Sandy Spring Bancorp (SASR) 10-Q 7 May 21 2021 Q1 Quarterly report Financial data

Cover

Cover - shares	3 Months Ended
	Mar. 31, 2021	May 05, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	0-19065
Entity Registrant Name	SANDY SPRING BANCORP, INC.
Entity Incorporation State Country Code	MD
Entity Tax Identification Number	52-1532952
Entity Address Address Line1	17801 Georgia Avenue
Entity Address City Or Town	Olney
Entity Address State Or Province	MD
Entity Address Postal Zip Code	20832
City Area Code	301
Local Phone Number	774-6400
Security 12b Title	Common Stock, par value $1.00 per share
Trading Symbol	SASR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock Shares Outstanding (in shares)		47,268,656
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Central Index Key	0000824410
Current Fiscal Year End Date	--12-31

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF CONDITION - UNAUDITED - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets:
Cash and due from banks	$ 100,739	$ 93,651
Federal funds sold	285	291
Interest-bearing deposits with banks	127,597	203,061
Cash and cash equivalents	228,621	297,003
Residential mortgage loans held for sale (at fair value)	84,930	78,294
Proceeds from sales of investment available-for-sale	1,427,880	1,348,021
Equity securities	44,847	65,760
Total loans	10,446,866	10,400,509
Less: allowance for credit losses	(130,361)	(165,367)
Net loans	10,316,505	10,235,142
Premises and equipment, net	55,361	57,720
Other real estate owned	1,354	1,455
Accrued interest receivable	44,559	46,431
Goodwill	370,223	370,223
Other intangible assets, net	30,824	32,521
Other assets	268,262	265,859
Total assets	12,873,366	12,798,429
Liabilities:
Noninterest-bearing deposits	3,770,852	3,325,547
Interest-bearing deposits	6,906,900	6,707,522
Total deposits	10,677,752	10,033,069
Securities sold under retail repurchase agreements and federal funds purchased	189,318	543,157
Advances from FHLB	100,000	379,075
Subordinated debt	227,044	227,088
Total borrowings	516,362	1,149,320
Accrued interest payable and other liabilities	167,558	146,085
Total liabilities	11,361,672	11,328,474
Stockholders' equity:
Common stock	47,187	47,057
Additional paid in capital	849,606	846,922
Retained earnings	617,553	557,271
Accumulated other comprehensive income/ (loss)	(2,652)	18,705
Total stockholders' equity	1,511,694	1,469,955
Total liabilities and stockholders' equity	$ 12,873,366	$ 12,798,429

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CONDITION - UNAUDITED - (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	47,187,389	47,056,777
Common stock, shares outstanding (in shares)	47,187,389	47,056,777

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Interest income:
Interest and fees on loans	$ 107,428	$ 75,882
Interest on loans held for sale	537	291
Interest on deposits with banks	46	180
Interest and dividends on investment securities:
Taxable	3,899	6,132
Tax-advantaged	2,351	1,372
Interest on federal funds sold	0	1
Total interest income	114,261	83,858
Interest expense:
Interest on deposits	4,830	13,518
Interest on retail repurchase agreements and federal funds purchased	53	580
Interest on advances from FHLB	2,276	3,145
Interest on subordinated debt	2,502	2,281
Total interest expense	9,661	19,524
Net interest income	104,600	64,334
Provision/ (credit) for credit losses	(34,708)	24,469
Net interest income after provision/ (credit) for credit losses	139,308	39,865
Non-interest income:
Investment securities gains	58	169
Insurance agency commissions	2,153	2,129
Income from bank owned life insurance	680	645
Other income	3,706	1,653
Total non-interest income	28,866	18,168
Non-interest expense:
Salaries and employee benefits	36,652	28,053
Occupancy expense of premises	5,487	4,581
Equipment expense	3,222	2,751
Marketing	1,212	1,189
Outside data services	2,283	1,582
FDIC insurance	1,492	482
Amortization of intangible assets	1,697	600
Merger and acquisition expense	45	1,454
Professional fees and services	1,731	1,826
Other expenses	14,352	5,228
Total non-interest expense	68,173	47,746
Income before income tax expense	100,001	10,287
Income tax expense	24,537	300
Net income	$ 75,464	$ 9,987
Per share information:
Basic net income per common share (in dollars per share)	$ 1.59	$ 0.29
Diluted net income per common share (in dollars per share)	1.58	0.28
Dividends declared per share (in dollars per share)	$ 0.32	$ 0.30
Service charges on deposit accounts
Non-interest income:
Fees and commissions, mortgage banking and servicing	$ 1,852	$ 2,253
Mortgage banking activities
Non-interest income:
Fees and commissions, mortgage banking and servicing	10,169	3,033
Wealth management income
Non-interest income:
Fees and commissions, mortgage banking and servicing	8,730	6,966
Bank card fees
Non-interest income:
Fees and commissions, mortgage banking and servicing	$ 1,518	$ 1,320

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 75,464	$ 9,987
Investments available-for-sale:
Net change in unrealized gains/ (losses) on investments available-for-sale	(28,855)	14,263
Related income tax expense/ (benefit)	7,377	(3,624)
Net investment gains reclassified into earnings	(58)	(169)
Related income tax expense	15	42
Net effect on other comprehensive income/ (loss)	(21,521)	10,512
Defined benefit pension plan:
Net change of unrealized loss	227	219
Related income tax benefit	(63)	(55)
Net effect on other comprehensive income/ (loss)	164	164
Total other comprehensive income/ (loss)	(21,357)	10,676
Comprehensive income	$ 54,107	$ 20,663

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - UNAUDITED - USD ($) $ in Thousands	Total	Revision of Prior Period, Accounting Standards Update, Adjustment	Common Stock	Additional Paid-In Capital	Retained Earnings	Retained EarningsRevision of Prior Period, Accounting Standards Update, Adjustment	Accumulated Other Comprehensive Income/ (Loss)
Balance at beginning of period at Dec. 31, 2019	$ 1,132,974	$ (2,223)	$ 34,970	$ 586,622	$ 515,714	$ (2,223)	$ (4,332)
Net income	9,987				9,987
Other comprehensive loss, net of tax	10,676						10,676
Total other comprehensive income	20,663
Common stock dividends	(10,544)				(10,544)
Stock compensation expense	754			754
Stock option plan	122		6	116
Employee stock purchase plan	290		9	281
Common stock repurchase	(25,702)		(820)	(24,882)
Balance at end of period at Mar. 31, 2020	1,116,334		34,165	562,891	512,934		6,344
Balance at beginning of period at Dec. 31, 2020	1,469,955		47,057	846,922	557,271		18,705
Net income	75,464				75,464
Other comprehensive loss, net of tax	(21,357)						(21,357)
Total other comprehensive income	54,107
Common stock dividends	(15,182)				(15,182)
Stock compensation expense	947			947
Stock option plan	1,531		102	1,429
Employee stock purchase plan	541		20	521
Restricted stock, net	(205)		8	(213)
Balance at end of period at Mar. 31, 2021	$ 1,511,694		$ 47,187	$ 849,606	$ 617,553		$ (2,652)

CONDENSED CONSOLIDATED STATEM_6

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - UNAUDITED - (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Stockholders' Equity [Abstract]
Common stock dividends (in dollars per share)	$ 0.32	$ 0.30
Stock option plan (in shares)	102,365	6,013
Employee stock purchase plan (in shares)	20,417	8,617
Restricted stock (in shares)	7,830
Stock repurchased and retired (in shares)		820,328

CONDENSED CONSOLIDATED STATEM_7

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities:
Net income	$ 75,464	$ 9,987
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	3,462	3,427
Provision/ (credit) for credit losses	(34,708)	24,469
Share based compensation expense	947	754
Deferred income tax/ (benefit)	9,125	(5,205)
Origination of loans held for sale	(536,747)	(217,560)
Proceeds from sales of loans held for sale	540,736	208,409
Gains on sales of loans held for sale	(10,625)	(4,262)
Losses on sale of other real estate owned	0	9
Investment securities gains	(58)	(169)
Tax benefit associated with share based compensation	426	28
Net (increase)/ decrease in accrued interest receivable	1,872	(588)
Net increase in other assets	(9,461)	(19,317)
Net increase/ (decrease) accrued expenses and other liabilities	(12,786)	7,976
Other, net	370	5,055
Net cash provided by operating activities	28,017	13,013
Investing activities:
Sales/ (purchases) of equity securities	20,913
Sales/ (purchases) of equity securities		(10,582)
Purchases of investments available-for-sale	(280,942)	(241,682)
Proceeds from sales of investment available-for-sale	100,822	13,104
Proceeds from maturities, calls and principal payments of investments available-for-sale	99,668	127,111
Net increase in loans	(37,247)	(17,760)
Proceeds from the sales of other real estate owned	0	27
Cash paid for the acquisition of business activity of RPJ, net of cash acquired	0	(26,925)
Sales of/ (expenditures for) premises and equipment	420
Sales of/ (expenditures for) premises and equipment		(696)
Net cash used in investing activities	(96,366)	(157,403)
Financing activities:
Net increase in deposits	646,196	153,555
Net decrease in in retail repurchase agreements and federal funds purchased	(353,839)	(88,300)
Proceeds from FHLB advances	0	250,000
Repayment of FHLB advances	(279,075)	(9,716)
Retirement of subordinated debt	0	(10,310)
Proceeds from issuance of common stock	2,072	412
Stock tendered for payment of withholding taxes	(205)	0
Repurchase of common stock	0	(25,702)
Dividends paid	(15,182)	(10,544)
Net cash provided by/ (used in) financing activities	(33)	259,395
Net increase/ (decrease) in cash and cash equivalents	(68,382)	115,005
Cash and cash equivalents at beginning of period	297,003	146,103
Cash and cash equivalents at end of period	228,621	261,108
Supplemental disclosures:
Interest payments	11,533	17,055
Income tax payments, net of refunds of $1,834 in 2021	$ 22,276	$ 0

CONDENSED CONSOLIDATED STATEM_8

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - Parenthetical $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Statement of Cash Flows [Abstract]
Income tax refunds	$ 1,834

