financing 4 2.5 2 2.9 MWABL — — — — Total 5 2.6 2 2.9 Retail: Residential mortgage 3 1.3 3 1.3 Home equity 1 — 2 0.4 Other consumer — — — — Total 4 1.3 5 1.7 Total 9 $ 3.9 7 $ 4.6 Loan Charge-Offs The Company’s charge-off policies, which comply with standards established by banking regulators, are consistently applied from period to period. Charge-offs are recorded on a monthly basis. Partially charged-off loans continue to be evaluated on a monthly basis and additional charge-offs or credit loss provisions may be recorded on the remaining loan balance based on the same criteria. For unsecured consumer loans, charge-offs are generally recorded when the loan is deemed to be uncollectible or 120 days past due, whichever occurs first. For consumer loans secured by real estate, including residential mortgage loans, charge-offs are generally recorded when the loan is deemed to be uncollectible or 180 days past due, whichever occurs first, unless it can be clearly demonstrated that repayment will occur regardless of the delinquency status. Factors that demonstrate an ability to repay may include: (i) a loan that is secured by adequate collateral and is in the process of collection; (ii) a loan supported by a valid guarantee or insurance; or (iii) a loan supported by a valid claim against a solvent estate. For commercial loans, a charge-off is recorded when the Company determines that it will not collect all amounts contractually due based on the fair value of the collateral less cost to sell. The decision whether to charge-off all or a portion of a loan rather than to record a specific or general loss allowance is based on an assessment of all available information that aids in determining the loan’s net realizable value. Typically, this involves consideration of both (i) the fair value of any collateral securing the loan, including whether the estimate of fair value has been derived from an appraisal or other market information and (ii) other factors affecting the likelihood of repayment, including the existence of guarantees and insurance. If the amount by which the Company’s recorded investment in the loan exceeds its net realizable value is deemed to be a confirmed loss, a charge-off is recorded. Otherwise, a specific or general reserve is established, as applicable. The comparatively low level of net loan charge-offs in recent years, in terms of absolute dollars and as a percentage of average total loans, may not be sustainable in the future. Credit Quality Indicators As part of the on-going monitoring of the credit quality of the loan portfolio, management tracks certain credit quality indicators including trends related to: (i) internal Commercial loan risk ratings; (ii) internal Retail loan risk classification; and (iii) non-accrual loans (see details above). Commercial Credit Quality Indicators The Company utilizes an internal loan risk rating system as a means of monitoring portfolio credit quality and identifying both problem and potential problem loans. Under the Company’s risk rating system, loans not meeting the criteria for problem and potential problem loans as specified below are considered to be “Pass”-rated loans. Problem and potential problem loans are classified as either “Special Mention,” “Substandard” or “Doubtful.” Loans that do not currently expose the Company to sufficient enough risk of loss to warrant classification as either Substandard or Doubtful, but possess weaknesses that deserve management’s close attention, are classified as Special Mention. Substandard loans represent those credits characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. Loans classified as Doubtful possess all the weaknesses inherent in those classified Substandard with the added characteristic that collection or liquidation in full, on the basis of existing facts, conditions and values, is highly questionable and/or improbable. Risk ratings on commercial loans are subject to ongoing monitoring by lending and credit personnel with such ratings updated annually or more frequently, if warranted. The Company’s internal Loan Review function is responsible for independently evaluating the appropriateness of those credit risk ratings in connection with its cyclical reviews, the approach to which is risk-based and determined by reference to underlying portfolio credit quality and the results of prior reviews. Differences in risk ratings noted in conjunction with such periodic portfolio loan reviews, if any, are reported to management each month. The following table presents Commercial loan risk ratings, by class of loan and year of origination, as of March 31, 2020: (in millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Commercial real estate: Pass $ 335.3 $ 1,762.3 $ 1,730.4 $ 1,703.1 $ 1,584.0 $ 6,615.0 $ 380.7 $ 14,110.8 Special Mention — 8.7 91.4 28.0 38.6 115.3 2.4 284.4 Substandard 2.3 29.3 22.9 29.2 6.6 161.6 2.9 254.8 Doubtful — — — — — 1.6 — 1.6 Total $ 337.6 $ 1,800.3 $ 1,844.7 $ 1,760.3 $ 1,629.2 $ 6,893.5 $ 386.0 $ 14,651.6 Commercial and industrial: Pass $ 674.1 $ 1,876.3 $ 1,015.3 $ 801.6 $ 635.6 $ 1,930.1 $ 1,635.0 $ 8,568.0 Special Mention 2.1 11.5 22.3 6.1 39.8 63.1 41.9 186.8 Substandard 0.7 11.5 57.0 37.0 12.3 127.4 93.5 339.4 Doubtful — — — 0.6 1.2 — 1.7 3.5 Total $ 676.9 $ 1,899.3 $ 1,094.6 $ 845.3 $ 688.9 $ 2,120.6 $ 1,772.1 $ 9,097.7 Equipment financing: Pass $ 556.4 $ 1,843.0 $ 1,068.9 $ 587.7 $ 303.1 $ 164.3 $ — $ 4,523.4 Special Mention 13.5 33.7 16.1 10.9 4.4 1.7 — 80.3 Substandard 45.2 161.2 101.8 56.5 13.1 31.2 — 409.0 Doubtful — — — — — — — — Total $ 615.1 $ 2,037.9 $ 1,186.8 $ 655.1 $ 320.6 $ 197.2 $ — $ 5,012.7 MWABL: Pass $ 2.6 $ 10.8 $ 15.0 $ 6.6 $ 21.0 $ 62.7 $ 2,697.0 $ 2,815.7 Special Mention — 7.3 — — — — 68.6 75.9 Substandard — — — 1.9 0.7 1.9 51.9 56.4 Doubtful — — — — — — — — Total $ 2.6 $ 18.1 $ 15.0 $ 8.5 $ 21.7 $ 64.6 $ 2,817.5 $ 2,948.0 Retail Credit Quality Indicators Pools of Retail loans with similar risk and loss characteristics are also assessed for losses. These loan pools include residential mortgage, home equity and other consumer loans that are not assigned individual loan risk ratings. Rather, the assessment of these portfolios is based upon a consideration of recent historical loss experience, broader portfolio indicators, including trends in delinquencies, non-accrual loans and portfolio concentrations, and portfolio-specific risk characteristics, the combination of which determines whether a loan is classified as “High”, “Moderate” or “Low” risk. The portfolio-specific risk characteristics considered include: (i) collateral values/loan-to-value (“LTV”) ratios (above and below 70%); (ii) borrower credit scores under the FICO scoring system (above and below a score of 680); and (iii) other relevant portfolio risk elements such as income verification at the time of underwriting (stated income vs. non-stated income) and the property’s intended use (owner-occupied, non-owner occupied, second home, etc.). In classifying a loan as either “High”, “Moderate” or “Low” risk, the combination of each of the aforementioned risk characteristics is considered for that loan, resulting, effectively, in a “matrix approach” to its risk classification. These risk classifications are reviewed quarterly to ensure that they continue to be appropriate in light of changes within the portfolio and/or economic indicators as well as other industry developments. For example, to the extent LTV ratios exceed 70% (reflecting a weaker collateral position for the Company) or borrower FICO scores are less than 680 (reflecting weaker financial standing and/or credit history of the customer), the loans are considered to have an increased level of inherent loss. As a result, a loan with a combination of these characteristics would generally be classified as “High” risk. Conversely, as LTV ratios decline (reflecting a stronger collateral position for the Company) or borrower FICO scores exceed 680 (reflecting stronger financial standing and/or credit history of the customer), the loans are considered to have a decreased level of inherent loss. A loan with a combination of these characteristics would generally be classified as “Low” risk. This analysis also considers (i) the extent of underwriting that occurred at the time of origination (direct income verification provides further support for credit decisions) and (ii) the property’s intended use (owner-occupied properties are less likely to default compared to ‘investment-type’ non-owner occupied properties, second homes, etc.). Loans not otherwise deemed to be “High” or “Low” risk are classified as “Moderate” risk. LTV ratios and FICO scores are determined at origination and updated periodically throughout the life of the loan. LTV ratios are updated for loans 90 days past due and FICO scores are updated for the entire portfolio quarterly. The portfolio stratification (“High”, “Moderate” and “Low” risk) and identification of the corresponding credit quality indicators also occurs quarterly. The following table presents Retail loan risk classification, by class of loan and year of origination, as of March 31, 2020: (in millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Residential mortgage: Low Risk $ 51.5 $ 400.9 $ 423.9 $ 560.7 $ 1,130.5 $ 1,937.1 $ — $ 4,504.6 Moderate Risk 132.7 640.0 835.4 967.7 928.3 1,335.1 — 4,839.2 High Risk 26.4 79.8 117.6 114.1 104.8 295.4 — 738.1 Total $ 210.6 $ 1,120.7 $ 1,376.9 $ 1,642.5 $ 2,163.6 $ 3,567.6 $ — $ 10,081.9 Home equity: Low Risk $ — $ — $ — $ — $ — $ 31.7 $ 335.2 $ 366.9 Moderate Risk 0.4 15.3 12.1 6.1 3.2 35.2 689.5 761.8 High Risk 2.0 27.9 83.0 68.0 27.5 14.3 998.5 1,221.2 Total $ 2.4 $ 43.2 $ 95.1 $ 74.1 $ 30.7 $ 81.2 $ 2,023.2 $ 2,349.9 Other consumer: Low Risk $ 1.6 $ 10.0 $ 6.3 $ 1.5 $ 0.5 $ 4.8 $ — $ 24.7 Moderate Risk — 0.1 0.2 0.1 0.2 5.3 — 5.9 High Risk 3.3 58.2 42.5 3.8 0.8 3.0 — 111.6 Total $ 4.9 $ 68.3 $ 49.0 $ 5.4 $ 1.5 $ 13.1 $ — $ 142.2 The following tables present Commercial and Retail credit quality indicators as of December 31, 2019: (in millions) Commercial Real Estate Commercial and Industrial Equipment Financing Total Commercial: Pass $ 14,222.3 $ 10,391.7 $ 4,433.5 $ 29,047.5 Special mention 334.3 330.4 76.5 741.2 Substandard 202.6 315.8 400.4 918.8 Doubtful 3.1 3.7 — 6.8 Total $ 14,762.3 $ 11,041.6 $ 4,910.4 $ 30,714.3 (in millions) Residential Mortgage Home Equity Other Consumer Total Retail: Low risk $ 4,410.0 $ 747.3 $ 24.9 $ 5,182.2 Moderate risk 4,958.3 548.5 5.9 5,512.7 High risk 949.8 1,110.7 126.4 2,186.9 Total $ 10,318.1 $ 2,406.5 $ 157.2 $ 12,881.8 Other Real Estate Owned and Repossessed Assets (included in Other Assets) Other real estate owned (“REO”) was comprised of residential and commercial properties totaling $9.5 million and $7.3 million, respectively, at March 31, 2020, and $11.9 million and $7.3 million, respectively, at December 31, 2019. Repossessed assets totaled $4.6 million and $4.2 million at March 31, 2020 and December 31, 2019, respectively. Loans Held for Sale Loans held-for-sale at March 31, 2020 and December 31, 2019 included newly-originated residential mortgage loans with carrying amounts of $19.2 million and $19.7 million, respectively. At December 31, 2019, loans held-for-sale also included $333.7 million of consumer loans and $157.9 million of commercial loans previously acquired in the United Financial Bancorp, Inc. acquisition. All of the consumer and commercial loans were sold during the first quarter of 2020, resulting in a gain, net of expenses, of $16.9 million.

Allowance For Credit Losses

Allowance For Credit Losses	3 Months Ended
	Mar. 31, 2020
Allowance for Credit Loss [Abstract]
Allowance for Credit Losses	NOTE 4. ALLOWANCE FOR CREDIT LOSSES On January 1, 2020, the Company adopted the CECL standard which requires the measurement of expected credit losses for financial assets measured at amortized cost, including loans, and certain off-balance-sheet credit exposures. Allowance for Credit Losses – Loans Under the CECL standard, the Company determines the ACL on loans based upon a consideration of its historical portfolio loss experience, current borrower-specific risk characteristics, forecasts of future economic conditions and other relevant factors. The allowance is measured on a collective (pool) basis when similar risk characteristics exist. Loans that do not share common risk characteristics are evaluated on an individual basis and are excluded from the collective evaluation. The Company’s loan portfolio segments include Commercial and Retail and each of these segments comprises multiple loan classes, which are characterized by similarities in initial measurement, risk attributes, and the manner in which credit risk is monitored and assessed. The Commercial loan portfolio segment is comprised of the commercial real estate, commercial and industrial, equipment financing and MWABL loan classes. The Retail loan portfolio segment is comprised of the residential mortgage, home equity and other consumer loan classes. Common characteristics and risk profiles include the type/purpose of loan and historical/expected credit loss patterns. The Company periodically reassesses each pool to ensure the loans within the pool continue to share similar characteristics and risk profiles and to determine whether further segmentation is necessary. The ACL on loans represents management’s current estimate of lifetime expected credit losses inherent in the loan portfolio at the balance sheet date. As such, the estimate of expected credit losses is dependent upon portfolio size, composition and credit quality, as well as economic conditions and forecasts existing at that time. Expected future losses are estimated for the loan's entire contractual term adjusted for anticipated prepayments, as appropriate. The contractual term excludes expected extensions, renewals, and modifications unless (i) management has a reasonable expectation that a TDR will be executed with an individual borrower or (ii) such extension or renewal options are not unconditionally cancellable by the Company and, in such cases, the borrower is likely to meet applicable conditions and likely to request extension or renewal. Credit loss expense related to loans reflects the totality of actions taken on all loans for a particular period including any necessary increases or decreases in the allowance related to changes in credit loss expectations associated with specific loans or pools of loans. Portions of the allowance may be allocated for specific credits; however, the entire allowance is available for any credit that, in management’s judgment, should be charged-off. While management utilizes its best judgment and information available, the ultimate appropriateness of the allowance is dependent upon a variety of factors beyond management's control, including the performance of the loan portfolio, changes in interest rates and the broader economy. The ACL on loans is comprised of three components: (i) quantitative (formulaic) reserves; (ii) qualitative (judgmental) reserves; and (iii) individual loan reserves. Quantitative Component Management estimates the quantitative component by projecting (i) probability-of-default, representing the likelihood that a loan will stop performing/default (“PD”), (ii) loss-given-default, representing the expected loss rate for loans in default (“LGD”) and (iii) exposure-at-default (“EAD”), representing the estimated outstanding principal balance of the loans upon default, based on economic parameters for each month of a loan’s remaining contractual term. Expected credit losses for the quantitative component are calculated as the product of the PD, LGD and EAD. Historical credit experience provides the basis for the estimation of expected credit losses, with adjustments made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, delinquency levels and terms, as well as for changes in the economic environment over a reasonable and supportable forecast period. The Company utilizes a two-year reasonable and supportable forecast period followed by a one-year period over which estimated losses revert to historical loss experience for the remaining life of the loan. PDs are estimated by analyzing internal data related to the historical performance of each loan pool over an economic cycle. PDs are adjusted to reflect the current impact of certain macroeconomic variables as well as their expected changes over the reasonable and supportable forecast period. The LGD is based on historical losses for each loan pool, adjusted to reflect the current impact of certain macroeconomic variables as well as their expected changes over a two-year forecast period. EAD is estimated using a linear regression model that estimates the average percentage of the loan balance that remains at the time of a default event. The macroeconomic variables utilized as inputs in the Company’s quantitative modeling process were selected primarily based on their relevance and correlation to historical credit losses. By reverting such modeling inputs to their historical mean and considering loan/borrower specific attributes, the Company’s quantitative models yield a measurement of expected credit losses reflective of average historical loss rates for periods subsequent to the twelve-month reversion period. This same forecast/reversion period is used for all macroeconomic variables employed in all of the Company’s models. The measurement of expected credit losses is impacted by loan/borrower attributes and certain macroeconomic variables. Significant loan/borrower attributes utilized in the Company’s quantitative modeling include, among other things: (i) origination date; (ii) maturity date; (iii) payment type; (iv) collateral type and amount; (v) current risk rating; (vi) current unpaid balance and commitment utilization rate; and (vii) payment status/delinquency history. Significant macroeconomic variables utilized in the Company’s quantitative modeling include, among other things: (i) U.S. Gross Domestic Product; (ii) selected market interest rates including U.S. Treasury rates, Prime rate, 30-year fixed mortgage rate, BBB corporate bond rate (spread), among others; (iii) unemployment rates; and (iv) commercial and residential property prices. In establishing its estimate of expected credit losses, the Company typically employs three separate, externally-sourced forward-looking economic scenarios. Those scenarios, which range from more benign to more severe, represent a ‘most likely outcome’ (the “Baseline” scenario) and two less likely scenarios referred to as the “Upside” scenario and the “Downside” scenario. Each scenario is assigned a weighting with a majority of the weighting placed on the Baseline scenario and lower weights placed on both the Upside and Downside scenarios. The weighting assigned by management is based on the economic outlook and available information at the reporting date. The resultant weighted estimate of expected credit losses is compared to the result of the Baseline scenario with the difference included as an element of the qualitative component (see below). The Company recognizes an approach using three scenarios may be insufficient in certain economic environments. This may result in a change to the weighting assigned to the three scenarios or the inclusion of additional scenarios. For instance, as a result of the deterioration in economic conditions caused by the spread of the COVID-19 pandemic during the first quarter of 2020, and the corresponding increase in economic uncertainty, a fourth forward-looking economic scenario (the “Severe Downside” scenario) was also considered for purposes of estimating expected credit losses at March 31, 2020. All four scenarios reflected the effects of the COVID-19 pandemic as well as the United States’ monetary and fiscal response. Each scenario was assigned a weighting with the majority of the weighting placed on the Baseline scenario and lower weights placed on each of the Upside, Downside and Severe Downside scenarios. The weighting assigned by management was based on the economic outlook and available information at that date. Qualitative Component The ACL on loans also includes qualitative considerations related to idiosyncratic risk factors, changes in current economic conditions that may not be reflected in quantitatively-derived results, and other relevant factors. These qualitative adjustments may increase or decrease management's estimate of expected credit losses by a calculated percentage or amount based upon the estimated level of risk. The various risks that may be considered in making qualitative adjustments include, among other things, the impact of: (i) changes in lending policies and procedures, including changes in underwriting standards and practices for collections, write-offs, and recoveries; (ii) actual and expected changes in international, national, regional, and local economic and business conditions and developments that affect collectability of the loan pools; (iii) changes in the nature and volume of the loan pools and in the terms of the underlying loans; (iv) changes in the experience, ability, and depth of our lending management and staff; (v) changes in volume and severity of past due financial assets, the volume of non-accrual assets, and the volume and severity of adversely classified or graded assets; (vi) changes in the quality of our credit review function; (vii) changes in the value of the underlying collateral for loans that are non-collateral dependent; (viii) the existence, growth, and effect of any concentrations of credit; and (ix) other external factors such as the regulatory, legal and technological environments, competition and events, such as natural disasters or health pandemics. While the Company’s loss estimation methodologies strive to reflect all relevant risk factors, uncertainty exists associated with, but not limited to, potential imprecision in the estimation process due to the inherent time lag of obtaining information and normal variations between estimates and actual outcomes, including with respect to forward-looking economic forecasts. The qualitative component is designed to provide coverage for losses attributable to such risks. Individual Component In some cases, management may determine that an individual loan exhibits unique risk characteristics which differentiate that loan from other loans within the pool. In such cases, the loans are evaluated for expected credit losses on an individual basis and excluded from the collective evaluation. Specific allocations of the ACL are determined by analyzing the borrower’s ability to repay amounts owed, collateral deficiencies, the relative risk of the loan and economic conditions affecting the borrower’s industry, among other things. For collateral dependent loans, expected credit losses are based on the fair value of the collateral at the measurement date, adjusted for estimated selling costs if satisfaction of the loan depends on the sale of the collateral. The Company reevaluates the fair value of collateral supporting collateral dependent loans on a quarterly basis. Specific allocations of the ACL for loans evaluated on an individual basis totaled $8.9 million at March 31, 2020. The following tables present a summary, by loan portfolio segment, of activity in the ACL for the three months ended March 31, 2020 and 2019: Three months ended March 31, 2020 (in millions) Commercial Retail Total Balance at beginning of period, $ 217.9 $ 28.7 $ 246.6 CECL transition adjustment (17.3) 89.5 72.2 Charge-offs (9.7) (2.9) (12.6) Recoveries 1.4 0.6 2.0 Net loan charge-offs (8.3) (2.3) (10.6) Provision for credit losses 19.5 14.0 33.5 Balance at end of period $ 211.8 $ 129.9 $ 341.7 Three months ended March 31, 2019 (in millions) Commercial Retail Total Balance at beginning of period $ 209.5 $ 30.9 $ 240.4 Charge-offs (6.4) (1.1) (7.5) Recoveries 1.4 1.0 2.4 Net loan charge-offs (5.0) (0.1) (5.1) Provision for credit losses 4.5 1.1 5.6 Balance at end of period $ 209.0 $ 31.9 $ 240.9 Allowance for Credit Losses – Off-Balance-Sheet Exposures An ACL on off-balance-sheet exposures is reported in other liabilities in the Consolidated Statements of Condition. This liability represents an estimate of expected credit losses arising from off-balance-sheet exposures such as letters of credit, guarantees and unfunded commitments to extend credit. The process for measuring lifetime expected credit losses on such exposures is consistent with that for Commercial and Retail loans as discussed above (as applicable), but is subject to an additional estimate reflecting the likelihood that funding will occur. Adjustments to the liability are reported as a component of credit loss expense. No liability is recognized for off-balance-sheet credit exposures that are unconditionally cancellable. The following table summarizes the changes in the ACL on off-balance sheet credit exposures: (in millions) Three Months Ended March 31, 2020 Balance at beginning of the period $ 5.6 CECL transition adjustment 14.5 Balance at beginning of period, adjusted 20.1 Provision charged (credited) to income 0.6 Balance at end of period $ 20.7

