Webster Financial (WBS) 10-Q/A 6 Nov 14 2014 Q3 Quarterly report (amended) Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Oct. 31, 2014
Document Documentand Entity Information [Abstract]	'	'
Amendment Description	'Explanatory Note The Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2014 filed by Webster Financial Corporation (the “Company”) with the Securities and Exchange Commission on November 5, 2014 inadvertently omitted the following exhibits: EXHIBIT 31.1 Certification of the Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. EXHIBIT 31.2 Certification of the Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. EXHIBIT 32.1 Certification of the Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. EXHIBIT 32.2 Certification of the Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. The exhibits are included with this Amendment No. 1 to Quarterly Report on Form 10-Q/A. No revisions are being made to the Company's Form 10-Q except for the filing of the exhibits listed above. This amendment does not reflect events occurring after the filing of the Form 10-Q, or modify or update those disclosures that may be affected by subsequent events, and no other changes are being made to any other disclosure contained in the Form 10-Q.	'
Document Type	'10-Q	'
Amendment Flag	'true	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'WBS	'
Entity Registrant Name	'WEBSTER FINANCIAL CORP	'
Entity Central Index Key	'0000801337	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	90,245,947

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Assets:	'		'
Cash and due from banks	$207,128		$223,616
Interest-bearing deposits	105,394		23,674
Securities available-for-sale, at fair value	2,873,886		3,106,931
Securities held-to-maturity (fair value of $3,699,825 and $3,370,912)	3,641,979		3,358,721
Federal Home Loan Bank and Federal Reserve Bank stock	171,174		158,878
Loans held for sale	26,083		20,802
Loans and leases	13,513,502	[1]	12,699,776	[1]
Allowance for loan and lease losses	-156,482		-152,573
Loans and leases, net	13,357,020		12,547,203
Deferred tax asset, net	62,884		65,109
Premises and equipment, net	118,608		121,605
Goodwill	529,887		529,887
Other intangible assets, net	3,082		5,351
Cash surrender value of life insurance policies	438,100		430,535
Accrued interest receivable and other assets	291,657		260,687
Total assets	21,826,882		20,852,999
Liabilities and shareholders' equity:	'		'
Non-interest-bearing	3,256,741		3,128,152
Interest-bearing	12,290,177		11,726,268
Total deposits	15,546,918		14,854,420
Securities sold under agreements to repurchase and other borrowings	1,236,975		1,331,662
Federal Home Loan Bank advances	2,290,204		2,052,421
Long-term debt	226,208		228,365
Accrued expenses and other liabilities	215,727		176,943
Total liabilities	19,516,032		18,643,811
Shareholders’ equity:	'		'
Common stock, $.01 par value: Authorized - 200,000,000 shares: Issued - 93,381,269 and 93,366,673 shares	934		934
Paid-in capital	1,128,453		1,125,584
Retained earnings	1,172,372		1,080,488
Treasury stock, at cost (3,292,072 and 3,407,256 shares)	-106,639		-100,918
Accumulated other comprehensive loss	-35,919		-48,549
Total shareholders' equity	2,310,850		2,209,188
Total liabilities and shareholders' equity	21,826,882		20,852,999
Series A Preferred Stock [Member]	'		'
Shareholders’ equity:	'		'
Preferred stock, $.01 par value; Authorized - 3,000,000 shares:	28,939		28,939
Series E Preferred Stock [Member]	'		'
Shareholders’ equity:	'		'
Preferred stock, $.01 par value; Authorized - 3,000,000 shares:	$122,710		$122,710
[1]	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Securities held-to-maturity ,fair value	$3,699,825	$3,370,912
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	3,000,000	3,000,000
Common stock par value	$0.01	$0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	93,381,269	90,366,673
Treasury stock ,shares	3,292,072	3,407,256
Series A Preferred Stock [Member]	'	'
Preferred stock, shares issued	28,939	28,939
Preferred stock, shares outstanding	28,939	28,939
Series E Preferred Stock [Member]	'	'
Preferred stock, shares issued	5,060	5,060
Preferred stock, shares outstanding	5,060	5,060

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Income (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Interest Income:	'	'	'	'
Interest and fees on loans and leases	$129,227	$123,257	$379,008	$365,262
Taxable interest and dividends on securities	46,349	42,722	142,442	128,320
Non-taxable interest on securities	4,099	5,201	13,109	16,586
Loans held for sale	239	573	631	1,761
Total interest income	179,914	171,753	535,190	511,929
Interest Expense:	'	'	'	'
Deposits	11,345	10,908	32,840	35,782
Securities sold under agreements to repurchase and other borrowings	4,587	5,283	14,874	15,522
Federal Home Loan Bank advances	4,203	3,753	12,052	12,299
Long-term debt	2,409	1,822	7,631	5,482
Total interest expense	22,544	21,766	67,397	69,085
Net interest income	157,370	149,987	467,793	442,844
Provision for loan and lease losses	9,500	8,500	27,750	24,500
Net interest income after provision for loan and lease losses	147,870	141,487	440,043	418,344
Non-interest Income:	'	'	'	'
Deposit service fees	26,489	25,170	77,503	73,786
Loan related fees	5,479	5,840	14,851	15,930
Wealth and investment services	8,762	8,095	26,429	24,781
Mortgage banking activities	1,805	665	3,093	13,584
Increase in cash surrender value of life insurance policies	3,346	3,516	9,900	10,348
Net gain on sale of investment securities	42	269	4,378	708
Impairment loss recognized in earnings	-85	0	-246	0
Other income	5,071	2,702	12,425	7,649
Total non-interest income	50,909	46,257	148,333	146,786
Non-interest Expense:	'	'	'	'
Compensation and benefits	66,849	64,862	198,931	196,680
Occupancy	11,557	11,994	35,807	36,710
Technology and equipment	15,419	14,895	46,166	45,743
Intangible assets amortization	432	1,242	2,269	3,726
Marketing	4,032	3,649	11,461	12,277
Professional and outside services	2,470	2,254	6,441	5,931
Deposit insurance	5,938	5,300	16,814	15,998
Other expense	17,945	18,085	53,955	54,355
Total non-interest expense	124,642	122,281	371,844	371,420
Income before income tax expense	74,137	65,463	216,532	193,710
Income tax expense	23,679	18,158	67,795	57,915
Net income	50,458	47,305	148,737	135,795
Preferred stock dividends	-2,639	-2,639	-7,917	-8,164
Net income available to common shareholders	$47,819	$44,666	$140,820	$127,631
Net income per common share:	'	'	'	'
Basic (in dollars per share)	$0.53	$0.50	$1.56	$1.44
Diluted (in dollars per share)	$0.53	$0.49	$1.55	$1.41

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net income	$50,458	$47,305	$148,737	$135,795
Other comprehensive (loss) income, net of tax	-5,924	6,198	12,630	-26,675
Comprehensive income	$44,534	$53,503	$161,367	$109,120

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Shareholders' Equity (Unaudited) (USD $)	Total	Series A Preferred Stock [Member]	Series E Preferred Stock [Member]	Preferred Stock [Member]	Common Stock [Member]	Paid-In Capital [Member]	Retained Earnings [Member]	Retained Earnings [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]
In Thousands, unless otherwise specified								Series A Preferred Stock [Member]	Series E Preferred Stock [Member]
Beginning Balance at Dec. 31, 2012	$2,093,530	'	'	$151,649	$907	$1,145,620	$1,000,427	'	'	($172,807)	($32,266)
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'	'	'	'
Net income	135,795	'	'	'	'	'	135,795	'	'	'	'
Other comprehensive income (loss), net of tax	-26,675	'	'	'	'	'	'	'	'	'	-26,675
Dividends paid on common stock of $0.55 and $0.40 per share during 9 months ended September 30, 2014 and 2013, respectively	-35,270	'	'	'	'	10	-35,280	'	'	'	'
Dividends paid on preferred stock $63.75 per share on Series A for both 9 months ended September 30, 2014 and 2013 and $1,200.00 and $1,248.89 per share on Series E for 9 months ended September 30, 2014 and 2013, respectively	-8,164	-1,845	-6,319	'	'	'	'	-1,845	-6,319	'	'
Common stock warrants repurchased	-30	'	'	'	'	-30	'	'	'	'	'
Exercise of stock options	984	'	'	'	'	-729	'	'	'	1,713	'
Shares acquired related to employee share-based compensation plans	-381	'	'	'	'	'	'	'	'	-381	'
Stock-based compensation, net of tax impact	7,675	'	'	'	'	2,747	-2,407	'	'	7,335	'
Common stock issued	195	'	'	'	26	-21,274	-36,254	'	'	57,697	'
Ending Balance at Sep. 30, 2013	2,167,659	'	'	151,649	933	1,126,344	1,054,117	'	'	-106,443	-58,941
Beginning Balance at Dec. 31, 2013	2,209,188	'	'	151,649	934	1,125,584	1,080,488	'	'	-100,918	-48,549
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'	'	'	'	'	'	'
Net income	148,737	'	'	'	'	'	148,737	'	'	'	'
Other comprehensive income (loss), net of tax	12,630	'	'	'	'	'	'	'	'	'	12,630
Dividends paid on common stock of $0.55 and $0.40 per share during 9 months ended September 30, 2014 and 2013, respectively	-49,631	'	'	'	'	41	-49,672	'	'	'	'
Dividends paid on preferred stock $63.75 per share on Series A for both 9 months ended September 30, 2014 and 2013 and $1,200.00 and $1,248.89 per share on Series E for 9 months ended September 30, 2014 and 2013, respectively	-7,917	-1,845	-6,072	'	'	'	'	-1,845	-6,072	'	'
Exercise of stock options	1,739	'	'	'	'	-1,517	'	'	'	3,256	'
Common stock repurchased	-10,741	'	'	'	'	'	'	'	'	-10,741	'
Shares acquired related to employee share-based compensation plans	-2,218	'	'	'	'	'	'	'	'	-2,218	'
Stock-based compensation, net of tax impact	8,627	'	'	'	'	3,909	736	'	'	3,982	'
Common stock issued	436	'	'	'	'	436	'	'	'	'	'
Ending Balance at Sep. 30, 2014	$2,310,850	'	'	$151,649	$934	$1,128,453	$1,172,372	'	'	($106,639)	($35,919)

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Shareholders' Equity (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Common Stock, Dividends, Per Share, Declared	$0.55	$0.40
Series A Preferred Stock [Member]	'	'
Preferred Stock, Dividends Per Share, Declared	$63.75	$63.75
Series E Preferred Stock [Member]	'	'
Preferred Stock, Dividends Per Share, Declared	$1,200	$1,248.89

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013
Operating Activities:	'		'
Net income	$148,737		$135,795
Adjustments to reconcile net income to net cash provided by operating activities:	'		'
Provision for loan and lease losses	27,750		24,500
Deferred tax expense	4,388		11,221
Depreciation and amortization	23,509		27,455
Amortization of earning assets and funding premium/discount, net	37,127		50,781
Stock-based compensation	7,793		7,757
Gain on sale, net of write-down, on foreclosed and repossessed assets	-1,059		-1,072
Gain on sale, net of write-down, on premises and equipment	-349		-59
Impairment loss recognized in earnings	246		0
(Gain) loss on alternative investments	-713		354
Loss on fair value adjustment of derivative instruments	585		290
Net gain on the sale of investment securities	-4,378		-708
Increase in cash surrender value of life insurance policies	-9,900		-10,348
Gain from life insurance policies	-671		-1,070
Gain on sale of loans held for sale	-3,093		-13,584
Proceeds from sale of loans held for sale	207,530		670,226
Originations of loans held for sale	-209,585		-592,368
Net (increase) decrease in accrued interest receivable and other assets	-51,113		82,805
Net increase (decrease) in accrued expenses and other liabilities	18,953		-16,743
Net cash provided by operating activities	195,757		375,232
Investing Activities:	'		'
Net (increase) decrease in interest-bearing deposits	-81,720		37,243
Purchases of available-for-sale securities	-92,343		-835,364
Proceeds from maturities and principal payments of available-for-sale securities	317,973		621,385
Proceeds from sales of available-for-sale securities	38,075	[1]	44,261	[1]
Purchases of held-to-maturity securities	-732,767		-702,017
Proceeds from maturities and principal payments of held-to-maturity securities	431,571		587,998
Net purchase of Federal Home Loan Bank stock	-12,296		-3,248
Net increase in loans	-840,342		-503,397
Proceeds from life insurance policies	760		1,768
Proceeds from the sale of foreclosed properties and repossessed assets	7,804		5,741
Proceeds from the sale of premises and equipment	2,641		1,304
Purchases of premises and equipment	-19,908		-11,247
Net cash used for investing activities	-980,552		-755,573
Financing Activities:	'		'
Net increase in deposits	692,498		468,696
Proceeds from Federal Home Loan Bank advances	5,352,931		3,178,120
Repayments of Federal Home Loan Bank advances	-5,115,130		-3,403,245
Net (decrease) increase in securities sold under agreements to repurchase and other borrowings	-94,687		296,130
Issuance of long-term debt	150,000		0
Repayment of long-term debt	-150,000		-102,579
Dividends paid to common shareholders	-49,672		-35,176
Dividends paid to preferred shareholders	-7,917		-8,164
Exercise of stock options	1,739		984
Excess tax benefits from stock-based compensation	1,068		255
Common stock issued	436		195
Common stock repurchased	-10,741		0
Shares acquired related to employee share-based compensation plans	-2,218		-381
Common stock warrants repurchased	0		-30
Net cash provided by financing activities	768,307		394,805
Net (decrease) increase in cash and due from banks	-16,488		14,464
Cash and due from banks at beginning of period	223,616		252,283
Cash and due from banks at end of period	207,128		266,747
Supplemental disclosure of cash flow information:	'		'
Interest paid	69,737		66,582
Income taxes paid	82,155		42,507
Noncash investing and financing activities:	'		'
Transfer of loans and leases, net to foreclosed properties and repossessed assets	$3,289		$9,295
[1]	Proceeds from sales, for the three and nine months ended September 30, 2014, does not include $25.3 million of unsettled sales transactions at September 30, 2014. The gross realized gains and gross realized losses for the three and nine months ended September 30, 2014 reflect the unsettled sales transactions.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Summary of Significant Accounting Policies	'
	Summary of Significant Accounting Policies
	Nature of Operations. Webster Financial Corporation (collectively, with its consolidated subsidiaries, “Webster” or the “Company”) is a financial holding company under the Bank Holding Company Act of 1956, as amended, incorporated under the laws of Delaware in 1986 and headquartered in Waterbury, Connecticut. At September 30, 2014, Webster Financial Corporation's principal asset is all of the outstanding capital stock of Webster Bank, National Association ("Webster Bank").
	Webster, through Webster Bank and various non-banking financial services subsidiaries, delivers financial services to individuals, families and businesses throughout southern New England and into Westchester County, New York. Webster provides business and consumer banking, mortgage lending, financial planning, trust and investment services through banking offices, ATMs, telephone banking, mobile banking and its Internet website (www.websterbank.com). Webster also offers equipment financing, commercial real estate lending, and asset-based lending across the Northeast. Webster Bank offers, through its HSA Bank division, health savings accounts on a nationwide basis.
	Basis of Presentation. The Condensed Consolidated Financial Statements include the accounts of Webster Financial Corporation and all other entities in which it has a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation. Webster's accounting and financial reporting policies conform, in all material respects, to U.S. generally accepted accounting principles (“GAAP”) and to general practices within the financial services industry.
	The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity (“VIE”) under GAAP. Voting interest entities are entities in which the total equity investment at risk is sufficient to enable the entity to finance itself independently and provides the equity holder with the obligation to absorb losses, the right to receive residual returns and the right to make decisions about the entity’s activities. The Company consolidates voting interest entities in which it has at least a majority of the voting interest. VIEs are entities that lack one or more of the characteristics of a voting interest entity. A controlling financial interest in a VIE is present when the Company has both the power and ability to direct the activities of the VIE that most significantly impact the VIE's economic performance and an obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE.
	The Company owns the common stock of a trust which has issued trust preferred securities. The trust is a VIE in which the Company is not the primary beneficiary and, therefore, is not consolidated. The trust's only assets are junior subordinated debentures issued by the Company, which were acquired by the trust using the proceeds from the issuance of the trust preferred securities and common stock. The junior subordinated debentures are included in long-term debt and the Company’s equity interest in the trust is included in other assets in the accompanying Condensed Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is reported in interest expense on long-term debt in the accompanying Condensed Consolidated Statements of Income.
	Certain prior period amounts have been reclassified to conform to the current year's presentation. These reclassifications had no impact on the Company's consolidated financial position, results of operations or net change in cash or cash equivalents.
	Use of Estimates. The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of these Condensed Consolidated Financial Statements. Actual results could differ from those estimates. The allowance for loan and lease losses, the fair value measurements of financial instruments and evaluation of investments for other-than-temporary impairment, the valuation of goodwill, the deferred tax asset valuation allowance, and pension and other postretirement benefits, as well as the status of contingencies, are particularly subject to change.
	Cash Equivalents and Cash Flows. For the purposes of the Condensed Consolidated Statements of Cash Flows, cash equivalents include cash on hand and due from banks and, interest-bearing deposits at the Federal Reserve. Cash equivalents have a maturity of three months or less.
	Cash flows from loans, either originated or acquired, are classified at that time according to management's original intent to either sell or hold the loan for the foreseeable future. When management's intent is to sell the loan, the cash flows of that loan are presented as operating cash flows. When management's intent is to hold the loan for the foreseeable future, the cash flows of that loan are presented as investing cash flows.
	Investment Securities. Investment securities are classified as available-for-sale or held-to-maturity at the time of purchase and any subsequent change to classification is reviewed for compliance with corporate objectives and accounting policy. Debt securities classified as held-to-maturity are those which Webster has the ability and intent to hold to maturity. Securities in the held-to-maturity portfolio are recorded at amortized cost net of unamortized premiums and discounts. Discount accretion income and premium amortization expense are recognized as interest income according to a constant yield methodology. Securities classified as available-for-sale are recorded at fair value with unrealized gains and losses, net of taxes, recorded as a component of other comprehensive income (“OCI”). Securities transferred from available-for-sale to held-to-maturity are recorded at fair value at the time of transfer and the respective gain or loss is recorded as a separate component of OCI and then amortized as an adjustment to interest income over the remaining life of the security.
	All securities classified as available-for-sale or held-to-maturity that are in an unrealized loss position are evaluated for other-than-temporary impairment ("OTTI") on a quarterly basis. The evaluation considers several qualitative factors, including the period of time the security has been in a loss position, in addition to the amount of the unrealized loss. If the Company intends to sell the security or it is more than likely the Company will be required to sell the security prior to recovery of its amortized cost basis, the security is written down to fair value and the loss is recorded in non-interest income in the accompanying Condensed Consolidated Statements of Income. If the Company does not intend to sell the security and it is more likely than not that the Company will not be required to sell the security prior to recovery of its amortized cost basis, only the credit component of any impairment charge to a debt security would be recognized as a loss in non-interest income in the accompanying Condensed Consolidated Statements of Income. The remaining loss component would be recorded to accumulated other comprehensive income ("AOCI"). A decline in the value of an equity security that is considered OTTI is recorded as a loss in non-interest income in the accompanying Condensed Consolidated Statements of Income.
	The specific identification method is used to determine realized gains and losses on sales of securities.
	Loans Held for Sale. Loans typically are classified as held for sale upon origination based on management's intent to sell such loans. Loans held for sale are carried at the lower of cost or fair value. Non-residential mortgage loans held for sale are carried at the lower of cost or fair value and are valued on an individual asset basis. Any cost amount in excess of fair value is recorded as a valuation allowance and recognized as a reduction of other income in the Condensed Consolidated Statements of Income. Gains or losses on the sale of loans held for sale are recorded as non-interest income. Direct loan origination costs and fees are deferred and are recognized as part of the gain or loss at the time of sale.
	Loans. Loans are stated at the principal amount outstanding, net of amounts charged off, unamortized premiums and discounts, and deferred loan fees and/or costs which are recognized as yield adjustments using the interest method. These yield adjustments are amortized over the contractual life of the related loans adjusted for estimated prepayments when applicable. Interest on loans is credited to interest income as earned based on the interest rate applied to principal amounts outstanding.
	Loans are placed on non-accrual status when collection of principal and interest in accordance with contractual terms is doubtful. A loan is transferred to a non-accrual basis generally when principal or interest payments become 90 days delinquent, unless the loan is well secured and in process of collection, or sooner if management concludes circumstances indicate that the borrower may be unable to meet contractual principal or interest payments. Residential real estate and consumer loans are placed on non-accrual status at 90 days past due, or at the date when the Company is notified that the borrower is discharged in bankruptcy. A charge-off is recorded at 180 days if the loan balance exceeds the fair value of the collateral less costs to sell. Commercial, commercial real estate, and equipment finance loans are subject to a detailed review when 90 days past due to determine accrual status, or when payment is uncertain and a specific consideration is made to put a loan or lease on non-accrual status.
	When a loan is placed on non-accrual status, the accrual of interest is discontinued and any unpaid accrued interest is reversed and charged against interest income. If ultimate repayment of a non-accrual loan is expected, any payments received are applied in accordance with contractual terms. If ultimate repayment is not expected on commercial, commercial real estate, and equipment finance loans, any payment received on a non-accrual loan is applied to principal until the unpaid balance has been fully recovered. Any excess is then credited to interest income when received. If the Company determines, through a current valuation analysis, that principal can be repaid on residential real estate and consumer loans, interest payments may be taken into income as received on a cash basis. Except for loans discharged under Chapter 7 of the Bankruptcy Code, loans are removed from non-accrual status when they become current as to principal and interest or demonstrate a period of performance under contractual terms and, in the opinion of management, are fully collectible as to principal and interest. Pursuant to regulatory guidance, a Chapter 7 discharged bankruptcy loan is removed from non-accrual status when the bank expects full repayment of the remaining pre-discharged contractual principal and interest, is a closed-end amortizing loan, fully collateralized, and post-discharge had at least six consecutive months of current payments.
	Allowance for Loan and Lease Losses. The allowance for loan and lease losses ("ALLL") is a reserve established through a provision for loan and lease losses charged to expense and represents management’s best estimate of probable losses that may be incurred within the existing loan and lease portfolio as of the balance sheet date. The level of the allowance reflects management’s view of trends in losses, current portfolio quality, and present economic, political, and regulatory conditions. Portions of the allowance may be allocated for specific loans and leases; however, the entire allowance is available for any loan or lease that is charged off. A charge-off is recorded on a case-by-case basis when all or a portion of the loan or lease is deemed to be uncollectible. Back-testing is performed to compare original estimated losses and actual observed losses, resulting in ongoing refinements. While management utilizes its best judgment based on the information available at the time, the ultimate adequacy of the allowance is dependent upon a variety of factors that are beyond the Company’s control, which include the performance of the Company’s portfolio, economic conditions, interest rate sensitivity, and the view of the regulatory authorities regarding loan classifications.
	The ALLL consists of the following three elements: (i) specific valuation allowances established for probable losses on impaired loans and leases; (ii) quantitative valuation allowances calculated using loss experience for like loans and leases with similar characteristics and trends, adjusted, as necessary, to reflect the impact of current conditions; and (iii) qualitative factors determined based on general economic conditions and other factors that may be internal or external to the Company.
	Loans and leases are considered impaired when, based on current information and events, it is probable the Company will be unable to collect all amounts due in accordance with the original contractual terms of the loan agreement, including scheduled principal and interest payments. Impairment is evaluated on a pooled basis for smaller-balance homogeneous residential and consumer loans. Commercial, commercial real estate, and equipment financing loans and leases over a specific dollar amount and all troubled debt restructurings ("TDR") are evaluated individually for impairment. A loan identified as a TDR is considered an impaired loan for the entire term of the loan, with few exceptions. If a loan is impaired, a specific valuation allowance may be established, and the loan is reported net, at the present value of estimated future cash flows using the loan’s original interest rate or at the fair value of collateral less cost to sell if repayment is expected from collateral liquidation. Interest payments on non-accruing impaired loans are typically applied to principal unless collectability of the principal amount is reasonably assured, in which case interest is recognized on a cash basis. Impaired loans, or portions thereof, are charged off when deemed uncollectible. Factors considered by management in determining impairment include payment status, collateral value, discharged bankruptcy, and the likelihood of collecting scheduled principal and interest payments. Consumer modified loans are analyzed for re-default probability, which is considered when determining the impaired reserve for ALLL. The current or weighted average (for multiple notes within a commercial borrowing arrangement) interest rate of the loan is used as the discount rate when the interest rate floats with a specified index. A change in terms or payments would be included in the impairment calculation.
	Reserve for Unfunded Commitments. The reserve for unfunded commitments provides for probable losses inherent with funding the unused portion of legal commitments available to lend. The unfunded reserve calculation includes factors that are consistent with ALLL methodology for funded loans using the loss given default, probability of default and a draw down factor applied to the underlying borrower risk and facility grades. Changes in the reserve for unfunded credit commitments, included within other liabilities, are reported as a component of other expense in the accompanying Condensed Consolidated Statements of Income.
	Troubled Debt Restructurings. A modified loan is considered a TDR when the following two conditions are met: (i) the borrower is experiencing financial difficulties and (ii) the modification constitutes a concession. The Company considers all aspects of the restructuring in determining whether a concession has been granted, including the debtor's ability to access funds at a market rate. In general, a concession exists when the modified terms of the loan are more attractive to the borrower than standard market terms. Modified terms are dependent upon the financial position and needs of the individual borrower. The most common types of modifications include covenant modifications, forbearance and/or other concessions. Loans for which the borrower has been discharged under Chapter 7 bankruptcy are considered collateral dependent TDRs, impaired at the date of discharge, and charged down to the fair value of collateral less cost to sell, if management considers that loss potential likely exists.
	The Company’s policy is to place consumer loan TDRs, except those that were performing prior to TDR status, on non-accrual status for a minimum period of six months. Commercial TDRs are evaluated on a case-by-case basis for determination of whether or not to place on non-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. Initially, all TDRs are reported as impaired. Generally, TDRs are classified as impaired loans and reported as TDRs for the remaining life of the loan. Impaired and TDR classification, may be removed if the borrower demonstrates compliance with the modified terms for a minimum of six months and through one fiscal year-end and the restructuring agreement specifies a market rate of interest equal to that which would be provided to a borrower with similar credit at the time of restructuring. In the limited circumstance that a loan is removed from TDR classification it is the Company’s policy to continue to base its measure of loan impairment on the contractual terms specified by the loan agreement.
	Transfers and Servicing of Financial Assets. Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is generally considered to have been surrendered when (i) the transferred assets are legally isolated from the Company or its consolidated affiliates, even in bankruptcy or other receivership, (ii) the transferee has the right to pledge or exchange the assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Company, and (iii) the Company does not maintain the obligation or unilateral ability to reclaim or repurchase the assets.
	The Company sells financial assets in the normal course of business, the majority of which are residential mortgage loan sales primarily to government-sponsored enterprises through established programs, commercial loan sales through participation agreements, and other individual or portfolio loan and securities sales. In accordance with accounting guidance for asset transfers, the Company considers any ongoing involvement with transferred assets in determining whether the assets can be derecognized from the balance sheet. With the exception of servicing and certain performance-based guarantees, the Company’s continuing involvement with financial assets sold is minimal and generally limited to market customary representation and warranty clauses.
	When the Company sells financial assets, it may retain servicing rights and/or other interests in the financial assets. The gain or loss on sale depends on the previous carrying amount of the transferred financial assets and the consideration received and any liabilities incurred in exchange for the transferred assets. Upon transfer, any servicing assets and other interests held by the Company are carried at the lower of cost or fair value.
	Recently Adopted Accounting Standards Updates
	ASU No. 2013-11 - Income Taxes (Topic 740) - "Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force)." The ASU requires an entity to present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward, as applicable. To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit shall be presented in the financial statements as a liability and shall not be combined with deferred tax assets. This update was adopted effective January 1, 2014 and will be applied prospectively; however, its netting provisions are consistent with the Company’s previous presentation, as applicable, and as a result do not require additional disclosures.
	Recently Issued Accounting Standards Updates
	ASU No. 2014-01 - Investments - Equity Method and Joint Ventures (Topic 323) - "Accounting for Investments in Qualified Affordable Housing Projects (a consensus of the FASB Emerging Issues Task Force)." The ASU permits an entity to make an accounting policy election to account for its investment in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportionate amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). The decision to apply the proportionate amortization method of accounting should be applied consistently to all qualifying affordable housing project investments. A reporting entity that uses the effective yield or other method to account for its investments in qualified affordable housing projects before the date of adoption may continue to apply such method to those preexisting investments. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-04, Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - "Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure (a consensus of the FASB Emerging Issues Task Force)." The ASU clarifies that an in substance repossession or foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (i) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (ii) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar agreement. In addition, the amendments require disclosure of both the amount of foreclosed residential real estate property held by the creditor and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure in accordance with local requirements of the applicable jurisdiction. An entity can elect to adopt the amendments using either a modified retrospective method or a prospective transition method. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-09 - Revenue from Contracts with Customers (Topic 606). The ASU establishes a single comprehensive model for an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled, and will supersede nearly all existing revenue recognition guidance, to clarify and converge revenue recognition principles under US GAAP and IFRS. The update outlines five steps to recognizing revenue: (i) identify the contracts with the customer; (ii) identify the separate performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the separate performance obligations; (v) recognize revenue when each performance obligation is satisfied. The update requires more comprehensive disclosures, relating to quantitative and qualitative information for amounts, timing, the nature and uncertainty of revenue, and cash flows arising from contracts with customers, which will mainly impact construction and high-tech industries. The most significant potential impact to banking entities relates to less prescriptive derecognition requirements on the sale of OREO property. The amendments are effective for annual and interim periods beginning after January 1, 2017. An entity may elect either a full retrospective or a modified retrospective application. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-11 - Transfers and Servicing (Topic 860) - “Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures.” The ASU requires two accounting changes: (i) the accounting for repurchase-to-maturity transactions are to be accounted for as secured borrowings; (ii) repurchase financing arrangements, separate accounting is required for a transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty, which will result in secured borrowing accounting for the repurchase agreement. Additionally, disclosure requirements have been expanded to include a disaggregation of collateral used for secured borrowings, and contractual maturity disclosure has been expanded to interim periods. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-12, Compensation-Stock Compensation (Topic 718) - “Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period (a consensus of the FASB Emerging Issues Task Force).” The ASU provides explicit guidance to account for a performance target that could be achieved after the requisite service period as a performance condition. For awards within the scope of this Update, the Task Force decided that an entity should apply existing guidance in Topic 718 as it relates to share-based payments with performance conditions that affect vesting. Consistent with that guidance, performance conditions that affect vesting should not be reflected in estimating the fair value of an award at the grant date. Compensation cost should be recognized when it is probable that the performance target will be achieved and should represent the compensation cost attributable to the period for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The amendments are effective for annual and interim periods beginning after January 1, 2016. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-14, Receivables-Troubled Debt Restructurings by Creditors (Subtopic 310-40) - "Classification of Certain Government-Guaranteed Residential Mortgage Loans upon Foreclosure (a consensus of the FASB Emerging Issues Task Force)." The ASU has been issued to reduce diversity in practice in the classification of foreclosed residential mortgage loans held by creditors that are fully guaranteed under certain government programs, including the Federal Housing Administration guarantees. A residential mortgage loan would be derecognized and a separate other receivable would be recognized upon foreclosure if the loan has both of the following characteristics: (i) the loan has a government guarantee that is not separable from the loan before foreclosure entitling the creditor to the full unpaid principal balance of the loan; and (ii) at the time of foreclosure, the creditor has the intent to make a claim on the guarantee and the ability to recover the full unpaid principal balance of the loan through the guarantee. Notably, upon foreclosure, the separate other receivable would be measured based on the current amount of the loan balance expected to be recovered under the guarantee. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40) - "Disclosure of Uncertainties About an Entity's Ability to Continue as a Going Concern." The ASU has been issued to require an entity to evaluate going concern uncertainties by assessing information about conditions and events that exist at the date the financial statements are issued and provide footnote disclosures when it is either (i) more likely than not that the entity will be unable to meet its obligations within twelve months after the financial statement date without taking actions outside the ordinary course of business, or (ii) known or probable that the entity will be unable to meet its obligations within twenty-four months after the financial statement date without taking actions outside the ordinary course of business. The amendments are effective for annual periods beginning after January 1, 2017 and also for interim periods beginning after January 1, 2018. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.

Investment_Securities

Investment Securities	9 Months Ended
	Sep. 30, 2014
Investments, Debt and Equity Securities [Abstract]	'
Investment Securities	'
	Investment Securities
	Summaries of the amortized cost, carrying value, and fair value of Webster’s investment securities are presented below:
		At September 30, 2014
					Recognized in OCI									Not Recognized in OCI
	(In thousands)	Amortized			Gross			Gross			Carrying			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized			Value			Unrealized			Unrealized
					Gains			Losses						Gains			Losses
	Available-for-sale:
	U.S. Treasury Bills	$	525		$	—		$	—		$	525		$	—		$	—		$	525
	Agency collateralized mortgage obligations (“CMO”)	628,737			10,543			(1,057		)	638,223			—			—			638,223
	Agency mortgage-backed securities (“MBS”)	1,103,345			11,014			(23,539		)	1,090,820			—			—			1,090,820
	Agency commercial mortgage-backed securities (“ACMBS”)	80,732			—			(349		)	80,383			—			—			80,383
	Commercial mortgage-backed securities (“CMBS”)	510,922			21,975			(55		)	532,842			—			—			532,842
	Collateralized loan obligations ("CLO") (1)	379,741			912			(142		)	380,511			—			—			380,511
	Pooled trust preferred securities	—			—			—			—			—			—			—
	Single issuer trust preferred securities	41,936			83			(2,637		)	39,382			—			—			39,382
	Corporate debt securities	107,132			4,068			—			111,200			—			—			111,200
	Equity securities - financial institutions	—			—			—			—			—			—			—
	Total available-for-sale	$	2,853,070		$	48,595		$	(27,779	)	$	2,873,886		$	—		$	—		$	2,873,886
	Held-to-maturity:
	Agency CMO	$	411,128		$	—		$	—		$	411,128		$	7,374		$	(1,409	)	$	417,093
	Agency MBS	2,181,225			—			—			2,181,225			52,799			(23,068		)	2,210,956
	Agency CMBS	377,382			—			—			377,382			650			(622		)	377,410
	Municipal bonds and notes	377,074			—			—			377,074			15,332			(38		)	392,368
	CMBS	288,692			—			—			288,692			8,833			(2,122		)	295,403
	Private Label MBS	6,478			—			—			6,478			117			—			6,595
	Total held-to-maturity	$	3,641,979		$	—		$	—		$	3,641,979		$	85,105		$	(27,259	)	$	3,699,825
	-1	Amortized cost is net of $2.8 million of other-than-temporary impairments at September 30, 2014.
		At December 31, 2013
					Recognized in OCI									Not Recognized in OCI
	(In thousands)	Amortized			Gross			Gross			Carrying			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized			Value			Unrealized			Unrealized
					Gains			Losses						Gains			Losses
	Available-for-sale:
	U.S. Treasury Bills	$	325		$	—		$	—		$	325		$	—		$	—		$	325
	Agency CMO	794,397			14,383			(1,868		)	806,912			—			—			806,912
	Agency MBS	1,265,276			9,124			(47,698		)	1,226,702			—			—			1,226,702
	Agency CMBS	71,759			—			(782		)	70,977			—			—			70,977
	CMBS	436,872			28,398			(996		)	464,274			—			—			464,274
	CLO (1)	357,326			315			—			357,641			—			—			357,641
	Pooled trust preferred securities (2)	31,900			—			(3,410		)	28,490			—			—			28,490
	Single issuer trust preferred securities	41,807			—			(6,872		)	34,935			—			—			34,935
	Corporate debt securities	108,936			4,155			—			113,091			—			—			113,091
	Equity securities - financial institutions (3)	2,314			1,270			—			3,584			—			—			3,584
	Total available-for-sale	$	3,110,912		$	57,645		$	(61,626	)	$	3,106,931		$	—		$	—		$	3,106,931
	Held-to-maturity:
	Agency CMO	$	365,081		$	—		$	—		$	365,081		$	10,135		$	(1,009	)	$	374,207
	Agency MBS	2,130,685			—			—			2,130,685			43,315			(53,188		)	2,120,812
	Agency CMBS	115,995			—			—			115,995			44			(818		)	115,221
	Municipal bonds and notes	448,405			—			—			448,405			11,104			(1,228		)	458,281
	CMBS	290,057			—			—			290,057			8,635			(4,975		)	293,717
	Private Label MBS	8,498			—			—			8,498			176			—			8,674
	Total held-to-maturity	$	3,358,721		$	—		$	—		$	3,358,721		$	73,409		$	(61,218	)	$	3,370,912
	-1	Amortized cost is net of $2.6 million of other-than-temporary impairments at December 31, 2013.
	-2	Amortized cost is net of $14.0 million of other-than-temporary impairments at December 31, 2013.
	-3	Amortized cost is net of $20.4 million of other-than-temporary impairments at December 31, 2013.
	Contractual Maturities
	The amortized cost and fair value of debt securities at September 30, 2014, by contractual maturity, are set forth below:
		Available-for-Sale							Held-to-Maturity
	(In thousands)	Amortized			Fair				Amortized			Fair
		Cost			Value				Cost			Value
	Due in one year or less	$	15,518		$	15,546			$	15		$	15
	Due after one year through five years	107,131			111,200				70,092			73,095
Due after five through ten years	260,350			260,884				67,799			70,457
Due after ten years	2,470,071			2,486,256				3,504,073			3,556,258
Total debt securities	$	2,853,070		$	2,873,886			$	3,641,979		$	3,699,825
For the maturity schedule above, mortgage-backed securities and collateralized loan obligations, which are not due at a single maturity date, have been categorized based on the maturity date of the underlying collateral. Actual principal cash flows may differ from this maturity date presentation because borrowers have the right to prepay obligations with or without prepayment penalties. At September 30, 2014, the Company had a carrying value of $818.0 million in callable securities in its CMBS, CLO, and municipal bond portfolios. The Company considers these factors in the evaluation of its interest rate risk profile and effective duration. These maturities do not reflect actual duration which is impacted by prepayment assumptions.
Securities with a carrying value totaling $2.9 billion at September 30, 2014 and $2.7 billion at December 31, 2013 were pledged to secure public funds, trust deposits, repurchase agreements and for other purposes, as required or permitted by law. At September 30, 2014 and December 31, 2013, the Company had no investments in obligations of individual states, counties, or municipalities which exceeded 10% of consolidated shareholders’ equity.
Gross Unrealized Losses and Fair Value
The following tables provide information on the gross unrealized losses and fair value of the Company’s investment securities with unrealized losses that are not deemed to be other-than-temporarily impaired, aggregated by investment security type and length of time that individual investment securities have been in a continuous unrealized loss position:
	At September 30, 2014
	Less Than Twelve Months							Twelve Months or Longer							Total
(Dollars in thousands)	Fair			Unrealized				Fair			Unrealized				# of	Fair			Unrealized
	Value			Losses				Value			Losses				Holdings	Value			Losses
Available-for-sale:
Agency CMO	$	82,646		$	(278	)		$	35,915		$	(779	)		10	$	118,561		$	(1,057	)
Agency MBS	55,408			(262		)		665,932			(23,277		)		73	721,340			(23,539		)
Agency CMBS	36,325			(88		)		44,057			(261		)		4	80,382			(349		)
CMBS	15,000			(41		)		9,390			(14		)		3	24,390			(55		)
CLO	31,858			(142		)		—			—				2	31,858			(142		)
Pooled trust preferred securities	—			—				—			—				—	—			—
Single issuer trust preferred securities	—			—				35,120			(2,637		)		7	35,120			(2,637		)
Total available-for-sale in an unrealized loss position	$	221,237		$	(811	)		$	790,414		$	(26,968	)		99	$	1,011,651		$	(27,779	)
Held-to-maturity:
Agency CMO	$	111,069		$	(798	)		$	25,943		$	(611	)		10	$	137,012		$	(1,409	)
Agency MBS	258,608			(1,161		)		671,769			(21,907		)		64	930,377			(23,068		)
Agency CMBS	196,139			(622		)		—			—				9	196,139			(622		)
Municipal bonds and notes	4,311			(6		)		3,075			(32		)		14	7,386			(38		)
CMBS	5,494			(10		)		73,167			(2,112		)		8	78,661			(2,122		)
Total held-to-maturity in an unrealized loss position	$	575,621		$	(2,597	)		$	773,954		$	(24,662	)		105	$	1,349,575		$	(27,259	)
	At December 31, 2013
	Less Than Twelve Months							Twelve Months or Longer							Total
(Dollars in thousands)	Fair			Unrealized				Fair			Unrealized				# of	Fair			Unrealized
	Value			Losses				Value			Losses				Holdings	Value			Losses
Available-for-sale:
Agency CMO	$	149,894		$	(1,713	)		$	9,011		$	(155	)		15	$	158,905		$	(1,868	)
Agency MBS	616,286			(29,537		)		279,680			(18,161		)		88	895,966			(47,698		)
Agency CMBS	70,977			(782		)		—			—				3	70,977			(782		)
CMBS	52,340			(996		)		—			—				7	52,340			(996		)
CLO	—			—				—			—				—	—			—
Pooled trust preferred securities	—			—				11,141			(3,410		)		2	11,141			(3,410		)
Single issuer trust preferred securities	3,777			(381		)		31,158			(6,491		)		8	34,935			(6,872		)
Total available-for-sale in an unrealized loss position	$	893,274		$	(33,409	)		$	330,990		$	(28,217	)		123	$	1,224,264		$	(61,626	)
Held-to-maturity:
Agency CMO	$	53,789		$	(1,009	)		$	—		$	—			4	$	53,789		$	(1,009	)
Agency MBS	1,045,693			(42,181		)		170,780			(11,007		)		94	1,216,473			(53,188		)
Agency CMBS	90,218			(818		)		—			—				4	90,218			(818		)
Municipal bonds and notes	46,587			(1,193		)		2,166			(35		)		51	48,753			(1,228		)
CMBS	106,527			(4,059		)		14,832			(916		)		11	121,359			(4,975		)
Total held-to-maturity in an unrealized loss position	$	1,342,814		$	(49,260	)		$	187,778		$	(11,958	)		164	$	1,530,592		$	(61,218	)
Available-for-Sale Impairment Analysis
The following discussion summarizes, by investment security type, the basis for evaluating if the applicable investment securities within the Company’s available-for-sale portfolio were other-than-temporarily impaired at September 30, 2014. Unless otherwise noted for an investment security type, management does not intend to sell these investments and has determined, based upon available evidence, that it is more likely than not that the Company will not be required to sell these securities before the recovery of its amortized cost.
Agency collateralized mortgage obligations (CMO) – There were unrealized losses of $1.1 million on the Company’s investment in agency CMO at September 30, 2014, compared to $1.9 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. The contractual cash flows for these investments are performing as expected and there has been no change in the underlying credit quality. As such, the Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Agency mortgage-backed securities (MBS) – There were unrealized losses of $23.5 million on the Company’s investment in residential mortgage-backed securities issued by government agencies at September 30, 2014, compared to $47.7 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. These investments are issued by a government or a government sponsored agency and therefore are backed by certain government guarantees, either direct or indirect. There has been no change in the credit quality and the contractual cash flows are performing as expected. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Agency commercial mortgage-backed securities (ACMBS) - There were unrealized losses of $0.3 million on the Company's investment in commercial mortgage-backed securities issued by government agencies at September 30, 2014, compared to $0.8 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Commercial mortgage-backed securities (CMBS) – There were unrealized losses of $55 thousand on the Company’s investment in commercial mortgage-backed securities issued by entities other than government agencies at September 30, 2014, compared to $1.0 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. Internal and external metrics are considered when evaluating potential OTTI. Internal stress tests are performed on individual bonds to monitor potential losses under stress scenarios. In addition, market analytics are performed to validate internal results. Contractual cash flows for the bonds continue to perform as expected. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Collateralized loan obligations (CLO) – There were unrealized losses of $142 thousand on the Company’s investment in Volcker compliant collateralized loan obligations at September 30, 2014 compared to no unrealized losses at December 31, 2013. The unrealized losses increased due to increased CLO spreads during the period. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014. The Company continues to recognize the full write down of CLO positions to market value if they meet the definition of a covered fund under the Volcker Rule effective December 10, 2013.
Pooled trust preferred securities – There were no unrealized losses on the Company's investment in pooled trust preferred securities at September 30, 2014, compared to $3.4 million at December 31, 2013. The decrease in unrealized loss is due to the sale of the remaining two non-investment grade pooled trust preferred securities during the third quarter of 2014. The Company does not hold investments in pooled trust preferred securities at September 30, 2014.
Single issuer trust preferred securities - There were unrealized losses of $2.6 million on the Company's investment in single issuer trust preferred securities at September 30, 2014, compared to $6.9 million at December 31, 2013. Unrealized losses decreased due to lower market spreads which resulted in higher security prices since December 31, 2013. The single issuer portfolio consists of four investments issued by three large capitalization money center financial institutions, which continue to service the debt. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Corporate debt securities – There were no unrealized losses on the Company’s investment in corporate debt securities at September 30, 2014 and December 31, 2013. These securities are currently performing as expected at September 30, 2014.
Equity securities - financial institutions – There were no unrealized losses on the Company’s investment in equity securities at September 30, 2014 and December 31, 2013. The equity portfolio was sold at a gain during the current quarter. The Company does not hold investments in equity securities at September 30, 2014.
Held-to-Maturity Impairment Analysis
The following discussion summarizes, by investment type, the basis for the conclusion that the applicable investment securities within the Company’s held-to-maturity portfolio were not other-than-temporarily impaired at September 30, 2014. Unless otherwise noted under an investment security type, management does not intend to sell these investments and has determined, based upon available evidence, that it is more likely than not that the Company will not be required to sell these securities before the recovery of its amortized cost.
Agency CMO – There were unrealized losses of $1.4 million on the Company’s investment in agency CMO at September 30, 2014, compared to $1.0 million at December 31, 2013. Unrealized losses increased due to higher market rates on CMO purchased during the quarter. The contractual cash flows for these investments are performing as expected and there has been no change in the underlying credit quality. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Agency mortgage-backed securities (MBS) – There were unrealized losses of $23.1 million on the Company’s investment in residential mortgage-backed securities issued by government agencies at September 30, 2014, compared to $53.2 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. These investments are issued by a government or a government sponsored agency and therefore are backed by certain government guarantees, either direct or indirect. There has been no change in the credit quality and the contractual cash flows are performing as expected. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Agency commercial mortgage-backed securities (ACMBS) - There were unrealized losses of $0.6 million on the Company’s investment in commercial mortgage-backed securities issued by government agencies at September 30, 2014, compared to $0.8 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Municipal bonds and notes – There were unrealized losses of $38 thousand on the Company’s investment in municipal bonds and notes at September 30, 2014, compared to $1.2 million at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. The municipal portfolio is primarily comprised of bank qualified bonds, over 99.3% with credit ratings of A or better. In addition, the portfolio is comprised of 86.0% general obligation bonds, 13.5% revenue bonds, and 0.5% other bonds. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Commercial mortgage-backed securities (CMBS) – There were unrealized losses of $2.1 million on the Company’s investment in commercial mortgage-backed securities issued by entities other than government agencies at September 30, 2014, compared to $5.0 million unrealized losses at December 31, 2013. Unrealized losses decreased due to lower market rates which resulted in higher security prices since December 31, 2013. Internal and external metrics are considered when evaluating potential OTTI. Internal stress tests are performed on individual bonds to monitor potential losses under stress scenarios. In addition, market analytics are performed to validate internal results. The contractual cash flows for these investments are performing as expected. The Company does not consider these securities to be other-than-temporarily impaired at September 30, 2014.
Private Label MBS - There were no unrealized losses on the Company's investment in private label residential mortgage-backed securities issued by entities other than government agencies at September 30, 2014 and December 31, 2013. These securities are currently performing as expected at September 30, 2014.
Other-Than-Temporary Impairment
There were additions to OTTI of $85 thousand and $246 thousand for the three and nine months ended September 30, 2014, respectively, and no additions for the three and nine months ended September 30, 2013. The cumulative OTTI related to previously impaired securities was reduced due to the sale of four trust preferred securities during the first quarter of 2014, and the sale of two trust preferred securities and refinancing of two CLO during the third quarter of 2014. To the extent that changes in interest rates, credit movements, and other factors that influence the fair value of investments occur, the Company may be required to record impairment charges for OTTI in future periods.
The following is a roll forward of the amount of OTTI related to debt securities:
	Three months ended September 30,								Nine months ended September 30,
(In thousands)	2014				2013				2014				2013
Balance of OTTI, beginning of period	$	9,738			$	10,460			$	16,633			$	10,460
Reduction for securities sold, called	(7,026		)		(1,104		)		(14,082		)		(1,104		)
Additions for OTTI not previously recognized	85				—				246				—
Balance of OTTI, end of period	$	2,797			$	9,356			$	2,797			$	9,356
Realized Gains and Losses
The following table summarizes proceeds from available-for-sale securities, the gross realized gains and losses from those sales, and the impact of the recognition of other-than-temporary impairments for the periods presented:
	Three months ended September 30,								Nine months ended September 30,
(In thousands)	2014				2013				2014				2013
Proceeds from sales(1)	$	16,380			$	7,740			$	38,075			$	44,261
Gross realized gains	$	1,812			$	269			$	6,148			$	708
Gross realized losses	(1,770		)		—				(1,770		)		—
OTTI write-down	(85		)		—				(246		)		—
Net realized (losses) gains from investment securities	$	(43	)		$	269			$	4,132			$	708
-1	Proceeds from sales, for the three and nine months ended September 30, 2014, does not include $25.3 million of unsettled sales transactions at September 30, 2014. The gross realized gains and gross realized losses for the three and nine months ended September 30, 2014 reflect the unsettled sales transactions.