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
SIGNIFICANT ACCOUNTING POLICIES	SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Sandy Spring Bancorp, Inc. ("Sandy Spring" or, together with its subsidiaries, the "Company"), a Maryland corporation, is the bank holding company for Sandy Spring Bank (the “Bank”). Independent and community-oriented, Sandy Spring Bank offers a broad range of commercial banking, retail banking, mortgage services and trust services throughout central Maryland, Northern Virginia, and the greater Washington, D.C. market. Sandy Spring Bank also offers a comprehensive menu of insurance and wealth management services through its subsidiaries, Sandy Spring Insurance Corporation (“Sandy Spring Insurance”), West Financial Services, Inc. (“West Financial”) and Rembert Pendleton Jackson (“RPJ”). Basis of Presentation The accounting and reporting policies of the Company conform to accounting principles generally accepted in the United States of America (“GAAP”), prevailing practices within the financial services industry for interim financial information and Rule 10-01 of Regulation S-X. Accordingly, the interim financial statements do not include all of the information and notes required for complete financial statements. The following summary of significant accounting policies of the Company is presented to assist the reader in understanding the financial and other data presented in this report. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for any future periods or for the year ending December 31, 2021. In the opinion of management, all adjustments necessary for a fair presentation of the results of the interim periods have been included. Certain reclassifications have been made to prior period amounts, as necessary, to conform to the current period presentation. The Company has evaluated subsequent events through the date of the issuance of its financial statements. These statements should be read in conjunction with the financial statements and accompanying notes included in the Company’s 2020 Annual Report on Form 10-K as filed with the Securities and Exchange Commission (“SEC”) on February 19, 2021. There have been no significant changes to any of the Company’s accounting policies as disclosed in the 2020 Annual Report on Form 10-K. Principles of Consolidation The unaudited Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiary, Sandy Spring Bank, and its subsidiaries, Sandy Spring Insurance, West Financial and RPJ. Consolidation has resulted in the elimination of all intercompany accounts and transactions. See Note 18 for more information on the Company’s segments and consolidation. Use of Estimates The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements, in addition to affecting the reported amounts of revenues earned and expenses incurred during the reporting period. Actual results could differ from those estimates. Estimates that could change significantly relate to the provision for credit losses and the related allowance, potential impairment of goodwill or other intangible assets, valuation of investment securities and the determination of whether available-for-sale debt securities with fair values less than amortized costs are impaired and require an allowance for credit losses, valuation of other real estate owned, valuation of share based compensation, the assessment that a liability should be recognized with respect to any matters under litigation, the calculation of current and deferred income taxes, and the actuarial projections related to pension expense and the related liability. Cash Flows For purposes of reporting cash flows, cash and cash equivalents include cash and due from banks, federal funds sold and interest-bearing deposits with banks (items with stated original maturity of three months or less). Revenue from Contracts with Customers The Company’s revenue includes net interest income on financial instruments and non-interest income. Specific categories of revenue are presented in the Condensed Consolidated Statements of Income. Most of the Company’s revenue is not within the scope of Accounting Standard Codification (“ASC”) 606 – Revenue from Contracts with Customers. For revenue within the scope of ASC 606, the Company provides services to customers and has related performance obligations. The revenue from such services is recognized upon satisfaction of all contractual performance obligations. The following discusses key revenue streams within the scope of revenue recognition guidance. Wealth Management Income West Financial and RPJ provide comprehensive investment management and financial planning services. Wealth management income is comprised of income for providing trust, estate and investment management services. Trust services include acting as a trustee for corporate or personal trusts. Investment management services include investment management, record-keeping and reporting of security portfolios. Fees for these services are recognized based on a contractually-agreed fixed percentage applied to net assets under management at the end of each reporting period. The Company does not charge/recognize any performance-based fees. Insurance Agency Commissions Sandy Spring Insurance, a subsidiary of the Bank, performs the function of an insurance intermediary by introducing the policyholder and insurer and is compensated by a commission fee for placement of an insurance policy. Sandy Spring Insurance does not provide any captive management services or any claim handling services. Commission fees are set as a percentage of the premium for the insurance policy for which Sandy Spring Insurance is a producer. Sandy Spring Insurance recognizes revenue when the insurance policy has been contractually agreed to by the insurer and policyholder (at transaction date). Service Charges on Deposit Accounts Service charges on deposit accounts are earned on depository accounts for consumer and commercial account holders and include fees for account and overdraft services. Account services include fees for event-driven services and periodic account maintenance activities. An obligation for event-driven services is satisfied at the time of the event when service is delivered and revenue recognized as earned. Obligation for maintenance activities is satisfied over the course of each month and revenue is recognized at month end. The overdraft services obligation is satisfied at the time of the overdraft and revenue is recognized as earned. Loan Financing Receivables The Company’s financing receivables consist primarily of loans that are stated at their principal balance outstanding, net of any unearned income, acquisition fair value marks and deferred loan origination fees and costs. Interest income on loans is accrued at the contractual rate based on the principal balance outstanding. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the related loan yield using the interest method. Loans are considered past due or delinquent when the principal or interest due in accordance with the contractual terms of the loan agreement or any portion thereof remains unpaid after the due date of the scheduled payment. Immaterial shortfalls in payment amounts do not necessarily result in a loan being considered delinquent or past due. If any payments are past due and subsequent payments are resumed without payment of the delinquent amount, the loan shall continue to be considered past due. Whenever any loan is reported delinquent on a principal or interest payment or portion thereof, the amount reported as delinquent is the outstanding principal balance of the loan. Loans, except for consumer installment loans, are placed into non-accrual status when any portion of the loan principal or interest becomes 90 days past due. Management may determine that certain circumstances warrant earlier discontinuance of interest accruals on specific loans if an evaluation of other relevant factors (such as bankruptcy, interruption of cash flows, etc.) indicates collection of amounts contractually due is unlikely. These loans are considered, collectively, to be non-performing loans. Consumer installment loans that are not secured by real estate are not placed on non-accrual, but are charged down to their net realizable value when they are four months past due. Loans designated as non-accrual have all previously accrued but unpaid interest reversed. Interest income is not recognized on non-accrual loans. All payments received on non-accrual loans are applied using a cost-recovery method to reduce the outstanding principal balance until the loan returns to accrual status. Loans may be returned to accrual status when all principal and interest amounts contractually due are brought current and future payments are reasonably assured. Loans considered to be TDRs are loans that have their terms restructured (e.g., interest rates, loan maturity date, payment and amortization period, etc.) in circumstances that provide payment relief to a borrower experiencing financial difficulty. All restructured collateral-dependent loans are individually assessed for allowance for credit losses and may either be in accruing or non-accruing status. Non-accruing restructured loans may return to accruing status provided doubt has been removed concerning the collectability of principal and interest as evidenced by a sufficient period of payment performance in accordance with the restructured terms. Loans may be removed from the restructured category if the borrower is no longer experiencing financial difficulty, a re-underwriting event took place, and the revised loan terms of the subsequent restructuring agreement are considered to be consistent with terms that can be obtained in the market for loans with comparable credit risk. Allowance for Credit Losses The allowance for credit losses (“allowance” or “ACL”) represents an amount which, in management's judgment, is adequate to absorb the lifetime expected losses that may be sustained on outstanding loans at the balance sheet date based on the evaluation of the size and current risk characteristics of the loan portfolio, past events, current conditions, reasonable and supportable forecasts of future economic conditions and prepayment experience. The allowance is measured and recorded upon the initial recognition of a financial asset. The allowance is reduced by charge-offs, net of recoveries of previous losses, and is increased or decreased by a provision or credit for credit losses, which is recorded as a current period expense. Determination of the adequacy of the allowance is inherently complex and requires the use of significant and highly subjective estimates. The reasonableness of the allowance is reviewed periodically by the Risk Committee of the Board of Directors and formally approved quarterly by that same committee of the Board. The Company’s methodology for estimating the allowance includes: (1) a collective quantified reserve that reflects the Company’s historical default and loss experience adjusted for expected economic conditions throughout a reasonable and supportable period and the Company’s prepayment and curtailment rates; (2) collective qualitative factors that consider concentrations of the loan portfolio, expected changes to the economic forecasts, large relationships, early delinquencies, and factors related to credit administration, including, among others, loan-to-value ratios, borrowers’ risk rating and credit score migrations; and (3) individual allowances on collateral-dependent loans where borrowers are experiencing financial difficulty or when the Company determines that the foreclosure is probable. The Company excludes accrued interest from the measurement of the allowance as the Company has a non-accrual policy to reverse any accrued, uncollected interest income as loans are moved to non-accrual status. Loans are pooled into segments based on the similar risk characteristics of the underlying borrowers, in addition to consideration of collateral type, industry and business purpose of the loans. Portfolio segments used to estimate the allowance are the same as portfolio segments used for general credit risk management purposes. Refer to Note 4 for more details on the Company’s portfolio segments. The Company applies two calculation methodologies to estimate the collective quantified component of the allowance: discounted cash flows method and weighted average remaining life method. Allowance estimates on commercial acquisition, development and construction (“AD&C”) and residential construction segments are based on the weighted average remaining life method. Allowance estimates on all other portfolio segments are based on the discounted cash flows method. Segments utilizing the discounted cash flows method are further sub-segmented into risk level pools, determined either by risk rating for commercial loans or Beacon Scores ranges for residential and consumer loans. To better manage risk and reasonably determine the sufficiency of reserves, this segregation allows the Company to monitor the allowance component applicable to higher risk loans separate from the remainder of the portfolio. Collective calculation methodologies utilize the Company’s historical default and loss experience adjusted for future economic forecasts. The reasonable and supportable forecast period represents a two-year economic outlook for the applicable economic variables. Following the end of the reasonable and supportable forecast period expected losses revert back to the historical mean over the next two years on a straight-line basis. Economic variables that have the most significant impact on the allowance include: unemployment rate, house price index and number of business bankruptcies. Contractual loan level cash flows within the discounted cash flows methodology are adjusted for the Company’s historical prepayment and curtailment rate experience. The individual reserve assessment is applied to collateral dependent loans where borrowers are experiencing financial difficulty or when the Company determines that a foreclosure is probable. The determination of the fair value of the collateral depends on whether a repayment of the loan is expected to be from the sale or the operation of the collateral. When a repayment is expected from the operation of the collateral, the Company uses the present value of expected cash flows from the operation of the collateral as the fair value. When the repayment of the loan is expected from the sale of the collateral the fair value of the collateral is based on an observable market price or the collateral’s appraised value, less estimated costs to sell. Third party appraisals used in the individual reserve assessment are conducted at least annually with underlying assumptions that are reviewed by management. Third party appraisals may be obtained on a more frequent basis if deemed necessary. Internal evaluations of collateral value are conducted quarterly to ensure any further deterioration of the collateral value is recognized on a timely basis. During the individual reserve assessment, management also considers the potential future changes in the value of the collateral over the remainder of the loan’s remaining life. The Company may receive updated appraisals which contradict the preliminary determination of fair value used to establish an individual allowance on a loan. In these instances the individual allowance is adjusted to reflect the Company’s evaluation of the updated appraised fair value. In the event a loss was previously confirmed and the loan was charged down to the estimated fair value based on a previous appraisal, the balance of partially charged-off loans are not subsequently increased, but could be further decreased depending on the direction of the change in fair value. Payments on fully or partially charged-off loans are accounted for under the cost-recovery method. Under this method, all payments received are applied on a cash basis to reduce the entire outstanding principal balance, then to recognize a recovery of all previously charged-off amounts before any interest income may be recognized. Based on the individual reserve assessment, if the Company determines that the fair value of the collateral is less than the amortized cost basis of the loan, an individual allowance will be established measured as the difference between the fair value of the collateral (less costs to sell) and the amortized cost basis of the loan. Once a loss has been confirmed, the loan is charged-down to its estimated fair value. Large groups of smaller non-accrual homogeneous loans are not individually evaluated for allowance and include residential permanent and construction mortgages and consumer installment loans. These portfolios are reserved for on a collective basis using historical loss rates of similar loans over the weighted average life of each pool. The Company reviews its unfunded commitments to determine if they are unconditionally cancellable by the Company. If the unfunded commitment is determined to not be unconditionally cancellable by the Company, a reserve for unfunded commitments is established. The reserve for unfunded commitments considers both the likelihood that the funding will occur and an estimate of expected credit losses over the life of the commitment. Management believes it uses relevant information available to make determinations about the allowance and that it has established the existing allowance in accordance with GAAP. However, the determination of the allowance requires significant judgment, and estimates of expected lifetime losses in the loan portfolio can vary significantly from the amounts actually observed. While management uses available information to recognize expected losses, future additions to the allowance may be necessary based on changes in the loans comprising the portfolio, changes in the current and forecasted economic conditions, changes to the interest rate environment which may directly impact prepayment and curtailment rate assumptions, and changes in the financial condition of borrowers. Acquired Loans Loans acquired in connection with acquisitions are recorded at their acquisition-date fair value. The allowance for credit losses related to the acquired loan portfolio is not carried over. Acquired loans are classified into two categories based on the credit risk characteristics of the underlying borrowers as either purchased credit deteriorated (“PCD”) loans, or loans with no evidence of credit deterioration (“non-PCD”). PCD loans are defined as a loan or pool of loans that have experienced more-than-insignificant credit deterioration since the origination date. The Company uses a combination of individual and pooled review approaches to determine if acquired loans are PCD. At acquisition, the Company considers a number of factors to determine if an acquired loan or pool of loans has experienced more-than-insignificant credit deterioration. These factors include: • loans classified as non-accrual, • loans with risk rating of special mention or worse (using the Company's risk rating scale), • loans with multiple risk rating downgrades since origination, • loans with evidence of being 60 days or more past due, • loans previously modified in a troubled debt restructuring, • loans that received an interest only or payment deferral modification, and • loans in industries that show evidence of additional risk due to economic conditions. The initial allowance related to PCD loans that share similar risk characteristics is established using a pooled approach. The Company uses either a discounted cash flow or weighted average remaining life method to determine the required level of the allowance. PCD loans that were classified as non-accrual as of the acquisition date and are collateral dependent are assessed for allowance on an individual basis. For PCD loans, an initial allowance is established on the acquisition date and added to the fair value of the loan to arrive at acquisition date amortized cost. Accordingly, no provision for credit losses is recognized on PCD loans at the acquisition date. Subsequent to the acquisition date, the initial allowance on PCD loans will increase or decrease based on future evaluations, with changes recognized in the provision for credit losses. Non-PCD loans are pooled into segments together with originated loans that share similar risk characteristics and have an allowance established on the acquisition date, which is recognized in the current period provision for credit losses. Determining the fair value of the acquired loans involves estimating the principal and interest payment cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. Management considers a number of factors in evaluating the acquisition-date fair value including the remaining life, interest rate profile, market interest rate environment, payment schedules, risk ratings, probability of default and loss given default, and estimated prepayment rates. For PCD loans, the non-credit discount or premium is allocated to individual loans as determined by the difference between the loan’s unpaid principal balance and amortized cost basis. The non-credit premium or discount is recognized into interest income on a level yield basis over the remaining expected life of the loan. For non-PCD loans, the fair value discount or premium is allocated to individual loans and recognized into interest income on a level yield basis over the remaining expected life of the loan. Leases The Company determines if an arrangement is a lease at inception. All of the Company’s leases are currently classified as operating leases and are included in other assets and other liabilities on the Company’s Condensed Consolidated Statements of Condition. Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term, and lease liabilities represent the Company’s obligation to make lease payments arising from the lease arrangements. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of the expected future lease payments over the remaining lease term. In determining the present value of future lease payments, the Company uses its incremental borrowing rate based on the information available at the lease commencement date. The operating ROU assets are adjusted for any lease payments made at or before the lease commencement date, initial direct costs, any lease incentives received and, for acquired leases, any favorable or unfavorable fair value adjustments. The present value of the lease liability may include the impact of options to extend or terminate the lease when it is reasonably certain that the Company will exercise such options provided in the lease terms. Lease expense is recognized on a straight-line basis over the expected lease term. Lease agreements that include lease and non-lease components, such as common area maintenance charges, are accounted for separately. Pending Accounting Pronouncements In March 2020, FASB released Accounting Standards Update (“ASU”) 2020-04 - Reference Rate Reform (Topic 848) , which provides optional guidance to ease the accounting burden in accounting for, or recognizing the effects from, reference rate reform on financial reporting. The new standard is a result of LIBOR likely being discontinued as an available benchmark rate. The standard is elective and provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, or other transactions that reference LIBOR, or another reference rate expected to be discontinued. The amendments in the update are effective for all entities between March 12, 2020 and December 31, 2022. The Company has established a cross-functional working group to guide the Company’s transition from LIBOR and has begun efforts to transition to alternative rates consistent with industry timelines. The Company has identified its products that utilize LIBOR and has implemented enhanced fallback language to facilitate the transition to alternative reference rates. The Company is evaluating existing platforms and systems and preparing to offer new rates.

ACQUISITION OF REVERE BANK

ACQUISITION OF REVERE BANK	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
ACQUISITION OF REVERE BANK	ACQUISITION OF REVERE BANK On April 1, 2020 (“Acquisition Date”), the Company completed the acquisition of Revere Bank (“Revere”), a Maryland chartered commercial bank, in accordance with the definitive agreement that was entered on September 23, 2019 by and among the Company, the Bank and Revere. In connection with the completion of the merger, former Revere shareholders received 1.05 shares of Sandy Spring common stock for each share of Revere common stock they held. Based on the $22.64 per share closing price of Sandy Spring common stock on March 31, 2020, and including the fair value of options converted or cashed-out, the total transaction value was approximately $293.0 million. Upon completion of the acquisition, Sandy Spring shareholders owned approximately 74 percent of the combined company, and former Revere shareholders owned approximately 26 percent. As of March 31, 2020, Revere, headquartered in Rockville, MD, had more than $2.8 billion in assets and operated 11 full-service community banking offices throughout the Washington D.C. metropolitan region. The acquisition of Revere was accounted for as a business combination using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed, and consideration paid were recorded at estimated fair values on the Acquisition Date. The amount of goodwill recognized as of the Acquisition Date was approximately $0.8 million. After immaterial adjustments recorded during the fourth quarter of 2020, the amount of goodwill recognized as of December 31, 2021 was $0.5 million. Management's final review of assets acquired and liabilities assumed did not result in additional adjustments during the first quarter of 2021, and goodwill was determined to be final as of March 31, 2021. The goodwill is not deductible for tax purposes. The consideration paid for Revere’s common equity and outstanding stock options and the provisional fair values of acquired identifiable assets and assumed identifiable liabilities as of March 31, 2021 were as follows: (Dollars in thousands, except per share data) March 31, 2021 Purchase price: Fair value of common shares issued (12,768,949 shares) based on Sandy Spring's share price of $22.64 $ 289,089 Fair value of Revere stock options converted to Sandy Spring stock options 3,611 Cash paid for cashed-out Revere stock options 291 Cash for fractional shares 11 Total purchase price $ 293,002 Identifiable assets: Cash and cash equivalents $ 80,744 Investments available-for-sale 180,752 Loans 2,502,244 Premises and equipment 3,443 Accrued interest receivable 7,651 Core deposit intangible asset 18,360 Other assets 53,162 Total identifiable assets $ 2,846,356 Identifiable liabilities: Deposits $ 2,322,422 Borrowings 205,514 Other liabilities 25,933 Total identifiable liabilities $ 2,553,869 Fair value of net assets acquired including identifiable intangible assets 292,487 Goodwill $ 515

INVESTMENTS

INVESTMENTS	3 Months Ended
	Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract]
INVESTMENTS	INVESTMENTS Investments available-for-sale The amortized cost and estimated fair values of investments available-for-sale at the dates indicated are presented in the following table: March 31, 2021 December 31, 2020 (In thousands) Amortized Gross Gross Estimated Amortized Gross Gross Estimated U.S. treasuries and government agencies $ 47,641 $ 447 $ (2) $ 48,086 $ 42,750 $ 549 $ (2) $ 43,297 State and municipal 362,815 7,926 (4,709) 366,032 377,108 13,470 (211) 390,367 Mortgage-backed and asset-backed 1,001,475 15,222 (10,518) 1,006,179 881,201 24,078 (847) 904,432 Corporate debt 7,000 583 — 7,583 9,100 825 — 9,925 Total investments available-for-sale $ 1,418,931 $ 24,178 $ (15,229) $ 1,427,880 $ 1,310,159 $ 38,922 $ (1,060) $ 1,348,021 Any unrealized losses in the U.S. treasuries and government agencies, state and municipal, mortgage-backed and asset-backed investment securities at March 31, 2021 are due to changes in interest rates and not credit-related events. As such, no allowance for credit losses is required at March 31, 2021. Unrealized losses on investment securities are expected to recover over time as these securities approach maturity. The Company does not intend to sell, nor is it more likely than not it will be required to sell, these securities and has sufficient liquidity to hold these securities for an adequate period of time, which may be maturity, to allow for any anticipated recovery in fair value. The mortgage-backed securities portfolio at March 31, 2021 is composed entirely of either the most senior tranches of GNMA, FNMA or FHLMC collateralized mortgage obligations ($318.5 million), GNMA, FNMA or FHLMC mortgage-backed securities ($626.0 million) or SBA asset-backed securities ($61.7 million). Gross unrealized losses and fair value by length of time that the individual available-for-sale securities have been in an unrealized loss position at the dates indicated are presented in the following tables: March 31, 2021 Number Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. treasuries and government agencies 1 $ 4,972 $ 2 $ — $ — $ 4,972 $ 2 State and municipal 43 115,530 4,709 — — 115,530 4,709 Mortgage-backed and asset-backed 46 373,235 10,509 4,968 9 378,203 10,518 Total 90 $ 493,737 $ 15,220 $ 4,968 $ 9 $ 498,705 $ 15,229 December 31, 2020 Number Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. treasuries and government agencies 2 $ 25,369 $ 2 $ — $ — $ 25,369 $ 2 State and municipal 8 22,753 211 — — 22,753 211 Mortgage-backed and asset-backed 24 44,746 154 76,879 693 121,625 847 Total 34 $ 92,868 $ 367 $ 76,879 $ 693 $ 169,747 $ 1,060 The estimated fair values and amortized costs of debt securities available-for-sale by contractual maturity at the dates indicated are provided in the following table. The Company has allocated mortgage-backed securities into the four maturity groupings reflected in the following tables using the expected average life of the individual securities based on statistics provided by independent third party industry sources. Expected maturities will differ from contractual maturities as borrowers may have the right to prepay obligations with or without prepayment penalties. March 31, 2021 December 31, 2020 (In thousands) Fair Value Amortized Cost Fair Value Amortized Cost U.S. treasuries and government agencies: One year or less $ 36,904 $ 36,744 $ 33,963 $ 33,833 One to five years 11,182 10,897 9,334 8,917 Five to ten years — — — — After ten years — — — — State and municipal: One year or less 13,175 13,098 16,581 16,458 One to five years 38,077 36,965 44,910 43,857 Five to ten years 49,417 47,569 59,059 56,130 After ten years 265,363 265,183 269,817 260,663 Mortgage-backed and asset-backed: One year or less 1,923 1,905 1 1 One to five years 20,180 19,822 21,637 21,229 Five to ten years 67,401 66,718 74,142 72,481 After ten years 916,675 913,030 808,652 787,490 Corporate debt: One year or less — — — — One to five years — — 2,318 2,100 Five to ten years 7,583 7,000 7,607 7,000 After ten years — — — — Total available-for-sale debt securities $ 1,427,880 $ 1,418,931 $ 1,348,021 $ 1,310,159 At March 31, 2021 and December 31, 2020, investments available-for-sale with a book value of $454.0 million and $465.7 million, respectively, were pledged as collateral for certain government deposits and for other purposes as required or permitted by law. The outstanding balance of no single issuer, except for U.S. Agencies securities, exceeded ten percent of stockholders' equity at March 31, 2021 and December 31, 2020. Equity securities Other equity securities at the dates indicated are presented in the following table: (In thousands) March 31, 2021 December 31, 2020 Federal Reserve Bank stock $ 34,028 $ 38,650 Federal Home Loan Bank of Atlanta stock 10,142 26,433 Marketable equity securities 677 677 Total equity securities $ 44,847 $ 65,760

