| Cover | 12 Months Ended |
| Dec. 31, 2022 | |
| Document Information [Line Items] | |
| Document Type | PRE 14A |
| Amendment Flag | false |
| Entity Information [Line Items] | |
| Entity Registrant Name | Webster Financial Corporation |
| Entity Central Index Key | 0000801337 |
| Pay vs Performance Disclosure | 12 Months Ended | ||
| Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | |
| Pay vs Performance Disclosure [Table] | |||
| Pay vs Performance [Table Text Block] | PAY VERSUS PERFORMANCE As required by Section 953(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act, and Item 402(v) of Regulation S-K, 2022 Pay versus Performance 1 Value of Initial Fixed Year Summary Compensation 2 Average non-CEO Average non-CEO 3 Webster Peer 4 Net Income Adjusted 5 2022 8,076,856 6,999,441 5,303,542 4,464,849 99.37 116.10 644.3 1,336.7 2021 4,721,527 5,764,745 1,591,343 1,951,435 113.57 124.74 408.9 526.5 2020 3,487,859 2,659,016 1,290,681 921,679 83.13 91.29 220.6 470.0 1 The NEOs included in each year are as follows: for 2022, Chief Executive Officer is Mr. Ciulla and the other NEOs are Messrs. Kopnisky, MacInnes, Massiani, and Motl; for 2021, Chief Executive Officer is Mr. Ciulla and the other NEOs are Messrs. MacInnes, Motl, Wilkins, and Bley; for 2020, CEO is Mr. Ciulla and the other NEOs are Messrs. MacInnes, Motl, Wilkins, Bley, and Mhatre. 2 The amounts in this column include deductions and additions from the Summary Compensation Table Total for the CEO as follows: for 2022, deduction of equity granted during the year of $4,824,116, deduction of dividends paid of $285,878, addition of the value of equity granted during 2022 that remains unvested based on year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end). 3 The amounts in this column include deductions and additions from the Summary Compensation Table Total for the average of the other NEOs as follows: for 2022, deduction of equity granted during the year of $3,119,233, deduction of dividends paid of $72,947, addition of the value of equity granted during 2022 that remains unvested based on year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end). 4 The amounts in this column are calculated using the KBW Regional Banking index as the Peer Group TSR. 5 Adjusted PPNR is derived from its GAAP number by adjusting for one-time non-recurring | ||
| Company Selected Measure Name | Adjusted PPNR | ||
| Named Executive Officers, Footnote [Text Block] | 1 The NEOs included in each year are as follows: for 2022, Chief Executive Officer is Mr. Ciulla and the other NEOs are Messrs. Kopnisky, MacInnes, Massiani, and Motl; for 2021, Chief Executive Officer is Mr. Ciulla and the other NEOs are Messrs. MacInnes, Motl, Wilkins, and Bley; for 2020, CEO is Mr. Ciulla and the other NEOs are Messrs. MacInnes, Motl, Wilkins, Bley, and Mhatre. | ||
| Peer Group Issuers, Footnote [Text Block] | The amounts in this column are calculated using the KBW Regional Banking index as the Peer Group TSR. | ||
| PEO Total Compensation Amount | $ 8,076,856 | $ 4,721,527 | $ 3,487,859 |
| PEO Actually Paid Compensation Amount | $ 6,999,441 | 5,764,745 | 2,659,016 |
| Adjustment To PEO Compensation, Footnote [Text Block] | The amounts in this column include deductions and additions from the Summary Compensation Table Total for the CEO as follows: for 2022, deduction of equity granted during the year of $4,824,116, deduction of dividends paid of $285,878, addition of the value of equity granted during 2022 that remains unvested based on year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end). | ||
| Non-PEO NEO Average Total Compensation Amount | $ 5,303,542 | 1,591,343 | 1,290,681 |
| Non-PEO NEO Average Compensation Actually Paid Amount | $ 4,464,849 | 1,951,435 | 921,679 |
| Adjustment to Non-PEO NEO Compensation Footnote [Text Block] | The amounts in this column include deductions and additions from the Summary Compensation Table Total for the average of the other NEOs as follows: for 2022, deduction of equity granted during the year of $3,119,233, deduction of dividends paid of $72,947, addition of the value of equity granted during 2022 that remains unvested based on year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end year-end). | ||