Loans_and_Leases

Loans and Leases	9 Months Ended
	Sep. 30, 2014
Loans and Leases Receivable Disclosure [Abstract]	'
Loans and Leases	'
	Loans and Leases
	Recorded Investment in Loans and Leases. The following tables summarize the recorded investment in loans and leases by portfolio segment:
		At September 30, 2014
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Total (2)
											Real Estate (1)			Financing
	Recorded Investment:
	Individually evaluated for impairment	$	144,355		$	51,503		$	41,329		$	100,560		$	1,759		$	339,506
	Collectively evaluated for impairment	3,321,447			2,538,505			3,602,406			3,261,898			488,391			13,212,647
	Recorded investment in loans and leases	3,465,802			2,590,008			3,643,735			3,362,458			490,150			13,552,153
	Less: Accrued interest	10,448			8,108			11,744			8,351			—			38,651
	Loans and leases	$	3,455,354		$	2,581,900		$	3,631,991		$	3,354,107		$	490,150		$	13,513,502
		At December 31, 2013
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Total (2)
											Real Estate (1)			Financing
	Recorded Investment:
	Individually evaluated for impairment	$	142,871		$	52,179		$	52,199		$	105,046		$	210		$	352,505
	Collectively evaluated for impairment	3,228,688			2,492,353			3,241,045			2,961,378			460,240			12,383,704
	Recorded investment in loans and leases	3,371,559			2,544,532			3,293,244			3,066,424			460,450			12,736,209
	Less: Accrued interest	10,134			7,844			10,393			8,062			—			36,433
	Loans and leases	$	3,361,425		$	2,536,688		$	3,282,851		$	3,058,362		$	460,450		$	12,699,776
	-1	Includes certain loans individually evaluated for impairment under the Company's loan policy that were deemed not to be impaired at both September 30, 2014 and December 31, 2013.
	-2	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.
	At September 30, 2014, the Company had pledged $5.4 billion of eligible loan collateral to support available borrowing capacity at the Federal Home Loan Bank of Boston ("FHLB") and the Federal Reserve Bank of Boston.
	Loans and Leases Portfolio Aging. The following tables summarize the aging of the recorded investment in loans and leases by portfolio class:
		At September 30, 2014
	(In thousands)	30-59 Days			60-89 Days			> 90 Days Past Due			Non-accrual			Total Past Due and Non-accrual			Current			Total Loans
		Past Due and			Past Due and			and Accruing												and Leases
		Accruing			Accruing
	Residential: (1)	$	9,906		$	6,295		$	—		$	68,402		$	84,603		$	3,381,199		$	3,465,802
	Consumer:
	Home equity (1)	9,498			7,068			—			38,959			55,525			2,429,571			2,485,096
	Other consumer	671			334			—			244			1,249			103,663			104,912
	Commercial:
	Commercial non-mortgage	8,402			450			795			12,454			22,101			2,972,897			2,994,998
	Asset-based	—			—			—			—			—			648,737			648,737
	Commercial real estate:
	Commercial real estate	991			670			488			14,443			16,592			3,131,467			3,148,059
	Commercial construction	—			—			—			3,919			3,919			210,480			214,399
	Equipment financing	241			192			—			1,659			2,092			488,058			490,150
	Total	$	29,709		$	15,009		$	1,283		$	140,080		$	186,081		$	13,366,072		$	13,552,153
	-1	A total of $17.6 million residential and consumer loans was reclassified from non-accrual to accrual status as a result of updated regulatory guidance issued in the first quarter of 2014.
		At December 31, 2013
	(In thousands)	30-59 Days			60-89 Days			> 90 Days Past Due			Non-accrual			Total Past Due and Non-accrual			Current			Total Loans
		Past Due and			Past Due and			and Accruing												and Leases
		Accruing			Accruing
	Residential:	$	11,721		$	6,839		$	—		$	81,520		$	100,080		$	3,271,479		$	3,371,559
	Consumer:
	Home equity	15,332			5,120			—			51,788			$	72,240		2,410,953			$	2,483,193
	Other consumer	462			193			—			140			795			60,543			61,338
	Commercial:
	Commercial non-mortgage	3,208			984			4,305			10,946			19,443			2,712,870			2,732,313
	Asset-based	—			—			—			—			—			560,931			560,931
	Commercial real estate:
	Commercial real estate	4,387			587			235			13,456			18,665			2,842,637			2,861,302
	Commercial construction	—			—			—			4,237			4,237			200,886			205,123
	Equipment financing	299			63			—			1,141			1,503			458,947			460,450
	Total	$	35,409		$	13,786		$	4,540		$	163,228		$	216,963		$	12,519,246		$	12,736,209
	Interest on non-accrual loans and leases that would have been recorded as additional interest income for the three and nine months ended September 30, 2014 and 2013, had the loans and leases been current in accordance with their original terms, totaled $3.0 million and $7.6 million and $3.5 million and $10.9 million, respectively.
	Allowance for Loan and Lease Losses. The following tables summarize the ALLL by portfolio segment:
		At or for the three months ended September 30, 2014
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
											Real Estate			Financing
	Allowance for loan and lease losses:
Balance, beginning of period	$	19,054		$	33,867		$	51,632		$	34,144		$	5,539		$	10,632		$	154,868
Provision (benefit) charged to expense	2,006			5,357			2,051			68			344			(326		)	9,500
Losses charged off	(1,870		)	(6,329		)	(2,738		)	(139		)	(491		)	—			(11,567		)
Recoveries	261			1,947			1,017			120			336			—			3,681
Balance, end of period	$	19,451		$	34,842		$	51,962		$	34,193		$	5,728		$	10,306		$	156,482
Individually evaluated for impairment	$	11,501		4,165			$	1,717		3,818			$	29		$	—		$	21,230
Collectively evaluated for impairment	$	7,950		$	30,677		$	50,245		$	30,375		$	5,699		$	10,306		$	135,252
	At or for the three months ended September 30, 2013
(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
										Real Estate			Financing
Allowance for loan and lease losses:
Balance, beginning of period	$	26,876		$	49,659		$	43,847		$	28,457		$	3,603		$	11,000		$	163,442
Provision (benefit) charged to expense	1,075			(1,732		)	3,783			6,046			(672		)	—			8,500
Losses charged off	(3,800		)	(5,827		)	(3,245		)	(4,069		)	(10		)	—			(16,951		)
Recoveries	152			1,188			426			105			683			—			2,554
Balance, end of period	$	24,303		$	43,288		$	44,811		$	30,539		$	3,604		$	11,000		$	157,545
Individually evaluated for impairment	$	13,003		$	3,281		$	1,630		$	5,397		$	—		$	—		$	23,311
Collectively evaluated for impairment	$	11,300		$	40,007		$	43,181		$	25,142		$	3,604		$	11,000		$	134,234
	At or for the nine months ended September 30, 2014
(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
										Real Estate			Financing
Allowance for loan and lease losses:
Balance, beginning of period	$	20,580		$	39,551		$	47,706		$	29,883		$	3,912		$	10,941		$	152,573
Provision (benefit) charged to expense	2,711			7,530			10,716			6,633			795			(635		)	27,750
Losses charged off	(4,868		)	(16,501		)	(9,571		)	(2,991		)	(511		)	—			(34,442		)
Recoveries	1,028			4,262			3,111			668			1,532			—			10,601
Balance, end of period	$	19,451		$	34,842		$	51,962		$	34,193		$	5,728		$	10,306		$	156,482
Individually evaluated for impairment	$	11,501		$	4,165		$	1,717		$	3,818		$	29		$	—		$	21,230
Collectively evaluated for impairment	$	7,950		$	30,677		$	50,245		$	30,375		$	5,699		$	10,306		$	135,252
	At or for the nine months ended September 30, 2013
(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
										Real Estate			Financing
Allowance for loan and lease losses:
Balance, beginning of period	$	29,474		$	54,254		$	46,566		$	30,834		$	4,001		$	12,000		$	177,129
Provision (benefit) charged to expense	2,835			7,328			8,902			9,146			(2,711		)	(1,000		)	24,500
Losses charged off	(8,848		)	(23,565		)	(13,740		)	(10,339		)	(101		)	—			(56,593		)
Recoveries	842			5,271			3,083			898			2,415			—			12,509
Balance, end of period	$	24,303		$	43,288		$	44,811		$	30,539		$	3,604		$	11,000		$	157,545
Individually evaluated for impairment	$	13,003		$	3,281		$	1,630		$	5,397		$	—		$	—		$	23,311
Collectively evaluated for impairment	$	11,300		$	40,007		$	43,181		$	25,142		$	3,604		$	11,000		$	134,234
Impaired Loans and Leases. The following tables summarize impaired loans and leases by portfolio class:
	At September 30, 2014
(In thousands)	Unpaid			Total			Recorded			Recorded			Related
	Principal			Recorded			Investment			Investment			Valuation
	Balance			Investment			No Allowance			With Allowance			Allowance
Residential:
1-4 family	$	159,486		$	144,355		$	24,272		$	120,083		$	11,501
Consumer:
Home equity	60,717			51,503			26,885			24,618			4,165
Commercial:
Commercial non-mortgage	50,359			41,329			17,754			23,575			1,717
Commercial real estate:
Commercial real estate	90,230			88,209			42,743			45,466			3,786
Commercial construction	9,438			8,230			7,517			713			32
Equipment financing	2,258			1,759			1,114			645			29
Totals:
Residential	159,486			144,355			24,272			120,083			11,501
Consumer	60,717			51,503			26,885			24,618			4,165
Commercial	50,359			41,329			17,754			23,575			1,717
Commercial real estate	99,668			96,439			50,260			46,179			3,818
Equipment financing	2,258			1,759			1,114			645			29
Total	$	372,488		$	335,385		$	120,285		$	215,100		$	21,230
	At December 31, 2013
(In thousands)	Unpaid			Total			Recorded			Recorded			Related
	Principal			Recorded			Investment			Investment			Valuation
	Balance			Investment			No Allowance			With Allowance			Allowance
Residential:
1-4 family	$	158,361		$	142,871		$	23,988		$	118,883		$	10,534
Consumer:
Home equity	63,886			52,179			27,323			24,856			4,595
Commercial:
Commercial non-mortgage	59,279			52,199			23,138			29,061			1,878
Commercial real estate:
Commercial real estate	95,013			90,976			42,774			48,202			3,444
Commercial construction	11,725			10,625			10,625			—			—
Equipment financing	249			210			210			—			—
Totals:
Residential	158,361			142,871			23,988			118,883			10,534
Consumer	63,886			52,179			27,323			24,856			4,595
Commercial	59,279			52,199			23,138			29,061			1,878
Commercial real estate	106,738			101,601			53,399			48,202			3,444
Equipment financing	249			210			210			—			—
Total	$	388,513		$	349,060		$	128,058		$	221,002		$	20,451
The following table summarizes the average recorded investment and interest income recognized for impaired loans and leases by portfolio class:
	30-Sep-14			Three months ended September 30, 2014						Nine months ended September 30, 2014							30-Sep-13			Three months ended September 30, 2013					Nine months ended September 30, 2013
(In thousands)	Average			Accrued			Cash Basis Interest Income			Accrued			Cash Basis Interest Income				Average			Accrued			Cash Basis Interest Income		Accrued		Cash Basis Interest Income
	Recorded			Interest						Interest							Recorded			Interest					Interest
	Investment			Income						Income							Investment			Income					Income
Residential:
1-4 family	$	143,613		$	1,144		$	305		$	3,482		$	912			$	145,240		$	1,015		$	520	$	3,098	$	1,476
Consumer:
Home equity	51,841			372			307			1,100			930				53,850			250			413		748		1,301
Commercial:
Commercial non-mortgage	46,764			617			—			1,787			—				65,808			794			—		2,187		—
Commercial real estate:
Commercial real estate	89,593			933			—			2,585			—				116,307			1,109			—		3,675		—
Commercial construction	9,428			75			—			216			—				16,323			161			—		482		—
Equipment financing	985			11			—			17			—				1,136			6			—		19		—
Totals:
Residential	143,613			1,144			305			3,482			912				145,240			1,015			520		3,098		1,476
Consumer	51,841			372			307			1,100			930				53,850			250			413		748		1,301
Commercial	46,764			617			—			1,787			—				65,808			794			—		2,187		—
Commercial real estate	99,021			1,008			—			2,801			—				132,630			1,270			—		4,157		—
Equipment financing	985			11			—			17			—				1,136			6			—		19		—
Total	$	342,224		$	3,152		$	612		$	9,187		$	1,842			$	398,664		$	3,335		$	933	$	10,209	$	2,777
Credit Risk Management. The Company has credit policies and procedures in place designed to maximize loan income within an acceptable level of risk. Management reviews and approves these policies and procedures on a regular basis and reviews reports related to loan production, loan quality, concentrations, delinquencies, non-performing and potential problem loans.
Commercial loans are underwritten after evaluating and understanding the borrower’s ability to operate profitably. Underwriting standards are designed to promote relationships rather than transactional banking. Once it is determined that the borrower’s management possesses sound ethics and solid business acumen, the Company’s management examines current and projected cash flows to determine the ability of the borrower to repay obligations as agreed. Commercial and industrial loans are primarily made based on the identified cash flows of the borrower and secondarily on the underlying collateral provided by the borrower. The cash flows of borrowers, however, may not be as expected and the collateral securing these loans may fluctuate in value. Most commercial and industrial loans are secured by the assets being financed and may incorporate personal guarantees of the principals.
Commercial real estate loans are subject to underwriting standards and processes similar to commercial and industrial loans, in addition to those specific to real estate loans. These loans are viewed primarily as cash flow loans and secondarily as loans secured by real estate. Repayment of these loans is largely dependent on the successful operation of the property securing the loan, the market in which the property is located, and the tenants of the property securing the loan. The properties securing the Company’s commercial real estate portfolio are diverse in terms of type and geographic location, which reduces the Company's exposure to adverse economic events that may affect a particular market. Management monitors and evaluates commercial real estate loans based on collateral, geography, and risk grade criteria. Commercial real estate loans may be adversely affected by conditions in the real estate markets or in the general economy. The Company also utilizes third-party experts to provide insight and guidance about economic conditions and trends affecting its commercial real estate loan portfolio.
Construction loans on commercial properties have unique risk characteristics and are provided to experienced developers/sponsors with strong track records of successful completion and sound financial condition and are underwritten utilizing feasibility studies, independent appraisals, sensitivity analysis of absorption and lease rates, and financial analysis of the developers and property owners. Construction loans are generally based upon estimates of costs and value associated with the complete project. These estimates may be subject to change as the construction project proceeds. Sources of repayment for these types of loans may be pre-committed permanent loans from approved long-term lenders, sales of developed property, or an interim loan commitment from the Company until permanent financing is obtained. These loans are closely monitored by on-site inspections by third-party professionals and the Company's internal staff.
Policies and procedures are in place to manage consumer loan risk and are developed and modified, as needed. Policies and procedures, coupled with relatively small loan amounts, and predominately collateralized structures spread across many individual borrowers, minimize risk. Trend and outlook reports are reviewed by management on a regular basis. Underwriting factors for mortgage and home equity loans include the borrower’s FICO score, the loan amount relative to property value, and the borrower’s debt to income level and are also influenced by regulatory requirements. Additionally, Webster Bank originates both qualified mortgage (QM) and non-QM loans as defined by the Consumer Financial Protection Bureau rules that went into effect on January 10, 2014, with appropriate policies, procedures, and underwriting guidelines that include ability-to-repay standards.
Credit Quality Indicators. To measure credit risk for the commercial, commercial real estate, and equipment financing portfolios, the Company employs a dual grade credit risk grading system for estimating the probability of borrower default and the loss given default. The credit risk grade system assigns a rating to each borrower and to the facility, which together form a Composite Credit Risk Profile (“CCRP”). The credit risk grade system categorizes borrowers by common financial characteristics that measure the credit strength of borrowers and facilities by common structural characteristics. The CCRP has 10 grades, with each grade corresponding to a progressively greater risk of default. Grades 1 through 6 are considered pass ratings, and 7 through 10 are criticized as defined by the regulatory agencies. Risk ratings, assigned to differentiate risk within the portfolio, are reviewed on an ongoing basis and revised to reflect changes in the borrowers’ current financial positions and outlooks, risk profiles, and the related collateral and structural positions. Loan officers review updated financial information on at least an annual basis for all pass rated loans to assess the accuracy of the risk grade. All criticized loans undergo frequent review and enhanced monitoring of the underlying borrower.
A “Special Mention” (7) credit has the potential weakness that, if left uncorrected, may result in deterioration of the repayment prospects for the asset. “Substandard” (8) assets have a well defined weakness that jeopardizes the full repayment of the debt. An asset rated “Doubtful” (9) has all of the same weaknesses as a substandard credit with the added characteristic that the weakness makes collection or liquidation in full, given current facts, conditions, and values, improbable. Assets classified as “Loss” (10) in accordance with regulatory guidelines are considered uncollectible and charged off.
The recorded investment in commercial and commercial real estate loans and equipment financing leases segregated by risk rating exposure is as follows:
	Commercial								Commercial Real Estate								Equipment Financing
(In thousands)	At September 30,				At December 31,				At September 30,				At December 31,				At September 30,				At December 31,
	2014				2013				2014				2013				2014				2013
(1) - (6) Pass	$	3,474,698			$	3,091,154			$	3,191,834			$	2,947,116			$	468,407			$	437,033
(7) Special Mention	63,830				87,451				61,354				20,901				2,080				7,979
(8) Substandard	105,008				114,199				108,762				97,822				19,663				15,438
(9) Doubtful	199				440				508				585				—				—
(10) Loss	—				—				—				—				—				—
Total	$	3,643,735			$	3,293,244			$	3,362,458			$	3,066,424			$	490,150			$	460,450
For residential and consumer loans, the Company considers factors such as updated FICO scores, employment status, home prices, loan to value, geography, loans discharged in bankruptcy, and the status of first lien position loans on second lien position loans as credit quality indicators. On an ongoing basis for portfolio monitoring purposes, the Company estimates the current value of property secured as collateral for both home equity and residential first mortgage lending products. The estimate is based on home price indices compiled by the S&P/Case-Shiller Home Price Indices. The Case-Shiller data indicates trends for Metropolitan Statistical Areas. The trend data is applied to the loan portfolios taking into account the age of the most recent valuation and geographic area.
Troubled Debt Restructurings. The following table summarizes information for TDRs:
(Dollars in thousands)	At September 30,				At December 31,
	2014				2013
Recorded investment of TDRs:
Accrual status (1)	$	236,128			$	238,926
Non-accrual status (1)	87,003				102,972
Total recorded investment of TDRs	$	323,131			$	341,898
Accruing TDRs performing under modified terms more than one year	68.4		%		58.2		%
Specific reserves for TDRs included in the balance of allowance for loan and lease losses	$	20,745			$	20,360
Additional funds committed to borrowers in TDR status	495				1,262
-1	A total of $17.6 million in residential and consumer loans was reclassified from non-accrual to accrual status in the nine months ended September 30, 2014 as a result of updated regulatory guidance issued in the first quarter of 2014.
For the three and nine months ended September 30, 2014 and 2013, Webster charged off $2.1 million and $10.3 million and $3.2 million and $17.3 million, respectively, for the portion of TDRs deemed to be uncollectible.
TDRs may be modified by means of extended maturity, below market adjusted interest rates, a combination of rate and maturity, or other means, including covenant modifications, forbearance, loans discharged under Chapter 7 bankruptcy, or other concessions.
The following table provides information on how loans and leases were modified as TDRs:
	Three months ended September 30,											Nine months ended September 30,
	2014					2013						2014					2013
Type of concession	Number of		Post-			Number of		Post-				Number of		Post-			Number of		Post-
	Loans and		Modification			Loans and		Modification				Loans and		Modification			Loans and		Modification
	Leases		Recorded			Leases		Recorded				Leases		Recorded			Leases		Recorded
(Dollars in thousands)			Investment(1)					Investment(1)						Investment(1)					Investment(1)
Residential:
Extended Maturity	10		$	1,383		10		$	1,898			24		$	3,191		22		$	4,418
Adjusted Interest rates	1		103			1		654				3		448			6		1,888
Combination Rate and Maturity	2		275			8		1,142				16		3,522			38		7,213
Other	32		7,600			5		1,177				47		10,433			30		5,611
Consumer:
Extended Maturity	4		143			10		307				18		911			20		961
Adjusted Interest rates	—		—			—		—				1		51			4		154
Combination Rate and Maturity	1		110			3		164				6		412			13		1,381
Other	34		1,750			28		811				73		3,717			78		3,197
Commercial:
Extended Maturity	—		—			—		—				4		356			2		7,520
Adjusted Interest rates	—		—			—		—				1		25			—		—
Combination Rate and Maturity	5		342			12		353				18		974			19		982
Other	2		101			2		4,568				5		6,647			3		4,607
Commercial real estate:
Extended Maturity	—		—			—		—				—		—			3		227
Combination Rate and Maturity	—		—			2		340				—		—			4		12,015
Equipment Financing
Extended Maturity	1		492			—		—				1		492			—		—
TOTAL TDRs	92		$	12,299		81		$	11,414			217		$	31,179		242		$	50,174
(1) Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs as a result of the restructurings was not significant.
The Company’s loan and lease portfolio at September 30, 2014 included loans with an A Note/B Note structure. The loans were restructured into A Note/B Note structures as a result of evaluating the cash flow of the borrowers to support repayment. Webster immediately charged off the balance of B Notes. The restructuring agreements specify a market interest rate equal to that which would be provided to a borrower with similar credit at the time of restructuring.
The following table provides information on loans and leases modified as TDRs within the previous 12 months and for which there was a payment default during the periods presented:
	Three months ended September 30,										Nine months ended September 30,
	2014					2013					2014					2013
(Dollars in thousands)	Number of	Recorded				Number of	Recorded				Number of	Recorded				Number of	Recorded
	Loans and	Investment				Loans and	Investment				Loans and	Investment				Loans and	Investment
	Leases					Leases					Leases					Leases
Residential:
1-4 family	3	$	196			8	$	1,116			3	$	196			12	$	1,814
Consumer:
Home equity	2	22				3	53				4	48				7	343
Commercial real estate:
Commercial real estate	—	—				1	500				—	—				1	500
Total	5	$	218			12	$	1,669			7	$	244			20	$	2,657
The recorded investment in commercial, commercial real estate, and equipment financing TDRs segregated by risk rating exposure is as follows:
(In thousands)	At September 30,				At December 31,
	2014				2013
(1) - (6) Pass	$	37,861			$	55,973
(7) Special Mention	18,268				—
(8) Substandard	70,601				90,461
(9) Doubtful	346				414
(10) Loss	—				—
Total	$	127,076			$	146,848

Transfers_of_Financial_Assets_

Transfers of Financial Assets and Mortgage Servicing Assets	9 Months Ended
	Sep. 30, 2014
Transfers and Servicing [Abstract]	'
Transfers of Financial Assets and Mortgage Servicing Assets	'
	Transfers of Financial Assets and Mortgage Servicing Assets
	Transfers of Financial Assets
	The Company sells financial assets in the normal course of business, the majority of which are residential mortgage loans primarily to government-sponsored enterprises through established programs, commercial loans through participation agreements, and other individual or portfolio loans and securities. In accordance with the accounting guidance for asset transfers, the Company considers any ongoing involvement with transferred assets in determining whether the assets can be derecognized from the balance sheet. For loans sold under participation agreements, the Company also considers the terms of the loan participation agreement and whether they meet the definition of a participating interest, and thus, qualify for derecognition.
	With the exception of servicing rights and certain performance-based guarantees, the Company’s continuing involvement with financial assets sold is minimal and limited to customary market representations and warranties covering certain characteristics of the mortgage loans sold and the Company's origination process, which the Company makes in the sale agreements. The Company may be required to repurchase a loan in the event of certain breaches of these representations and warranties or in the event of default of the borrower within 90 days of sale. The gain or loss on loans sold depends on the previous carrying amount of the transferred financial assets, the consideration received, and any liabilities incurred in exchange for the transferred assets, and is included as mortgage banking activities in the accompanying Condensed Consolidated Statements of Income.
	A reserve provides for estimated losses associated with the repurchase of loans sold in connection with the Company’s mortgage banking operations. The reserve for loan repurchases reflects management’s monthly evaluation of counterparty, the vintage of the loans sold, the amount of open repurchase requests, specific loss estimates for each open request, current level of loan losses in similar vintages held in the residential loan portfolio, and estimated recoveries on the underlying collateral. This reserve also reflects management’s expectation of losses from repurchase requests for which the Company has not yet been notified. While management uses its best judgment and information available, the adequacy of the reserve is dependent upon factors outside the Company's control including the performance of loans sold and the quality of the servicing provided by the acquirer. The provision recorded at the time of loan sale is netted from the gain or loss recorded in mortgage banking activities, while any incremental provision, post loan sale, is recorded in other non-interest expense in the accompanying Condensed Consolidated Statements of Income.
	The following table provides a summary of activity in the reserve for loan repurchases:
		Three months ended September 30,					Nine months ended September 30,
	(In thousands)	2014		2013			2014			2013
	Beginning balance	$	1,575	$	2,648		$	2,254		$	2,617
	Provision (benefit)	132		447			(391		)	1,462
	Loss on repurchased loans and settlements	—		(586		)	(156		)	(1,570		)
	Ending balance	$	1,707	$	2,509		$	1,707		$	2,509
	The following table provides detail of activity related to loan sales:
		Three months ended September 30,					Nine months ended September 30,
	(In thousands)	2014		2013			2014			2013
	Residential mortgage loans:
	Proceeds from the sale of loans held for sale	$	85,311	$	199,903		$	207,530		$	657,541
	Net gain on sale included as mortgage banking activities	1,805		665			3,093			13,900
	Loans sold with servicing rights retained	78,848		192,283			193,781			622,550
	Commercial loans:
	Proceeds from the sale of loans held for sale	—		—			—			12,685
	Net loss on sale included as mortgage banking activities	—		—			—			(316		)
	Mortgage Servicing Assets
	The Company has retained servicing rights on consumer loans totaling $2.4 billion at both September 30, 2014 and December 31, 2013, resulting in mortgage servicing assets of $19.7 million at September 30, 2014 and $21.0 million at December 31, 2013, which are carried at the lower of cost or fair value. See Note 14 - Fair Value Measurements for a further discussion on the fair value of mortgage servicing assets.
	Loan servicing fees, net of mortgage servicing rights amortization, were $0.7 million and $1.4 million and $0.4 million and $2.5 million for the three and nine months ended September 30, 2014 and 2013, respectively, and are included as a component of loan related fees in the accompanying Condensed Consolidated Statements of Income.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Other Intangible Assets	'
	Goodwill and Other Intangible Assets
	The following table presents the carrying value for goodwill allocated to the segments:
	(In thousands)	At September 30, 2014			At December 31, 2013
	Segment:
	Community Banking	$	516,560		$	516,560
	Other	13,327			13,327
	Goodwill	$	529,887		$	529,887
	The gross carrying amount and accumulated amortization of other intangible assets (core deposits) allocated to the business segments are as follows:
		At September 30, 2014							At December 31, 2013
	(In thousands)	Gross Carrying		Accumulated			Net Carrying		Gross Carrying		Accumulated			Net Carrying
		Amount		Amortization			Amount		Amount		Amortization			Amount
	Community Banking	$	49,420	$	(46,338	)	$	3,082	$	49,420	$	(44,069	)	$	5,351
	Amortization of intangible assets for the three and nine months ended September 30, 2014 and 2013, totaled $0.4 million and $2.3 million and $1.2 million and $3.7 million, respectively. Future estimated annual amortization expense is summarized below:
	(In thousands)
	Years ending December 31:
	Remainder of 2014	$	415
	2015	1,524
	2016	1,143

Deposits

Deposits	9 Months Ended
	Sep. 30, 2014
Banking and Thrift [Abstract]	'
Deposits	'
	Deposits
	A summary of deposits by type follows:
	(In thousands)	At September 30,		At December 31,
		2014		2013
	Non-interest-bearing:
	Demand	$	3,256,741	$	3,128,152
	Interest-bearing:
	Checking	2,105,481		1,934,291
	Health savings accounts	1,765,671		1,533,310
	Money market	2,239,106		2,167,593
	Savings	3,877,673		3,863,930
	Time deposits	2,302,246		2,227,144
	Total interest-bearing	12,290,177		11,726,268
	Total deposits	$	15,546,918	$	14,854,420
	Demand deposit overdrafts reclassified as loan balances	$	1,791	$	1,455
	At September 30, 2014, the scheduled maturities of time deposits are as follows:
	(In thousands)	Years ending December 31:
	2014	$	357,663
	2015	1,041,544
	2016	305,677
	2017	120,685
	2018	149,111
	Thereafter	327,566
	Time deposits	$	2,302,246
	Included in the balances above are time deposits and interest-bearing checking accounts obtained through brokers, totaling $350.5 million and $205.9 million at September 30, 2014 and December 31, 2013, respectively.

Securities_Sold_Under_Agreemen

Securities Sold Under Agreements to Repurchase and Other Borrowings	9 Months Ended
	Sep. 30, 2014
Securities Sold Under Agreements to Repurchase and Other Short-term Borrowings [Abstract]	'
Securities Sold Under Agreements to Repurchase and Other Borrowings	'
	Securities Sold Under Agreements to Repurchase and Other Borrowings
	The following table summarizes securities sold under agreements to repurchase and other borrowings:
	(In thousands)	At September 30,		At December 31,
		2014		2013
	Securities sold under agreements to repurchase:
	Original maturity of one year or less	$	398,975	$	359,662
	Original maturity of greater than one year, non-callable	550,000		550,000
	Callable at the option of the counterparty (1)	—		100,000
		948,975		1,009,662
	Other borrowings:
	Federal funds purchased	288,000		322,000
	Securities sold under agreements to repurchase and other borrowings	$	1,236,975	$	1,331,662
	-1	There were $100 million of securities sold under agreements to repurchase that had callable options for June 23, 2014 and were classified as callable at the option of the counterparty at December 31, 2013. The callable options were not exercised as of the call date and were reclassified as original maturity of greater than one year, non-callable during the quarter ended September 30, 2014.
	Repurchase agreements are used as a source of borrowed funds and are collateralized by U.S. Government agency mortgage-backed securities which are delivered to broker/dealers. Repurchase agreements with counterparties are limited to primary dealers in government securities or commercial and municipal customers through Webster’s Treasury Sales desk. Dealer counterparties have the right to pledge, transfer, or hypothecate purchased securities during the term of the transaction. The Company has right of offset with respect to all repurchase agreement assets and liabilities. At September 30, 2014, the Company has a gross repurchase agreement liability of $0.9 billion.

Federal_Home_Loan_Bank_Advance

Federal Home Loan Bank Advances	9 Months Ended
	Sep. 30, 2014
Federal Home Loan Banks [Abstract]	'
Federal Home Loan Bank Advances	'
	Federal Home Loan Bank Advances
	The following table summarizes Federal Home Loan Bank advances:
		At September 30, 2014				At December 31, 2013
	(Dollars in thousands)	Total		Weighted-		Total		Weighted-
		Outstanding		Average Contractual Coupon Rate		Outstanding		Average Contractual Coupon Rate
	FHLB advances maturing:
	Within 1 year	$	1,775,000	0.2	%	$	1,550,000	0.25	%
	After 1 but within 2 years	145,934		1.8		—		—
	After 2 but within 3 years	—		—		145,934		1.8
	After 3 but within 4 years	100,500		1.49		500		5.66
	After 4 but within 5 years	108,731		1.33		200,000		1.36
	After 5 years	159,996		1.25		155,926		1.25
		2,290,161		0.48	%	2,052,360		0.54	%
	Unamortized premiums	43				61
	Federal Home Loan Bank advances	$	2,290,204			$	2,052,421
	At September 30, 2014, Webster Bank had pledged loans with an aggregate carrying value of $5.0 billion as collateral for borrowings and had additional borrowing capacity from the FHLB of approximately $1.0 billion, as well as an unused line of credit of approximately $5.0 million. At December 31, 2013, Webster Bank had pledged loans with an aggregate carrying value of $4.8 billion as collateral for borrowings and had additional borrowing capacity from the FHLB of approximately $1.0 billion, as well as an unused line of credit of approximately $5.0 million. At September 30, 2014 and December 31, 2013, Webster Bank was in compliance with FHLB collateral requirements.