LOANS

LOANS	3 Months Ended
	Mar. 31, 2021
Receivables [Abstract]
LOANS	LOANS Outstanding loan balances at March 31, 2021 and December 31, 2020, are net of unearned income, including net deferred loan fees of $30.3 million and $24.5 million, respectively. Net deferred loan fees at March 31, 2021 and December 31, 2020, includes $27.0 million and $21.2 million, respectively, related to the loans originated under the Paycheck Protection Program (“PPP”). The loan portfolio segment balances at the dates indicated are presented in the following table: (In thousands) March 31, 2021 December 31, 2020 Commercial real estate: Commercial investor real estate $ 3,652,418 $ 3,634,720 Commercial owner-occupied real estate 1,644,848 1,642,216 Commercial AD&C 1,051,013 1,050,973 Commercial business 2,411,109 2,267,548 Total commercial loans 8,759,388 8,595,457 Residential real estate: Residential mortgage 1,022,546 1,105,179 Residential construction 171,028 182,619 Consumer 493,904 517,254 Total residential and consumer loans 1,687,478 1,805,052 Total loans $ 10,446,866 $ 10,400,509 Portfolio Segments The Company currently manages its credit products and the respective exposure to credit losses (credit risk) by the following specific portfolio segments (classes) which are levels at which the Company develops and documents its systematic methodology to determine the allowance for credit losses attributable to each respective portfolio segment. These segments are: • Commercial investor real estate loans - Commercial investor real estate loans consist of loans secured by nonowner-occupied properties where an established banking relationship exists and involves investment properties for warehouse, retail, and office space with a history of occupancy and cash flow. This commercial investor real estate category contains mortgage loans to the developers and owners of commercial real estate where the borrower intends to operate or sell the property at a profit and use the income stream or proceeds from the sale(s) to repay the loan. • Commercial owner-occupied real estate loans - Commercial owner-occupied real estate loans consist of commercial mortgage loans secured by owner occupied properties where an established banking relationship exists and involves a variety of property types to conduct the borrower’s operations. The decision to extend a loan is based upon the borrower’s financial health and the ability of the borrower and the business to repay. The primary source of repayment for this type of loan is the cash flow from the operations of the business. • Commercial acquisition, development and construction loans - Commercial acquisition, development and construction loans are intended to finance the construction of commercial properties and include loans for the acquisition and development of land. Construction loans represent a higher degree of risk than permanent real estate loans and may be affected by a variety of additional factors such as the borrower’s ability to control costs and adhere to time schedules and the risk that constructed units may not be absorbed by the market within the anticipated time frame or at the anticipated price. The loan commitment on these loans often includes an interest reserve that allows the lender to periodically advance loan funds to pay interest charges on the outstanding balance of the loan. • Commercial business loans - Commercial loans are made to provide funds for equipment and general corporate needs. Repayment of a loan primarily comes from the funds obtained from the operation of the borrower’s business. Commercial loans also include lines of credit that are utilized to finance a borrower’s short-term credit needs and/or to finance a percentage of eligible receivables and inventory. Loans issued under the PPP are also included in this category, a substantial portion of which are expected to be forgiven by the Small Business Administration pursuant to the CARES Act. • Residential mortgage loans - The residential mortgage loans category contains permanent mortgage loans principally to consumers secured by residential real estate. Residential real estate loans are evaluated for the adequacy of repayment sources at the time of approval, based upon measures including credit scores, debt-to-income ratios, and collateral values. Loans may be either conforming or non-conforming. • Residential construction loans - The Company makes residential construction loans generally to provide interim financing on residential property during the construction period. Borrowers are typically individuals who will ultimately occupy the single-family dwelling. Loan funds are disbursed periodically as pre-specified stages of completion are attained based upon site inspections . • Consumer loans - This category of loans includes primarily home equity loans and lines, installment loans, personal lines of credit, and other loans. The home equity category consists mainly of revolving lines of credit to consumers which are secured by residential real estate. These loans are typically secured with second mortgages on the homes. Other consumer loans include installment loans used by customers to purchase automobiles, boats and recreational vehicles.