Leases

Leases	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Leases	NOTE 5. LEASES Effective January 1, 2019, People's United adopted new accounting guidance relating to real estate (primarily branch locations) and office equipment subject to non-cancelable operating lease agreements entered into by the Company as lessee. The amount of the right-of-use ("ROU") assets and corresponding lease liabilities recorded upon adoption were based, primarily, on the present value of unpaid future minimum lease payments, the amount of which is dependent upon the population of leases in effect at the date of adoption, as well as assumptions with respect to renewals and/or extensions and the interest rate used to discount the future lease obligations. As it relates to lease agreements entered into with equipment financing customers, and for which the Company acts as lessor, the impact principally relates to the definition of eligible initial direct costs ("IDC") under the new guidance. Specifically, the standard maintains a narrower definition of IDC which will result in the Company recognizing immediately (rather than deferring) certain lease origination-related expenses. Such expenses would be offset by the recognition of a higher yield on the underlying leases over their contractual term. Upon adoption, the Company recognized (i) operating lease liabilities totaling $268.8 million, based on the present value of the remaining minimum lease payments, determined using a discount rate as of the effective date and (ii) corresponding ROU assets totaling $248.5 million, based upon the operating lease liabilities, adjusted for prepaid and deferred rent, and liabilities associated with lease termination costs. Lessor Arrangements People's United provides equipment financing to its customers through a variety of lessor arrangements, some of which may include options to renew and/or for the lessee to purchase the leased equipment at the end of the lease term. Direct financing leases and sales-type leases (collectively, "lease financing receivables") are carried at the aggregate of lease payments receivable plus the estimated residual value of the leased assets and any initial direct costs incurred to originate these leases , less unearned income, which is accreted to interest income over the lease term using the interest method. The residual value component of a lease financing receivable represents the estimated fair value of the leased equipment at the end of the lease term. In establishing residual value estimates, the Company may rely on industry data, historical experience, independent appraisals and, where appropriate, information regarding product life cycle, product upgrades and competing products. Upon expiration of a lease, residual assets are remarketed, resulting in an extension of the lease by the lessee, a lease to a new customer or purchase of the residual asset by the lessee or another party. Impairment of residual values arises if the expected fair value is less than the carrying amount. The Company assesses its net investment in lease financing receivables (including residual values) for impairment on a quarterly basis with any impairment losses recognized in accordance with the impairment guidance for financial instruments. As such, net investment in lease financing receivables may be reduced by an ACL with changes recognized as provision expense. The composition of the Company’s total net investment in lease financing receivables included within equipment financing loans in the Consolidated Statements of Condition was as follows: (in millions) March 31, 2020 December 31, 2019 Lease payments receivable $ 1,451.7 $ 1,417.1 Estimated residual value of leased assets 128.7 128.0 Gross investment in lease financing receivables 1,580.4 1,545.1 Plus: Deferred origination costs 13.0 13.4 Less: Unearned income (158.5) (156.9) Total net investment in lease financing receivables $ 1,434.9 $ 1,401.6 The contractual maturities of the Company's lease financing receivables were as follows: (in millions) March 31, 2020 2020 (1) $ 408.6 2021 448.4 2022 340.8 2023 208.7 2024 117.7 Later years 56.2 Total $ 1,580.4 (1) Contractual maturities for the nine months remaining in 2020. Operating lease income, generated in connection with operating leases for which the Company acts as a lessor, is recognized on a straight-line basis over the lease term as a component of non-interest income in the Consolidated Statements of Income. Depreciation expense for assets under operating leases, which are included in other assets in the Consolidated Statements of Condition, is generally recorded on a straight-line basis over the lease term as a component of non-interest expense in the Consolidated Statements of Income. The following table summarizes People's United's total lease income: Three Months Ended (in millions) 2020 2019 Lease financing receivables $ 17.6 $ 15.5 Operating leases 12.6 12.7 Total lease income $ 30.2 $ 28.2 Lessee Arrangements Substantially all of the Company’s lessee arrangements represent non-cancelable operating leases for real estate (primarily branch locations) and office equipment with terms extending through 2054. Under these arrangements, People's United records ROU assets and corresponding lease liabilities at lease commencement. Lease liabilities are recognized based on the present value of the remaining lease payments and discounted using the Company’s incremental borrowing rate for borrowings of similar term. ROU assets initially equal the related lease liability, adjusted for any lease payments made prior to the lease commencement and any lease incentives. Portions of certain properties are subleased for terms extending through 2028. At lease commencement, the Company considers renewal or termination options in the determination of the term of the lease. If it is reasonably certain that a renewal or termination option will be exercised, the effects of such options are included in the determination of the expected lease term. All leases are recorded with the exception of leases with an initial term of twelve months or less for which the Company made the short-term lease election. Within the Consolidated Statements of Condition, ROU assets are reported in other assets and the related lease liabilities are reported in other liabilities. In recognizing ROU assets and related lease liabilities, lease and non-lease components (such as taxes, insurance and common area maintenance costs) are accounted for separately as such amounts are generally readily determinable under the Company's lease contracts. Lease expense is recognized on a straight-line basis over the lease term and is recorded within occupancy and equipment expense in the Consolidated Statements of Income. Variable lease payments, which generally relate to the non-lease components noted above, are expensed as incurred. The following tables provide the components of lease cost and supplemental information: Three Months Ended (in millions) 2020 2019 Operating lease cost $ 16.7 $ 15.3 Variable lease cost 3.1 2.3 Finance lease cost 0.1 — Sublease income (0.5) (0.4) Net lease cost $ 19.4 $ 17.2 (dollars in millions) March 31, 2020 December 31, 2019 Lease ROU assets: Operating leases $ 275.9 $ 276.6 Finance leases 2.5 2.6 Lease liabilities: Operating leases 307.5 307.9 Finance leases 5.2 5.3 Weighted-average discount rate: Operating leases 3.12 % 3.13 % Finance leases 2.58 2.58 Weighted-average remaining lease term (in years): Operating leases 7.8 7.7 Finance leases 11.9 12.2 Three Months Ended (in millions) 2020 2019 Cash payments included in the measurement of lease liabilities: Reported in operating cash from operating leases $ 17.1 $ 15.4 Reported in financing cash from finance leases 0.1 — ROU assets obtained in exchange for lessee: Operating lease liabilities (1) 14.3 10.3 Finance lease liabilities (1) — — (1) Excludes related transition adjustment recorded during three months ended March 31, 2019 ( see above ). The contractual maturities of the Company's lease liabilities as of March 31, 2020 were as follows: (in millions) Operating Leases Finance Leases 2020 (1) $ 50.4 $ 0.4 2021 65.3 0.5 2022 47.7 0.5 2023 36.0 0.5 2024 30.0 0.5 Later years 121.0 3.7 Total lease payments 350.4 6.1 Less: Interest (42.9) (0.9) Total lease liabilities $ 307.5 $ 5.2 (1) Contractual maturities for the nine months remaining in 2020.
Leases	NOTE 5. LEASES Effective January 1, 2019, People's United adopted new accounting guidance relating to real estate (primarily branch locations) and office equipment subject to non-cancelable operating lease agreements entered into by the Company as lessee. The amount of the right-of-use ("ROU") assets and corresponding lease liabilities recorded upon adoption were based, primarily, on the present value of unpaid future minimum lease payments, the amount of which is dependent upon the population of leases in effect at the date of adoption, as well as assumptions with respect to renewals and/or extensions and the interest rate used to discount the future lease obligations. As it relates to lease agreements entered into with equipment financing customers, and for which the Company acts as lessor, the impact principally relates to the definition of eligible initial direct costs ("IDC") under the new guidance. Specifically, the standard maintains a narrower definition of IDC which will result in the Company recognizing immediately (rather than deferring) certain lease origination-related expenses. Such expenses would be offset by the recognition of a higher yield on the underlying leases over their contractual term. Upon adoption, the Company recognized (i) operating lease liabilities totaling $268.8 million, based on the present value of the remaining minimum lease payments, determined using a discount rate as of the effective date and (ii) corresponding ROU assets totaling $248.5 million, based upon the operating lease liabilities, adjusted for prepaid and deferred rent, and liabilities associated with lease termination costs. Lessor Arrangements People's United provides equipment financing to its customers through a variety of lessor arrangements, some of which may include options to renew and/or for the lessee to purchase the leased equipment at the end of the lease term. Direct financing leases and sales-type leases (collectively, "lease financing receivables") are carried at the aggregate of lease payments receivable plus the estimated residual value of the leased assets and any initial direct costs incurred to originate these leases , less unearned income, which is accreted to interest income over the lease term using the interest method. The residual value component of a lease financing receivable represents the estimated fair value of the leased equipment at the end of the lease term. In establishing residual value estimates, the Company may rely on industry data, historical experience, independent appraisals and, where appropriate, information regarding product life cycle, product upgrades and competing products. Upon expiration of a lease, residual assets are remarketed, resulting in an extension of the lease by the lessee, a lease to a new customer or purchase of the residual asset by the lessee or another party. Impairment of residual values arises if the expected fair value is less than the carrying amount. The Company assesses its net investment in lease financing receivables (including residual values) for impairment on a quarterly basis with any impairment losses recognized in accordance with the impairment guidance for financial instruments. As such, net investment in lease financing receivables may be reduced by an ACL with changes recognized as provision expense. The composition of the Company’s total net investment in lease financing receivables included within equipment financing loans in the Consolidated Statements of Condition was as follows: (in millions) March 31, 2020 December 31, 2019 Lease payments receivable $ 1,451.7 $ 1,417.1 Estimated residual value of leased assets 128.7 128.0 Gross investment in lease financing receivables 1,580.4 1,545.1 Plus: Deferred origination costs 13.0 13.4 Less: Unearned income (158.5) (156.9) Total net investment in lease financing receivables $ 1,434.9 $ 1,401.6 The contractual maturities of the Company's lease financing receivables were as follows: (in millions) March 31, 2020 2020 (1) $ 408.6 2021 448.4 2022 340.8 2023 208.7 2024 117.7 Later years 56.2 Total $ 1,580.4 (1) Contractual maturities for the nine months remaining in 2020. Operating lease income, generated in connection with operating leases for which the Company acts as a lessor, is recognized on a straight-line basis over the lease term as a component of non-interest income in the Consolidated Statements of Income. Depreciation expense for assets under operating leases, which are included in other assets in the Consolidated Statements of Condition, is generally recorded on a straight-line basis over the lease term as a component of non-interest expense in the Consolidated Statements of Income. The following table summarizes People's United's total lease income: Three Months Ended (in millions) 2020 2019 Lease financing receivables $ 17.6 $ 15.5 Operating leases 12.6 12.7 Total lease income $ 30.2 $ 28.2 Lessee Arrangements Substantially all of the Company’s lessee arrangements represent non-cancelable operating leases for real estate (primarily branch locations) and office equipment with terms extending through 2054. Under these arrangements, People's United records ROU assets and corresponding lease liabilities at lease commencement. Lease liabilities are recognized based on the present value of the remaining lease payments and discounted using the Company’s incremental borrowing rate for borrowings of similar term. ROU assets initially equal the related lease liability, adjusted for any lease payments made prior to the lease commencement and any lease incentives. Portions of certain properties are subleased for terms extending through 2028. At lease commencement, the Company considers renewal or termination options in the determination of the term of the lease. If it is reasonably certain that a renewal or termination option will be exercised, the effects of such options are included in the determination of the expected lease term. All leases are recorded with the exception of leases with an initial term of twelve months or less for which the Company made the short-term lease election. Within the Consolidated Statements of Condition, ROU assets are reported in other assets and the related lease liabilities are reported in other liabilities. In recognizing ROU assets and related lease liabilities, lease and non-lease components (such as taxes, insurance and common area maintenance costs) are accounted for separately as such amounts are generally readily determinable under the Company's lease contracts. Lease expense is recognized on a straight-line basis over the lease term and is recorded within occupancy and equipment expense in the Consolidated Statements of Income. Variable lease payments, which generally relate to the non-lease components noted above, are expensed as incurred. The following tables provide the components of lease cost and supplemental information: Three Months Ended (in millions) 2020 2019 Operating lease cost $ 16.7 $ 15.3 Variable lease cost 3.1 2.3 Finance lease cost 0.1 — Sublease income (0.5) (0.4) Net lease cost $ 19.4 $ 17.2 (dollars in millions) March 31, 2020 December 31, 2019 Lease ROU assets: Operating leases $ 275.9 $ 276.6 Finance leases 2.5 2.6 Lease liabilities: Operating leases 307.5 307.9 Finance leases 5.2 5.3 Weighted-average discount rate: Operating leases 3.12 % 3.13 % Finance leases 2.58 2.58 Weighted-average remaining lease term (in years): Operating leases 7.8 7.7 Finance leases 11.9 12.2 Three Months Ended (in millions) 2020 2019 Cash payments included in the measurement of lease liabilities: Reported in operating cash from operating leases $ 17.1 $ 15.4 Reported in financing cash from finance leases 0.1 — ROU assets obtained in exchange for lessee: Operating lease liabilities (1) 14.3 10.3 Finance lease liabilities (1) — — (1) Excludes related transition adjustment recorded during three months ended March 31, 2019 ( see above ). The contractual maturities of the Company's lease liabilities as of March 31, 2020 were as follows: (in millions) Operating Leases Finance Leases 2020 (1) $ 50.4 $ 0.4 2021 65.3 0.5 2022 47.7 0.5 2023 36.0 0.5 2024 30.0 0.5 Later years 121.0 3.7 Total lease payments 350.4 6.1 Less: Interest (42.9) (0.9) Total lease liabilities $ 307.5 $ 5.2 (1) Contractual maturities for the nine months remaining in 2020.
Leases	NOTE 5. LEASES Effective January 1, 2019, People's United adopted new accounting guidance relating to real estate (primarily branch locations) and office equipment subject to non-cancelable operating lease agreements entered into by the Company as lessee. The amount of the right-of-use ("ROU") assets and corresponding lease liabilities recorded upon adoption were based, primarily, on the present value of unpaid future minimum lease payments, the amount of which is dependent upon the population of leases in effect at the date of adoption, as well as assumptions with respect to renewals and/or extensions and the interest rate used to discount the future lease obligations. As it relates to lease agreements entered into with equipment financing customers, and for which the Company acts as lessor, the impact principally relates to the definition of eligible initial direct costs ("IDC") under the new guidance. Specifically, the standard maintains a narrower definition of IDC which will result in the Company recognizing immediately (rather than deferring) certain lease origination-related expenses. Such expenses would be offset by the recognition of a higher yield on the underlying leases over their contractual term. Upon adoption, the Company recognized (i) operating lease liabilities totaling $268.8 million, based on the present value of the remaining minimum lease payments, determined using a discount rate as of the effective date and (ii) corresponding ROU assets totaling $248.5 million, based upon the operating lease liabilities, adjusted for prepaid and deferred rent, and liabilities associated with lease termination costs. Lessor Arrangements People's United provides equipment financing to its customers through a variety of lessor arrangements, some of which may include options to renew and/or for the lessee to purchase the leased equipment at the end of the lease term. Direct financing leases and sales-type leases (collectively, "lease financing receivables") are carried at the aggregate of lease payments receivable plus the estimated residual value of the leased assets and any initial direct costs incurred to originate these leases , less unearned income, which is accreted to interest income over the lease term using the interest method. The residual value component of a lease financing receivable represents the estimated fair value of the leased equipment at the end of the lease term. In establishing residual value estimates, the Company may rely on industry data, historical experience, independent appraisals and, where appropriate, information regarding product life cycle, product upgrades and competing products. Upon expiration of a lease, residual assets are remarketed, resulting in an extension of the lease by the lessee, a lease to a new customer or purchase of the residual asset by the lessee or another party. Impairment of residual values arises if the expected fair value is less than the carrying amount. The Company assesses its net investment in lease financing receivables (including residual values) for impairment on a quarterly basis with any impairment losses recognized in accordance with the impairment guidance for financial instruments. As such, net investment in lease financing receivables may be reduced by an ACL with changes recognized as provision expense. The composition of the Company’s total net investment in lease financing receivables included within equipment financing loans in the Consolidated Statements of Condition was as follows: (in millions) March 31, 2020 December 31, 2019 Lease payments receivable $ 1,451.7 $ 1,417.1 Estimated residual value of leased assets 128.7 128.0 Gross investment in lease financing receivables 1,580.4 1,545.1 Plus: Deferred origination costs 13.0 13.4 Less: Unearned income (158.5) (156.9) Total net investment in lease financing receivables $ 1,434.9 $ 1,401.6 The contractual maturities of the Company's lease financing receivables were as follows: (in millions) March 31, 2020 2020 (1) $ 408.6 2021 448.4 2022 340.8 2023 208.7 2024 117.7 Later years 56.2 Total $ 1,580.4 (1) Contractual maturities for the nine months remaining in 2020. Operating lease income, generated in connection with operating leases for which the Company acts as a lessor, is recognized on a straight-line basis over the lease term as a component of non-interest income in the Consolidated Statements of Income. Depreciation expense for assets under operating leases, which are included in other assets in the Consolidated Statements of Condition, is generally recorded on a straight-line basis over the lease term as a component of non-interest expense in the Consolidated Statements of Income. The following table summarizes People's United's total lease income: Three Months Ended (in millions) 2020 2019 Lease financing receivables $ 17.6 $ 15.5 Operating leases 12.6 12.7 Total lease income $ 30.2 $ 28.2 Lessee Arrangements Substantially all of the Company’s lessee arrangements represent non-cancelable operating leases for real estate (primarily branch locations) and office equipment with terms extending through 2054. Under these arrangements, People's United records ROU assets and corresponding lease liabilities at lease commencement. Lease liabilities are recognized based on the present value of the remaining lease payments and discounted using the Company’s incremental borrowing rate for borrowings of similar term. ROU assets initially equal the related lease liability, adjusted for any lease payments made prior to the lease commencement and any lease incentives. Portions of certain properties are subleased for terms extending through 2028. At lease commencement, the Company considers renewal or termination options in the determination of the term of the lease. If it is reasonably certain that a renewal or termination option will be exercised, the effects of such options are included in the determination of the expected lease term. All leases are recorded with the exception of leases with an initial term of twelve months or less for which the Company made the short-term lease election. Within the Consolidated Statements of Condition, ROU assets are reported in other assets and the related lease liabilities are reported in other liabilities. In recognizing ROU assets and related lease liabilities, lease and non-lease components (such as taxes, insurance and common area maintenance costs) are accounted for separately as such amounts are generally readily determinable under the Company's lease contracts. Lease expense is recognized on a straight-line basis over the lease term and is recorded within occupancy and equipment expense in the Consolidated Statements of Income. Variable lease payments, which generally relate to the non-lease components noted above, are expensed as incurred. The following tables provide the components of lease cost and supplemental information: Three Months Ended (in millions) 2020 2019 Operating lease cost $ 16.7 $ 15.3 Variable lease cost 3.1 2.3 Finance lease cost 0.1 — Sublease income (0.5) (0.4) Net lease cost $ 19.4 $ 17.2 (dollars in millions) March 31, 2020 December 31, 2019 Lease ROU assets: Operating leases $ 275.9 $ 276.6 Finance leases 2.5 2.6 Lease liabilities: Operating leases 307.5 307.9 Finance leases 5.2 5.3 Weighted-average discount rate: Operating leases 3.12 % 3.13 % Finance leases 2.58 2.58 Weighted-average remaining lease term (in years): Operating leases 7.8 7.7 Finance leases 11.9 12.2 Three Months Ended (in millions) 2020 2019 Cash payments included in the measurement of lease liabilities: Reported in operating cash from operating leases $ 17.1 $ 15.4 Reported in financing cash from finance leases 0.1 — ROU assets obtained in exchange for lessee: Operating lease liabilities (1) 14.3 10.3 Finance lease liabilities (1) — — (1) Excludes related transition adjustment recorded during three months ended March 31, 2019 ( see above ). The contractual maturities of the Company's lease liabilities as of March 31, 2020 were as follows: (in millions) Operating Leases Finance Leases 2020 (1) $ 50.4 $ 0.4 2021 65.3 0.5 2022 47.7 0.5 2023 36.0 0.5 2024 30.0 0.5 Later years 121.0 3.7 Total lease payments 350.4 6.1 Less: Interest (42.9) (0.9) Total lease liabilities $ 307.5 $ 5.2 (1) Contractual maturities for the nine months remaining in 2020.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Stockholders' Equity	NOTE 6. STOCKHOLDERS' EQUITY Preferred Stock and Common Stock People’s United is authorized to issue (i) 50.0 million shares of preferred stock, par value of $0.01 per share, of which 10.0 million shares were outstanding at both March 31, 2020 and December 31, 2019, and (ii) 1.95 billion shares of common stock, par value of $0.01 per share, of which 533.5 million shares and 532.8 million shares were issued at March 31, 2020 and December 31, 2019, respectively. Treasury Stock Treasury stock includes (i) common stock repurchased by People’s United, either directly or through agents, in the open market at prices and terms satisfactory to management in connection with stock repurchases authorized by its Board of Directors (106.4 million shares and 86.6 million shares at March 31, 2020 and December 31, 2019, respectively) and (ii) common stock purchased in the open market by a trustee with funds provided by People’s United and originally intended for awards under the People’s United Financial, Inc. 2007 Recognition and Retention Plan (the “RRP”) (2.6 million shares at both March 31, 2020 and December 31, 2019). Following shareholder approval of the People’s United Financial, Inc. 2014 Long-Term Incentive Plan in 2014, no new awards may be granted under the RRP. In June 2019, the Company’s Board of Directors authorized the repurchase of up to 20.0 million shares of People’s United’s outstanding common stock. Such shares may be repurchased, either directly or through agents, in the open market at prices and terms satisfactory to management. During the first quarter of 2020, the Company completed the repurchase authorization by purchasing 19.8 million shares of People's United common stock at a total cost of $304.4 million. Comprehensive Income Comprehensive income represents the sum of net income and items of “other comprehensive income or loss,” including (on an after-tax basis): (i) net actuarial gains and losses, prior service credits and costs, and transition assets and obligations related to People’s United’s pension and other postretirement plans; (ii) net unrealized gains and losses on debt securities available-for-sale; (iii) net unrealized gains and losses on debt securities transferred to held-to-maturity; and (iv) net unrealized gains and losses on derivatives accounted for as cash flow hedges. People’s United’s total comprehensive income for the three months ended March 31, 2020 and 2019 is reported in the Consolidated Statements of Comprehensive Income. The following is a summary of the changes in the components of accumulated other comprehensive income loss ("AOCL"), which are included in People’s United’s stockholders’ equity on an after-tax basis: (in millions) Pension and Other Postretirement Plans Net Unrealized Gains (Losses) on Debt Securities Available-for-Sale Net Unrealized Gains (Losses) on Debt Securities Transferred to Held-to-Maturity Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges Total AOCL Balance at December 31, 2019 $ (176.2) $ 20.8 $ (11.8) $ 0.3 $ (166.9) Other comprehensive income — 71.6 — — 71.6 Amounts reclassified from AOCL (1) 1.6 — 1.0 — 2.6 Current period other comprehensive 1.6 71.6 1.0 — 74.2 Balance at March 31, 2020 $ (174.6) $ 92.4 $ (10.8) $ 0.3 $ (92.7) (in millions) Pension and Other Postretirement Plans Net Unrealized Gains (Losses) on Debt Securities Available-for-Sale Net Unrealized Gains (Losses) on Debt Securities Transferred to Held-to-Maturity Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges Total AOCL Balance at December 31, 2018 $ (192.5) $ (47.0) $ (15.3) $ (2.0) $ (256.8) Other comprehensive income before — 29.0 — 0.5 29.5 Amounts reclassified from AOCL (1) 1.8 — 0.6 0.3 2.7 Current period other comprehensive 1.8 29.0 0.6 0.8 32.2 Balance at March 31, 2019 $ (190.7) $ (18.0) $ (14.7) $ (1.2) $ (224.6) (1) See the following table for details about these reclassifications. The following is a summary of the amounts reclassified from AOCL: Amounts Reclassified from AOCL Affected Line Item in the Statement Where Net Income is Presented Three Months Ended (in millions) 2020 2019 Details about components of AOCL: Amortization of pension and other Net actuarial loss $ (2.0) $ (1.3) (1) (2.0) (1.3) Income before income tax expense 0.4 (0.5) Income tax expense (1.6) (1.8) Net income Reclassification adjustment for net — — Income before income tax expense (2) — — Income tax expense — — Net income Amortization of unrealized losses on (1.3) (0.8) Income before income tax expense (3) 0.3 0.2 Income tax expense (1.0) (0.6) Net income Amortization of unrealized gains and Interest rate swaps — (0.4) (5) Interest rate locks (4) — — (5) — (0.4) Income before income tax expense — 0.1 Income tax expense — (0.3) Net income Total reclassifications for the period $ (2.6) $ (2.7) (1) Included in the computation of net periodic benefit income (expense) reflected in other non-interest expense (see Note 9 for additional details). (2) Included in other non-interest income. (3) Included in interest and dividend income - securities. (4) Amount reclassified from AOCL totaled less than $0.1 million for both periods (5) Included in interest expense - notes and debentures.

Earnings Per Common Share

Earnings Per Common Share	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Common Share	NOTE 7. EARNINGS PER COMMON SHARE The following is an analysis of People’s United’s basic and diluted earnings per common share (“EPS”), reflecting the application of the two-class method, as described below: Three Months Ended (in millions, except per common share data) 2020 2019 Net income available to common shareholders $ 126.9 $ 111.1 Dividends paid on and undistributed earnings allocated to — — Earnings attributable to common shareholders $ 126.9 $ 111.1 Weighted average common shares outstanding for basic EPS 427.2 370.7 Effect of dilutive equity-based awards 2.6 3.4 Weighted average common shares and common-equivalent 429.8 374.1 EPS: Basic $ 0.30 $ 0.30 Diluted 0.30 0.30 Unvested share-based payment awards, which include the right to receive non-forfeitable dividends or dividend equivalents, are considered to participate with common stock in undistributed earnings for purposes of computing EPS. Companies that have such participating securities, including People’s United, are required to calculate basic and diluted EPS using the two-class method. Restricted stock awards granted by People’s United prior to 2017 are considered participating securities. Calculations of EPS under the two-class method (i) exclude from the numerator any dividends paid or owed on participating securities and any undistributed earnings considered to be attributable to participating securities and (ii) exclude from the denominator the dilutive impact of the participating securities. All unallocated ESOP common shares and all common shares accounted for as treasury shares have been excluded from the calculation of basic and diluted EPS. Anti-dilutive equity-based awards totaling 12.9 million shares and 7.2 million shares for the three months ended March 31, 2020 and 2019, respectively, have also been excluded from the calculation of diluted EPS.

Goodwill and Other Acquisition-

Goodwill and Other Acquisition-Related Intangible Assets	3 Months Ended
	Mar. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Acquisition-Related Intangible Assets	NOTE 8. GOODWILL AND OTHER ACQUISITION-RELATED INTANGIBLE ASSETS People’s United goodwill totaled $3.07 billion at both March 31, 2020 and December 31, 2019, and was allocated to its operating segments as follows: Commercial Banking ($1.97 billion); Retail Banking ($1.01 billion); and Wealth Management ($88.5 million). Recent acquisitions have been undertaken with the objective of expanding the Company’s business, both geographically and through product offerings, as well as realizing synergies and economies of scale by combining with the acquired entities. For these reasons, a market-based premium was paid for the acquired entities which, in turn, resulted in the recognition of goodwill, representing the excess of the respective purchase prices over the estimated fair value of the net assets acquired. All of People’s United’s tax deductible goodwill was created in transactions in which the Company purchased the assets of the target (as opposed to purchasing the issued and outstanding stock of the target). At March 31, 2020 and December 31, 2019 , tax deductible goo dwill totaled $131.8 million and $134.4 million, respectively. People’s United’s other acquisition-related intangible assets totaled $198.5 million and $209.1 million at March 31, 2020 and December 31, 2019, respectively. At March 31, 2020, the carrying amounts of other acquisition-related intangible assets were as follows: core deposit intangible ($118.9 million); trade name intangible ($49.0 million); client relationships intangible ($17.4 million); trust relationships intangible ($7.0 million); insurance relationships intangible ($3.7 million); favorable lease agreements ($2.3 million); and non-compete agreements ($0.2 million).

Employee Benefit Plans

Employee Benefit Plans	3 Months Ended
	Mar. 31, 2020
Retirement Benefits [Abstract]
Employee Benefit Plans	NOTE 9. EMPLOYEE BENEFIT PLANS People’s United Employee Pension and Other Postretirement Plans People’s United maintains a qualified noncontributory defined benefit pension plan (the “People’s Qualified Plan”) that covers substantially all full-time and part-time employees who (i) meet certain age and length of service requirements and (ii) were employed by the Bank prior to August 14, 2006. Benefits are based upon the employee’s years of credited service and either the average compensation for the last five years or the average compensation for the five New employees of the Bank starting on or after August 14, 2006 are not eligible to participate in the People’s Qualified Plan. Instead, the Bank makes contributions on behalf of these employees to a qualified defined contribution plan in an annual amount equal to 3% of the employee’s eligible compensation. Employee participation in this plan is restricted to employees who (i) are at least 18 years of age and (ii) worked at least 1,000 hours in a year. Both full-time and part-time employees are eligible to participate as long as they meet these requirements. In July 2011, the Bank amended the People’s Qualified Plan to “freeze”, effective December 31, 2011, the accrual of pension benefits for People’s Qualified Plan participants. As such, participants will not earn any additional benefits after that date. Instead, effective January 1, 2012, the Bank began making contributions on behalf of these participants to a qualified defined contribution plan in an annual amount equal to 3% of the employee’s eligible compensation. In addition to the People’s Qualified Plan, People’s United continues to maintain qualified defined benefit pension plans that cover (i) former First Connecticut Bancorp, Inc. employees who meet certain eligibility requirements (the “First Connecticut Qualified Plan”) and (ii) former United Financial Bancorp, Inc. employees who meet certain eligibility requirements (the “United Financial Qualified Plan”). All benefits under these plans were frozen effective February 28, 2013 and December 31, 2012, respectively. People’s United’s funding policy is to contribute the amounts required by applicable regulations, although additional amounts may be contributed from time to time. People’s United also maintains (i) unfunded, nonqualified supplemental plans to provide retirement benefits to certain senior officers (the “People’s Supplemental Plans”) and (ii) an unfunded plan that provides retirees with optional medical, dental and life insurance benefits (the “People’s Postretirement Plan”). People’s United accrues the cost of these postretirement benefits over the employees’ years of service to the date of their eligibility for such benefit. People’s United also continues to maintain: (1) for certain eligible former First Connecticut Bancorp, Inc. employees (i) an unfunded, nonqualified supplemental retirement plan (the “First Connecticut Supplemental Plan”) and (ii) unfunded plans that provide medical, dental and life insurance benefits (the “First Connecticut Postretirement Plans”); (2) for certain eligible former BSB Bancorp, Inc. employees (i) an unfunded, nonqualified supplemental retirement plan (the “BSB Bancorp Supplemental Plan”) and (ii) unfunded plans that provide life insurance benefits (the “BSB Bancorp Post Retirement Welfare (Life Insurance) Plan”); and (3) for certain former United Financial Bancorp, Inc. employees (i) an unfunded, nonqualified supplemental retirement plan (the “United Financial Supplemental Plan”) and (ii) unfunded plans that provide medical, dental and life insurance benefits (the “United Financial Postretirement Benefit Plan”). Components of net periodic benefit (income) expense and other amounts recognized in other comprehensive income (loss) for (i) the People’s Qualified Plan, the First Connecticut Qualified Plan, the People's Supplemental Plans, the First Connecticut Supplemental Plan, the BSB Bancorp Supplemental Plan and the United Financial Supplemental Plan (together the “Pension Plans”) and (ii) the People’s Postretirement Plan, the First Connecticut Postretirement Plans, the BSB Bancorp Post Retirement Welfare (Life Insurance) Plan and the United Financial Postretirement Plan (together the "Other Postretirement Plans") are as follows: Pension Plans Other Postretirement Plans Three months ended March 31 (in millions) 2020 2019 2020 2019 Net periodic benefit (income) expense: Interest cost $ 4.9 $ 5.6 $ 0.3 $ 0.3 Expected return on plan assets (12.4) (11.4) — — Recognized net actuarial loss 2.0 1.3 — — Settlements 0.8 0.6 — — Net periodic benefit (income) expense (1) (4.7) (3.9) 0.3 0.3 Other changes in plan assets and benefit obligations Net actuarial loss (2.0) (1.3) — — Prior service credit — — — — Total pre-tax changes recognized in other (2.0) (1.3) — — Total recognized in net periodic benefit (income) $ (6.7) $ (5.2) $ 0.3 $ 0.3 Employee Stock Ownership Plan In April 2007, People’s United established an ESOP. At that time, People’s United loaned the ESOP $216.8 million to purchase 10,453,575 shares of People’s United common stock in the open market. In order for the ESOP to repay the loan, People’s United expects to make annual cash contributions of approximately $18.8 million until 2036. Such cash contributions may be reduced by the cash dividends paid on unallocated ESOP shares, which, for the three months ended March 31, 2020, totaled $1.1 million. At March 31, 2020, the loan balance totaled $171.8 million. Employee participation in this plan is restricted to those employees who (i) are at least 18 years of age and (ii) worked at least 1,000 hours within 12 months of their hire date or any plan year (January 1 to December 31) after their date of hire. Employees meeting the aforementioned eligibility criteria during the plan year must continue to be employed as of the last day of the plan year in order to receive an allocation of shares for that plan year. Shares of People’s United common stock are held by the ESOP and allocated to eligible participants annually based upon a percentage of each participant’s eligible compensation. Since the ESOP was established, a total of 4,616,996 shares of People’s United common stock have been allocated or committed to be released to participants’ accounts. At March 31, 2020, 5,836,579 shares of People’s United common stock, with a fair value of $64.5 million at that date, have not been allocated or committed to be released. Compensation expense related to the ESOP is recognized at an amount equal to the number of common shares committed to be released by the ESOP for allocation to participants’ accounts multiplied by the average fair value of People’s United’s common stock during the reporting period. The difference between the fair value of the shares of People’s United’s common stock committed to be released and the cost of those common shares is recorded as a credit to additional paid-in capital (if fair value exceeds cost) or, to the extent that no such credits remain in additional paid-in capital, as a charge to retained earnings (if fair value is less than cost). Expense recognized for the ESOP totaled $1.2 million and $1.4 million for the three months ended March 31, 2020 and 2019, respectively.