LongTerm_Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Long-Term Debt	'
	Long-Term Debt
	The following table summarizes long-term debt:
	(Dollars in thousands)		At September 30,			At December 31,
			2014			2013
	4.38%	senior fixed-rate notes due 2024 (1)	$	150,000		$	—
	5.13%	senior fixed-rate notes due 2014	—			150,000
	Junior subordinated debt Webster Statutory Trust I floating-rate notes due 2033 (2)		77,320			77,320
	Total notes and subordinated debt		227,320			227,320
	Unamortized discount, net (3)		(1,112		)	(21		)
	Hedge accounting adjustments (3)		—			1,066
	Long-term debt		$	226,208		$	228,365
	-1	On February 11, 2014, Webster completed an underwritten public offering of $150.0 million aggregate principal amount of 4.375% senior notes maturing February 15, 2024. Webster received net proceeds of $148.0 million from the public offering
	-2	The interest rate on Webster Statutory Trust I floating-rate notes, which varies quarterly based on 3-month LIBOR plus 2.95%, was 3.185% at September 30, 2014 and 3.194% at December 31, 2013
	-3	Related to senior fixed-rate notes due 2024 at September 30, 2014 and senior fixed-rate notes due 2014 at December 31, 2013

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Accumulated Other Comprehensive Loss	'
	Accumulated Other Comprehensive Loss
	The following tables summarize the changes in accumulated other comprehensive loss by component:
		Three months ended September 30, 2014
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	21,256		$	(24,450	)	$	(26,801	)	$	(29,995	)
	Other comprehensive (loss) income before reclassifications	(8,133		)	493			437			(7,203		)
	Amounts reclassified from accumulated other comprehensive (loss) income	36			1,180			63			1,279
	Net current-period other comprehensive (loss) income, net of tax	(8,097		)	1,673			500			(5,924		)
	Ending balance	$	13,159		$	(22,777	)	$	(26,301	)	$	(35,919	)
		Three months ended September 30, 2013
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	2,729		$	(22,872	)	$	(44,996	)	$	(65,139	)
	Other comprehensive income (loss) before reclassifications	5,330			(1,413		)	528			4,445
	Amounts reclassified from accumulated other comprehensive income (loss)	(173		)	1,400			526			1,753
	Net current-period other comprehensive income (loss), net of tax	5,157			(13		)	1,054			6,198
	Ending balance	$	7,886		$	(22,885	)	$	(43,942	)	$	(58,941	)
		Nine months ended September 30, 2014
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	(2,617	)	$	(18,206	)	$	(27,726	)	$	(48,549	)
	Other comprehensive income (loss) before reclassifications	18,420			(8,534		)	1,372			11,258
	Amounts reclassified from accumulated other comprehensive income (loss)	(2,644		)	3,963			53			1,372
	Net current-period other comprehensive income (loss), net of tax	15,776			(4,571		)	1,425			12,630
	Ending balance	$	13,159		$	(22,777	)	$	(26,301	)	$	(35,919	)
		Nine months ended September 30, 2013
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	42,741		$	(27,902	)	$	(47,105	)	$	(32,266	)
	Other comprehensive (loss) income before reclassifications	(34,400		)	467			1,584			(32,349		)
	Amounts reclassified from accumulated other comprehensive (loss) income	(455		)	4,550			1,579			5,674
	Net current-period other comprehensive (loss) income, net of tax	(34,855		)	5,017			3,163			(26,675		)
	Ending balance	$	7,886		$	(22,885	)	$	(43,942	)	$	(58,941	)
	The following tables summarize the reclassifications out of accumulated other comprehensive loss:
		Three months ended September 30,
		2014			2013
	Accumulated Other Comprehensive Loss Components	Amount Reclassified From Accumulated Other Comprehensive Loss			Amount Reclassified From Accumulated Other Comprehensive Loss			Associated Line Item in the Condensed Consolidated Statements Of Income
	(In thousands)
	Available-for-sale and transferred securities:
	Unrealized gains (losses) on investment securities	$	42		$	269		Net gain on sale of investment securities
	Unrealized gains (losses) on investment securities	(85		)	—			Impairment loss recognized in earnings
	Tax benefit (expense)	7			(96		)	Income tax expense
	Net of tax	$	(36	)	$	173
	Derivative instruments:
	Cash flow hedges	$	(1,853	)	$	(2,182	)	Total interest expense
	Tax benefit	673			782			Income tax expense
	Net of tax	$	(1,180	)	$	(1,400	)
	Defined benefit pension and postretirement benefit plans:
	Amortization of net loss	$	(80	)	$	(803	)	Compensation and benefits
	Prior service costs	(19		)	(18		)	Compensation and benefits
	Tax benefit	36			295			Income tax expense
	Net of tax	$	(63	)	$	(526	)
		Nine months ended September 30,
		2014			2013
	Accumulated Other Comprehensive Loss Components	Amount Reclassified From Accumulated Other Comprehensive Loss			Amount Reclassified From Accumulated Other Comprehensive Loss			Associated Line Item in the Condensed Consolidated Statements Of Income
	(In thousands)
	Available-for-sale and transferred securities:
	Unrealized gains (losses) on investment securities	$	4,378		$	708		Net gain on sale of investment securities
	Unrealized gains (losses) on investment securities	(246		)	—			Impairment loss recognized in earnings
	Tax expense	(1,488		)	(253		)	Income tax expense
	Net of tax	$	2,644		$	455
	Derivative instruments:
	Cash flow hedges	$	(6,189	)	$	(7,090	)	Total interest expense
	Tax benefit	2,226			2,540			Income tax expense
	Net of tax	$	(3,963	)	$	(4,550	)
	Defined benefit pension and postretirement benefit plans:
Amortization of net loss	$	(28	)	$	(2,407	)	Compensation and benefits
Prior service costs	(55		)	(54		)	Compensation and benefits
Tax benefit	30			882			Income tax expense
Net of tax	$	(53	)	$	(1,579	)

Regulatory_Matters

Regulatory Matters	9 Months Ended
	Sep. 30, 2014
Regulatory Matters Disclosure [Abstract]	'
Regulatory Matters	'
	Regulatory Matters
	Regulatory Capital Requirements. Banks and bank holding companies are subject to various regulatory capital requirements administered by federal banking agencies. Capital adequacy guidelines and, additionally for banks, prompt corrective action regulations involve quantitative measures of assets, liabilities, and certain off-balance sheet items calculated under regulatory accounting practices. These quantitative measures, to ensure capital adequacy, require minimum amounts and ratios.
	As defined in the regulations, the Total risk-based and Tier 1 capital ratios are calculated by dividing the respective capital amounts by risk-weighted assets. Risk-weighted assets are calculated based on regulatory requirements and include total assets, excluding goodwill and other intangible assets, allocated by risk-weight category, and certain off-balance sheet items, primarily loan commitments. As defined in the regulations, the Tier 1 leverage capital ratio is calculated by dividing Tier 1 capital by adjusted quarterly average total assets. Capital amounts and classifications are also subject to qualitative judgments by regulators about components, risk-weighting, and other factors.
	The following table provides information on the capital ratios for Webster Financial Corporation and Webster Bank, N.A.:
		Capital				Capital Requirements
		Actual				Minimum				Well Capitalized
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	At September 30, 2014
	Webster Financial Corporation
	Total risk-based capital	$	2,060,208	14.2	%	$	1,163,206	8	%	$	1,454,008	10	%
	Tier 1 capital	1,898,704		13.1		581,603		4		872,405		6
	Tier 1 leverage capital	1,898,704		9		840,727		4		1,050,909		5
	Webster Bank, N.A.
	Total risk-based capital	$	1,901,130	13.1	%	$	1,161,080	8	%	$	1,451,350	10	%
	Tier 1 capital	1,739,626		12		580,540		4		870,810		6
	Tier 1 leverage capital	1,739,626		8.3		839,728		4		1,049,660		5
	At December 31, 2013
	Webster Financial Corporation
	Total risk-based capital	$	1,965,171	14.2	%	$	1,106,203	8	%	$	1,382,754	10	%
	Tier 1 capital	1,807,642		13.1		553,101		4		829,652		6
	Tier 1 leverage capital	1,807,642		9		801,535		4		1,001,919		5
	Webster Bank, N.A.
	Total risk-based capital	$	1,815,423	13.2	%	$	1,104,200	8	%	$	1,380,250	10	%
	Tier 1 capital	1,658,466		12		552,100		4		828,150		6
	Tier 1 leverage capital	1,658,466		8.3		800,063		4		1,000,079		5
	Webster is subject to regulatory capital requirements administered by the Federal Reserve, while Webster Bank is subject to regulatory capital requirements administered by the Office of the Comptroller of the Currency ("OCC"). Regulatory authorities can initiate certain mandatory actions if Webster or Webster Bank fail to meet minimum capital requirements, which could have a direct material effect on the Company’s financial statements.
	Dividend Restrictions. In the ordinary course of business, Webster is dependent upon dividends from Webster Bank to provide funds for its cash requirements, including payments of dividends to shareholders. Banking regulations may limit the amount of dividends that may be paid. Approval by regulatory authorities is required if the effect of dividends declared would cause the regulatory capital of Webster Bank to fall below specified minimum levels, or if dividends declared exceed the net income for that year combined with the undistributed net income for the preceding two years. In addition, the OCC has discretion to prohibit any otherwise permitted capital distribution on general safety and soundness grounds. Dividends paid by Webster Bank to Webster totaled $80.0 million and $70.0 million during the nine months ended September 30, 2014 and 2013, respectively.
	Trust Preferred Securities. The Company owns the common stock of a trust which has issued trust preferred securities. The trust is a VIE of which the Company is not the primary beneficiary and, therefore, is not consolidated. At September 30, 2014 and December 31, 2013, $75.0 million of trust preferred securities have been included in the Tier 1 capital of Webster for regulatory reporting purposes pursuant to the Federal Reserve's capital adequacy guidelines. Certain provisions of the Basel III capital framework require the Company to phase out trust preferred securities from Tier 1 capital beginning January 1, 2015. Excluding trust preferred securities from the Tier 1 capital will not affect Webster's ability to meet all capital adequacy requirements to which it is subject.

Earnings_Per_Common_Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Common Share	'
	Earnings Per Common Share
	The calculation of basic and diluted earnings per common share follows:
		Three months ended September 30,				Nine months ended September 30,
	(In thousands, except per share data)	2014		2013		2014		2013
	Earnings for basic and diluted earnings per common share:
	Net income available to common shareholders	$	47,819	$	44,666	$	140,820	$	127,631
	Less: Earnings allocated to participating securities	171		162		530		497
	Net income allocated to common shareholders	$	47,648	$	44,504	$	140,290	$	127,134
	Shares:
	Weighted-average common shares outstanding - basic	89,888		89,759		89,850		88,318
	Effect of dilutive securities:
	Stock options and restricted stock	464		451		471		406
	Warrants - Series A1 and A2	—		—		—		1,300
	Warrants - other	262		213		270		169
	Weighted-average common shares outstanding - diluted	90,614		90,423		90,591		90,193
	Earnings per common share:
	Basic	$	0.53	$	0.5	$	1.56	$	1.44
	Diluted	0.53		0.49		1.55		1.41
	Stock Options
	Options to purchase 0.8 million shares for both the three and nine months ended September 30, 2014, respectively, and 1.1 million shares and 1.2 million for the three and nine months ended September 30, 2013, respectively, were excluded from the calculation of diluted earnings per share because the options’ exercise prices were greater than the average market price of Webster's common stock for the respective periods presented.
	Restricted Stock
	Non-participating restricted stock awards of 157 thousand shares and 178 thousand shares for the three and nine months ended September 30, 2014, respectively, and 189 thousand shares and 224 thousand shares for the three and nine months ended September 30, 2013, respectively, whose issuance is contingent upon the satisfaction of certain performance conditions, were deemed to be anti-dilutive and, therefore, are excluded from the calculation of diluted earnings per share for the respective periods presented.
	Warrants
	Series A1 and A2: The Series A1 and A2 warrants issued in connection with the Warburg investment were exchanged in a cashless exercise on March 22, 2013. The weighted-average dilutive effect of these warrants prior to the exchange is included in the calculation of diluted earnings per share for the nine months ended September 30, 2013 because the exercise price of the warrants was less than the average market price of Webster's common stock for that period.
	Other: Warrants initially issued to the U.S. Treasury and sold in a secondary public offering on June 8, 2011 represent 0.7 million potential issuable shares of common stock at both September 30, 2014 and 2013. The weighted-average dilutive effect of these warrants is included in the calculation of diluted earnings per share for the three and nine months ended September 30, 2014 and 2013 because the exercise price of the warrants was less than the average market price of Webster’s common stock for the respective periods presented.
	Series A Preferred Stock
	The Series A Preferred Stock represents potential issuable common stock at September 30, 2014 and 2013. The weighted-average effect of 1.1 million shares of common stock associated with the Series A Preferred Stock was deemed to be anti-dilutive and, therefore, is excluded from the calculation of diluted earnings per share for the three and nine months ended September 30, 2014 and 2013.

Derivative_Financial_Instrumen

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Financial Instruments	'
	Derivative Financial Instruments
	Risk Management Objective of Using Derivatives
	Webster manages economic risks, including interest rate, liquidity, and credit risk, primarily by managing the amount, sources, and duration of its debt funding and the use of derivative financial instruments. Specifically, Webster enters into derivative financial instruments to manage exposure that arises from business activities, that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. Cash flow or fair value hedge designation, for accounting, depends on the specific risk being hedged. Webster uses fair value hedges to mitigate changes in fair values due to fixed rates or prices, while changes in cash flows due to variable rates or prices may be reduced or eliminated by cash flow hedges.
	Cash Flow Hedges of Interest Rate Risk
	Webster’s primary objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements. To accomplish these objectives, Webster uses interest rate swaps and caps as part of its interest rate risk management strategy. Interest rate swaps and caps designated as cash flow hedges are designed to manage the risk associated with a forecasted event or an uncertain variable rate cash flow. The change in fair value of interest rate swaps and caps is recorded in accumulated other comprehensive income ("AOCI") during the term of the cash flow hedge.
	Webster uses forward-settle interest rate swaps to protect the Company against adverse fluctuations in interest rates by reducing its exposure to variability in cash flows relating to interest payments on forecasted debt issuances. The current forward-settle interest rate swaps are structured as pay fixed-receive 1-month LIBOR. Forward-settle swaps are typically terminated and cash settled to coincide with a debt issuance. Upon the termination of a swap at the time of debt issuance, the gain or loss that has been recorded in AOCI is amortized into interest expense over the life of the debt.
	The table below presents information for Webster's forward-settle interest rate swaps outstanding at September 30, 2014:
	(Dollars in thousands)
	Number of Instruments	Total Notional Amount			Trade Date	Effective Date	Maturity Date	Debt Issuance Expected
	1	$	25,000		Sep-13	Jun-14	Jun-19	At or before March 2015
	4	$	100,000		October 2013, November 2013	October 2014, November 2014	October 2019, November 2019	At or before May 2015
	2	$	50,000		Jan-14	Jan-15	Jan-20	October 2014 - July 2015
	2	$	50,000		April 2014, May 2014	Jun-15	Jun-20	March 2015 - December 2015
	Webster uses interest rate swaps and caps to protect the Company from exposure to variability in cash flows relating to interest payments on floating-rate funding instruments. The swaps and caps are structured to offset fluctuations in interest rates on floating-rate debt during the life of the funding instrument.
	The table below presents information for Webster's interest rate swaps and caps outstanding at September 30, 2014:
	(Dollars in thousands)
	Number of Instruments	Total Notional Amount			Instrument Type	Trade Date	Index Rate	Hedged Debt	Maturity Date
	6	$	150,000		Cap	April 2013, January 2014, February 2014, April 2014	3.0% strike	$150 million 3-month LIBOR indexed floating-rate FHLB advance	Dec-21
	4	$	100,000		Swap	June 2014, July 2014	1-month LIBOR	$100 million 28 day rolling FHLB advance for a 5 year term	July 2019, August 2019, September 2019
	The table below presents the notional amount and fair value for Webster’s interest rate derivatives designated as cash flow hedges as well as their classification in the accompanying Condensed Consolidated Balance Sheets:
			At September 30, 2014								At December 31, 2013
	(Dollars in thousands)	Balance Sheet	# of	Notional			Fair				# of	Notional			Fair
		Classification	Instruments	Amount			Value				Instruments	Amount			Value
	Forward-settle interest rate swap	Other assets	—	$	—		$	—			8	$	200,000		$	3,027
	Forward-settle interest rate swap	Other liabilities	9	225,000			(2,812		)		5	125,000			(622		)
	Interest rate swap	Other assets	4	100,000			263				—	—			—
	Interest rate cap	Other assets	6	150,000			6,094				2	50,000			3,554
	AOCI related to cash flow hedges
	The changes in fair value of derivatives designated as cash flow hedges are recorded in AOCI. These amounts are reclassified to interest expense as interest payments are made on the Company's variable-rate debt. An unamortized interest rate cap premium balance of $8.0 million will be reclassified to interest expense over the term of the cap transactions according to a predetermined cap value schedule. Over the next twelve months, the Company estimates that $4.6 million will be reclassified from AOCI as an increase to interest expense.
	Webster records swap gains and losses related to forward-settle terminations in AOCI with the amortization impacting earnings over the respective term of the hedged debt instruments. There was no hedge ineffectiveness for the three months ended September 30, 2014, while a loss of $107 thousand was recognized for hedge ineffectiveness for the nine months ended September 30, 2014. There was no hedge ineffectiveness for the three and nine months ended September 30, 2013. At September 30, 2014, the remaining unamortized loss on the termination of cash flow hedges is $30.9 million. Over the next twelve months, the Company estimates that $7.5 million will be reclassified from AOCI as an increase to interest expense.
	The increase/(reduction) to interest expense on borrowings related to cash flow hedges is presented below:
		Three months ended September 30,
		2014							2013
	(In thousands)	Interest			Amount Reclassified From AOCI				Interest			Amount Reclassified From AOCI
		Expense							Expense
	Interest rate swaps on FHLB advances	$	188		$	1,355			$	—		$	1,353
	Interest rate swaps on senior fixed-rate notes	—			76				—			—
	Interest rate swaps on junior subordinated debt	—			—				—			—
	Interest rate swaps on repurchase agreements	—			361				—			829
	Interest rate swaps on brokered certificates of deposit	—			61				—			—
	Net increase to interest expense on borrowings	$	188		$	1,853			$	—		$	2,182
		Nine months ended September 30,
		2014							2013
	(In thousands)	Interest			Amount Reclassified From AOCI				Interest			Amount Reclassified From AOCI
		Expense							Expense
	Interest rate swaps on FHLB advances	$	188		$	4,060			$	498		$	4,604
	Interest rate swaps on senior fixed-rate notes	—			191				—			—
	Interest rate swaps on junior subordinated debt	—			—				—			(3		)
	Interest rate swaps on repurchase agreements	—			1,864				—			2,489
	Interest rate swaps on brokered certificates of deposit	—			74				—			—
	Net increase to interest expense on borrowings	$	188		$	6,189			$	498		$	7,090
	Fair Value Hedges of Interest Rate Risk
	Webster is exposed to changes in the fair value of certain of its fixed-rate obligations due to changes in benchmark interest rates. Webster, on occasion, uses interest rate swaps to manage its exposure to changes in fair value on these obligations attributable to changes in the benchmark interest rates. Interest rate swaps designated as fair value hedges involve the receipt of fixed-rate amounts from a counterparty in exchange for Webster making variable-rate payments over the life of the agreements without the exchange of the underlying notional amount. Webster did not have any derivative financial instruments designated as fair value hedges as of September 30, 2014 and December 31, 2013.
	For a qualifying derivative designated as a fair value hedge, the gain or loss on the derivative, as well as the offsetting gain or loss on the hedged item attributable to the hedged risk, is recognized in interest expense. Webster includes the gain or loss from the period end mark-to-market (“MTM”) adjustments on the hedged items in the same line item as the offsetting gain or loss on the related derivatives. The impact of derivative net settlements, hedge ineffectiveness, basis amortization adjustments, and amortization of deferred hedge terminations are also recognized in interest expense.
	The reduction to interest expense on borrowings related to fair value hedges is presented below:
		Three months ended September 30,								Nine months ended September 30,
	(In thousands)	2014				2013				2014				2013
	Interest rate swaps on senior fixed-rate notes	$	—			$	(799	)		$	(1,066	)		$	(2,398	)
	Interest rate swaps on junior subordinated debt	—				—				—				(207		)
	Net reduction to interest expense on borrowings	$	—			$	(799	)		$	(1,066	)		$	(2,605	)
	Non-Hedge Accounting Derivatives / Non-designated Hedges
	Webster has derivatives that do not meet hedge accounting requirements and are accounted for as free-standing derivatives with changes in fair value recorded in non interest income. The Company’s risk management strategy includes the use of derivatives to modify the repricing risk of assets and liabilities. As part of this strategy, the Company uses futures contracts to hedge certain loans. Other derivative instruments include interest rate swap and cap contracts sold to commercial and other customers who wish to modify interest rate sensitivity. These contracts are offset with dealer counterparty transactions structured with matching terms. As a result, there is minimal impact on earnings.
	Webster had the following derivative positions that were not designated for hedge accounting:
		At September 30, 2014
							Fair Value
(Dollars in thousands)	Balance Sheet	# of		Notional			Gain			Loss			Net
	Classification	Instruments		Amount
Webster with customer position:
Commercial loan interest rate derivatives	Other assets	196		$	1,245,748		$	35,207		$	—		$	35,207
Commercial loan interest rate derivatives	Other liabilities	73		685,273			—			(5,534		)	(5,534		)
Total customer position		269		$	1,931,021		$	35,207		$	(5,534	)	$	29,673
Webster with counterparty position:
Commercial loan interest rate derivatives	Other assets	84		$	605,806		$	4,019		$	(2,625	)	$	1,394
Commercial loan interest rate derivatives	Other liabilities	179		1,325,151			5,828			(21,682		)	(15,854		)
Futures contracts	Other liabilities	10		8,000,000			8			(450		)	(442		)
Total counterparty position		273		$	9,930,957		$	9,855		$	(24,757	)	$	(14,902	)
		At December 31, 2013
							Fair Value
(Dollars in thousands)	Balance Sheet	# of		Notional			Gain			Loss			Net
	Classification	Instruments		Amount
Webster with customer position:
Commercial loan interest rate derivatives	Other assets	159		$	915,272		$	29,004		$	—		$	29,004
Commercial loan interest rate derivatives	Other liabilities	76		648,456			—			(11,175		)	(11,175		)
Total customer position		235		$	1,563,728		$	29,004		$	(11,175	)	$	17,829
Webster with counterparty position:
Commercial loan interest rate derivatives	Other assets	111		$	914,044		$	8,944		$	(2,766	)	$	6,178
Commercial loan interest rate derivatives	Other liabilities	118		649,623			8,118			(20,094		)	(11,976		)
Futures contracts	Other liabilities	14		11,200,000			32			(259		)	(227		)
Total counterparty position		243		$	12,763,667		$	17,094		$	(23,119	)	$	(6,025	)
Webster reported the changes in the fair value of non-hedge accounting derivatives as a component of other non-interest income in the accompanying Condensed Consolidated Statements of Income as follows:
	Three months ended September 30,								Nine months ended September 30,
(In thousands)	2014				2013				2014				2013
Non-hedge derivatives, net	$	1,769			$	1,511			5,335				3,144
Futures contracts	(299		)		(450		)		(585		)		(290		)
Net increase to other non-interest income	$	1,470			$	1,061			$	4,750			$	2,854
Offsetting Derivatives
Webster has entered into transactions with counterparties that are subject to a master netting agreement. Hedge accounting positions are recorded on a gross basis in other assets for a gain position and in other liabilities for a loss position, while non-hedge accounting net positions are recorded in other assets for a net gain or in other liabilities for a net loss position in the accompanying Condensed Consolidated Balance Sheets.
The tables below present the financial assets and liabilities for non-customer derivative positions, including futures contracts, summarized by dealer counterparty or Derivative Clearing Organization ("DCO"):
	At September 30, 2014
	Notional Amount				Hedge Accounting Positions							Non-Hedge Accounting Positions						Total MTM(Loss) Gain			Cash Collateral Posted (Received)			Net Exposure (1)
(In thousands)					MTM Gain			MTM Loss				MTM Gain			MTM Loss
Dealer A	$	452,476			$	263		$	—			$	3,045		$	(7,455	)	$	(4,147	)	$	4,200		$	53
Dealer B	327,019				2,031			—				1,933			(6,853		)	(2,889		)	3,160			271
Dealer C	11,714				—			—				—			(908		)	(908		)	—			—
Dealer D	318,886				1,016			—				2,219			(1,107		)	2,128			(2,200		)	—
Dealer E	386,920				3,047			—				1,800			(1,518		)	3,329			(3,250		)	—
Dealer F (2)	8,908,942				—			(2,812		)		858			(6,916		)	(8,870		)	21,595			12,725
Total	$	10,405,957			$	6,357		$	(2,812	)		$	9,855		$	(24,757	)	$	(11,357	)	$	23,505
	At December 31, 2013
	Notional Amount				Hedge Accounting Positions							Non-Hedge Accounting Positions						Total MTM (Loss) Gain			Cash Collateral Posted (Received)			Net Exposure (1)
(In thousands)					MTM Gain			MTM Loss				MTM Gain			MTM Loss
Dealer A	$	387,258			$	730		$	—			$	4,643		$	(9,647	)	$	(4,274	)	$	4,300		$	26
Dealer B	322,888				615			—				3,475			(9,100		)	(5,010		)	4,940			—
Dealer C	14,477				—			—				—			(1,348		)	(1,348		)	—			—
Dealer D	291,627				1,734			—				4,108			(592		)	5,250			(5,300		)	—
Dealer E	372,771				2,290			(15		)		3,017			(1,743		)	3,549			(3,310		)	—
Dealer F (2)	11,749,646				1,212			(607		)		1,819			(657		)	1,767			7,485			9,252
Total	$	13,138,667			$	6,581		$	(622	)		$	17,062		$	(23,087	)	$	(66	)	$	8,115
(1) Net positive exposure represents over-collateralized loss positions which can be the result of DCO initial margin requirements posted in compliance with the Dodd-Frank Wall Street Reform and Consumer Protection Act.
(2) Dealer F represents Chicago Mercantile Exchange, our designated DCO.
Counterparty Credit Risk. Derivative contracts involve the risk of dealing with both bank customers and institutional derivative counterparties and their ability to meet contractual terms. The Company has International Swap Derivative Association ("ISDA") Master agreements, including a Credit Support Annex ("CSA"), with all derivative counterparties for non-cleared trades. The ISDA Master agreements provide that on each payment date, all amounts otherwise owing the same currency under the same transaction are netted so that only a single amount is owed in that currency. The ISDA provides, if the parties so elect, for such netting of amounts in the same currency among all transactions identified as being subject to such election that have common payment dates and booking offices. Under the CSA, daily net exposure in excess of a negotiated threshold is secured by posted cash collateral. The Company has negotiated a zero threshold with the majority of its approved financial institution counterparties. In accordance with Webster policies, institutional counterparties must be analyzed and approved through the Company’s credit approval process.
The Company’s credit exposure on interest rate derivatives with non-dealer counterparties is limited to the net favorable value, including accrued interest, reduced by the amount of collateral pledged by the counterparty. The Company's credit exposure related to derivatives with dealer counterparties is zero unless cash collateral exceeds the unfavorable market value.
In accordance with counterparty credit agreements and derivative clearing rules, the Company had approximately $23.5 million in net margin collateral posted with financial counterparties at September 30, 2014 which was comprised of approximately $29.0 million of margin collateral posted to financial counterparties or DCO and approximately $5.5 million received from financial counterparties. Collateral levels for approved financial institution counterparties are monitored daily and adjusted as necessary. In the event of default, should the collateral not be returned, the exposure would be offset by terminating the transaction.
The Company regularly evaluates the credit risk of its counterparties, taking into account likelihood of default, net exposures, and remaining contractual life, among other related factors. The Company's net current credit exposure relating to interest rate derivatives with Webster Bank customers was $35.2 million at September 30, 2014. In addition, the Company monitors potential future exposure, representing its best estimate of exposure to remaining contractual maturity. The potential future exposure relating to interest rate derivatives with Webster Bank customers totaled $14.2 million at September 30, 2014. The credit exposure is mitigated as transactions with customers are generally secured by the same collateral of the underlying transactions being hedged.
Futures Contracts Derivatives. Webster holds a notional $800 million short-sale of a one year strip of Fed funds futures contracts and continues to roll the maturities of these contracts. This transaction is designed to work in conjunction with floating rate assets with interest rate floors, which would not generate a benefit from an increase in short-term interest rates. Therefore, as the probability for rising short-term rates increases the notional amount would be increased and as the probability for rising short-term rates decreases the notional amount would be reduced. The fair value of these contracts is a net loss of $442 thousand and is reflected in other liabilities in the accompanying Condensed Consolidated Balance Sheets.
Mortgage Banking Derivatives. Forward sales of mortgage loans and MBS are utilized by Webster in its efforts to manage risk of loss associated with its mortgage loan commitments and mortgage loans held for sale. Prior to closing and funding certain single-family residential mortgage loans, interest rate lock commitments are generally extended to the borrowers. During the period from commitment date to closing date, Webster is subject to the risk that market rates of interest may change. If market rates rise, investors generally will pay less to purchase such loans causing a reduction in the anticipated gain on sale of the loans and possibly resulting in a loss. In an effort to mitigate such risk, forward delivery sales commitments are established, under which Webster agrees to deliver whole mortgage loans to various investors or issue MBS. At September 30, 2014, outstanding rate locks totaled approximately $44.8 million and the outstanding commitments to sell residential mortgage loans totaled approximately $58.7 million. Forward sales, which include mandatory forward commitments of approximately $56.7 million at September 30, 2014, establish the price to be received upon the sale of the related mortgage loan, thereby mitigating certain interest rate risk. There is, however, still certain execution risk specifically related to Webster’s ability to close and deliver to its investors the mortgage loans it has committed to sell. The interest rate locked loan commitments and forward sales commitments are recorded at fair value, with changes in fair value recorded as non-interest income in the accompanying Condensed Consolidated Statements of Income. At September 30, 2014 and December 31, 2013, the fair value of interest rate locked loan commitments and forward sales commitments totaled gains of $0.4 million and $0.5 million, respectively, and were recorded as a component of other assets in the accompanying Condensed Consolidated Balance Sheets.
Foreign Currency Derivatives. The Company enters into foreign currency forward contracts that are not designated for hedge accounting to minimize fluctuations of currency exchange rates on certain lending arrangements. The carrying amount and fair value of foreign currency forward contracts is immaterial at September 30, 2014.
Risk Participation Agreements. The Company enters into financial guarantees of performance on interest rate swap derivatives. The purchased (asset) or sold (liability) guarantee allows the Company to participate-in (for a fee received) or participate-out (for a fee paid), the risk associated with certain derivative positions executed with the borrower by a lead bank. The risk participation agreement guarantee is recorded on the balance sheet at fair value, with changes in fair value recognized in earnings each period. The notional amount and fair value of risk participation agreements remain immaterial at September 30, 2014.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements
	Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value is best determined using quoted market prices. However, in many instances, quoted market prices are not available. In such instances, fair values are determined using appropriate valuation techniques. Various assumptions and observable inputs must be relied upon in applying these techniques. Accordingly, the fair value estimates may not be realized in an immediate transfer of the respective asset or liability.
	Fair Value Hierarchy
	The three levels within the fair value hierarchy are as follows:
	•	Level 1: Valuation is based upon unadjusted quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.
	•	Level 2: Fair value is calculated using inputs other than quoted market prices that are directly or indirectly observable for the asset or liability. The valuation may rely on quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in inactive markets, inputs other than quoted prices that are observable for the asset or liability (such as interest rates, volatilities, prepayment speeds, credit ratings, etc.), or inputs that are derived principally or corroborated by market data, by correlation, or other means.
	•	Level 3: Inputs for determining the fair value of the respective assets or liabilities are not observable. Level 3 valuations are reliant upon pricing models and techniques that require significant management judgment or estimation.
	Categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	Available-for-Sale Investment Securities
	When quoted prices are available in an active market, the Company classifies securities within Level 1 of the valuation hierarchy. Level 1 securities include equity securities in financial institutions, U.S. Treasury Bills, and interest rate futures contracts.
	If quoted market prices are not available, the Company employs an independent pricing service that utilizes matrix pricing to calculate fair value. Such fair value measurements consider observable data such as dealer quotes, market spreads, cash flows, yield curves, live trading levels, trade execution data, market consensus prepayments speeds, credit information, and respective terms and conditions for debt instruments. Management maintains procedures to monitor the pricing service's assumptions and establishes processes to challenge the pricing service's valuations that appear unusual or unexpected. Level 2 securities include agency CMO, agency MBS, agency CMBS, CLO, corporate debt, single-issuer trust preferred securities, and CMBS.
	When a market is illiquid or there is a lack of transparency around the inputs to valuation, the securities are classified as Level 3, and reliance is placed upon internally developed models and management judgment for valuation.
	Derivative Instruments
	Fed funds futures contracts are valued based on unadjusted quoted prices in active markets and are classified within Level 1 of the fair value hierarchy. The Company's other derivative instruments are valued using third-party valuation software, which considers the present value of cash flows discounted using observable forward rate assumptions. The resulting fair values are validated against valuations performed by independent third parties and are classified within Level 2 of the fair value hierarchy. In determining if any fair value adjustments related to credit risk are required, Webster evaluates the credit risk of its counterparties by considering factors such as the likelihood of default by the counterparties, its net exposures, the remaining contractual life, as well as the amount of collateral securing the position. Webster reviews its counterparty exposure on a regular basis, and, when necessary, appropriate business actions are taken to adjust the exposure. When determining fair value, Webster applies the portfolio exception with respect to measuring counterparty credit risk for all of its derivative transactions subject to a master netting arrangement. The change in value of derivative assets and liabilities attributable to credit risk was not significant during the reported periods.
	Mortgage Banking Derivatives
	Mortgage-backed securities are utilized by the Company in its efforts to manage risk of loss associated with its mortgage loan commitments and mortgage loans held for sale. Prior to closing and funding certain single-family residential mortgage loans, an interest rate lock commitment is generally extended to the borrower. During the period from commitment date to closing date, the Company is subject to the risk that market rates of interest may change. If market rates rise, investors generally will pay less to purchase such loans resulting in a reduction in the gain on sale of the loans or, possibly, a loss. In an effort to mitigate such risk, forward delivery sales commitments are established, under which the Company agrees to deliver whole mortgage loans to various investors or issue mortgage-backed securities. The fair value of mortgage banking derivatives is determined based on current market prices for similar assets in the secondary market and, therefore, classified within Level 2 of the fair value hierarchy.
	Investments Held in Rabbi Trust
	Investments held in a Rabbi Trust primarily include mutual funds that invest in equity and fixed income securities. Shares of mutual funds are valued based on net asset value, which represents quoted market prices for the underlying shares held in the mutual funds. Therefore, investments held in the Rabbi Trust are classified within Level 1 of the fair value hierarchy. Webster has elected to measure the investments held in the Rabbi Trust at fair value. The Company consolidates the invested assets of the trust along with the total deferred compensation obligations and includes them in other assets and other liabilities, respectively, in the accompanying Condensed Consolidated Balance Sheets. Earnings in the Rabbi Trust, including appreciation or depreciation, are reflected as other non-interest income, and changes in the corresponding liability are reflected as compensation and benefits in the accompanying Condensed Consolidated Statements of Income. The cost basis of the investments held in the Rabbi Trust is $4.6 million as of September 30, 2014.
	Alternative Investments
	The Company generally records alternative investments at cost, subject to impairment testing. There are certain funds in which the ownership percentage is greater than 3% and are, therefore, recorded at fair value on a recurring basis based upon the net asset value of the respective fund. At September 30, 2014, alternative investments consisted of $0.5 million recorded at fair value and $16.2 million recorded at cost. These are non-public investments that cannot be redeemed since the Company’s investment is distributed as the underlying investments are liquidated. The alternative investments included at fair value are classified within Level 3 of the fair value hierarchy. The alternative investments that are carried at cost are considered to be measured at fair value on a non-recurring basis when there is impairment. The Company has $6.9 million in unfunded commitments remaining for its alternative investments as of September 30, 2014. See Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations, Investment Securities Portfolio section for a further discussion on the Company's alternative investments.
	A summary of fair value for assets and liabilities measured at fair value on a recurring basis is as follows:
		At September 30, 2014
	(In thousands)	Total			Quoted Prices in			Significant Other			Significant
					Active Markets for			Observable  Inputs			Unobservable  Inputs
					Identical Assets			(Level 2)			(Level 3)
					(Level 1)
	Financial assets held at fair value:
	Available-for-sale investment securities:
	U.S. Treasury Bills	$	525		$	525		$	—		$	—
	Agency CMO	638,223			—			638,223			—
	Agency MBS	1,090,820			—			1,090,820			—
	Agency CMBS	80,383			—			80,383			—
	CMBS	532,842			—			532,842			—
	CLO	380,511			—			380,511			—
	Pooled trust preferred securities	—			—			—			—
	Single issuer trust preferred securities	39,382			—			39,382			—
	Corporate debt	111,200			—			111,200			—
	Equity securities	—			—			—			—
	Total available-for-sale investment securities	2,873,886			525			2,873,361			—
	Derivative instruments	43,039			8			43,031			—
	Mortgage banking derivatives	387			—			387			—
	Investments held in Rabbi Trust	5,841			5,841			—			—
	Alternative investments	477			—			—			477
	Total financial assets held at fair value	$	2,923,630		$	6,374		$	2,916,779		$	477
	Financial liabilities held at fair value:
	Derivative instruments	$	24,820		$	450		$	24,370		$	—
	Total financial liabilities held at fair value	$	24,820		$	450		$	24,370		$	—
		At December 31, 2013
	(In thousands)	Total			Quoted Prices in			Significant Other			Significant
					Active Markets for			Observable  Inputs			Unobservable  Inputs
					Identical Assets			(Level 2)			(Level 3)
					(Level 1)
	Financial assets held at fair value:
	Available-for-sale investment securities:
	U.S. Treasury Bills	$	325		$	325		$	—		$	—
	Agency CMO	806,912			—			806,912			—
	Agency MBS	1,226,702			—			1,226,702			—
	Agency CMBS	70,977			—			70,977			—
	CMBS	464,274			—			464,274			—
	CLO	357,641			—			357,641			—
	Pooled trust preferred securities	28,490			—			—			28,490
	Single issuer trust preferred securities	34,935			—			34,935			—
Corporate debt	113,091			—			113,091			—
Equity securities	3,584			3,309			275			—
Total available-for-sale investment securities	3,106,931			3,634			3,074,807			28,490
Derivative instruments	41,795			32			41,763			—
Mortgage banking derivatives	540			—			540			—
Investments held in Rabbi Trust	6,097			6,097			—			—
Alternative investments	565			—			—			565
Total financial assets held at fair value	$	3,155,928		$	9,763		$	3,117,110		$	29,055
Financial liabilities held at fair value:
Derivative instruments	$	24,038		$	259		$	23,779		$	—
Total financial liabilities held at fair value	$	24,038		$	259		$	23,779		$	—
The following table presents the changes in Level 3 assets and liabilities that are measured at fair value on a recurring basis:
	Three months ended September 30,							Nine months ended September 30,
(In thousands)	2014			2013				2014			2013
Level 3, beginning of period	$	11,668		$	31,572			$	29,055		$	116,280
Transfers out of Level 3 (1)	—			—				—			(248,844		)
Change in unrealized loss included in other comprehensive income	3,216			7,194				3,410			14,194
Unrealized loss included in net income	(29		)	(70		)		(261		)	(355		)
Realized gain on sale of available for sale securities	(1,680		)	269				2,656			269
Purchases/capital calls	173			—				173			159,412
Sales/proceeds	(12,881		)	(7,740		)		(34,576		)	(7,740		)
Accretion/amortization	10			26				62			214
Calls/paydowns	—			(483		)		(42		)	(2,662		)
Level 3, end of period	$	477		$	30,768			$	477		$	30,768
-1	As of April 1, 2013, the CLO portfolio was transferred from Level 3 to Level 2 based on having more observable inputs in determining fair value. In prior quarters, the CLO portfolio was priced using average non-binding broker quotes. During the second quarter of 2013, the Company engaged a third-party pricing vendor to provide monthly fair value measurements. This methodology used is a combination of matrix pricing, observed market activity and metrics. Pricing inputs such as credit spreads are observable and market corroborated and, therefore, the CLO portfolio qualifies for Level 2 categorization. The market for CLO is an active market, and there is ample price transparency.
Assets Measured at Fair Value on a Non-Recurring Basis
Certain assets are measured at fair value on a non-recurring basis; that is, the assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). The following is a description of valuation methodologies used for assets measured on a non-recurring basis.
Loans Held for Sale
Loans held for sale are accounted for at the lower of cost or market and are considered to be recognized at fair value when they are recorded at below cost. The fair value of residential mortgage loans held for sale is based on quoted market prices of similar loans sold in conjunction with securitization transactions. Accordingly, such loans are classified as Level 2 measurements. On occasion, the loans held for sale portfolio includes commercial loans in which adjustments are required for changes in loan characteristics. When observable data is unavailable, such loans are classified within Level 3. At December 31, 2013, the Company transferred loans held for sale from Level 3 to Level 2 as the secondary market for securities backed by similar loan types is actively traded, providing readily observable market pricing to be used as inputs for the estimated fair value of these loans.
Impaired Loans and Leases
Impaired loans and leases for which repayment is expected to be provided solely by the value of the underlying collateral are considered collateral dependent and are valued based on the estimated fair value of such collateral using Level 3 inputs based on customized discounting criteria.
Other Real Estate Owned (OREO) and Repossessed Assets
The total book value of OREO and repossessed assets was $5.2 million at September 30, 2014. OREO and repossessed assets are accounted for at the lower of cost or market and are considered to be recognized at fair value when they are recorded at below cost. The fair value of OREO is based on independent appraisals or internal valuation methods, less estimated selling costs. The valuation may consider available pricing guides, auction results, and price opinions. Certain assets require assumptions about factors that are not observable in an active market in the determination of fair value and are classified as Level 3.
Mortgage Servicing Assets
Mortgage servicing assets are accounted for at cost, subject to impairment testing. When the carrying cost exceeds fair value, a valuation allowance is established to reduce the carrying cost to fair value. Fair value is calculated as the present value of estimated future net servicing income and relies on market based assumptions for loan prepayment speeds, servicing costs, discount rates, and other economic factors. As such, mortgage servicing assets are classified within Level 3 of the fair value hierarchy.
The table below presents the valuation methodology and unobservable inputs for Level 3 assets measured at fair value on a non-recurring basis at September 30, 2014:
(Dollars in thousands)
Asset	Fair Value			Valuation Methodology	Unobservable Inputs	Range of Inputs
Impaired loans and leases	$	40,927		Real Estate Appraisals	Discount for appraisal type	2% - 15%
					Discount for costs to sell	0% - 8%
Other real estate owned	$	831		Real Estate Appraisals	Discount for appraisal type	0% - 25%
					Discount for costs to sell	8%
Mortgage servicing assets	$	29,213		Discounted cash flow	Constant prepayment rate	6.8% - 25.3%
					Discount rates	1.4% - 3.7%
Fair Value of Financial Instruments
The Company is required to disclose the estimated fair value of financial instruments, both assets and liabilities, for which it is practicable to estimate fair value. The following is a description of valuation methodologies used for those assets and liabilities.
Cash, Due from Banks, and Interest-bearing Deposits
The carrying amount of cash, due from banks, and interest-bearing deposits is used to approximate fair value, given the short time frame to maturity and, as such, assets do not present unanticipated credit concerns. Cash, due from banks, and interest-bearing deposits are classified within Level 1 of the fair value hierarchy.
Held-to-Maturity Investment Securities
When quoted market prices are not available, the Company employs an independent pricing service to calculate fair value. Such fair value measurements consider observable data such as dealer quotes, market spreads, cash flows, yield curves, live trading levels, trade execution data, market consensus prepayments speeds, credit information, and respective terms and conditions for debt instruments. Webster has procedures to monitor the pricing service's assumptions and establishes processes to challenge the pricing service's valuations that appear unusual or unexpected. Held-to-Maturity investments which include agency CMO, agency MBS, agency CMBS, Municipal and Private Label MBS securities are classified within Level 2 of the fair value hierarchy.
Loans and Leases
The estimated fair value of loans and leases held for investment is calculated using a discounted cash flow method, using future prepayments and market interest rates inclusive of an illiquidity premium for comparable loans and leases. The associated cash flows are adjusted for credit and other potential losses. Fair value for impaired loans and leases is estimated using the net present value of the expected cash flows. Loans and leases are classified within Level 3 of the fair value hierarchy.
Deposit Liabilities
The fair value of demand deposits, savings accounts, and certain money market deposits is the amount payable on demand at the reporting date. The fair value of fixed-maturity certificates of deposit is estimated using the rates currently offered for deposits of similar remaining maturities. Deposit liabilities are classified within Level 2 of the fair value hierarchy.
Securities Sold Under Agreements to Repurchase and Other Borrowings
Carrying value is an estimate of fair value for those securities sold under agreements to repurchase and other borrowings that mature within 90 days. The fair values of all other borrowings are estimated using discounted cash flow analysis based on current market rates adjusted, as appropriate, for associated credit risks. Securities sold under agreements to repurchase and other borrowings are classified within Level 2 of the fair value hierarchy.
Federal Home Loan Bank Advances and Long-Term Debt
The fair value of Federal Home Loan Bank advances and long-term debt is estimated using a discounted cash flow technique. Discount rates are matched with the time period of the expected cash flow and are adjusted, as appropriate, to reflect credit risk. Federal Home Loan Bank advances and long-term debt are classified within Level 2 of the fair value hierarchy.
The estimated fair values of selected financial instruments are as follows:
	At September 30, 2014								At December 31, 2013
(In thousands)	Carrying				Fair Value				Carrying				Fair Value
	Amount								Amount
Financial Assets
Level 2 inputs:
Held-to-maturity investment securities	$	3,641,979			$	3,699,825			$	3,358,721			$	3,370,912
Loans held for sale	26,083				26,453				20,802				20,903
Level 3 inputs:
Loans and leases	13,357,020				13,377,939				12,547,203				12,515,714
Mortgage servicing assets (1)	19,651				29,213				20,983				29,150
Alternative investments	16,188				19,208				16,582				17,047
Financial Liabilities
Level 2 inputs:
Deposit liabilities, other than time deposits	$	13,244,672			$	13,244,672			$	12,627,276			$	12,627,276
Time deposits	2,302,246				2,317,764				2,227,144				2,250,141
Securities sold under agreements to repurchase and other borrowings	1,236,975				1,257,595				1,331,662				1,365,427
Federal Home Loan Bank advances (2)	2,290,204				2,301,591				2,052,421				2,063,312
Long-term debt (3)	226,208				223,278				228,365				221,613
-1	The carrying amount of mortgage servicing assets is net of $11 thousand and $0.2 million reserves at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.
-2	The carrying amount of FHLB advances is net of $43 thousand and $61 thousand in hedge accounting adjustments and discounts at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.
-3	The carrying amount of long-term debt is net of $1.1 million in discount at September 30, 2014 and $1.0 million in discount and hedge accounting adjustments, net at December 31, 2013. The estimated fair value does not include such adjustments.
Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. These estimates do not reflect any premium or discount that could result from offering for sale at one time the entire holdings or any part of a particular financial instrument. Because no active market exists for a significant portion of Webster’s financial instruments, fair value estimates are based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments, and other factors. These factors are subjective in nature and involve uncertainties and matters of significant judgment and, therefore, cannot be determined with precision. Changes in assumptions could significantly affect the estimates.