CREDIT QUALITY ASSESSMENT

CREDIT QUALITY ASSESSMENT	3 Months Ended
	Mar. 31, 2021
Credit Loss [Abstract]
CREDIT QUALITY ASSESSMENT	CREDIT QUALITY ASSESSMENT Allowance for Credit Losses Summary information on the allowance for credit loss activity for the period indicated is provided in the following table: Three Months Ended March 31, (In thousands) 2021 2020 Balance at beginning of period $ 165,367 $ 56,132 Initial allowance on PCD loans at adoption of ASC 326 — 2,762 Transition impact of adopting ASC 326 — 2,983 Provision for credit losses (34,708) 24,469 Loan charge-offs (743) (654) Loan recoveries 445 108 Net charge-offs (298) (546) Balance at period end $ 130,361 $ 85,800 The following table provides summary information regarding collateral dependent loans individually evaluated for credit loss at the dates indicated: (In thousands) March 31, 2021 December 31, 2020 Collateral dependent loans individually evaluated for credit loss with an allowance $ 32,241 $ 20,717 Collateral dependent loans individually evaluated for credit loss without an allowance 49,757 77,001 Total individually evaluated collateral dependent loans $ 81,998 $ 97,718 Allowance for credit losses related to loans evaluated individually $ 13,101 $ 11,405 Allowance for credit losses related to loans evaluated collectively 117,260 153,962 Total allowance for credit losses $ 130,361 $ 165,367 The following tables provide information on the activity in the allowance for credit losses by the respective loan portfolio segment for the period indicated: For the Three Months Ended March 31, 2021 Commercial Real Estate Residential Real Estate (Dollars in thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Balance at beginning of period $ 57,404 $ 20,061 $ 22,157 $ 46,806 $ 11,295 $ 1,502 $ 6,142 $ 165,367 Provision for credit losses (8,981) (5,594) 760 (14,343) (4,018) (849) (1,683) (34,708) Charge-offs — — — (650) — — (93) (743) Recoveries 27 — — 16 270 — 132 445 Net recoveries (charge-offs) 27 — — (634) 270 — 39 (298) Balance at end of period $ 48,450 $ 14,467 $ 22,917 $ 31,829 $ 7,547 $ 653 $ 4,498 $ 130,361 Total loans $ 3,652,418 $ 1,644,848 $ 1,051,013 $ 2,411,109 $ 1,022,546 $ 171,028 $ 493,904 $ 10,446,866 Allowance for credit losses to total loans ratio 1.33 % 0.88 % 2.18 % 1.32 % 0.74 % 0.38 % 0.91 % 1.25 % Balance of loans individually evaluated for credit loss $ 42,776 $ 8,316 $ 14,975 $ 13,831 $ 1,737 $ — $ 363 $ 81,998 Allowance related to loans evaluated individually $ 2,988 $ — $ 603 $ 9,510 $ — $ — $ — $ 13,101 Individual allowance to loans evaluated individually ratio 6.99 % — % 4.03 % 68.76 % — % — % — % 15.98 % Balance of loans collectively evaluated for credit loss $ 3,609,642 $ 1,636,532 $ 1,036,038 $ 2,397,278 $ 1,020,809 $ 171,028 $ 493,541 $ 10,364,868 Allowance related to loans evaluated collectively $ 45,462 $ 14,467 $ 22,314 $ 22,319 $ 7,547 $ 653 $ 4,498 $ 117,260 Collective allowance to loans evaluated collectively ratio 1.26 % 0.88 % 2.15 % 0.93 % 0.74 % 0.38 % 0.91 % 1.13 % For the Year Ended December 31, 2020 Commercial Real Estate Residential Real Estate (Dollars in thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Balance at beginning of period $ 18,407 $ 6,884 $ 7,590 $ 11,395 $ 8,803 $ 967 $ 2,086 $ 56,132 Initial allowance on PCD loans at adoption of ASC 326 1,114 — — 1,549 — — 99 2,762 Transition impact of adopting ASC 326 (3,125) 387 2,576 2,988 (388) (275) 820 2,983 Initial allowance on acquired Revere PCD loans 7,973 2,782 1,248 6,289 243 6 87 18,628 Provision for credit losses 33,431 10,008 10,743 24,374 3,016 798 3,299 85,669 Charge-offs (411) — — (491) (484) — (433) (1,819) Recoveries 15 — — 702 105 6 184 1,012 Net recoveries (charge-offs) (396) — — 211 (379) 6 (249) (807) Balance at end of period $ 57,404 $ 20,061 $ 22,157 $ 46,806 $ 11,295 $ 1,502 $ 6,142 $ 165,367 Total loans $ 3,634,720 $ 1,642,216 $ 1,050,973 $ 2,267,548 $ 1,105,179 $ 182,619 $ 517,254 $ 10,400,509 Allowance for credit losses to total loans ratio 1.58 % 1.22 % 2.11 % 2.06 % 1.02 % 0.82 % 1.19 % 1.59 % Balance of loans individually evaluated for credit loss $ 45,227 $ 11,561 $ 15,044 $ 23,648 $ 1,874 $ — $ 364 $ 97,718 Allowance related to loans evaluated individually $ 1,273 $ — $ 603 $ 9,529 $ — $ — $ — $ 11,405 Individual allowance to loans evaluated individually ratio 2.81 % — % 4.01 % 40.30 % — % — % — % 11.67 % Balance of loans collectively evaluated for credit loss $ 3,589,493 $ 1,630,655 $ 1,035,929 $ 2,243,900 $ 1,103,305 $ 182,619 $ 516,890 $ 10,302,791 Allowance related to loans evaluated collectively $ 56,131 $ 20,061 $ 21,554 $ 37,277 $ 11,295 $ 1,502 $ 6,142 $ 153,962 Collective allowance to loans evaluated collectively ratio 1.56 % 1.23 % 2.08 % 1.66 % 1.02 % 0.82 % 1.19 % 1.49 % The following tables present collateral dependent loans individually evaluated for credit loss with the associated allowances for credit losses by the applicable portfolio segment and for the periods indicated: March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Loans individually evaluated for credit loss with an allowance: Non-accruing $ 17,686 $ — $ 1,446 $ 9,730 $ — $ — $ — $ 28,862 Restructured accruing — — — 573 — — — 573 Restructured non-accruing 336 — — 2,470 — — — 2,806 Balance $ 18,022 $ — $ 1,446 $ 12,773 $ — $ — $ — $ 32,241 Allowance $ 2,988 $ — $ 603 $ 9,510 $ — $ — $ — $ 13,101 Loans individually evaluated for credit loss without an allowance: Non-accruing $ 24,754 $ 6,125 $ 13,529 $ 318 $ — $ — $ — $ 44,726 Restructured accruing — — — 111 1,587 — — 1,698 Restructured non-accruing — 2,191 — 629 150 — 363 3,333 Balance $ 24,754 $ 8,316 $ 13,529 $ 1,058 $ 1,737 $ — $ 363 $ 49,757 Total individually evaluated loans: Non-accruing $ 42,440 $ 6,125 $ 14,975 $ 10,048 $ — $ — $ — $ 73,588 Restructured accruing — — — 684 1,587 — — 2,271 Restructured non-accruing 336 2,191 — 3,099 150 — 363 6,139 Balance $ 42,776 $ 8,316 $ 14,975 $ 13,831 $ 1,737 $ — $ 363 $ 81,998 Total unpaid contractual principal balance $ 47,547 $ 10,306 $ 16,157 $ 16,088 $ 2,814 $ — $ 364 $ 93,276 December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Loans individually evaluated for credit loss with an allowance: Non-accruing $ 4,913 $ — $ 1,328 $ 11,178 $ — $ — $ — $ 17,419 Restructured accruing — — — 589 — — — 589 Restructured non-accruing 699 — — 2,010 — — — 2,709 Balance $ 5,612 $ — $ 1,328 $ 13,777 $ — $ — $ — $ 20,717 Allowance $ 1,273 $ — $ 603 $ 9,529 $ — $ — $ — $ 11,405 Loans individually evaluated for credit loss without an allowance: Non-accruing $ 39,615 $ 9,315 $ 13,716 $ 9,118 $ — $ — $ — $ 71,764 Restructured accruing — — — 126 1,602 — — 1,728 Restructured non-accruing — 2,246 — 627 272 — 364 3,509 Balance $ 39,615 $ 11,561 $ 13,716 $ 9,871 $ 1,874 $ — $ 364 $ 77,001 Total individually evaluated loans: Non-accruing $ 44,528 $ 9,315 $ 15,044 $ 20,296 $ — $ — $ — $ 89,183 Restructured accruing — — — 715 1,602 — — 2,317 Restructured non-accruing 699 2,246 — 2,637 272 — 364 6,218 Balance $ 45,227 $ 11,561 $ 15,044 $ 23,648 $ 1,874 $ — $ 364 $ 97,718 Total unpaid contractual principal balance $ 49,920 $ 15,309 $ 16,040 $ 30,958 $ 3,225 $ — $ 364 $ 115,816 The following tables present average principal balance of total non-accrual loans and contractual interest due on non-accrual loans for the periods indicated below: For the Three Months Ended March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Average non-accrual loans for the period $ 44,002 $ 9,939 $ 15,010 $ 18,040 $ 9,903 $ — $ 7,289 $ 104,183 Contractual interest income due on non- accrual loans during the period $ 649 $ 185 $ 256 $ 428 $ 110 $ — $ 104 $ 1,732 For the Year Ended December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Average non-accrual loans for the period $ 26,849 $ 6,605 $ 4,267 $ 16,532 $ 11,634 $ — $ 6,675 $ 72,562 Contractual interest income due on non- accrual loans during the period $ 6,547 $ 2,741 $ 4,505 $ 2,858 $ 918 $ — $ 732 $ 18,301 There was no interest income recognized on non-accrual loans during the three months ended March 31, 2021. See Note 1 for additional information on the Company's policies for non-accrual loans. Loans designated as non-accrual have all previously accrued but unpaid interest reversed from interest income. During the three months ended March 31, 2021 new loans placed on non-accrual status totaled $0.4 million and the related amount of reversed uncollected accrued interest was insignificant. Credit Quality The following section provides information on the credit quality of the loan portfolio for the periods indicated below: For the Three Months Ended March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Analysis of non-accrual loan activity: Balance at beginning of period $ 45,227 $ 11,561 $ 15,044 $ 22,933 $ 10,212 $ — $ 7,384 $ 112,361 Loans placed on non-accrual — — — 84 140 — 197 421 Non-accrual balances transferred to OREO — — — — — — — — Non-accrual balances charged-off — — — (650) — — (49) (699) Net payments or draws (2,451) (3,245) (69) (9,220) (759) — (284) (16,028) Non-accrual loans brought current — — — — — — (55) (55) Balance at end of period $ 42,776 $ 8,316 $ 14,975 $ 13,147 $ 9,593 $ — $ 7,193 $ 96,000 For the Year Ended December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Analysis of non-accrual loan activity: Balance at beginning of period $ 8,437 $ 4,148 $ 829 $ 8,450 $ 12,661 $ — $ 4,107 $ 38,632 PCD loans designated as non-accrual (1) 9,544 — — 2,539 8 — 993 13,084 Loans placed on non-accrual 37,882 8,572 15,844 17,442 1,485 — 4,061 85,286 Non-accrual balances transferred to OREO — — — — (70) — — (70) Non-accrual balances charged-off (411) — — (446) (416) — (121) (1,394) Net payments or draws (10,225) (1,059) (1,629) (4,169) (2,598) — (1,521) (21,201) Non-accrual loans brought current — (100) — (883) (858) — (135) (1,976) Balance at end of period $ 45,227 $ 11,561 $ 15,044 $ 22,933 $ 10,212 $ — $ 7,384 $ 112,361 (1) Upon the adoption of the CECL standard, the Company transitioned from closed pool level accounting for PCI loans during the first quarter of 2020. Non-accrual loans are determined based on the individual loan level and aggregated for reporting. March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Performing loans: Current $ 3,587,859 $ 1,633,446 $ 1,031,055 $ 2,392,818 $ 997,837 $ 170,365 $ 483,280 $ 10,296,660 30-59 days 17,870 3,086 4,983 3,983 9,593 601 1,809 41,925 60-89 days 3,913 — — 446 3,538 62 1,622 9,581 Total performing loans 3,609,642 1,636,532 1,036,038 2,397,247 1,010,968 171,028 486,711 10,348,166 Non-performing loans: Non-accrual loans 42,776 8,316 14,975 13,147 9,593 — 7,193 96,000 Loans greater than 90 days past due — — — 31 398 — — 429 Restructured loans — — — 684 1,587 — — 2,271 Total non-performing loans 42,776 8,316 14,975 13,862 11,578 — 7,193 98,700 Total loans $ 3,652,418 $ 1,644,848 $ 1,051,013 $ 2,411,109 $ 1,022,546 $ 171,028 $ 493,904 $ 10,446,866 December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Performing loans: Current $ 3,571,184 $ 1,624,265 $ 1,033,057 $ 2,238,617 $ 1,073,963 $ 182,557 $ 502,548 $ 10,226,191 30-59 days 14,046 6,390 29 4,859 16,213 — 5,275 46,812 60-89 days 4,130 — 2,843 263 2,709 62 2,047 12,054 Total performing loans 3,589,360 1,630,655 1,035,929 2,243,739 1,092,885 182,619 509,870 10,285,057 Non-performing loans: Non-accrual loans 45,227 11,561 15,044 22,933 10,212 — 7,384 112,361 Loans greater than 90 days past due 133 — — 161 480 — — 774 Restructured loans — — — 715 1,602 — — 2,317 Total non-performing loans 45,360 11,561 15,044 23,809 12,294 — 7,384 115,452 Total loans $ 3,634,720 $ 1,642,216 $ 1,050,973 $ 2,267,548 $ 1,105,179 $ 182,619 $ 517,254 $ 10,400,509 The credit quality indicators for commercial loans are developed through review of individual borrowers on an ongoing basis. Each borrower is evaluated at least annually with more frequent evaluation of more severely criticized loans. The indicators represent the rating for loans as of the date presented is based on the most recent credit review performed. These credit quality indicators are defined as follows: Pass - A pass rated credit is not adversely classified because it does not display any of the characteristics for adverse classification. Special mention – A special mention credit has potential weaknesses that deserve management’s close attention. If uncorrected, such weaknesses may result in deterioration of the repayment prospects or collateral position at some future date. Special mention assets are not adversely classified and do not warrant adverse classification. Substandard – A substandard loan is inadequately protected by the current net worth and payment capacity of the obligor or of the collateral pledged, if any. Loans classified as substandard generally have a well-defined weakness, or weaknesses, that jeopardize the liquidation of the debt. These loans are characterized by the distinct possibility of loss if the deficiencies are not corrected. Doubtful – A loan that is classified as doubtful has all the weaknesses inherent in a loan classified as substandard with added characteristics that the weaknesses make collection or liquidation in full highly questionable and improbable, on the basis of currently existing facts, conditions and values. Loss – Loans classified as a loss are considered uncollectible and of such little value that their continuing to be carried as a loan is not warranted. This classification is not necessarily equivalent to no potential for recovery or salvage value, but rather that it is not appropriate to defer a full write-off even though partial recovery may be effected in the future. The following table provides information about credit quality indicators by the year of origination as of March 31, 2021: March 31, 2021 Term Loans by Origination Year Revolving (In thousands) 2021 2020 2019 2018 2017 Prior Loans Total Commercial Investor R/E: Pass $ 194,465 $ 881,973 $ 707,450 $ 452,909 $ 429,839 $ 876,375 $ 28,844 $ 3,571,855 Special Mention 10,000 527 1,993 2,640 701 2,646 — 18,507 Substandard 279 437 6,175 13,555 28,149 13,461 — 62,056 Doubtful — — — — — — — — Total $ 204,744 $ 882,937 $ 715,618 $ 469,104 $ 458,689 $ 892,482 $ 28,844 $ 3,652,418 Commercial Owner-Occupied R/E: Pass $ 47,661 $ 287,070 $ 375,951 $ 222,539 $ 188,795 $ 485,151 $ 4,793 $ 1,611,960 Special Mention — 1,871 4,327 3,586 4,698 5,279 — 19,761 Substandard — 1,269 4,316 2,031 447 5,064 — 13,127 Doubtful — — — — — — — — Total $ 47,661 $ 290,210 $ 384,594 $ 228,156 $ 193,940 $ 495,494 $ 4,793 $ 1,644,848 Commercial AD&C: Pass $ 174,120 $ 373,158 $ 244,751 $ 110,557 $ 47,150 $ — $ 80,645 $ 1,030,381 Special Mention 639 1,073 — — — — — 1,712 Substandard 1,102 455 891 — 13,629 2,843 — 18,920 Doubtful — — — — — — — — Total $ 175,861 $ 374,686 $ 245,642 $ 110,557 $ 60,779 $ 2,843 $ 80,645 $ 1,051,013 Commercial Business: Pass $ 459,815 $ 1,059,494 $ 179,214 $ 129,096 $ 77,302 $ 71,681 $ 396,258 $ 2,372,860 Special Mention — 2,043 8,793 1,063 1,214 845 3,792 17,750 Substandard 225 4,785 3,494 3,338 857 6,019 1,781 20,499 Doubtful — — — — — — — — Total $ 460,040 $ 1,066,322 $ 191,501 $ 133,497 $ 79,373 $ 78,545 $ 401,831 $ 2,411,109 Residential Mortgage: Beacon score: 660-850 $ 43,362 $ 209,544 $ 66,700 $ 113,850 $ 153,972 $ 336,256 $ — $ 923,684 600-659 745 4,962 9,539 8,498 8,044 25,851 — 57,639 540-599 — 1,445 1,181 5,063 1,930 14,187 — 23,806 less than 540 497 2,318 1,545 3,182 1,118 8,757 — 17,417 Total $ 44,604 $ 218,269 $ 78,965 $ 130,593 $ 165,064 $ 385,051 $ — $ 1,022,546 Residential Construction: Beacon score: 660-850 $ 27,097 $ 101,290 $ 21,059 $ 14,166 $ 1,248 $ 1,738 $ 364 $ 166,962 600-659 — — 2,743 — — 369 — 3,112 540-599 — — — — — — — — less than 540 — 954 — — — — — 954 Total $ 27,097 $ 102,244 $ 23,802 $ 14,166 $ 1,248 $ 2,107 $ 364 $ 171,028 Consumer: Beacon score: 660-850 $ 1,054 $ 2,200 $ 4,263 $ 4,213 $ 1,567 $ 27,406 $ 400,050 $ 440,753 600-659 247 265 1,138 484 259 6,092 17,590 26,075 540-599 — 105 564 272 270 3,425 6,938 11,574 less than 540 103 729 151 569 765 3,277 9,908 15,502 Total $ 1,404 $ 3,299 $ 6,116 $ 5,538 $ 2,861 $ 40,200 $ 434,486 $ 493,904 Total loans $ 961,411 $ 2,937,967 $ 1,646,238 $ 1,091,611 $ 961,954 $ 1,896,722 $ 950,963 $ 10,446,866 The following table provides information about credit quality indicators by the year of origination as of December 31, 2020: December 31, 2020 Term Loans by Origination Year Revolving (In thousands) 2020 2019 2018 2017 2016 Prior Loans Total Commercial Investor R/E: Pass $ 910,426 $ 763,214 $ 448,406 $ 448,698 $ 469,077 $ 498,384 $ 33,531 $ 3,571,736 Special Mention 11,044 — 4,879 833 269 27 — 17,052 Substandard 589 4,245 13,649 20,619 673 6,157 — 45,932 Doubtful — — — — — — — — Total $ 922,059 $ 767,459 $ 466,934 $ 470,150 $ 470,019 $ 504,568 $ 33,531 $ 3,634,720 Commercial Owner-Occupied R/E: Pass $ 285,310 $ 385,058 $ 234,578 $ 192,634 $ 204,925 $ 306,840 $ 1,664 $ 1,611,009 Special Mention 2,290 — 3,027 4,742 134 4,079 — 14,272 Substandard 1,610 4,335 2,065 465 219 8,009 — 16,703 Doubtful — — — — — 232 — 232 Total $ 289,210 $ 389,393 $ 239,670 $ 197,841 $ 205,278 $ 319,160 $ 1,664 $ 1,642,216 Commercial AD&C: Pass $ 485,631 $ 261,537 $ 149,703 $ 50,192 $ 89 $ 2,357 $ 80,764 $ 1,030,273 Special Mention 1,711 — — — — — — 1,711 Substandard 1,439 891 — 13,816 2,843 — — 18,989 Doubtful — — — — — — — — Total $ 488,781 $ 262,428 $ 149,703 $ 64,008 $ 2,932 $ 2,357 $ 80,764 $ 1,050,973 Commercial Business: Pass $ 1,244,822 $ 208,682 $ 138,861 $ 86,830 $ 34,498 $ 81,760 $ 433,016 $ 2,228,469 Special Mention 1,929 1,382 1,119 708 309 621 4,319 10,387 Substandard 2,914 4,564 3,519 1,631 2,745 3,456 1,829 20,658 Doubtful 106 995 849 36 1,284 1,852 2,912 8,034 Total $ 1,249,771 $ 215,623 $ 144,348 $ 89,205 $ 38,836 $ 87,689 $ 442,076 $ 2,267,548 Residential Mortgage: Beacon score: 660-850 $ 229,033 $ 74,054 $ 138,824 $ 172,493 $ 129,701 $ 251,065 $ — $ 995,170 600-659 4,824 7,706 10,763 11,719 8,173 21,424 — 64,609 540-599 350 1,238 5,219 2,608 4,791 10,167 — 24,373 less than 540 2,702 2,108 3,576 2,150 892 9,599 — 21,027 Total $ 236,909 $ 85,106 $ 158,382 $ 188,970 $ 143,557 $ 292,255 $ — $ 1,105,179 Residential Construction: Beacon score: 660-850 $ 112,604 $ 44,647 $ 14,543 $ 2,805 $ 1,693 $ — $ 172 $ 176,464 600-659 1,743 3,189 — — — — — 4,932 540-599 — — — — 369 — — 369 less than 540 854 — — — — — — 854 Total $ 115,201 $ 47,836 $ 14,543 $ 2,805 $ 2,062 $ — $ 172 $ 182,619 Consumer: Beacon score: 660-850 $ 2,575 $ 4,609 $ 5,112 $ 2,110 $ 2,614 $ 24,444 $ 417,737 $ 459,201 600-659 374 445 334 428 467 5,401 21,052 28,501 540-599 89 1,216 294 339 601 3,926 6,153 12,618 less than 540 751 160 525 785 532 2,826 11,355 16,934 Total $ 3,789 $ 6,430 $ 6,265 $ 3,662 $ 4,214 $ 36,597 $ 456,297 $ 517,254 Total loans $ 3,305,720 $ 1,774,275 $ 1,179,845 $ 1,016,641 $ 866,898 $ 1,242,626 $ 1,014,504 $ 10,400,509 The following table provides the amounts of the restructured loans at the date of restructuring for specific segments of the loan portfolio during the period indicated: For the Three Months Ended March 31, 2021 Commercial Real Estate (In thousands) Commercial Commercial Commercial Commercial All Total Troubled debt restructurings: Restructured accruing $ — $ — $ — $ — $ — $ — Restructured non-accruing — — — 512 — 512 Balance $ — $ — $ — $ 512 $ — $ 512 Individual allowance $ — $ — $ — $ 332 $ — $ 332 Restructured and subsequently defaulted $ — $ — $ — $ — $ — $ — For the Year Ended December 31, 2020 Commercial Real Estate (In thousands) Commercial Commercial Commercial Commercial All Total Troubled debt restructurings: Restructured accruing $ — $ — $ — $ 380 $ 549 $ 929 Restructured non-accruing 723 930 — 1,951 — 3,604 Balance $ 723 $ 930 $ — $ 2,331 $ 549 $ 4,533 Individual allowance $ 65 $ — $ — $ 955 $ — $ 1,020 Restructured and subsequently defaulted $ — $ — $ — $ — $ — $ — During the three months ended March 31, 2021, the Company restructured $0.5 million in loans that were designated as TDRs. TDR loans are subject to periodic credit reviews to determine the necessity and appropriateness of an individual credit loss allowance based on the collectability of the recorded investment in the TDR loan. Loans restructured as TDRs during the three months ended March 31, 2021 had individual reserves of $0.3 million. For the year ended December 31, 2020, the Company restructured $4.5 million in loans. Loans restructured as TDRs during 2020 had individual reserves of $1.0 million at December 31, 2020. During both the three months ended March 31, 2021 and for the year ended December 31, 2020 TDR modifications consisted principally of interest rate concessions, and did not result in the reduction of the recorded investment in the associated loan balances. The commitments to lend additional funds on loans that have been restructured at March 31, 2021 and December 31, 2020 were not significant. Other Real Estate Owned Other real estate owned ("OREO") totaled $1.4 million and $1.5 million at March 31, 2021 and December 31, 2020, respectively. There were no consumer mortgage loans secured by residential real estate property for which formal foreclosure proceedings were in process as of March 31, 2021.

