Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Error Corrections and Prior Period Adjustments

The effects of correcting the immaterial errors in the Consolidated Balance Sheets, Consolidated Statements of Income and Consolidated Statements of Cash Flows are summarized in the following tables:



	December 31, 2015
(In thousands)	As Reported		As Revised
Consolidated Balance Sheets
Cash and due from banks	$	251,258	$	199,693
Accrued interest receivable and other assets ⁽¹⁾	328,993		343,856
Accrued expenses and other liabilities	267,576		233,581
Retained earnings	1,317,559		1,315,948

(1)

The amount recorded as revised includes the impact of a $1.1 million reclassification of debt issuance cost from accrued interest receivable and other assets into long-term debt. The reclassification was made in accordance with the Company's adoption of ASU No. 2015-03, Interest-Imputation of Interest (Subtopic 835-30) - Simplifying the Presentation of Debt Issuance Costs, and is not considered part of the error correction.



	Year ended December 31, 2015
(In thousands, except per share data)	As Reported		As Revised
Consolidated Statements of Income
Deposit service fees	$	136,578	$	135,057
Other income	23,573		23,326
Technology and equipment	80,026		80,813
Income tax expense	93,976		93,032
Net income	206,340		204,729
Earnings per common share:
Basic	$	2.17	$	2.15
Diluted	2.15		2.13

HSA Segment:
Net income	$	39,173	$	37,443



	December 31, 2015						December 31, 2014
(In thousands)	As Reported			As Revised			As Reported			As Revised
Consolidated Statements of Cash Flows
Net (increase) in accrued interest receivable and other assets ⁽¹⁾	$	(49,899	)	$	(44,334	)	$	(24,502	)	$	(2,552	)
Net increase in accrued expenses and other liabilities ⁽¹⁾	35,336			33,478			9,213			6,601

(1)

An additional line item, net decrease (increase) in derivative contract assets net of liabilities, was added to the Consolidated Statements of Cash Flows to detail the net change in derivative balances subject to offsetting. The update removed $6.5 million and $49.2 million in net increases in derivative contract assets net of liabilities from the net (increase) in accrued interest receivable and other assets and net increase in accrued expenses and other liabilities line items for the years ended December 31, 2015 and December 31, 2014 respectively.

Property, Plant and Equipment

Premises and equipment are carried at cost, less accumulated depreciation. Depreciation of premises and equipment is computed on a straight-line basis over the estimated useful lives of the assets, as follows:



Building and Improvements	5	-	40	years
Leasehold improvements	5	-	20	years (or term or lease, if shorter)
Fixtures and equipment	5	-	10	years
Data processing and software	3	-	7	years

A summary of premises and equipment follows:



	At December 31,
(In thousands)	2016			2015
Land	$	12,595		$	12,899
Buildings and improvements	90,778			94,686
Leasehold improvements	83,995			79,917
Fixtures and equipment	76,146			73,686
Data processing and software	220,002			195,308
Total premises and equipment	483,516			456,496
Less: Accumulated depreciation and amortization	(346,103		)	(327,070		)
Premises and equipment, net	$	137,413		$	129,426

Schedule of Prospective Adoption of New Accounting Pronouncements

The following table identifies ASUs applicable to the Company that have been issued by the FASB but are not yet effective:



ASU	Description	Effective Date and Financial Statement Impact
ASU No. 2016-15 - Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments.	The Update addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice. The Update addresses the following eight issues: Debt prepayment or debt extinguishment costs; settlement of zero-coupon debt instruments or other debt instruments with coupon interest rates that are insignificant in relation to the effective interest rate of the borrowing; contingent consideration payments made after a business combination; proceeds from the settlement of insurance claims; proceeds from the settlement of corporate-owned life insurance policies, including bank-owned life insurance policies; distributions received from equity method investees; beneficial interests in securitization transactions; and separately identifiable cash flows and application of the predominance principle.	The Company intends to adopt the Update for the first quarter of 2019. Adoption is not anticipated to have a material impact on the Company's financial statements.
ASU No. 2016-13 - Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.	Current GAAP requires an "incurred loss" methodology for recognizing credit losses that delays recognition until it is probable a loss has been incurred. Both financial institutions and users of their financial statements expressed concern that current GAAP restricts the ability to record credit losses that are expected, but do not yet meet the "probable" threshold. The main objective of this Update is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. To achieve this objective, the amendments in this Update replace the incurred loss impairment methodology in current GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to determine credit loss estimates.	The Change from an "incurred loss" method to an "expected loss" method represents a fundamental shift from existing GAAP, and may result in material changes to the Company's accounting for credit losses on financial instruments. The Company is evaluating the effect that this ASU will have on its financial statements and related disclosures. The ASU will be effective for the Company as of January 1, 2020.
ASU No. 2016-09, Compensation - Stock Compensation (Topic 718) - Improvements to Employee Share Based Payment Accounting.	The Update impacts the accounting for employee share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. In addition, the amendments in this Update eliminates the guidance in Topic 718 that was indefinitely deferred shortly after the issuance of FASB Statement No. 123 (revised 2004), Share-Based Payment.	The Company intends to adopt the Update for the first quarter of 2017. Adoption is not anticipated to have a material impact on the Company's financial statements.



ASU	Description	Effective Date and Financial Statement Impact
ASU No. 2016-06, Derivatives and Hedging (Topic 815) - Contingent Put and Call Options in Debt Instruments.	The Update clarifies the requirements for assessing whether contingent call (put) options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts. The Update requires the assessment of embedded call (put) options solely in accordance with the four-step decision sequence.	The Company intends to adopt the Update for the first quarter of 2017. Adoption is not anticipated to have a material impact on the Company's financial statements.
ASU No. 2016-02, Leases (Topic 842).	The Update introduces a lessee model that brings most leases on the balance sheet. The Update also aligns certain of the underlying principles of the new lessor model with those in ASC Topic 606 "Revenue from Contracts with Customers," the FASB’s new revenue recognition standard (e.g., evaluating how collectability should be considered and determining when profit can be recognized). Furthermore, the Update addresses other concerns including the elimination of the required use of bright-line tests for determining lease classification. Lessors are required to provide additional transparency into the exposure to the changes in value of their residual assets and how they manage that exposure.	The Company intends to adopt the Update for the first quarter of 2019. The Company expects the Update will have a significant effect on the Company's financial statements. While the Company is continuing to assess the effect of adoption, management currently believes the most significant changes relate to the recognition of new right of use assets and lease liabilities on the Company's balance sheet for operating leases.
ASU No. 2016-01, Financial Instruments—Overall (Subtopic 825-10) - Recognition and Measurement of Financial Assets and Financial Liabilities.	Equity investments not accounted for under the equity method or those that do not result in consolidation of the investee are to be measured at fair value with changes in the fair value recognized through net income. Entities are to present separately in other comprehensive income, the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when an election to measure the liability at fair value in accordance with the fair value option for financial instruments has been made. Also, the requirement to disclose the method(s) and significant assumptions used to estimate the fair value for financial instruments measured at amortized cost on the balance sheet has been eliminated.	The Company intends to adopt the Update for the first quarter of 2018. Adoption is not anticipated to have a material impact on the Company's financial statements.
ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606)	A single comprehensive model has been established 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, and clarify and converge revenue recognition principles under GAAP and International Financial Reporting Standards. The 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; and (v) recognize revenue when each performance obligation is satisfied. One of the most significant potential impacts relates to less prescriptive derecognition requirements on the sale of owned real estate properties. An entity may elect either a full retrospective or a modified retrospective application. ASU No. 2015-14 - Revenue from Contracts with Customers (Topic 606), defers the effective date to annual and interim periods beginning after December 15, 2017. During 2016, the FASB issued amendments to this standard (ASC Updates 2016-08, 2016-10, 2016-11 and 2016-20). The Updates provide further clarification to the standard.	The Company intends to adopt the Update for the first quarter of 2018. The Company's revenue is comprised of net interest income on financial assets and financial liabilities, and non-interest income. While the Company is continuing to assess the effect of adoption, management currently believes the Update may require the Company to change how certain trust and investment management fees within non-interest income are recognized. Management does not expect those changes to have a significant impact on the Company's financial statements. Management continues to evaluate the Update's impact on other components of non-interest income.