Legal Proceedings

Legal Proceedings	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Legal Proceedings	NOTE 10. LEGAL PROCEEDINGS In the normal course of business, People’s United is subject to various legal proceedings. Management has discussed with legal counsel the nature of these legal proceedings and, based on the advice of counsel and the information currently available, believes that the eventual outcome of these legal proceedings will not have a material adverse effect on People’s United’s financial condition, results of operations or liquidity.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Segment Information	NOTE 11. SEGMENT INFORMATION See “Segment Results” included in Item 2 for segment information for the three months ended March 31, 2020 and 2019.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE 12. FAIR VALUE MEASUREMENTS Accounting standards related to fair value measurements define fair value, provide a framework for measuring fair value and establish related disclosure requirements. Broadly, fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. Accordingly, an “exit price” approach is required in determining fair value. In support of this principle, a fair value hierarchy has been established that prioritizes the inputs used to measure fair value, requiring entities to maximize the use of market or observable inputs (as more reliable measures) and minimize the use of unobservable inputs. Observable inputs reflect market data obtained from independent sources, while unobservable inputs generally require significant management judgment. The three levels within the fair value hierarchy are as follows: • Level 1 – Unadjusted quoted market prices for identical assets or liabilities in active markets that the entity has the ability to access at the measurement date (such as active exchange-traded equity securities or mutual funds and certain U.S. and government agency debt securities). • Level 2 – Observable inputs other than quoted prices included in Level 1, such as: ▪ quoted prices for similar assets or liabilities in active markets (such as U.S. agency and GSE issued mortgage-backed and CMO securities); ▪ quoted prices for identical or similar assets or liabilities in less active markets (such as certain U.S. and government agency debt securities, and corporate and municipal debt securities that trade infrequently); and ▪ other inputs that (i) are observable for substantially the full term of the asset or liability (e.g. interest rates, yield curves, prepayment speeds, default rates, etc.) or (ii) can be corroborated by observable market data (such as interest rate and currency derivatives and certain other securities). • Level 3 – Valuation techniques that require unobservable inputs that are supported by little or no market activity and are significant to the fair value measurement of the asset or liability (such as pricing models, discounted cash flow methodologies and similar techniques that typically reflect management’s own estimates of the assumptions a market participant would use in pricing the asset or liability). People’s United maintains policies and procedures to value assets and liabilities using the most relevant data available. Described below are the valuation methodologies used by People’s United and the resulting fair values for those financial instruments measured at fair value on both a recurring and a non-recurring basis. For those financial instruments not measured at fair value either on a recurring or non-recurring basis, disclosure of each instrument’s carrying amount and estimated fair value has been provided. Recurring Fair Value Measurements Trading Debt Securities, Equity Securities and Debt Securities Available-For-Sale When available, People’s United uses quoted market prices for identical securities received from an independent, nationally-recognized, third-party pricing service (as discussed further below) to determine the fair value of investment securities such as U.S. Treasury and agency securities and equity securities that are included in Level 1. When quoted market prices for identical securities are unavailable, People’s United uses prices provided by the independent pricing service based on recent trading activity and other observable information including, but not limited to, market interest rate curves, referenced credit spreads and estimated prepayment rates where applicable. These investments include certain U.S. and government agency debt securities, corporate and municipal debt securities, and GSE mortgage-backed and CMO securities, all of which are included in Level 2. The Company’s available-for-sale debt securities are primarily comprised of GSE mortgage-backed securities. The fair value of these securities is based on prices obtained from the independent pricing service. The pricing service uses various techniques to determine pricing for the Company’s mortgage-backed securities, including option pricing and discounted cash flow analysis. The inputs include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, benchmark securities, bids, offers, reference data, monthly payment information and collateral performance. At both March 31, 2020 and December 31, 2019, the entire available-for-sale mortgage-backed securities portfolio was comprised of GSE mortgage-backed and CMO securities with original final maturities ranging from 10 to 40 years. An active market exists for securities that are similar to the Company’s GSE mortgage-backed and CMO securities, making observable inputs readily available. Changes in the prices obtained from the pricing service are analyzed from month to month, taking into consideration changes in market conditions including changes in mortgage spreads, changes in U.S. Treasury security yields and changes in generic pricing of securities with similar duration. As a further point of validation, the Company generates its own month-end fair value estimate for all mortgage-backed securities, and state and municipal securities. While the Company has not adjusted the prices obtained from the independent pricing service, any notable differences between those prices and the Company’s estimates are subject to further analysis. This additional analysis may include a review of prices provided by other independent parties, a yield analysis, a review of average life changes using Bloomberg analytics and a review of historical pricing for the particular security. Based on management’s review of the prices provided by the pricing service, the fair values incorporate observable market inputs used by market participants at the measurement date and, as such, are classified as Level 2 securities. Other Assets As discussed in Note 9, certain unfunded, nonqualified supplemental plans have been established to provide retirement benefits to certain senior officers. People’s United has funded two trusts to provide benefit payments to the extent such benefits are not paid directly by People’s United, the assets of which are included in other assets in the Consolidated Statements of Condition. When available, People’s United determines the fair value of the trust assets using quoted market prices for identical securities received from a third-party nationally recognized pricing service. Derivatives People’s United values its derivatives using internal models that are based on market or observable inputs including interest rate curves and forward/spot prices for selected currencies. Derivative assets and liabilities included in Level 2 represent interest rate swaps and caps, foreign exchange contracts, risk participation agreements, forward commitments to sell residential mortgage loans and interest rate-lock commitments on residential mortgage loans. The following tables summarize People’s United’s financial instruments that are measured at fair value on a recurring basis: Fair Value Measurements Using As of March 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Debt securities available-for-sale: U.S. Treasury and agency $ 747.2 $ — $ — $ 747.2 GSE mortgage-backed and CMO securities — 3,529.4 — 3,529.4 Equity securities 6.2 — — 6.2 Other assets: Exchange-traded funds 39.8 — — 39.8 Mutual funds 2.9 — — 2.9 Interest rate swaps — 932.9 — 932.9 Interest rate caps — 3.6 — 3.6 Foreign exchange contracts — 8.6 — 8.6 Forward commitments to sell residential mortgage loans — 0.6 — 0.6 Total $ 796.1 $ 4,475.1 $ — $ 5,271.2 Financial liabilities: Interest rate swaps $ — $ 184.5 $ — $ 184.5 Interest rate caps — 3.6 — 3.6 Risk participation agreements — 0.5 — 0.5 Foreign exchange contracts — 9.2 — 9.2 Interest rate-lock commitments on residential mortgage loans — 0.7 — 0.7 Total $ — $ 198.5 $ — $ 198.5 Fair Value Measurements Using As of December 31, 2019 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Trading debt securities: U.S. Treasury $ 7.1 $ — $ — $ 7.1 Debt securities available-for-sale: U.S. Treasury and agency 687.1 — — 687.1 GSE mortgage-backed and CMO securities — 2,877.2 — 2,877.2 Equity securities 8.2 — — 8.2 Other assets: Exchange-traded funds 47.7 — — 47.7 Mutual funds 3.3 — — 3.3 Fixed income securities — — — — Interest rate swaps — 337.6 — 337.6 Interest rate caps — 1.7 — 1.7 Foreign exchange contracts — 1.2 — 1.2 Forward commitments to sell residential mortgage loans — 0.5 — 0.5 Total $ 753.4 $ 3,218.2 $ — $ 3,971.6 Financial liabilities: Interest rate swaps $ — $ 92.1 $ — $ 92.1 Interest rate caps — 1.7 — 1.7 Risk participation agreements — 0.1 — 0.1 Foreign exchange contracts — 1.8 — 1.8 Interest rate-lock commitments on residential mortgage loans — 0.5 — 0.5 Total $ — $ 96.2 $ — $ 96.2 Non-Recurring Fair Value Measurements Loans Held-for-Sale Loans held-for-sale are recorded at the lower of amortized cost or fair value and are therefore measured at fair value on a non-recurring basis. When available, People’s United uses observable secondary market data, including pricing on recent closed market transactions for loans with similar characteristics. Accordingly, such loans are classified as Level 2 measurements. When observable data is unavailable, valuation methodologies using current market interest rate data adjusted for inherent credit risk are used, and such loans are included in Level 3. REO and Repossessed Assets REO and repossessed assets are recorded at the lower of cost or fair value, less estimated selling costs, and are therefore measured at fair value on a non-recurring basis. People’s United has estimated the fair values of these assets using Level 3 inputs, such as independent third-party appraisals and price opinions. Such appraisals are based on the market and/or income approach to value and are subject to a discount (to reflect estimated cost to sell) that generally approximates 10%. Assets that are acquired through loan default are recorded as held-for-sale initially at the lower of the recorded investment in the loan or fair value (less estimated selling costs) upon the date of foreclosure/repossession. Subsequent to foreclosure/repossession, valuations are updated periodically and the carrying amounts of these assets may be reduced further. Mortgage Servicing Rights Mortgage servicing rights are evaluated for impairment based upon the fair value of the servicing rights as compared to their amortized cost. The fair value of mortgage servicing rights is based on a valuation model that calculates the present value of estimated net servicing income. This model incorporates certain assumptions that market participants would likely use in estimating future net servicing income, such as interest rates, prepayment speeds and the cost to service (including delinquency and foreclosure costs), all of which require a degree of management judgment. Adjustments are only recorded when the discounted cash flows derived from the valuation model are less than the carrying value of the asset. As such, mortgage servicing rights are subject to measurement at fair value on a non-recurring basis and are classified as Level 3 assets. Collateral Dependent / Impaired Loans (periods prior to January 1, 2020) The Company’s approach to determining the fair value of collateral dependent loans is described in Note 3, “Loans”. At March 31, 2020, collateral dependent loans with an amortized cost of $15.2 million had a corresponding ACL (determined using a Level 3 measurement approach) of $8.9 million. The provision for credit losses associated with collateral dependent loans totaled $3.9 million for the three months ended March 31, 2020. Prior to the Company's adoption of the CECL standard, loan impairment was deemed to exist when full repayment of principal and interest according to the contractual terms of the loan was no longer probable. Impaired loans were reported based on one of three measures: (i) the present value of expected future cash flows discounted at the loan’s original effective interest rate; (ii) the loan’s observable market price; or (iii) the fair value of the collateral (less estimated cost to sell) if the loan is collateral dependent. Accordingly, certain impaired loans may have been subject to measurement at fair value on a non-recurring basis. People’s United has estimated the fair values of these assets using Level 3 inputs, such as discounted cash flows based on inputs that are largely unobservable and, instead, reflect management’s own estimates of the assumptions a market participant would use in pricing such loans and/or the fair value of collateral based on independent third-party appraisals for collateral dependent loans. Such appraisals are based on the market and/or income approach to value and are subject to a discount (to reflect estimated cost to sell) that generally approximates 10%. The following tables summarize People’s United’s assets that are measured at fair value on a non-recurring basis: Fair Value Measurements Using As of March 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Loans held-for-sale (1) $ — $ 19.2 $ — $ 19.2 REO and repossessed assets (2) — — 21.4 21.4 Mortgage servicing rights (3) — — 7.7 7.7 Total $ — $ 19.2 $ 29.1 $ 48.3 Fair Value Measurements Using As of December 31, 2019 (in millions) Level 1 Level 2 Level 3 Total Loans held-for-sale: Commercial $ — $ — $ 157.9 $ 157.9 Other consumer — — 333.7 333.7 Residential (1) — 19.7 — 19.7 Impaired loans (4) — — 61.9 61.9 REO and repossessed assets (2) — — 23.4 23.4 Mortgage servicing rights — — 10.3 10.3 Total $ — $ 19.7 $ 587.2 $ 606.9 (1) Consists of residential mortgage loans; no fair value adjustments were recorded for the three months ended March 31, 2020 and 2019. (2) Represents: (i) $9.5 million of residential REO; (ii) $7.3 million of commercial REO; and (iii) $4.6 million of repossessed assets at March 31, 2020. Charge-offs to the ACL related to loans that were transferred to REO or repossessed assets totaled $1.2 million and $0.3 million for the three months ended March 31, 2020 and 2019, respectively. Write downs and net (gains) loss on sale of foreclosed/repossessed assets charged to non-interest expense totaled $0.4 million and $0.1 million for the same periods. (3) A fair value adjustment totaling $3.0 million was recorded for the three months ended March 31, 2020. (4) Represents the recorded investment in impaired loans with a related ACL measured in accordance with applicable accounting guidance. The provision for credit losses on impaired loans totaled $0.6 million for the three months ended March 31, 2019. Financial Assets and Financial Liabilities Not Measured At Fair Value The following tables summarize the carrying amounts, estimated fair values and placement in the fair value hierarchy of People’s United’s financial instruments that are not measured at fair value either on a recurring or non-recurring basis: Carrying Amount Estimated Fair Value Measurements Using As of March 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Cash and due from banks $ 507.6 $ 507.6 $ — $ — $ 507.6 Short-term investments 744.3 — 744.3 — 744.3 Debt securities held-to-maturity, net 3,861.5 — 4,063.7 1.5 4,065.2 FHLB and FRB stock 407.2 — 407.2 — 407.2 Total loans, net (1) 43,927.1 — 9,999.3 34,597.9 44,597.2 Financial liabilities: Time deposits 8,840.2 — 8,891.5 — 8,891.5 Other deposits 35,900.9 — 35,900.9 — 35,900.9 FHLB advances 4,489.7 — 4,490.7 — 4,490.7 Federal funds purchased 1,120.0 — 1,120.0 — 1,120.0 Customer repurchase agreements 301.1 — 301.1 — 301.1 Notes and debentures 1,012.6 — 995.8 — 995.8 Carrying Amount Estimated Fair Value Measurements Using As of December 31, 2019 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Cash and due from banks $ 484.2 $ 484.2 $ — $ — $ 484.2 Short-term investments 316.8 — 316.8 — 316.8 Debt securities held-to-maturity 3,869.2 — 4,018.5 1.5 4,020.0 FHLB and FRB stock 341.1 — 341.1 — 341.1 Total loans, net (1) 43,287.6 — 10,072.1 33,282.9 43,355.0 Financial liabilities: Time deposits 9,205.5 — 9,218.1 — 9,218.1 Other deposits 34,384.0 — 34,384.0 — 34,384.0 FHLB advances 3,125.4 — 3,125.5 — 3,125.5 Federal funds purchased 1,620.0 — 1,620.0 — 1,620.0 Customer repurchase agreements 409.1 — 409.1 — 409.1 Other borrowings — 11.0 — 11.0 Notes and debentures 993.1 — 1,021.3 — 1,021.3 (1) Excludes collateral dependent loans totaling $15.2 million at March 31, 2020 and impaired loans totaling $61.9 million measured at fair value on a non-recurring basis at December 31, 2019.

Derivative Financial Instrument

Derivative Financial Instruments and Hedging Activities	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments and Hedging Activities	NOTE 13. DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES People’s United uses derivative financial instruments as components of its market risk management (principally to manage interest rate risk (“IRR”)). Certain other derivatives are entered into in connection with transactions with commercial customers. Derivatives are not used for speculative purposes. All derivatives are recognized as either assets or liabilities in the Consolidated Statements of Condition, reported at fair value and presented on a gross basis. Until a derivative is settled, a favorable change in fair value results in an unrealized gain that is recognized as an asset, while an unfavorable change in fair value results in an unrealized loss that is recognized as a liability. The Company generally applies hedge accounting to its derivatives used for market risk management purposes. Hedge accounting is permitted only if specific criteria are met, including a requirement that a highly effective relationship exist between the derivative instrument and the hedged item, both at inception of the hedge and on an ongoing basis. The hedge accounting method depends upon whether the derivative instrument is classified as a fair value hedge (i.e. hedging an exposure related to a recognized asset or liability, or a firm commitment) or a cash flow hedge (i.e. hedging an exposure related to the variability of future cash flows associated with a recognized asset or liability, or a forecasted transaction). Changes in the fair value of effective fair value hedges are recognized in current earnings (with the change in fair value of the hedged asset or liability also recorded in earnings). Changes in the fair value of effective cash flow hedges are recognized in other comprehensive income (loss) until earnings are affected by the variability in cash flows of the designated hedged item. Ineffective portions of hedge results are recognized in current earnings. Changes in the fair value of derivatives for which hedge accounting is not applied are recognized in current earnings. People’s United formally documents at inception all relationships between the derivative instruments and the hedged items, as well as its risk management objectives and strategies for undertaking the hedge transactions. This process includes linking all derivatives that are designated as hedges to specific assets and liabilities, or to specific firm commitments or forecasted transactions. People’s United also formally assesses, both at inception of the hedge and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in the fair values or cash flows of the hedged items. If it is determined that a derivative is not highly effective or has ceased to be a highly effective hedge, People’s United would discontinue hedge accounting prospectively. Gains or losses resulting from the termination of a derivative accounted for as a cash flow hedge remain in AOCL and are amortized to earnings over the remaining period of the former hedging relationship, provided the hedged item continues to be outstanding or it is probable the forecasted transaction will occur. People’s United uses the dollar offset method, regression analysis and scenario analysis to assess hedge effectiveness at inception and on an ongoing basis. Such methods are chosen based on the nature of the hedge strategy and are used consistently throughout the life of the hedging relationship. Certain derivative financial instruments are offered to commercial customers to assist them in meeting their financing and investing objectives and for their risk management purposes. These derivative financial instruments consist primarily of interest rate swaps and caps, but also include foreign exchange contracts. The interest rate and foreign exchange risks associated with customer interest rate swaps and caps and foreign exchange contracts are mitigated by entering into similar derivatives having essentially offsetting terms with institutional counterparties. Interest rate-lock commitments extended to borrowers relate to the origination of residential mortgage loans. To mitigate the IRR inherent in these commitments, People’s United enters into mandatory delivery and best efforts contracts to sell adjustable-rate and fixed-rate residential mortgage loans (servicing released). Forward commitments to sell and interest rate-lock commitments on residential mortgage loans are considered derivatives and their respective estimated fair values are adjusted based on changes in interest rates. Changes in the fair value of derivatives for which hedge accounting is not applied are recognized in current earnings, including customer derivatives, interest-rate lock commitments and forward sale commitments. By using derivatives, People’s United is exposed to credit risk to the extent that counterparties to the derivative contracts do not perform as required. Should a counterparty fail to perform under the terms of a derivative contract, the Company’s counterparty credit risk is equal to the amount reported as a derivative asset in the Consolidated Statements of Condition. In accordance with the Company’s balance sheet offsetting policy (see Note 14), amounts reported as derivative assets represent derivative contracts in a gain position, without consideration for derivative contracts in a loss position with the same counterparty (to the extent subject to master netting arrangements) and posted collateral. People’s United seeks to minimize counterparty credit risk through credit approvals, limits, monitoring procedures, execution of master netting arrangements and obtaining collateral, where appropriate. Counterparties to People’s United’s derivatives include major financial institutions and exchanges that undergo comprehensive and periodic internal credit analysis as well as maintain investment grade credit ratings from the major credit rating agencies. As such, management believes the risk of incurring credit losses on derivative contracts with those counterparties is remote and losses, if any, would be immaterial. Certain of People’s United’s derivative contracts contain provisions establishing collateral requirements (subject to minimum collateral posting thresholds) based on the Company’s external credit rating. If the Company’s senior unsecured debt rating were to fall below the level generally recognized as investment grade, the counterparties to such derivative contracts could require additional collateral on those derivative transactions in a net liability position (after considering the effect of master netting arrangements and posted collateral). There were no derivative instruments with such credit-related contingent features that were in a net liability position at March 31, 2020. The following sections further discuss each class of derivative financial instrument used by People’s United, including management’s principal objectives and risk management strategies. Interest Rate Swaps People’s United may, from time to time, enter into interest rate swaps that are used to manage IRR associated with certain interest-earning assets and interest-bearing liabilities. The Bank has entered into pay floating/receive fixed interest rate swaps to reduce its IRR exposure to the variability in interest cash flows on certain floating-rate commercial loans. The Bank has agreed with the swap counterparties to exchange, at specified intervals, the difference between fixed-rate and floating-rate interest amounts calculated based on notional amounts totaling $210 million. The floating-rate interest payments made under the swaps are calculated using the same floating rate received on the commercial loans. The swaps effectively convert the floating-rate one-month LIBOR interest payments received on the commercial loans to a fixed rate and consequently reduce the Bank’s exposure to variability in short-term interest rates. These swaps are accounted for as cash flow hedges. The Bank has entered into a pay floating/receive fixed interest rate swap to hedge the change in fair value due to changes in interest rates of the Bank’s $400 million subordinated notes. The Bank has agreed with the swap counterparty to exchange, at specified intervals, the difference between fixed-rate and floating-rate interest amounts calculated based on a notional amount of $375 million. The fixed-rate interest payments received on the swap will essentially offset the fixed-rate interest payments made on these notes, notwithstanding the notional difference between these notes and the swap. The floating-rate interest amounts paid under the swap are calculated based on three-month LIBOR plus 126.5 basis points. The swap effectively converts the fixed-rate subordinated notes to a floating-rate liability. This swap is accounted for as a fair value hedge. The Bank has entered into two-year and three-year pay fixed/receive floating interest rate swaps to reduce its interest rate exposure by hedging the variability in interest cash flows on certain rolling three-month funding liabilities, which may consist of FHLB advances. The Bank has agreed with the swap counterparty to exchange, at specified intervals, the difference between fixed-rate and floating-rate interest amounts calculated based on an aggregate notional amount of $550 million. The interest rate swaps effectively convert a short-term benchmark interest rate (LIBOR) into a fixed-rate. These swaps are accounted for as cash flow hedges. Customer Derivatives People’s United enters into interest rate swaps and caps with certain of its commercial customers. In order to minimize its risk, these customer interest rate swaps (pay floating/receive fixed) and caps have been offset with essentially matching interest rate swaps (pay fixed/receive floating) and caps with People’s United’s institutional counterparties. Hedge accounting has not been applied for these derivatives. Accordingly, changes in the fair value of all such interest rate swaps and caps are recognized in current earnings. Foreign Exchange Contracts Foreign exchange contracts are commitments to buy or sell foreign currency on a future date at a contractual price. People’s United uses these instruments on a limited basis to (i) eliminate its exposure to fluctuations in currency exchange rates on certain of its commercial loans that are denominated in foreign currencies and (ii) provide foreign exchange contracts on behalf of commercial customers within credit exposure limits. Gains and losses on foreign exchange contracts substantially offset the translation gains and losses on the related loans. Risk Participation Agreements People’s United enters into risk participation agreements under which it may either assume or sell credit risk associated with a borrower’s performance under certain interest rate derivative contracts. In those instances in which People’s United has assumed credit risk, it is not a party to the derivative contract and has entered into the risk participation agreement because it is also a party to the related loan agreement with the borrower. In those instances in which People’s United has sold credit risk, it is a party to the derivative contract and has entered into the risk participation agreement because it sold a portion of the related loan. People’s United manages its credit risk under risk participation agreements by monitoring the creditworthiness of the borrower, based on its normal credit review process. The notional amounts of the risk participation agreements reflect People’s United’s pro-rata share of the derivative contracts, consistent with its share of the related loans. Forward Commitments to Sell Residential Mortgage Loans and Related Interest Rate-Lock Commitments People’s United enters into forward commitments to sell adjustable-rate and fixed-rate residential mortgage loans (all to be sold servicing released) in order to reduce the market risk associated with originating loans for sale in the secondary market. In order to fulfill a forward commitment, People’s United delivers originated loans at prices or yields specified by the contract. The risks associated with such contracts arise from the possible inability of counterparties to meet the contract terms or People’s United’s inability to originate the necessary loans. Gains and losses realized on the forward contracts are reported in the Consolidated Statements of Income as a component of the net gains on sales of residential mortgage loans. In the normal course of business, People’s United will commit to an interest rate on a mortgage loan application at the time of application, or anytime thereafter. The risks associated with these interest rate-lock commitments arise if market interest rates change prior to the closing of these loans. Both forward sales commitments and interest rate-lock commitments made to borrowers on held-for-sale loans are accounted for as derivatives, with changes in fair value recognized in current earnings. Interest Rate Locks In connection with its planned issuance of senior notes in the fourth quarter of 2012, People’s United entered into U.S. Treasury forward interest rate locks (“T-Locks”) to hedge the risk that the 10-year U.S. Treasury yield component of the underlying coupon of the fixed-rate senior notes would rise prior to establishing the fixed interest rate on the senior notes. Upon pricing the senior notes, the T-Locks were terminated and the unrealized gain of $0.9 million was included (on a net-of-tax basis) as a component of AOCL. The gain is being recognized as a reduction of interest expense over the ten-year period during which the hedged item ($500 million senior note issuance) affects earnings. The table below provides a summary of the notional amounts and fair values (presented on a gross basis) of derivatives outstanding: Fair Values (1) Notional Amounts Assets Liabilities (in millions) Type of Hedge March 31, Dec 31, March 31, Dec 31, 2019 March 31, Dec 31, 2019 Derivatives Not Designated as Hedging Interest rate swaps: Commercial customers N/A $ 9,207.6 $ 8,847.7 $ 905.4 $ 320.5 $ — $ 13.9 Institutional counterparties N/A 9,211.4 8,851.8 27.5 17.1 184.5 78.2 Interest rate caps: Commercial customers N/A 253.4 246.0 3.6 1.6 — 0.1 Institutional counterparties N/A 253.4 246.0 — 0.1 3.6 1.6 Risk participation agreements N/A 910.3 882.8 — — 0.5 0.1 Foreign exchange contracts N/A 237.7 180.4 8.6 1.2 9.2 1.8 Forward commitments to sell N/A 77.7 23.3 0.6 0.5 — — Interest rate-lock commitments on N/A 53.8 33.6 — — 0.7 0.5 Total 945.7 341.0 198.5 96.2 Derivatives Designated as Hedging Interest rate swaps: FHLB advances Cash flow 550.0 — — — — — Subordinated notes Fair value 375.0 375.0 — — — — Loans Cash flow 210.0 210.0 — — — — Total — — — — Total fair value of derivatives $ 945.7 $ 341.0 $ 198.5 $ 96.2 (1) Assets are recorded in other assets and liabilities are recorded in other liabilities. The following table summarizes the impact of People’s United’s derivatives on pre-tax income and AOCL: Type of Hedge Amount of Pre-Tax Gain (Loss) Recognized in Earnings (1) Amount of Pre-Tax Gain (Loss) Recognized in AOCL Three months ended March 31 (in millions) 2020 2019 2020 2019 Derivatives Not Designated as Hedging Interest rate swaps: Commercial customers N/A $ 613.6 $ 111.6 $ — $ — Institutional counterparties N/A (603.7) (108.8) — — Interest rate caps: Commercial customers N/A 2.0 1.1 — — Institutional counterparties N/A (2.0) (1.2) — — Foreign exchange contracts N/A 0.1 0.2 — — Risk participation agreements N/A (0.6) 0.1 — — Forward commitments to sell N/A 0.2 — — — Interest rate-lock commitments on N/A (0.2) — — — Total 9.4 3.0 — — Derivatives Designated as Hedging Interest rate swaps Fair value 0.4 (0.3) — — Interest rate swaps Cash flow — (0.4) 0.1 0.6 Interest rate locks (2) Cash flow — — — — Total 0.4 (0.7) 0.1 0.6 Total $ 9.8 $ 2.3 $ 0.1 $ 0.6 (1) Amounts recognized in earnings are recorded in interest income, interest expense or other non-interest income for derivatives designated as hedging instruments and in other non-interest income for derivatives not designated as hedging instruments. (2) Income totaled less than $0.1 million for both periods.