| Compensation Actually Paid vs. Total Shareholder Return [Text Block] | The Company’s actual pay for its CEO and other NEOs as compared to Net Income and adjusted PPNR and actu al | ||
| Compensation Actually Paid vs. Net Income [Text Block] | The Company’s actual pay for its CEO and other NEOs as compared to Net Income and adjusted PPNR and actu al | ||
| Compensation Actually Paid vs. Company Selected Measure [Text Block] | The Company’s actual pay for its CEO and other NEOs as compared to Net Income and adjusted PPNR and actu al | ||
| Tabular List [Table Text Block] | Below is an unranked list of the most important performance measures used to link executive compensation actually paid to the Company’s performance: Key Performance Measures 1 Pre-Provision Net Revenue 2 Return on Average Assets 3 Relative Total Stockholder Return 4 Return on Equity 5 Strategic Goals 6 Risk Management 7 Leadership | ||
| Total Shareholder Return Amount | $ 99.37 | 113.57 | 83.13 |
| Peer Group Total Shareholder Return Amount | 116.1 | 124.74 | 91.29 |
| Net Income (Loss) | $ 644,300 | $ 408,900 | $ 220,600 |
| Company Selected Measure Amount | 1,336,700 | 526,500 | 470,000 |
| PEO Name | Mr. Ciulla | Mr. Ciulla | Mr. Ciulla |
| Measure [Axis]: 1 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Pre-Provision Net Revenue | ||
| Non-GAAP Measure Description [Text Block] | Adjusted PPNR is derived from its GAAP number by adjusting for one-time non-recurring | ||
| Measure [Axis]: 2 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Return on Average Assets | ||
| Measure [Axis]: 3 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Relative Total Stockholder Return | ||
| Measure [Axis]: 4 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Return on Equity | ||
| Measure [Axis]: 5 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Strategic Goals | ||
| Measure [Axis]: 6 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Risk Management | ||
| Measure [Axis]: 7 | |||
| Pay vs Performance Disclosure [Table] | |||
| Measure Name | Leadership | ||
| PEO [Member] | Deduction of Equity Granted [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ (4,824,116) | $ (1,985,580) | $ (1,509,732) |
| PEO [Member] | Deduction of Dividends Paid [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (285,878) | (102,043) | (62,357) |
| PEO [Member] | Addition of the Value of Equity Granted [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 4,194,346 | 2,246,341 | 1,563,568 |
| PEO [Member] | Change in Fair Value of Unvested Equity Awards. [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (267,513) | 562,148 | (490,383) |
| PEO [Member] | Change in Fair Value of Equity Awards that Vested [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 105,746 | 322,352 | (308,139) |
| PEO [Member] | Deduction of the Aggregate Change in Pension Value [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (21,800) | ||
| Non-PEO NEO [Member] | Deduction of Equity Granted [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (3,119,233) | (521,280) | (426,387) |
| Non-PEO NEO [Member] | Deduction of Dividends Paid [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (72,947) | (37.069) | (36,062) |
| Non-PEO NEO [Member] | Addition of the Value of Equity Granted [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | 2,670,811 | 589,735 | 368,283 |
| Non-PEO NEO [Member] | Change in Fair Value of Unvested Equity Awards. [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | (201,847) | 186,516 | (206,389) |
| Non-PEO NEO [Member] | Change in Fair Value of Equity Awards that Vested [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ (115,477) | $ 142,190 | (65,468) |
| Non-PEO NEO [Member] | Deduction of the Aggregate Change in Pension Value [Member] | |||
| Pay vs Performance Disclosure [Table] | |||
| Adjustment to Compensation Amount | $ (14,900) | ||