Pension_and_Other_Postretireme

Pension and Other Postretirement Benefits	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Pension and Other Postretirement Benefits	'
	Pension and Other Postretirement Benefits
	The following table summarizes the components of net periodic benefit cost:
		Three months ended September 30,
		Webster Pension						Webster SERP						Other Benefits
	(In thousands)	2014			2013			2014			2013			2014			2013
	Service cost	$	10		$	10		$	—		$	—		$	—		$	—
	Interest cost on projected benefit obligations	2,046			1,841			89			72			36			30
	Expected return on plan assets	(2,871		)	(2,779		)	—			—			—			—
	Amortization of prior service cost	—			—			—			—			18			18
	Recognized net loss	711			1,590			55			32			4			7
	Net periodic benefit cost (income)	$	(104	)	$	662		$	144		$	104		$	58		$	55
		Nine months ended September 30,
		Webster Pension						Webster SERP						Other Benefits
	(In thousands)	2014			2013			2014			2013			2014			2013
	Service cost	$	30		$	30		$	—		$	—		$	—		$	—
	Interest cost on benefit obligations	6,051			5,524			273			217			104			90
	Expected return on plan assets	(8,621		)	(8,336		)	—			—			—			—
	Amortization of prior service cost	—			—			—			—			55			54
	Recognized net loss	2,086			4,767			101			94			4			21
	Net periodic benefit cost (income)	$	(454	)	$	1,985		$	374		$	311		$	163		$	165
	The Webster Bank Pension Plan and the supplemental pension plans were frozen effective December 31, 2007. No additional benefits have been accrued since that time. Additional contributions to the Webster Bank Pension Plan will be made as deemed appropriate by management in conjunction with information provided by the Plan’s actuaries.
	Multiple-employer plan
	Webster Bank is a sponsor of a multiple-employer plan administered by Pentegra (the “Fund”) for the benefit of former employees of a bank acquired by Webster. The Fund does not segregate the assets or liabilities of its participating employers in the ongoing administration of this plan. According to the Fund’s administrators, as of July 1, 2014, the date of the latest actuarial valuation, Webster’s portion of the plan was overfunded by $0.3 million.
	The following table sets forth contributions and funding status of the Fund:
	(In thousands)	Contributions by Webster  Bank							Contributions by Webster  Bank							Funded Status of Plan
		Three Months Ended September 30,							Nine Months Ended September 30,
	EIN/Pension Plan Number	2014			2013				2014			2013				As of July 1, 2013
	13-5645888/333	$	—		$	60			$	674		$	534			At least 80 percent
	Multi-employer accounting is applied to the Fund. As a multiple-employer plan, there are no collective bargained contracts affecting the Fund's contribution or benefit provisions. All shortfall amortization bases are being amortized over seven years, as required by the Pension Protection Act. All benefit accruals were frozen as of September 1, 2004.

StockBased_Compensation_Plans

Stock-Based Compensation Plans	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock-Based Compensation Plans	'
	Stock-Based Compensation Plans
	Webster maintains stock-based compensation plans (collectively, the "Plans") under which non-qualified stock options, incentive stock options, restricted stock, restricted stock units, or stock appreciation rights may be granted to employees and directors. The Company believes these share awards better align the interests of its employees with those of its shareholders. Share awards are issued from available treasury shares. Stock-based compensation cost is recognized over the required service vesting period for the awards, based on the grant-date fair value, net of estimated forfeitures, and is included as a component of compensation and benefits reflected in non-interest expense. Awards to retirement eligible employees are subject to a one-year service vesting period.
	The following table provides a summary of stock-based compensation expense recognized in the accompanying Condensed Consolidated Statements of Income:
		Three months ended September 30,						Nine months ended September 30,
	(In thousands)	2014			2013			2014			2013
	Stock options	$	167		$	886		$	943		$	2,832
	Restricted stock	2,076			1,276			6,850			4,925
	Stock-based compensation	$	2,243		$	2,162		$	7,793		$	7,757
	The following table provides a summary of unrecognized stock-based compensation expense:
		At September 30, 2014
	(Dollars in thousands)	Unrecognized Compensation Expense			Weighted-Average Period To Be Recognized
	Stock options	$	654		1.3 years
	Restricted stock	$	11,659		2.0 years
	The following table provides a summary of the activity under the Plans for the nine months ended September 30, 2014:
		Restricted Stock Awards Outstanding															Stock Options Outstanding
		Time-Based											Performance-Based
		Number of		Weighted-Average			Number of		Weighted-Average				Number of		Weighted-Average		Number of		Weighted-Average
		Shares		Grant Date			Units		Grant Date				Shares		Grant Date		Shares		Exercise Price
				Fair Value					Fair Value						Fair Value
	Outstanding, at January 1, 2014	267,119		$	22.96		1,705		$	22.75			138,450		$	24.43	2,325,797		$	26.97
	Granted	215,412		29.65			13,678		29.34				146,248		29.94		—		—
	Exercised options	—		—			—		—				—		—		(108,841	)	15.98
	Vested restricted stock awards (1)	(166,008	)	24.68			(9,685	)	28.18				(113,394	)	25.84		—		—
	Forfeited	(21,941	)	25.27			—		—				(16,909	)	26.47		(94,380	)	35.3
	Outstanding, at September 30, 2014	294,582		$	26.71		5,698		$	29.34			154,395		$	28.4	2,122,576		$	27.16
	Options exercisable, at September 30, 2014																1,814,294		$	27.83
	Options expected to vest, at September 30, 2014																294,667		$	23.24
	(1) Vested for purposes of recording compensation expense.
	Time-based restricted stock awards vest over the applicable service period ranging from one to five years. The Plans limit the number of time-based awards that may be granted to an eligible individual in a calendar year to 100,000 shares. Compensation expense recorded over the vesting period is based on a fair value of the grant-date market price of the Company's common stock.
	Performance-based restricted stock awards vest after three years, with share quantity dependent on performance. Prior to January 1, 2014, awards vest in a range from zero to 200% and subsequent to that date, awards vest in a range from zero to 150% of the target number of shares under the grant. The performance-based shares granted in 2014 vest, based 50% upon Webster's ranking for total shareholder return versus Webster's fourteen-bank compensation peer group companies and 50% upon Webster's return on equity, over the three year vesting period. The fourteen-bank compensation peer group companies are utilized because they represent the mix of size and type of financial institutions that best compare with Webster. The Company records compensation expense over the vesting period, based on a fair value calculated using the Monte-Carlo simulation model, which allows for the incorporation of the performance condition for the 50% of the performance-based shares tied to total shareholder return versus the fourteen-bank compensation peer group, and based on a fair value of the market price on the date of grant for the remaining 50% of the performance-based shares tied to Webster's return on equity. Compensation expense is subject to adjustment based on management's assessment of Webster's return on equity performance relative to the target number of shares condition. Dividends are accrued on the performance-based shares and paid when the performance target is met.
	Stock option awards have an exercise price equal to the market price of Webster's stock on the date of grant and vest over periods ranging from three to four years. Each option grants the holder the right to acquire a share of Webster common stock over a contractual life of up to ten years. There were no stock options granted in 2014. At September 30, 2014, stock options outstanding included 1,942,570 non-qualified and 180,006 incentive options.

Segment_Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Segment Reporting	'
	Segment Reporting
	Webster’s operations are divided into three reportable segments that represent its core businesses – Commercial Banking, Community Banking, and Other. Community Banking includes the operating segments of Webster's Personal Bank and Business Banking, and Other includes HSA Bank and Private Banking. These segments reflect how executive management responsibilities are assigned by the chief operating decision maker for each of the core businesses, the products and services provided, and the type of customer served and reflect how discrete financial information is currently evaluated. The Company’s Treasury unit and consumer liquidating portfolio are included in the Corporate and Reconciling category along with the amounts required to reconcile profitability metrics to GAAP reported amounts.
	Webster’s business segment results are intended to reflect each segment as if it were a stand-alone business. Webster uses an internal profitability reporting system to generate information by operating segment, which is based on a series of management estimates and allocations regarding funds transfer pricing, the provision for loan and lease losses, non-interest expense, income taxes, and equity capital. These estimates and allocations, certain of which are subjective in nature, are continually being reviewed and refined. Changes in estimates and allocations that affect the reported results of any operating segment do not affect the consolidated financial position or results of operations of Webster as a whole. The full profitability measurement reports, which are prepared for each operating segment, reflect non-GAAP reporting methodologies. The differences between the full profitability and GAAP measures are reconciled in the Corporate and Reconciling category.
	The Company uses a matched maturity funding concept, called funds transfer pricing (“FTP”), to allocate interest income and interest expense to each business while also transferring the primary interest rate risk exposures to the Corporate and Reconciling category. The allocation process considers the specific interest rate risk and liquidity risk of financial instruments and other assets and liabilities in each line of business. The “matched maturity funding concept” considers the origination date and the earlier of the maturity date or the repricing date of a financial instrument to assign an FTP rate for loans and deposits originated each day. Loans are assigned an FTP rate for funds “used” and deposits are assigned an FTP rate for funds “provided.” This process is executed by the Company’s Financial Planning and Analysis division, and is overseen by the Company’s Asset/Liability Committee ("ALCO").
	Webster attributes the provision for loan and lease losses to each segment based on management’s estimate of the inherent loss content in each of the specific loan and lease portfolios. Provision expense for certain elements of risk that are not deemed specifically attributable to a business segment, such as environmental factors, and provision for the consumer liquidating portfolio, is shown as part of the Corporate and Reconciling category. For the three and nine months ending September 30, 2014 and 2013, 100.3%, 110.0%, 125.0% and 111.6% respectively, of the provision for loan and lease losses is specifically attributable to business segments and reported accordingly.
	Webster allocates a majority of non-interest expense to each business segment using a full-absorption costing process. Costs, including corporate overhead, are analyzed, pooled by process, and assigned to the appropriate business segment. Income tax expense is allocated to each business segment based on the effective income tax rate for the period shown.
	The following tables present the results for Webster’s business segments and incorporate the allocation of the provision for loan and lease losses and income tax expense to each of Webster’s business segments for the periods presented:
		Three months ended September 30, 2014
	(In thousands)	Commercial		Community Banking		Other		Segment Totals		Corporate and			Consolidated
		Banking								Reconciling			Total
	Net interest income (loss)	$	61,249	$	88,602	$	12,117	$	161,968	$	(4,598	)	$	157,370
	Provision (benefit) for loan and lease losses	3,340		6,159		26		9,525		(25		)	9,500
	Net interest income (loss) after provision for loan and lease losses	57,909		82,443		12,091		152,443		(4,573		)	147,870
	Non-interest income	8,861		27,307		9,471		45,639		5,270			50,909
	Non-interest expense	25,445		79,735		14,807		119,987		4,655			124,642
	Income (loss) before income tax expense	41,325		30,015		6,755		78,095		(3,958		)	74,137
	Income tax expense (benefit)	13,148		9,588		2,162		24,898		(1,219		)	23,679
	Net income (loss)	$	28,177	$	20,427	$	4,593	$	53,197	$	(2,739	)	$	50,458
		Three months ended September 30, 2013
	(In thousands)	Commercial		Community Banking		Other		Segment Totals		Corporate and			Consolidated
		Banking								Reconciling			Total
	Net interest income (loss)	$	56,430	$	87,949	$	10,733	$	155,112	$	(5,125	)	$	149,987
	Provision for loan and lease losses	7,032		3,570		22		10,624		(2,124		)	8,500
	Net interest income (loss) after provision for loan and lease losses	49,398		84,379		10,711		144,488		(3,001		)	141,487
	Non-interest income	8,818		25,387		8,083		42,288		3,969			46,257
	Non-interest expense	24,647		82,748		11,913		119,308		2,973			122,281
	Income (loss) before income tax expense	33,569		27,018		6,881		67,468		(2,005		)	65,463
	Income tax expense (benefit)	9,347		7,504		1,941		18,792		(634		)	18,158
	Net income (loss)	$	24,222	$	19,514	$	4,940	$	48,676	$	(1,371	)	$	47,305
		Nine months ended September 30, 2014
	(In thousands)	Commercial		Community Banking		Other		Segment		Corporate and			Consolidated
		Banking						Totals		Reconciling			Total
	Net interest income (loss)	$	175,058	$	263,893	$	35,192	$	474,143	$	(6,350	)	$	467,793
	Provision (benefit) for loan and lease losses	18,031		12,156		334		30,521		(2,771		)	27,750
	Net interest income (loss) after provision for loan and lease losses	157,027		251,737		34,858		443,622		(3,579		)	440,043
	Non-interest income	24,761		77,571		29,089		131,421		16,912			148,333
	Non-interest expense	76,579		241,314		43,050		360,943		10,901			371,844
	Income before income tax expense	105,209		87,994		20,897		214,100		2,432			216,532
	Income tax expense	32,940		27,551		6,543		67,034		761			67,795
	Net income	$	72,269	$	60,443	$	14,354	$	147,066	$	1,671		$	148,737
		Nine months ended September 30, 2013
	(In thousands)	Commercial		Community Banking		Other		Segment		Corporate and			Consolidated
		Banking						Totals		Reconciling			Total
	Net interest income (loss)	$	161,008	$	259,037	$	30,008	$	450,053	$	(7,209	)	$	442,844
	Provision (benefit) for loan and lease losses	11,449		15,816		72		27,337		(2,837		)	24,500
	Net interest income (loss) after provision for loan and lease losses	149,559		243,221		29,936		422,716		(4,372		)	418,344
	Non-interest income	20,537		87,654		24,579		132,770		14,016			146,786
	Non-interest expense	74,068		251,759		37,112		362,939		8,481			371,420
	Income before income tax expense	96,028		79,116		17,403		192,547		1,163			193,710
	Income tax expense	28,710		23,654		5,203		57,567		348			57,915
	Net income	$	67,318	$	55,462	$	12,200	$	134,980	$	815		$	135,795
		Total Assets
	(In thousands)	Commercial		Community Banking		Other		Segment Totals		Corporate and			Consolidated
		Banking								Reconciling			Total
	At September 30, 2014	$	6,251,726	$	8,062,212	$	391,280	$	14,705,218	$	7,121,664		$	21,826,882
	At December 31, 2013	$	5,682,129	$	7,809,343	$	365,863	$	13,857,335	$	6,995,664		$	20,852,999

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Lease Commitments. At September 30, 2014, Webster was obligated under various non-cancelable operating leases for properties used as banking and other office facilities. The leases contain renewal options and escalation clauses which provide for increased rental expense, or equipment replaced with new leased equipment, as the leases expire. Rental expense under leases was $5.2 million and $15.3 million for both the three and nine months ended September 30, 2014 and 2013, respectively, and is recorded as a component of occupancy expense in the accompanying Condensed Consolidated Statements of Income. Rental income from sub-leases on certain of these properties is also recorded as a component of occupancy expense while rental income under various non-cancelable operating leases for properties owned is recorded as a component of other non-interest income in the accompanying Condensed Consolidated Statements of Income. Rental income was $0.2 million and $0.6 million and $0.2 million and $0.7 million for the three and nine months ended September 30, 2014 and 2013, respectively. There has been no significant change in future minimum lease payments payable since December 31, 2013. See Webster's 2013 Form 10-K for additional information regarding these commitments.
	Credit-Related Financial Instruments. The Company is a party to credit-related financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit, standby letters of credit, and commercial letters of credit. Such commitments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the balance sheet. The Company’s exposure to credit loss is represented by the contractual amount of these commitments as it is for on-balance sheet instruments.
	The following table summarizes outstanding contract amounts for off-balance sheet instruments that represent credit risk:
	(In thousands)	At September 30,		At December 31,
		2014		2013
	Unused commitments to extend credit	$	4,390,764	$	4,127,089
	Standby letters of credit	146,689		135,761
	Commercial letters of credit	26,025		13,621
	Total financial instruments with off-balance sheet risk	$	4,563,478	$	4,276,471
	Unused commitments to extend credit. The Company makes commitments under various terms to lend funds to customers. These commitments include revolving credit arrangements, term loan commitments, and short-term borrowing agreements. Many of these loans have fixed expiration dates or other termination clauses where a fee may be required. Since commitments are expected to expire without being funded, the total commitment amounts do not necessarily represent future liquidity requirements.
	Standby letters of credit. Standby letters of credit commit the Company to make payments on behalf of customers if certain specified future events occur. The Company has recourse against the customer for any amount required to be paid to a third party under a standby letter of credit. Historically, a large percentage of standby letters of credit expire without being funded. The contractual amount of standby letters of credit represents the maximum potential amount of future payments the Company could be required to make and represents the Company's maximum credit risk.
	Commercial letters of credit. Commercial letters of credit are issued to facilitate domestic or foreign trade transactions for customers. As a general rule, drafts will be drawn when the goods underlying the transaction are in transit.
	The reserve for unfunded credit commitments is reported as a component of accrued expenses and other liabilities in the accompanying Condensed Consolidated Balance Sheets. The following table provides activity details for the Company’s reserve for unfunded credit commitments:
		Three months ended September 30,				Nine months ended
						September 30,
	(In thousands)	2014		2013		2014		2013
	Balance, beginning of period	$	4,749	$	4,593	$	4,384	$	5,662
	Provision (benefit)	273		64		638		(1,005		)
	Balance, end of period	$	5,022	$	4,657	$	5,022	$	4,657
	Litigation Reserves. Webster is involved in routine legal proceedings occurring in the ordinary course of business and is subject to loss contingencies related to such litigation and claims arising therefrom. Webster evaluates these contingencies based on information currently available, including advice of counsel and assessment of available insurance coverage. Webster establishes accruals for litigation and claims when a loss contingency is considered probable and the related amount is reasonably estimable. These accruals are periodically reviewed and may be adjusted as circumstances change. Webster also estimates certain loss contingencies for possible litigation and claims, whether or not there is an accrued probable loss. Webster believes it has defenses to all the claims asserted against it in existing litigation matters and intends to defend itself in all matters.
	Based upon its current knowledge, after consultation with counsel and after taking into consideration its current litigation accruals, Webster believes that as of September 30, 2014 any reasonably possible losses, in addition to amounts accrued, are not material to Webster’s consolidated financial condition. However, in light of the uncertainties involved in such actions and proceedings, there is no assurance that the ultimate resolution of these matters will not significantly exceed the reserves currently accrued by Webster or that the Company’s litigation reserves will not need to be adjusted in future periods. Such an outcome could be material to the Company’s operating results in a particular period, depending on, among other factors, the size of the loss or liability imposed and the level of the Company’s income for that period.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Presentation	'
	Basis of Presentation. The Condensed Consolidated Financial Statements include the accounts of Webster Financial Corporation and all other entities in which it has a controlling financial interest. All significant intercompany balances and transactions have been eliminated in consolidation. Webster's accounting and financial reporting policies conform, in all material respects, to U.S. generally accepted accounting principles (“GAAP”) and to general practices within the financial services industry.
	The Company determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity (“VIE”) under GAAP. Voting interest entities are entities in which the total equity investment at risk is sufficient to enable the entity to finance itself independently and provides the equity holder with the obligation to absorb losses, the right to receive residual returns and the right to make decisions about the entity’s activities. The Company consolidates voting interest entities in which it has at least a majority of the voting interest. VIEs are entities that lack one or more of the characteristics of a voting interest entity. A controlling financial interest in a VIE is present when the Company has both the power and ability to direct the activities of the VIE that most significantly impact the VIE's economic performance and an obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE.
	The Company owns the common stock of a trust which has issued trust preferred securities. The trust is a VIE in which the Company is not the primary beneficiary and, therefore, is not consolidated. The trust's only assets are junior subordinated debentures issued by the Company, which were acquired by the trust using the proceeds from the issuance of the trust preferred securities and common stock. The junior subordinated debentures are included in long-term debt and the Company’s equity interest in the trust is included in other assets in the accompanying Condensed Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is reported in interest expense on long-term debt in the accompanying Condensed Consolidated Statements of Income.
	Certain prior period amounts have been reclassified to conform to the current year's presentation. These reclassifications had no impact on the Company's consolidated financial position, results of operations or net change in cash or cash equivalents.
Use of Estimates	'
	Use of Estimates. The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of these Condensed Consolidated Financial Statements. Actual results could differ from those estimates. The allowance for loan and lease losses, the fair value measurements of financial instruments and evaluation of investments for other-than-temporary impairment, the valuation of goodwill, the deferred tax asset valuation allowance, and pension and other postretirement benefits, as well as the status of contingencies, are particularly subject to change.
Cash Equivalents and Cash Flows	'
	Cash Equivalents and Cash Flows. For the purposes of the Condensed Consolidated Statements of Cash Flows, cash equivalents include cash on hand and due from banks and, interest-bearing deposits at the Federal Reserve. Cash equivalents have a maturity of three months or less.
	Cash flows from loans, either originated or acquired, are classified at that time according to management's original intent to either sell or hold the loan for the foreseeable future. When management's intent is to sell the loan, the cash flows of that loan are presented as operating cash flows. When management's intent is to hold the loan for the foreseeable future, the cash flows of that loan are presented as investing cash flows.
Investment Securities	'
	Investment Securities. Investment securities are classified as available-for-sale or held-to-maturity at the time of purchase and any subsequent change to classification is reviewed for compliance with corporate objectives and accounting policy. Debt securities classified as held-to-maturity are those which Webster has the ability and intent to hold to maturity. Securities in the held-to-maturity portfolio are recorded at amortized cost net of unamortized premiums and discounts. Discount accretion income and premium amortization expense are recognized as interest income according to a constant yield methodology. Securities classified as available-for-sale are recorded at fair value with unrealized gains and losses, net of taxes, recorded as a component of other comprehensive income (“OCI”). Securities transferred from available-for-sale to held-to-maturity are recorded at fair value at the time of transfer and the respective gain or loss is recorded as a separate component of OCI and then amortized as an adjustment to interest income over the remaining life of the security.
	All securities classified as available-for-sale or held-to-maturity that are in an unrealized loss position are evaluated for other-than-temporary impairment ("OTTI") on a quarterly basis. The evaluation considers several qualitative factors, including the period of time the security has been in a loss position, in addition to the amount of the unrealized loss. If the Company intends to sell the security or it is more than likely the Company will be required to sell the security prior to recovery of its amortized cost basis, the security is written down to fair value and the loss is recorded in non-interest income in the accompanying Condensed Consolidated Statements of Income. If the Company does not intend to sell the security and it is more likely than not that the Company will not be required to sell the security prior to recovery of its amortized cost basis, only the credit component of any impairment charge to a debt security would be recognized as a loss in non-interest income in the accompanying Condensed Consolidated Statements of Income. The remaining loss component would be recorded to accumulated other comprehensive income ("AOCI"). A decline in the value of an equity security that is considered OTTI is recorded as a loss in non-interest income in the accompanying Condensed Consolidated Statements of Income.
	The specific identification method is used to determine realized gains and losses on sales of securities.
Loans Held for Sale	'
	Loans Held for Sale. Loans typically are classified as held for sale upon origination based on management's intent to sell such loans. Loans held for sale are carried at the lower of cost or fair value. Non-residential mortgage loans held for sale are carried at the lower of cost or fair value and are valued on an individual asset basis. Any cost amount in excess of fair value is recorded as a valuation allowance and recognized as a reduction of other income in the Condensed Consolidated Statements of Income. Gains or losses on the sale of loans held for sale are recorded as non-interest income. Direct loan origination costs and fees are deferred and are recognized as part of the gain or loss at the time of sale.
Loans	'
	Loans. Loans are stated at the principal amount outstanding, net of amounts charged off, unamortized premiums and discounts, and deferred loan fees and/or costs which are recognized as yield adjustments using the interest method. These yield adjustments are amortized over the contractual life of the related loans adjusted for estimated prepayments when applicable. Interest on loans is credited to interest income as earned based on the interest rate applied to principal amounts outstanding.
	Loans are placed on non-accrual status when collection of principal and interest in accordance with contractual terms is doubtful. A loan is transferred to a non-accrual basis generally when principal or interest payments become 90 days delinquent, unless the loan is well secured and in process of collection, or sooner if management concludes circumstances indicate that the borrower may be unable to meet contractual principal or interest payments. Residential real estate and consumer loans are placed on non-accrual status at 90 days past due, or at the date when the Company is notified that the borrower is discharged in bankruptcy. A charge-off is recorded at 180 days if the loan balance exceeds the fair value of the collateral less costs to sell. Commercial, commercial real estate, and equipment finance loans are subject to a detailed review when 90 days past due to determine accrual status, or when payment is uncertain and a specific consideration is made to put a loan or lease on non-accrual status.
	When a loan is placed on non-accrual status, the accrual of interest is discontinued and any unpaid accrued interest is reversed and charged against interest income. If ultimate repayment of a non-accrual loan is expected, any payments received are applied in accordance with contractual terms. If ultimate repayment is not expected on commercial, commercial real estate, and equipment finance loans, any payment received on a non-accrual loan is applied to principal until the unpaid balance has been fully recovered. Any excess is then credited to interest income when received. If the Company determines, through a current valuation analysis, that principal can be repaid on residential real estate and consumer loans, interest payments may be taken into income as received on a cash basis. Except for loans discharged under Chapter 7 of the Bankruptcy Code, loans are removed from non-accrual status when they become current as to principal and interest or demonstrate a period of performance under contractual terms and, in the opinion of management, are fully collectible as to principal and interest. Pursuant to regulatory guidance, a Chapter 7 discharged bankruptcy loan is removed from non-accrual status when the bank expects full repayment of the remaining pre-discharged contractual principal and interest, is a closed-end amortizing loan, fully collateralized, and post-discharge had at least six consecutive months of current payments.
Allowance for Loan and Lease Losses and Reserve for Unfunded Commitments	'
	Allowance for Loan and Lease Losses. The allowance for loan and lease losses ("ALLL") is a reserve established through a provision for loan and lease losses charged to expense and represents management’s best estimate of probable losses that may be incurred within the existing loan and lease portfolio as of the balance sheet date. The level of the allowance reflects management’s view of trends in losses, current portfolio quality, and present economic, political, and regulatory conditions. Portions of the allowance may be allocated for specific loans and leases; however, the entire allowance is available for any loan or lease that is charged off. A charge-off is recorded on a case-by-case basis when all or a portion of the loan or lease is deemed to be uncollectible. Back-testing is performed to compare original estimated losses and actual observed losses, resulting in ongoing refinements. While management utilizes its best judgment based on the information available at the time, the ultimate adequacy of the allowance is dependent upon a variety of factors that are beyond the Company’s control, which include the performance of the Company’s portfolio, economic conditions, interest rate sensitivity, and the view of the regulatory authorities regarding loan classifications.
	The ALLL consists of the following three elements: (i) specific valuation allowances established for probable losses on impaired loans and leases; (ii) quantitative valuation allowances calculated using loss experience for like loans and leases with similar characteristics and trends, adjusted, as necessary, to reflect the impact of current conditions; and (iii) qualitative factors determined based on general economic conditions and other factors that may be internal or external to the Company.
	Loans and leases are considered impaired when, based on current information and events, it is probable the Company will be unable to collect all amounts due in accordance with the original contractual terms of the loan agreement, including scheduled principal and interest payments. Impairment is evaluated on a pooled basis for smaller-balance homogeneous residential and consumer loans. Commercial, commercial real estate, and equipment financing loans and leases over a specific dollar amount and all troubled debt restructurings ("TDR") are evaluated individually for impairment. A loan identified as a TDR is considered an impaired loan for the entire term of the loan, with few exceptions. If a loan is impaired, a specific valuation allowance may be established, and the loan is reported net, at the present value of estimated future cash flows using the loan’s original interest rate or at the fair value of collateral less cost to sell if repayment is expected from collateral liquidation. Interest payments on non-accruing impaired loans are typically applied to principal unless collectability of the principal amount is reasonably assured, in which case interest is recognized on a cash basis. Impaired loans, or portions thereof, are charged off when deemed uncollectible. Factors considered by management in determining impairment include payment status, collateral value, discharged bankruptcy, and the likelihood of collecting scheduled principal and interest payments. Consumer modified loans are analyzed for re-default probability, which is considered when determining the impaired reserve for ALLL. The current or weighted average (for multiple notes within a commercial borrowing arrangement) interest rate of the loan is used as the discount rate when the interest rate floats with a specified index. A change in terms or payments would be included in the impairment calculation.
	Reserve for Unfunded Commitments. The reserve for unfunded commitments provides for probable losses inherent with funding the unused portion of legal commitments available to lend. The unfunded reserve calculation includes factors that are consistent with ALLL methodology for funded loans using the loss given default, probability of default and a draw down factor applied to the underlying borrower risk and facility grades. Changes in the reserve for unfunded credit commitments, included within other liabilities, are reported as a component of other expense in the accompanying Condensed Consolidated Statements of Income.
Troubled Debt Restructurings	'
	Troubled Debt Restructurings. A modified loan is considered a TDR when the following two conditions are met: (i) the borrower is experiencing financial difficulties and (ii) the modification constitutes a concession. The Company considers all aspects of the restructuring in determining whether a concession has been granted, including the debtor's ability to access funds at a market rate. In general, a concession exists when the modified terms of the loan are more attractive to the borrower than standard market terms. Modified terms are dependent upon the financial position and needs of the individual borrower. The most common types of modifications include covenant modifications, forbearance and/or other concessions. Loans for which the borrower has been discharged under Chapter 7 bankruptcy are considered collateral dependent TDRs, impaired at the date of discharge, and charged down to the fair value of collateral less cost to sell, if management considers that loss potential likely exists.
	The Company’s policy is to place consumer loan TDRs, except those that were performing prior to TDR status, on non-accrual status for a minimum period of six months. Commercial TDRs are evaluated on a case-by-case basis for determination of whether or not to place on non-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. Initially, all TDRs are reported as impaired. Generally, TDRs are classified as impaired loans and reported as TDRs for the remaining life of the loan. Impaired and TDR classification, may be removed if the borrower demonstrates compliance with the modified terms for a minimum of six months and through one fiscal year-end and the restructuring agreement specifies a market rate of interest equal to that which would be provided to a borrower with similar credit at the time of restructuring. In the limited circumstance that a loan is removed from TDR classification it is the Company’s policy to continue to base its measure of loan impairment on the contractual terms specified by the loan agreement.
Transfers and Servicing of Financial Assets	'
	Transfers and Servicing of Financial Assets. Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is generally considered to have been surrendered when (i) the transferred assets are legally isolated from the Company or its consolidated affiliates, even in bankruptcy or other receivership, (ii) the transferee has the right to pledge or exchange the assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Company, and (iii) the Company does not maintain the obligation or unilateral ability to reclaim or repurchase the assets.
	The Company sells financial assets in the normal course of business, the majority of which are residential mortgage loan sales primarily to government-sponsored enterprises through established programs, commercial loan sales through participation agreements, and other individual or portfolio loan and securities sales. In accordance with accounting guidance for asset transfers, the Company considers any ongoing involvement with transferred assets in determining whether the assets can be derecognized from the balance sheet. With the exception of servicing and certain performance-based guarantees, the Company’s continuing involvement with financial assets sold is minimal and generally limited to market customary representation and warranty clauses.
	When the Company sells financial assets, it may retain servicing rights and/or other interests in the financial assets. The gain or loss on sale depends on the previous carrying amount of the transferred financial assets and the consideration received and any liabilities incurred in exchange for the transferred assets. Upon transfer, any servicing assets and other interests held by the Company are carried at the lower of cost or fair value.
Recently Issued Accounting Standards Update and Recently Issued Accounting Standards Updates	'
	Recently Adopted Accounting Standards Updates
	ASU No. 2013-11 - Income Taxes (Topic 740) - "Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force)." The ASU requires an entity to present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward, as applicable. To the extent a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit shall be presented in the financial statements as a liability and shall not be combined with deferred tax assets. This update was adopted effective January 1, 2014 and will be applied prospectively; however, its netting provisions are consistent with the Company’s previous presentation, as applicable, and as a result do not require additional disclosures.
	Recently Issued Accounting Standards Updates
	ASU No. 2014-01 - Investments - Equity Method and Joint Ventures (Topic 323) - "Accounting for Investments in Qualified Affordable Housing Projects (a consensus of the FASB Emerging Issues Task Force)." The ASU permits an entity to make an accounting policy election to account for its investment in qualified affordable housing projects using the proportional amortization method if certain conditions are met. Under the proportionate amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). The decision to apply the proportionate amortization method of accounting should be applied consistently to all qualifying affordable housing project investments. A reporting entity that uses the effective yield or other method to account for its investments in qualified affordable housing projects before the date of adoption may continue to apply such method to those preexisting investments. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-04, Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - "Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure (a consensus of the FASB Emerging Issues Task Force)." The ASU clarifies that an in substance repossession or foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (i) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (ii) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar agreement. In addition, the amendments require disclosure of both the amount of foreclosed residential real estate property held by the creditor and the recorded investment in consumer mortgage loans collateralized by residential real estate property that are in the process of foreclosure in accordance with local requirements of the applicable jurisdiction. An entity can elect to adopt the amendments using either a modified retrospective method or a prospective transition method. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-09 - Revenue from Contracts with Customers (Topic 606). The ASU establishes a single comprehensive model for an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled, and will supersede nearly all existing revenue recognition guidance, to clarify and converge revenue recognition principles under US GAAP and IFRS. The update outlines five steps to recognizing revenue: (i) identify the contracts with the customer; (ii) identify the separate performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the separate performance obligations; (v) recognize revenue when each performance obligation is satisfied. The update requires more comprehensive disclosures, relating to quantitative and qualitative information for amounts, timing, the nature and uncertainty of revenue, and cash flows arising from contracts with customers, which will mainly impact construction and high-tech industries. The most significant potential impact to banking entities relates to less prescriptive derecognition requirements on the sale of OREO property. The amendments are effective for annual and interim periods beginning after January 1, 2017. An entity may elect either a full retrospective or a modified retrospective application. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-11 - Transfers and Servicing (Topic 860) - “Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures.” The ASU requires two accounting changes: (i) the accounting for repurchase-to-maturity transactions are to be accounted for as secured borrowings; (ii) repurchase financing arrangements, separate accounting is required for a transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty, which will result in secured borrowing accounting for the repurchase agreement. Additionally, disclosure requirements have been expanded to include a disaggregation of collateral used for secured borrowings, and contractual maturity disclosure has been expanded to interim periods. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-12, Compensation-Stock Compensation (Topic 718) - “Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period (a consensus of the FASB Emerging Issues Task Force).” The ASU provides explicit guidance to account for a performance target that could be achieved after the requisite service period as a performance condition. For awards within the scope of this Update, the Task Force decided that an entity should apply existing guidance in Topic 718 as it relates to share-based payments with performance conditions that affect vesting. Consistent with that guidance, performance conditions that affect vesting should not be reflected in estimating the fair value of an award at the grant date. Compensation cost should be recognized when it is probable that the performance target will be achieved and should represent the compensation cost attributable to the period for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The amendments are effective for annual and interim periods beginning after January 1, 2016. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-14, Receivables-Troubled Debt Restructurings by Creditors (Subtopic 310-40) - "Classification of Certain Government-Guaranteed Residential Mortgage Loans upon Foreclosure (a consensus of the FASB Emerging Issues Task Force)." The ASU has been issued to reduce diversity in practice in the classification of foreclosed residential mortgage loans held by creditors that are fully guaranteed under certain government programs, including the Federal Housing Administration guarantees. A residential mortgage loan would be derecognized and a separate other receivable would be recognized upon foreclosure if the loan has both of the following characteristics: (i) the loan has a government guarantee that is not separable from the loan before foreclosure entitling the creditor to the full unpaid principal balance of the loan; and (ii) at the time of foreclosure, the creditor has the intent to make a claim on the guarantee and the ability to recover the full unpaid principal balance of the loan through the guarantee. Notably, upon foreclosure, the separate other receivable would be measured based on the current amount of the loan balance expected to be recovered under the guarantee. The amendments are effective for annual and interim periods beginning after January 1, 2015. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.
	ASU No. 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40) - "Disclosure of Uncertainties About an Entity's Ability to Continue as a Going Concern." The ASU has been issued to require an entity to evaluate going concern uncertainties by assessing information about conditions and events that exist at the date the financial statements are issued and provide footnote disclosures when it is either (i) more likely than not that the entity will be unable to meet its obligations within twelve months after the financial statement date without taking actions outside the ordinary course of business, or (ii) known or probable that the entity will be unable to meet its obligations within twenty-four months after the financial statement date without taking actions outside the ordinary course of business. The amendments are effective for annual periods beginning after January 1, 2017 and also for interim periods beginning after January 1, 2018. The Company does not expect the application of this guidance to have a material impact on the Company's financial statements.