Balance Sheet Offsetting

Balance Sheet Offsetting	3 Months Ended
	Mar. 31, 2020
Offsetting [Abstract]
Balance Sheet Offsetting	NOTE 14. BALANCE SHEET OFFSETTING Assets and liabilities relating to certain financial instruments, including derivatives, may be eligible for offset in the Consolidated Statements of Condition and/or subject to enforceable master netting arrangements or similar agreements. People’s United’s derivative transactions with institutional counterparties are generally executed under International Swaps and Derivative Association (“ISDA”) master agreements, which include “right of set-off” provisions that provide for a single net settlement of all interest rate swap positions, as well as collateral, in the event of default on, or the termination of, any one contract. Nonetheless, the Company does not, except as indicated below, offset asset and liabilities under such arrangements in the Consolidated Statements of Condition. The Chicago Mercantile Exchange (“CME”) legally characterizes variation margin payments for over-the-counter derivatives that clear as settlements rather than collateral. Accordingly, the Company’s accounting policies classify, for accounting and presentation purposes, variation margin payments deemed to be legal settlements as a single unit of account with the related derivative(s). At both March 31, 2020 and December 31, 2019, this presentation impacted one of the Company’s institutional counterparties. As such, People’s United has, subject to the corresponding enforceable master netting arrangement, netted the institutional counterparty’s CME derivative position and offset the counterparty’s variation margin payments in the Consolidated Statement of Condition as of both dates. Collateral (generally in the form of marketable debt securities) pledged by counterparties in connection with derivative transactions is not reported in the Consolidated Statements of Condition unless the counterparty defaults. Collateral that has been pledged by People’s United to counterparties continues to be reported in the Consolidated Statements of Condition unless the Company defaults. The following tables provide a gross presentation, the effects of offsetting, and a net presentation of the Company’s financial instruments that are eligible for offset in the Consolidated Statements of Condition. The collateral amounts in these tables are limited to the outstanding balances of the related asset or liability (after netting is applied) and, therefore, instances of overcollateralization are not presented. In the tables below, the Net Amount Presented of the derivative assets and liabilities can be reconciled to the fair value of the Company’s derivative financial instruments in Note 13. The Company’s derivative contracts with commercial customers and customer repurchase agreements are not subject to master netting arrangements and, therefore, have been excluded from the tables below. Gross Amount Recognized Gross Amount Offset Net Amount Presented Gross Amounts Not Offset Financial Instruments Net Amount As of March 31, 2020 (in millions) Collateral Financial assets: Interest rate swaps: Counterparty A $ — $ — $ — $ — $ — $ — Counterparty B — — — — — — Counterparty C — — — — — — Counterparty D — — — — — — Counterparty E 27.5 — 27.5 — — 27.5 Other counterparties — — — — — — Foreign exchange contracts 8.6 — 8.6 — — 8.6 Total $ 36.1 $ — $ 36.1 $ — $ — $ 36.1 Financial liabilities: Interest rate swaps: Counterparty A $ 6.4 $ — $ 6.4 $ — $ (6.4) $ — Counterparty B 9.9 — 9.9 — (9.9) — Counterparty C 64.2 — 64.2 — (64.2) — Counterparty D 24.6 — 24.6 — (24.6) — Counterparty E — — — — — — Other counterparties 83.0 — 83.0 — (83.0) — Foreign exchange contracts 9.2 — 9.2 — — 9.2 Total $ 197.3 $ — $ 197.3 $ — $ (188.1) $ 9.2 Gross Amount Recognized Gross Amount Offset Net Amount Presented Gross Amounts Not Offset Financial Instruments Net Amount As of December 31, 2019 (in millions) Collateral Financial assets: Interest rate swaps: Counterparty A $ 0.2 $ — $ 0.2 $ (0.2) $ — $ — Counterparty B 0.1 — 0.1 (0.1) — — Counterparty C 0.4 — 0.4 (0.4) — — Counterparty D 0.1 — 0.1 (0.1) — — Counterparty E 15.3 — 15.3 — — 15.3 Other counterparties 1.1 — 1.1 (1.1) — — Foreign exchange contracts 1.2 — 1.2 — — 1.2 Total $ 18.4 $ — $ 18.4 $ (1.9) $ — $ 16.5 Financial liabilities: Interest rate swaps: Counterparty A $ 2.3 $ — $ 2.3 $ (0.2) $ (2.1) $ — Counterparty B 5.5 — 5.5 (0.1) (5.4) — Counterparty C 28.2 — 28.2 (0.4) (27.8) — Counterparty D 10.9 — 10.9 (0.1) (10.8) — Counterparty E — — — — — — Other counterparties 32.9 — 32.9 (1.1) (31.8) — Foreign exchange contracts 1.8 — 1.8 — — 1.8 Total $ 81.6 $ — $ 81.6 $ (1.9) $ (77.9) $ 1.8 Resale and repurchase agreements represent agreements to purchase/sell securities subject to an obligation to resell/repurchase the same or similar securities. People’s United accounts for securities resale agreements as secured lending transactions and securities repurchase agreements as secured borrowings since the transferor maintains effective control over the transferred securities and the transfer meets the other criteria for such accounting. The securities are pledged by the transferor as collateral and the transferee has the right by contract to repledge that collateral provided the same collateral is returned to the transferor upon maturity of the underlying agreement. The fair value of the pledged collateral approximates the recorded amount of the secured loan or borrowing. Decreases in the fair value of the transferred securities below an established threshold require the transferor to provide additional collateral. The following tables show the extent to which assets and liabilities exchanged under resale and repurchase agreements have been offset in the Consolidated Statements of Condition. These agreements: (i) are entered into simultaneously with the same financial institution counterparty; (ii) have the same principal amounts and inception/maturity dates; and (iii) are subject to a master netting arrangement that contains a conditional right of offset upon default. At March 31, 2020 and December 31, 2019, the Company posted as collateral marketable securities with fair values of $454.2 million and $462.4 million, respectively, and, in turn, accepted as collateral marketable securities with fair values of $464.0 million and $457.5 million, respectively. As of March 31, 2020 (in millions) Gross Amount Recognized Gross Amount Offset Net Amount Presented Total resale agreements $ 450.0 $ (450.0) $ — Total repurchase agreements $ 450.0 $ (450.0) $ — As of December 31, 2019 (in millions) Gross Amount Recognized Gross Amount Offset Net Amount Presented Total resale agreements $ 450.0 $ (450.0) $ — Total repurchase agreements $ 450.0 $ (450.0) $ —

New Accounting Standards

New Accounting Standards	3 Months Ended
	Mar. 31, 2020
Accounting Changes and Error Corrections [Abstract]
New Accounting Standards	NOTE 15. NEW ACCOUNTING STANDARDS Standards effective in 2020 Financial Instruments – Credit Losses In June 2016, the FASB amended its standards with respect to certain aspects of measurement, recognition and disclosure of credit losses on loans and other financial instruments carried at amortized cost, as well as available-for-sale debt securities and purchased financial assets with credit deterioration (“PCD assets”). The amendment is to be applied through a cumulative effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is effective (that is, a modified-retrospective approach). For certain assets (such as debt securities for which other-than-temporary impairment has been recognized before the effective date and PCD assets), a prospective transition approach is required. For existing purchased credit impaired assets, upon adoption, the amortized cost basis is adjusted to reflect the addition of the ACL. This transition relief avoids the need for a reporting entity to reassess its purchased financial assets that exist as of the date of adoption in order to determine whether they would have met, at acquisition, the new criteria of 'more-than insignificant' credit deterioration since origination. The transition relief also allows an entity to accrete the remaining noncredit discount (based on the revised amortized cost basis) into interest income over the life of the related asset using the interest method. Under the standard, the Company will determine the ACL based upon a consideration of its historical loss experience, current borrower-specific risk characteristics, forecasts of future economic conditions and other relevant factors. In doing so, the method for determining estimated credit losses will move from an “incurred loss” model to a “life of loan” model. For public business entities, this new amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. The Company’s adoption of this guidance as of January 1, 2020, which was based upon forecasted economic conditions and portfolio balances existing as of December 31, 2019, resulted in the following: • an increase in the ACL on funded loans of $72 million: ◦ amount includes a $28 million adjustment to the amortized cost basis of PCD loans; • an increase in the ACL on off-balance-sheet commitments of $15 million; • the establishment of an ACL on held-to-maturity debt securities of $2 million; and • a decrease in retained earnings of $46 million, net of tax. The increase in aggregate loan allowance levels was driven, primarily, by higher reserve requirements associated with the Company’s retail portfolios (i.e. residential mortgage and home equity) due to the difference between the loss emergence periods of these portfolios under the prior incurred loss model and the expected remaining life of such loans as required by the standard, partially offset by lower reserve requirements associated with certain of the Company’s commercial portfolios, which generally have shorter contractual maturities. The liability for off-balance sheet commitments reflects the inclusion of lifetime losses for expected funding over the remaining life of such exposures. The Company’s held-to-maturity debt securities portfolio consists primarily of agency-backed securities and highly-rated municipal and corporate bonds, all of which inherently have minimal non-payment risk. In accordance with the amended guidance, the Company elected the practical expedients related to (i) the presentation of accrued interest receivable, net of the ACL, in other assets within the Consolidated Statements of Condition and (ii) the exclusion, for disclosure purposes, of accrued interest balances from the amortized cost basis of the loan portfolio. The adjustments noted above serve to reduce regulatory capital ratios for both the Holding Company and the Bank by approximately 10 basis points. In December 2018, the Federal banking agencies approved a final rule allowing an option to phase-in, over three years, the day one regulatory capital effects of the standard. In March 2020, the Federal banking agencies issued an interim final rule providing an alternative option to delay, for two years, an estimate of the standard’s effect on regulatory capital (relative to incurred loss methodology's effect on regulatory capital), followed by a three-year transition period. The Company has elected the alternative option provided in the March 2020 interim final rule. The amended guidance also requires expanded disclosures. See Note 2, "Securities", Note 3, "Loans" and Note 4, "Allowance for Credit Losses" for the new disclosures required by the standard, including further discussion of the Company’s accounting policies and methodologies used to estimate expected credit losses beginning in 2020. Simplifying the Test for Goodwill Impairment In January 2017, the FASB amended its standards with respect to goodwill, simplifying how an entity is required to conduct the impairment assessment by eliminating Step 2, which required a hypothetical purchase price allocation, from the goodwill impairment test. Instead, goodwill impairment will now be measured as the amount by which a reporting unit’s carrying amount exceeds its fair value, not to exceed the carrying amount of goodwill. An entity will still have the option to perform a qualitative assessment to determine if a quantitative impairment test is necessary. For public business entities, this new guidance is effective in fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019 (January 1, 2020 for People’s United) and is to be applied prospectively. Early adoption is permitted for any impairment tests performed after January 1, 2017. This amendment, which the Company elected to early adopt effective January 1, 2018, did not impact the Company’s Consolidated Financial Statements as of and for the period ended March 31, 2020. Disclosure Requirements – Fair Value Measurement In August 2018, the FASB issued targeted amendments that serve to eliminate, add and modify certain disclosure requirements for fair value measurements. Among the changes, entities are no longer required to disclose the amount of and reasons for transfers between Level 1 and Level 2 of the fair value hierarchy, but are required to disclose the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. These amendments are effective for interim and annual reporting periods beginning after December 15, 2019 (January 1, 2020 for People’s United) and early adoption is permitted. Entities may also elect to (i) early adopt the eliminated and/or modified disclosure requirements and (ii) delay adoption of the new disclosure requirements until their effective date. The provisions set forth in this guidance, which the Company elected to early adopt in 2018, have been reflected in Note 12 (as applicable) and did not have a significant impact on the Company’s Consolidated Financial Statements. Reference Rate Reform In March 2020, the FASB issued a new standard providing temporary optional expedients and exceptions to existing U.S. GAAP on contract modifications and hedge accounting in order to ease the financial reporting burdens associated with transitioning away from LIBOR and other interbank offered rates to acceptable alternative rates. Under the new guidance, an entity can elect, by accounting topic or industry subtopic, to account for the modification of a contract affected by reference rate reform as a continuation of the existing contract, if certain conditions are met. In addition, the new guidance allows an entity to elect, on a hedge-by-hedge basis, to continue to apply hedge accounting for hedging relationships in which the critical terms change due to reference rate reform, if certain conditions are met. A one-time election to sell and/or transfer held-to-maturity debt securities that reference a rate affected by reference rate reform is also permitted under the new guidance. While the standard is effective upon issuance, the Company continues to evaluate the impact and which optional expedients and exceptions might be elected. These optional elections will generally cease to apply to contract modifications or existing hedging relationships after December 31, 2022. Standards effective in 2021 Disclosure Requirements – Defined Benefit Plans In August 2018, the FASB issued targeted amendments that serve to make minor changes to the disclosure requirements for employers that sponsor defined benefit pension and/or other postretirement benefit plans. More specifically, the amendments (i) remove disclosures that are no longer considered cost beneficial; (ii) clarify the specific requirements of selected disclosures; and (iii) add disclosure requirements identified as relevant. These amendments are effective for fiscal years ending after December 15, 2020 (January 1, 2021 for People’s United) and early adoption is permitted. The provisions set forth in this guidance, which the Company elected to early adopt in 2018, have been reflected in Note 9 (as applicable) and did not have a significant impact on the Company’s Consolidated Financial Statements. Simplifying the Accounting for Income Taxes In December 2019, the FASB amended its standards with respect to income taxes, simplifying the accounting in several areas, including intra-period tax allocation, deferred tax liabilities related to outside basis differences, and year-to-date losses in interim periods, among others. For public business entities, this new guidance is effective in fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020 (January 1, 2021 for People’s United) and early adoption is permitted. If an entity elects to early adopt, it must adopt all changes as a result of the guidance. Adoption of this standard is not expected to have a significant impact on the Company’s Consolidated Financial Statements .

Employee Benefit Plans (Policie

Employee Benefit Plans (Policies)	3 Months Ended
	Mar. 31, 2020
People's United Employee Pension and Other Postretirement Plans	People’s United Employee Pension and Other Postretirement Plans People’s United maintains a qualified noncontributory defined benefit pension plan (the “People’s Qualified Plan”) that covers substantially all full-time and part-time employees who (i) meet certain age and length of service requirements and (ii) were employed by the Bank prior to August 14, 2006. Benefits are based upon the employee’s years of credited service and either the average compensation for the last five years or the average compensation for the five New employees of the Bank starting on or after August 14, 2006 are not eligible to participate in the People’s Qualified Plan. Instead, the Bank makes contributions on behalf of these employees to a qualified defined contribution plan in an annual amount equal to 3% of the employee’s eligible compensation. Employee participation in this plan is restricted to employees who (i) are at least 18 years of age and (ii) worked at least 1,000 hours in a year. Both full-time and part-time employees are eligible to participate as long as they meet these requirements. In July 2011, the Bank amended the People’s Qualified Plan to “freeze”, effective December 31, 2011, the accrual of pension benefits for People’s Qualified Plan participants. As such, participants will not earn any additional benefits after that date. Instead, effective January 1, 2012, the Bank began making contributions on behalf of these participants to a qualified defined contribution plan in an annual amount equal to 3% of the employee’s eligible compensation. In addition to the People’s Qualified Plan, People’s United continues to maintain qualified defined benefit pension plans that cover (i) former First Connecticut Bancorp, Inc. employees who meet certain eligibility requirements (the “First Connecticut Qualified Plan”) and (ii) former United Financial Bancorp, Inc. employees who meet certain eligibility requirements (the “United Financial Qualified Plan”). All benefits under these plans were frozen effective February 28, 2013 and December 31, 2012, respectively. People’s United’s funding policy is to contribute the amounts required by applicable regulations, although additional amounts may be contributed from time to time. People’s United also maintains (i) unfunded, nonqualified supplemental plans to provide retirement benefits to certain senior officers (the “People’s Supplemental Plans”) and (ii) an unfunded plan that provides retirees with optional medical, dental and life insurance benefits (the “People’s Postretirement Plan”). People’s United accrues the cost of these postretirement benefits over the employees’ years of service to the date of their eligibility for such benefit. People’s United also continues to maintain: (1) for certain eligible former First Connecticut Bancorp, Inc. employees (i) an unfunded, nonqualified supplemental retirement plan (the “First Connecticut Supplemental Plan”) and (ii) unfunded plans that provide medical, dental and life insurance benefits (the “First Connecticut Postretirement Plans”); (2) for certain eligible former BSB Bancorp, Inc. employees (i) an unfunded, nonqualified supplemental retirement plan (the “BSB Bancorp Supplemental Plan”) and (ii) unfunded plans that provide life insurance benefits (the “BSB Bancorp Post Retirement Welfare (Life Insurance) Plan”); and (3) for certain former United Financial Bancorp, Inc. employees (i) an unfunded, nonqualified supplemental retirement plan (the “United Financial Supplemental Plan”) and (ii) unfunded plans that provide medical, dental and life insurance benefits (the “United Financial Postretirement Benefit Plan”).
Employee Stock Ownership Plan	Employee Stock Ownership Plan In April 2007, People’s United established an ESOP. At that time, People’s United loaned the ESOP $216.8 million to purchase 10,453,575 shares of People’s United common stock in the open market. In order for the ESOP to repay the loan, People’s United expects to make annual cash contributions of approximately $18.8 million until 2036. Such cash contributions may be reduced by the cash dividends paid on unallocated ESOP shares, which, for the three months ended March 31, 2020, totaled $1.1 million. At March 31, 2020, the loan balance totaled $171.8 million. Employee participation in this plan is restricted to those employees who (i) are at least 18 years of age and (ii) worked at least 1,000 hours within 12 months of their hire date or any plan year (January 1 to December 31) after their date of hire. Employees meeting the aforementioned eligibility criteria during the plan year must continue to be employed as of the last day of the plan year in order to receive an allocation of shares for that plan year. Shares of People’s United common stock are held by the ESOP and allocated to eligible participants annually based upon a percentage of each participant’s eligible compensation. Since the ESOP was established, a total of 4,616,996 shares of People’s United common stock have been allocated or committed to be released to participants’ accounts. At March 31, 2020, 5,836,579 shares of People’s United common stock, with a fair value of $64.5 million at that date, have not been allocated or committed to be released. Compensation expense related to the ESOP is recognized at an amount equal to the number of common shares committed to be released by the ESOP for allocation to participants’ accounts multiplied by the average fair value of People’s United’s common stock during the reporting period. The difference between the fair value of the shares of People’s United’s common stock committed to be released and the cost of those common shares is recorded as a credit to additional paid-in capital (if fair value exceeds cost) or, to the extent that no such credits remain in additional paid-in capital, as a charge to retained earnings (if fair value is less than cost). Expense recognized for the ESOP totaled $1.2 million and $1.4 million for the three months ended March 31, 2020 and 2019, respectively.
Recurring
Fair Value Measurements	Recurring Fair Value Measurements Trading Debt Securities, Equity Securities and Debt Securities Available-For-Sale When available, People’s United uses quoted market prices for identical securities received from an independent, nationally-recognized, third-party pricing service (as discussed further below) to determine the fair value of investment securities such as U.S. Treasury and agency securities and equity securities that are included in Level 1. When quoted market prices for identical securities are unavailable, People’s United uses prices provided by the independent pricing service based on recent trading activity and other observable information including, but not limited to, market interest rate curves, referenced credit spreads and estimated prepayment rates where applicable. These investments include certain U.S. and government agency debt securities, corporate and municipal debt securities, and GSE mortgage-backed and CMO securities, all of which are included in Level 2. The Company’s available-for-sale debt securities are primarily comprised of GSE mortgage-backed securities. The fair value of these securities is based on prices obtained from the independent pricing service. The pricing service uses various techniques to determine pricing for the Company’s mortgage-backed securities, including option pricing and discounted cash flow analysis. The inputs include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, benchmark securities, bids, offers, reference data, monthly payment information and collateral performance. At both March 31, 2020 and December 31, 2019, the entire available-for-sale mortgage-backed securities portfolio was comprised of GSE mortgage-backed and CMO securities with original final maturities ranging from 10 to 40 years. An active market exists for securities that are similar to the Company’s GSE mortgage-backed and CMO securities, making observable inputs readily available.
Nonrecurring
Fair Value Measurements	Non-Recurring Fair Value Measurements Loans Held-for-Sale Loans held-for-sale are recorded at the lower of amortized cost or fair value and are therefore measured at fair value on a non-recurring basis. When available, People’s United uses observable secondary market data, including pricing on recent closed market transactions for loans with similar characteristics. Accordingly, such loans are classified as Level 2 measurements. When observable data is unavailable, valuation methodologies using current market interest rate data adjusted for inherent credit risk are used, and such loans are included in Level 3. REO and Repossessed Assets REO and repossessed assets are recorded at the lower of cost or fair value, less estimated selling costs, and are therefore measured at fair value on a non-recurring basis. People’s United has estimated the fair values of these assets using Level 3 inputs, such as independent third-party appraisals and price opinions. Such appraisals are based on the market and/or income approach to value and are subject to a discount (to reflect estimated cost to sell) that generally approximates 10%. Assets that are acquired through loan default are recorded as held-for-sale initially at the lower of the recorded investment in the loan or fair value (less estimated selling costs) upon the date of foreclosure/repossession. Subsequent to foreclosure/repossession, valuations are updated periodically and the carrying amounts of these assets may be reduced further. Mortgage Servicing Rights Mortgage servicing rights are evaluated for impairment based upon the fair value of the servicing rights as compared to their amortized cost. The fair value of mortgage servicing rights is based on a valuation model that calculates the present value of estimated net servicing income. This model incorporates certain assumptions that market participants would likely use in estimating future net servicing income, such as interest rates, prepayment speeds and the cost to service (including delinquency and foreclosure costs), all of which require a degree of management judgment. Adjustments are only recorded when the discounted cash flows derived from the valuation model are less than the carrying value of the asset. As such, mortgage servicing rights are subject to measurement at fair value on a non-recurring basis and are classified as Level 3 assets. Collateral Dependent / Impaired Loans (periods prior to January 1, 2020) The Company’s approach to determining the fair value of collateral dependent loans is described in Note 3, “Loans”. At March 31, 2020, collateral dependent loans with an amortized cost of $15.2 million had a corresponding ACL (determined using a Level 3 measurement approach) of $8.9 million. The provision for credit losses associated with collateral dependent loans totaled $3.9 million for the three months ended March 31, 2020. Prior to the Company's adoption of the CECL standard, loan impairment was deemed to exist when full repayment of principal and interest according to the contractual terms of the loan was no longer probable. Impaired loans were reported based on one of three measures: (i) the present value of expected future cash flows discounted at the loan’s original effective interest rate; (ii) the loan’s observable market price; or (iii) the fair value of the collateral (less estimated cost to sell) if the loan is collateral dependent. Accordingly, certain impaired loans may have been subject to measurement at fair value on a non-recurring basis. People’s United has estimated the fair values of these assets using Level 3 inputs, such as discounted cash flows based on inputs that are largely unobservable and, instead, reflect management’s own estimates of the assumptions a market participant would use in pricing such loans and/or the fair value of collateral based on independent third-party appraisals for collateral dependent loans. Such appraisals are based on the market and/or income approach to value and are subject to a discount (to reflect estimated cost to sell) that generally approximates 10%.

Cash and Cash Equivalents and_2

Cash and Cash Equivalents and Securities (Tables)	3 Months Ended
	Mar. 31, 2020
Cash and Cash Equivalents [Abstract]
Available-for-Sale and Held-to-Maturity Debt Securities Gains (Losses)	The amortized cost, ACL, gross unrealized gains and losses, and fair value of People’s United’s debt securities available-for-sale and debt securities held-to-maturity are as follows: As of March 31, 2020 (in millions) Amortized ACL (1) Gross Gross Fair Debt securities available-for-sale: U.S. Treasury and agency $ 731.3 $ — $ 15.9 $ — $ 747.2 GSE (2) mortgage-backed and 3,425.1 — 104.4 (0.1) 3,529.4 Total debt securities $ 4,156.4 $ — $ 120.3 $ (0.1) $ 4,276.6 Debt securities held-to-maturity: State and municipal $ 2,574.9 $ 0.1 $ 151.4 $ (1.5) $ 2,724.9 GSE mortgage-backed securities 1,190.8 — 49.7 — 1,240.5 Corporate 96.2 1.8 1.6 (1.3) 98.3 Other 1.5 — — — 1.5 Total debt securities $ 3,863.4 $ 1.9 $ 202.7 $ (2.8) $ 4,065.2 (1) As discussed in Note 15, beginning January 1, 2020, an ACL is required to be recognized (as appropriate) for debt securities. (2) Government sponsored enterprise (3) Collateralized mortgage obligation As of December 31, 2019 (in millions) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Debt securities available-for-sale: U.S. Treasury and agency $ 689.5 $ 0.4 $ (2.8) $ 687.1 GSE mortgage-backed and CMO securities 2,856.3 25.0 (4.1) 2,877.2 Total debt securities available-for-sale $ 3,545.8 $ 25.4 $ (6.9) $ 3,564.3 Debt securities held-to-maturity: State and municipal $ 2,503.9 $ 142.0 $ (0.4) $ 2,645.5 GSE mortgage-backed securities 1,271.4 8.0 (0.3) 1,279.1 Corporate 92.4 1.5 — 93.9 Other 1.5 — — 1.5 Total debt securities held-to-maturity $ 3,869.2 $ 151.5 $ (0.7) $ 4,020.0
Summary of debt securities, held to maturity, credit quality	The table below indicates the credit profile of the Company's debt securities held-to-maturity at amortized cost: As of March 31, 2020 (in millions) Investment Grade Non-Investment Grade Total State and municipal $ 2,574.5 $ 0.4 $ 2,574.9 GSE mortgage-backed securities 1,190.8 — 1,190.8 Corporate 91.2 5.0 96.2 Other 1.5 — 1.5 Total $ 3,858.0 $ 5.4 $ 3,863.4
Continuous Unrealized Loss Position on Available-for-Sale and Held-to-Maturity Securities	The following table summarizes those debt securities available-for-sale with unrealized losses at March 31, 2020, classified as to the length of time the losses have existed and, for which no ACL has been recognized: Continuous Unrealized Loss Position Less Than 12 Months 12 Months Or Longer Total As of March 31, 2020 (in millions) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Debt securities available-for-sale: GSE mortgage-backed and CMO $ 10.9 $ (0.1) $ — $ — $ 10.9 $ (0.1) Total $ 10.9 $ (0.1) $ — $ — $ 10.9 $ (0.1) The following table summarizes those debt securities with unrealized losses at December 31, 2019, classified as to the length of time the unrealized losses have existed. Certain unrealized losses totaled less than $0.1 million. Continuous Unrealized Loss Position Less Than 12 Months 12 Months Or Longer Total As of December 31, 2019 (in millions) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Debt securities available-for-sale: GSE mortgage-backed and CMO $ 565.4 $ (3.1) $ 509.3 $ (1.0) $ 1,074.7 $ (4.1) U.S. Treasury and agency 181.0 (0.4) 362.4 (2.4) 543.4 (2.8) Total debt securities available-for-sale $ 746.4 $ (3.5) $ 871.7 $ (3.4) $ 1,618.1 $ (6.9) Debt securities held-to-maturity: GSE mortgage-backed securities $ 100.9 $ (0.3) $ 9.1 $ — $ 110.0 $ (0.3) State and municipal 33.0 (0.2) 11.4 (0.2) 44.4 (0.4) Corporate 3.5 — 8.6 — 12.1 — Total debt securities held-to-maturity $ 137.4 $ (0.5) $ 29.1 $ (0.2) $ 166.5 $ (0.7)
Summary of Amortized Cost and Fair Value of Debt Securities Based on Remaining Period to Contractual Maturity	The following table is a summary of the amortized cost and fair value of debt securities as of March 31, 2020, based on remaining period to contractual maturity. Information for GSE mortgage-backed and CMO securities is based on the final contractual maturity dates without considering repayments and prepayments. Available-for-Sale Held-to-Maturity (in millions) Amortized Cost Fair Value Amortized Cost Fair Value U.S. Treasury and agency: Within 1 year $ 200.8 $ 201.4 $ — $ — After 1 but within 5 years 530.5 545.8 — — Total 731.3 747.2 — — GSE mortgage-backed and CMO securities: After 1 but within 5 years 83.2 87.3 841.2 879.3 After 5 but within 10 years 880.8 918.9 77.5 82.4 After 10 years 2,461.1 2,523.2 272.1 278.8 Total 3,425.1 3,529.4 1,190.8 1,240.5 State and municipal: Within 1 year — — 10.0 10.0 After 1 but within 5 years — — 245.5 254.3 After 5 but within 10 years — — 471.4 499.4 After 10 years — — 1,848.0 1,961.2 Total — — 2,574.9 2,724.9 Corporate: Within 1 year — — 5.0 5.0 After 1 but within 5 years — — 2.5 2.5 After 5 but within 10 years — — 88.7 90.8 Total — — 96.2 98.3 Other: Within 1 year — — 1.5 1.5 Total — — 1.5 1.5 Total: Within 1 year 200.8 201.4 16.5 16.5 After 1 but within 5 years 613.7 633.1 1089.2 1,136.1 After 5 but within 10 years 880.8 918.9 637.6 672.6 After 10 years 2,461.1 2,523.2 2,120.1 2,240.0 Total $ 4,156.4 $ 4,276.6 $ 3,863.4 $ 4,065.2