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	GOODWILL AND OTHER INTANGIBLE ASSETS The gross carrying amounts and accumulated amortization of intangible assets and goodwill are presented at the dates indicated in the following table: March 31, 2021 Weighted December 31, 2020 Weighted (Dollars in thousands) Gross Accumulated Net Gross Accumulated Net Amortizing intangible assets: Core deposit intangibles $ 29,038 $ (9,169) $ 19,869 8.2 years $ 29,038 $ (7,969) $ 21,069 8.4 years Other identifiable intangibles 13,906 (2,951) 10,955 10.5 years 13,906 (2,454) 11,452 10.7 years Total amortizing intangible assets $ 42,944 $ (12,120) $ 30,824 $ 42,944 $ (10,423) $ 32,521 Goodwill $ 370,223 $ 370,223 $ 370,223 $ 370,223 The amount of goodwill by reportable segment is presented in the following table: (In thousands) Community Insurance Investment Total Balances at December 31, 2020 $ 331,688 $ 6,788 $ 31,747 $ 370,223 No Activity — — — — Balances at March 31, 2021 $ 331,688 $ 6,788 $ 31,747 $ 370,223 The following table presents the estimated future amortization expense for amortizing intangible assets within the years ending December 31: (In thousands) Amount Remaining 2021 $ 4,903 2022 5,844 2023 5,089 2024 4,333 2025 3,567 Thereafter 7,088 Total amortizing intangible assets $ 30,824

DEPOSITS

DEPOSITS	3 Months Ended
	Mar. 31, 2021
Deposits [Abstract]
DEPOSITS	DEPOSITS The following table presents the composition of deposits at the dates indicated: (In thousands) March 31, 2021 December 31, 2020 Noninterest-bearing deposits $ 3,770,852 $ 3,325,547 Interest-bearing deposits: Demand 1,395,209 1,292,164 Money market savings 3,371,400 3,339,645 Regular savings 465,125 418,051 Time deposits of less than $100,000 474,684 509,919 Time deposits greater than $100,000 and less than $250,000 774,668 670,717 Time deposits of $250,000 or more 425,814 477,026 Total interest-bearing deposits 6,906,900 6,707,522 Total deposits $ 10,677,752 $ 10,033,069

BORROWINGS

BORROWINGS	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
BORROWINGS	BORROWINGS Subordinated Debt On November 5, 2019, the Company completed an offering of $175.0 million aggregate principal amount Fixed to Floating Rate Subordinated Notes due in 2029. The notes bear a fixed interest rate of 4.25% per year through November 14, 2024. Beginning November 15, 2024, the interest rate will become a floating rate equal to three month LIBOR, or an alternative benchmark rate as determined pursuant to the terms of the indenture for the notes in the event LIBOR has been discontinued by November 15, 2024, plus 262 basis points through the remaining maturity or early redemption date of the notes. The interest will be paid in arrears semi-annually during the fixed rate period and quarterly during the floating rate period. The Company incurred $2.9 million of debt issuance costs which are being amortized through the contractual life of the debt. The entire amount of the subordinated debt is considered Tier 2 capital under current regulatory guidelines. In conjunction with the acquisition of WashingtonFirst Bankshares, Inc. ("WashingtonFirst"), the Company assumed $25.0 million in subordinated debt with an associated purchase premium at acquisition of $2.2 million. The premium is amortized over the contractual life of the obligation. The subordinated debt has a maturity of 10 years, maturing on October 15, 2025, and was non-callable through October 15, 2020. The subordinated debt held a fixed interest rate of 6.00% per annum through October 5, 2020 at which point the rate became variable at the three-month LIBOR plus 457 basis points payable quarterly. As of March 31, 2021, the effective variable rate was 4.81%. Under regulatory capital guidelines subordinated debt begins to phase out of Tier 2 capital qualification, on an annual straight-line basis, when there are five years remaining until the subordinated debt matures. The WashingtonFirst subordinated debt has less than five years but more than four years remaining until it matures, and therefore, as of March 31, 2021, $20.0 million of the subordinated debt is considered Tier 2 capital under current regulatory guidelines. In conjunction with the acquisition of Revere, the Company assumed $31.0 million in subordinated debt with an associated purchase premium at acquisition of $0.2 million, which will be amortized through the call date. The subordinated debt has a 10 year term, maturing on September 30, 2026, is non-callable until September 30, 2021, and currently bears a fixed interest rate of 5.625% per annum, payable semi-annually. Beginning on October 1, 2021, the interest rate resets quarterly to an amount equal to 3 month LIBOR plus 441 basis points. The entire amount of the subordinated debt is considered Tier 2 capital under current regulatory guidelines. The following table provides information on subordinated debt as of the date indicated: (In thousands) March 31, 2021 December 31, 2020 Fixed to floating rate sub debt, 4.25% $ 175,000 $ 175,000 WashingtonFirst sub debt, 4.81% 25,000 25,000 Revere fixed to floating rate sub debt, 5.625% 31,000 31,000 Total Sub debt 231,000 231,000 Less: Debt held as investments by Sandy Spring (3,000) (3,000) Add: Purchase accounting premium 1,552 1,669 Less: Debt issuance costs (2,508) (2,581) Long-term borrowings $ 227,044 $ 227,088 Other Borrowings At March 31, 2021 and December 31, 2020, the Company had $129.3 million and $153.2 million, respectively, of outstanding retail repurchase agreements. The Company had $60.0 million and $390.0 million of outstanding federal funds purchased at March 31, 2021 and December 31, 2020, respectively. At March 31, 2021, the Company did not have any borrowings outstanding of the $1.3 billion available to borrow under the Paycheck Protection Program Liquidity Facility ("PPPLF"). Amounts borrowed under the PPPLF are required to be repaid as PPP loans are repaid or forgiven. At March 31, 2021, the Company had an available line of credit with the FHLB under which its borrowings are limited to $3.0 billion based on pledged collateral at prevailing market interest rates, with $100.0 million borrowed against it at March 31, 2021. At December 31, 2020, lines of credit with the FHLB totaled $3.0 billion based on pledged collateral with $379.1 million borrowed against the line. During the three months ended March 31, 2021, the Company repaid $279.0 million of FHLB advances, resulting in a prepayment penalty of $9.1 million, which was recorded to other expense in the Condensed Consolidated Statements of Income. Under a blanket lien, the Company has pledged qualifying residential mortgage loans amounting to $897.8 million, commercial real estate loans amounting to $2.8 billion, home equity lines of credit (“HELOC”) amounting to $230.5 million, and multifamily loans amounting to $259.4 million at March 31, 2021, as collateral under the borrowing agreement with the FHLB. At December 31, 2020, the Company had pledged collateral of qualifying mortgage loans of $1.0 billion, commercial real estate loans of $2.8 billion, HELOC loans of $226.2 million, and multifamily loans of $237.6 million under the FHLB borrowing agreement. The Company also had secured lines of credit available from the Federal Reserve Bank and correspondent banks of $420.4 million and $276.2 million at March 31, 2021 and December 31, 2020, respectively, collateralized by loans, with no borrowings outstanding at the end of either period. In addition, the Company had unsecured lines of credit with correspondent

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2021
Stockholders' Equity Note [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS' EQUITYIn December 2020, the Company's board of directors authorized a stock repurchase plan that permits the repurchase of up to 2,350,000 shares of common stock. No shares of common stock have been repurchased under this plan. Under the previous stock repurchase plan that was approved in 2018 and expired in December 2020, the Company was authorized to repurchase up to 1,800,000 shares. During the first quarter of 2020, the Company repurchased and retired 820,328 common shares for the total cost of $25.7 million. Cumulatively under the previous plan, as of December 31, 2020, the Company repurchased and retired 1,488,519 shares of its common stock at an average price of $33.58 per share for a total cumulative cost of $50.0 million.

SHARE BASED COMPENSATION

SHARE BASED COMPENSATION	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
SHARE BASED COMPENSATION	SHARE BASED COMPENSATION At March 31, 2021, the Company had two share based compensation plans in existence, the 2005 Omnibus Stock Plan (“Omnibus Stock Plan”) and the 2015 Omnibus Incentive Plan (“Omnibus Incentive Plan”). The Omnibus Stock Plan expired during the second quarter of 2015 but has outstanding options that may still be exercised. The Omnibus Incentive Plan is described in the following paragraph. The Company’s Omnibus Incentive Plan was approved on May 6, 2015 and provides for the granting of incentive stock options, non-qualifying stock options, stock appreciation rights, restricted stock grants, restricted stock units and performance share units to selected directors and employees on a periodic basis at the discretion of the Company’s Board of Directors. The Omnibus Incentive Plan authorizes the issuance of up to 1,500,000 shares of common stock, of which 797,157 are available for issuance at March 31, 2021, has a term of 10 years, and is administered by a committee of at least three directors appointed by the Board of Directors. Options granted under the plan have an exercise price which may not be less than 100% of the fair market value of the common stock on the date of the grant and must be exercised within seven years or 10 years from the date of grant depending on the terms of the grant agreement. The exercise price of stock options must be paid for in full in cash or shares of common stock, or a combination of both. The board committee has the discretion when making a grant of stock options to impose restrictions on the shares to be purchased upon the exercise of such options. The Company generally issues authorized but previously unissued shares to satisfy option exercises. The dividend yield is based on estimated future dividend yields. The risk-free rate for periods within the contractual term of the share option is based on the U.S. Treasury yield curve in effect at the time of the grant. Expected volatilities are generally based on historical volatilities. The expected term of share options granted is generally derived from historical experience. Compensation expense is recognized on a straight-line basis over the vesting period of the respective stock option, restricted stock, restricted stock unit grant or performance share units. The Company recognized compensation expense of $0.9 million and $0.8 million, for the three months ended March 31, 2021 and 2020, respectively, related to the awards of stock options, restricted stock grants, restricted stock unit grants and performance share unit grants. There was no unrecognized compensation cost related to stock options as of March 31, 2021. The total of unrecognized compensation cost related to restricted stock awards, restricted stock unit grants, and performance share unit grants was approximately $11.8 million as of March 31, 2021. That cost is expected to be recognized over a weighted average period of approximately 2.70 years. During the three months ended March 31, 2021, the Company granted 119,329 restricted shares, restricted stock units and performance share units, of which 32,728 units are subject to achievement of certain performance conditions measured over a three-year performance period and 86,601 restricted shares or units are subject to a three year vesting schedule. The Company did not grant any stock options under the Omnibus Incentive Plan during the three months ended March 31, 2021. A summary of share option activity for the period indicated is reflected in the following table: Number Weighted Weighted Aggregate Balance at January 1, 2021 430,038 $ 14.97 3.0 years $ 6,828 Granted — $ — Exercised (102,365) $ 14.96 $ 2,381 Forfeited — $ — Expired — $ — Balance at March 31, 2021 327,673 $ 14.98 2.6 years $ 9,045 Exercisable at March 31, 2021 322,908 $ 14.63 2.6 years $ 9,017 A summary of the activity for the Company’s restricted stock, restricted stock units and performance share units for the period indicated is presented in the following table: Number Weighted Non-vested at January 1, 2021 391,683 $ 29.50 Granted 119,329 $ 40.70 Vested (13,669) $ 37.64 Forfeited/ cancelled (3,988) $ 34.86 Non-vested at March 31, 2021 493,355 $ 31.94

PENSION PLAN

PENSION PLAN	3 Months Ended
	Mar. 31, 2021
Retirement Benefits [Abstract]
PENSION PLAN	PENSION PLAN Defined Benefit Pension Plan The Company has a qualified, noncontributory, defined benefit pension plan (the “Plan”). Benefits after January 1, 2005, are based on the benefit earned as of December 31, 2004, plus benefits earned in future years of service based on the employee’s compensation during each such year. All benefit accruals for employees were frozen as of December 31, 2007 based on past service and thus salary increases and additional years of service after such date no longer affect the defined benefit provided by the Plan, although additional vesting may continue to occur. The Company's funding policy is to contribute amounts to the Plan sufficient to meet the minimum funding requirements of the Employee Retirement Income Security Act of 1974 (“ERISA”), as amended. In addition, the Company contributes additional amounts as it deems appropriate based on benefits attributed to service prior to the date of the Plan freeze. The Plan invests primarily in a diversified portfolio of managed fixed income and equity funds. The components of net periodic benefit cost for the periods indicated are presented in the following table: Three Months Ended March 31, (In thousands) 2021 2020 Interest cost on projected benefit obligation $ 318 $ 359 Expected return on plan assets (312) (456) Recognized net actuarial loss 227 219 Net periodic benefit cost $ 233 $ 122 The decision as to whether or not to make a plan contribution and the amount of any such contribution is dependent on a number of factors. Such factors include the investment performance of Plan assets in the current economy and, since the Plan is currently frozen, the remaining investment horizon of the Plan. After consideration of these factors, the Company has not made a contribution during the three months ended March 31, 2021. Management continues to monitor the funding level of the Plan and may make additional contributions as necessary during 2021.

NET INCOME PER COMMON SHARE

NET INCOME PER COMMON SHARE	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
NET INCOME PER COMMON SHARE	NET INCOME PER COMMON SHARE The calculation of net income per common share for the periods indicated is presented in the following table: Three Months Ended March 31, (Dollars and amounts in thousands, except per share data) 2021 2020 Net income $ 75,464 $ 9,987 Distributed and undistributed earnings allocated to (640) (68) Net income attributable to common shareholders $ 74,824 $ 9,919 Total weighted average outstanding shares 47,530 34,979 Less: Weighted average participating securities (411) (314) Basic weighted average common shares 47,119 34,665 Dilutive weighted average common stock equivalents 296 78 Diluted weighted average common shares 47,415 34,743 Basic net income per common share $ 1.59 $ 0.29 Diluted net income per common share $ 1.58 $ 0.28 Anti-dilutive shares 3 9

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME/ (LOSS)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE INCOME/ (LOSS)	ACCUMULATED OTHER COMPREHENSIVE INCOME/ (LOSS) Comprehensive income/ (loss) is defined as net income/ (loss) plus transactions and other occurrences that are the result of non-owner changes in equity. For Condensed Consolidated Financial Statements presented for the Company, non-owner changes in equity are comprised of unrealized gains or losses on investments available-for-sale and any minimum pension liability adjustments. The following table presents the activity in net accumulated other comprehensive income/ (loss) and the components of the activity for the periods indicated: (In thousands) Unrealized Gains Defined Benefit Total Balance at January 1, 2021 $ 28,175 $ (9,470) $ 18,705 Other comprehensive loss before reclassification, net of tax (21,478) — (21,478) Reclassifications from accumulated other comprehensive income, net of tax (43) 164 121 Current period change in other comprehensive income, net of tax (21,521) 164 (21,357) Balance at March 31, 2021 $ 6,654 $ (9,306) $ (2,652) (In thousands) Unrealized Gains/ Defined Benefit Total Balance at January 1, 2020 $ 4,000 $ (8,332) $ (4,332) Other comprehensive income before reclassification, net of tax 10,639 — 10,639 Reclassifications from accumulated other comprehensive income, net of tax (127) 164 37 Current period change in other comprehensive income, net of tax 10,512 164 10,676 Balance at March 31, 2020 $ 14,512 $ (8,168) $ 6,344 The following table provides the information on the reclassification adjustments out of accumulated other comprehensive income/ (loss) for the periods indicated: Three Months Ended March 31, (In thousands) 2021 2020 Unrealized gains on investments available-for-sale: Affected line item in the Statements of Income: Investment securities gains $ 58 $ 169 Income before taxes 58 169 Tax expense (15) (42) Net income $ 43 $ 127 Amortization of defined benefit pension plan items: Affected line item in the Statements of Income: Recognized actuarial loss (1) $ (227) $ (219) Loss before taxes (227) (219) Tax benefit 63 55 Net loss $ (164) $ (164) (1) This amount is included in the computation of net periodic benefit cost. See Note 11 for additional information on the pension plan.

LEASES

LEASES	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Leases	LEASES The Company leases real estate properties for its network of bank branches, financial centers and corporate offices. All of the Company’s leases are currently classified as operating. Most lease agreements include one or more options to renew, with renewal terms that can extend the original lease term from one The following table provides information regarding the Company's leases as of the dates indicated: Three Months Ended March 31, 2021 2020 Components of lease expense: Operating lease cost (resulting from lease payments) $ 3,151 $ 2,730 Supplemental cash flow information related to leases: Operating cash flows from operating leases $ 3,280 $ 2,082 ROU assets obtained in the exchange for lease liabilities due to: New leases $ 803 $ — Acquisitions $ — $ 311 March 31, 2021 December 31, 2020 Supplemental balance sheet information related to leases: Operating lease ROU assets $ 64,455 $ 65,215 Operating lease liabilities $ 74,219 $ 74,982 Other information related to leases: Weighted average remaining lease term of operating leases 9.4 years 9.5 years Weighted average discount rate of operating leases 2.97% 3.04% At March 31, 2021, the maturities of the Company’s operating lease liabilities were as follows: (In thousands) Amount Maturity: Remaining 2021 $ 9,346 2022 11,068 2023 11,054 2024 9,251 2025 7,537 Thereafter 38,522 Total undiscounted lease payments 86,778 Less: Present value discount (12,559) Lease liability $ 74,219 The Company recognized lease liabilities of $1.9 million and ROU assets of $1.6 million for two operating leases that have not yet commenced operations at March 31, 2021. One lease is expected to commence operations during the second quarter of 2021 and one is expected to commence operations during the fourth quarter of 2021. The associated ROU assets include approximately $0.2 million of tenant allowances for improvements to the spaces. The Company does not have any lease arrangements with any of its related parties as of March 31, 2021.