Investment_Securities_Tables

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2014
Investments, Debt and Equity Securities [Abstract]	'
Summary of Investment Securities	'
	Summaries of the amortized cost, carrying value, and fair value of Webster’s investment securities are presented below:
		At September 30, 2014
					Recognized in OCI									Not Recognized in OCI
	(In thousands)	Amortized			Gross			Gross			Carrying			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized			Value			Unrealized			Unrealized
					Gains			Losses						Gains			Losses
	Available-for-sale:
	U.S. Treasury Bills	$	525		$	—		$	—		$	525		$	—		$	—		$	525
	Agency collateralized mortgage obligations (“CMO”)	628,737			10,543			(1,057		)	638,223			—			—			638,223
	Agency mortgage-backed securities (“MBS”)	1,103,345			11,014			(23,539		)	1,090,820			—			—			1,090,820
	Agency commercial mortgage-backed securities (“ACMBS”)	80,732			—			(349		)	80,383			—			—			80,383
	Commercial mortgage-backed securities (“CMBS”)	510,922			21,975			(55		)	532,842			—			—			532,842
	Collateralized loan obligations ("CLO") (1)	379,741			912			(142		)	380,511			—			—			380,511
	Pooled trust preferred securities	—			—			—			—			—			—			—
	Single issuer trust preferred securities	41,936			83			(2,637		)	39,382			—			—			39,382
	Corporate debt securities	107,132			4,068			—			111,200			—			—			111,200
	Equity securities - financial institutions	—			—			—			—			—			—			—
	Total available-for-sale	$	2,853,070		$	48,595		$	(27,779	)	$	2,873,886		$	—		$	—		$	2,873,886
	Held-to-maturity:
	Agency CMO	$	411,128		$	—		$	—		$	411,128		$	7,374		$	(1,409	)	$	417,093
	Agency MBS	2,181,225			—			—			2,181,225			52,799			(23,068		)	2,210,956
	Agency CMBS	377,382			—			—			377,382			650			(622		)	377,410
	Municipal bonds and notes	377,074			—			—			377,074			15,332			(38		)	392,368
	CMBS	288,692			—			—			288,692			8,833			(2,122		)	295,403
	Private Label MBS	6,478			—			—			6,478			117			—			6,595
	Total held-to-maturity	$	3,641,979		$	—		$	—		$	3,641,979		$	85,105		$	(27,259	)	$	3,699,825
	-1	Amortized cost is net of $2.8 million of other-than-temporary impairments at September 30, 2014.
		At December 31, 2013
					Recognized in OCI									Not Recognized in OCI
	(In thousands)	Amortized			Gross			Gross			Carrying			Gross			Gross			Fair Value
		Cost			Unrealized			Unrealized			Value			Unrealized			Unrealized
					Gains			Losses						Gains			Losses
	Available-for-sale:
	U.S. Treasury Bills	$	325		$	—		$	—		$	325		$	—		$	—		$	325
	Agency CMO	794,397			14,383			(1,868		)	806,912			—			—			806,912
	Agency MBS	1,265,276			9,124			(47,698		)	1,226,702			—			—			1,226,702
	Agency CMBS	71,759			—			(782		)	70,977			—			—			70,977
	CMBS	436,872			28,398			(996		)	464,274			—			—			464,274
	CLO (1)	357,326			315			—			357,641			—			—			357,641
	Pooled trust preferred securities (2)	31,900			—			(3,410		)	28,490			—			—			28,490
	Single issuer trust preferred securities	41,807			—			(6,872		)	34,935			—			—			34,935
	Corporate debt securities	108,936			4,155			—			113,091			—			—			113,091
	Equity securities - financial institutions (3)	2,314			1,270			—			3,584			—			—			3,584
	Total available-for-sale	$	3,110,912		$	57,645		$	(61,626	)	$	3,106,931		$	—		$	—		$	3,106,931
	Held-to-maturity:
	Agency CMO	$	365,081		$	—		$	—		$	365,081		$	10,135		$	(1,009	)	$	374,207
	Agency MBS	2,130,685			—			—			2,130,685			43,315			(53,188		)	2,120,812
	Agency CMBS	115,995			—			—			115,995			44			(818		)	115,221
	Municipal bonds and notes	448,405			—			—			448,405			11,104			(1,228		)	458,281
	CMBS	290,057			—			—			290,057			8,635			(4,975		)	293,717
	Private Label MBS	8,498			—			—			8,498			176			—			8,674
	Total held-to-maturity	$	3,358,721		$	—		$	—		$	3,358,721		$	73,409		$	(61,218	)	$	3,370,912
	-1	Amortized cost is net of $2.6 million of other-than-temporary impairments at December 31, 2013.
	-2	Amortized cost is net of $14.0 million of other-than-temporary impairments at December 31, 2013.
	-3	Amortized cost is net of $20.4 million of other-than-temporary impairments at December 31, 2013.
Summary of Debt Securities by Contractual Maturity	'
	The amortized cost and fair value of debt securities at September 30, 2014, by contractual maturity, are set forth below:
		Available-for-Sale							Held-to-Maturity
	(In thousands)	Amortized			Fair				Amortized			Fair
		Cost			Value				Cost			Value
	Due in one year or less	$	15,518		$	15,546			$	15		$	15
	Due after one year through five years	107,131			111,200				70,092			73,095
	Due after five through ten years	260,350			260,884				67,799			70,457
	Due after ten years	2,470,071			2,486,256				3,504,073			3,556,258
	Total debt securities	$	2,853,070		$	2,873,886			$	3,641,979		$	3,699,825
Summary of Gross Unrealized Losses not Considered OTTI	'
	The following tables provide information on the gross unrealized losses and fair value of the Company’s investment securities with unrealized losses that are not deemed to be other-than-temporarily impaired, aggregated by investment security type and length of time that individual investment securities have been in a continuous unrealized loss position:
		At September 30, 2014
		Less Than Twelve Months							Twelve Months or Longer							Total
	(Dollars in thousands)	Fair			Unrealized				Fair			Unrealized				# of	Fair			Unrealized
		Value			Losses				Value			Losses				Holdings	Value			Losses
	Available-for-sale:
	Agency CMO	$	82,646		$	(278	)		$	35,915		$	(779	)		10	$	118,561		$	(1,057	)
	Agency MBS	55,408			(262		)		665,932			(23,277		)		73	721,340			(23,539		)
	Agency CMBS	36,325			(88		)		44,057			(261		)		4	80,382			(349		)
	CMBS	15,000			(41		)		9,390			(14		)		3	24,390			(55		)
	CLO	31,858			(142		)		—			—				2	31,858			(142		)
	Pooled trust preferred securities	—			—				—			—				—	—			—
	Single issuer trust preferred securities	—			—				35,120			(2,637		)		7	35,120			(2,637		)
	Total available-for-sale in an unrealized loss position	$	221,237		$	(811	)		$	790,414		$	(26,968	)		99	$	1,011,651		$	(27,779	)
	Held-to-maturity:
	Agency CMO	$	111,069		$	(798	)		$	25,943		$	(611	)		10	$	137,012		$	(1,409	)
	Agency MBS	258,608			(1,161		)		671,769			(21,907		)		64	930,377			(23,068		)
	Agency CMBS	196,139			(622		)		—			—				9	196,139			(622		)
	Municipal bonds and notes	4,311			(6		)		3,075			(32		)		14	7,386			(38		)
	CMBS	5,494			(10		)		73,167			(2,112		)		8	78,661			(2,122		)
	Total held-to-maturity in an unrealized loss position	$	575,621		$	(2,597	)		$	773,954		$	(24,662	)		105	$	1,349,575		$	(27,259	)
		At December 31, 2013
		Less Than Twelve Months							Twelve Months or Longer							Total
	(Dollars in thousands)	Fair			Unrealized				Fair			Unrealized				# of	Fair			Unrealized
		Value			Losses				Value			Losses				Holdings	Value			Losses
	Available-for-sale:
	Agency CMO	$	149,894		$	(1,713	)		$	9,011		$	(155	)		15	$	158,905		$	(1,868	)
	Agency MBS	616,286			(29,537		)		279,680			(18,161		)		88	895,966			(47,698		)
	Agency CMBS	70,977			(782		)		—			—				3	70,977			(782		)
	CMBS	52,340			(996		)		—			—				7	52,340			(996		)
	CLO	—			—				—			—				—	—			—
	Pooled trust preferred securities	—			—				11,141			(3,410		)		2	11,141			(3,410		)
	Single issuer trust preferred securities	3,777			(381		)		31,158			(6,491		)		8	34,935			(6,872		)
	Total available-for-sale in an unrealized loss position	$	893,274		$	(33,409	)		$	330,990		$	(28,217	)		123	$	1,224,264		$	(61,626	)
	Held-to-maturity:
	Agency CMO	$	53,789		$	(1,009	)		$	—		$	—			4	$	53,789		$	(1,009	)
	Agency MBS	1,045,693			(42,181		)		170,780			(11,007		)		94	1,216,473			(53,188		)
	Agency CMBS	90,218			(818		)		—			—				4	90,218			(818		)
	Municipal bonds and notes	46,587			(1,193		)		2,166			(35		)		51	48,753			(1,228		)
	CMBS	106,527			(4,059		)		14,832			(916		)		11	121,359			(4,975		)
	Total held-to-maturity in an unrealized loss position	$	1,342,814		$	(49,260	)		$	187,778		$	(11,958	)		164	$	1,530,592		$	(61,218	)
Other than Temporary Impairment, Credit Losses Recognized in Earnings	'
	The following is a roll forward of the amount of OTTI related to debt securities:
		Three months ended September 30,								Nine months ended September 30,
	(In thousands)	2014				2013				2014				2013
	Balance of OTTI, beginning of period	$	9,738			$	10,460			$	16,633			$	10,460
	Reduction for securities sold, called	(7,026		)		(1,104		)		(14,082		)		(1,104		)
	Additions for OTTI not previously recognized	85				—				246				—
	Balance of OTTI, end of period	$	2,797			$	9,356			$	2,797			$	9,356
Summary of Sale Proceeds of Available for Sale Securities	'
	The following table summarizes proceeds from available-for-sale securities, the gross realized gains and losses from those sales, and the impact of the recognition of other-than-temporary impairments for the periods presented:
		Three months ended September 30,								Nine months ended September 30,
	(In thousands)	2014				2013				2014				2013
	Proceeds from sales(1)	$	16,380			$	7,740			$	38,075			$	44,261
	Gross realized gains	$	1,812			$	269			$	6,148			$	708
	Gross realized losses	(1,770		)		—				(1,770		)		—
	OTTI write-down	(85		)		—				(246		)		—
	Net realized (losses) gains from investment securities	$	(43	)		$	269			$	4,132			$	708
	-1	Proceeds from sales, for the three and nine months ended September 30, 2014, does not include $25.3 million of unsettled sales transactions at September 30, 2014. The gross realized gains and gross realized losses for the three and nine months ended September 30, 2014 reflect the unsettled sales transactions.

Loans_and_Leases_Loans_and_Lea

Loans and Leases Loans and Leases (Tables)	9 Months Ended
	Sep. 30, 2014
Loans and Leases Receivable Disclosure [Abstract]	'
Schedule of Participating Mortgage Loans	'
	The following tables summarize the recorded investment in loans and leases by portfolio segment:
		At September 30, 2014
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Total (2)
											Real Estate (1)			Financing
	Recorded Investment:
	Individually evaluated for impairment	$	144,355		$	51,503		$	41,329		$	100,560		$	1,759		$	339,506
	Collectively evaluated for impairment	3,321,447			2,538,505			3,602,406			3,261,898			488,391			13,212,647
	Recorded investment in loans and leases	3,465,802			2,590,008			3,643,735			3,362,458			490,150			13,552,153
	Less: Accrued interest	10,448			8,108			11,744			8,351			—			38,651
	Loans and leases	$	3,455,354		$	2,581,900		$	3,631,991		$	3,354,107		$	490,150		$	13,513,502
		At December 31, 2013
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Total (2)
											Real Estate (1)			Financing
	Recorded Investment:
	Individually evaluated for impairment	$	142,871		$	52,179		$	52,199		$	105,046		$	210		$	352,505
	Collectively evaluated for impairment	3,228,688			2,492,353			3,241,045			2,961,378			460,240			12,383,704
	Recorded investment in loans and leases	3,371,559			2,544,532			3,293,244			3,066,424			460,450			12,736,209
	Less: Accrued interest	10,134			7,844			10,393			8,062			—			36,433
	Loans and leases	$	3,361,425		$	2,536,688		$	3,282,851		$	3,058,362		$	460,450		$	12,699,776
	-1	Includes certain loans individually evaluated for impairment under the Company's loan policy that were deemed not to be impaired at both September 30, 2014 and December 31, 2013.
	-2	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.
Past Due Financing Receivables	'
	The following tables summarize the aging of the recorded investment in loans and leases by portfolio class:
		At September 30, 2014
	(In thousands)	30-59 Days			60-89 Days			> 90 Days Past Due			Non-accrual			Total Past Due and Non-accrual			Current			Total Loans
		Past Due and			Past Due and			and Accruing												and Leases
		Accruing			Accruing
	Residential: (1)	$	9,906		$	6,295		$	—		$	68,402		$	84,603		$	3,381,199		$	3,465,802
	Consumer:
	Home equity (1)	9,498			7,068			—			38,959			55,525			2,429,571			2,485,096
	Other consumer	671			334			—			244			1,249			103,663			104,912
	Commercial:
	Commercial non-mortgage	8,402			450			795			12,454			22,101			2,972,897			2,994,998
	Asset-based	—			—			—			—			—			648,737			648,737
	Commercial real estate:
	Commercial real estate	991			670			488			14,443			16,592			3,131,467			3,148,059
	Commercial construction	—			—			—			3,919			3,919			210,480			214,399
	Equipment financing	241			192			—			1,659			2,092			488,058			490,150
	Total	$	29,709		$	15,009		$	1,283		$	140,080		$	186,081		$	13,366,072		$	13,552,153
	-1	A total of $17.6 million residential and consumer loans was reclassified from non-accrual to accrual status as a result of updated regulatory guidance issued in the first quarter of 2014.
		At December 31, 2013
	(In thousands)	30-59 Days			60-89 Days			> 90 Days Past Due			Non-accrual			Total Past Due and Non-accrual			Current			Total Loans
		Past Due and			Past Due and			and Accruing												and Leases
		Accruing			Accruing
	Residential:	$	11,721		$	6,839		$	—		$	81,520		$	100,080		$	3,271,479		$	3,371,559
	Consumer:
	Home equity	15,332			5,120			—			51,788			$	72,240		2,410,953			$	2,483,193
	Other consumer	462			193			—			140			795			60,543			61,338
	Commercial:
	Commercial non-mortgage	3,208			984			4,305			10,946			19,443			2,712,870			2,732,313
	Asset-based	—			—			—			—			—			560,931			560,931
	Commercial real estate:
	Commercial real estate	4,387			587			235			13,456			18,665			2,842,637			2,861,302
	Commercial construction	—			—			—			4,237			4,237			200,886			205,123
	Equipment financing	299			63			—			1,141			1,503			458,947			460,450
	Total	$	35,409		$	13,786		$	4,540		$	163,228		$	216,963		$	12,519,246		$	12,736,209
Activity In Allowance For Losses	'
	The following tables summarize the ALLL by portfolio segment:
		At or for the three months ended September 30, 2014
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
											Real Estate			Financing
	Allowance for loan and lease losses:
	Balance, beginning of period	$	19,054		$	33,867		$	51,632		$	34,144		$	5,539		$	10,632		$	154,868
	Provision (benefit) charged to expense	2,006			5,357			2,051			68			344			(326		)	9,500
	Losses charged off	(1,870		)	(6,329		)	(2,738		)	(139		)	(491		)	—			(11,567		)
	Recoveries	261			1,947			1,017			120			336			—			3,681
	Balance, end of period	$	19,451		$	34,842		$	51,962		$	34,193		$	5,728		$	10,306		$	156,482
	Individually evaluated for impairment	$	11,501		4,165			$	1,717		3,818			$	29		$	—		$	21,230
	Collectively evaluated for impairment	$	7,950		$	30,677		$	50,245		$	30,375		$	5,699		$	10,306		$	135,252
		At or for the three months ended September 30, 2013
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
											Real Estate			Financing
	Allowance for loan and lease losses:
	Balance, beginning of period	$	26,876		$	49,659		$	43,847		$	28,457		$	3,603		$	11,000		$	163,442
	Provision (benefit) charged to expense	1,075			(1,732		)	3,783			6,046			(672		)	—			8,500
	Losses charged off	(3,800		)	(5,827		)	(3,245		)	(4,069		)	(10		)	—			(16,951		)
	Recoveries	152			1,188			426			105			683			—			2,554
	Balance, end of period	$	24,303		$	43,288		$	44,811		$	30,539		$	3,604		$	11,000		$	157,545
	Individually evaluated for impairment	$	13,003		$	3,281		$	1,630		$	5,397		$	—		$	—		$	23,311
	Collectively evaluated for impairment	$	11,300		$	40,007		$	43,181		$	25,142		$	3,604		$	11,000		$	134,234
		At or for the nine months ended September 30, 2014
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
											Real Estate			Financing
	Allowance for loan and lease losses:
	Balance, beginning of period	$	20,580		$	39,551		$	47,706		$	29,883		$	3,912		$	10,941		$	152,573
	Provision (benefit) charged to expense	2,711			7,530			10,716			6,633			795			(635		)	27,750
	Losses charged off	(4,868		)	(16,501		)	(9,571		)	(2,991		)	(511		)	—			(34,442		)
	Recoveries	1,028			4,262			3,111			668			1,532			—			10,601
	Balance, end of period	$	19,451		$	34,842		$	51,962		$	34,193		$	5,728		$	10,306		$	156,482
	Individually evaluated for impairment	$	11,501		$	4,165		$	1,717		$	3,818		$	29		$	—		$	21,230
	Collectively evaluated for impairment	$	7,950		$	30,677		$	50,245		$	30,375		$	5,699		$	10,306		$	135,252
		At or for the nine months ended September 30, 2013
	(In thousands)	Residential			Consumer			Commercial			Commercial			Equipment			Unallocated			Total
											Real Estate			Financing
	Allowance for loan and lease losses:
	Balance, beginning of period	$	29,474		$	54,254		$	46,566		$	30,834		$	4,001		$	12,000		$	177,129
	Provision (benefit) charged to expense	2,835			7,328			8,902			9,146			(2,711		)	(1,000		)	24,500
	Losses charged off	(8,848		)	(23,565		)	(13,740		)	(10,339		)	(101		)	—			(56,593		)
	Recoveries	842			5,271			3,083			898			2,415			—			12,509
	Balance, end of period	$	24,303		$	43,288		$	44,811		$	30,539		$	3,604		$	11,000		$	157,545
	Individually evaluated for impairment	$	13,003		$	3,281		$	1,630		$	5,397		$	—		$	—		$	23,311
	Collectively evaluated for impairment	$	11,300		$	40,007		$	43,181		$	25,142		$	3,604		$	11,000		$	134,234
Impaired Loans	'
	The following tables summarize impaired loans and leases by portfolio class:
		At September 30, 2014
	(In thousands)	Unpaid			Total			Recorded			Recorded			Related
		Principal			Recorded			Investment			Investment			Valuation
		Balance			Investment			No Allowance			With Allowance			Allowance
	Residential:
	1-4 family	$	159,486		$	144,355		$	24,272		$	120,083		$	11,501
	Consumer:
	Home equity	60,717			51,503			26,885			24,618			4,165
	Commercial:
	Commercial non-mortgage	50,359			41,329			17,754			23,575			1,717
	Commercial real estate:
	Commercial real estate	90,230			88,209			42,743			45,466			3,786
	Commercial construction	9,438			8,230			7,517			713			32
	Equipment financing	2,258			1,759			1,114			645			29
	Totals:
	Residential	159,486			144,355			24,272			120,083			11,501
	Consumer	60,717			51,503			26,885			24,618			4,165
	Commercial	50,359			41,329			17,754			23,575			1,717
	Commercial real estate	99,668			96,439			50,260			46,179			3,818
	Equipment financing	2,258			1,759			1,114			645			29
	Total	$	372,488		$	335,385		$	120,285		$	215,100		$	21,230
		At December 31, 2013
	(In thousands)	Unpaid			Total			Recorded			Recorded			Related
		Principal			Recorded			Investment			Investment			Valuation
		Balance			Investment			No Allowance			With Allowance			Allowance
	Residential:
	1-4 family	$	158,361		$	142,871		$	23,988		$	118,883		$	10,534
	Consumer:
	Home equity	63,886			52,179			27,323			24,856			4,595
	Commercial:
	Commercial non-mortgage	59,279			52,199			23,138			29,061			1,878
	Commercial real estate:
	Commercial real estate	95,013			90,976			42,774			48,202			3,444
	Commercial construction	11,725			10,625			10,625			—			—
	Equipment financing	249			210			210			—			—
	Totals:
	Residential	158,361			142,871			23,988			118,883			10,534
	Consumer	63,886			52,179			27,323			24,856			4,595
	Commercial	59,279			52,199			23,138			29,061			1,878
	Commercial real estate	106,738			101,601			53,399			48,202			3,444
	Equipment financing	249			210			210			—			—
	Total	$	388,513		$	349,060		$	128,058		$	221,002		$	20,451
	The following table summarizes the average recorded investment and interest income recognized for impaired loans and leases by portfolio class:
		30-Sep-14			Three months ended September 30, 2014						Nine months ended September 30, 2014							30-Sep-13			Three months ended September 30, 2013					Nine months ended September 30, 2013
	(In thousands)	Average			Accrued			Cash Basis Interest Income			Accrued			Cash Basis Interest Income				Average			Accrued			Cash Basis Interest Income		Accrued		Cash Basis Interest Income
		Recorded			Interest						Interest							Recorded			Interest					Interest
		Investment			Income						Income							Investment			Income					Income
	Residential:
	1-4 family	$	143,613		$	1,144		$	305		$	3,482		$	912			$	145,240		$	1,015		$	520	$	3,098	$	1,476
	Consumer:
	Home equity	51,841			372			307			1,100			930				53,850			250			413		748		1,301
	Commercial:
	Commercial non-mortgage	46,764			617			—			1,787			—				65,808			794			—		2,187		—
	Commercial real estate:
	Commercial real estate	89,593			933			—			2,585			—				116,307			1,109			—		3,675		—
	Commercial construction	9,428			75			—			216			—				16,323			161			—		482		—
	Equipment financing	985			11			—			17			—				1,136			6			—		19		—
	Totals:
	Residential	143,613			1,144			305			3,482			912				145,240			1,015			520		3,098		1,476
	Consumer	51,841			372			307			1,100			930				53,850			250			413		748		1,301
	Commercial	46,764			617			—			1,787			—				65,808			794			—		2,187		—
	Commercial real estate	99,021			1,008			—			2,801			—				132,630			1,270			—		4,157		—
Equipment financing	985			11			—			17			—				1,136			6			—		19		—
Total	$	342,224		$	3,152		$	612		$	9,187		$	1,842			$	398,664		$	3,335		$	933	$	10,209	$	2,777
Financing Receivable Credit Quality Indicators	'
	The recorded investment in commercial, commercial real estate, and equipment financing TDRs segregated by risk rating exposure is as follows:
	(In thousands)	At September 30,				At December 31,
		2014				2013
	(1) - (6) Pass	$	37,861			$	55,973
	(7) Special Mention	18,268				—
	(8) Substandard	70,601				90,461
	(9) Doubtful	346				414
	(10) Loss	—				—
	Total	$	127,076			$	146,848
	The recorded investment in commercial and commercial real estate loans and equipment financing leases segregated by risk rating exposure is as follows:
		Commercial								Commercial Real Estate								Equipment Financing
	(In thousands)	At September 30,				At December 31,				At September 30,				At December 31,				At September 30,				At December 31,
		2014				2013				2014				2013				2014				2013
	(1) - (6) Pass	$	3,474,698			$	3,091,154			$	3,191,834			$	2,947,116			$	468,407			$	437,033
	(7) Special Mention	63,830				87,451				61,354				20,901				2,080				7,979
	(8) Substandard	105,008				114,199				108,762				97,822				19,663				15,438
	(9) Doubtful	199				440				508				585				—				—
	(10) Loss	—				—				—				—				—				—
	Total	$	3,643,735			$	3,293,244			$	3,362,458			$	3,066,424			$	490,150			$	460,450
Troubled Debt Restructurings on Financing Receivables	'
	Troubled Debt Restructurings. The following table summarizes information for TDRs:
	(Dollars in thousands)	At September 30,				At December 31,
		2014				2013
	Recorded investment of TDRs:
	Accrual status (1)	$	236,128			$	238,926
	Non-accrual status (1)	87,003				102,972
	Total recorded investment of TDRs	$	323,131			$	341,898
	Accruing TDRs performing under modified terms more than one year	68.4		%		58.2		%
	Specific reserves for TDRs included in the balance of allowance for loan and lease losses	$	20,745			$	20,360
	Additional funds committed to borrowers in TDR status	495				1,262
	-1	A total of $17.6 million in residential and consumer loans was reclassified from non-accrual to accrual status in the nine months ended September 30, 2014 as a result of updated regulatory guidance issued in the first quarter of 2014.
	For the three and nine months ended September 30, 2014 and 2013, Webster charged off $2.1 million and $10.3 million and $3.2 million and $17.3 million, respectively, for the portion of TDRs deemed to be uncollectible.
	TDRs may be modified by means of extended maturity, below market adjusted interest rates, a combination of rate and maturity, or other means, including covenant modifications, forbearance, loans discharged under Chapter 7 bankruptcy, or other concessions.
	The following table provides information on how loans and leases were modified as TDRs:
		Three months ended September 30,											Nine months ended September 30,
		2014					2013						2014					2013
	Type of concession	Number of		Post-			Number of		Post-				Number of		Post-			Number of		Post-
		Loans and		Modification			Loans and		Modification				Loans and		Modification			Loans and		Modification
		Leases		Recorded			Leases		Recorded				Leases		Recorded			Leases		Recorded
	(Dollars in thousands)			Investment(1)					Investment(1)						Investment(1)					Investment(1)
	Residential:
	Extended Maturity	10		$	1,383		10		$	1,898			24		$	3,191		22		$	4,418
	Adjusted Interest rates	1		103			1		654				3		448			6		1,888
	Combination Rate and Maturity	2		275			8		1,142				16		3,522			38		7,213
	Other	32		7,600			5		1,177				47		10,433			30		5,611
	Consumer:
	Extended Maturity	4		143			10		307				18		911			20		961
	Adjusted Interest rates	—		—			—		—				1		51			4		154
	Combination Rate and Maturity	1		110			3		164				6		412			13		1,381
	Other	34		1,750			28		811				73		3,717			78		3,197
	Commercial:
	Extended Maturity	—		—			—		—				4		356			2		7,520
	Adjusted Interest rates	—		—			—		—				1		25			—		—
	Combination Rate and Maturity	5		342			12		353				18		974			19		982
	Other	2		101			2		4,568				5		6,647			3		4,607
	Commercial real estate:
	Extended Maturity	—		—			—		—				—		—			3		227
	Combination Rate and Maturity	—		—			2		340				—		—			4		12,015
	Equipment Financing
	Extended Maturity	1		492			—		—				1		492			—		—
	TOTAL TDRs	92		$	12,299		81		$	11,414			217		$	31,179		242		$	50,174
	(1) Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs as a result of the restructurings was not significant.
	The Company’s loan and lease portfolio at September 30, 2014 included loans with an A Note/B Note structure. The loans were restructured into A Note/B Note structures as a result of evaluating the cash flow of the borrowers to support repayment. Webster immediately charged off the balance of B Notes. The restructuring agreements specify a market interest rate equal to that which would be provided to a borrower with similar credit at the time of restructuring.
	The following table provides information on loans and leases modified as TDRs within the previous 12 months and for which there was a payment default during the periods presented:
		Three months ended September 30,										Nine months ended September 30,
		2014					2013					2014					2013
	(Dollars in thousands)	Number of	Recorded				Number of	Recorded				Number of	Recorded				Number of	Recorded
		Loans and	Investment				Loans and	Investment				Loans and	Investment				Loans and	Investment
		Leases					Leases					Leases					Leases
	Residential:
	1-4 family	3	$	196			8	$	1,116			3	$	196			12	$	1,814
	Consumer:
	Home equity	2	22				3	53				4	48				7	343
	Commercial real estate:
	Commercial real estate	—	—				1	500				—	—				1	500
	Total	5	$	218			12	$	1,669			7	$	244			20	$	2,657

Transfers_of_Financial_Assets_1

Transfers of Financial Assets and Mortgage Servicing Assets (Tables)	9 Months Ended
	Sep. 30, 2014
Transfers and Servicing [Abstract]	'
Schedule Of Reserve For Loan Repurchases Table	'
	The following table provides a summary of activity in the reserve for loan repurchases:
		Three months ended September 30,					Nine months ended September 30,
	(In thousands)	2014		2013			2014			2013
	Beginning balance	$	1,575	$	2,648		$	2,254		$	2,617
	Provision (benefit)	132		447			(391		)	1,462
	Loss on repurchased loans and settlements	—		(586		)	(156		)	(1,570		)
	Ending balance	$	1,707	$	2,509		$	1,707		$	2,509
Schedule of Loan Sale Activity	'
	The following table provides detail of activity related to loan sales:
		Three months ended September 30,					Nine months ended September 30,
	(In thousands)	2014		2013			2014			2013
	Residential mortgage loans:
	Proceeds from the sale of loans held for sale	$	85,311	$	199,903		$	207,530		$	657,541
	Net gain on sale included as mortgage banking activities	1,805		665			3,093			13,900
	Loans sold with servicing rights retained	78,848		192,283			193,781			622,550
	Commercial loans:
	Proceeds from the sale of loans held for sale	—		—			—			12,685
	Net loss on sale included as mortgage banking activities	—		—			—			(316		)

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill And Other Intangible Assets, Net Of Accumulated Amortization	'
	The following table presents the carrying value for goodwill allocated to the segments:
	(In thousands)	At September 30, 2014			At December 31, 2013
	Segment:
	Community Banking	$	516,560		$	516,560
	Other	13,327			13,327
	Goodwill	$	529,887		$	529,887
Schedule of Finite-Lived Intangible Assets	'
	The gross carrying amount and accumulated amortization of other intangible assets (core deposits) allocated to the business segments are as follows:
		At September 30, 2014							At December 31, 2013
	(In thousands)	Gross Carrying		Accumulated			Net Carrying		Gross Carrying		Accumulated			Net Carrying
		Amount		Amortization			Amount		Amount		Amortization			Amount
	Community Banking	$	49,420	$	(46,338	)	$	3,082	$	49,420	$	(44,069	)	$	5,351
Schedule Of Expected Amortization Expense, Next Four Years	'
	(In thousands)
	Years ending December 31:
	Remainder of 2014	$	415
	2015	1,524
	2016	1,143

Deposits_Tables

Deposits (Tables)	9 Months Ended
	Sep. 30, 2014
Banking and Thrift [Abstract]	'
Summary Of Deposits	'
	A summary of deposits by type follows:
	(In thousands)	At September 30,		At December 31,
		2014		2013
	Non-interest-bearing:
	Demand	$	3,256,741	$	3,128,152
	Interest-bearing:
	Checking	2,105,481		1,934,291
	Health savings accounts	1,765,671		1,533,310
	Money market	2,239,106		2,167,593
	Savings	3,877,673		3,863,930
	Time deposits	2,302,246		2,227,144
	Total interest-bearing	12,290,177		11,726,268
	Total deposits	$	15,546,918	$	14,854,420
	Demand deposit overdrafts reclassified as loan balances	$	1,791	$	1,455
Scheduled Maturities Of Time Deposits	'
	At September 30, 2014, the scheduled maturities of time deposits are as follows:
	(In thousands)	Years ending December 31:
	2014	$	357,663
	2015	1,041,544
	2016	305,677
	2017	120,685
	2018	149,111
	Thereafter	327,566
	Time deposits	$	2,302,246

Securities_Sold_Under_Agreemen1

Securities Sold Under Agreements to Repurchase and Other Borrowings (Tables)	9 Months Ended
	Sep. 30, 2014
Securities Sold Under Agreements to Repurchase and Other Short-term Borrowings [Abstract]	'
Summary Of Securities Sold Under Agreements To Repurchase And Other Borrowings	'
	The following table summarizes securities sold under agreements to repurchase and other borrowings:
	(In thousands)	At September 30,		At December 31,
		2014		2013
	Securities sold under agreements to repurchase:
	Original maturity of one year or less	$	398,975	$	359,662
	Original maturity of greater than one year, non-callable	550,000		550,000
	Callable at the option of the counterparty (1)	—		100,000
		948,975		1,009,662
	Other borrowings:
	Federal funds purchased	288,000		322,000
	Securities sold under agreements to repurchase and other borrowings	$	1,236,975	$	1,331,662
	-1	There were $100 million of securities sold under agreements to repurchase that had callable options for June 23, 2014 and were classified as callable at the option of the counterparty at December 31, 2013. The callable options were not exercised as of the call date and were reclassified as original maturity of greater than one year, non-callable during the quarter ended September 30, 2014.

Federal_Home_Loan_Bank_Advance1

Federal Home Loan Bank Advances (Tables)	9 Months Ended
	Sep. 30, 2014
Federal Home Loan Banks [Abstract]	'
Summary Of Advances Payable To The Federal Home Loan Bank	'
	The following table summarizes Federal Home Loan Bank advances:
		At September 30, 2014				At December 31, 2013
	(Dollars in thousands)	Total		Weighted-		Total		Weighted-
		Outstanding		Average Contractual Coupon Rate		Outstanding		Average Contractual Coupon Rate
	FHLB advances maturing:
	Within 1 year	$	1,775,000	0.2	%	$	1,550,000	0.25	%
	After 1 but within 2 years	145,934		1.8		—		—
	After 2 but within 3 years	—		—		145,934		1.8
	After 3 but within 4 years	100,500		1.49		500		5.66
	After 4 but within 5 years	108,731		1.33		200,000		1.36
	After 5 years	159,996		1.25		155,926		1.25
		2,290,161		0.48	%	2,052,360		0.54	%
	Unamortized premiums	43				61
	Federal Home Loan Bank advances	$	2,290,204			$	2,052,421

LongTerm_Debt_Tables

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Schedule Of Long-Term Debt	'
	The following table summarizes long-term debt:
	(Dollars in thousands)		At September 30,			At December 31,
			2014			2013
	4.38%	senior fixed-rate notes due 2024 (1)	$	150,000		$	—
	5.13%	senior fixed-rate notes due 2014	—			150,000
	Junior subordinated debt Webster Statutory Trust I floating-rate notes due 2033 (2)		77,320			77,320
	Total notes and subordinated debt		227,320			227,320
	Unamortized discount, net (3)		(1,112		)	(21		)
	Hedge accounting adjustments (3)		—			1,066
	Long-term debt		$	226,208		$	228,365
	-1	On February 11, 2014, Webster completed an underwritten public offering of $150.0 million aggregate principal amount of 4.375% senior notes maturing February 15, 2024. Webster received net proceeds of $148.0 million from the public offering
	-2	The interest rate on Webster Statutory Trust I floating-rate notes, which varies quarterly based on 3-month LIBOR plus 2.95%, was 3.185% at September 30, 2014 and 3.194% at December 31, 2013
	-3	Related to senior fixed-rate notes due 2024 at September 30, 2014 and senior fixed-rate notes due 2014 at December 31, 2013

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Schedule of Other Comprehensive Income (Loss)	'
	The following tables summarize the changes in accumulated other comprehensive loss by component:
		Three months ended September 30, 2014
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	21,256		$	(24,450	)	$	(26,801	)	$	(29,995	)
	Other comprehensive (loss) income before reclassifications	(8,133		)	493			437			(7,203		)
	Amounts reclassified from accumulated other comprehensive (loss) income	36			1,180			63			1,279
	Net current-period other comprehensive (loss) income, net of tax	(8,097		)	1,673			500			(5,924		)
	Ending balance	$	13,159		$	(22,777	)	$	(26,301	)	$	(35,919	)
		Three months ended September 30, 2013
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	2,729		$	(22,872	)	$	(44,996	)	$	(65,139	)
	Other comprehensive income (loss) before reclassifications	5,330			(1,413		)	528			4,445
	Amounts reclassified from accumulated other comprehensive income (loss)	(173		)	1,400			526			1,753
	Net current-period other comprehensive income (loss), net of tax	5,157			(13		)	1,054			6,198
	Ending balance	$	7,886		$	(22,885	)	$	(43,942	)	$	(58,941	)
		Nine months ended September 30, 2014
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	(2,617	)	$	(18,206	)	$	(27,726	)	$	(48,549	)
	Other comprehensive income (loss) before reclassifications	18,420			(8,534		)	1,372			11,258
	Amounts reclassified from accumulated other comprehensive income (loss)	(2,644		)	3,963			53			1,372
	Net current-period other comprehensive income (loss), net of tax	15,776			(4,571		)	1,425			12,630
	Ending balance	$	13,159		$	(22,777	)	$	(26,301	)	$	(35,919	)
		Nine months ended September 30, 2013
	(In thousands)	Available For Sale and Transferred Securities			Derivative Instruments			Defined Benefit Pension and Postretirement Benefit Plans			Total
	Beginning balance	$	42,741		$	(27,902	)	$	(47,105	)	$	(32,266	)
	Other comprehensive (loss) income before reclassifications	(34,400		)	467			1,584			(32,349		)
	Amounts reclassified from accumulated other comprehensive (loss) income	(455		)	4,550			1,579			5,674
	Net current-period other comprehensive (loss) income, net of tax	(34,855		)	5,017			3,163			(26,675		)
	Ending balance	$	7,886		$	(22,885	)	$	(43,942	)	$	(58,941	)
Schedule of Accumulated Other Comprehensive Income (Loss)	'
	The following tables summarize the reclassifications out of accumulated other comprehensive loss:
		Three months ended September 30,
		2014			2013
	Accumulated Other Comprehensive Loss Components	Amount Reclassified From Accumulated Other Comprehensive Loss			Amount Reclassified From Accumulated Other Comprehensive Loss			Associated Line Item in the Condensed Consolidated Statements Of Income
	(In thousands)
	Available-for-sale and transferred securities:
	Unrealized gains (losses) on investment securities	$	42		$	269		Net gain on sale of investment securities
	Unrealized gains (losses) on investment securities	(85		)	—			Impairment loss recognized in earnings
	Tax benefit (expense)	7			(96		)	Income tax expense
	Net of tax	$	(36	)	$	173
	Derivative instruments:
	Cash flow hedges	$	(1,853	)	$	(2,182	)	Total interest expense
	Tax benefit	673			782			Income tax expense
	Net of tax	$	(1,180	)	$	(1,400	)
	Defined benefit pension and postretirement benefit plans:
	Amortization of net loss	$	(80	)	$	(803	)	Compensation and benefits
	Prior service costs	(19		)	(18		)	Compensation and benefits
	Tax benefit	36			295			Income tax expense
	Net of tax	$	(63	)	$	(526	)
		Nine months ended September 30,
		2014			2013
	Accumulated Other Comprehensive Loss Components	Amount Reclassified From Accumulated Other Comprehensive Loss			Amount Reclassified From Accumulated Other Comprehensive Loss			Associated Line Item in the Condensed Consolidated Statements Of Income
	(In thousands)
	Available-for-sale and transferred securities:
	Unrealized gains (losses) on investment securities	$	4,378		$	708		Net gain on sale of investment securities
	Unrealized gains (losses) on investment securities	(246		)	—			Impairment loss recognized in earnings
	Tax expense	(1,488		)	(253		)	Income tax expense
	Net of tax	$	2,644		$	455
	Derivative instruments:
	Cash flow hedges	$	(6,189	)	$	(7,090	)	Total interest expense
	Tax benefit	2,226			2,540			Income tax expense
	Net of tax	$	(3,963	)	$	(4,550	)
	Defined benefit pension and postretirement benefit plans:
	Amortization of net loss	$	(28	)	$	(2,407	)	Compensation and benefits
	Prior service costs	(55		)	(54		)	Compensation and benefits
	Tax benefit	30			882			Income tax expense
	Net of tax	$	(53	)	$	(1,579	)

Regulatory_Matters_Tables

Regulatory Matters (Tables)	9 Months Ended
	Sep. 30, 2014
Regulatory Matters Disclosure [Abstract]	'
Information On The Capital Ratios	'
	The following table provides information on the capital ratios for Webster Financial Corporation and Webster Bank, N.A.:
		Capital				Capital Requirements
		Actual				Minimum				Well Capitalized
	(Dollars in thousands)	Amount		Ratio		Amount		Ratio		Amount		Ratio
	At September 30, 2014
	Webster Financial Corporation
	Total risk-based capital	$	2,060,208	14.2	%	$	1,163,206	8	%	$	1,454,008	10	%
	Tier 1 capital	1,898,704		13.1		581,603		4		872,405		6
	Tier 1 leverage capital	1,898,704		9		840,727		4		1,050,909		5
	Webster Bank, N.A.
	Total risk-based capital	$	1,901,130	13.1	%	$	1,161,080	8	%	$	1,451,350	10	%
	Tier 1 capital	1,739,626		12		580,540		4		870,810		6
	Tier 1 leverage capital	1,739,626		8.3		839,728		4		1,049,660		5
	At December 31, 2013
	Webster Financial Corporation
	Total risk-based capital	$	1,965,171	14.2	%	$	1,106,203	8	%	$	1,382,754	10	%
	Tier 1 capital	1,807,642		13.1		553,101		4		829,652		6
	Tier 1 leverage capital	1,807,642		9		801,535		4		1,001,919		5
	Webster Bank, N.A.
	Total risk-based capital	$	1,815,423	13.2	%	$	1,104,200	8	%	$	1,380,250	10	%
	Tier 1 capital	1,658,466		12		552,100		4		828,150		6
	Tier 1 leverage capital	1,658,466		8.3		800,063		4		1,000,079		5