Loans (Tables)

Loans (Tables)	3 Months Ended
	Mar. 31, 2020
Receivables [Abstract]
Summary of Loans by Loan Portfolio Segment and Class	The following table summarizes People’s United’s loans by loan portfolio segment and class: (in millions) March 31, 2020 December 31, 2019 Commercial: Commercial real estate $ 14,651.6 $ 14,762.3 Commercial and industrial 9,097.7 8,693.2 Equipment financing 5,012.7 4,910.4 MWABL 2,948.0 2,348.4 Total Commercial Portfolio 31,710.0 30,714.3 Retail: Residential mortgage: Adjustable-rate 6,825.2 7,064.8 Fixed-rate 3,256.7 3,253.3 Total residential mortgage 10,081.9 10,318.1 Home equity and other consumer: Home equity 2,349.9 2,406.5 Other consumer 142.2 157.2 Total home equity and other consumer 2,492.1 2,563.7 Total Retail Portfolio 12,574.0 12,881.8 Total loans $ 44,284.0 $ 43,596.1
Summary of Aging Information by Class of Loan	The following tables summarize aging information by class of loan: Past Due As of March 31, 2020 (in millions) Current 30-89 Days 90 Days or More Total Total Commercial: Commercial real estate $ 14,580.0 $ 43.7 $ 27.9 $ 71.6 $ 14,651.6 Commercial and industrial 9,055.4 18.8 23.5 42.3 9,097.7 Equipment financing 4,853.2 136.4 23.1 159.5 5,012.7 MWABL 2,948.0 — — — 2,948.0 Total 31,436.6 198.9 74.5 273.4 31,710.0 Retail: Residential mortgage 9,978.3 64.2 39.4 103.6 10,081.9 Home equity 2,325.3 13.3 11.3 24.6 2,349.9 Other consumer 141.2 0.9 0.1 1.0 142.2 Total 12,444.8 78.4 50.8 129.2 12,574.0 Total loans $ 43,881.4 $ 277.3 $ 125.3 $ 402.6 $ 44,284.0 Past Due As of December 31, 2019 (in millions) Current 30-89 Days 90 Days or More Total Total Commercial: Commercial real estate $ 14,713.8 $ 22.3 $ 26.2 $ 48.5 $ 14,762.3 Commercial and industrial 11,010.7 13.1 17.8 30.9 11,041.6 Equipment financing 4,791.0 97.9 21.5 119.4 4,910.4 Total 30,515.5 133.3 65.5 198.8 30,714.3 Retail: Residential mortgage 10,215.9 65.5 36.7 102.2 10,318.1 Home equity 2,385.7 9.9 10.9 20.8 2,406.5 Other consumer 156.1 1.1 — 1.1 157.2 Total 12,757.7 76.5 47.6 124.1 12,881.8 Total loans $ 43,273.2 $ 209.8 $ 113.1 $ 322.9 $ 43,596.1
Summarized Recorded Investments, by Class of Loan, in Originated Non-Performing Loans	The recorded investment in non-accrual loans, by class of loan and year of origination, is summarized as follows: March 31, 2020 Dec. 31, 2019 Non-Accrual Loans (in millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Non-Accrual Loans With No ACL Non-Accrual Loans Commercial: Commercial real estate $ — $ 16.3 $ 2.1 $ 2.1 $ 4.9 $ 28.0 $ 0.1 $ 53.5 $ 5.3 $ 53.8 Commercial and industrial 0.3 2.9 0.6 2.2 2.1 14.7 31.7 54.5 7.2 38.5 Equipment financing 0.9 10.6 13.4 8.6 4.3 4.7 — 42.5 1.9 47.7 MWABL — — — — — — 1.1 1.1 — — Total (1) 1.2 29.8 16.1 12.9 11.3 47.4 32.9 151.6 14.4 140.0 Retail: Residential mortgage — 1.3 3.2 2.3 1.4 58.4 — 66.6 22.0 63.3 Home equity — — 0.1 — 0.2 3.7 18.1 22.1 5.6 20.8 Other consumer — — 0.1 — — — — 0.1 — — Total (2) — 1.3 3.4 2.3 1.6 62.1 18.1 88.8 27.6 84.1 Total $ 1.2 $ 31.1 $ 19.5 $ 15.2 $ 12.9 $ 109.5 $ 51.0 $ 240.4 $ 42.0 $ 224.1 (1) Reported net of government guarantees totaling $1.2 million and $1.3 million at March 31, 2020 and December 31, 2019, respectively. These government guarantees relate, almost entirely, to guarantees provided by the Small Business Administration as well as selected other Federal agencies and represent the carrying value of the loans that are covered by such guarantees, the extent of which (i.e. full or partial) varies by loan. At March 31, 2020, all of the government guarantees related to commercial and industrial loans. (2) Includes $25.4 million and $17.0 million of loans in the process of foreclosure at March 31, 2020 and December 31, 2019, respectively.
Summary of Recorded Investments in TDRs by Class of Loan	The following tables summarize, by class of loan, the recorded investments in loans modified as TDRs during the three months ended March 31, 2020 and 2019. For purposes of this disclosure, recorded investments represent amounts immediately prior to and subsequent to the restructuring. Three Months Ended March 31, 2020 (dollars in millions) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial: Commercial real estate (1) 5 $ 3.7 $ 3.7 Commercial and industrial (2) 10 9.0 9.0 Equipment financing (3) 9 3.1 3.1 MWABL — — — Total 24 15.8 15.8 Retail: Residential mortgage (4) 13 6.2 6.2 Home equity (5) 17 2.1 2.1 Other consumer — — — Total 30 8.3 8.3 Total 54 $ 24.1 $ 24.1 (1) Represents the following concessions: extension of term (4 contracts; recorded investment of $3.2 million); or a reduced payment and/or payment deferral (1 contract; recorded investment of $0.5 million). (2) Represents the following concessions: extension of term (5 contracts; recorded investment of $7.4 million); reduced payment and/or payment deferral (1 contract; recorded investment of $0.3 million); or a combination of concessions (4 contract; recorded investment of $1.3 million). (3) Represents the following concessions: extension of term (1 contract; recorded investment of $1.2 million); reduced payment and/or payment deferral (5 contracts; recorded investment of $0.5 million); or a combination of concessions (3 contracts; recorded investment of $1.4 million). (4) Represents the following concessions: loans restructured through bankruptcy (3 contracts; recorded investment of $0.6 million); reduced payment and/or payment deferral (9 contracts; recorded investment of $5.5 million); or a combination of concessions (1 contract; recorded investment of $0.1 million). (5) Represents the following concessions: loans restructured through bankruptcy (5 contracts; recorded investment of $0.5 million); reduced payment and/or payment deferral (1 contract; recorded investment of $0.1 million); or a combination of concessions (11 contracts; recorded investment of $1.5 million). Three Months Ended March 31, 2019 (dollars in millions) Number of Contracts Pre-Modification Outstanding Recorded Investment Post-Modification Outstanding Recorded Investment Commercial: Commercial real estate (1) 2 $ 3.0 $ 3.0 Commercial and industrial (2) 4 1.4 1.4 Equipment financing (3) 14 7.3 7.3 Total 20 11.7 11.7 Retail: Residential mortgage (4) 20 5.6 5.6 Home equity (5) 22 2.1 2.1 Other consumer — — — Total 42 7.7 7.7 Total 62 $ 19.4 $ 19.4 (1) Represents the following concession: reduced payment and/or payment deferral (2 contracts; recorded investment of $3.0 million). (2) Represents the following concessions: extension of term (4 contracts; recorded investment of $1.4 million). (3) Represents the following concessions: extension of term (8 contracts; recorded investment of $6.6 million); reduced payment and/or payment deferral (5 contracts; recorded investment of $0.5 million); or a combination of concessions (1 contract; recorded investment of $0.2 million). (4) Represents the following concessions: loans restructured through bankruptcy (9 contracts; recorded investment of $1.1 million); reduced payment and/or payment deferral (5 contracts; recorded investment of $2.2 million); or a combination of concessions (6 contracts; recorded investment of $2.3 million). (5) Represents the following concessions: loans restructured through bankruptcy (9 contracts; recorded investment of $0.6 million); reduced payment and/or payment deferral (3 contracts; recorded investment of $0.5 million); or a combination of concessions (10 contracts; recorded investment of $1.0 million).
Summary of Recorded Investments in TDRs by Class of Loan, Subsequently Defaulted	The following is a summary, by class of loan, of information related to TDRs completed within the previous 12 months that subsequently defaulted during the three months ended March 31, 2020 and 2019. For purposes of this disclosure, the previous 12 months is measured from April 1 of the respective prior year and a default represents a previously-modified loan that became past due 30 days or more during the three months ended March 31, 2020 or 2019. Three Months Ended March 31, 2020 2019 (dollars in millions) Number of Contracts Recorded Investment as of Period End Number of Contracts Recorded Investment as of Period End Commercial: Commercial real estate — $ — — $ — Commercial and industrial 1 0.1 — — Equipment financing 4 2.5 2 2.9 MWABL — — — — Total 5 2.6 2 2.9 Retail: Residential mortgage 3 1.3 3 1.3 Home equity 1 — 2 0.4 Other consumer — — — — Total 4 1.3 5 1.7 Total 9 $ 3.9 7 $ 4.6
Summary of Credit Quality Indicators by Class of Loan	The following table presents Commercial loan risk ratings, by class of loan and year of origination, as of March 31, 2020: (in millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Commercial real estate: Pass $ 335.3 $ 1,762.3 $ 1,730.4 $ 1,703.1 $ 1,584.0 $ 6,615.0 $ 380.7 $ 14,110.8 Special Mention — 8.7 91.4 28.0 38.6 115.3 2.4 284.4 Substandard 2.3 29.3 22.9 29.2 6.6 161.6 2.9 254.8 Doubtful — — — — — 1.6 — 1.6 Total $ 337.6 $ 1,800.3 $ 1,844.7 $ 1,760.3 $ 1,629.2 $ 6,893.5 $ 386.0 $ 14,651.6 Commercial and industrial: Pass $ 674.1 $ 1,876.3 $ 1,015.3 $ 801.6 $ 635.6 $ 1,930.1 $ 1,635.0 $ 8,568.0 Special Mention 2.1 11.5 22.3 6.1 39.8 63.1 41.9 186.8 Substandard 0.7 11.5 57.0 37.0 12.3 127.4 93.5 339.4 Doubtful — — — 0.6 1.2 — 1.7 3.5 Total $ 676.9 $ 1,899.3 $ 1,094.6 $ 845.3 $ 688.9 $ 2,120.6 $ 1,772.1 $ 9,097.7 Equipment financing: Pass $ 556.4 $ 1,843.0 $ 1,068.9 $ 587.7 $ 303.1 $ 164.3 $ — $ 4,523.4 Special Mention 13.5 33.7 16.1 10.9 4.4 1.7 — 80.3 Substandard 45.2 161.2 101.8 56.5 13.1 31.2 — 409.0 Doubtful — — — — — — — — Total $ 615.1 $ 2,037.9 $ 1,186.8 $ 655.1 $ 320.6 $ 197.2 $ — $ 5,012.7 MWABL: Pass $ 2.6 $ 10.8 $ 15.0 $ 6.6 $ 21.0 $ 62.7 $ 2,697.0 $ 2,815.7 Special Mention — 7.3 — — — — 68.6 75.9 Substandard — — — 1.9 0.7 1.9 51.9 56.4 Doubtful — — — — — — — — Total $ 2.6 $ 18.1 $ 15.0 $ 8.5 $ 21.7 $ 64.6 $ 2,817.5 $ 2,948.0 The following table presents Retail loan risk classification, by class of loan and year of origination, as of March 31, 2020: (in millions) 2020 2019 2018 2017 2016 Prior Revolving Loans Total Residential mortgage: Low Risk $ 51.5 $ 400.9 $ 423.9 $ 560.7 $ 1,130.5 $ 1,937.1 $ — $ 4,504.6 Moderate Risk 132.7 640.0 835.4 967.7 928.3 1,335.1 — 4,839.2 High Risk 26.4 79.8 117.6 114.1 104.8 295.4 — 738.1 Total $ 210.6 $ 1,120.7 $ 1,376.9 $ 1,642.5 $ 2,163.6 $ 3,567.6 $ — $ 10,081.9 Home equity: Low Risk $ — $ — $ — $ — $ — $ 31.7 $ 335.2 $ 366.9 Moderate Risk 0.4 15.3 12.1 6.1 3.2 35.2 689.5 761.8 High Risk 2.0 27.9 83.0 68.0 27.5 14.3 998.5 1,221.2 Total $ 2.4 $ 43.2 $ 95.1 $ 74.1 $ 30.7 $ 81.2 $ 2,023.2 $ 2,349.9 Other consumer: Low Risk $ 1.6 $ 10.0 $ 6.3 $ 1.5 $ 0.5 $ 4.8 $ — $ 24.7 Moderate Risk — 0.1 0.2 0.1 0.2 5.3 — 5.9 High Risk 3.3 58.2 42.5 3.8 0.8 3.0 — 111.6 Total $ 4.9 $ 68.3 $ 49.0 $ 5.4 $ 1.5 $ 13.1 $ — $ 142.2 The following tables present Commercial and Retail credit quality indicators as of December 31, 2019: (in millions) Commercial Real Estate Commercial and Industrial Equipment Financing Total Commercial: Pass $ 14,222.3 $ 10,391.7 $ 4,433.5 $ 29,047.5 Special mention 334.3 330.4 76.5 741.2 Substandard 202.6 315.8 400.4 918.8 Doubtful 3.1 3.7 — 6.8 Total $ 14,762.3 $ 11,041.6 $ 4,910.4 $ 30,714.3 (in millions) Residential Mortgage Home Equity Other Consumer Total Retail: Low risk $ 4,410.0 $ 747.3 $ 24.9 $ 5,182.2 Moderate risk 4,958.3 548.5 5.9 5,512.7 High risk 949.8 1,110.7 126.4 2,186.9 Total $ 10,318.1 $ 2,406.5 $ 157.2 $ 12,881.8

Allowance For Credit Losses (Ta

Allowance For Credit Losses (Tables)	3 Months Ended
	Mar. 31, 2020
Allowance for Credit Loss [Abstract]
Summary, by Loan Portfolio Segment, of Activity in Allowance for Loan Losses	The following tables present a summary, by loan portfolio segment, of activity in the ACL for the three months ended March 31, 2020 and 2019: Three months ended March 31, 2020 (in millions) Commercial Retail Total Balance at beginning of period, $ 217.9 $ 28.7 $ 246.6 CECL transition adjustment (17.3) 89.5 72.2 Charge-offs (9.7) (2.9) (12.6) Recoveries 1.4 0.6 2.0 Net loan charge-offs (8.3) (2.3) (10.6) Provision for credit losses 19.5 14.0 33.5 Balance at end of period $ 211.8 $ 129.9 $ 341.7 Three months ended March 31, 2019 (in millions) Commercial Retail Total Balance at beginning of period $ 209.5 $ 30.9 $ 240.4 Charge-offs (6.4) (1.1) (7.5) Recoveries 1.4 1.0 2.4 Net loan charge-offs (5.0) (0.1) (5.1) Provision for credit losses 4.5 1.1 5.6 Balance at end of period $ 209.0 $ 31.9 $ 240.9 The following table summarizes the changes in the ACL on off-balance sheet credit exposures: (in millions) Three Months Ended March 31, 2020 Balance at beginning of the period $ 5.6 CECL transition adjustment 14.5 Balance at beginning of period, adjusted 20.1 Provision charged (credited) to income 0.6 Balance at end of period $ 20.7

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Composition of Total Net Investment in Lease Financing Receivables	The composition of the Company’s total net investment in lease financing receivables included within equipment financing loans in the Consolidated Statements of Condition was as follows: (in millions) March 31, 2020 December 31, 2019 Lease payments receivable $ 1,451.7 $ 1,417.1 Estimated residual value of leased assets 128.7 128.0 Gross investment in lease financing receivables 1,580.4 1,545.1 Plus: Deferred origination costs 13.0 13.4 Less: Unearned income (158.5) (156.9) Total net investment in lease financing receivables $ 1,434.9 $ 1,401.6
Contractual Maturities of Lease Financing Receivables	The contractual maturities of the Company's lease financing receivables were as follows: (in millions) March 31, 2020 2020 (1) $ 408.6 2021 448.4 2022 340.8 2023 208.7 2024 117.7 Later years 56.2 Total $ 1,580.4 (1) Contractual maturities for the nine months remaining in 2020.
Lease Income	The following table summarizes People's United's total lease income: Three Months Ended (in millions) 2020 2019 Lease financing receivables $ 17.6 $ 15.5 Operating leases 12.6 12.7 Total lease income $ 30.2 $ 28.2
Lease Costs	The following tables provide the components of lease cost and supplemental information: Three Months Ended (in millions) 2020 2019 Operating lease cost $ 16.7 $ 15.3 Variable lease cost 3.1 2.3 Finance lease cost 0.1 — Sublease income (0.5) (0.4) Net lease cost $ 19.4 $ 17.2
Lease Costs	(dollars in millions) March 31, 2020 December 31, 2019 Lease ROU assets: Operating leases $ 275.9 $ 276.6 Finance leases 2.5 2.6 Lease liabilities: Operating leases 307.5 307.9 Finance leases 5.2 5.3 Weighted-average discount rate: Operating leases 3.12 % 3.13 % Finance leases 2.58 2.58 Weighted-average remaining lease term (in years): Operating leases 7.8 7.7 Finance leases 11.9 12.2 Three Months Ended (in millions) 2020 2019 Cash payments included in the measurement of lease liabilities: Reported in operating cash from operating leases $ 17.1 $ 15.4 Reported in financing cash from finance leases 0.1 — ROU assets obtained in exchange for lessee: Operating lease liabilities (1) 14.3 10.3 Finance lease liabilities (1) — — (1) Excludes related transition adjustment recorded during three months ended March 31, 2019 ( see above ).
Lease Right-of-use Assets and Liabilities	(dollars in millions) March 31, 2020 December 31, 2019 Lease ROU assets: Operating leases $ 275.9 $ 276.6 Finance leases 2.5 2.6 Lease liabilities: Operating leases 307.5 307.9 Finance leases 5.2 5.3 Weighted-average discount rate: Operating leases 3.12 % 3.13 % Finance leases 2.58 2.58 Weighted-average remaining lease term (in years): Operating leases 7.8 7.7 Finance leases 11.9 12.2 Three Months Ended (in millions) 2020 2019 Cash payments included in the measurement of lease liabilities: Reported in operating cash from operating leases $ 17.1 $ 15.4 Reported in financing cash from finance leases 0.1 — ROU assets obtained in exchange for lessee: Operating lease liabilities (1) 14.3 10.3 Finance lease liabilities (1) — — (1) Excludes related transition adjustment recorded during three months ended March 31, 2019 ( see above ).
Schedule of Contractual Maturities of Lease Liabilities	The contractual maturities of the Company's lease liabilities as of March 31, 2020 were as follows: (in millions) Operating Leases Finance Leases 2020 (1) $ 50.4 $ 0.4 2021 65.3 0.5 2022 47.7 0.5 2023 36.0 0.5 2024 30.0 0.5 Later years 121.0 3.7 Total lease payments 350.4 6.1 Less: Interest (42.9) (0.9) Total lease liabilities $ 307.5 $ 5.2 (1) Contractual maturities for the nine months remaining in 2020.

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Loss	The following is a summary of the changes in the components of accumulated other comprehensive income loss ("AOCL"), which are included in People’s United’s stockholders’ equity on an after-tax basis: (in millions) Pension and Other Postretirement Plans Net Unrealized Gains (Losses) on Debt Securities Available-for-Sale Net Unrealized Gains (Losses) on Debt Securities Transferred to Held-to-Maturity Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges Total AOCL Balance at December 31, 2019 $ (176.2) $ 20.8 $ (11.8) $ 0.3 $ (166.9) Other comprehensive income — 71.6 — — 71.6 Amounts reclassified from AOCL (1) 1.6 — 1.0 — 2.6 Current period other comprehensive 1.6 71.6 1.0 — 74.2 Balance at March 31, 2020 $ (174.6) $ 92.4 $ (10.8) $ 0.3 $ (92.7) (in millions) Pension and Other Postretirement Plans Net Unrealized Gains (Losses) on Debt Securities Available-for-Sale Net Unrealized Gains (Losses) on Debt Securities Transferred to Held-to-Maturity Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges Total AOCL Balance at December 31, 2018 $ (192.5) $ (47.0) $ (15.3) $ (2.0) $ (256.8) Other comprehensive income before — 29.0 — 0.5 29.5 Amounts reclassified from AOCL (1) 1.8 — 0.6 0.3 2.7 Current period other comprehensive 1.8 29.0 0.6 0.8 32.2 Balance at March 31, 2019 $ (190.7) $ (18.0) $ (14.7) $ (1.2) $ (224.6) (1) See the following table for details about these reclassifications.
Summary of Amounts Reclassified from AOCL	The following is a summary of the amounts reclassified from AOCL: Amounts Reclassified from AOCL Affected Line Item in the Statement Where Net Income is Presented Three Months Ended (in millions) 2020 2019 Details about components of AOCL: Amortization of pension and other Net actuarial loss $ (2.0) $ (1.3) (1) (2.0) (1.3) Income before income tax expense 0.4 (0.5) Income tax expense (1.6) (1.8) Net income Reclassification adjustment for net — — Income before income tax expense (2) — — Income tax expense — — Net income Amortization of unrealized losses on (1.3) (0.8) Income before income tax expense (3) 0.3 0.2 Income tax expense (1.0) (0.6) Net income Amortization of unrealized gains and Interest rate swaps — (0.4) (5) Interest rate locks (4) — — (5) — (0.4) Income before income tax expense — 0.1 Income tax expense — (0.3) Net income Total reclassifications for the period $ (2.6) $ (2.7) (1) Included in the computation of net periodic benefit income (expense) reflected in other non-interest expense (see Note 9 for additional details). (2) Included in other non-interest income. (3) Included in interest and dividend income - securities. (4) Amount reclassified from AOCL totaled less than $0.1 million for both periods (5) Included in interest expense - notes and debentures.

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Basic and Diluted Earnings Per Common Share, Reflecting Application of Two-Class Method	The following is an analysis of People’s United’s basic and diluted earnings per common share (“EPS”), reflecting the application of the two-class method, as described below: Three Months Ended (in millions, except per common share data) 2020 2019 Net income available to common shareholders $ 126.9 $ 111.1 Dividends paid on and undistributed earnings allocated to — — Earnings attributable to common shareholders $ 126.9 $ 111.1 Weighted average common shares outstanding for basic EPS 427.2 370.7 Effect of dilutive equity-based awards 2.6 3.4 Weighted average common shares and common-equivalent 429.8 374.1 EPS: Basic $ 0.30 $ 0.30 Diluted 0.30 0.30

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2020
Retirement Benefits [Abstract]
Components of Net Periodic Benefit (Income) Expense and Other Amounts	Components of net periodic benefit (income) expense and other amounts recognized in other comprehensive income (loss) for (i) the People’s Qualified Plan, the First Connecticut Qualified Plan, the People's Supplemental Plans, the First Connecticut Supplemental Plan, the BSB Bancorp Supplemental Plan and the United Financial Supplemental Plan (together the “Pension Plans”) and (ii) the People’s Postretirement Plan, the First Connecticut Postretirement Plans, the BSB Bancorp Post Retirement Welfare (Life Insurance) Plan and the United Financial Postretirement Plan (together the "Other Postretirement Plans") are as follows: Pension Plans Other Postretirement Plans Three months ended March 31 (in millions) 2020 2019 2020 2019 Net periodic benefit (income) expense: Interest cost $ 4.9 $ 5.6 $ 0.3 $ 0.3 Expected return on plan assets (12.4) (11.4) — — Recognized net actuarial loss 2.0 1.3 — — Settlements 0.8 0.6 — — Net periodic benefit (income) expense (1) (4.7) (3.9) 0.3 0.3 Other changes in plan assets and benefit obligations Net actuarial loss (2.0) (1.3) — — Prior service credit — — — — Total pre-tax changes recognized in other (2.0) (1.3) — — Total recognized in net periodic benefit (income) $ (6.7) $ (5.2) $ 0.3 $ 0.3

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables summarize People’s United’s financial instruments that are measured at fair value on a recurring basis: Fair Value Measurements Using As of March 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Debt securities available-for-sale: U.S. Treasury and agency $ 747.2 $ — $ — $ 747.2 GSE mortgage-backed and CMO securities — 3,529.4 — 3,529.4 Equity securities 6.2 — — 6.2 Other assets: Exchange-traded funds 39.8 — — 39.8 Mutual funds 2.9 — — 2.9 Interest rate swaps — 932.9 — 932.9 Interest rate caps — 3.6 — 3.6 Foreign exchange contracts — 8.6 — 8.6 Forward commitments to sell residential mortgage loans — 0.6 — 0.6 Total $ 796.1 $ 4,475.1 $ — $ 5,271.2 Financial liabilities: Interest rate swaps $ — $ 184.5 $ — $ 184.5 Interest rate caps — 3.6 — 3.6 Risk participation agreements — 0.5 — 0.5 Foreign exchange contracts — 9.2 — 9.2 Interest rate-lock commitments on residential mortgage loans — 0.7 — 0.7 Total $ — $ 198.5 $ — $ 198.5 Fair Value Measurements Using As of December 31, 2019 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Trading debt securities: U.S. Treasury $ 7.1 $ — $ — $ 7.1 Debt securities available-for-sale: U.S. Treasury and agency 687.1 — — 687.1 GSE mortgage-backed and CMO securities — 2,877.2 — 2,877.2 Equity securities 8.2 — — 8.2 Other assets: Exchange-traded funds 47.7 — — 47.7 Mutual funds 3.3 — — 3.3 Fixed income securities — — — — Interest rate swaps — 337.6 — 337.6 Interest rate caps — 1.7 — 1.7 Foreign exchange contracts — 1.2 — 1.2 Forward commitments to sell residential mortgage loans — 0.5 — 0.5 Total $ 753.4 $ 3,218.2 $ — $ 3,971.6 Financial liabilities: Interest rate swaps $ — $ 92.1 $ — $ 92.1 Interest rate caps — 1.7 — 1.7 Risk participation agreements — 0.1 — 0.1 Foreign exchange contracts — 1.8 — 1.8 Interest rate-lock commitments on residential mortgage loans — 0.5 — 0.5 Total $ — $ 96.2 $ — $ 96.2
Assets Measured at Fair Value on Non-Recurring Basis	The following tables summarize People’s United’s assets that are measured at fair value on a non-recurring basis: Fair Value Measurements Using As of March 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Loans held-for-sale (1) $ — $ 19.2 $ — $ 19.2 REO and repossessed assets (2) — — 21.4 21.4 Mortgage servicing rights (3) — — 7.7 7.7 Total $ — $ 19.2 $ 29.1 $ 48.3 Fair Value Measurements Using As of December 31, 2019 (in millions) Level 1 Level 2 Level 3 Total Loans held-for-sale: Commercial $ — $ — $ 157.9 $ 157.9 Other consumer — — 333.7 333.7 Residential (1) — 19.7 — 19.7 Impaired loans (4) — — 61.9 61.9 REO and repossessed assets (2) — — 23.4 23.4 Mortgage servicing rights — — 10.3 10.3 Total $ — $ 19.7 $ 587.2 $ 606.9 (1) Consists of residential mortgage loans; no fair value adjustments were recorded for the three months ended March 31, 2020 and 2019. (2) Represents: (i) $9.5 million of residential REO; (ii) $7.3 million of commercial REO; and (iii) $4.6 million of repossessed assets at March 31, 2020. Charge-offs to the ACL related to loans that were transferred to REO or repossessed assets totaled $1.2 million and $0.3 million for the three months ended March 31, 2020 and 2019, respectively. Write downs and net (gains) loss on sale of foreclosed/repossessed assets charged to non-interest expense totaled $0.4 million and $0.1 million for the same periods. (3) A fair value adjustment totaling $3.0 million was recorded for the three months ended March 31, 2020. (4) Represents the recorded investment in impaired loans with a related ACL measured in accordance with applicable accounting guidance. The provision for credit losses on impaired loans totaled $0.6 million for the three months ended March 31, 2019.
Carrying Amounts and Estimated Fair Values of Financial Instruments	The following tables summarize the carrying amounts, estimated fair values and placement in the fair value hierarchy of People’s United’s financial instruments that are not measured at fair value either on a recurring or non-recurring basis: Carrying Amount Estimated Fair Value Measurements Using As of March 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Cash and due from banks $ 507.6 $ 507.6 $ — $ — $ 507.6 Short-term investments 744.3 — 744.3 — 744.3 Debt securities held-to-maturity, net 3,861.5 — 4,063.7 1.5 4,065.2 FHLB and FRB stock 407.2 — 407.2 — 407.2 Total loans, net (1) 43,927.1 — 9,999.3 34,597.9 44,597.2 Financial liabilities: Time deposits 8,840.2 — 8,891.5 — 8,891.5 Other deposits 35,900.9 — 35,900.9 — 35,900.9 FHLB advances 4,489.7 — 4,490.7 — 4,490.7 Federal funds purchased 1,120.0 — 1,120.0 — 1,120.0 Customer repurchase agreements 301.1 — 301.1 — 301.1 Notes and debentures 1,012.6 — 995.8 — 995.8 Carrying Amount Estimated Fair Value Measurements Using As of December 31, 2019 (in millions) Level 1 Level 2 Level 3 Total Financial assets: Cash and due from banks $ 484.2 $ 484.2 $ — $ — $ 484.2 Short-term investments 316.8 — 316.8 — 316.8 Debt securities held-to-maturity 3,869.2 — 4,018.5 1.5 4,020.0 FHLB and FRB stock 341.1 — 341.1 — 341.1 Total loans, net (1) 43,287.6 — 10,072.1 33,282.9 43,355.0 Financial liabilities: Time deposits 9,205.5 — 9,218.1 — 9,218.1 Other deposits 34,384.0 — 34,384.0 — 34,384.0 FHLB advances 3,125.4 — 3,125.5 — 3,125.5 Federal funds purchased 1,620.0 — 1,620.0 — 1,620.0 Customer repurchase agreements 409.1 — 409.1 — 409.1 Other borrowings — 11.0 — 11.0 Notes and debentures 993.1 — 1,021.3 — 1,021.3 (1) Excludes collateral dependent loans totaling $15.2 million at March 31, 2020 and impaired loans totaling $61.9 million measured at fair value on a non-recurring basis at December 31, 2019.