DERIVATIVES

DERIVATIVES	3 Months Ended
	Mar. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVES	DERIVATIVESThe Company has entered into interest rate swaps (“swaps”) to facilitate customer transactions and meet their financing needs. These swaps qualify as derivatives, but are not designated as hedging instruments. Interest rate swap contracts involve the risk of dealing with counterparties and their ability to meet contractual terms. When the fair value of a derivative instrument contract is positive, this generally indicates that the counterparty or customer owes the Company and results in credit risk to the Company. When the fair value of a derivative instrument contract is negative, the Company owes the customer or counterparty and, therefore, has no credit risk. The notional value of the swaps outstanding was $374.7 million as of March 31, 2021 compared to $320.5 million as of December 31, 2020. The fair values of swap positions net to zero to minimize the potential impact on the Company’s Condensed Consolidated Financial Statements. Fair values of the swaps are carried as both gross assets and gross liabilities in other assets and other liabilities, respectively, in the Condensed Consolidated Statements of Condition. The associated net gains and losses on the swaps are recorded in Other income in the Condensed Consolidated Statements of Income.

LITIGATION

LITIGATION	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
LITIGATION	LITIGATIONThe Company and its subsidiaries are subject in the ordinary course of business to various pending or threatened legal proceedings in which claims for monetary damages are asserted. After consultation with legal counsel, management does not anticipate that the ultimate liability, if any, arising out of these legal matters will have a material adverse effect on the Company's financial condition, operating results or liquidity.

FAIR VALUE

FAIR VALUE	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
FAIR VALUE	FAIR VALUE GAAP provides entities the option to measure eligible financial assets, financial liabilities and commitments at fair value (i.e. the fair value option), on an instrument-by-instrument basis, that are otherwise not permitted to be accounted for at fair value under other accounting standards. The election to use the fair value option is available when an entity first recognizes a financial asset or financial liability or upon entering into a commitment. Subsequent changes in fair value must be recorded in earnings. The Company applies the fair value option on residential mortgage loans held for sale. The fair value option on residential mortgage loans held for sale allows the recognition of gains on the sale of mortgage loans to more accurately reflect the timing and economics of the transaction. The standard for fair value measurement establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below. Basis of Fair Value Measurement: Level 1- Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2- Quoted prices in markets that are not active, or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability; Level 3- Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e. supported by little or no market activity). A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Changes to interest rates may result in changes in the cash flows due to prepayments or extinguishments. Accordingly, changes to interest rates could result in higher or lower measurements of the fair values. Assets and Liabilities Residential mortgage loans held for sale Residential mortgage loans held for sale are valued based on quotations from the secondary market for similar instruments and are classified as Level 2 in the fair value hierarchy. Investments available-for-sale U.S. treasuries and government agencies securities and mortgage-backed and asset-backed securities Valuations are based on active market data and use of evaluated broker pricing models that vary based by asset class and includes available trade, bid, and other market information. Generally, the methodology includes broker quotes, proprietary models, descriptive terms, and databases coupled with extensive quality control programs. Quality control evaluation processes use available market, credit and deal level information to support the evaluation of the security. Additionally, proprietary models and pricing systems, mathematical tools, actual transacted prices, integration of market developments and experienced evaluators are used to determine the value of a security based on a hierarchy of market information regarding a security or securities with similar characteristics. The Company does not adjust the quoted price for such securities. Such instruments are classified within Level 2 in the fair value hierarchy. State and municipal securities The Company primarily uses prices obtained from third-party pricing services to determine the fair value of securities. The Company independently evaluates and corroborates the fair value received from pricing services through various methods and techniques, including references to dealer or other market quotes, by reviewing valuations of comparable instruments, and by comparing the prices realized on the sale of similar securities. Such securities are classified within Level 2 in the fair value hierarchy. Corporate debt The fair value of corporate debt is determined by utilizing a discounted cash flow valuation technique employed by a third-party valuation specialist. The third-party specialist uses assumptions related to yield, prepayment speed, conditional default rates and loss severity based on certain factors such as, credit worthiness of the counterparty, prevailing market rates, and analysis of similar securities. The Company evaluates the fair values provided by the third-party specialist for reasonableness and classifies them as level 3 in the fair value hierarchy. Interest rate swap agreements Interest rate swap agreements are measured by alternative pricing sources using a discounted cash flow method that incorporates current market interest rates. Based on the complex nature of interest rate swap agreements, the markets these instruments trade in are not as efficient and are less liquid than that of the more mature Level 1 markets. These characteristics classify interest rate swap agreements as Level 2 in the fair value hierarchy. Assets Measured at Fair Value on a Recurring Basis The following tables set forth the Company’s financial assets and liabilities at the dates indicated that were accounted for or disclosed at fair value. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement: March 31, 2021 Quoted Prices in Significant Other Significant (In thousands) (Level 1) (Level 2) (Level 3) Total Assets: Residential mortgage loans held for sale (1) $ — $ 84,930 $ — $ 84,930 Investments available-for-sale: U.S. treasuries and government agencies — 48,086 — 48,086 State and municipal — 366,032 — 366,032 Mortgage-backed and asset-backed — 1,006,179 — 1,006,179 Corporate debt — — 7,583 7,583 Total investments available-for-sale — 1,420,297 7,583 1,427,880 Interest rate swap agreements — 6,402 — 6,402 Total assets $ — $ 1,511,629 $ 7,583 $ 1,519,212 Liabilities: Interest rate swap agreements $ — $ (6,402) $ — $ (6,402) Total liabilities $ — $ (6,402) $ — $ (6,402) (1) The outstanding principal balance for residential loans held for sale as of March 31, 2021 was $83.3 million. December 31, 2020 Quoted Prices in Significant Other Significant (In thousands) (Level 1) (Level 2) (Level 3) Total Assets: Residential mortgage loans held for sale (1) $ — $ 78,294 $ — $ 78,294 Investments available-for-sale: U.S. treasuries and government agencies — 43,297 — 43,297 State and municipal — 390,367 — 390,367 Mortgage-backed and asset-backed — 904,432 — 904,432 Corporate debt — — 9,925 9,925 Total investments available-for-sale — 1,338,096 9,925 1,348,021 Interest rate swap agreements — 9,183 — 9,183 Total assets $ — $ 1,425,573 $ 9,925 $ 1,435,498 Liabilities: Interest rate swap agreements $ — $ (9,183) $ — $ (9,183) Total liabilities $ — $ (9,183) $ — $ (9,183) (1) The outstanding principal balance for residential loans held for sale as of December 31, 2020 was $75.5 million. The following table provides a change in the fair value of assets measured in the Condensed Consolidated Statements of Condition at fair value with significant unobservable inputs (Level 3) on a recurring basis for the period indicated: Significant (In thousands) (Level 3) Investments available-for-sale: Balance at January 1, 2021 $ 9,925 Additions of Level 3 assets — Sales of Level 3 assets (2,102) Total unrealized loss included in other comprehensive income/ (loss) (240) Balance at March 31, 2021 $ 7,583 Assets Measured at Fair Value on a Nonrecurring Basis The following tables set forth the Company’s financial assets subject to fair value adjustments on a nonrecurring basis at the date indicated that are valued at the lower of cost or market. Assets are classified in their entirety based on the lowest level of input that is significant to the fair value measurement: March 31, 2021 (In thousands) Quoted Prices in Significant Significant Total Total Losses Loans (1) $ — $ — $ 5,513 $ 5,513 $ (5,780) Other real estate owned — — 1,354 1,354 (387) Total $ — $ — $ 6,867 $ 6,867 $ (6,167) (1) Amounts represent the fair value of collateral for collateral dependent non-accrual loans allocated to the allowance for credit losses. Fair values are determined using actual market prices (Level 2), independent third party valuations and borrower records, discounted as appropriate (Level 3). December 31, 2020 (In thousands) Quoted Prices in Significant Significant Total Total Losses Loans (1) $ — $ — $ 13,901 $ 13,901 $ (11,326) Other real estate owned — — 1,455 1,455 (286) Total $ — $ — $ 15,356 $ 15,356 $ (11,612) (1) Amounts represent the fair value of collateral for collateral dependent non-accrual loans allocated to the allowance for credit losses. Fair values are determined using actual market prices (Level 2), independent third party valuations and borrower records, discounted as appropriate (Level 3). At March 31, 2021, loans totaling $82.0 million were written down to fair value of $68.9 million as a result of individual credit loss allowances of $13.1 million associated with the collateral dependent loans. Loans totaling $97.7 million were written down to fair value of $86.3 million at December 31, 2020 as a result of individual credit loss allowances of $11.4 million associated with the collateral dependent loans. Fair value of the collateral dependent loans is measured based on the loan’s observable market price or the fair value of the collateral (less estimated selling costs). Collateral may be real estate and/or business assets such as equipment, inventory and/or accounts receivable. The value of business equipment, inventory and accounts receivable collateral is based on net book value on the business’ financial statements and, if necessary, discounted based on management’s review and analysis. Appraised and reported values may be discounted based on management’s historical experience, changes in market conditions from the time of valuation, and/or management’s expertise and knowledge of the client and client’s business. Collateral dependent loans are reviewed and evaluated on at least a quarterly basis for additional individual reserve and adjusted accordingly, based on the factors identified above. OREO is adjusted to fair value upon acquisition of the real estate collateral. Subsequently, OREO is carried at the lower of carrying value or fair value. The estimated fair value for OREO included in Level 3 is determined by independent market based appraisals and other available market information, less costs to sell, that may be reduced further based on market expectations or an executed sales agreement. If the fair value of the collateral deteriorates subsequent to initial recognition, the Company records the OREO as a nonrecurring Level 3 adjustment. Valuation techniques are consistent with those techniques applied in prior periods. Fair Value of Financial Instruments The Company discloses fair value information, based on the exit price notion, of financial instruments that are not measured at fair value in the financial statements. Fair value is the amount at which a financial instrument could be exchanged in a current transaction between willing parties, other than in a forced sale or liquidation, and is best evidenced by a quoted market price, if one exists. Quoted market prices, where available, are shown as estimates of fair market values. Because no quoted market prices are available for a significant portion of the Company's financial instruments, the fair value of such instruments has been derived based on the amount and timing of future cash flows and estimated discount rates based on observable inputs (“Level 2”) or unobservable inputs (“Level 3”). Present value techniques used in estimating the fair value of many of the Company's financial instruments are significantly affected by the assumptions used. In that regard, the derived fair value estimates cannot be substantiated by comparison to independent markets and, in many cases, could not be realized in immediate cash settlement of the instrument. Additionally, the accompanying estimates of fair values are only representative of the fair values of the individual financial assets and liabilities, and should not be considered an indication of the fair value of the Company. Management utilizes internal models used in asset liability management to determine the fair values disclosed below. The carrying amounts and fair values of the Company’s financial instruments at the dates indicated are presented in the following tables: Fair Value Measurements March 31, 2021 Quoted Prices in Significant Other Significant (In thousands) Carrying Estimated Financial assets: Cash and cash equivalents $ 228,621 $ 228,621 $ 228,621 $ — $ — Residential mortgage loans held for sale 84,930 84,930 — 84,930 — Investments available-for-sale 1,427,880 1,427,880 — 1,420,297 7,583 Equity securities 44,847 44,847 44,847 — — Loans, net of allowance 10,316,505 10,339,985 — — 10,339,985 Interest rate swap agreements 6,402 6,402 — 6,402 — Accrued interest receivable 44,559 44,559 44,559 — — Bank owned life insurance 127,567 127,567 — 127,567 — Financial liabilities: Time deposits $ 1,675,166 $ 1,687,100 $ — $ 1,687,100 $ — Other deposits 9,002,586 9,002,586 9,002,586 — — Securities sold under retail repurchase agreements and federal funds purchased 189,318 189,318 — 189,318 — Advances from FHLB 100,000 100,327 — 100,327 — Subordinated debt 227,044 217,942 — — 217,942 Interest rate swap agreements 6,402 6,402 — 6,402 — Accrued interest payable 4,019 4,019 4,019 — — Fair Value Measurements December 31, 2020 Quoted Prices in Significant Other Significant (In thousands) Carrying Estimated Financial assets: Cash and cash equivalents $ 297,003 $ 297,003 $ 297,003 $ — $ — Residential mortgage loans held for sale 78,294 78,294 — 78,294 — Investments available-for-sale 1,348,021 1,348,021 — 1,338,096 9,925 Equity securities 65,760 65,760 65,760 — — Loans, net of allowance 10,235,142 10,336,355 — — 10,336,355 Interest rate swap agreements 9,183 9,183 — 9,183 — Accrued interest receivable 46,431 46,431 46,431 — — Bank owned life insurance 126,887 126,887 — 126,887 — Financial liabilities: Time deposits $ 1,657,662 $ 1,674,112 $ — $ 1,674,112 $ — Other deposits 8,375,407 8,375,407 8,375,407 — — Securities sold under retail repurchase agreements and federal funds purchased 543,157 543,157 — 543,157 — Advances from FHLB 379,075 390,593 — 390,593 — Subordinated debt 227,088 227,512 — — 227,512 Interest rate swap agreements 9,183 9,183 — 9,183 — Accrued interest payable 3,254 3,254 3,254 — —

SEGMENT REPORTING

SEGMENT REPORTING	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
SEGMENT REPORTING	SEGMENT REPORTING Currently, the Company conducts business in three operating segments - Community Banking, Insurance, and Investment Management. Each of the operating segments is a strategic business unit that offers different products and services. The Insurance and Investment Management segments were businesses that were acquired in separate transactions where management of the acquired business was retained. The accounting policies of the segments are the same as those of the Company. However, the segment data reflects inter-segment transactions and balances. The Community Banking segment is conducted through Sandy Spring Bank and involves delivering a broad range of financial products and services, including various loan and deposit products, to both individuals and businesses. Parent company income and assets are included in the Community Banking segment, as the majority of parent company functions are related to this segment. Major revenue sources include net interest income, gains on sales of mortgage loans, trust income fees, and service charges on deposit accounts. Expenses include personnel, occupancy, marketing, equipment, and other expenses. Non-cash charges associated with amortization of intangibles were $1.2 million and $0.4 million for the three months ended March 31, 2021 and 2020, respectively. The Insurance segment is conducted through Sandy Spring Insurance, a subsidiary of the Bank. Sandy Spring Insurance operates Sandy Spring Insurance, a general insurance agency located in Annapolis, Maryland, and Neff and Associates, located in Ocean City, Maryland. Major sources of revenue are insurance commissions from commercial lines, personal lines, and medical liability lines. Expenses include personnel, occupancy, support charges, and other expenses. Non-cash charges associated with amortization of intangibles were immaterial for the three months ended March 31, 2021 and 2020. The Investment Management segment is conducted through West Financial and RPJ, subsidiaries of the Bank. These asset management and financial planning firms, located in McLean, Virginia and Falls Church, Virginia, respectively, provide comprehensive investment management and financial planning to individuals, families, small businesses and associations, including cash flow analysis, investment review, tax planning, retirement planning, insurance analysis and estate planning. West Financial and RPJ had approximately $3.6 billion in combined assets under management as of March 31, 2021. Major revenue sources include non-interest income earned on the above services. Expenses include personnel, occupancy, support charges, and other expenses. Non-cash charges associated with amortization of intangibles for the three months ended March 31, 2021 and 2020 were $0.5 million and $0.2 million, respectively. Information for the operating segments and reconciliation of the information to the Condensed Consolidated Financial Statements for the periods indicated are presented in the following tables: Three Months Ended March 31, 2021 (In thousands) Community Insurance Investment Inter-Segment Total Interest income $ 114,261 $ 1 $ 2 $ (3) $ 114,261 Interest expense 9,664 — — (3) 9,661 Provision for credit losses (34,708) — — — (34,708) Non-interest income 21,725 2,151 5,207 (217) 28,866 Non-interest expense 63,695 1,487 3,208 (217) 68,173 Income before income taxes 97,335 665 2,001 — 100,001 Income tax expense 23,838 183 516 — 24,537 Net income $ 73,497 $ 482 $ 1,485 $ — $ 75,464 Assets $ 12,878,311 $ 11,504 $ 56,688 $ (73,137) $ 12,873,366 Three Months Ended March 31, 2020 (In thousands) Community Insurance Investment Inter-Segment Total Interest income $ 83,857 $ 3 $ 2 $ (4) $ 83,858 Interest expense 19,528 — — (4) 19,524 Provision for credit losses 24,469 — — — 24,469 Non-interest income 13,977 2,129 2,266 (204) 18,168 Non-interest expense 44,655 1,464 1,831 (204) 47,746 Income before income taxes 9,182 668 437 — 10,287 Income tax expense 1 185 114 — 300 Net income $ 9,181 $ 483 $ 323 $ — $ 9,987 Assets $ 8,917,849 $ 10,887 $ 55,657 $ (54,791) $ 8,929,602