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share Basic And Diluted	'
	The calculation of basic and diluted earnings per common share follows:
		Three months ended September 30,				Nine months ended September 30,
	(In thousands, except per share data)	2014		2013		2014		2013
	Earnings for basic and diluted earnings per common share:
	Net income available to common shareholders	$	47,819	$	44,666	$	140,820	$	127,631
	Less: Earnings allocated to participating securities	171		162		530		497
	Net income allocated to common shareholders	$	47,648	$	44,504	$	140,290	$	127,134
	Shares:
	Weighted-average common shares outstanding - basic	89,888		89,759		89,850		88,318
	Effect of dilutive securities:
	Stock options and restricted stock	464		451		471		406
	Warrants - Series A1 and A2	—		—		—		1,300
	Warrants - other	262		213		270		169
	Weighted-average common shares outstanding - diluted	90,614		90,423		90,591		90,193
	Earnings per common share:
	Basic	$	0.53	$	0.5	$	1.56	$	1.44
	Diluted	0.53		0.49		1.55		1.41

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Schedule of Notional Amounts of Outstanding Derivative Positions	'
	The table below presents information for Webster's forward-settle interest rate swaps outstanding at September 30, 2014:
	(Dollars in thousands)
	Number of Instruments	Total Notional Amount			Trade Date	Effective Date	Maturity Date	Debt Issuance Expected
	1	$	25,000		Sep-13	Jun-14	Jun-19	At or before March 2015
	4	$	100,000		October 2013, November 2013	October 2014, November 2014	October 2019, November 2019	At or before May 2015
	2	$	50,000		Jan-14	Jan-15	Jan-20	October 2014 - July 2015
	2	$	50,000		April 2014, May 2014	Jun-15	Jun-20	March 2015 - December 2015
	Webster uses interest rate swaps and caps to protect the Company from exposure to variability in cash flows relating to interest payments on floating-rate funding instruments. The swaps and caps are structured to offset fluctuations in interest rates on floating-rate debt during the life of the funding instrument.
	The table below presents information for Webster's interest rate swaps and caps outstanding at September 30, 2014:
	(Dollars in thousands)
	Number of Instruments	Total Notional Amount			Instrument Type	Trade Date	Index Rate	Hedged Debt	Maturity Date
	6	$	150,000		Cap	April 2013, January 2014, February 2014, April 2014	3.0% strike	$150 million 3-month LIBOR indexed floating-rate FHLB advance	Dec-21
	4	$	100,000		Swap	June 2014, July 2014	1-month LIBOR	$100 million 28 day rolling FHLB advance for a 5 year term	July 2019, August 2019, September 2019
Fair Value Of Derivative Financial Instruments Designated As Cash Flow Hedges	'
	The table below presents the notional amount and fair value for Webster’s interest rate derivatives designated as cash flow hedges as well as their classification in the accompanying Condensed Consolidated Balance Sheets:
			At September 30, 2014								At December 31, 2013
	(Dollars in thousands)	Balance Sheet	# of	Notional			Fair				# of	Notional			Fair
		Classification	Instruments	Amount			Value				Instruments	Amount			Value
	Forward-settle interest rate swap	Other assets	—	$	—		$	—			8	$	200,000		$	3,027
	Forward-settle interest rate swap	Other liabilities	9	225,000			(2,812		)		5	125,000			(622		)
	Interest rate swap	Other assets	4	100,000			263				—	—			—
	Interest rate cap	Other assets	6	150,000			6,094				2	50,000			3,554
Net Impact On Interest Expense Related To Cash Flow Hedges	'
	The increase/(reduction) to interest expense on borrowings related to cash flow hedges is presented below:
		Three months ended September 30,
		2014							2013
	(In thousands)	Interest			Amount Reclassified From AOCI				Interest			Amount Reclassified From AOCI
		Expense							Expense
	Interest rate swaps on FHLB advances	$	188		$	1,355			$	—		$	1,353
	Interest rate swaps on senior fixed-rate notes	—			76				—			—
	Interest rate swaps on junior subordinated debt	—			—				—			—
	Interest rate swaps on repurchase agreements	—			361				—			829
	Interest rate swaps on brokered certificates of deposit	—			61				—			—
	Net increase to interest expense on borrowings	$	188		$	1,853			$	—		$	2,182
		Nine months ended September 30,
		2014							2013
	(In thousands)	Interest			Amount Reclassified From AOCI				Interest			Amount Reclassified From AOCI
		Expense							Expense
	Interest rate swaps on FHLB advances	$	188		$	4,060			$	498		$	4,604
	Interest rate swaps on senior fixed-rate notes	—			191				—			—
	Interest rate swaps on junior subordinated debt	—			—				—			(3		)
	Interest rate swaps on repurchase agreements	—			1,864				—			2,489
	Interest rate swaps on brokered certificates of deposit	—			74				—			—
	Net increase to interest expense on borrowings	$	188		$	6,189			$	498		$	7,090
Net Impact On Interest Expense Related To Fair Value Hedges	'
	The reduction to interest expense on borrowings related to fair value hedges is presented below:
		Three months ended September 30,								Nine months ended September 30,
	(In thousands)	2014				2013				2014				2013
	Interest rate swaps on senior fixed-rate notes	$	—			$	(799	)		$	(1,066	)		$	(2,398	)
	Interest rate swaps on junior subordinated debt	—				—				—				(207		)
	Net reduction to interest expense on borrowings	$	—			$	(799	)		$	(1,066	)		$	(2,605	)
Interest Rate Swaps And Caps Not Designated For Hedge Accounting	'
	Webster had the following derivative positions that were not designated for hedge accounting:
			At September 30, 2014
								Fair Value
	(Dollars in thousands)	Balance Sheet	# of		Notional			Gain			Loss			Net
		Classification	Instruments		Amount
	Webster with customer position:
	Commercial loan interest rate derivatives	Other assets	196		$	1,245,748		$	35,207		$	—		$	35,207
	Commercial loan interest rate derivatives	Other liabilities	73		685,273			—			(5,534		)	(5,534		)
	Total customer position		269		$	1,931,021		$	35,207		$	(5,534	)	$	29,673
	Webster with counterparty position:
	Commercial loan interest rate derivatives	Other assets	84		$	605,806		$	4,019		$	(2,625	)	$	1,394
	Commercial loan interest rate derivatives	Other liabilities	179		1,325,151			5,828			(21,682		)	(15,854		)
	Futures contracts	Other liabilities	10		8,000,000			8			(450		)	(442		)
	Total counterparty position		273		$	9,930,957		$	9,855		$	(24,757	)	$	(14,902	)
			At December 31, 2013
								Fair Value
	(Dollars in thousands)	Balance Sheet	# of		Notional			Gain			Loss			Net
		Classification	Instruments		Amount
	Webster with customer position:
	Commercial loan interest rate derivatives	Other assets	159		$	915,272		$	29,004		$	—		$	29,004
	Commercial loan interest rate derivatives	Other liabilities	76		648,456			—			(11,175		)	(11,175		)
	Total customer position		235		$	1,563,728		$	29,004		$	(11,175	)	$	17,829
	Webster with counterparty position:
	Commercial loan interest rate derivatives	Other assets	111		$	914,044		$	8,944		$	(2,766	)	$	6,178
	Commercial loan interest rate derivatives	Other liabilities	118		649,623			8,118			(20,094		)	(11,976		)
	Futures contracts	Other liabilities	14		11,200,000			32			(259		)	(227		)
	Total counterparty position		243		$	12,763,667		$	17,094		$	(23,119	)	$	(6,025	)
Changes In Fair Value Of Non-Hedge Accounting Derivatives	'
	Webster reported the changes in the fair value of non-hedge accounting derivatives as a component of other non-interest income in the accompanying Condensed Consolidated Statements of Income as follows:
		Three months ended September 30,								Nine months ended September 30,
	(In thousands)	2014				2013				2014				2013
	Non-hedge derivatives, net	$	1,769			$	1,511			5,335				3,144
	Futures contracts	(299		)		(450		)		(585		)		(290		)
	Net increase to other non-interest income	$	1,470			$	1,061			$	4,750			$	2,854
Offsetting Assets and Liabilities	'
	The tables below present the financial assets and liabilities for non-customer derivative positions, including futures contracts, summarized by dealer counterparty or Derivative Clearing Organization ("DCO"):
		At September 30, 2014
		Notional Amount				Hedge Accounting Positions							Non-Hedge Accounting Positions						Total MTM(Loss) Gain			Cash Collateral Posted (Received)			Net Exposure (1)
	(In thousands)					MTM Gain			MTM Loss				MTM Gain			MTM Loss
	Dealer A	$	452,476			$	263		$	—			$	3,045		$	(7,455	)	$	(4,147	)	$	4,200		$	53
	Dealer B	327,019				2,031			—				1,933			(6,853		)	(2,889		)	3,160			271
	Dealer C	11,714				—			—				—			(908		)	(908		)	—			—
	Dealer D	318,886				1,016			—				2,219			(1,107		)	2,128			(2,200		)	—
	Dealer E	386,920				3,047			—				1,800			(1,518		)	3,329			(3,250		)	—
	Dealer F (2)	8,908,942				—			(2,812		)		858			(6,916		)	(8,870		)	21,595			12,725
	Total	$	10,405,957			$	6,357		$	(2,812	)		$	9,855		$	(24,757	)	$	(11,357	)	$	23,505
		At December 31, 2013
		Notional Amount				Hedge Accounting Positions							Non-Hedge Accounting Positions						Total MTM (Loss) Gain			Cash Collateral Posted (Received)			Net Exposure (1)
	(In thousands)					MTM Gain			MTM Loss				MTM Gain			MTM Loss
	Dealer A	$	387,258			$	730		$	—			$	4,643		$	(9,647	)	$	(4,274	)	$	4,300		$	26
	Dealer B	322,888				615			—				3,475			(9,100		)	(5,010		)	4,940			—
	Dealer C	14,477				—			—				—			(1,348		)	(1,348		)	—			—
	Dealer D	291,627				1,734			—				4,108			(592		)	5,250			(5,300		)	—
	Dealer E	372,771				2,290			(15		)		3,017			(1,743		)	3,549			(3,310		)	—
	Dealer F (2)	11,749,646				1,212			(607		)		1,819			(657		)	1,767			7,485			9,252
	Total	$	13,138,667			$	6,581		$	(622	)		$	17,062		$	(23,087	)	$	(66	)	$	8,115
	(1) Net positive exposure represents over-collateralized loss positions which can be the result of DCO initial margin requirements posted in compliance with the Dodd-Frank Wall Street Reform and Consumer Protection Act.
	(2) Dealer F represents Chicago Mercantile Exchange, our designated DCO.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis	'
	A summary of fair value for assets and liabilities measured at fair value on a recurring basis is as follows:
		At September 30, 2014
	(In thousands)	Total			Quoted Prices in			Significant Other			Significant
					Active Markets for			Observable  Inputs			Unobservable  Inputs
					Identical Assets			(Level 2)			(Level 3)
					(Level 1)
	Financial assets held at fair value:
	Available-for-sale investment securities:
	U.S. Treasury Bills	$	525		$	525		$	—		$	—
	Agency CMO	638,223			—			638,223			—
	Agency MBS	1,090,820			—			1,090,820			—
	Agency CMBS	80,383			—			80,383			—
	CMBS	532,842			—			532,842			—
	CLO	380,511			—			380,511			—
	Pooled trust preferred securities	—			—			—			—
	Single issuer trust preferred securities	39,382			—			39,382			—
	Corporate debt	111,200			—			111,200			—
	Equity securities	—			—			—			—
	Total available-for-sale investment securities	2,873,886			525			2,873,361			—
	Derivative instruments	43,039			8			43,031			—
	Mortgage banking derivatives	387			—			387			—
	Investments held in Rabbi Trust	5,841			5,841			—			—
	Alternative investments	477			—			—			477
	Total financial assets held at fair value	$	2,923,630		$	6,374		$	2,916,779		$	477
	Financial liabilities held at fair value:
	Derivative instruments	$	24,820		$	450		$	24,370		$	—
	Total financial liabilities held at fair value	$	24,820		$	450		$	24,370		$	—
		At December 31, 2013
	(In thousands)	Total			Quoted Prices in			Significant Other			Significant
					Active Markets for			Observable  Inputs			Unobservable  Inputs
					Identical Assets			(Level 2)			(Level 3)
					(Level 1)
	Financial assets held at fair value:
	Available-for-sale investment securities:
	U.S. Treasury Bills	$	325		$	325		$	—		$	—
	Agency CMO	806,912			—			806,912			—
	Agency MBS	1,226,702			—			1,226,702			—
	Agency CMBS	70,977			—			70,977			—
	CMBS	464,274			—			464,274			—
	CLO	357,641			—			357,641			—
	Pooled trust preferred securities	28,490			—			—			28,490
	Single issuer trust preferred securities	34,935			—			34,935			—
	Corporate debt	113,091			—			113,091			—
	Equity securities	3,584			3,309			275			—
	Total available-for-sale investment securities	3,106,931			3,634			3,074,807			28,490
	Derivative instruments	41,795			32			41,763			—
	Mortgage banking derivatives	540			—			540			—
	Investments held in Rabbi Trust	6,097			6,097			—			—
	Alternative investments	565			—			—			565
	Total financial assets held at fair value	$	3,155,928		$	9,763		$	3,117,110		$	29,055
	Financial liabilities held at fair value:
	Derivative instruments	$	24,038		$	259		$	23,779		$	—
	Total financial liabilities held at fair value	$	24,038		$	259		$	23,779		$	—
Schedule Of Quantitative Inputs And Assumptions For Items Categorized In Level 3 Of The Fair Value Hierarchy	'
	The following table presents the changes in Level 3 assets and liabilities that are measured at fair value on a recurring basis:
		Three months ended September 30,							Nine months ended September 30,
	(In thousands)	2014			2013				2014			2013
	Level 3, beginning of period	$	11,668		$	31,572			$	29,055		$	116,280
	Transfers out of Level 3 (1)	—			—				—			(248,844		)
	Change in unrealized loss included in other comprehensive income	3,216			7,194				3,410			14,194
	Unrealized loss included in net income	(29		)	(70		)		(261		)	(355		)
	Realized gain on sale of available for sale securities	(1,680		)	269				2,656			269
	Purchases/capital calls	173			—				173			159,412
	Sales/proceeds	(12,881		)	(7,740		)		(34,576		)	(7,740		)
	Accretion/amortization	10			26				62			214
	Calls/paydowns	—			(483		)		(42		)	(2,662		)
	Level 3, end of period	$	477		$	30,768			$	477		$	30,768
	-1	As of April 1, 2013, the CLO portfolio was transferred from Level 3 to Level 2 based on having more observable inputs in determining fair value. In prior quarters, the CLO portfolio was priced using average non-binding broker quotes. During the second quarter of 2013, the Company engaged a third-party pricing vendor to provide monthly fair value measurements. This methodology used is a combination of matrix pricing, observed market activity and metrics. Pricing inputs such as credit spreads are observable and market corroborated and, therefore, the CLO portfolio qualifies for Level 2 categorization. The market for CLO is an active market, and there is ample price transparency.
Schedule Of Valuation Methodology And Unobservable Inputs	'
	The table below presents the valuation methodology and unobservable inputs for Level 3 assets measured at fair value on a non-recurring basis at September 30, 2014:
	(Dollars in thousands)
	Asset	Fair Value			Valuation Methodology	Unobservable Inputs	Range of Inputs
	Impaired loans and leases	$	40,927		Real Estate Appraisals	Discount for appraisal type	2% - 15%
						Discount for costs to sell	0% - 8%
	Other real estate owned	$	831		Real Estate Appraisals	Discount for appraisal type	0% - 25%
						Discount for costs to sell	8%
	Mortgage servicing assets	$	29,213		Discounted cash flow	Constant prepayment rate	6.8% - 25.3%
						Discount rates	1.4% - 3.7%
Summary Of Estimated Fair Values Of Significant Financial Instruments	'
	The estimated fair values of selected financial instruments are as follows:
		At September 30, 2014								At December 31, 2013
	(In thousands)	Carrying				Fair Value				Carrying				Fair Value
		Amount								Amount
	Financial Assets
	Level 2 inputs:
	Held-to-maturity investment securities	$	3,641,979			$	3,699,825			$	3,358,721			$	3,370,912
	Loans held for sale	26,083				26,453				20,802				20,903
	Level 3 inputs:
	Loans and leases	13,357,020				13,377,939				12,547,203				12,515,714
	Mortgage servicing assets (1)	19,651				29,213				20,983				29,150
	Alternative investments	16,188				19,208				16,582				17,047
	Financial Liabilities
	Level 2 inputs:
	Deposit liabilities, other than time deposits	$	13,244,672			$	13,244,672			$	12,627,276			$	12,627,276
	Time deposits	2,302,246				2,317,764				2,227,144				2,250,141
	Securities sold under agreements to repurchase and other borrowings	1,236,975				1,257,595				1,331,662				1,365,427
	Federal Home Loan Bank advances (2)	2,290,204				2,301,591				2,052,421				2,063,312
	Long-term debt (3)	226,208				223,278				228,365				221,613
	-1	The carrying amount of mortgage servicing assets is net of $11 thousand and $0.2 million reserves at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.
	-2	The carrying amount of FHLB advances is net of $43 thousand and $61 thousand in hedge accounting adjustments and discounts at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.
	-3	The carrying amount of long-term debt is net of $1.1 million in discount at September 30, 2014 and $1.0 million in discount and hedge accounting adjustments, net at December 31, 2013. The estimated fair value does not include such adjustments.

Pension_and_Other_Postretireme1

Pension and Other Postretirement Benefits (Tables)	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Summary of Net Periodic Benefit Cost	'
	The following table summarizes the components of net periodic benefit cost:
		Three months ended September 30,
		Webster Pension						Webster SERP						Other Benefits
	(In thousands)	2014			2013			2014			2013			2014			2013
	Service cost	$	10		$	10		$	—		$	—		$	—		$	—
	Interest cost on projected benefit obligations	2,046			1,841			89			72			36			30
	Expected return on plan assets	(2,871		)	(2,779		)	—			—			—			—
	Amortization of prior service cost	—			—			—			—			18			18
	Recognized net loss	711			1,590			55			32			4			7
	Net periodic benefit cost (income)	$	(104	)	$	662		$	144		$	104		$	58		$	55
		Nine months ended September 30,
		Webster Pension						Webster SERP						Other Benefits
	(In thousands)	2014			2013			2014			2013			2014			2013
	Service cost	$	30		$	30		$	—		$	—		$	—		$	—
	Interest cost on benefit obligations	6,051			5,524			273			217			104			90
	Expected return on plan assets	(8,621		)	(8,336		)	—			—			—			—
	Amortization of prior service cost	—			—			—			—			55			54
	Recognized net loss	2,086			4,767			101			94			4			21
	Net periodic benefit cost (income)	$	(454	)	$	1,985		$	374		$	311		$	163		$	165
Schedule of Multiemployer Plans	'
	The following table sets forth contributions and funding status of the Fund:
	(In thousands)	Contributions by Webster  Bank							Contributions by Webster  Bank							Funded Status of Plan
		Three Months Ended September 30,							Nine Months Ended September 30,
	EIN/Pension Plan Number	2014			2013				2014			2013				As of July 1, 2013
	13-5645888/333	$	—		$	60			$	674		$	534			At least 80 percent

StockBased_Compensation_Plans_

Stock-Based Compensation Plans (Tables)	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Schedule of Allocation of Share-based Compensation Costs by Plan	'
	The following table provides a summary of stock-based compensation expense recognized in the accompanying Condensed Consolidated Statements of Income:
		Three months ended September 30,						Nine months ended September 30,
	(In thousands)	2014			2013			2014			2013
	Stock options	$	167		$	886		$	943		$	2,832
	Restricted stock	2,076			1,276			6,850			4,925
	Stock-based compensation	$	2,243		$	2,162		$	7,793		$	7,757
Schedule of Unrecognized Share-based Compensation Expense	'
	The following table provides a summary of unrecognized stock-based compensation expense:
		At September 30, 2014
	(Dollars in thousands)	Unrecognized Compensation Expense			Weighted-Average Period To Be Recognized
	Stock options	$	654		1.3 years
	Restricted stock	$	11,659		2.0 years
Schedule of Share-based Compensation, Activity	'
	The following table provides a summary of the activity under the Plans for the nine months ended September 30, 2014:
		Restricted Stock Awards Outstanding															Stock Options Outstanding
		Time-Based											Performance-Based
		Number of		Weighted-Average			Number of		Weighted-Average				Number of		Weighted-Average		Number of		Weighted-Average
		Shares		Grant Date			Units		Grant Date				Shares		Grant Date		Shares		Exercise Price
				Fair Value					Fair Value						Fair Value
	Outstanding, at January 1, 2014	267,119		$	22.96		1,705		$	22.75			138,450		$	24.43	2,325,797		$	26.97
	Granted	215,412		29.65			13,678		29.34				146,248		29.94		—		—
	Exercised options	—		—			—		—				—		—		(108,841	)	15.98
	Vested restricted stock awards (1)	(166,008	)	24.68			(9,685	)	28.18				(113,394	)	25.84		—		—
	Forfeited	(21,941	)	25.27			—		—				(16,909	)	26.47		(94,380	)	35.3
	Outstanding, at September 30, 2014	294,582		$	26.71		5,698		$	29.34			154,395		$	28.4	2,122,576		$	27.16
	Options exercisable, at September 30, 2014																1,814,294		$	27.83
	Options expected to vest, at September 30, 2014																294,667		$	23.24
	(1) Vested for purposes of recording compensation expense.

Segment_Reporting_Tables

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Operating Results And Total Assets Reportable Segments	'
	The following tables present the results for Webster’s business segments and incorporate the allocation of the provision for loan and lease losses and income tax expense to each of Webster’s business segments for the periods presented:
		Three months ended September 30, 2014
	(In thousands)	Commercial		Community Banking		Other		Segment Totals		Corporate and			Consolidated
		Banking								Reconciling			Total
	Net interest income (loss)	$	61,249	$	88,602	$	12,117	$	161,968	$	(4,598	)	$	157,370
	Provision (benefit) for loan and lease losses	3,340		6,159		26		9,525		(25		)	9,500
	Net interest income (loss) after provision for loan and lease losses	57,909		82,443		12,091		152,443		(4,573		)	147,870
	Non-interest income	8,861		27,307		9,471		45,639		5,270			50,909
	Non-interest expense	25,445		79,735		14,807		119,987		4,655			124,642
	Income (loss) before income tax expense	41,325		30,015		6,755		78,095		(3,958		)	74,137
	Income tax expense (benefit)	13,148		9,588		2,162		24,898		(1,219		)	23,679
	Net income (loss)	$	28,177	$	20,427	$	4,593	$	53,197	$	(2,739	)	$	50,458
		Three months ended September 30, 2013
	(In thousands)	Commercial		Community Banking		Other		Segment Totals		Corporate and			Consolidated
		Banking								Reconciling			Total
	Net interest income (loss)	$	56,430	$	87,949	$	10,733	$	155,112	$	(5,125	)	$	149,987
	Provision for loan and lease losses	7,032		3,570		22		10,624		(2,124		)	8,500
	Net interest income (loss) after provision for loan and lease losses	49,398		84,379		10,711		144,488		(3,001		)	141,487
	Non-interest income	8,818		25,387		8,083		42,288		3,969			46,257
	Non-interest expense	24,647		82,748		11,913		119,308		2,973			122,281
	Income (loss) before income tax expense	33,569		27,018		6,881		67,468		(2,005		)	65,463
	Income tax expense (benefit)	9,347		7,504		1,941		18,792		(634		)	18,158
	Net income (loss)	$	24,222	$	19,514	$	4,940	$	48,676	$	(1,371	)	$	47,305
		Nine months ended September 30, 2014
	(In thousands)	Commercial		Community Banking		Other		Segment		Corporate and			Consolidated
		Banking						Totals		Reconciling			Total
	Net interest income (loss)	$	175,058	$	263,893	$	35,192	$	474,143	$	(6,350	)	$	467,793
	Provision (benefit) for loan and lease losses	18,031		12,156		334		30,521		(2,771		)	27,750
	Net interest income (loss) after provision for loan and lease losses	157,027		251,737		34,858		443,622		(3,579		)	440,043
	Non-interest income	24,761		77,571		29,089		131,421		16,912			148,333
	Non-interest expense	76,579		241,314		43,050		360,943		10,901			371,844
	Income before income tax expense	105,209		87,994		20,897		214,100		2,432			216,532
	Income tax expense	32,940		27,551		6,543		67,034		761			67,795
	Net income	$	72,269	$	60,443	$	14,354	$	147,066	$	1,671		$	148,737
		Nine months ended September 30, 2013
	(In thousands)	Commercial		Community Banking		Other		Segment		Corporate and			Consolidated
		Banking						Totals		Reconciling			Total
	Net interest income (loss)	$	161,008	$	259,037	$	30,008	$	450,053	$	(7,209	)	$	442,844
	Provision (benefit) for loan and lease losses	11,449		15,816		72		27,337		(2,837		)	24,500
	Net interest income (loss) after provision for loan and lease losses	149,559		243,221		29,936		422,716		(4,372		)	418,344
	Non-interest income	20,537		87,654		24,579		132,770		14,016			146,786
	Non-interest expense	74,068		251,759		37,112		362,939		8,481			371,420
	Income before income tax expense	96,028		79,116		17,403		192,547		1,163			193,710
	Income tax expense	28,710		23,654		5,203		57,567		348			57,915
	Net income	$	67,318	$	55,462	$	12,200	$	134,980	$	815		$	135,795
		Total Assets
	(In thousands)	Commercial		Community Banking		Other		Segment Totals		Corporate and			Consolidated
		Banking								Reconciling			Total
	At September 30, 2014	$	6,251,726	$	8,062,212	$	391,280	$	14,705,218	$	7,121,664		$	21,826,882
	At December 31, 2013	$	5,682,129	$	7,809,343	$	365,863	$	13,857,335	$	6,995,664		$	20,852,999

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Outstanding Financial Instruments Contract Amounts Represent Credit Risk	'
	The following table summarizes outstanding contract amounts for off-balance sheet instruments that represent credit risk:
	(In thousands)	At September 30,		At December 31,
		2014		2013
	Unused commitments to extend credit	$	4,390,764	$	4,127,089
	Standby letters of credit	146,689		135,761
	Commercial letters of credit	26,025		13,621
	Total financial instruments with off-balance sheet risk	$	4,563,478	$	4,276,471
Reserve For Unfunded Credit Commitments	'
	The following table provides activity details for the Company’s reserve for unfunded credit commitments:
		Three months ended September 30,				Nine months ended
						September 30,
	(In thousands)	2014		2013		2014		2013
	Balance, beginning of period	$	4,749	$	4,593	$	4,384	$	5,662
	Provision (benefit)	273		64		638		(1,005		)
	Balance, end of period	$	5,022	$	4,657	$	5,022	$	4,657

Recovered_Sheet1

Summary Of Significant Accounting Policies (Narrative) (Detail)	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Line Items]	'
Number of grace period days to become non-accrual loans	'90 days
Term past due loans places on non-accrual status	'90 days
Number of grace period days to charge-off loans	'180 days
Minimum Period Discharged Bankruptcy Loan Post-Discharge Consecutive Payments	'6 months
Minimum period troubled debt restructurings placed on non-accrual status	'6 months
Minimum [Member]	'
Organization, Consolidation and Presentation of Financial Statements [Line Items]	'
Minimum Demonstrated Performance Period Troubled Debt Restructurings Returned To Accrual Status	'6 months
Maximum [Member]	'
Organization, Consolidation and Presentation of Financial Statements [Line Items]	'
Minimum Demonstrated Performance Period Troubled Debt Restructurings Returned To Accrual Status	'1 year

Investment_Securities_Summary_

Investment Securities (Summary Of Investment Securities) (Detail) (USD $)	Sep. 30, 2014		Jun. 30, 2014	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	$2,853,070		'	$3,110,912		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	48,595		'	57,645		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-27,779		'	-61,626		'	'	'
Fair Value	2,873,886		'	3,106,931		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	3,641,979		'	3,358,721		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	85,105		'	73,409		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	-27,259		'	-61,218		'	'	'
Held to Maturity, Fair Value - Total debt securities	3,699,825		'	3,370,912		'	'	'
Other than temporary impairment	2,797		9,738	16,633		9,356	10,460	10,460
U.S. Treasury Bills [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	525		'	325		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	0		'	0		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	0		'	0		'	'	'
Fair Value	525		'	325		'	'	'
Agency collateralized mortgage obligations (CMOs) [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	628,737		'	794,397		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	10,543		'	14,383		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-1,057		'	-1,868		'	'	'
Fair Value	638,223		'	806,912		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	411,128		'	365,081		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	7,374		'	10,135		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	-1,409		'	-1,009		'	'	'
Held to Maturity, Fair Value - Total debt securities	417,093		'	374,207		'	'	'
Agency mortgage-backed securities (MBS) [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	1,103,345		'	1,265,276		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	11,014		'	9,124		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-23,539		'	-47,698		'	'	'
Fair Value	1,090,820		'	1,226,702		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	2,181,225		'	2,130,685		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	52,799		'	43,315		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	-23,068		'	-53,188		'	'	'
Held to Maturity, Fair Value - Total debt securities	2,210,956		'	2,120,812		'	'	'
Agency commercial mortgage-backed securities (ACMBS) [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	80,732		'	71,759		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	0		'	0		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-349		'	-782		'	'	'
Fair Value	80,383		'	70,977		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	377,382		'	115,995		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	650		'	44		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	-622		'	-818		'	'	'
Held to Maturity, Fair Value - Total debt securities	377,410		'	115,221		'	'	'
Commercial mortgage-backed securities (CMBS) [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	510,922		'	436,872		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	21,975		'	28,398		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-55		'	-996		'	'	'
Fair Value	532,842		'	464,274		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	288,692		'	290,057		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	8,833		'	8,635		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	-2,122		'	-4,975		'	'	'
Held to Maturity, Fair Value - Total debt securities	295,403		'	293,717		'	'	'
Collateralized loan obligations (CLOs) [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	379,741	[1]	'	357,326	[2]	'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	912	[1]	'	315	[2]	'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-142	[1]	'	0	[2]	'	'	'
Fair Value	380,511	[1]	'	357,641	[2]	'	'	'
Other than temporary impairment	2,800		'	2,600		'	'	'
Pooled trust preferred securities [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	0		'	31,900	[3]	'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	0		'	0	[3]	'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	0	[3]	'	-3,410	[3]	'	'	'
Fair Value	0		'	28,490	[3]	'	'	'
Other than temporary impairment	'		'	-14,000		'	'	'
Single issuer trust preferred securities [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	41,936		'	41,807		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	83		'	0		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	-2,637		'	-6,872		'	'	'
Fair Value	39,382		'	34,935		'	'	'
Corporate debt securities [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	107,132		'	108,936		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	4,068		'	4,155		'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	0		'	0		'	'	'
Fair Value	111,200		'	113,091		'	'	'
Equity securities - financial institutions [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Available for sale - Amortized cost	0		'	2,314	[4]	'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Gains	0		'	1,270	[4]	'	'	'
Available-for-sale - Recognized in OCI - Gross Unrealized Losses	0		'	0	[4]	'	'	'
Fair Value	0		'	3,584	[4]	'	'	'
Other than temporary impairment	'		'	20,400		'	'	'
Municipal bonds and notes [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	377,074		'	448,405		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	15,332		'	11,104		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	-38		'	-1,228		'	'	'
Held to Maturity, Fair Value - Total debt securities	392,368		'	458,281		'	'	'
Private Label MBS [Member]	'		'	'		'	'	'
Schedule of Investments [Line Items]	'		'	'		'	'	'
Held to Maturity, Amortized Cost - Total debt securities	6,478		'	8,498		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Gains	117		'	176		'	'	'
Held-to-maturity - Not Recognized in OCI - Gross Unrealized Losses	0		'	0		'	'	'
Held to Maturity, Fair Value - Total debt securities	$6,595		'	$8,674		'	'	'
[1]	Amortized cost is net of $2.8 million of other-than-temporary impairments at September 30, 2014.
[2]	Amortized cost is net of $2.6 million of other-than-temporary impairments at December 31, 2013.
[3]	Amortized cost is net of $14.0 million of other-than-temporary impairments at December 31, 2013.
[4]	Amortized cost is net of $20.4 million of other-than-temporary impairments at December 31, 2013.

Investment_Securities_Summary_1

Investment Securities (Summary Of Debt Securities By Contractual Maturity) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Fiscal Year Maturity [Abstract]	'	'
Available for Sale, Amortized Cost - Due in one year or less	$15,518	'
Available for Sale, Amortized Cost - Due after one year through five years	107,131	'
Available for Sale, Amortized Cost - Due after five through ten years	260,350	'
Available for Sale, Amortized Cost - Due after ten years	2,470,071	'
Available for Sale, Amortized Cost - Total debt securities	2,853,070	'
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]	'	'
Available for Sale, Fair Value - Due in one year or less	15,546	'
Available for Sale, Fair Value - Due after one year through five years	111,200	'
Available for Sale, Fair Value - Due after five through ten years	260,884	'
Available for Sale, Fair Value - Due after ten years	2,486,256	'
Available for Sale, Fair Value - Total debt securities	2,873,886	'
Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis [Abstract]	'	'
Held to Maturity, Amortized Cost - Due in one year or less	15	'
Held to Maturity, Amortized Cost - Due after one year through five years	70,092	'
Held to Maturity, Amortized Cost - Due after five through ten years	67,799	'
Held to Maturity, Amortized Cost - Due after ten years	3,504,073	'
Held to Maturity, Amortized Cost - Total debt securities	3,641,979	3,358,721
Held-to-maturity Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]	'	'
Held to Maturity, Fair Value - Due in one year or less	15	'
Held-to-maturity, Fair Value, Due after one year through five years	73,095	'
Held to Maturity, Fair Value - Due after five through ten years	70,457	'
Held to Maturity, Fair Value - Due after ten years	3,556,258	'
Held to Maturity, Fair Value - Total debt securities	$3,699,825	$3,370,912

Investment_Securities_Narrativ

Investment Securities (Narrative) (Detail) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	$2,873,886,000		'	$2,873,886,000		'	$3,106,931,000
Pledged securities as required or permitted by law	2,900,000,000		'	2,900,000,000		'	2,700,000,000
Gross Unrealized Losses	-27,779,000		'	-27,779,000		'	-61,626,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	-27,259,000		'	-27,259,000		'	-61,218,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	-27,259,000		'	-27,259,000		'	-61,218,000
Recognized other-than-temporary impairment	-85,000		0	-246,000		0	'
Callable at the option of the counterparty [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	818,000,000		'	818,000,000		'	'
US States and Political Subdivisions Debt Securities [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Investments in obligations of individual states, counties or municipalities	0		'	0		'	0
Agency collateralized mortgage obligations (CMOs) [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	638,223,000		'	638,223,000		'	806,912,000
Gross Unrealized Losses	-1,057,000		'	-1,057,000		'	-1,868,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	-1,409,000		'	-1,409,000		'	-1,009,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	-1,409,000		'	-1,409,000		'	-1,009,000
Agency MBS [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	1,090,820,000		'	1,090,820,000		'	1,226,702,000
Gross Unrealized Losses	-23,539,000		'	-23,539,000		'	-47,698,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	-23,068,000		'	-23,068,000		'	-53,188,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	-23,068,000		'	-23,068,000		'	-53,188,000
Agency commercial mortgage-backed securities (ACMBS) [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	80,383,000		'	80,383,000		'	70,977,000
Gross Unrealized Losses	-349,000		'	-349,000		'	-782,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	-622,000		'	-622,000		'	-818,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	-622,000		'	-622,000		'	-818,000
Commercial mortgage-backed securities (CMBS) [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	532,842,000		'	532,842,000		'	464,274,000
Gross Unrealized Losses	-55,000		'	-55,000		'	-996,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	-2,122,000		'	-2,122,000		'	-4,975,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	-2,122,000		'	-2,122,000		'	-4,975,000
Collateralized loan obligations (CLOs) [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	380,511,000	[1]	'	380,511,000	[1]	'	357,641,000	[2]
Gross Unrealized Losses	-142,000	[1]	'	-142,000	[1]	'	0	[2]
Pooled trust preferred securities [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	0		'	0		'	28,490,000	[3]
Gross Unrealized Losses	0	[3]	'	0	[3]	'	-3,410,000	[3]
Single issuer trust preferred securities [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	39,382,000		'	39,382,000		'	34,935,000
Gross Unrealized Losses	-2,637,000		'	-2,637,000		'	-6,872,000
Corporate debt securities [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	111,200,000		'	111,200,000		'	113,091,000
Gross Unrealized Losses	0		'	0		'	0
Equity securities - financial institutions [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Securities available-for-sale, at fair value	0		'	0		'	3,584,000	[4]
Gross Unrealized Losses	0		'	0		'	0	[4]
Municipal bonds and notes [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	-38,000		'	-38,000		'	-1,228,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	-38,000		'	-38,000		'	-1,228,000
Percentage of bank qualified bonds with credit rating range of AAA to A	'		'	99.30%		'	'
Percentage of municipal bond Portfolio comprised of General Obligation bonds	'		'	86.00%		'	'
Percentage of municipal bond portfolio comprised of Revenue bonds	'		'	13.50%		'	'
Percentage of municipal bond portfolio comprised of other bonds	'		'	0.50%		'	'
Private Label MBS [Member]	'		'	'		'	'
Schedule of Investments [Line Items]	'		'	'		'	'
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	$0		'	$0		'	$0
[1]	Amortized cost is net of $2.8 million of other-than-temporary impairments at September 30, 2014.
[2]	Amortized cost is net of $2.6 million of other-than-temporary impairments at December 31, 2013.
[3]	Amortized cost is net of $14.0 million of other-than-temporary impairments at December 31, 2013.
[4]	Amortized cost is net of $20.4 million of other-than-temporary impairments at December 31, 2013.