Derivative Financial Instrume_2

Derivative Financial Instruments and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts and Fair Values of Derivatives Outstanding	The table below provides a summary of the notional amounts and fair values (presented on a gross basis) of derivatives outstanding: Fair Values (1) Notional Amounts Assets Liabilities (in millions) Type of Hedge March 31, Dec 31, March 31, Dec 31, 2019 March 31, Dec 31, 2019 Derivatives Not Designated as Hedging Interest rate swaps: Commercial customers N/A $ 9,207.6 $ 8,847.7 $ 905.4 $ 320.5 $ — $ 13.9 Institutional counterparties N/A 9,211.4 8,851.8 27.5 17.1 184.5 78.2 Interest rate caps: Commercial customers N/A 253.4 246.0 3.6 1.6 — 0.1 Institutional counterparties N/A 253.4 246.0 — 0.1 3.6 1.6 Risk participation agreements N/A 910.3 882.8 — — 0.5 0.1 Foreign exchange contracts N/A 237.7 180.4 8.6 1.2 9.2 1.8 Forward commitments to sell N/A 77.7 23.3 0.6 0.5 — — Interest rate-lock commitments on N/A 53.8 33.6 — — 0.7 0.5 Total 945.7 341.0 198.5 96.2 Derivatives Designated as Hedging Interest rate swaps: FHLB advances Cash flow 550.0 — — — — — Subordinated notes Fair value 375.0 375.0 — — — — Loans Cash flow 210.0 210.0 — — — — Total — — — — Total fair value of derivatives $ 945.7 $ 341.0 $ 198.5 $ 96.2 (1) Assets are recorded in other assets and liabilities are recorded in other liabilities.
Impact of Derivatives on Pre-Tax Income and Accumulated Other Comprehensive Loss	The following table summarizes the impact of People’s United’s derivatives on pre-tax income and AOCL: Type of Hedge Amount of Pre-Tax Gain (Loss) Recognized in Earnings (1) Amount of Pre-Tax Gain (Loss) Recognized in AOCL Three months ended March 31 (in millions) 2020 2019 2020 2019 Derivatives Not Designated as Hedging Interest rate swaps: Commercial customers N/A $ 613.6 $ 111.6 $ — $ — Institutional counterparties N/A (603.7) (108.8) — — Interest rate caps: Commercial customers N/A 2.0 1.1 — — Institutional counterparties N/A (2.0) (1.2) — — Foreign exchange contracts N/A 0.1 0.2 — — Risk participation agreements N/A (0.6) 0.1 — — Forward commitments to sell N/A 0.2 — — — Interest rate-lock commitments on N/A (0.2) — — — Total 9.4 3.0 — — Derivatives Designated as Hedging Interest rate swaps Fair value 0.4 (0.3) — — Interest rate swaps Cash flow — (0.4) 0.1 0.6 Interest rate locks (2) Cash flow — — — — Total 0.4 (0.7) 0.1 0.6 Total $ 9.8 $ 2.3 $ 0.1 $ 0.6 (1) Amounts recognized in earnings are recorded in interest income, interest expense or other non-interest income for derivatives designated as hedging instruments and in other non-interest income for derivatives not designated as hedging instruments. (2) Income totaled less than $0.1 million for both periods.

Balance Sheet Offsetting (Table

Balance Sheet Offsetting (Tables)	3 Months Ended
	Mar. 31, 2020
Offsetting [Abstract]
Summary of Gross Presentation, Financial Instruments that are Eligible for Offset Not Offset in Consolidated Statement of Condition	The following tables provide a gross presentation, the effects of offsetting, and a net presentation of the Company’s financial instruments that are eligible for offset in the Consolidated Statements of Condition. The collateral amounts in these tables are limited to the outstanding balances of the related asset or liability (after netting is applied) and, therefore, instances of overcollateralization are not presented. In the tables below, the Net Amount Presented of the derivative assets and liabilities can be reconciled to the fair value of the Company’s derivative financial instruments in Note 13. The Company’s derivative contracts with commercial customers and customer repurchase agreements are not subject to master netting arrangements and, therefore, have been excluded from the tables below. Gross Amount Recognized Gross Amount Offset Net Amount Presented Gross Amounts Not Offset Financial Instruments Net Amount As of March 31, 2020 (in millions) Collateral Financial assets: Interest rate swaps: Counterparty A $ — $ — $ — $ — $ — $ — Counterparty B — — — — — — Counterparty C — — — — — — Counterparty D — — — — — — Counterparty E 27.5 — 27.5 — — 27.5 Other counterparties — — — — — — Foreign exchange contracts 8.6 — 8.6 — — 8.6 Total $ 36.1 $ — $ 36.1 $ — $ — $ 36.1 Financial liabilities: Interest rate swaps: Counterparty A $ 6.4 $ — $ 6.4 $ — $ (6.4) $ — Counterparty B 9.9 — 9.9 — (9.9) — Counterparty C 64.2 — 64.2 — (64.2) — Counterparty D 24.6 — 24.6 — (24.6) — Counterparty E — — — — — — Other counterparties 83.0 — 83.0 — (83.0) — Foreign exchange contracts 9.2 — 9.2 — — 9.2 Total $ 197.3 $ — $ 197.3 $ — $ (188.1) $ 9.2 Gross Amount Recognized Gross Amount Offset Net Amount Presented Gross Amounts Not Offset Financial Instruments Net Amount As of December 31, 2019 (in millions) Collateral Financial assets: Interest rate swaps: Counterparty A $ 0.2 $ — $ 0.2 $ (0.2) $ — $ — Counterparty B 0.1 — 0.1 (0.1) — — Counterparty C 0.4 — 0.4 (0.4) — — Counterparty D 0.1 — 0.1 (0.1) — — Counterparty E 15.3 — 15.3 — — 15.3 Other counterparties 1.1 — 1.1 (1.1) — — Foreign exchange contracts 1.2 — 1.2 — — 1.2 Total $ 18.4 $ — $ 18.4 $ (1.9) $ — $ 16.5 Financial liabilities: Interest rate swaps: Counterparty A $ 2.3 $ — $ 2.3 $ (0.2) $ (2.1) $ — Counterparty B 5.5 — 5.5 (0.1) (5.4) — Counterparty C 28.2 — 28.2 (0.4) (27.8) — Counterparty D 10.9 — 10.9 (0.1) (10.8) — Counterparty E — — — — — — Other counterparties 32.9 — 32.9 (1.1) (31.8) — Foreign exchange contracts 1.8 — 1.8 — — 1.8 Total $ 81.6 $ — $ 81.6 $ (1.9) $ (77.9) $ 1.8
Summary of Collateral Swaps	The following tables show the extent to which assets and liabilities exchanged under resale and repurchase agreements have been offset in the Consolidated Statements of Condition. These agreements: (i) are entered into simultaneously with the same financial institution counterparty; (ii) have the same principal amounts and inception/maturity dates; and (iii) are subject to a master netting arrangement that contains a conditional right of offset upon default. At March 31, 2020 and December 31, 2019, the Company posted as collateral marketable securities with fair values of $454.2 million and $462.4 million, respectively, and, in turn, accepted as collateral marketable securities with fair values of $464.0 million and $457.5 million, respectively. As of March 31, 2020 (in millions) Gross Amount Recognized Gross Amount Offset Net Amount Presented Total resale agreements $ 450.0 $ (450.0) $ — Total repurchase agreements $ 450.0 $ (450.0) $ — As of December 31, 2019 (in millions) Gross Amount Recognized Gross Amount Offset Net Amount Presented Total resale agreements $ 450.0 $ (450.0) $ — Total repurchase agreements $ 450.0 $ (450.0) $ —

General (Detail)

General (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Affordable housing investments	$ 426.1		$ 383.9
Future contingent commitments	$ 164.1		$ 141.1
Amortization period	10 years
Income tax expense	$ 7	$ 5.4

Cash and Cash Equivalents and_3

Cash and Cash Equivalents and Securities - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020USD ($)Security	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Schedule of Investments [Line Items]
Accrued interest receivable, available-for-sale	$ 11,400,000
Accrued interest receivable, held-to-maturity	32,000,000
Debt security available for sale with a fair value pledged with collateral for public deposits	2,460,000,000		$ 2,430,000,000
Debt security available for sale with a held-to-maturity pledged with collateral for public deposits	$ 1,620,000,000		1,470,000,000
Number of debt securities owned | Security	272
Debt securities with unrealized losses	$ 100,000		6,900,000
Number of debt securities classified as available-for-sale | Security	2
Available for sale securities unrealized losses	$ 100,000		6,900,000
Held to maturity securities gross unrealized losses	2,800,000		700,000
Other-than-temporary impairment losses recognized in earnings	0	$ 0
Debt securities, allowance for credit loss	1,900,000
Debt securities, held-to-maturity nonaccrual	0
Unrealized (losses) gains due to change in fair value of equity securities	(1,400,000)	$ 200,000
Impairment of investments	$ 0
Federal Reserve Bank stock percentage	6.00%
Federal Reserve Bank of New York
Schedule of Investments [Line Items]
Interest-bearing deposits	$ 525,600,000		$ 219,400,000
Investment interest rate	0.10%		1.55%
Acquired shares of capital stock	$ 227,800,000		$ 203,800,000
FHLB of New York
Schedule of Investments [Line Items]
Acquired shares of capital stock	700,000		700,000
FHLB of Boston
Schedule of Investments [Line Items]
Acquired shares of capital stock	178,700,000		136,600,000
GSE mortgage-backed securities
Schedule of Investments [Line Items]
Debt securities with unrealized losses	100,000		4,100,000
Available for sale securities unrealized losses	100,000		4,100,000
Held to maturity securities gross unrealized losses	$ 0		300,000
Available for sale securities average maturity period	27 years
Debt securities, allowance for credit loss	$ 0
State and municipal
Schedule of Investments [Line Items]
Held to maturity securities gross unrealized losses	1,500,000		400,000
Debt securities, allowance for credit loss	100,000
Corporate
Schedule of Investments [Line Items]
Held to maturity securities gross unrealized losses	1,300,000		$ 0
Debt securities, allowance for credit loss	$ 1,800,000

Cash and Cash Equivalents and_4

Cash and Cash Equivalents and Securities - Available-for-Sale and Held-to-Maturity Debt Securities Gains (Losses) (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt securities available-for-sale:
Amortized Cost	$ 4,156.4	$ 3,545.8
Allowance for Credit Losses	0
Gross Unrealized Gains	120.3	25.4
Gross Unrealized Losses	(0.1)	(6.9)
Fair Value	4,276.6	3,564.3
Debt securities held-to-maturity:
Amortized Cost	3,863.4	3,869.2
Allowance for Credit Losses	1.9
Gross Unrealized Gains	202.7	151.5
Gross Unrealized Losses	(2.8)	(0.7)
Fair Value	4,065.2	4,020
U.S. Treasury and agency
Debt securities available-for-sale:
Amortized Cost	731.3	689.5
Allowance for Credit Losses	0
Gross Unrealized Gains	15.9	0.4
Gross Unrealized Losses	0	(2.8)
Fair Value	747.2	687.1
Debt securities held-to-maturity:
Amortized Cost	0
Fair Value	0
GSE mortgage-backed securities
Debt securities available-for-sale:
Amortized Cost	3,425.1	2,856.3
Allowance for Credit Losses	0
Gross Unrealized Gains	104.4	25
Gross Unrealized Losses	(0.1)	(4.1)
Fair Value	3,529.4	2,877.2
Debt securities held-to-maturity:
Amortized Cost	1,190.8	1,271.4
Allowance for Credit Losses	0
Gross Unrealized Gains	49.7	8
Gross Unrealized Losses	0	(0.3)
Fair Value	1,240.5	1,279.1
State and municipal
Debt securities available-for-sale:
Amortized Cost	0
Fair Value	0
Debt securities held-to-maturity:
Amortized Cost	2,574.9	2,503.9
Allowance for Credit Losses	0.1
Gross Unrealized Gains	151.4	142
Gross Unrealized Losses	(1.5)	(0.4)
Fair Value	2,724.9	2,645.5
Corporate
Debt securities available-for-sale:
Amortized Cost	0
Fair Value	0
Debt securities held-to-maturity:
Amortized Cost	96.2	92.4
Allowance for Credit Losses	1.8
Gross Unrealized Gains	1.6	1.5
Gross Unrealized Losses	(1.3)	0
Fair Value	98.3	93.9
Other
Debt securities available-for-sale:
Amortized Cost	0
Fair Value	0
Debt securities held-to-maturity:
Amortized Cost	1.5	1.5
Allowance for Credit Losses	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 1.5	$ 1.5

Cash and Cash Equivalents and_5

Cash and Cash Equivalents and Securities - Debt Securities Held-to-maturity Credit Quality (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Debt securities held-to-maturity	$ 3,863.4	$ 3,869.2
Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	3,858
Non-Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	5.4
State and municipal
Schedule of Investments [Line Items]
Debt securities held-to-maturity	2,574.9	2,503.9
State and municipal | Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	2,574.5
State and municipal | Non-Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	0.4
GSE mortgage-backed securities
Schedule of Investments [Line Items]
Debt securities held-to-maturity	1,190.8	1,271.4
GSE mortgage-backed securities | Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	1,190.8
GSE mortgage-backed securities | Non-Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	0
Corporate
Schedule of Investments [Line Items]
Debt securities held-to-maturity	96.2	92.4
Corporate | Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	91.2
Corporate | Non-Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	5
Other
Schedule of Investments [Line Items]
Debt securities held-to-maturity	1.5	$ 1.5
Other | Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	1.5
Other | Non-Investment Grade
Schedule of Investments [Line Items]
Debt securities held-to-maturity	$ 0

Cash and Cash Equivalents and_6

Cash and Cash Equivalents and Securities - Continuous Unrealized Loss Positions (Detail) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Available-for-sale, Fair Value
Less Than 12 Months	$ 10,900,000	$ 746,400,000
12 Months Or Longer	0	871,700,000
Total	10,900,000	1,618,100,000
Available-for-sale, Unrealized Losses
Less Than 12 Months	(100,000)	(3,500,000)
12 Months Or Longer	0	(3,400,000)
Total	(100,000)	(6,900,000)
Held-to-maturity, Fair Value
Less Than 12 Months		137,400,000
12 Months Or Longer		29,100,000
Total		166,500,000
Held-to-maturity, Unrealized Loss
Less Than 12 Months		(500,000)
12 Months Or Longer		(200,000)
Total		(700,000)
Maximum
Available-for-sale, Unrealized Losses
Total	(100,000)
U.S. Treasury and agency
Available-for-sale, Fair Value
Less Than 12 Months		181,000,000
12 Months Or Longer		362,400,000
Total		543,400,000
Available-for-sale, Unrealized Losses
Less Than 12 Months		(400,000)
12 Months Or Longer		(2,400,000)
Total		(2,800,000)
GSE mortgage-backed securities
Available-for-sale, Fair Value
Less Than 12 Months	10,900,000	565,400,000
12 Months Or Longer	0	509,300,000
Total	10,900,000	1,074,700,000
Available-for-sale, Unrealized Losses
Less Than 12 Months	(100,000)	(3,100,000)
12 Months Or Longer	0	(1,000,000)
Total	$ (100,000)	(4,100,000)
Held-to-maturity, Fair Value
Less Than 12 Months		100,900,000
12 Months Or Longer		9,100,000
Total		110,000,000
Held-to-maturity, Unrealized Loss
Less Than 12 Months		(300,000)
12 Months Or Longer		0
Total		(300,000)
State and municipal
Held-to-maturity, Fair Value
Less Than 12 Months		33,000,000
12 Months Or Longer		11,400,000
Total		44,400,000
Held-to-maturity, Unrealized Loss
Less Than 12 Months		(200,000)
12 Months Or Longer		(200,000)
Total		(400,000)
Corporate
Held-to-maturity, Fair Value
Less Than 12 Months		3,500,000
12 Months Or Longer		8,600,000
Total		12,100,000
Held-to-maturity, Unrealized Loss
Less Than 12 Months		0
12 Months Or Longer		0
Total		$ 0

Cash and Cash Equivalents and_7

Cash and Cash Equivalents and Securities - Summary of Amortized Cost and Fair Value to Contractual Maturity (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule of Investments [Line Items]
Available for Sale, Amortized Cost, Within 1 year	$ 200.8
Available for Sale, Amortized Cost, After 1 but within 5 years	613.7
Available for Sale, Amortized Cost, After 5 but within 10 years	880.8
Available for Sale, Amortized Cost, After 10 years	2,461.1
Amortized Cost	4,156.4	$ 3,545.8
Available for Sale, Fair Value, Within 1 year	201.4
Available for Sale, Fair Value, After 1 but within 5 years	633.1
Available for Sale, Fair Value, After 5 but within 10 years	918.9
Available for Sale, Fair Value, After 10 years	2,523.2
Available for Sale, Fair Value, Total	4,276.6	3,564.3
Held to Maturity, Amortized Cost, Within 1 year	16.5
Held to Maturity, Amortized Cost, After 1 but within 5 years	1,089.2
Held to Maturity, Amortized Cost, After 5 but within 10 years	637.6
Held to Maturity, Amortized Cost, After 10 years	2,120.1
Amortized Cost	3,863.4	3,869.2
Held to Maturity, Fair Value, Within 1 year	16.5
Held to Maturity, Fair Value, After 1 but within 5 years	1,136.1
Held to Maturity, Fair Value, After 5 but within 10 years	672.6
Held to Maturity, Fair Value, After 10 years	2,240
Held to Maturity, Fair Value, Total	4,065.2	4,020
U.S. Treasury and agency
Schedule of Investments [Line Items]
Available for Sale, Amortized Cost, Within 1 year	200.8
Available for Sale, Amortized Cost, After 1 but within 5 years	530.5
Amortized Cost	731.3	689.5
Available for Sale, Fair Value, Within 1 year	201.4
Available for Sale, Fair Value, After 1 but within 5 years	545.8
Available for Sale, Fair Value, Total	747.2	687.1
Held to Maturity, Amortized Cost, Within 1 year	0
Held to Maturity, Amortized Cost, After 1 but within 5 years	0
Amortized Cost	0
Held to Maturity, Fair Value, Within 1 year	0
Held to Maturity, Fair Value, After 1 but within 5 years	0
Held to Maturity, Fair Value, Total	0
GSE mortgage-backed securities
Schedule of Investments [Line Items]
Available for Sale, Amortized Cost, After 1 but within 5 years	83.2
Available for Sale, Amortized Cost, After 5 but within 10 years	880.8
Available for Sale, Amortized Cost, After 10 years	2,461.1
Amortized Cost	3,425.1	2,856.3
Available for Sale, Fair Value, After 1 but within 5 years	87.3
Available for Sale, Fair Value, After 5 but within 10 years	918.9
Available for Sale, Fair Value, After 10 years	2,523.2
Available for Sale, Fair Value, Total	3,529.4	2,877.2
Held to Maturity, Amortized Cost, After 1 but within 5 years	841.2
Held to Maturity, Amortized Cost, After 5 but within 10 years	77.5
Held to Maturity, Amortized Cost, After 10 years	272.1
Amortized Cost	1,190.8	1,271.4
Held to Maturity, Fair Value, After 1 but within 5 years	879.3
Held to Maturity, Fair Value, After 5 but within 10 years	82.4
Held to Maturity, Fair Value, After 10 years	278.8
Held to Maturity, Fair Value, Total	1,240.5	1,279.1
State and municipal
Schedule of Investments [Line Items]
Available for Sale, Amortized Cost, Within 1 year	0
Available for Sale, Amortized Cost, After 1 but within 5 years	0
Available for Sale, Amortized Cost, After 5 but within 10 years	0
Available for Sale, Amortized Cost, After 10 years	0
Amortized Cost	0
Available for Sale, Fair Value, Within 1 year	0
Available for Sale, Fair Value, After 1 but within 5 years	0
Available for Sale, Fair Value, After 5 but within 10 years	0
Available for Sale, Fair Value, After 10 years	0
Available for Sale, Fair Value, Total	0
Held to Maturity, Amortized Cost, Within 1 year	10
Held to Maturity, Amortized Cost, After 1 but within 5 years	245.5
Held to Maturity, Amortized Cost, After 5 but within 10 years	471.4
Held to Maturity, Amortized Cost, After 10 years	1,848
Amortized Cost	2,574.9	2,503.9
Held to Maturity, Fair Value, Within 1 year	10
Held to Maturity, Fair Value, After 1 but within 5 years	254.3
Held to Maturity, Fair Value, After 5 but within 10 years	499.4
Held to Maturity, Fair Value, After 10 years	1,961.2
Held to Maturity, Fair Value, Total	2,724.9	2,645.5
Corporate
Schedule of Investments [Line Items]
Available for Sale, Amortized Cost, Within 1 year	0
Available for Sale, Amortized Cost, After 1 but within 5 years	0
Available for Sale, Amortized Cost, After 5 but within 10 years	0
Amortized Cost	0
Available for Sale, Fair Value, Within 1 year	0
Available for Sale, Fair Value, After 1 but within 5 years	0
Available for Sale, Fair Value, After 5 but within 10 years	0
Available for Sale, Fair Value, Total	0
Held to Maturity, Amortized Cost, Within 1 year	5
Held to Maturity, Amortized Cost, After 1 but within 5 years	2.5
Held to Maturity, Amortized Cost, After 5 but within 10 years	88.7
Amortized Cost	96.2	92.4
Held to Maturity, Fair Value, Within 1 year	5
Held to Maturity, Fair Value, After 1 but within 5 years	2.5
Held to Maturity, Fair Value, After 5 but within 10 years	90.8
Held to Maturity, Fair Value, Total	98.3	93.9
Other
Schedule of Investments [Line Items]
Available for Sale, Amortized Cost, Within 1 year	0
Amortized Cost	0
Available for Sale, Fair Value, Within 1 year	0
Available for Sale, Fair Value, Total	0
Held to Maturity, Amortized Cost, Within 1 year	1.5
Amortized Cost	1.5	1.5
Held to Maturity, Fair Value, Within 1 year	1.5
Held to Maturity, Fair Value, Total	$ 1.5	$ 1.5

Loans - Additional Information

Loans - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020USD ($)RatingSegment	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of segments | Segment	2
Net deferred loan costs	$ 73,500,000		$ 87,500,000
Nonaccrual interest income	500,000
Loans past due and accruing	0		0
Allowance for loan losses	$ 341,700,000	$ 240,900,000	246,600,000	$ 240,400,000
Temporary reduction of interest rate for TDRs, basis points	2.00%
Collateral values/LTV ratios, minimum	70.00%
Borrower credit scores, minimum | Rating	680
Repossessed assets	$ 4,600,000		4,200,000
Loans held-for-sale	19,200,000		511,300,000
Gain (Loss) on Sale of Loans and Leases	15,500,000	400,000
Nonrecurring
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	19,200,000
Other Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable accrued interest	111,900,000
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Early non-performing loans	24,200,000		27,600,000
Real estate owned	7,300,000		7,300,000
Commercial real estate | Nonrecurring
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale			157,900,000
Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Early non-performing loans	33,600,000		23,000,000
Equipment financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Early non-performing loans	19,400,000		26,200,000
MWABL
Accounts, Notes, Loans and Financing Receivable [Line Items]
Early non-performing loans	1,100,000
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate owned	9,500,000		11,900,000
Residential mortgage | Nonrecurring
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale	19,200,000		19,700,000
Other consumer | Nonrecurring
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale			333,700,000
Other consumer | Nonrecurring | United Financial Bancorp, Inc
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale			333,700,000
Commercial Loan | Nonrecurring | United Financial Bancorp, Inc
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held-for-sale			157,900,000
Consumer And Commercial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain (Loss) on Sale of Loans and Leases	16,900,000
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	211,800,000	209,000,000	217,900,000	209,500,000
Commercial | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	28,100,000
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	129,900,000	31,900,000	28,700,000	$ 30,900,000
Retail | Collateral Pledged
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 29,200,000
Maximum | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Duration of extension for payment deferral on TDRs, years	2 years
Maximum | Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Duration of extension for payment deferral on TDRs, years	5 years
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan agreement	6 months
Troubled Debt Restructurings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in originated loans classified as TDRs	$ 178,900,000		177,000,000
Allowance for loan losses	13,100,000		4,300,000
Interest income recognized	1,300,000	$ 1,600,000
Foreclosure or Bankruptcy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Early non-performing loans	$ 38,000,000		$ 36,800,000