SIGNIFICANT ACCOUNTING POLICI_2

SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations Sandy Spring Bancorp, Inc. ("Sandy Spring" or, together with its subsidiaries, the "Company"), a Maryland corporation, is the bank holding company for Sandy Spring Bank (the “Bank”). Independent and community-oriented, Sandy Spring Bank offers a broad range of commercial banking, retail banking, mortgage services and trust services throughout central Maryland, Northern Virginia, and the greater Washington, D.C. market. Sandy Spring Bank also offers a comprehensive menu of insurance and wealth management services through its subsidiaries, Sandy Spring Insurance Corporation (“Sandy Spring Insurance”), West Financial Services, Inc. (“West Financial”) and Rembert Pendleton Jackson (“RPJ”).
Basis of Presentation	Basis of Presentation The accounting and reporting policies of the Company conform to accounting principles generally accepted in the United States of America (“GAAP”), prevailing practices within the financial services industry for interim financial information and Rule 10-01 of Regulation S-X. Accordingly, the interim financial statements do not include all of the information and notes required for complete financial statements. The following summary of significant accounting policies of the Company is presented to assist the reader in understanding the financial and other data presented in this report. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for any future periods or for the year ending December 31, 2021. In the opinion of management, all adjustments necessary for a fair presentation of the results of the interim periods have been included. Certain reclassifications have been made to prior period amounts, as necessary, to conform to the current period presentation. The Company has evaluated subsequent events through the date of the issuance of its financial statements. These statements should be read in conjunction with the financial statements and accompanying notes included in the Company’s 2020 Annual Report on Form 10-K as filed with the Securities and Exchange Commission (“SEC”) on February 19, 2021. There have been no significant changes to any of the Company’s accounting policies as disclosed in the 2020 Annual Report on Form 10-K.
Principles of Consolidation	Principles of Consolidation The unaudited Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiary, Sandy Spring Bank, and its subsidiaries, Sandy Spring Insurance, West Financial and RPJ. Consolidation has resulted in the elimination of all intercompany accounts and transactions. See Note 18 for more information on the Company’s segments and consolidation.
Use of Estimates	Use of Estimates The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements, in addition to affecting the reported amounts of revenues earned and expenses incurred during the reporting period. Actual results could differ from those estimates. Estimates that could change significantly relate to the provision for credit losses and the related allowance, potential impairment of goodwill or other intangible assets, valuation of investment securities and the determination of whether available-for-sale debt securities with fair values less than amortized costs are impaired and require an allowance for credit losses, valuation of other real estate owned, valuation of share based compensation, the assessment that a liability should be recognized with respect to any matters under litigation, the calculation of current and deferred income taxes, and the actuarial projections related to pension expense and the related liability.
Cash Flows	Cash Flows For purposes of reporting cash flows, cash and cash equivalents include cash and due from banks, federal funds sold and interest-bearing deposits with banks (items with stated original maturity of three months or less).
Revenue from Contracts with Customers	Revenue from Contracts with Customers The Company’s revenue includes net interest income on financial instruments and non-interest income. Specific categories of revenue are presented in the Condensed Consolidated Statements of Income. Most of the Company’s revenue is not within the scope of Accounting Standard Codification (“ASC”) 606 – Revenue from Contracts with Customers. For revenue within the scope of ASC 606, the Company provides services to customers and has related performance obligations. The revenue from such services is recognized upon satisfaction of all contractual performance obligations. The following discusses key revenue streams within the scope of revenue recognition guidance. Wealth Management Income West Financial and RPJ provide comprehensive investment management and financial planning services. Wealth management income is comprised of income for providing trust, estate and investment management services. Trust services include acting as a trustee for corporate or personal trusts. Investment management services include investment management, record-keeping and reporting of security portfolios. Fees for these services are recognized based on a contractually-agreed fixed percentage applied to net assets under management at the end of each reporting period. The Company does not charge/recognize any performance-based fees. Insurance Agency Commissions Sandy Spring Insurance, a subsidiary of the Bank, performs the function of an insurance intermediary by introducing the policyholder and insurer and is compensated by a commission fee for placement of an insurance policy. Sandy Spring Insurance does not provide any captive management services or any claim handling services. Commission fees are set as a percentage of the premium for the insurance policy for which Sandy Spring Insurance is a producer. Sandy Spring Insurance recognizes revenue when the insurance policy has been contractually agreed to by the insurer and policyholder (at transaction date). Service Charges on Deposit Accounts Service charges on deposit accounts are earned on depository accounts for consumer and commercial account holders and include fees for account and overdraft services. Account services include fees for event-driven services and periodic account maintenance activities. An obligation for event-driven services is satisfied at the time of the event when service is delivered and revenue recognized as earned. Obligation for maintenance activities is satisfied over the course of each month and revenue is recognized at month end. The overdraft services obligation is satisfied at the time of the overdraft and revenue is recognized as earned.
Loan Financing Receivables	Loan Financing Receivables The Company’s financing receivables consist primarily of loans that are stated at their principal balance outstanding, net of any unearned income, acquisition fair value marks and deferred loan origination fees and costs. Interest income on loans is accrued at the contractual rate based on the principal balance outstanding. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the related loan yield using the interest method. Loans are considered past due or delinquent when the principal or interest due in accordance with the contractual terms of the loan agreement or any portion thereof remains unpaid after the due date of the scheduled payment. Immaterial shortfalls in payment amounts do not necessarily result in a loan being considered delinquent or past due. If any payments are past due and subsequent payments are resumed without payment of the delinquent amount, the loan shall continue to be considered past due. Whenever any loan is reported delinquent on a principal or interest payment or portion thereof, the amount reported as delinquent is the outstanding principal balance of the loan. Loans, except for consumer installment loans, are placed into non-accrual status when any portion of the loan principal or interest becomes 90 days past due. Management may determine that certain circumstances warrant earlier discontinuance of interest accruals on specific loans if an evaluation of other relevant factors (such as bankruptcy, interruption of cash flows, etc.) indicates collection of amounts contractually due is unlikely. These loans are considered, collectively, to be non-performing loans. Consumer installment loans that are not secured by real estate are not placed on non-accrual, but are charged down to their net realizable value when they are four months past due. Loans designated as non-accrual have all previously accrued but unpaid interest reversed. Interest income is not recognized on non-accrual loans. All payments received on non-accrual loans are applied using a cost-recovery method to reduce the outstanding principal balance until the loan returns to accrual status. Loans may be returned to accrual status when all principal and interest amounts contractually due are brought current and future payments are reasonably assured. Loans considered to be TDRs are loans that have their terms restructured (e.g., interest rates, loan maturity date, payment and amortization period, etc.) in circumstances that provide payment relief to a borrower experiencing financial difficulty. All restructured collateral-dependent loans are individually assessed for allowance for credit losses and may either be in accruing or non-accruing status. Non-accruing restructured loans may return to accruing status provided doubt has been removed concerning the collectability of principal and interest as evidenced by a sufficient period of payment performance in accordance with the restructured terms. Loans may be removed from the restructured category if the borrower is no longer experiencing financial difficulty, a re-underwriting event took place, and the revised loan terms of the subsequent restructuring agreement are considered to be consistent with terms that can be obtained in the market for loans with comparable credit risk.
Allowance for Credit Losses	Allowance for Credit Losses The allowance for credit losses (“allowance” or “ACL”) represents an amount which, in management's judgment, is adequate to absorb the lifetime expected losses that may be sustained on outstanding loans at the balance sheet date based on the evaluation of the size and current risk characteristics of the loan portfolio, past events, current conditions, reasonable and supportable forecasts of future economic conditions and prepayment experience. The allowance is measured and recorded upon the initial recognition of a financial asset. The allowance is reduced by charge-offs, net of recoveries of previous losses, and is increased or decreased by a provision or credit for credit losses, which is recorded as a current period expense. Determination of the adequacy of the allowance is inherently complex and requires the use of significant and highly subjective estimates. The reasonableness of the allowance is reviewed periodically by the Risk Committee of the Board of Directors and formally approved quarterly by that same committee of the Board. The Company’s methodology for estimating the allowance includes: (1) a collective quantified reserve that reflects the Company’s historical default and loss experience adjusted for expected economic conditions throughout a reasonable and supportable period and the Company’s prepayment and curtailment rates; (2) collective qualitative factors that consider concentrations of the loan portfolio, expected changes to the economic forecasts, large relationships, early delinquencies, and factors related to credit administration, including, among others, loan-to-value ratios, borrowers’ risk rating and credit score migrations; and (3) individual allowances on collateral-dependent loans where borrowers are experiencing financial difficulty or when the Company determines that the foreclosure is probable. The Company excludes accrued interest from the measurement of the allowance as the Company has a non-accrual policy to reverse any accrued, uncollected interest income as loans are moved to non-accrual status. Loans are pooled into segments based on the similar risk characteristics of the underlying borrowers, in addition to consideration of collateral type, industry and business purpose of the loans. Portfolio segments used to estimate the allowance are the same as portfolio segments used for general credit risk management purposes. Refer to Note 4 for more details on the Company’s portfolio segments. The Company applies two calculation methodologies to estimate the collective quantified component of the allowance: discounted cash flows method and weighted average remaining life method. Allowance estimates on commercial acquisition, development and construction (“AD&C”) and residential construction segments are based on the weighted average remaining life method. Allowance estimates on all other portfolio segments are based on the discounted cash flows method. Segments utilizing the discounted cash flows method are further sub-segmented into risk level pools, determined either by risk rating for commercial loans or Beacon Scores ranges for residential and consumer loans. To better manage risk and reasonably determine the sufficiency of reserves, this segregation allows the Company to monitor the allowance component applicable to higher risk loans separate from the remainder of the portfolio. Collective calculation methodologies utilize the Company’s historical default and loss experience adjusted for future economic forecasts. The reasonable and supportable forecast period represents a two-year economic outlook for the applicable economic variables. Following the end of the reasonable and supportable forecast period expected losses revert back to the historical mean over the next two years on a straight-line basis. Economic variables that have the most significant impact on the allowance include: unemployment rate, house price index and number of business bankruptcies. Contractual loan level cash flows within the discounted cash flows methodology are adjusted for the Company’s historical prepayment and curtailment rate experience. The individual reserve assessment is applied to collateral dependent loans where borrowers are experiencing financial difficulty or when the Company determines that a foreclosure is probable. The determination of the fair value of the collateral depends on whether a repayment of the loan is expected to be from the sale or the operation of the collateral. When a repayment is expected from the operation of the collateral, the Company uses the present value of expected cash flows from the operation of the collateral as the fair value. When the repayment of the loan is expected from the sale of the collateral the fair value of the collateral is based on an observable market price or the collateral’s appraised value, less estimated costs to sell. Third party appraisals used in the individual reserve assessment are conducted at least annually with underlying assumptions that are reviewed by management. Third party appraisals may be obtained on a more frequent basis if deemed necessary. Internal evaluations of collateral value are conducted quarterly to ensure any further deterioration of the collateral value is recognized on a timely basis. During the individual reserve assessment, management also considers the potential future changes in the value of the collateral over the remainder of the loan’s remaining life. The Company may receive updated appraisals which contradict the preliminary determination of fair value used to establish an individual allowance on a loan. In these instances the individual allowance is adjusted to reflect the Company’s evaluation of the updated appraised fair value. In the event a loss was previously confirmed and the loan was charged down to the estimated fair value based on a previous appraisal, the balance of partially charged-off loans are not subsequently increased, but could be further decreased depending on the direction of the change in fair value. Payments on fully or partially charged-off loans are accounted for under the cost-recovery method. Under this method, all payments received are applied on a cash basis to reduce the entire outstanding principal balance, then to recognize a recovery of all previously charged-off amounts before any interest income may be recognized. Based on the individual reserve assessment, if the Company determines that the fair value of the collateral is less than the amortized cost basis of the loan, an individual allowance will be established measured as the difference between the fair value of the collateral (less costs to sell) and the amortized cost basis of the loan. Once a loss has been confirmed, the loan is charged-down to its estimated fair value. Large groups of smaller non-accrual homogeneous loans are not individually evaluated for allowance and include residential permanent and construction mortgages and consumer installment loans. These portfolios are reserved for on a collective basis using historical loss rates of similar loans over the weighted average life of each pool. The Company reviews its unfunded commitments to determine if they are unconditionally cancellable by the Company. If the unfunded commitment is determined to not be unconditionally cancellable by the Company, a reserve for unfunded commitments is established. The reserve for unfunded commitments considers both the likelihood that the funding will occur and an estimate of expected credit losses over the life of the commitment. Management believes it uses relevant information available to make determinations about the allowance and that it has established the existing allowance in accordance with GAAP. However, the determination of the allowance requires significant judgment, and estimates of expected lifetime losses in the loan portfolio can vary significantly from the amounts actually observed. While management uses available information to recognize expected losses, future additions to the allowance may be necessary based on changes in the loans comprising the portfolio, changes in the current and forecasted economic conditions, changes to the interest rate environment which may directly impact prepayment and curtailment rate assumptions, and changes in the financial condition of borrowers.
Acquired Loans	Acquired Loans Loans acquired in connection with acquisitions are recorded at their acquisition-date fair value. The allowance for credit losses related to the acquired loan portfolio is not carried over. Acquired loans are classified into two categories based on the credit risk characteristics of the underlying borrowers as either purchased credit deteriorated (“PCD”) loans, or loans with no evidence of credit deterioration (“non-PCD”). PCD loans are defined as a loan or pool of loans that have experienced more-than-insignificant credit deterioration since the origination date. The Company uses a combination of individual and pooled review approaches to determine if acquired loans are PCD. At acquisition, the Company considers a number of factors to determine if an acquired loan or pool of loans has experienced more-than-insignificant credit deterioration. These factors include: • loans classified as non-accrual, • loans with risk rating of special mention or worse (using the Company's risk rating scale), • loans with multiple risk rating downgrades since origination, • loans with evidence of being 60 days or more past due, • loans previously modified in a troubled debt restructuring, • loans that received an interest only or payment deferral modification, and • loans in industries that show evidence of additional risk due to economic conditions. The initial allowance related to PCD loans that share similar risk characteristics is established using a pooled approach. The Company uses either a discounted cash flow or weighted average remaining life method to determine the required level of the allowance. PCD loans that were classified as non-accrual as of the acquisition date and are collateral dependent are assessed for allowance on an individual basis. For PCD loans, an initial allowance is established on the acquisition date and added to the fair value of the loan to arrive at acquisition date amortized cost. Accordingly, no provision for credit losses is recognized on PCD loans at the acquisition date. Subsequent to the acquisition date, the initial allowance on PCD loans will increase or decrease based on future evaluations, with changes recognized in the provision for credit losses. Non-PCD loans are pooled into segments together with originated loans that share similar risk characteristics and have an allowance established on the acquisition date, which is recognized in the current period provision for credit losses. Determining the fair value of the acquired loans involves estimating the principal and interest payment cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. Management considers a number of factors in evaluating the acquisition-date fair value including the remaining life, interest rate profile, market interest rate environment, payment schedules, risk ratings, probability of default and loss given default, and estimated prepayment rates. For PCD loans, the non-credit discount or premium is allocated to individual loans as determined by the difference between the loan’s unpaid principal balance and amortized cost basis. The non-credit premium or discount is recognized into interest income on a level yield basis over the remaining expected life of the loan. For non-PCD loans, the fair value discount or premium is
Leases	Leases The Company determines if an arrangement is a lease at inception. All of the Company’s leases are currently classified as operating leases and are included in other assets and other liabilities on the Company’s Condensed Consolidated Statements of Condition. Right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term, and lease liabilities represent the Company’s obligation to make lease payments arising from the lease arrangements. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of the expected future lease payments over the remaining lease term. In determining the present value of future lease payments, the Company uses its incremental borrowing rate based on the information available at the lease commencement date. The operating ROU assets are adjusted for any lease payments made at or before the lease commencement date, initial direct costs, any lease incentives received and, for acquired leases, any favorable or unfavorable fair value adjustments. The present value of the lease liability may include the impact of options to extend or terminate the lease when it is reasonably certain that the Company will exercise such options provided in the lease terms. Lease expense is recognized on a straight-line basis over the expected lease term. Lease agreements that include lease and non-lease components, such as common area maintenance charges, are accounted for separately.
Pending Accounting Pronouncements	Pending Accounting Pronouncements In March 2020, FASB released Accounting Standards Update (“ASU”) 2020-04 - Reference Rate Reform (Topic 848) , which provides optional guidance to ease the accounting burden in accounting for, or recognizing the effects from, reference rate reform on financial reporting. The new standard is a result of LIBOR likely being discontinued as an available benchmark rate. The standard is elective and provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, or other transactions that reference LIBOR, or another reference rate expected to be discontinued. The amendments in the update are effective for all entities between March 12, 2020 and December 31, 2022. The Company has established a cross-functional working group to guide the Company’s transition from LIBOR and has begun efforts to transition to alternative rates consistent with industry timelines. The Company has identified its products that utilize LIBOR and has implemented enhanced fallback language to facilitate the transition to alternative reference rates. The Company is evaluating existing platforms and systems and preparing to offer new rates.