Investment_Securities_Summary_2

Investment Securities (Summary Of Gross Unrealized Losses Not Considered OTTI) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	holding	holding
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	$221,237	$893,274
Available for sale, Unrealized Losses - Less Than Twelve Months	-811	-33,409
Available for sale, Fair Value - Twelve Months or Longer	790,414	330,990
Available for sale, Unrealized Losses - Twelve Months or Longer	-26,968	-28,217
Available for sale, Number of Holdings - Total	99	123
Available for sale, Fair Value - Total	1,011,651	1,224,264
Available for sale, Unrealized Losses - Total	-27,779	-61,626
Held-to-maturity, Fair Value - Less Than Twelve Months	575,621	1,342,814
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	-2,597	-49,260
Held-to-maturity, Fair Value - Twelve Months or Longer	773,954	187,778
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	-24,662	-11,958
Held-to-maturity, Number of Holdings - Total	105	164
Held-to-maturity, Fair Value - Total	1,349,575	1,530,592
Held-to-maturity, Unrealized Losses - Total	-27,259	-61,218
Agency CMOs [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	82,646	149,894
Available for sale, Unrealized Losses - Less Than Twelve Months	-278	-1,713
Available for sale, Fair Value - Twelve Months or Longer	35,915	9,011
Available for sale, Unrealized Losses - Twelve Months or Longer	-779	-155
Available for sale, Number of Holdings - Total	10	15
Available for sale, Fair Value - Total	118,561	158,905
Available for sale, Unrealized Losses - Total	-1,057	-1,868
Held-to-maturity, Fair Value - Less Than Twelve Months	111,069	53,789
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	-798	-1,009
Held-to-maturity, Fair Value - Twelve Months or Longer	25,943	'
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	-611	'
Held-to-maturity, Number of Holdings - Total	10	4
Held-to-maturity, Fair Value - Total	137,012	53,789
Held-to-maturity, Unrealized Losses - Total	-1,409	-1,009
Agency MBS [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	55,408	616,286
Available for sale, Unrealized Losses - Less Than Twelve Months	-262	-29,537
Available for sale, Fair Value - Twelve Months or Longer	665,932	279,680
Available for sale, Unrealized Losses - Twelve Months or Longer	-23,277	-18,161
Available for sale, Number of Holdings - Total	73	88
Available for sale, Fair Value - Total	721,340	895,966
Available for sale, Unrealized Losses - Total	-23,539	-47,698
Held-to-maturity, Fair Value - Less Than Twelve Months	258,608	1,045,693
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	-1,161	-42,181
Held-to-maturity, Fair Value - Twelve Months or Longer	671,769	170,780
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	-21,907	-11,007
Held-to-maturity, Number of Holdings - Total	64	94
Held-to-maturity, Fair Value - Total	930,377	1,216,473
Held-to-maturity, Unrealized Losses - Total	-23,068	-53,188
Agency CMBS [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	36,325	70,977
Available for sale, Unrealized Losses - Less Than Twelve Months	-88	-782
Available for sale, Fair Value - Twelve Months or Longer	44,057	'
Available for sale, Unrealized Losses - Twelve Months or Longer	-261	'
Available for sale, Number of Holdings - Total	4	3
Available for sale, Fair Value - Total	80,382	70,977
Available for sale, Unrealized Losses - Total	-349	-782
Held-to-maturity, Fair Value - Less Than Twelve Months	196,139	90,218
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	-622	-818
Held-to-maturity, Fair Value - Twelve Months or Longer	'	'
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	'	'
Held-to-maturity, Number of Holdings - Total	9	4
Held-to-maturity, Fair Value - Total	196,139	90,218
Held-to-maturity, Unrealized Losses - Total	-622	-818
Municipal bonds and notes [Member]	'	'
Schedule of Investments [Line Items]	'	'
Held-to-maturity, Fair Value - Less Than Twelve Months	4,311	46,587
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	-6	-1,193
Held-to-maturity, Fair Value - Twelve Months or Longer	3,075	2,166
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	-32	-35
Held-to-maturity, Number of Holdings - Total	14	51
Held-to-maturity, Fair Value - Total	7,386	48,753
Held-to-maturity, Unrealized Losses - Total	-38	-1,228
CMBS [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	15,000	52,340
Available for sale, Unrealized Losses - Less Than Twelve Months	-41	-996
Available for sale, Fair Value - Twelve Months or Longer	9,390	'
Available for sale, Unrealized Losses - Twelve Months or Longer	-14	'
Available for sale, Number of Holdings - Total	3	7
Available for sale, Fair Value - Total	24,390	52,340
Available for sale, Unrealized Losses - Total	-55	-996
Held-to-maturity, Fair Value - Less Than Twelve Months	5,494	106,527
Held-to-maturity, Unrealized Losses - Less Than Twelve Months	-10	-4,059
Held-to-maturity, Fair Value - Twelve Months or Longer	73,167	14,832
Held-to-maturity, Unrealized Losses, Twelve Months or Longer	-2,112	-916
Held-to-maturity, Number of Holdings - Total	8	11
Held-to-maturity, Fair Value - Total	78,661	121,359
Held-to-maturity, Unrealized Losses - Total	-2,122	-4,975
Collateralized loan obligations (CLOs) [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	31,858	'
Available for sale, Unrealized Losses - Less Than Twelve Months	-142	'
Available for sale, Fair Value - Twelve Months or Longer	'	'
Available for sale, Unrealized Losses - Twelve Months or Longer	'	'
Available for sale, Number of Holdings - Total	2	'
Available for sale, Fair Value - Total	31,858	'
Available for sale, Unrealized Losses - Total	-142	'
Pooled trust preferred securities [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	'	0
Available for sale, Unrealized Losses - Less Than Twelve Months	'	'
Available for sale, Fair Value - Twelve Months or Longer	'	11,141
Available for sale, Unrealized Losses - Twelve Months or Longer	'	-3,410
Available for sale, Number of Holdings - Total	'	2
Available for sale, Fair Value - Total	'	11,141
Available for sale, Unrealized Losses - Total	'	-3,410
Single issuer trust preferred securities [Member]	'	'
Schedule of Investments [Line Items]	'	'
Available for Sale, Fair Value - Less Than Twelve Months	'	3,777
Available for sale, Unrealized Losses - Less Than Twelve Months	'	-381
Available for sale, Fair Value - Twelve Months or Longer	35,120	31,158
Available for sale, Unrealized Losses - Twelve Months or Longer	-2,637	-6,491
Available for sale, Number of Holdings - Total	7	8
Available for sale, Fair Value - Total	35,120	34,935
Available for sale, Unrealized Losses - Total	($2,637)	($6,872)

Investment_Securities_Other_Th

Investment Securities Other Than Temporary Impairment Credit Losses Recognized In Earnings (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]	'	'	'	'
Balance of OTTI, beginning of period	$9,738	$10,460	$16,633	$10,460
Reduction for securities sold, called	-7,026	-1,104	-14,082	-1,104
Additions for OTTI not previously recognized	85	0	246	0
Balance of OTTI, end of period	$2,797	$9,356	$2,797	$9,356

Investment_Securities_Summary_3

Investment Securities (Summary Of Sale Proceeds Of Available For Sale Securities) (Detail) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Investments, Debt and Equity Securities [Abstract]	'		'		'		'
Unsettled sales proceeds	$25,300,000		'		$25,300,000		'
Proceeds from sales of available-for-sale securities	16,380,000	[1]	7,740,000	[1]	38,075,000	[1]	44,261,000	[1]
Gains	1,812,000		269,000		6,148,000		708,000
Losses	-1,770,000		0		-1,770,000		0
OTTI Charges	-85,000		0		-246,000		0
Net	($43,000)		$269,000		$4,132,000		$708,000
[1]	Proceeds from sales, for the three and nine months ended September 30, 2014, does not include $25.3 million of unsettled sales transactions at September 30, 2014. The gross realized gains and gross realized losses for the three and nine months ended September 30, 2014 reflect the unsettled sales transactions.

Loans_And_Leases_Recorded_Inve

Loans And Leases (Recorded Investment In Loans And Leases) (Detail) (USD $)	Sep. 30, 2014		Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]	'		'
Individually evaluated for impairment	$339,506,000	[1]	$352,505,000	[1]
Collectively evaluated for impairment	13,212,647,000	[1]	12,383,704,000	[1]
Total Loans and Leases	13,552,153,000	[1]	12,736,209,000	[1]
Less: Accrued interest	38,651,000	[1]	36,433,000	[1]
Loans and leases	13,513,502,000	[1]	12,699,776,000	[1]
Unamortized premiums	14,500,000		13,300,000
Residential [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Individually evaluated for impairment	144,355,000		142,871,000
Collectively evaluated for impairment	3,321,447,000		3,228,688,000
Total Loans and Leases	3,465,802,000		3,371,559,000
Less: Accrued interest	10,448,000		10,134,000
Loans and leases	3,455,354,000		3,361,425,000
Consumer [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Individually evaluated for impairment	51,503,000		52,179,000
Collectively evaluated for impairment	2,538,505,000		2,492,353,000
Total Loans and Leases	2,590,008,000		2,544,532,000
Less: Accrued interest	8,108,000		7,844,000
Loans and leases	2,581,900,000		2,536,688,000
Commercial [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Individually evaluated for impairment	41,329,000		52,199,000
Collectively evaluated for impairment	3,602,406,000		3,241,045,000
Total Loans and Leases	3,643,735,000		3,293,244,000
Less: Accrued interest	11,744,000		10,393,000
Loans and leases	3,631,991,000		3,282,851,000
Commercial Real Estate [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Individually evaluated for impairment	100,560,000	[2]	105,046,000	[2]
Collectively evaluated for impairment	3,261,898,000	[2]	2,961,378,000	[2]
Total Loans and Leases	3,362,458,000	[2]	3,066,424,000	[2]
Less: Accrued interest	8,351,000	[2]	8,062,000	[2]
Loans and leases	3,354,107,000	[2]	3,058,362,000	[2]
Equipment financing [Member]	'		'
Financing Receivable, Recorded Investment [Line Items]	'		'
Individually evaluated for impairment	1,759,000		210,000
Collectively evaluated for impairment	488,391,000		460,240,000
Total Loans and Leases	490,150,000		460,450,000
Less: Accrued interest	0		0
Loans and leases	$490,150,000		$460,450,000
[1]	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.
[2]	Includes certain loans individually evaluated for impairment under the Company's loan policy that were deemed not to be impaired at both September 30, 2014 and December 31, 2013.

Loans_And_Leases_Narrative_Det

Loans And Leases (Narrative) (Detail) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013
	grade			grade
Loans and Leases Receivable Disclosure [Abstract]	'		'	'		'
Amount of loan pledged as collateral	$5,400,000,000	[1]	'	$5,400,000,000	[1]	'
Interest on non-accrual loans that would have been recorded as additional interest income	3,000,000		3,500,000	7,600,000		10,900,000
Number of Grades	10		'	10		'
Write-down of TDR's	$2,100,000		$3,200,000	$10,300,000		$17,300,000
[1]	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.

Loans_And_Leases_Summary_Of_Lo

Loans And Leases (Summary Of Loan And Lease Portfolio Aging By Class Of Loan) (Detail) (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	$29,709		$35,409
60-89 Days Past Due and Accruing	15,009		13,786
90 Days Past Due and Accruing	1,283		4,540
Non-accrual	140,080		163,228
Total Past Due and Non-accrual	186,081		216,963
Current	13,366,072		12,519,246
Total Loans and Leases	13,552,153	[1]	12,736,209	[1]
Total recorded investment of TDRs	323,131		341,898
1-4 family [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	9,906	[2]	11,721
60-89 Days Past Due and Accruing	6,295	[2]	6,839
90 Days Past Due and Accruing	0	[2]	0
Non-accrual	68,402	[2]	81,520
Total Past Due and Non-accrual	84,603	[2]	100,080
Current	3,381,199	[2]	3,271,479
Total Loans and Leases	3,465,802	[2]	3,371,559
Home equity [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	9,498	[2]	15,332
60-89 Days Past Due and Accruing	7,068	[2]	5,120
90 Days Past Due and Accruing	0	[2]	0
Non-accrual	38,959	[2]	51,788
Total Past Due and Non-accrual	55,525	[2]	72,240
Current	2,429,571	[2]	2,410,953
Total Loans and Leases	2,485,096	[2]	2,483,193
Other consumer [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	671		462
60-89 Days Past Due and Accruing	334		193
90 Days Past Due and Accruing	0		0
Non-accrual	244		140
Total Past Due and Non-accrual	1,249		795
Current	103,663		60,543
Total Loans and Leases	104,912		61,338
Commercial non-mortgage [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	8,402		3,208
60-89 Days Past Due and Accruing	450		984
90 Days Past Due and Accruing	795		4,305
Non-accrual	12,454		10,946
Total Past Due and Non-accrual	22,101		19,443
Current	2,972,897		2,712,870
Total Loans and Leases	2,994,998		2,732,313
Asset-based [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	0		0
60-89 Days Past Due and Accruing	0		0
90 Days Past Due and Accruing	0		0
Non-accrual	0		0
Total Past Due and Non-accrual	0		0
Current	648,737		560,931
Total Loans and Leases	648,737		560,931
Commercial real estate [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	991		4,387
60-89 Days Past Due and Accruing	670		587
90 Days Past Due and Accruing	488		235
Non-accrual	14,443		13,456
Total Past Due and Non-accrual	16,592		18,665
Current	3,131,467		2,842,637
Total Loans and Leases	3,148,059		2,861,302
Commercial construction [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	0		0
60-89 Days Past Due and Accruing	0		0
90 Days Past Due and Accruing	0		0
Non-accrual	3,919		4,237
Total Past Due and Non-accrual	3,919		4,237
Current	210,480		200,886
Total Loans and Leases	214,399		205,123
Finance Leases Financing Receivable [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
30-59 Days Past Due and Accruing	241		299
60-89 Days Past Due and Accruing	192		63
90 Days Past Due and Accruing	0		0
Non-accrual	1,659		1,141
Total Past Due and Non-accrual	2,092		1,503
Current	488,058		458,947
Total Loans and Leases	490,150		460,450
Residential TDR CH 7 Accruing [Member]	'		'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'		'
Total recorded investment of TDRs	$17,600		'
[1]	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.
[2]	A total of $17.6 million residential and consumer loans was reclassified from non-accrual to accrual status as a result of updated regulatory guidance issued in the first quarter of 2014.

Loans_And_Leases_Allowance_For

Loans And Leases (Allowance For Loan And Lease Losses By Portfolio Segment) (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	$154,868	$163,442	$152,573	$177,129
Provision (benefit) charged to expense	9,500	8,500	27,750	24,500
Losses charged off	-11,567	-16,951	-34,442	-56,593
Recoveries	3,681	2,554	10,601	12,509
Balance, end of period	156,482	157,545	156,482	157,545
Individually evaluated for impairment	21,230	23,311	21,230	23,311
Collectively evaluated for impairment	135,252	134,234	135,252	134,234
Residential [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	19,054	26,876	20,580	29,474
Provision (benefit) charged to expense	2,006	1,075	2,711	2,835
Losses charged off	-1,870	-3,800	-4,868	-8,848
Recoveries	261	152	1,028	842
Balance, end of period	19,451	24,303	19,451	24,303
Individually evaluated for impairment	11,501	13,003	11,501	13,003
Collectively evaluated for impairment	7,950	11,300	7,950	11,300
Consumer [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	33,867	49,659	39,551	54,254
Provision (benefit) charged to expense	5,357	-1,732	7,530	7,328
Losses charged off	-6,329	-5,827	-16,501	-23,565
Recoveries	1,947	1,188	4,262	5,271
Balance, end of period	34,842	43,288	34,842	43,288
Individually evaluated for impairment	4,165	3,281	4,165	3,281
Collectively evaluated for impairment	30,677	40,007	30,677	40,007
Commercial [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	51,632	43,847	47,706	46,566
Provision (benefit) charged to expense	2,051	3,783	10,716	8,902
Losses charged off	-2,738	-3,245	-9,571	-13,740
Recoveries	1,017	426	3,111	3,083
Balance, end of period	51,962	44,811	51,962	44,811
Individually evaluated for impairment	1,717	1,630	1,717	1,630
Collectively evaluated for impairment	50,245	43,181	50,245	43,181
Commercial Real Estate [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	34,144	28,457	29,883	30,834
Provision (benefit) charged to expense	68	6,046	6,633	9,146
Losses charged off	-139	-4,069	-2,991	-10,339
Recoveries	120	105	668	898
Balance, end of period	34,193	30,539	34,193	30,539
Individually evaluated for impairment	3,818	5,397	3,818	5,397
Collectively evaluated for impairment	30,375	25,142	30,375	25,142
Equipment financing [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	5,539	3,603	3,912	4,001
Provision (benefit) charged to expense	344	-672	795	-2,711
Losses charged off	-491	-10	-511	-101
Recoveries	336	683	1,532	2,415
Balance, end of period	5,728	3,604	5,728	3,604
Individually evaluated for impairment	29	0	29	0
Collectively evaluated for impairment	5,699	3,604	5,699	3,604
Unallocated [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Roll Forward]	'	'	'	'
Balance, beginning of period	10,632	11,000	10,941	12,000
Provision (benefit) charged to expense	-326	0	-635	-1,000
Losses charged off	0	0	0	0
Recoveries	0	0	0	0
Balance, end of period	10,306	11,000	10,306	11,000
Individually evaluated for impairment	0	0	0	0
Collectively evaluated for impairment	$10,306	$11,000	$10,306	$11,000

Loans_And_Leases_Impaired_Loan

Loans And Leases (Impaired Loans And Leases By Class) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	$372,488	$388,513
Total Recorded Investment	335,385	349,060
Recorded Investment No Allowance	120,285	128,058
Recorded Investment With Allowance	215,100	221,002
Related Valuation Allowance	21,230	20,451
Residential [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	159,486	158,361
Total Recorded Investment	144,355	142,871
Recorded Investment No Allowance	24,272	23,988
Recorded Investment With Allowance	120,083	118,883
Related Valuation Allowance	11,501	10,534
1-4 family [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	159,486	158,361
Total Recorded Investment	144,355	142,871
Recorded Investment No Allowance	24,272	23,988
Recorded Investment With Allowance	120,083	118,883
Related Valuation Allowance	11,501	10,534
Consumer [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	60,717	63,886
Total Recorded Investment	51,503	52,179
Recorded Investment No Allowance	26,885	27,323
Recorded Investment With Allowance	24,618	24,856
Related Valuation Allowance	4,165	4,595
Home equity [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	60,717	63,886
Total Recorded Investment	51,503	52,179
Recorded Investment No Allowance	26,885	27,323
Recorded Investment With Allowance	24,618	24,856
Related Valuation Allowance	4,165	4,595
Commercial [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	50,359	59,279
Total Recorded Investment	41,329	52,199
Recorded Investment No Allowance	17,754	23,138
Recorded Investment With Allowance	23,575	29,061
Related Valuation Allowance	1,717	1,878
Commercial non-mortgage [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	50,359	59,279
Total Recorded Investment	41,329	52,199
Recorded Investment No Allowance	17,754	23,138
Recorded Investment With Allowance	23,575	29,061
Related Valuation Allowance	1,717	1,878
Commercial real estate [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	99,668	106,738
Total Recorded Investment	96,439	101,601
Recorded Investment No Allowance	50,260	53,399
Recorded Investment With Allowance	46,179	48,202
Related Valuation Allowance	3,818	3,444
Commercial real estate [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	90,230	95,013
Total Recorded Investment	88,209	90,976
Recorded Investment No Allowance	42,743	42,774
Recorded Investment With Allowance	45,466	48,202
Related Valuation Allowance	3,786	3,444
Commercial construction [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	9,438	11,725
Total Recorded Investment	8,230	10,625
Recorded Investment No Allowance	7,517	10,625
Recorded Investment With Allowance	713	0
Related Valuation Allowance	32	0
Equipment financing [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	2,258	249
Total Recorded Investment	1,759	210
Recorded Investment No Allowance	1,114	210
Recorded Investment With Allowance	645	0
Related Valuation Allowance	29	0
Finance Leases Financing Receivable [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Unpaid Principal Balance	2,258	249
Total Recorded Investment	1,759	210
Recorded Investment No Allowance	1,114	210
Recorded Investment With Allowance	645	0
Related Valuation Allowance	$29	$0

Loans_And_Leases_Interest_Inco

Loans And Leases (Interest Income From Impaired Loans And Leases, By Class) (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	$342,224	$398,664
Accrued Interest Income	3,152	3,335	9,187	10,209
Cash Basis Interest Income	612	933	1,842	2,777
Residential [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	143,613	145,240
Accrued Interest Income	1,144	1,015	3,482	3,098
Cash Basis Interest Income	305	520	912	1,476
1-4 family [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	143,613	145,240
Accrued Interest Income	1,144	1,015	3,482	3,098
Cash Basis Interest Income	305	520	912	1,476
Consumer [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	51,841	53,850
Accrued Interest Income	372	250	1,100	748
Cash Basis Interest Income	307	413	930	1,301
Home equity [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	51,841	53,850
Accrued Interest Income	372	250	1,100	748
Cash Basis Interest Income	307	413	930	1,301
Commercial [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	46,764	65,808
Accrued Interest Income	617	794	1,787	2,187
Cash Basis Interest Income	0	0	0	0
Commercial non-mortgage [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	46,764	65,808
Accrued Interest Income	617	794	1,787	2,187
Cash Basis Interest Income	0	0	0	0
Commercial real estate [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	99,021	132,630
Accrued Interest Income	1,008	1,270	2,801	4,157
Cash Basis Interest Income	0	0	0	0
Commercial real estate [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	89,593	116,307
Accrued Interest Income	933	1,109	2,585	3,675
Cash Basis Interest Income	0	0	0	0
Commercial construction [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	9,428	16,323
Accrued Interest Income	75	161	216	482
Cash Basis Interest Income	0	0	0	0
Equipment financing [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	985	1,136
Accrued Interest Income	11	6	17	19
Cash Basis Interest Income	0	0	0	0
Finance Leases Financing Receivable [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment	'	'	985	1,136
Accrued Interest Income	11	6	17	19
Cash Basis Interest Income	$0	$0	$0	$0

Loans_And_Leases_Commercial_Co

Loans And Leases (Commercial, Commercial Real Estate Loans And Equipment Financing Loans Segregated By Risk Rating Exposure) (Detail) (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	$13,552,153	[1]	$12,736,209	[1]
Commercial Portfolio Segment [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	3,643,735		3,293,244
Commercial Portfolio Segment [Member] | (1) - (6) Pass [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	3,474,698		3,091,154
Commercial Portfolio Segment [Member] | (7) Special Mention [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	63,830		87,451
Commercial Portfolio Segment [Member] | (8) Substandard [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	105,008		114,199
Commercial Portfolio Segment [Member] | (9) Doubtful [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	199		440
Commercial Portfolio Segment [Member] | (10) Loss [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	0		0
Commercial Real Estate [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	3,362,458	[2]	3,066,424	[2]
Commercial Real Estate [Member] | (1) - (6) Pass [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	3,191,834		2,947,116
Commercial Real Estate [Member] | (7) Special Mention [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	61,354		20,901
Commercial Real Estate [Member] | (8) Substandard [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	108,762		97,822
Commercial Real Estate [Member] | (9) Doubtful [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	508		585
Commercial Real Estate [Member] | (10) Loss [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	0		0
Finance Leases Portfolio Segment [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	490,150		460,450
Finance Leases Portfolio Segment [Member] | (1) - (6) Pass [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	468,407		437,033
Finance Leases Portfolio Segment [Member] | (7) Special Mention [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	2,080		7,979
Finance Leases Portfolio Segment [Member] | (8) Substandard [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	19,663		15,438
Finance Leases Portfolio Segment [Member] | (9) Doubtful [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	0		0
Finance Leases Portfolio Segment [Member] | (10) Loss [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Recorded investment	$0		$0
[1]	Loans and leases include net deferred fees and unamortized premiums of $14.5 million and $13.3 million at September 30, 2014 and December 31, 2013, respectively.
[2]	Includes certain loans individually evaluated for impairment under the Company's loan policy that were deemed not to be impaired at both September 30, 2014 and December 31, 2013.

Loans_And_Leases_Summary_Of_Th

Loans And Leases (Summary Of The Recorded Investment Of Company's TDRs) (Detail) (USD $)	9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013
Financing Receivable, Impaired [Line Items]	'		'
Total recorded investment of TDRs	$323,131		$341,898
Accruing TDRs performing under modified terms more than one year	68.40%		58.20%
Specific reserves for TDRs included in the balance of allowance for loan and lease losses	20,745		20,360
Additional funds committed to borrowers in TDR status	495		1,262
Accruing TDR [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Total recorded investment of TDRs	236,128	[1]	238,926	[1]
Non Accrual TDR [Member]	'		'
Financing Receivable, Impaired [Line Items]	'		'
Total recorded investment of TDRs	$87,003	[1]	$102,972	[1]
[1]	A total of $17.6 million in residential and consumer loans was reclassified from non-accrual to accrual status in the nine months ended September 30, 2014 as a result of updated regulatory guidance issued in the first quarter of 2014.

Loans_and_Leases_Information_o

Loans and Leases (Information on How Loans and Leases were Modified as a TDR) (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
	Contract		Contract		Contract		Contract
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	92		81		217		242
Financing Receivable, Modifications, Post-Modification Recorded Investment	$12,299	[1]	$11,414	[1]	$31,179	[1]	$50,174	[1]
Extended Maturity [Member] | 1-4 family [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	10		10		24		22
Financing Receivable, Modifications, Post-Modification Recorded Investment	1,383	[1]	1,898	[1]	3,191	[1]	4,418	[1]
Extended Maturity [Member] | Home equity [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	4		10		18		20
Financing Receivable, Modifications, Post-Modification Recorded Investment	143	[1]	307	[1]	911	[1]	961	[1]
Extended Maturity [Member] | Commercial non-mortgage [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	0		0		4		2
Financing Receivable, Modifications, Post-Modification Recorded Investment	0	[1]	0	[1]	356	[1]	7,520	[1]
Extended Maturity [Member] | Commercial real estate [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	0		0		0		3
Financing Receivable, Modifications, Post-Modification Recorded Investment	0	[1]	0	[1]	0	[1]	227	[1]
Extended Maturity [Member] | Finance Leases Financing Receivable [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	1		0		1		0
Financing Receivable, Modifications, Post-Modification Recorded Investment	492	[1]	0	[1]	492	[1]	0	[1]
Adjusted Interest Rates [Member] | 1-4 family [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	1		1		3		6
Financing Receivable, Modifications, Post-Modification Recorded Investment	103	[1]	654	[1]	448	[1]	1,888	[1]
Adjusted Interest Rates [Member] | Home equity [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	0		0		1		4
Financing Receivable, Modifications, Post-Modification Recorded Investment	0	[1]	0	[1]	51	[1]	154	[1]
Adjusted Interest Rates [Member] | Commercial non-mortgage [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	0		0		1		0
Financing Receivable, Modifications, Post-Modification Recorded Investment	0	[1]	0	[1]	25	[1]	0	[1]
Adjusted Interest Rates [Member] | Commercial real estate [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	0		2		0		4
Financing Receivable, Modifications, Post-Modification Recorded Investment	0	[1]	340	[1]	0	[1]	12,015	[1]
Rate and Maturity [Member] | 1-4 family [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	2		8		16		38
Financing Receivable, Modifications, Post-Modification Recorded Investment	275	[1]	1,142	[1]	3,522	[1]	7,213	[1]
Rate and Maturity [Member] | Home equity [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	1		3		6		13
Financing Receivable, Modifications, Post-Modification Recorded Investment	110	[1]	164	[1]	412	[1]	1,381	[1]
Rate and Maturity [Member] | Commercial non-mortgage [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	5		12		18		19
Financing Receivable, Modifications, Post-Modification Recorded Investment	342	[1]	353	[1]	974	[1]	982	[1]
Other [Member] | 1-4 family [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	32		5		47		30
Financing Receivable, Modifications, Post-Modification Recorded Investment	7,600	[1]	1,177	[1]	10,433	[1]	5,611	[1]
Other [Member] | Home equity [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	34		28		73		78
Financing Receivable, Modifications, Post-Modification Recorded Investment	1,750	[1]	811	[1]	3,717	[1]	3,197	[1]
Other [Member] | Commercial non-mortgage [Member]	'		'		'		'
Financing Receivable, Impaired [Line Items]	'		'		'		'
Financing Receivable, Modifications, Number of Contracts	2		2		5		3
Financing Receivable, Modifications, Post-Modification Recorded Investment	$101	[1]	$4,568	[1]	$6,647	[1]	$4,607	[1]
[1]	Post-modification balances approximate pre-modification balances. The aggregate amount of charge-offs as a result of the restructurings was not significant.

Loans_and_Leases_Information_o1

Loans and Leases (Information on Loans and Leases Modified as TDR within the Previous 12 Months (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
	loan	loan	loan	loan
Financing Receivable, Modifications [Line Items]	'	'	'	'
Number of Loans and Leases	5	12	7	20
Recorded Investment	$218	$1,669	$244	$2,657
1-4 family [Member]	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'
Number of Loans and Leases	3	8	3	12
Recorded Investment	196	1,116	196	1,814
Home equity [Member]	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'
Number of Loans and Leases	2	3	4	7
Recorded Investment	22	53	48	343
Commercial real estate [Member]	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'
Number of Loans and Leases	0	1	0	1
Recorded Investment	$0	$500	$0	$500

Loans_and_Leases_Investments_i

Loans and Leases (Investments in TDRs, Segregated by Risk Rating Exposure) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	$323,131	$341,898
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	127,076	146,848
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (1) - (6) Pass [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	37,861	55,973
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (7) Special Mention [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	18,268	0
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (8) Substandard [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	70,601	90,461
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (9) Doubtful [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	346	414
Commerial, Commercial Real Estate, Equipment Financing TDR's [Member] | (10) Loss [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Total recorded investment of TDRs	$0	$0

Transfers_of_Financial_Assets_2

Transfers of Financial Assets and Mortgage Servicing Assets - Narrative (Details) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]	'		'	'		'	'
Number of days required to repurchase mortgage loans	'		'	'90 days		'	'
Residential Mortgage [Member]	'		'	'		'	'
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]	'		'	'		'	'
Retained servicing rights	$2,400,000,000		'	$2,400,000,000		'	$2,400,000,000
Bank servicing fees	700,000		400,000	1,400,000		2,500,000	'
Residential Mortgage [Member] | Fair Value, Measurements, Nonrecurring [Member]	'		'	'		'	'
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items]	'		'	'		'	'
Mortgage servicing assets	$19,651,000	[1]	'	$19,651,000	[1]	'	$20,983,000	[1]
[1]	The carrying amount of mortgage servicing assets is net of $11 thousand and $0.2 million reserves at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.

Transfers_of_Financial_Assets_3

Transfers of Financial Assets and Mortgage Servicing Assets Reserve for loan repurchases (Details) (Loan Purchase Commitments [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Loan Purchase Commitments [Member]	'	'	'	'
Movement in Valuation Allowances and Reserves [Roll Forward]	'	'	'	'
Balance, beginning of period	$1,575	$2,648	$2,254	$2,617
Provision (benefit)	132	447	-391	1,462
Loss on repurchased loans and settlements	0	-586	-156	-1,570
Balance, end of period	$1,707	$2,509	$1,707	$2,509

Transfers_of_Financial_Assets_4

Transfers of Financial Assets and Mortgage Servicing Assets Loans sold (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Servicing Assets at Fair Value [Line Items]	'	'	'	'
Net gain on sale included as mortgage banking activities	$1,805	$665	$3,093	$13,584
Residential Portfolio Segment [Member]	'	'	'	'
Servicing Assets at Fair Value [Line Items]	'	'	'	'
Proceeds from the sale of loans held for sale	85,311	199,903	207,530	657,541
Net gain on sale included as mortgage banking activities	1,805	665	3,093	13,900
Loans sold with servicing rights retained	78,848	192,283	193,781	622,550
Commercial Portfolio Segment [Member]	'	'	'	'
Servicing Assets at Fair Value [Line Items]	'	'	'	'
Proceeds from the sale of loans held for sale	0	0	0	12,685
Net gain on sale included as mortgage banking activities	$0	$0	$0	($316)

Recovered_Sheet2

Goodwill And Other Intangible Assets (Goodwill And Other Intangible Assets, Net Of Accumulated Amortization) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Goodwill [Line Items]	'	'
Goodwill	$529,887	$529,887
Community Banking [Member]	'	'
Goodwill [Line Items]	'	'
Goodwill	516,560	516,560
Other [Member]	'	'
Goodwill [Line Items]	'	'
Goodwill	$13,327	$13,327

Recovered_Sheet3

Goodwill And Other Intangible Assets (Gross Carrying Value And Accumulated Amortization Of Other Intangible Assets) (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Dec. 31, 2013
					Community Banking [Member]	Community Banking [Member]
Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'	'
Gross Carrying Amount	'	'	'	'	$49,420	$49,420
Accumulated Amortization	'	'	'	'	-46,338	-44,069
Net Carrying Amount	'	'	'	'	3,082	5,351
Amortization of intangible assets	$432	$1,242	$2,269	$3,726	'	'

Goodwill_And_Other_Intangible_2

Goodwill And Other Intangible Assets (Schedule Of Expected Amortization Expense, Next Four Years) (Detail) (USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]	'
Remainder of 2014	$415
2015	1,524
2016	$1,143

Deposits_Summary_Of_Deposits_D

Deposits (Summary Of Deposits) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Banking and Thrift [Abstract]	'	'
Demand	$3,256,741	$3,128,152
Checking	2,105,481	1,934,291
Health savings accounts	1,765,671	1,533,310
Money market	2,239,106	2,167,593
Savings	3,877,673	3,863,930
Time deposits	2,302,246	2,227,144
Total interest-bearing	12,290,177	11,726,268
Total deposits	15,546,918	14,854,420
Demand deposit overdrafts reclassified as loan balances	$1,791	$1,455

Deposits_Scheduled_Maturities_

Deposits (Scheduled Maturities Of Time Deposits) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Banking and Thrift [Abstract]	'	'
2014	$357,663,000	'
2015	1,041,544,000	'
2016	305,677,000	'
2017	120,685,000	'
2018	149,111,000	'
Thereafter	327,566,000	'
Time deposits	2,302,246,000	2,227,144,000
Interest-bearing Domestic Deposit, Brokered	$350,500,000	$205,900,000

Securities_Sold_Under_Agreemen2

Securities Sold Under Agreements To Repurchase And Other Borrowings (Summary Of Securities Sold Under Agreements To Repurchase And Other Borrowings) (Detail) (USD $)	Sep. 30, 2014		Dec. 31, 2013
Securities Sold Under Agreements to Repurchase and Other Short-term Borrowings [Line Items]	'		'
Securities sold under agreements to repurchase:	$948,975,000		$1,009,662,000
Federal funds purchased	288,000,000		322,000,000
Securities sold under agreements to repurchase and other borrowings	1,236,975,000		1,331,662,000
Gross repurchase agreement liability	900,000,000		'
Original maturity of one year or less [Member]	'		'
Securities Sold Under Agreements to Repurchase and Other Short-term Borrowings [Line Items]	'		'
Securities sold under agreements to repurchase:	398,975,000		359,662,000
Original maturity of greater than one year, non-callable [Member]	'		'
Securities Sold Under Agreements to Repurchase and Other Short-term Borrowings [Line Items]	'		'
Securities sold under agreements to repurchase:	550,000,000		550,000,000
Callable at the option of the counterparty [Member]	'		'
Securities Sold Under Agreements to Repurchase and Other Short-term Borrowings [Line Items]	'		'
Securities sold under agreements to repurchase:	$0	[1]	$100,000,000	[1]
[1]	There were $100 million of securities sold under agreements to repurchase that had callable options for June 23, 2014 and were classified as callable at the option of the counterparty at December 31, 2013. The callable options were not exercised as of the call date and were reclassified as original maturity of greater than one year, non-callable during the quarter ended September 30, 2014.

Federal_Home_Loan_Bank_Advance2

Federal Home Loan Bank Advances (Summary Of Advances Payable To The Federal Home Loan Bank) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Total Outstanding	'	'
Within 1 year	$1,775,000	$1,550,000
After 1 but within 2 years	145,934	0
After 2 but within 3 years	0	145,934
After 3 but within 4 years	100,500	500
After 4 but within 5 years	108,731	200,000
After 5 years	159,996	155,926
Federal Home Loan Bank advances	2,290,161	2,052,360
Unamortized premiums	43	61
Federal Home Loan Bank advances	$2,290,204	$2,052,421
Weighted- Average Contractual Coupon Rate	'	'
Within 1 year	0.20%	0.25%
After 1 but within 2 years	1.80%	0.00%
After 2 but within 3 years	0.00%	1.80%
After 3 but within 4 years	1.49%	5.66%
After 4 but within 5 years	1.33%	1.36%
After 5 years	1.25%	1.25%
Weighted- Average Contractual Coupon Rate	0.48%	0.54%

Federal_Home_Loan_Bank_Advance3

Federal Home Loan Bank Advances (Narrative) (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]	'	'
Collateral pledged	$5,000,000,000	$4,800,000,000
Federal Home Loan Bank Advances [Member]	'	'
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]	'	'
Unused funds	1,000,000,000	1,000,000,000
Line of Credit [Member]	'	'
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]	'	'
Unused funds	$5,000,000	$5,000,000

LongTerm_Debt_Schedule_Of_Long

Long-Term Debt (Schedule Of Long-Term Debt) (Detail) (USD $)

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Feb. 11, 2014

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Feb. 11, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

London Interbank Offered Rate (LIBOR) [Member]

Senior fixed-rate notes [Member]

Junior Subordinated Debt [Member]

Junior Subordinated Debt [Member]

4.375% Maturing 2024 [Member]

4.375% Maturing 2024 [Member]

4.375% Maturing 2024 [Member]

5.125% Maturing 2014 [Member]

5.125% Maturing 2014 [Member]

Senior fixed-rate notes [Member]

Senior fixed-rate notes [Member]

Senior fixed-rate notes [Member]

Senior fixed-rate notes [Member]

Senior fixed-rate notes [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Stated interest rate

'

'

'

'

'

'

'

4.38%

'

5.13%

[1]

'

Senior Notes

'

'

'

'

'

'

$150,000,000

[1]

'

$0

[1]

$0

$150,000,000

Junior Subordinated Notes

'

'

'

'

77,320,000

[2]

77,320,000

[2]

'

'

'

'

'

Total notes and subordinated debt

227,320,000

227,320,000

'

'

'

'

'

'

'

'

'

Unamortized discount, net

-1,112,000

[3]

-21,000

[3]

'

'

'

'

'

'

'

'

'

Deferred (Gain) Loss on Discontinuation of Fair Value Hedge

0

[3]

1,066,000

[3]

'

'

'

'

'

'

'

'

'

Long-term debt

226,208,000

228,365,000

'

'

'

'

'

'

'

'

'

Face amount

'

'

'

150,000,000

'

'

'

'

'

'

'

Proceeds from issuance of senior debt

'

'

'

$148,000,000

'

'

'

'

'

'

'

Interest rate spread of LIBOR plus

'

'

2.95%

'

'

'

'

'

'

'

'

Variable interest rate

3.19%

3.19%

'

'

'

'

'

'

'

'

'

[1]

On February 11, 2014, Webster completed an underwritten public offering of $150.0 million aggregate principal amount of 4.375% senior notes maturing February 15, 2024. Webster received net proceeds of $148.0 million from the public offering

[2]

The interest rate on Webster Statutory Trust I floating-rate notes, which varies quarterly based on 3-month LIBOR plus 2.95%, was 3.185% at September 30, 2014 and 3.194% at December 31, 2013

[3]

Related to senior fixed-rate notes due 2024 at September 30, 2014 and senior fixed-rate notes due 2014 at December 31, 2013

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Loss (Schedule of Other Comprehensive Income (Loss)) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'	'	'	'
Beginning balance	($29,995)	($65,139)	($48,549)	($32,266)
Other comprehensive (loss) income before reclassifications	-7,203	4,445	11,258	-32,349
Amounts reclassified from accumulated other comprehensive (loss) income	1,279	1,753	1,372	5,674
Net current-period other comprehensive (loss) income, net of tax	-5,924	6,198	12,630	-26,675
Ending balance	-35,919	-58,941	-35,919	-58,941
Available For Sale and Transferred Securities [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'	'	'	'
Beginning balance	21,256	2,729	-2,617	42,741
Other comprehensive (loss) income before reclassifications	-8,133	5,330	18,420	-34,400
Amounts reclassified from accumulated other comprehensive (loss) income	36	-173	-2,644	-455
Net current-period other comprehensive (loss) income, net of tax	-8,097	5,157	15,776	-34,855
Ending balance	13,159	7,886	13,159	7,886
Derivative Instruments [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'	'	'	'
Beginning balance	-24,450	-22,872	-18,206	-27,902
Other comprehensive (loss) income before reclassifications	493	-1,413	-8,534	467
Amounts reclassified from accumulated other comprehensive (loss) income	1,180	1,400	3,963	4,550
Net current-period other comprehensive (loss) income, net of tax	1,673	-13	-4,571	5,017
Ending balance	-22,777	-22,885	-22,777	-22,885
Defined Benefit Pension and Postretirement Benefit Plans [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Roll Forward]	'	'	'	'
Beginning balance	-26,801	-44,996	-27,726	-47,105
Other comprehensive (loss) income before reclassifications	437	528	1,372	1,584
Amounts reclassified from accumulated other comprehensive (loss) income	63	526	53	1,579
Net current-period other comprehensive (loss) income, net of tax	500	1,054	1,425	3,163
Ending balance	($26,301)	($43,942)	($26,301)	($43,942)

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Reclassification out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Impairment loss recognized in earnings	($85)	$0	($246)	$0
Income tax expense	-23,679	-18,158	-67,795	-57,915
Total interest expense	-22,544	-21,766	-67,397	-69,085
Compensation and benefits	-66,849	-64,862	-198,931	-196,680
Net income	50,458	47,305	148,737	135,795
Available for sale and transferred securities [Member] | Reclassification out of accumualted comprehensive income [Member]	'	'	'	'
Reclassification out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Net gain on sale of investment securities	42	269	4,378	708
Impairment loss recognized in earnings	-85	0	-246	0
Income tax expense	7	-96	-1,488	-253
Net income	-36	173	2,644	455
Derivative Instruments [Member] | Reclassification out of accumualted comprehensive income [Member]	'	'	'	'
Reclassification out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Income tax expense	673	782	2,226	2,540
Total interest expense	-1,853	-2,182	-6,189	-7,090
Net income	-1,180	-1,400	-3,963	-4,550
Defined benefit pension and postretirement benefit plans [Member] | Reclassification out of accumualted comprehensive income [Member]	'	'	'	'
Reclassification out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Income tax expense	36	295	30	882
Net income	-63	-526	-53	-1,579
Defined benefit pension and postretirement benefit plans [Member] | Reclassification out of accumualted comprehensive income [Member] | Amortization of net loss [Member]	'	'	'	'
Reclassification out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Compensation and benefits	-80	-803	-28	-2,407
Defined benefit pension and postretirement benefit plans [Member] | Reclassification out of accumualted comprehensive income [Member] | Prior service cost [Member]	'	'	'	'
Reclassification out of Accumulated Other Comprehensive Income [Line Items]	'	'	'	'
Compensation and benefits	($19)	($18)	($55)	($54)