Loans - Summary of Loans by Loa

Loans - Summary of Loans by Loan Portfolio Segment and Class (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 44,284	$ 43,596.1
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	31,710	30,714.3
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	14,651.6	14,762.3
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	9,097.7	8,693.2
Commercial | Equipment financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	5,012.7	4,910.4
Commercial | MWABL
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	2,948	2,348.4
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	12,574	12,881.8
Retail | Adjustable-rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	6,825.2	7,064.8
Retail | Fixed-rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	3,256.7	3,253.3
Retail | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	10,081.9	10,318.1
Retail | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	2,349.9	2,406.5
Retail | Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	142.2	157.2
Retail | Home equity and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 2,492.1	$ 2,563.7

Loans - Summary of Aging Inform

Loans - Summary of Aging Information by Class of Loan (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 43,881.4	$ 43,273.2
Total Past Due	402.6	322.9
Total loans	44,284	43,596.1
30-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	277.3	209.8
90 Days or More
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	125.3	113.1
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	31,436.6	30,515.5
Total Past Due	273.4	198.8
Total loans	31,710	30,714.3
Commercial | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	14,580	14,713.8
Total Past Due	71.6	48.5
Total loans	14,651.6	14,762.3
Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	9,055.4
Total Past Due	42.3
Total loans	9,097.7	8,693.2
Commercial | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current		11,010.7
Total Past Due		30.9
Total loans	12,045.7	11,041.6
Commercial | Equipment financing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	4,853.2	4,791
Total Past Due	159.5	119.4
Total loans	5,012.7	4,910.4
Commercial | MWABL
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,948
Total Past Due	0
Total loans	2,948	2,348.4
Commercial | 30-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	198.9	133.3
Commercial | 30-89 Days | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	43.7	22.3
Commercial | 30-89 Days | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	18.8
Commercial | 30-89 Days | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		13.1
Commercial | 30-89 Days | Equipment financing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	136.4	97.9
Commercial | 30-89 Days | MWABL
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Commercial | 90 Days or More
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	74.5	65.5
Commercial | 90 Days or More | Commercial real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	27.9	26.2
Commercial | 90 Days or More | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	23.5
Commercial | 90 Days or More | Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due		17.8
Commercial | 90 Days or More | Equipment financing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	23.1	21.5
Commercial | 90 Days or More | MWABL
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	12,444.8	12,757.7
Total Past Due	129.2	124.1
Total loans	12,574	12,881.8
Retail | Residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	9,978.3	10,215.9
Total Past Due	103.6	102.2
Total loans	10,081.9	10,318.1
Retail | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	2,325.3	2,385.7
Total Past Due	24.6	20.8
Total loans	2,349.9	2,406.5
Retail | Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	141.2	156.1
Total Past Due	1	1.1
Total loans	142.2	157.2
Retail | 30-89 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	78.4	76.5
Retail | 30-89 Days | Residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	64.2	65.5
Retail | 30-89 Days | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	13.3	9.9
Retail | 30-89 Days | Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0.9	1.1
Retail | 90 Days or More
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	50.8	47.6
Retail | 90 Days or More | Residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	39.4	36.7
Retail | 90 Days or More | Home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	11.3	10.9
Retail | 90 Days or More | Other consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 0.1	$ 0

Loans - Summarized Recorded Inv

Loans - Summarized Recorded Investments, by Class of Loan, in Originated Non-Performing Loans (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	$ 1.2
2019	31.1
2018	19.5
2017	15.2
2016	12.9
Prior	109.5
Revolving Loans	51
Total	240.4	$ 224.1
Non-Accrual Loans With No ACL	42
Government guarantees	1.2	1.3
Foreclosure
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	25.4	17
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	1.2
2019	29.8
2018	16.1
2017	12.9
2016	11.3
Prior	47.4
Revolving Loans	32.9
Total	151.6	140
Non-Accrual Loans With No ACL	14.4
Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0
2018	3.4
2017	2.3
2016	1.6
Prior	62.1
Revolving Loans	18.1
Total	88.8	84.1
Non-Accrual Loans With No ACL	27.6
Commercial real estate | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0
2018	2.1
2017	2.1
2016	4.9
Prior	28
Revolving Loans	0.1
Total	53.5	53.8
Non-Accrual Loans With No ACL	5.3
Commercial and industrial | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0.3
2018	0.6
2017	2.2
2016	2.1
Prior	14.7
Revolving Loans	31.7
Total	54.5	38.5
Non-Accrual Loans With No ACL	7.2
Equipment financing | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0.9
2018	13.4
2017	8.6
2016	4.3
Prior	4.7
Revolving Loans	0
Total	42.5	47.7
Non-Accrual Loans With No ACL	1.9
MWABL | Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0
2018	0
2017	0
2016	0
Prior	0
Revolving Loans	1.1
Total	1.1	0
Non-Accrual Loans With No ACL	0
Residential mortgage | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0
2018	3.2
2017	2.3
2016	1.4
Prior	58.4
Revolving Loans	0
Total	66.6	63.3
Non-Accrual Loans With No ACL	22
Home equity | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0
2018	0.1
2017	0
2016	0.2
Prior	3.7
Revolving Loans	18.1
Total	22.1	20.8
Non-Accrual Loans With No ACL	5.6
Other consumer | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
2020	0
2018	0.1
2017	0
2016	0
Prior	0
Revolving Loans	0
Total	0.1	$ 0
Non-Accrual Loans With No ACL	$ 0

Loans - Summary of Recorded Inv

Loans - Summary of Recorded Investments in TDRs by Class of Loan (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)contract	Mar. 31, 2019USD ($)contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	54	62
Pre-Modification Outstanding Recorded Investment	$ 24.1	$ 19.4
Post-Modification Outstanding Recorded Investment	$ 24.1	$ 19.4
Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	24	20
Pre-Modification Outstanding Recorded Investment	$ 15.8	$ 11.7
Post-Modification Outstanding Recorded Investment	$ 15.8	$ 11.7
Retail
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	30	42
Pre-Modification Outstanding Recorded Investment	$ 8.3	$ 7.7
Post-Modification Outstanding Recorded Investment	$ 8.3	$ 7.7
Commercial real estate | Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	5	2
Pre-Modification Outstanding Recorded Investment	$ 3.7	$ 3
Post-Modification Outstanding Recorded Investment	$ 3.7	$ 3
Commercial real estate | Commercial | Extended Maturity
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	4
Post-Modification Outstanding Recorded Investment	$ 3.2
Commercial real estate | Commercial | Payment Deferral
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract		2
Post-Modification Outstanding Recorded Investment	$ 0.5	$ 3
Commercial and industrial | Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	10	4
Pre-Modification Outstanding Recorded Investment	$ 9	$ 1.4
Post-Modification Outstanding Recorded Investment	$ 9	$ 1.4
Commercial and industrial | Commercial | Extended Maturity
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	5	4
Post-Modification Outstanding Recorded Investment	$ 7.4	$ 1.4
Commercial and industrial | Commercial | Payment Deferral
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1
Post-Modification Outstanding Recorded Investment	$ 0.3
Commercial and industrial | Commercial | Combination of Concessions
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	4
Post-Modification Outstanding Recorded Investment	$ 1.3
Equipment financing | Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	9	14
Pre-Modification Outstanding Recorded Investment	$ 3.1	$ 7.3
Post-Modification Outstanding Recorded Investment	$ 3.1	$ 7.3
Equipment financing | Commercial | Extended Maturity
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	8
Post-Modification Outstanding Recorded Investment	$ 1.2	$ 6.6
Equipment financing | Commercial | Payment Deferral
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	5	5
Post-Modification Outstanding Recorded Investment	$ 0.5	$ 0.5
Equipment financing | Commercial | Combination of Concessions
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	3	1
Post-Modification Outstanding Recorded Investment	$ 1.4	$ 0.2
MWABL | Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	$ 0
Residential mortgage | Retail
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	13	20
Pre-Modification Outstanding Recorded Investment	$ 6.2	$ 5.6
Post-Modification Outstanding Recorded Investment	$ 6.2	$ 5.6
Residential mortgage | Retail | Payment Deferral
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	9	5
Post-Modification Outstanding Recorded Investment	$ 5.5	$ 2.2
Residential mortgage | Retail | Combination of Concessions
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	6
Post-Modification Outstanding Recorded Investment	$ 0.1	$ 2.3
Residential mortgage | Retail | Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	3	9
Post-Modification Outstanding Recorded Investment	$ 0.6	$ 1.1
Home equity | Retail
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	17	22
Pre-Modification Outstanding Recorded Investment	$ 2.1	$ 2.1
Post-Modification Outstanding Recorded Investment	$ 2.1	$ 2.1
Home equity | Retail | Payment Deferral
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	3
Post-Modification Outstanding Recorded Investment	$ 0.1	$ 0.5
Home equity | Retail | Combination of Concessions
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	11	10
Post-Modification Outstanding Recorded Investment	$ 1.5	$ 1
Home equity | Retail | Bankruptcy
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	5	9
Post-Modification Outstanding Recorded Investment	$ 0.5	$ 0.6
Other consumer | Retail
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0

Loans - Summary of Recorded I_2

Loans - Summary of Recorded Investments in TDRs by Class of Loan, Subsequently Defaulted (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)contract	Mar. 31, 2019USD ($)contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	9	7
Recorded Investment as of Period End | $	$ 3.9	$ 4.6
Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	5	2
Recorded Investment as of Period End | $	$ 2.6	$ 2.9
Commercial | Commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0
Recorded Investment as of Period End | $	$ 0	$ 0
Commercial | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	0
Recorded Investment as of Period End | $	$ 0.1	$ 0
Commercial | Equipment financing
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	4	2
Recorded Investment as of Period End | $	$ 2.5	$ 2.9
Commercial | MWABL
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0
Recorded Investment as of Period End | $	$ 0	$ 0
Retail
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	4	5
Recorded Investment as of Period End | $	$ 1.3	$ 1.7
Retail | Residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	3	3
Recorded Investment as of Period End | $	$ 1.3	$ 1.3
Retail | Home equity
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	1	2
Recorded Investment as of Period End | $	$ 0	$ 0.4
Retail | Other consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts | contract	0	0
Recorded Investment as of Period End | $	$ 0	$ 0

Loans - Schedule of Commercial

Loans - Schedule of Commercial Loans By Risk Ratings (Details) - Commercial $ in Millions	Mar. 31, 2020USD ($)
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
2020	$ 337.6
2019	1,800.3
2018	1,844.7
2017	1,760.3
2016	1,629.2
Prior	6,893.5
Revolving Loans	386
Total	14,651.6
Commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
2020	335.3
2019	1,762.3
2018	1,730.4
2017	1,703.1
2016	1,584
Prior	6,615
Revolving Loans	380.7
Total	14,110.8
Commercial real estate | Special mention
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	8.7
2018	91.4
2017	28
2016	38.6
Prior	115.3
Revolving Loans	2.4
Total	284.4
Commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
2020	2.3
2019	29.3
2018	22.9
2017	29.2
2016	6.6
Prior	161.6
Revolving Loans	2.9
Total	254.8
Commercial real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	1.6
Revolving Loans	0
Total	1.6
Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
2020	676.9
2019	1,899.3
2018	1,094.6
2017	845.3
2016	688.9
Prior	2,120.6
Revolving Loans	1,772.1
Total	9,097.7
Commercial and industrial | Pass
Financing Receivable, Recorded Investment [Line Items]
2020	674.1
2019	1,876.3
2018	1,015.3
2017	801.6
2016	635.6
Prior	1,930.1
Revolving Loans	1,635
Total	8,568
Commercial and industrial | Special mention
Financing Receivable, Recorded Investment [Line Items]
2020	2.1
2019	11.5
2018	22.3
2017	6.1
2016	39.8
Prior	63.1
Revolving Loans	41.9
Total	186.8
Commercial and industrial | Substandard
Financing Receivable, Recorded Investment [Line Items]
2020	0.7
2019	11.5
2018	57
2017	37
2016	12.3
Prior	127.4
Revolving Loans	93.5
Total	339.4
Commercial and industrial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0.6
2016	1.2
Prior	0
Revolving Loans	1.7
Total	3.5
Equipment financing
Financing Receivable, Recorded Investment [Line Items]
2020	615.1
2019	2,037.9
2018	1,186.8
2017	655.1
2016	320.6
Prior	197.2
Revolving Loans	0
Total	5,012.7
Equipment financing | Pass
Financing Receivable, Recorded Investment [Line Items]
2020	556.4
2019	1,843
2018	1,068.9
2017	587.7
2016	303.1
Prior	164.3
Revolving Loans	0
Total	4,523.4
Equipment financing | Special mention
Financing Receivable, Recorded Investment [Line Items]
2020	13.5
2019	33.7
2018	16.1
2017	10.9
2016	4.4
Prior	1.7
Revolving Loans	0
Total	80.3
Equipment financing | Substandard
Financing Receivable, Recorded Investment [Line Items]
2020	45.2
2019	161.2
2018	101.8
2017	56.5
2016	13.1
Prior	31.2
Revolving Loans	0
Total	409
Equipment financing | Doubtful
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving Loans	0
Total	0
MWABL
Financing Receivable, Recorded Investment [Line Items]
2020	2.6
2019	18.1
2018	15
2017	8.5
2016	21.7
Prior	64.6
Revolving Loans	2,817.5
Total	2,948
MWABL | Pass
Financing Receivable, Recorded Investment [Line Items]
2020	2.6
2019	10.8
2018	15
2017	6.6
2016	21
Prior	62.7
Revolving Loans	2,697
Total	2,815.7
MWABL | Special mention
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	7.3
2018	0
2017	0
2016	0
Prior	0
Revolving Loans	68.6
Total	75.9
MWABL | Substandard
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	1.9
2016	0.7
Prior	1.9
Revolving Loans	51.9
Total	56.4
MWABL | Doubtful
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving Loans	0
Total	$ 0

Loans - Schedule of Retail Loan

Loans - Schedule of Retail Loans By Risk Ratings (Details) - Retail $ in Millions	Mar. 31, 2020USD ($)
Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
2020	$ 210.6
2019	1,120.7
2018	1,376.9
2017	1,642.5
2016	2,163.6
Prior	3,567.6
Revolving Loans	0
Total	10,081.9
Residential mortgage | Low risk
Financing Receivable, Recorded Investment [Line Items]
2020	51.5
2019	400.9
2018	423.9
2017	560.7
2016	1,130.5
Prior	1,937.1
Revolving Loans	0
Total	4,504.6
Residential mortgage | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
2020	132.7
2019	640
2018	835.4
2017	967.7
2016	928.3
Prior	1,335.1
Revolving Loans	0
Total	4,839.2
Residential mortgage | High risk
Financing Receivable, Recorded Investment [Line Items]
2020	26.4
2019	79.8
2018	117.6
2017	114.1
2016	104.8
Prior	295.4
Revolving Loans	0
Total	738.1
Home equity
Financing Receivable, Recorded Investment [Line Items]
2020	2.4
2019	43.2
2018	95.1
2017	74.1
2016	30.7
Prior	81.2
Revolving Loans	2,023.2
Total	2,349.9
Home equity | Low risk
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	31.7
Revolving Loans	335.2
Total	366.9
Home equity | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
2020	0.4
2019	15.3
2018	12.1
2017	6.1
2016	3.2
Prior	35.2
Revolving Loans	689.5
Total	761.8
Home equity | High risk
Financing Receivable, Recorded Investment [Line Items]
2020	2
2019	27.9
2018	83
2017	68
2016	27.5
Prior	14.3
Revolving Loans	998.5
Total	1,221.2
Other consumer
Financing Receivable, Recorded Investment [Line Items]
2020	4.9
2019	68.3
2018	49
2017	5.4
2016	1.5
Prior	13.1
Revolving Loans	0
Total	142.2
Other consumer | Low risk
Financing Receivable, Recorded Investment [Line Items]
2020	1.6
2019	10
2018	6.3
2017	1.5
2016	0.5
Prior	4.8
Revolving Loans	0
Total	24.7
Other consumer | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
2020	0
2019	0.1
2018	0.2
2017	0.1
2016	0.2
Prior	5.3
Revolving Loans	0
Total	5.9
Other consumer | High risk
Financing Receivable, Recorded Investment [Line Items]
2020	3.3
2019	58.2
2018	42.5
2017	3.8
2016	0.8
Prior	3
Revolving Loans	0
Total	$ 111.6

Loans - Summary of Credit Quali

Loans - Summary of Credit Quality Indicators by Class of Loan (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 44,284	$ 43,596.1
Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans	31,710	30,714.3
Retail
Financing Receivable, Recorded Investment [Line Items]
Loans	12,574	12,881.8
Originated | Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans		29,047.5
Originated | Commercial | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans		741.2
Originated | Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans		918.8
Originated | Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans		6.8
Originated | Retail | Low risk
Financing Receivable, Recorded Investment [Line Items]
Loans		5,182.2
Originated | Retail | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
Loans		5,512.7
Originated | Retail | High risk
Financing Receivable, Recorded Investment [Line Items]
Loans		2,186.9
Commercial real estate | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans	14,651.6	14,762.3
Commercial real estate | Originated | Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans		14,222.3
Commercial real estate | Originated | Commercial | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans		334.3
Commercial real estate | Originated | Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans		202.6
Commercial real estate | Originated | Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans		3.1
Commercial and industrial | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans	9,097.7	8,693.2
Commercial and industrial | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans	12,045.7	11,041.6
Commercial and industrial | Originated | Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans		10,391.7
Commercial and industrial | Originated | Commercial | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans		330.4
Commercial and industrial | Originated | Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans		315.8
Commercial and industrial | Originated | Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans		3.7
Equipment financing | Commercial
Financing Receivable, Recorded Investment [Line Items]
Loans	5,012.7	4,910.4
Equipment financing | Originated | Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Loans		4,433.5
Equipment financing | Originated | Commercial | Special mention
Financing Receivable, Recorded Investment [Line Items]
Loans		76.5
Equipment financing | Originated | Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans		400.4
Equipment financing | Originated | Commercial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Loans		0
Residential mortgage | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans	10,081.9	10,318.1
Residential mortgage | Originated | Retail | Low risk
Financing Receivable, Recorded Investment [Line Items]
Loans		4,410
Residential mortgage | Originated | Retail | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
Loans		4,958.3
Residential mortgage | Originated | Retail | High risk
Financing Receivable, Recorded Investment [Line Items]
Loans		949.8
Home equity | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans	2,349.9	2,406.5
Home equity | Originated | Retail | Low risk
Financing Receivable, Recorded Investment [Line Items]
Loans		747.3
Home equity | Originated | Retail | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
Loans		548.5
Home equity | Originated | Retail | High risk
Financing Receivable, Recorded Investment [Line Items]
Loans		1,110.7
Other consumer | Retail
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 142.2	157.2
Other consumer | Originated | Retail | Low risk
Financing Receivable, Recorded Investment [Line Items]
Loans		24.9
Other consumer | Originated | Retail | Moderate risk
Financing Receivable, Recorded Investment [Line Items]
Loans		5.9
Other consumer | Originated | Retail | High risk
Financing Receivable, Recorded Investment [Line Items]
Loans		$ 126.4

Allowance For Credit Losses (De

Allowance For Credit Losses (Details) $ in Millions	Mar. 31, 2020USD ($)
Allowance for Credit Loss [Abstract]
Originated Loans Individually Evaluated for Impairment, Allowance	$ 8.9

Schedule of Allowance For Credi

Schedule of Allowance For Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	$ 246.6	$ 240.4
Charge-offs	(12.6)	(7.5)
Recoveries	2	2.4
Net loan charge-offs	(10.6)	(5.1)
Provision for credit losses	33.5	5.6
Balance at end of period	341.7	240.9
Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	217.9	209.5
Charge-offs	(9.7)	(6.4)
Recoveries	1.4	1.4
Net loan charge-offs	(8.3)	(5)
Provision for credit losses	19.5	4.5
Balance at end of period	211.8	209
Retail
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	28.7	30.9
Charge-offs	(2.9)	(1.1)
Recoveries	0.6	1
Net loan charge-offs	(2.3)	(0.1)
Provision for credit losses	14	1.1
Balance at end of period	129.9	$ 31.9
Cumulative Effect, Period Of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	72.2
Cumulative Effect, Period Of Adoption, Adjustment | Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	(17.3)
Cumulative Effect, Period Of Adoption, Adjustment | Retail
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	$ 89.5

Allowance For Credit Losses - O

Allowance For Credit Losses - Off-Balance Sheet (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	$ 5.6
Provision charged (credited) to income	0.6
Balance at end of period	20.7
Cumulative Effect, Period Of Adoption, Adjustment
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	14.5
Cumulative Effect, Period Of Adoption, Adjusted Balance
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	$ 20.1

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Leases [Abstract]
Total lease liabilities	$ 307.5	$ 307.9	$ 268.8
Operating leases	$ 275.9	$ 276.6	$ 248.5

Leases - Net Investment in Leas

Leases - Net Investment in Lease Financing Receivables (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Lease payments receivable	$ 1,451.7	$ 1,417.1
Estimated residual value of leased assets	128.7	128
Total	1,580.4	1,545.1
Plus: Deferred origination costs	13	13.4
Less: Unearned income	(158.5)	(156.9)
Total net investment in lease financing receivables	$ 1,434.9	$ 1,401.6

Leases - Contractual Maturities

Leases - Contractual Maturities of Lease Financing Receivables (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Leases [Abstract]
2020	$ 408.6
2021	448.4
2022	340.8
2023	208.7
2024	117.7
Later years	56.2
Total	$ 1,580.4	$ 1,545.1

Leases - Schedule of Lease Inco

Leases - Schedule of Lease Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
Lease financing receivables	$ 17.6	$ 15.5
Operating leases	12.6	12.7
Total lease income	$ 30.2	$ 28.2

Leases - Cost and Supplemental

Leases - Cost and Supplemental Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Jan. 01, 2019
Leases [Abstract]
Operating lease cost	$ 16.7	$ 15.3
Variable lease cost	3.1	2.3
Finance lease cost	0.1	0
Sublease income	(0.5)	(0.4)
Net lease cost	19.4	17.2
Lease ROU assets:
Operating leases	275.9		$ 276.6	$ 248.5
Finance leases	2.5		2.6
Lease liabilities:
Operating leases	307.5		307.9	$ 268.8
Total lease liabilities	$ 5.2		$ 5.3
Weighted-average discount rate:
Operating leases	3.12%		3.13%
Finance leases	2.58%		2.58%
Weighted-average remaining lease term (in years):
Operating leases	7 years 9 months 18 days		7 years 8 months 12 days
Finance leases	11 years 10 months 24 days		12 years 2 months 12 days
Cash payments included in the measurement of lease liabilities:
Reported in operating cash from operating leases	$ 17.1	15.4
Reported in financing cash from finance leases	0.1	0
ROU assets obtained in exchange for lessee:
Operating lease liabilities	14.3	10.3
Finance lease liabilities	$ 0	$ 0

Leases - Contractual Maturiti_2

Leases - Contractual Maturities of Lease Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Operating Leases
2020	$ 50.4
2021	65.3
2022	47.7
2023	36
2024	30
Later years	121
Total lease payments	350.4
Less: Interest	(42.9)
Total lease liabilities	307.5	$ 307.9	$ 268.8
Finance Leases
2020	0.4
2021	0.5
2022	0.5
2023	0.5
2024	0.5
Later years	3.7
Total lease payments	6.1
Less: Interest	(0.9)
Total lease liabilities	$ 5.2	$ 5.3

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Schedule Of Stockholders Equity [Line Items]
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock par value, per share (USD per share)	$ 0.01	$ 0.01
Preferred stock, shares outstanding (in shares)	10,000,000	10,000,000
Common stock, shares authorized (in shares)	1,950,000,000	1,950,000,000
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares issued (in shares)	533,500,000	532,800,000
Common stock purchased (in shares)	109,000,000	89,200,000
Number of shares authorized for repurchase (in shares)		20,000,000
Treasury stock shares acquired (in shares)	19,800,000
Treasury stock acquired	$ 304.4
People's United Financial, Inc.
Schedule Of Stockholders Equity [Line Items]
Preferred stock, shares authorized (in shares)	50,000,000	50,000,000
Preferred stock par value, per share (USD per share)	$ 0.01	$ 0.01
Preferred stock, shares outstanding (in shares)	10,000,000	10,000,000
Common stock, shares authorized (in shares)	1,950,000,000	1,950,000,000
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, shares issued (in shares)	533,500,000	532,800,000
Repurchases Authorized by Board of Directors
Schedule Of Stockholders Equity [Line Items]
Common stock purchased (in shares)	106,400,000	86,600,000
2007 Recognition and Retention Plan
Schedule Of Stockholders Equity [Line Items]
Common stock purchased (in shares)	2,600,000
2014 Long-Term Incentive Plan | 2007 Recognition and Retention Plan
Schedule Of Stockholders Equity [Line Items]
Additional awards under RRP (in shares)	0

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 7,947.2	$ 6,533.9
Other comprehensive income before reclassifications	71.6	29.5
Amounts reclassified from AOCL	2.6	2.7
Current period other comprehensive income	74.2	32.2
Ending Balance	7,725.5	6,621.2
Pension and Other Postretirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(176.2)	(192.5)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from AOCL	1.6	1.8
Current period other comprehensive income	1.6	1.8
Ending Balance	(174.6)	(190.7)
Net Unrealized Gains (Losses) on Debt Securities Available-for-Sale
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	20.8	(47)
Other comprehensive income before reclassifications	71.6	29
Amounts reclassified from AOCL	0	0
Current period other comprehensive income	71.6	29
Ending Balance	92.4	(18)
Net Unrealized Gains (Losses) on Debt Securities Transferred to Held-to-Maturity
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(11.8)	(15.3)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from AOCL	1	0.6
Current period other comprehensive income	1	0.6
Ending Balance	(10.8)	(14.7)
Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	0.3	(2)
Other comprehensive income before reclassifications	0	0.5
Amounts reclassified from AOCL	0	0.3
Current period other comprehensive income	0	0.8
Ending Balance	0.3	(1.2)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(166.9)	(256.8)
Current period other comprehensive income	74.2	32.2
Ending Balance	$ (92.7)	$ (224.6)

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Amounts Reclassified from AOCL (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other non-interest expense	$ 27.5	$ 34.4
Interest expense - notes and debentures (interest rate locks are less than $0.1 million)	8.8	8.8
Income before income tax expense	(166.2)	(144.6)
Income tax expense	35.8	30
Net Income (Loss) Attributable to Parent	(130.4)	(114.6)
Reclassification out of AOCL
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net Income (Loss) Attributable to Parent	(2.6)	(2.7)
Reclassification out of AOCL | Net Actuarial Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other non-interest expense	(2)	(1.3)
Reclassification out of AOCL | Pension and Other Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before income tax expense	(2)	(1.3)
Income tax expense	0.4	(0.5)
Net Income (Loss) Attributable to Parent	(1.6)	(1.8)
Reclassification out of AOCL | Net Unrealized Gains (Losses) on Debt Securities Available-for-Sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before income tax expense	0	0
Income tax expense	0	0
Net Income (Loss) Attributable to Parent	0	0
Reclassification out of AOCL | Net Unrealized Gains (Losses) on Debt Securities Transferred to Held-to-Maturity
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before income tax expense	(1.3)	(0.8)
Income tax expense	0.3	0.2
Net Income (Loss) Attributable to Parent	(1)	(0.6)
Reclassification out of AOCL | Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before income tax expense	0	(0.4)
Income tax expense	0	0.1
Net Income (Loss) Attributable to Parent	0	(0.3)
Reclassification out of AOCL | Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges | Interest rate swaps
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest expense - notes and debentures (interest rate locks are less than $0.1 million)	0	(0.4)
Reclassification out of AOCL | Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges | Interest rate locks
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest expense - notes and debentures (interest rate locks are less than $0.1 million)	0	0
Maximum | Reclassification out of AOCL | Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges | Interest rate swaps
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net Income (Loss) Attributable to Parent	(0.1)	(0.1)
Maximum | Reclassification out of AOCL | Net Unrealized Gains (Losses) on Derivatives Accounted for as Cash Flow Hedges | Interest rate locks
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net Income (Loss) Attributable to Parent	$ (0.1)	$ (0.1)

Earnings Per Common Share (Deta

Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net income available to common shareholders	$ 126.9	$ 111.1
Dividends paid on and undistributed earnings allocated to participating securities	0	0
Earnings attributable to common shareholders	$ 126.9	$ 111.1
Weighted average common shares outstanding for basic EPS (in shares)	427.2	370.7
Effect of dilutive equity-based awards (in shares)	2.6	3.4
Weighted average common shares and common-equivalent shares for diluted EPS (in shares)	429.8	374.1
EPS:
Basic (USD per share)	$ 0.30	$ 0.30
Diluted (USD per share)	$ 0.30	$ 0.30
Anti-dilutive equity-based awards excluded from calculation of diluted EPS (in shares)	12.9	7.2

Goodwill and Other Acquisitio_2

Goodwill and Other Acquisition-Related Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Goodwill And Other Intangible Assets [Line Items]
Goodwill	$ 3,065,500,000		$ 3,065,500,000
Tax deductible goodwill amount	131,800,000		134,400,000
Other acquisition-related intangible assets	198,500,000		209,100,000
Amortization of other acquisition-related intangible assets	10,700,000	$ 6,700,000
Amortization expense attributable to other acquisition-related intangible assets, 2020	40,900,000
Amortization expense attributable to other acquisition-related intangible assets, 2021	36,100,000
Amortization expense attributable to other acquisition-related intangible assets, 2022	31,700,000
Amortization expense attributable to other acquisition-related intangible assets, 2023	24,000,000
Amortization expense attributable to other acquisition-related intangible assets, 2024	20,300,000
Amortization expense attributable to other acquisition-related intangible assets, 2025	17,300,000
Impairment losses relating to goodwill or other acquisition-related intangible assets	0	$ 0
Commercial Banking
Goodwill And Other Intangible Assets [Line Items]
Goodwill	1,970,000,000		1,970,000,000
Retail Banking
Goodwill And Other Intangible Assets [Line Items]
Goodwill	1,010,000,000		1,010,000,000
Wealth Management
Goodwill And Other Intangible Assets [Line Items]
Goodwill	88,500,000		$ 88,500,000
Core Deposit Intangibles
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	118,900,000
Trade Name
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	49,000,000
Client Relationship
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	17,400,000
Trust relationships
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	7,000,000
Insurance Relationships
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	3,700,000
Favorable Lease Agreement
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	2,300,000
Noncompete Agreements
Goodwill And Other Intangible Assets [Line Items]
Other acquisition-related intangible assets	$ 200,000

Employee Benefit Plans - Employ

Employee Benefit Plans - Employee Pension and Other Postretirement Plans (Detail)	3 Months Ended
	Mar. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Average compensation term on which pension plan benefits are based, in years	5 years
Average compensation term within last ten years on which pension plan benefits are based, in years	5 years
Term considered when determining employee pension benefits, in years	10 years
Minimum age requirement to participate in pension plan, years	18 years
Minimum service hours per year requirement to participate in pension plan	1000 hours
People's Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of covered employee's eligible compensation	3.00%

Employee Benefit Plans - Compon

Employee Benefit Plans - Components of Net Periodic Benefit (Income) Expense and Other Amounts (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 4.9	$ 5.6
Expected return on plan assets	(12.4)	(11.4)
Recognized net actuarial loss	2	1.3
Settlements	0.8	0.6
Net periodic benefit (income) expense	(4.7)	(3.9)
Net actuarial loss	(2)	(1.3)
Prior service credit	0	0
Total pre-tax changes recognized in other comprehensive income (loss)	(2)	(1.3)
Total recognized in net periodic benefit (income) expense and other comprehensive income (loss)	(6.7)	(5.2)
Other Postretirement Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	0.3	0.3
Expected return on plan assets	0	0
Recognized net actuarial loss	0	0
Settlements	0	0
Net periodic benefit (income) expense	0.3	0.3
Net actuarial loss	0	0
Prior service credit	0	0
Total pre-tax changes recognized in other comprehensive income (loss)	0	0
Total recognized in net periodic benefit (income) expense and other comprehensive income (loss)	$ 0.3	$ 0.3

Employee Benefit Plans - Empl_2

Employee Benefit Plans - Employee Stock Ownership Plan (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2007	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Retirement Benefits [Abstract]
ESOP loan	$ 216.8	$ 171.8
ESOP, shares to be purchased	10,453,575
Loan repayments expected annual through 2036	$ 18.8
Cash dividends paid on unallocated ESOP shares		$ 1.1
Minimum age requirement to participate in ESOP		18 years
Minimum work experience within 12 months of hire needed to participate in ESOP		1000 hours
ESOP common stock allocated (in shares)		4,616,996
Unallocated common stock of Employee Stock Ownership Plan (in shares)		5,836,579		5,900,000
Fair value of deferred ESOP shares		$ 64.5
ESOP compensation expense		$ 1.2	$ 1.4

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans			$ 61.9
Provision for credit losses	$ 33.5	$ 5.6
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans			61.9
Nonrecurring | Collateral Pledged
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	$ 15.2
GSE mortgage-backed securities | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maturity period of available-for-sale residential mortgage-backed securities portfolio	10 years
GSE mortgage-backed securities | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maturity period of available-for-sale residential mortgage-backed securities portfolio	40 years
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount to impaired loans	10.00%
Level 3 | Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans			$ 61.9
Level 3 | Nonrecurring | Collateral Pledged
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Provision for credit losses	$ 3.9
Related Allowance for Loan Losses	$ 8.9

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities on Recurring Basis (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading debt securities	$ 0	$ 7.1
Debt securities available-for-sale, at fair value	4,276.6	3,564.3
Equity securities	6.2	8.2
Other assets	2,396	1,853
Derivative assets	36.1	18.4
Fair value of total assets measured at fair value on a recurring basis	5,271.2	3,971.6
Financial liabilities	197.3	81.6
Fair value of total liabilities measured at fair value on a recurring basis	198.5	96.2
Exchange-traded funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	39.8	47.7
Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	2.9	3.3
Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets		0
U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading debt securities		7.1
U.S. Treasury and agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	747.2	687.1
GSE mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	3,529.4	2,877.2
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	6.2	8.2
Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	932.9	337.6
Financial liabilities	184.5	92.1
Interest rate caps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	3.6	1.7
Financial liabilities	3.6	1.7
Risk Participation Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0.5	0.1
Foreign exchange contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	8.6	1.2
Financial liabilities	9.2	1.8
Forward commitments to sell residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0.6	0.5
Interest rate-lock commitments on residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0.7	0.5
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total assets measured at fair value on a recurring basis	796.1	753.4
Fair value of total liabilities measured at fair value on a recurring basis	0	0
Level 1 | Exchange-traded funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	39.8	47.7
Level 1 | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	2.9	3.3
Level 1 | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets		0
Level 1 | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading debt securities		7.1
Level 1 | U.S. Treasury and agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	747.2	687.1
Level 1 | GSE mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	0	0
Level 1 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	6.2	8.2
Level 1 | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Financial liabilities	0	0
Level 1 | Interest rate caps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Financial liabilities	0	0
Level 1 | Risk Participation Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0	0
Level 1 | Foreign exchange contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Financial liabilities	0	0
Level 1 | Forward commitments to sell residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Level 1 | Interest rate-lock commitments on residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total assets measured at fair value on a recurring basis	4,475.1	3,218.2
Fair value of total liabilities measured at fair value on a recurring basis	198.5	96.2
Level 2 | Exchange-traded funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0	0
Level 2 | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0	0
Level 2 | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets		0
Level 2 | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading debt securities		0
Level 2 | U.S. Treasury and agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	0	0
Level 2 | GSE mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	3,529.4	2,877.2
Level 2 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Level 2 | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	932.9	337.6
Financial liabilities	184.5	92.1
Level 2 | Interest rate caps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	3.6	1.7
Financial liabilities	3.6	1.7
Level 2 | Risk Participation Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0.5	0.1
Level 2 | Foreign exchange contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	8.6	1.2
Financial liabilities	9.2	1.8
Level 2 | Forward commitments to sell residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0.6	0.5
Level 2 | Interest rate-lock commitments on residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0.7	0.5
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total assets measured at fair value on a recurring basis	0	0
Fair value of total liabilities measured at fair value on a recurring basis	0	0
Level 3 | Exchange-traded funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0	0
Level 3 | Mutual funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets	0	0
Level 3 | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets		0
Level 3 | U.S. Treasury
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading debt securities		0
Level 3 | U.S. Treasury and agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	0	0
Level 3 | GSE mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available-for-sale, at fair value	0	0
Level 3 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0	0
Level 3 | Interest rate swaps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Financial liabilities	0	0
Level 3 | Interest rate caps
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Financial liabilities	0	0
Level 3 | Risk Participation Agreements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	0	0
Level 3 | Foreign exchange contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Financial liabilities	0	0
Level 3 | Forward commitments to sell residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Level 3 | Interest rate-lock commitments on residential mortgage loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	$ 0	$ 0

Fair Value Measurements - Ass_2

Fair Value Measurements - Assets on Non-Recurring Basis (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	$ 19,200,000		$ 511,300,000
Impaired loans			61,900,000
Fair value of total assets measured at fair value on a recurring basis	5,271,200,000		3,971,600,000
Repossessed assets	4,600,000		4,200,000
Provision for credit losses	33,500,000	$ 5,600,000
Impaired Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Provision for credit losses		600,000
REO and Repossessed Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Provision for credit losses	1,200,000	300,000
Nonoperating Income (Expense)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Write downs and net loss on sale of foreclosed/repossessed assets charged to non-interest expense total	400,000	100,000
Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate owned	7,300,000		7,300,000
Residential mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value adjustments	0	$ 0
Real estate owned	9,500,000		11,900,000
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total assets measured at fair value on a recurring basis	796,100,000		753,400,000
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total assets measured at fair value on a recurring basis	4,475,100,000		3,218,200,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total assets measured at fair value on a recurring basis	0		0
Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	19,200,000
Impaired loans			61,900,000
REO and repossessed assets	21,400,000		23,400,000
Servicing Asset	7,700,000		10,300,000
Fair value of total assets measured at fair value on a recurring basis	48,300,000		606,900,000
Fair value adjustments	3,000,000
Nonrecurring | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			157,900,000
Nonrecurring | Other consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			333,700,000
Nonrecurring | Residential mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	19,200,000		19,700,000
Nonrecurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	0
Impaired loans			0
REO and repossessed assets	0		0
Servicing Asset	0		0
Fair value of total assets measured at fair value on a recurring basis	0		0
Nonrecurring | Level 1 | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			0
Nonrecurring | Level 1 | Other consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			0
Nonrecurring | Level 1 | Residential mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			0
Nonrecurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	19,200,000
Impaired loans			0
REO and repossessed assets	0		0
Servicing Asset	0		0
Fair value of total assets measured at fair value on a recurring basis	19,200,000		19,700,000
Nonrecurring | Level 2 | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			0
Nonrecurring | Level 2 | Other consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			0
Nonrecurring | Level 2 | Residential mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			19,700,000
Nonrecurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale	0
Impaired loans			61,900,000
REO and repossessed assets	21,400,000		23,400,000
Servicing Asset	7,700,000		10,300,000
Fair value of total assets measured at fair value on a recurring basis	$ 29,100,000		587,200,000
Nonrecurring | Level 3 | Commercial real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			157,900,000
Nonrecurring | Level 3 | Other consumer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			333,700,000
Nonrecurring | Level 3 | Residential mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held-for-sale			$ 0

Fair Value Measurements - Finan

Fair Value Measurements - Financial Instruments (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	$ 507.6	$ 484.2
Short-term investments	744.3	316.8
Debt securities held-to-maturity	3,863.4	3,869.2
FHLB and FRB stock	407.2	341.1
Time deposits	8,840.2	9,205.5
FHLB advances	4,489.7	3,125.4
Federal funds purchased	1,120	1,620
Customer repurchase agreements	301.1	409.1
Notes and debentures	1,012.6	993.1
Impaired loans		61.9
Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans		61.9
Collateral Pledged | Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans	15.2
Level 1 | Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans		0
Level 2 | Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans		0
Level 3 | Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans		61.9
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	507.6	484.2
Short-term investments	744.3	316.8
Debt securities held-to-maturity	3,861.5	3,869.2
FHLB and FRB stock	407.2	341.1
Total loans, net	43,927.1	43,287.6
Time deposits	8,840.2	9,205.5
Other deposits	35,900.9	34,384
FHLB advances	4,489.7	3,125.4
Federal funds purchased	1,120	1,620
Customer repurchase agreements	301.1	409.1
Other borrowings
Notes and debentures	1,012.6	993.1
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	507.6	484.2
Short-term investments	744.3	316.8
Debt securities held-to-maturity	4,065.2	4,020
FHLB and FRB stock	407.2	341.1
Total loans, net	44,597.2	43,355
Time deposits	8,891.5	9,218.1
Other deposits	35,900.9	34,384
FHLB advances	4,490.7	3,125.5
Federal funds purchased	1,120	1,620
Customer repurchase agreements	301.1	409.1
Other borrowings		11
Notes and debentures	995.8	1,021.3
Fair Value | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	507.6	484.2
Short-term investments	0	0
Debt securities held-to-maturity	0	0
FHLB and FRB stock	0	0
Total loans, net	0	0
Time deposits	0	0
Other deposits	0	0
FHLB advances	0	0
Federal funds purchased	0	0
Customer repurchase agreements	0	0
Other borrowings		0
Notes and debentures	0	0
Fair Value | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0	0
Short-term investments	744.3	316.8
Debt securities held-to-maturity	4,063.7	4,018.5
FHLB and FRB stock	407.2	341.1
Total loans, net	9,999.3	10,072.1
Time deposits	8,891.5	9,218.1
Other deposits	35,900.9	34,384
FHLB advances	4,490.7	3,125.5
Federal funds purchased	1,120	1,620
Customer repurchase agreements	301.1	409.1
Other borrowings		11
Notes and debentures	995.8	1,021.3
Fair Value | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0	0
Short-term investments	0	0
Debt securities held-to-maturity	1.5	1.5
FHLB and FRB stock	0	0
Total loans, net	34,597.9	33,282.9
Time deposits	0	0
Other deposits	0	0
FHLB advances	0	0
Federal funds purchased	0	0
Customer repurchase agreements	0	0
Other borrowings		0
Notes and debentures	$ 0	$ 0

Derivative Financial Instrume_3

Derivative Financial Instruments and Hedging Activities - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Treasury Forward Interest Rate Locks (T-Locks)
Derivative [Line Items]
Period hedged items affected earnings, years	10 years
Derivative instruments hedge description	to hedge the risk that the 10-year U.S. Treasury yield would rise
Unrealized gain (loss) on derivatives	$ 900,000
Treasury Forward Interest Rate Locks (T-Locks) | Subordinated notes
Derivative [Line Items]
Senior notes issuance	500,000,000
Derivatives Designated as Hedging Instruments | Interest rate swaps | Cash flow | Loans
Derivative [Line Items]
Notional amounts of derivatives	$ 210,000,000	$ 210,000,000
LIBOR basis points	one-month LIBOR
Derivatives Designated as Hedging Instruments | Interest rate swaps | Subordinated notes | Fair value
Derivative [Line Items]
Notional amounts of derivatives	$ 375,000,000
LIBOR basis points	three-month LIBOR
Subordinated notes	$ 400,000,000
Basis points	1.265%
Derivatives Designated as Hedging Instruments | Interest rate swaps | FHLB advances | Cash flow
Derivative [Line Items]
Notional amounts of derivatives	$ 550,000,000	$ 0

Derivative Financial Instrume_4

Derivative Financial Instruments and Hedging Activities - Schedule of Notional Amount and Fair Value (Detail) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount Recognized	$ 36,100,000	$ 18,400,000
Gross Amounts Recognized	945,700,000	341,000,000
Financial liabilities	197,300,000	81,600,000
Financial liabilities	198,500,000	96,200,000
Forward commitments to sell residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount Recognized	600,000	500,000
Interest rate-lock commitments on residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Financial liabilities	700,000	500,000
Derivatives Not Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amounts Recognized	945,700,000	341,000,000
Financial liabilities	198,500,000	96,200,000
Derivatives Not Designated as Hedging Instruments | Forward commitments to sell residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	77,700,000	23,300,000
Gross Amounts Recognized	600,000	500,000
Financial liabilities	0	0
Derivatives Not Designated as Hedging Instruments | Interest rate-lock commitments on residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	53,800,000	33,600,000
Gross Amounts Recognized	0	0
Financial liabilities	700,000	500,000
Derivatives Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amounts Recognized	0	0
Financial liabilities	0	0
Interest rate swaps | Derivatives Not Designated as Hedging Instruments | Commercial customers
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	9,207,600,000	8,847,700,000
Gross Amounts Recognized	905,400,000	320,500,000
Financial liabilities	0	13,900,000
Interest rate swaps | Derivatives Not Designated as Hedging Instruments | Institutional counterparties
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	9,211,400,000	8,851,800,000
Gross Amount Recognized	27,500,000	17,100,000
Financial liabilities	184,500,000	78,200,000
Interest rate swaps | Derivatives Designated as Hedging Instruments | Cash flow | FHLB advances
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	550,000,000	0
Gross Amounts Recognized	0	0
Financial liabilities	0	0
Interest rate swaps | Derivatives Designated as Hedging Instruments | Cash flow | Loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	210,000,000	210,000,000
Gross Amounts Recognized	0	0
Financial liabilities	0	0
Interest rate swaps | Derivatives Designated as Hedging Instruments | Subordinated notes | Fair value
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	375,000,000	375,000,000
Gross Amounts Recognized	0	0
Financial liabilities	0	0
Interest rate caps | Derivatives Not Designated as Hedging Instruments | Commercial customers
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	253,400,000	246,000,000
Gross Amounts Recognized	3,600,000	1,600,000
Financial liabilities	0	100,000
Interest rate caps | Derivatives Not Designated as Hedging Instruments | Institutional counterparties
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	253,400,000	246,000,000
Gross Amount Recognized	0	100,000
Financial liabilities	3,600,000	1,600,000
Risk Participation Agreements | Derivatives Not Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	910,300,000	882,800,000
Gross Amounts Recognized	0	0
Financial liabilities	500,000	100,000
Foreign exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gross Amount Recognized	8,600,000	1,200,000
Financial liabilities	9,200,000	1,800,000
Foreign exchange contracts | Derivatives Not Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amounts	237,700,000	180,400,000
Gross Amount Recognized	8,600,000	1,200,000
Financial liabilities	$ 9,200,000	$ 1,800,000

Derivative Financial Instrume_5

Derivative Financial Instruments and Hedging Activities - Impact on Income and AOCI (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	$ 9.8	$ 2.3
Amount of Pre-Tax Gain (Loss) Recognized in AOCL	0.1	0.6
Derivatives Not Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	9.4	3
Derivatives Not Designated as Hedging Instruments | Forward commitments to sell residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0.2	0
Derivatives Not Designated as Hedging Instruments | Interest rate-lock commitments on residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	(0.2)	0
Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Commercial customers
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	613.6	111.6
Derivatives Not Designated as Hedging Instruments | Interest rate swaps | Institutional counterparties
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	(603.7)	(108.8)
Derivatives Not Designated as Hedging Instruments | Interest rate caps | Commercial customers
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	2	1.1
Derivatives Not Designated as Hedging Instruments | Interest rate caps | Institutional counterparties
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	(2)	(1.2)
Derivatives Not Designated as Hedging Instruments | Foreign exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0.1	0.2
Derivatives Not Designated as Hedging Instruments | Risk Participation Agreements
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	(0.6)	0.1
Derivatives Designated as Hedging Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0.4	(0.7)
Amount of Pre-Tax Gain (Loss) Recognized in AOCL	0.1	0.6
Derivatives Designated as Hedging Instruments | Cash flow | Interest rate-lock commitments on residential mortgage loans
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0	0
Amount of Pre-Tax Gain (Loss) Recognized in AOCL	0	0
Derivatives Designated as Hedging Instruments | Cash flow | Interest rate-lock commitments on residential mortgage loans | Maximum
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0.1	0.1
Amount of Pre-Tax Gain (Loss) Recognized in AOCL	0.1	0.1
Derivatives Designated as Hedging Instruments | Interest rate swaps | Fair value
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0.4	(0.3)
Derivatives Designated as Hedging Instruments | Interest rate swaps | Cash flow
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pre-Tax Gain (Loss) Recognized in Earnings	0	(0.4)
Amount of Pre-Tax Gain (Loss) Recognized in AOCL	$ 0.1	$ 0.6

Balance Sheet Offsetting - Summ

Balance Sheet Offsetting - Summary of Gross Presentation, Instruments Offset (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financial assets:
Gross Amount Recognized	$ 36.1	$ 18.4
Gross Amount Offset	0	0
Net Amount Presented	36.1	18.4
Gross Amounts Not Offset, Financial Instruments	0	(1.9)
Gross Amounts Not Offset, Collateral	0	0
Net Amount	36.1	16.5
Financial liabilities:
Gross Amount Recognized	197.3	81.6
Gross Amount Offset	0	0
Net Amount Presented	197.3	81.6
Gross Amounts Not Offset, Financial Instruments	0	(1.9)
Gross Amounts Not Offset, Collateral	(188.1)	(77.9)
Net Amount	9.2	1.8
Foreign exchange contracts
Financial assets:
Gross Amount Recognized	8.6	1.2
Gross Amount Offset	0	0
Net Amount Presented	8.6	1.2
Gross Amounts Not Offset, Financial Instruments	0	0
Gross Amounts Not Offset, Collateral	0	0
Net Amount	8.6	1.2
Financial liabilities:
Gross Amount Recognized	9.2	1.8
Gross Amount Offset	0	0
Net Amount Presented	9.2	1.8
Gross Amounts Not Offset, Financial Instruments	0	0
Gross Amounts Not Offset, Collateral		0
Net Amount	9.2	1.8
Counterparty A | Interest Rate Swaps/Caps
Financial assets:
Gross Amount Recognized	0	0.2
Gross Amount Offset	0	0
Net Amount Presented	0	0.2
Gross Amounts Not Offset, Financial Instruments	0	(0.2)
Gross Amounts Not Offset, Collateral	0	0
Net Amount	0	0
Financial liabilities:
Gross Amount Recognized	6.4	2.3
Gross Amount Offset	0	0
Net Amount Presented	6.4	2.3
Gross Amounts Not Offset, Financial Instruments	0	(0.2)
Gross Amounts Not Offset, Collateral	(6.4)	(2.1)
Net Amount	0	0
Counterparty B | Interest Rate Swaps/Caps
Financial assets:
Gross Amount Recognized	0	0.1
Gross Amount Offset	0	0
Net Amount Presented	0	0.1
Gross Amounts Not Offset, Financial Instruments	0	(0.1)
Gross Amounts Not Offset, Collateral	0	0
Net Amount	0	0
Financial liabilities:
Gross Amount Recognized	9.9	5.5
Gross Amount Offset	0	0
Net Amount Presented	9.9	5.5
Gross Amounts Not Offset, Financial Instruments	0	(0.1)
Gross Amounts Not Offset, Collateral	(9.9)	(5.4)
Net Amount	0	0
Counterparty C | Interest Rate Swaps/Caps
Financial assets:
Gross Amount Recognized	0	0.4
Gross Amount Offset	0	0
Net Amount Presented	0	0.4
Gross Amounts Not Offset, Financial Instruments	0	(0.4)
Gross Amounts Not Offset, Collateral	0	0
Net Amount	0	0
Financial liabilities:
Gross Amount Recognized	64.2	28.2
Gross Amount Offset	0	0
Net Amount Presented	64.2	28.2
Gross Amounts Not Offset, Financial Instruments	0	(0.4)
Gross Amounts Not Offset, Collateral	(64.2)	(27.8)
Net Amount	0	0
Counterparty D | Interest Rate Swaps/Caps
Financial assets:
Gross Amount Recognized	0	0.1
Gross Amount Offset	0	0
Net Amount Presented	0	0.1
Gross Amounts Not Offset, Financial Instruments	0	(0.1)
Gross Amounts Not Offset, Collateral	0	0
Net Amount	0	0
Financial liabilities:
Gross Amount Recognized	24.6	10.9
Gross Amount Offset	0	0
Net Amount Presented	24.6	10.9
Gross Amounts Not Offset, Financial Instruments	0	(0.1)
Gross Amounts Not Offset, Collateral	(24.6)	(10.8)
Net Amount	0	0
Counterparty E | Interest Rate Swaps/Caps
Financial assets:
Gross Amount Recognized	27.5	15.3
Gross Amount Offset	0	0
Net Amount Presented	27.5	15.3
Gross Amounts Not Offset, Financial Instruments	0	0
Gross Amounts Not Offset, Collateral	0	0
Net Amount	27.5	15.3
Financial liabilities:
Gross Amount Recognized	0	0
Gross Amount Offset	0	0
Net Amount Presented	0	0
Gross Amounts Not Offset, Financial Instruments	0	0
Gross Amounts Not Offset, Collateral		0
Net Amount	0	0
Other Counterparties | Interest Rate Swaps/Caps
Financial assets:
Gross Amount Recognized	0	1.1
Gross Amount Offset	0	0
Net Amount Presented	0	1.1
Gross Amounts Not Offset, Financial Instruments	0	(1.1)
Gross Amounts Not Offset, Collateral	0	0
Net Amount	0	0
Financial liabilities:
Gross Amount Recognized	83	32.9
Gross Amount Offset	0	0
Net Amount Presented	83	32.9
Gross Amounts Not Offset, Financial Instruments	0	(1.1)
Gross Amounts Not Offset, Collateral	(83)	(31.8)
Net Amount	$ 0	$ 0

Balance Sheet Offsetting - Addi

Balance Sheet Offsetting - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
U.S. Treasury
Offsettting Assets and Liabilities [Line Items]
Fair value of treasury securities	$ 454.2	$ 462.4
Mortgage-Backed Securities
Offsettting Assets and Liabilities [Line Items]
Fair value of treasury securities	$ 464	$ 457.5

Balance Sheet Offsetting - Su_2

Balance Sheet Offsetting - Summary of Collateral Swaps (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Total repurchase agreements
Net Amount Presented	$ 301.1	$ 409.1
Collateral Swaps
Total resale agreements
Gross Amount Recognized	450	450
Gross Amount Offset	(450)	(450)
Net Amount Presented	0	0
Total repurchase agreements
Gross Amount Recognized	450	450
Gross Amount Offset	(450)	(450)
Net Amount Presented	$ 0	$ 0

New Accounting Standards (Detai

New Accounting Standards (Details) - USD ($) $ in Millions	Jan. 01, 2020	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]
Allowance for loan losses		$ 341.7	$ 246.6	$ 240.9	$ 240.4
Off-Balance Sheet, Credit Loss, Liability		20.7	5.6
Debt securities, allowance for credit loss		1.9
Retained earnings		$ 1,514.5	1,512.8
Cumulative Effect, Period Of Adoption, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Allowance for loan losses			72.2
Off-Balance Sheet, Credit Loss, Liability			$ 14.5
Accounting Standards Update 2016-13
Summary Of Significant Accounting Policies [Line Items]
Decrease in risk-based capital ratios		0.10%
Accounting Standards Update 2016-13 | Cumulative Effect, Period Of Adoption, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Allowance for loan losses	$ 72
Adjustment to amortized cost basis	28
Off-Balance Sheet, Credit Loss, Liability	15
Debt securities, allowance for credit loss	2
Accounting Standards Update 2016-13 | Retained Earnings | Cumulative Effect, Period Of Adoption, Adjustment
Summary Of Significant Accounting Policies [Line Items]
Retained earnings	$ (46)

Uncategorized Items - pbct-2020

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (45,900,000)
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ (45,900,000)