Regulatory_Matters_Information

Regulatory Matters (Information On The Capital Ratios) (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'	'
Dividends paid by Webster Bank	$80,000,000	$70,000,000	'
Trust Preferred Securities Included in Tier One Capital	75,000,000	'	75,000,000
Webster Financial Corporation [Member]	'	'	'
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'	'
Total risk-based capital, Actual Amount	2,060,208,000	'	1,965,171,000
Total risk-based capital, Actual Ratio	14.20%	'	14.20%
Total risk-based capital, Minimum Amount	1,163,206,000	'	1,106,203,000
Total risk-based capital, Capital Requirements Ratio	8.00%	'	8.00%
Total risk-based capital, Well Capitalized Amount	1,454,008,000	'	1,382,754,000
Total risk-based capital, Well Capitalized Ratio	10.00%	'	10.00%
Tier 1 capital, Actual Amount	1,898,704,000	'	1,807,642,000
Tier 1 capital, Actual Ratio	13.10%	'	13.10%
Tier 1 capital, Minimum Amount	581,603,000	'	553,101,000
Tier 1 capital, Capital Requirements Ratio	4.00%	'	4.00%
Tier 1 capital, Well Capitalized Amount	872,405,000	'	829,652,000
Tier 1 capital, Well Capitalized Ratio	6.00%	'	6.00%
Tier 1 leverage capital ratio, Actual Amount	1,898,704,000	'	1,807,642,000
Tier 1 leverage capital ratio, Actual Ratio	9.00%	'	9.00%
Tier 1 leverage capital ratio, Minimum Amount	840,727,000	'	801,535,000
Tier 1 leverage capital ratio, Capital Requirements Ratio	4.00%	'	4.00%
Tier 1 leverage capital ratio, Well Capitalized Amount	1,050,909,000	'	1,001,919,000
Tier 1 leverage capital ratio, Well Capitalized Ratio	5.00%	'	5.00%
Webster Bank N.A. [Member]	'	'	'
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'	'
Total risk-based capital, Actual Amount	1,901,130,000	'	1,815,423,000
Total risk-based capital, Actual Ratio	13.10%	'	13.20%
Total risk-based capital, Minimum Amount	1,161,080,000	'	1,104,200,000
Total risk-based capital, Capital Requirements Ratio	8.00%	'	8.00%
Total risk-based capital, Well Capitalized Amount	1,451,350,000	'	1,380,250,000
Total risk-based capital, Well Capitalized Ratio	10.00%	'	10.00%
Tier 1 capital, Actual Amount	1,739,626,000	'	1,658,466,000
Tier 1 capital, Actual Ratio	12.00%	'	12.00%
Tier 1 capital, Minimum Amount	580,540,000	'	552,100,000
Tier 1 capital, Capital Requirements Ratio	4.00%	'	4.00%
Tier 1 capital, Well Capitalized Amount	870,810,000	'	828,150,000
Tier 1 capital, Well Capitalized Ratio	6.00%	'	6.00%
Tier 1 leverage capital ratio, Actual Amount	1,739,626,000	'	1,658,466,000
Tier 1 leverage capital ratio, Actual Ratio	8.30%	'	8.30%
Tier 1 leverage capital ratio, Minimum Amount	839,728,000	'	800,063,000
Tier 1 leverage capital ratio, Capital Requirements Ratio	4.00%	'	4.00%
Tier 1 leverage capital ratio, Well Capitalized Amount	$1,049,660,000	'	$1,000,079,000
Tier 1 leverage capital ratio, Well Capitalized Ratio	5.00%	'	5.00%

Earnings_Per_Common_Share_Earn

Earnings Per Common Share (Earnings Per Share Basic And Diluted) (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Net income available to common shareholders	$47,819	$44,666	$140,820	$127,631
Less: Earnings allocated to participating securities	-171	-162	-530	-497
Net income allocated to common shareholders	$47,648	$44,504	$140,290	$127,134
Weighted average common shares outstanding - basic (in shares)	89,888	89,759	89,850	88,318
Stock options and restricted stock (in shares)	464	451	471	406
Weighted-average common shares outstanding - diluted (in shares)	90,614	90,423	90,591	90,193
Earnings per common share, Basic (in dollars per share)	$0.53	$0.50	$1.56	$1.44
Earnings per common share, Diluted (in dollars per share)	$0.53	$0.49	$1.55	$1.41
Warrants - Series A1 and A2 [Member]	'	'	'	'
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Warrants (in shares)	0	0	0	1,300
Warrants - other [Member]	'	'	'	'
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Warrants (in shares)	262	213	270	169

Earnings_Per_Common_Share_Narr

Earnings Per Common Share (Narrative) (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Warrants - other [Member]	'	'	'	'
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Common stock shares authorized	700,000	700,000	700,000	700,000
Series A Preferred Stock [Member]	'	'	'	'
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Antidilutive securities excluded from computation of earnings per share, amount	1,100,000	1,100,000	1,100,000	1,100,000
Stock Options [Member]	'	'	'	'
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Antidilutive securities excluded from computation of earnings per share, amount	800,000	1,100,000	800,000	1,200,000
Restricted Stock [Member]	'	'	'	'
Earnings Per Share Basic And Diluted By Common Class [Line Items]	'	'	'	'
Antidilutive securities excluded from computation of earnings per share, amount	157,000	189,000	178,000	224,000

Derivative_Financial_Instrumen2

Derivative Financial Instruments Cash Flow Hedges of Interest Rate Risk (Narrative) (Detail) (Cash Flow Hedging [Member], USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative [Line Items]	'	'	'	'
Unamortized loss on termination of cash flow hedges	'	'	$30,900,000	'
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	7,500,000	'	7,500,000	'
Derivative Instruments, Loss Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing	0	0	107,000	0
Designated as Hedging Instrument [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Unamortized loss on termination of cash flow hedges	'	'	8,000,000	'
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$4,600,000	'	$4,600,000	'

Derivative_Financial_Instrumen3

Derivative Financial Instruments Schedule of forward-settle interest rate swaps (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]	'	'
Total Notional Amount	$10,405,957	$13,138,667
Forward Contracts [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Matures June 30, 2019 [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	1	'
Total Notional Amount	25,000	'
Forward Contracts [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Matures October 16, 2019 and November 18, 2019 [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	4	'
Total Notional Amount	100,000	'
Forward Contracts [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Matures January 31, 2020 [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	2	'
Total Notional Amount	50,000	'
Forward Contracts [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Matures June 16, 2020 [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	2	'
Total Notional Amount	$50,000	'

Derivative_Financial_Instrumen4

Derivative Financial Instruments Schedule of interest rate swaps and caps (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]	'	'
Total Notional Amount	$10,405,957	$13,138,667
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Forward Contracts [Member] | Matures July 2019 and August 2019 [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	4	'
Total Notional Amount	100,000	'
Cash Flow Hedging [Member] | Federal Home Loan Bank Advances [Member] | Designated as Hedging Instrument [Member] | Interest Rate Cap [Member] | Matures December 2021 [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	6	'
Total Notional Amount	$150,000	'
Index Rate	3.00%	'

Derivative_Financial_Instrumen5

Derivative Financial Instruments Schedule of interest rate derivatives designated as cash flow hedges (Details) (Designated as Hedging Instrument [Member], Cash Flow Hedging [Member], USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	Derivative	Derivative
Other Assets [Member] | Forward-settle interest rate swap on anticipated debt [Member]	'	'
Derivative [Line Items]	'	'
Derivative Asset, Number of Instruments Held	0	8
Derivative Asset, Notional Amount	$0	$200,000
Derivative Asset, Fair Value	0	3,027
Other Assets [Member] | Interest rate swaps on FHLB advances [Member]	'	'
Derivative [Line Items]	'	'
Derivative Asset, Number of Instruments Held	4	0
Derivative Asset, Notional Amount	100,000	0
Derivative Asset, Fair Value	263	0
Other Assets [Member] | Interest rate swaps on FHLB advances [Member] | Interest rate cap on FHLB advances [Member]	'	'
Derivative [Line Items]	'	'
Derivative Asset, Number of Instruments Held	6	2
Derivative Asset, Notional Amount	150,000	50,000
Derivative Asset, Fair Value	6,094	3,554
Other Liabilities [Member] | Forward-settle interest rate swap on anticipated debt [Member]	'	'
Derivative [Line Items]	'	'
Derivative Liability, Number of Instruments Held	9	5
Derivative Liability, Notional Amount	225,000	125,000
Derivative Liability, Fair Value	($2,812)	($622)

Derivative_Financial_Instrumen6

Derivative Financial Instruments Schedule of the increase/(reduction) to interest expenses on borrowings related to cash flow hedges (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative [Line Items]	'	'	'	'
Interest Expense	$22,544	$21,766	$67,397	$69,085
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest Expense	188	0	188	498
Amount Reclassified From AOCI	1,853	2,182	6,189	7,090
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest rate swaps on FHLB advances [Member] | Interest Rate Swap [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest Expense	188	0	188	498
Amount Reclassified From AOCI	1,355	1,353	4,060	4,604
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest rate swaps on senior fixed-rate notes [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest Expense	0	0	0	0
Amount Reclassified From AOCI	76	'	191	'
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest rate swaps on senior fixed-rate notes [Member] | Interest Rate Swap [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Amount Reclassified From AOCI	'	0	'	0
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest rate swaps on junior subordinated debt [Member] | Interest Rate Swap [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest Expense	0	0	0	0
Amount Reclassified From AOCI	0	0	0	-3
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Interest rate swaps on repurchase agreements [Member] | Interest Rate Swap [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest Expense	0	0	0	0
Amount Reclassified From AOCI	361	829	1,864	2,489
Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] | Bank Time Deposits [Member] | Interest Rate Swap [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Interest Expense	0	0	0	0
Amount Reclassified From AOCI	$61	$0	$74	$0

Derivative_Financial_Instrumen7

Derivative Financial Instruments Schedule of reduction to interest expense on borrowings related to fair value hedges (Details) (Fair Value Hedging [Member], Designated as Hedging Instrument [Member], Interest Expense [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative [Line Items]	'	'	'	'
Net reduction to interest expense on borrowings	$0	($799)	($1,066)	($2,605)
Interest Rate Swap [Member] | Interest rate swaps on senior fixed-rate notes [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Net reduction to interest expense on borrowings	0	-799	-1,066	-2,398
Interest Rate Swap [Member] | Subordinated Debt [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Net reduction to interest expense on borrowings	$0	$0	$0	($207)

Derivative_Financial_Instrumen8

Derivative Financial Instruments Schedule of outstanding interest rate swaps and caps not designated for hedge accounting (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivative [Line Items]	'	'
Total Notional Amount	$10,405,957	$13,138,667
Not Designated as Hedging Instrument [Member]	'	'
Derivative [Line Items]	'	'
Derivative Asset, Gain	9,855	17,062
Derivative Asset, Loss	-24,757	-23,087
Not Designated as Hedging Instrument [Member] | Customer Position [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	269	235
Total Notional Amount	1,931,021	1,563,728
Derivative Asset, Gain	35,207	29,004
Derivative Liability, Loss	-5,534	-11,175
Net	29,673	17,829
Not Designated as Hedging Instrument [Member] | Customer Position [Member] | Other Assets [Member] | Commercial loan interest rate derivatives [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	196	159
Total Notional Amount	1,245,748	915,272
Derivative Asset, Gain	35,207	29,004
Derivative Asset, Loss	0	0
Net	35,207	29,004
Not Designated as Hedging Instrument [Member] | Customer Position [Member] | Other Liabilities [Member] | Commercial loan interest rate derivatives [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	73	76
Total Notional Amount	685,273	648,456
Derivative Liability, Gain	0	0
Derivative Liability, Loss	-5,534	-11,175
Net	-5,534	-11,175
Not Designated as Hedging Instrument [Member] | Counterparty Position [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	273	243
Total Notional Amount	9,930,957	12,763,667
Derivative Asset, Gain	9,855	17,094
Derivative Liability, Loss	-24,757	-23,119
Net	-14,902	-6,025
Not Designated as Hedging Instrument [Member] | Counterparty Position [Member] | Other Assets [Member] | Commercial loan interest rate derivatives [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	84	111
Total Notional Amount	605,806	914,044
Derivative Asset, Gain	4,019	8,944
Derivative Asset, Loss	-2,625	-2,766
Net	1,394	6,178
Not Designated as Hedging Instrument [Member] | Counterparty Position [Member] | Other Liabilities [Member] | Commercial loan interest rate derivatives [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	179	118
Total Notional Amount	1,325,151	649,623
Derivative Liability, Gain	5,828	8,118
Derivative Liability, Loss	-21,682	-20,094
Net	-15,854	-11,976
Not Designated as Hedging Instrument [Member] | Counterparty Position [Member] | Other Liabilities [Member] | Fed Funds futures [Member]	'	'
Derivative [Line Items]	'	'
Number of Instruments	10	14
Total Notional Amount	8,000,000	11,200,000
Derivative Liability, Gain	8	32
Derivative Liability, Loss	-450	-259
Net	($442)	($227)

Derivative_Financial_Instrumen9

Derivative Financial Instruments Schedule of the changes in the fair value of non-hedge accounting derivatives (Detail) (Not Designated as Hedging Instrument [Member], Interest Expense [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Derivative [Line Items]	'	'	'	'
Net increase to other non-interest income	$1,470	$1,061	$4,750	$2,854
Non-hedge derivatives, net [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Net increase to other non-interest income	1,769	1,511	5,335	3,144
Fed funds futures contracts [Member]	'	'	'	'
Derivative [Line Items]	'	'	'	'
Net increase to other non-interest income	($299)	($450)	($585)	($290)

Recovered_Sheet4

Derivative Financial Instruments Schedule of financial assets and liabilities for non-customer derivative positions (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	$10,405,957		$13,138,667
Total MTM(Loss) Gain	-11,357		-66
Cash Collateral Posted	23,505		8,115
Dealer A [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	452,476		387,258
Total MTM(Loss) Gain	-4,147		-4,274
Cash Collateral Posted	4,200		4,300
Net Exposure	53	[1]	26	[1]
Dealer B [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	327,019		322,888
Total MTM(Loss) Gain	-2,889		-5,010
Cash Collateral Posted	3,160		4,940
Net Exposure	271	[1]	0	[1]
Dealer C [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	11,714		14,477
Total MTM(Loss) Gain	-908		-1,348
Cash Collateral Posted	0		0
Net Exposure	0	[1]	0	[1]
Dealer D [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	318,886		291,627
Total MTM(Loss) Gain	2,128		5,250
Cash Collateral (Received)	-2,200		-5,300
Net Exposure	0	[1]	0	[1]
Dealer E [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	386,920		372,771
Total MTM(Loss) Gain	3,329		3,549
Cash Collateral (Received)	-3,250		-3,310
Net Exposure	0	[1]	0	[1]
Dealer F [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
Total Notional Amount	8,908,942	[2]	11,749,646	[2]
Total MTM(Loss) Gain	-8,870	[2]	1,767	[2]
Cash Collateral Posted	21,595	[2]	7,485	[2]
Net Exposure	12,725	[1],[2]	9,252	[1],[2]
Designated as Hedging Instrument [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	6,357		6,581
MTM Loss	-2,812		-622
Designated as Hedging Instrument [Member] | Dealer A [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	263		730
MTM Loss	0		0
Designated as Hedging Instrument [Member] | Dealer B [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	2,031		615
MTM Loss	0		0
Designated as Hedging Instrument [Member] | Dealer C [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	0		0
MTM Loss	0		0
Designated as Hedging Instrument [Member] | Dealer D [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	1,016		1,734
MTM Loss	0		0
Designated as Hedging Instrument [Member] | Dealer E [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	3,047		2,290
MTM Loss	0		-15
Designated as Hedging Instrument [Member] | Dealer F [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	0	[2]	1,212	[2]
MTM Loss	-2,812	[2]	-607	[2]
Non-Hedge Accounting [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	9,855		17,062
MTM Loss	-24,757		-23,087
Non-Hedge Accounting [Member] | Dealer A [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	3,045		4,643
MTM Loss	-7,455		-9,647
Non-Hedge Accounting [Member] | Dealer B [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	1,933		3,475
MTM Loss	-6,853		-9,100
Non-Hedge Accounting [Member] | Dealer C [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	0		0
MTM Loss	-908		-1,348
Non-Hedge Accounting [Member] | Dealer D [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	2,219		4,108
MTM Loss	-1,107		-592
Non-Hedge Accounting [Member] | Dealer E [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	1,800		3,017
MTM Loss	-1,518		-1,743
Non-Hedge Accounting [Member] | Dealer F [Member]	'		'
Offsetting Assets and Liabilities [Line Items]	'		'
MTM Gain	858	[2]	1,819	[2]
MTM Loss	($6,916)	[2]	($657)	[2]
[1]	Net positive exposure represents over-collateralized loss positions which can be the result of DCO initial margin requirements posted in compliance with the Dodd-Frank Wall Street Reform and Consumer Protection Act.
[2]	Dealer F represents Chicago Mercantile Exchange, our designated DCO.

Recovered_Sheet5

Derivative Financial Instruments Counterparty Credit Risk Narrative (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
Derivative [Line Items]	'	'
Cash Collateral Posted	($23,505,000)	($8,115,000)
Current Derivative Credit Exposure [Member] | Interest Rate Swaps With Bank Customers [Member]	'	'
Derivative [Line Items]	'	'
Maximum exposure	35,200,000	'
Future Derivative Credit Exposure [Member] | Interest Rate Swaps With Bank Customers [Member]	'	'
Derivative [Line Items]	'	'
Maximum exposure	14,200,000	'
Dealer D [Member]	'	'
Derivative [Line Items]	'	'
Cash Collateral Posted	-29,000,000	'
Cash collateral	($5,500,000)	'

Recovered_Sheet6

Derivative Financial Instruments Futures Contracts Derivatives Narrative (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014
In Thousands, unless otherwise specified			Future [Member]
Derivative [Line Items]	'	'	'
Total Notional Amount	$10,405,957	$13,138,667	$800,000
Derivative period	'	'	'1 year
Fair value of contracts	'	'	($442)

Recovered_Sheet7

Derivative Financial Instruments Mortgage Banking Derivatives Narrative (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2013
		Not Designated as Hedging Instrument [Member]	Not Designated as Hedging Instrument [Member]	Not Designated as Hedging Instrument [Member]	Not Designated as Hedging Instrument [Member]
				Other Assets [Member]	Other Assets [Member]
				Mortgage Banking Derivatives [Member]	Mortgage Banking Derivatives [Member]
Derivative [Line Items]	'	'	'	'	'
Outstanding rate locks	$44,800,000	'	'	'	'
Outstanding commitments to sell residential mortgage loans	58,700,000	'	'	'	'
Mandatory forward commitments	56,700,000	'	'	'	'
MTM Gain	'	$9,855,000	$17,062,000	$400,000	$500,000

Fair_Value_Measurements_Narrat

Fair Value Measurements (Narrative) (Detail) (USD $)	Sep. 30, 2014		Dec. 31, 2013		Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014	Sep. 30, 2014
					Alternative investments [Member]	Cost-method Investments [Member]	Fair Value, Measurements, Recurring [Member]	Fair Value, Measurements, Recurring [Member]	Fair Value, Measurements, Recurring [Member]	Fair Value, Measurements, Nonrecurring [Member]
						Alternative investments [Member]	Alternative investments [Member]	Alternative investments [Member]	Cost-method Investments [Member]	Fair Value, Inputs, Level 3 [Member]
									Rabbi Trust [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'		'		'	'	'	'	'	'
Debt Instrument, Unamortized Discount	$1,112,000	[1]	$21,000	[1]	'	'	'	'	'	'
Alternative investments (cost basis)	'		'		'	16,200,000	477,000	565,000	4,600,000	'
Unfunded commitment for investments	'		'		6,900,000	'	'	'	'	'
Book value of other real estate owned (OREO) and repossessed assets	'		'		'	'	'	'	'	$5,200,000
[1]	Related to senior fixed-rate notes due 2024 at September 30, 2014 and senior fixed-rate notes due 2014 at December 31, 2013

Fair_Value_Measurements_Fair_V

Fair Value Measurements (Fair Value Assets And Liabilities Measured On Recurring Basis) (Detail) (Fair Value, Measurements, Recurring [Member], USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	$2,873,886	$3,106,931
Total financial assets held at fair value	2,923,630	3,155,928
Derivative instruments	24,820	24,038
Total financial liabilities held at fair value	24,820	24,038
Investments held In Rabbi Trust [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	5,841	6,097
Alternative investments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	477	565
Derivative instruments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	43,039	41,795
Mortgage banking derivatives [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	387	540
U.S. Treasury Bills [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	525	325
Agency CMOs [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	638,223	806,912
Agency MBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	1,090,820	1,226,702
Agency CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	80,383	70,977
CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	532,842	464,274
Collateralized loan obligations (CLOs) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	380,511	357,641
Pooled trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	28,490
Single issuer trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	39,382	34,935
Corporate debt [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	111,200	113,091
Equity securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	3,584
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	525	3,634
Total financial assets held at fair value	6,374	9,763
Derivative instruments	450	259
Total financial liabilities held at fair value	450	259
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Investments held In Rabbi Trust [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	5,841	6,097
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Alternative investments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	0	0
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Derivative instruments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	8	32
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Mortgage banking derivatives [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	0	0
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | U.S. Treasury Bills [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	525	325
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Agency CMOs [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Agency MBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Agency CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	0	0
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	0	0
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Collateralized loan obligations (CLOs) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Pooled trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Single issuer trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Corporate debt [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Equity securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	3,309
Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	2,873,361	3,074,807
Total financial assets held at fair value	2,916,779	3,117,110
Derivative instruments	24,370	23,779
Total financial liabilities held at fair value	24,370	23,779
Significant Other Observable Inputs (Level 2) [Member] | Investments held In Rabbi Trust [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	'	'
Significant Other Observable Inputs (Level 2) [Member] | Alternative investments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	0	0
Significant Other Observable Inputs (Level 2) [Member] | Derivative instruments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	43,031	41,763
Significant Other Observable Inputs (Level 2) [Member] | Mortgage banking derivatives [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	387	540
Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury Bills [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Other Observable Inputs (Level 2) [Member] | Agency CMOs [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	638,223	806,912
Significant Other Observable Inputs (Level 2) [Member] | Agency MBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	1,090,820	1,226,702
Significant Other Observable Inputs (Level 2) [Member] | Agency CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	80,383	70,977
Significant Other Observable Inputs (Level 2) [Member] | CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	532,842	464,274
Significant Other Observable Inputs (Level 2) [Member] | Collateralized loan obligations (CLOs) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	380,511	357,641
Significant Other Observable Inputs (Level 2) [Member] | Pooled trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Other Observable Inputs (Level 2) [Member] | Single issuer trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	39,382	34,935
Significant Other Observable Inputs (Level 2) [Member] | Corporate debt [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	111,200	113,091
Significant Other Observable Inputs (Level 2) [Member] | Equity securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	275
Significant Unobservable Input (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	28,490
Total financial assets held at fair value	477	29,055
Derivative instruments	'	'
Total financial liabilities held at fair value	'	'
Significant Unobservable Input (Level 3) [Member] | Investments held In Rabbi Trust [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	'	'
Significant Unobservable Input (Level 3) [Member] | Alternative investments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Other assets	477	565
Significant Unobservable Input (Level 3) [Member] | Derivative instruments [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	'	0
Significant Unobservable Input (Level 3) [Member] | Mortgage banking derivatives [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Derivative assets	0	0
Significant Unobservable Input (Level 3) [Member] | U.S. Treasury Bills [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Unobservable Input (Level 3) [Member] | Agency CMOs [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Unobservable Input (Level 3) [Member] | Agency MBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Unobservable Input (Level 3) [Member] | Agency CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	0	0
Significant Unobservable Input (Level 3) [Member] | CMBS [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	0	0
Significant Unobservable Input (Level 3) [Member] | Collateralized loan obligations (CLOs) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Unobservable Input (Level 3) [Member] | Pooled trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	28,490
Significant Unobservable Input (Level 3) [Member] | Single issuer trust preferred securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Unobservable Input (Level 3) [Member] | Corporate debt [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'
Significant Unobservable Input (Level 3) [Member] | Equity securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available for sale securities	'	'

Fair_Value_Measurements_Schedu

Fair Value Measurements (Schedule Of Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'		'		'		'
Level 3, beginning of period	$11,668		$31,572		$29,055		$116,280
Transfers out of Level 3	0	[1]	0	[1]	0	[1]	-248,844	[1]
Change in unrealized loss included in other comprehensive income	3,216		7,194		3,410		14,194
Unrealized loss included in net income	-29		-70		-261		-355
Realized gain on sale of available for sale securities	-1,680		269		2,656		269
Purchases/capital calls	173		0		173		159,412
Sales/proceeds	-12,881		-7,740		-34,576		-7,740
Accretion/amortization	10		26		62		214
Calls/paydowns	0		-483		-42		-2,662
Level 3, end of period	$477		$30,768		$477		$30,768
[1]	As of April 1, 2013, the CLO portfolio was transferred from Level 3 to Level 2 based on having more observable inputs in determining fair value. In prior quarters, the CLO portfolio was priced using average non-binding broker quotes. During the second quarter of 2013, the Company engaged a third-party pricing vendor to provide monthly fair value measurements. This methodology used is a combination of matrix pricing, observed market activity and metrics. Pricing inputs such as credit spreads are observable and market corroborated and, therefore, the CLO portfolio qualifies for Level 2 categorization. The market for CLO is an active market, and there is ample price transparency.

Fair_Value_Measurements_Schedu1

Fair Value Measurements (Schedule Of Valuation Methodology And Unobservable Inputs) (Detail) (USD $)

9 Months Ended

9 Months Ended

9 Months Ended

In Thousands, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Fair Value, Inputs, Level 3 [Member]

Fair Value, Inputs, Level 3 [Member]

Other Real Estate Owned [Member]

Other Real Estate Owned [Member]

Other Real Estate Owned [Member]

Other Real Estate Owned [Member]

Impaired Loans [Member]

Impaired Loans [Member]

Impaired Loans [Member]

Impaired Loans [Member]

Impaired Loans [Member]

Prepayment speeds [Member]

Discount rate [Member]

Prepayment speeds [Member]

Discount rate [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Discount for costs to sell [Member]

Minimum [Member]

Maximum [Member]

Fair Value, Inputs, Level 3 [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Fair Value, Inputs, Level 3 [Member]

Discount for appraisal type [Member]

Discount for appraisal type [Member]

Fair Value, Measurements, Nonrecurring [Member]

Discount for date appraisal [Member]

Discount for costs to sell [Member]

Discount for date appraisal [Member]

Discount for costs to sell [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value Measurements [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Impaired loans and leases

'

'

'

'

$13,377,939

$12,515,714

'

'

'

'

'

'

'

'

$40,927

Other real estate owned

'

'

'

'

'

'

'

'

'

831

'

'

'

'

'

Mortgage servicing assets

'

'

'

'

$29,213

[1]

$29,150

[1]

'

'

'

'

'

'

'

'

'

Range of Inputs

6.80%

1.40%

25.30%

3.70%

'

'

8.00%

0.00%

25.00%

'

2.00%

0.00%

15.00%

8.00%

'

[1]

The carrying amount of mortgage servicing assets is net of $11 thousand and $0.2 million reserves at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.

Fair_Value_Measurements_Summar

Fair Value Measurements (Summary Of Estimated Fair Values Of Significant Financial Instruments) (Detail) (USD $)	Sep. 30, 2014		Dec. 31, 2013
Fair Value Measurements [Line Items]	'		'
Valuation Allowance for Impairment of Recognized Servicing Assets, Balance	$11,000		$200,000
Unamortized premiums	43,000		61,000
Debt Instrument, Unamortized Discount	1,112,000	[1]	21,000	[1]
Hedge accounting adjustments	'		1,000,000
Fair Value, Measurements, Recurring [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Securities held-to-maturity	2,873,886,000		3,106,931,000
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Securities held-to-maturity	2,873,361,000		3,074,807,000
Federal Funds Purchased and Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure	1,257,595,000		1,365,427,000
Federal Home Loan Bank advances	2,301,591,000	[2]	2,063,312,000	[2]
Long-term debt	223,278,000	[3]	221,613,000	[3]
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Securities held-to-maturity [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Securities held-to-maturity	3,699,825,000		3,370,912,000
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Deposits other than time deposits [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Deposits	13,244,672,000		12,627,276,000
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Time deposits [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Deposits	2,317,764,000		2,250,141,000
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Input (Level 3) [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Securities held-to-maturity	'		28,490,000
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Input (Level 3) [Member] | Alternative investments (cost basis) [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Other assets	19,208,000		17,047,000
Fair Value, Measurements, Recurring [Member] | Reported Value Measurement [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Federal Funds Purchased and Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure	1,236,975,000		1,331,662,000
Federal Home Loan Bank advances	2,290,204,000	[2]	2,052,421,000	[2]
Long-term debt	226,208,000	[3]	228,365,000	[3]
Fair Value, Measurements, Recurring [Member] | Reported Value Measurement [Member] | Securities held-to-maturity [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Securities held-to-maturity	3,641,979,000		3,358,721,000
Fair Value, Measurements, Recurring [Member] | Reported Value Measurement [Member] | Alternative investments (cost basis) [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Other assets	16,188,000		16,582,000
Fair Value, Measurements, Recurring [Member] | Reported Value Measurement [Member] | Deposits other than time deposits [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Deposits	13,244,672,000		12,627,276,000
Fair Value, Measurements, Recurring [Member] | Reported Value Measurement [Member] | Time deposits [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Deposits	2,302,246,000		2,227,144,000
Fair Value, Measurements, Nonrecurring [Member] | Residential Mortgage [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Mortgage servicing assets	19,651,000	[4]	20,983,000	[4]
Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs (Level 2) [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Loans held for sale	26,453,000		20,903,000
Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Input (Level 3) [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Loans and leases, net	13,377,939,000		12,515,714,000
Mortgage servicing assets	29,213,000	[4]	29,150,000	[4]
Fair Value, Measurements, Nonrecurring [Member] | Reported Value Measurement [Member]	'		'
Fair Value Measurements [Line Items]	'		'
Loans held for sale	26,083,000		20,802,000
Loans and leases, net	$13,357,020,000		$12,547,203,000
[1]	Related to senior fixed-rate notes due 2024 at September 30, 2014 and senior fixed-rate notes due 2014 at December 31, 2013
[2]	The carrying amount of FHLB advances is net of $43 thousand and $61 thousand in hedge accounting adjustments and discounts at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.
[3]	The carrying amount of long-term debt is net of $1.1 million in discount at September 30, 2014 and $1.0 million in discount and hedge accounting adjustments, net at December 31, 2013. The estimated fair value does not include such adjustments.
[4]	The carrying amount of mortgage servicing assets is net of $11 thousand and $0.2 million reserves at September 30, 2014 and December 31, 2013, respectively. The estimated fair value does not include such adjustments.

Pension_and_Other_Postretireme2

Pension and Other Postretirement Benefits (Summary of Net Periodic Benefit Costs) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Webster Pension [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	$10	$10	$30	$30
Interest cost on projected benefit obligations	2,046	1,841	6,051	5,524
Expected return on plan assets	-2,871	-2,779	-8,621	-8,336
Amortization of prior service cost	0	0	0	0
Recognized net loss	711	1,590	2,086	4,767
Net periodic benefit cost (income)	-104	662	-454	1,985
Webster SERP [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	0	0	0	0
Interest cost on projected benefit obligations	89	72	273	217
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	0	0	0	0
Recognized net loss	55	32	101	94
Net periodic benefit cost (income)	144	104	374	311
Other Benefits [Member]	'	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'	'
Service cost	0	0	0	0
Interest cost on projected benefit obligations	36	30	104	90
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	18	18	55	54
Recognized net loss	4	7	4	21
Net periodic benefit cost (income)	$58	$55	$163	$165

Recovered_Sheet8

Pension And Other Postretirement Benefits (Narrative) (Detail) (Multiemployer Plans, Pension [Member], USD $)	Jul. 01, 2013
In Millions, unless otherwise specified
Multiemployer Plans, Pension [Member]	'
Multiemployer Plans [Line Items]	'
Overfunded amount	$0.30

Pension_and_Other_Postretireme3

Pension and Other Postretirement Benefits (Summary of contributions and funding status) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Compensation and Retirement Disclosure [Abstract]	'	'	'	'
Contributions	$0	$60	$674	$534
Funded Status of Plan	'	'	'At least 80 percent	'

StockBased_Compensation_Plans_1

Stock-Based Compensation Plans (Narrative) (Detail)

9 Months Ended

9 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Restricted Stock [Member]

Time Based Restricted Stock Awards [Member]

Time Based Restricted Stock Awards [Member]

Time Based Restricted Stock Awards [Member]

Performance Based Restricted Stock Awards [Member]

Performance Based Restricted Stock Awards [Member]

Performance Based Restricted Stock Awards [Member]

Performance Based Restricted Stock Awards [Member]

Performance Based Restricted Stock Awards [Member]

Stock options [Member]

Stock options [Member]

Stock options [Member]

Non-Qualified Stock Options [Member]

Incentive Stock Options [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Vesting Period 1 [Member]

Vesting Period 2 [Member]

Vesting Period 1 [Member]

Vesting Period 2 [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Vesting period

'

'

'1 year

'

'1 year

'5 years

'3 years

'

'

'

'

'

'3 years

'4 years

'

'

Shares authorized

'

'

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

Vesting percentage

'

'

'

'

'

'

50.00%

0.00%

0.00%

200.00%

150.00%

'

'

'

'

'

Maximum contractual term

'

'

'

'

'

'

'

'

'

'

'

'10 years

'

'

'

'

Options granted

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of options outstanding

2,122,576

2,325,797

'

'

'

'

'

'

'

'

'

'

'

'

1,942,570

180,006

StockBased_Compensation_Plans_2

Stock-Based Compensation Plans (Summary of Stock-based compensation expense recognized) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Stock-based compensation	$2,243	$2,162	$7,793	$7,757
Stock options [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Stock-based compensation	167	886	943	2,832
Restricted stock [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Stock-based compensation	$2,076	$1,276	$6,850	$4,925

StockBased_Compensation_Plans_3

Stock-Based Compensation Plans (Summary of Unrecognized Compensation Expense) (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014
Stock Options [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized Compensation Expense, Stock options	$654
Weighted-Average Period To Be Recognized	'1 year 3 months
Restricted stock [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized Compensation Expense, Restricted stock	$11,659
Weighted-Average Period To Be Recognized	'2 years 0 months

StockBased_Compensation_Plans_4

Stock-Based Compensation Plans (Summary of Restricted Stock and Stock Option Activity) (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]	'
Options outstanding, at beginning of period, Number of Shares	2,325,797
Options granted, Number of Shares	0
Exercised options, Number of Shares	-108,841
Options forfeited or expired, Number of Shares	-94,380
Options outstanding, at end of period, Number of Shares	2,122,576
Options exercisable, at end of period, Number of Shares	1,814,294
Options expected to vest, at end of period, Number of Shares	294,667
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'
Options, at beginning of period, Weighted-average Exercise Price (in dollars per share)	$26.97
Options granted, Weighted-Average Exercise Price (in dollars per share)	$0
Options exercised, Weighted-Average Exercise Price (in dollars per share)	$15.98
Options forfeited, Weighted-Average Exercise Price (in dollars per share)	$35.30
Options, at end of period, Weighted-average Exercise Price (in dollars per share)	$27.16
Options exercisable, at end of period, Weighted-Average Exercise Price (in dollars per share)	$27.83
Options expected to vest, at end of period, Weighted-Average Exercise Price (in dollars per share)	$23.24
Time Based Restricted Stock Unit Awards [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]	'
Restricted stock, Outstanding at beginning of period	1,705
Restricted stock, Granted	13,678
Restricted stock, Vested restricted stock awards	-9,685	[1]
Restricted stock, Forfeited	0
Restricted stock, Outstanding at end of period	5,698
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'
Restricted stock, at beginning of period, Weighted-average Grant Date Fair Value (in dollars per share)	$22.75
Restricted stock, Granted	$29.34
Restricted stock, Vested restricted stock awards	$28.18	[1]
Restricted stock, Forfeited	$0
Restricted stock, at end of period, Weighted-average Grant Date Fair Value (in dollars per share)	$29.34
Performance Shares [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]	'
Restricted stock, Outstanding at beginning of period	138,450
Restricted stock, Granted	146,248
Restricted stock, Vested restricted stock awards	-113,394	[1]
Restricted stock, Forfeited	-16,909
Restricted stock, Outstanding at end of period	154,395
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'
Restricted stock, at beginning of period, Weighted-average Grant Date Fair Value (in dollars per share)	$24.43
Restricted stock, Granted	$29.94
Restricted stock, Vested restricted stock awards	$25.84	[1]
Restricted stock, Forfeited	$26.47
Restricted stock, at end of period, Weighted-average Grant Date Fair Value (in dollars per share)	$28.40
Restricted Stock [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]	'
Restricted stock, Outstanding at beginning of period	267,119
Restricted stock, Granted	215,412
Restricted stock, Vested restricted stock awards	-166,008	[1]
Restricted stock, Forfeited	-21,941
Restricted stock, Outstanding at end of period	294,582
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]	'
Restricted stock, at beginning of period, Weighted-average Grant Date Fair Value (in dollars per share)	$22.96
Restricted stock, Granted	$29.65
Restricted stock, Vested restricted stock awards	$24.68	[1]
Restricted stock, Forfeited	$25.27
Restricted stock, at end of period, Weighted-average Grant Date Fair Value (in dollars per share)	$26.71
[1]	Vested for purposes of recording compensation expense.

Segment_Reporting_Operating_Re

Segment Reporting - Operating Results and Total Assets Reportable Segments (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
			Segment
Segment Reporting Information [Line Items]	'	'	'	'	'
Number of Reportable Segments	'	'	3	'	'
Provision Expense Attributable To Business Segments And Reported	100.30%	125.00%	110.00%	111.60%	'
Net interest income (loss)	$157,370	$149,987	$467,793	$442,844	'
Provision (benefit) for loan and lease losses	9,500	8,500	27,750	24,500	'
Net interest income after provision for loan and lease losses	147,870	141,487	440,043	418,344	'
Non-interest income	50,909	46,257	148,333	146,786	'
Non-interest expense	124,642	122,281	371,844	371,420	'
Income before income tax expense	74,137	65,463	216,532	193,710	'
Income tax expense (benefit)	23,679	18,158	67,795	57,915	'
Net income	50,458	47,305	148,737	135,795	'
Total Assets	21,826,882	'	21,826,882	'	20,852,999
Segment Totals [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Net interest income (loss)	161,968	155,112	474,143	450,053	'
Provision (benefit) for loan and lease losses	9,525	10,624	30,521	27,337	'
Net interest income after provision for loan and lease losses	152,443	144,488	443,622	422,716	'
Non-interest income	45,639	42,288	131,421	132,770	'
Non-interest expense	119,987	119,308	360,943	362,939	'
Income before income tax expense	78,095	67,468	214,100	192,547	'
Income tax expense (benefit)	24,898	18,792	67,034	57,567	'
Net income	53,197	48,676	147,066	134,980	'
Total Assets	14,705,218	'	14,705,218	'	13,857,335
Commercial Banking [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Net interest income (loss)	61,249	56,430	175,058	161,008	'
Provision (benefit) for loan and lease losses	3,340	7,032	18,031	11,449	'
Net interest income after provision for loan and lease losses	57,909	49,398	157,027	149,559	'
Non-interest income	8,861	8,818	24,761	20,537	'
Non-interest expense	25,445	24,647	76,579	74,068	'
Income before income tax expense	41,325	33,569	105,209	96,028	'
Income tax expense (benefit)	13,148	9,347	32,940	28,710	'
Net income	28,177	24,222	72,269	67,318	'
Total Assets	6,251,726	'	6,251,726	'	5,682,129
Community Banking [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Net interest income (loss)	88,602	87,949	263,893	259,037	'
Provision (benefit) for loan and lease losses	6,159	3,570	12,156	15,816	'
Net interest income after provision for loan and lease losses	82,443	84,379	251,737	243,221	'
Non-interest income	27,307	25,387	77,571	87,654	'
Non-interest expense	79,735	82,748	241,314	251,759	'
Income before income tax expense	30,015	27,018	87,994	79,116	'
Income tax expense (benefit)	9,588	7,504	27,551	23,654	'
Net income	20,427	19,514	60,443	55,462	'
Total Assets	8,062,212	'	8,062,212	'	7,809,343
Other [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Net interest income (loss)	12,117	10,733	35,192	30,008	'
Provision (benefit) for loan and lease losses	26	22	334	72	'
Net interest income after provision for loan and lease losses	12,091	10,711	34,858	29,936	'
Non-interest income	9,471	8,083	29,089	24,579	'
Non-interest expense	14,807	11,913	43,050	37,112	'
Income before income tax expense	6,755	6,881	20,897	17,403	'
Income tax expense (benefit)	2,162	1,941	6,543	5,203	'
Net income	4,593	4,940	14,354	12,200	'
Total Assets	391,280	'	391,280	'	365,863
Corporate and Reconciling [Member]	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'
Net interest income (loss)	-4,598	-5,125	-6,350	-7,209	'
Provision (benefit) for loan and lease losses	-25	-2,124	-2,771	-2,837	'
Net interest income after provision for loan and lease losses	-4,573	-3,001	-3,579	-4,372	'
Non-interest income	5,270	3,969	16,912	14,016	'
Non-interest expense	4,655	2,973	10,901	8,481	'
Income before income tax expense	-3,958	-2,005	2,432	1,163	'
Income tax expense (benefit)	-1,219	-634	761	348	'
Net income	-2,739	-1,371	1,671	815	'
Total Assets	$7,121,664	'	$7,121,664	'	$6,995,664

Commitments_and_Contingencies_1

Commitments and Contingencies - Narrative (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]	'	'	'	'
Rental expense under leases	$5.20	$5.20	$15.30	$15.30
Rental income	$0.20	$0.20	$0.60	$0.70

Commitments_and_Contingencies_2

Commitments and Contingencies - Outstanding Financial Instruments Contract Amounts Represent Credit Risk (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Loss Contingencies [Line Items]	'	'
Total financial instruments with off-balance sheet risk	$4,563,478	$4,276,471
Standby letters of credit [Member]	'	'
Loss Contingencies [Line Items]	'	'
Total financial instruments with off-balance sheet risk	146,689	135,761
Commercial letters of credit [Member]	'	'
Loss Contingencies [Line Items]	'	'
Total financial instruments with off-balance sheet risk	26,025	13,621
Unused commitments to extend credit [Member]	'	'
Loss Contingencies [Line Items]	'	'
Total financial instruments with off-balance sheet risk	$4,390,764	$4,127,089

Commitments_and_Contingencies_3

Commitments and Contingencies - Schedule for Unfunded Commitments (Details) (Reserve for Off-balance Sheet Activities [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Reserve for Off-balance Sheet Activities [Member]	'	'	'	'
Movement in Valuation Allowances and Reserves [Roll Forward]	'	'	'	'
Balance, beginning of period	$4,749	$4,593	$4,384	$5,662
Provision (benefit)	273	64	638	-1,005
Balance, end of period	$5,022	$4,657	$5,022	$4,657