ACQUISITION OF REVERE BANK (Tab

ACQUISITION OF REVERE BANK (Tables)	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
Provisional fair values of acquired identifiable assets and liabilities assumed	The consideration paid for Revere’s common equity and outstanding stock options and the provisional fair values of acquired identifiable assets and assumed identifiable liabilities as of March 31, 2021 were as follows: (Dollars in thousands, except per share data) March 31, 2021 Purchase price: Fair value of common shares issued (12,768,949 shares) based on Sandy Spring's share price of $22.64 $ 289,089 Fair value of Revere stock options converted to Sandy Spring stock options 3,611 Cash paid for cashed-out Revere stock options 291 Cash for fractional shares 11 Total purchase price $ 293,002 Identifiable assets: Cash and cash equivalents $ 80,744 Investments available-for-sale 180,752 Loans 2,502,244 Premises and equipment 3,443 Accrued interest receivable 7,651 Core deposit intangible asset 18,360 Other assets 53,162 Total identifiable assets $ 2,846,356 Identifiable liabilities: Deposits $ 2,322,422 Borrowings 205,514 Other liabilities 25,933 Total identifiable liabilities $ 2,553,869 Fair value of net assets acquired including identifiable intangible assets 292,487 Goodwill $ 515

INVESTMENTS (Tables)

INVESTMENTS (Tables)	3 Months Ended
	Mar. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Unrealized Gain (Loss) on Investments	The amortized cost and estimated fair values of investments available-for-sale at the dates indicated are presented in the following table: March 31, 2021 December 31, 2020 (In thousands) Amortized Gross Gross Estimated Amortized Gross Gross Estimated U.S. treasuries and government agencies $ 47,641 $ 447 $ (2) $ 48,086 $ 42,750 $ 549 $ (2) $ 43,297 State and municipal 362,815 7,926 (4,709) 366,032 377,108 13,470 (211) 390,367 Mortgage-backed and asset-backed 1,001,475 15,222 (10,518) 1,006,179 881,201 24,078 (847) 904,432 Corporate debt 7,000 583 — 7,583 9,100 825 — 9,925 Total investments available-for-sale $ 1,418,931 $ 24,178 $ (15,229) $ 1,427,880 $ 1,310,159 $ 38,922 $ (1,060) $ 1,348,021
Schedule of Unrealized Loss on Investments	Gross unrealized losses and fair value by length of time that the individual available-for-sale securities have been in an unrealized loss position at the dates indicated are presented in the following tables: March 31, 2021 Number Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. treasuries and government agencies 1 $ 4,972 $ 2 $ — $ — $ 4,972 $ 2 State and municipal 43 115,530 4,709 — — 115,530 4,709 Mortgage-backed and asset-backed 46 373,235 10,509 4,968 9 378,203 10,518 Total 90 $ 493,737 $ 15,220 $ 4,968 $ 9 $ 498,705 $ 15,229 December 31, 2020 Number Less Than 12 Months 12 Months or More Total (Dollars in thousands) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses U.S. treasuries and government agencies 2 $ 25,369 $ 2 $ — $ — $ 25,369 $ 2 State and municipal 8 22,753 211 — — 22,753 211 Mortgage-backed and asset-backed 24 44,746 154 76,879 693 121,625 847 Total 34 $ 92,868 $ 367 $ 76,879 $ 693 $ 169,747 $ 1,060
Estimated fair values of debt securities available-for-sale by contractual maturity	March 31, 2021 December 31, 2020 (In thousands) Fair Value Amortized Cost Fair Value Amortized Cost U.S. treasuries and government agencies: One year or less $ 36,904 $ 36,744 $ 33,963 $ 33,833 One to five years 11,182 10,897 9,334 8,917 Five to ten years — — — — After ten years — — — — State and municipal: One year or less 13,175 13,098 16,581 16,458 One to five years 38,077 36,965 44,910 43,857 Five to ten years 49,417 47,569 59,059 56,130 After ten years 265,363 265,183 269,817 260,663 Mortgage-backed and asset-backed: One year or less 1,923 1,905 1 1 One to five years 20,180 19,822 21,637 21,229 Five to ten years 67,401 66,718 74,142 72,481 After ten years 916,675 913,030 808,652 787,490 Corporate debt: One year or less — — — — One to five years — — 2,318 2,100 Five to ten years 7,583 7,000 7,607 7,000 After ten years — — — — Total available-for-sale debt securities $ 1,427,880 $ 1,418,931 $ 1,348,021 $ 1,310,159
Other Equity Securities	Other equity securities at the dates indicated are presented in the following table: (In thousands) March 31, 2021 December 31, 2020 Federal Reserve Bank stock $ 34,028 $ 38,650 Federal Home Loan Bank of Atlanta stock 10,142 26,433 Marketable equity securities 677 677 Total equity securities $ 44,847 $ 65,760

LOANS (Tables)

LOANS (Tables)	3 Months Ended
	Mar. 31, 2021
Receivables [Abstract]
Loan Portfolio Segment Balances	The loan portfolio segment balances at the dates indicated are presented in the following table: (In thousands) March 31, 2021 December 31, 2020 Commercial real estate: Commercial investor real estate $ 3,652,418 $ 3,634,720 Commercial owner-occupied real estate 1,644,848 1,642,216 Commercial AD&C 1,051,013 1,050,973 Commercial business 2,411,109 2,267,548 Total commercial loans 8,759,388 8,595,457 Residential real estate: Residential mortgage 1,022,546 1,105,179 Residential construction 171,028 182,619 Consumer 493,904 517,254 Total residential and consumer loans 1,687,478 1,805,052 Total loans $ 10,446,866 $ 10,400,509

CREDIT QUALITY ASSESSMENT (Tabl

CREDIT QUALITY ASSESSMENT (Tables)	3 Months Ended
	Mar. 31, 2021
Credit Loss [Abstract]
Summary Information On The Allowance For Credit Loss Activity	Summary information on the allowance for credit loss activity for the period indicated is provided in the following table: Three Months Ended March 31, (In thousands) 2021 2020 Balance at beginning of period $ 165,367 $ 56,132 Initial allowance on PCD loans at adoption of ASC 326 — 2,762 Transition impact of adopting ASC 326 — 2,983 Provision for credit losses (34,708) 24,469 Loan charge-offs (743) (654) Loan recoveries 445 108 Net charge-offs (298) (546) Balance at period end $ 130,361 $ 85,800
Activity in Allowance for Credit Losses or Loan and Lease Losses by Respective Loan Portfolio Segment	The following table provides summary information regarding collateral dependent loans individually evaluated for credit loss at the dates indicated: (In thousands) March 31, 2021 December 31, 2020 Collateral dependent loans individually evaluated for credit loss with an allowance $ 32,241 $ 20,717 Collateral dependent loans individually evaluated for credit loss without an allowance 49,757 77,001 Total individually evaluated collateral dependent loans $ 81,998 $ 97,718 Allowance for credit losses related to loans evaluated individually $ 13,101 $ 11,405 Allowance for credit losses related to loans evaluated collectively 117,260 153,962 Total allowance for credit losses $ 130,361 $ 165,367 The following tables provide information on the activity in the allowance for credit losses by the respective loan portfolio segment for the period indicated: For the Three Months Ended March 31, 2021 Commercial Real Estate Residential Real Estate (Dollars in thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Balance at beginning of period $ 57,404 $ 20,061 $ 22,157 $ 46,806 $ 11,295 $ 1,502 $ 6,142 $ 165,367 Provision for credit losses (8,981) (5,594) 760 (14,343) (4,018) (849) (1,683) (34,708) Charge-offs — — — (650) — — (93) (743) Recoveries 27 — — 16 270 — 132 445 Net recoveries (charge-offs) 27 — — (634) 270 — 39 (298) Balance at end of period $ 48,450 $ 14,467 $ 22,917 $ 31,829 $ 7,547 $ 653 $ 4,498 $ 130,361 Total loans $ 3,652,418 $ 1,644,848 $ 1,051,013 $ 2,411,109 $ 1,022,546 $ 171,028 $ 493,904 $ 10,446,866 Allowance for credit losses to total loans ratio 1.33 % 0.88 % 2.18 % 1.32 % 0.74 % 0.38 % 0.91 % 1.25 % Balance of loans individually evaluated for credit loss $ 42,776 $ 8,316 $ 14,975 $ 13,831 $ 1,737 $ — $ 363 $ 81,998 Allowance related to loans evaluated individually $ 2,988 $ — $ 603 $ 9,510 $ — $ — $ — $ 13,101 Individual allowance to loans evaluated individually ratio 6.99 % — % 4.03 % 68.76 % — % — % — % 15.98 % Balance of loans collectively evaluated for credit loss $ 3,609,642 $ 1,636,532 $ 1,036,038 $ 2,397,278 $ 1,020,809 $ 171,028 $ 493,541 $ 10,364,868 Allowance related to loans evaluated collectively $ 45,462 $ 14,467 $ 22,314 $ 22,319 $ 7,547 $ 653 $ 4,498 $ 117,260 Collective allowance to loans evaluated collectively ratio 1.26 % 0.88 % 2.15 % 0.93 % 0.74 % 0.38 % 0.91 % 1.13 % For the Year Ended December 31, 2020 Commercial Real Estate Residential Real Estate (Dollars in thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Balance at beginning of period $ 18,407 $ 6,884 $ 7,590 $ 11,395 $ 8,803 $ 967 $ 2,086 $ 56,132 Initial allowance on PCD loans at adoption of ASC 326 1,114 — — 1,549 — — 99 2,762 Transition impact of adopting ASC 326 (3,125) 387 2,576 2,988 (388) (275) 820 2,983 Initial allowance on acquired Revere PCD loans 7,973 2,782 1,248 6,289 243 6 87 18,628 Provision for credit losses 33,431 10,008 10,743 24,374 3,016 798 3,299 85,669 Charge-offs (411) — — (491) (484) — (433) (1,819) Recoveries 15 — — 702 105 6 184 1,012 Net recoveries (charge-offs) (396) — — 211 (379) 6 (249) (807) Balance at end of period $ 57,404 $ 20,061 $ 22,157 $ 46,806 $ 11,295 $ 1,502 $ 6,142 $ 165,367 Total loans $ 3,634,720 $ 1,642,216 $ 1,050,973 $ 2,267,548 $ 1,105,179 $ 182,619 $ 517,254 $ 10,400,509 Allowance for credit losses to total loans ratio 1.58 % 1.22 % 2.11 % 2.06 % 1.02 % 0.82 % 1.19 % 1.59 % Balance of loans individually evaluated for credit loss $ 45,227 $ 11,561 $ 15,044 $ 23,648 $ 1,874 $ — $ 364 $ 97,718 Allowance related to loans evaluated individually $ 1,273 $ — $ 603 $ 9,529 $ — $ — $ — $ 11,405 Individual allowance to loans evaluated individually ratio 2.81 % — % 4.01 % 40.30 % — % — % — % 11.67 % Balance of loans collectively evaluated for credit loss $ 3,589,493 $ 1,630,655 $ 1,035,929 $ 2,243,900 $ 1,103,305 $ 182,619 $ 516,890 $ 10,302,791 Allowance related to loans evaluated collectively $ 56,131 $ 20,061 $ 21,554 $ 37,277 $ 11,295 $ 1,502 $ 6,142 $ 153,962 Collective allowance to loans evaluated collectively ratio 1.56 % 1.23 % 2.08 % 1.66 % 1.02 % 0.82 % 1.19 % 1.49 %
Schedule Of Collateral Dependent Loans Individually Evaluated For Credit Loss With The Associated Allowances	The following tables present collateral dependent loans individually evaluated for credit loss with the associated allowances for credit losses by the applicable portfolio segment and for the periods indicated: March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Loans individually evaluated for credit loss with an allowance: Non-accruing $ 17,686 $ — $ 1,446 $ 9,730 $ — $ — $ — $ 28,862 Restructured accruing — — — 573 — — — 573 Restructured non-accruing 336 — — 2,470 — — — 2,806 Balance $ 18,022 $ — $ 1,446 $ 12,773 $ — $ — $ — $ 32,241 Allowance $ 2,988 $ — $ 603 $ 9,510 $ — $ — $ — $ 13,101 Loans individually evaluated for credit loss without an allowance: Non-accruing $ 24,754 $ 6,125 $ 13,529 $ 318 $ — $ — $ — $ 44,726 Restructured accruing — — — 111 1,587 — — 1,698 Restructured non-accruing — 2,191 — 629 150 — 363 3,333 Balance $ 24,754 $ 8,316 $ 13,529 $ 1,058 $ 1,737 $ — $ 363 $ 49,757 Total individually evaluated loans: Non-accruing $ 42,440 $ 6,125 $ 14,975 $ 10,048 $ — $ — $ — $ 73,588 Restructured accruing — — — 684 1,587 — — 2,271 Restructured non-accruing 336 2,191 — 3,099 150 — 363 6,139 Balance $ 42,776 $ 8,316 $ 14,975 $ 13,831 $ 1,737 $ — $ 363 $ 81,998 Total unpaid contractual principal balance $ 47,547 $ 10,306 $ 16,157 $ 16,088 $ 2,814 $ — $ 364 $ 93,276 December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Loans individually evaluated for credit loss with an allowance: Non-accruing $ 4,913 $ — $ 1,328 $ 11,178 $ — $ — $ — $ 17,419 Restructured accruing — — — 589 — — — 589 Restructured non-accruing 699 — — 2,010 — — — 2,709 Balance $ 5,612 $ — $ 1,328 $ 13,777 $ — $ — $ — $ 20,717 Allowance $ 1,273 $ — $ 603 $ 9,529 $ — $ — $ — $ 11,405 Loans individually evaluated for credit loss without an allowance: Non-accruing $ 39,615 $ 9,315 $ 13,716 $ 9,118 $ — $ — $ — $ 71,764 Restructured accruing — — — 126 1,602 — — 1,728 Restructured non-accruing — 2,246 — 627 272 — 364 3,509 Balance $ 39,615 $ 11,561 $ 13,716 $ 9,871 $ 1,874 $ — $ 364 $ 77,001 Total individually evaluated loans: Non-accruing $ 44,528 $ 9,315 $ 15,044 $ 20,296 $ — $ — $ — $ 89,183 Restructured accruing — — — 715 1,602 — — 2,317 Restructured non-accruing 699 2,246 — 2,637 272 — 364 6,218 Balance $ 45,227 $ 11,561 $ 15,044 $ 23,648 $ 1,874 $ — $ 364 $ 97,718 Total unpaid contractual principal balance $ 49,920 $ 15,309 $ 16,040 $ 30,958 $ 3,225 $ — $ 364 $ 115,816
Table Of Average Principal Balance Of The Total Non-Accrual Loans, Contractual Interest Due And Interest Income	The following tables present average principal balance of total non-accrual loans and contractual interest due on non-accrual loans for the periods indicated below: For the Three Months Ended March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Average non-accrual loans for the period $ 44,002 $ 9,939 $ 15,010 $ 18,040 $ 9,903 $ — $ 7,289 $ 104,183 Contractual interest income due on non- accrual loans during the period $ 649 $ 185 $ 256 $ 428 $ 110 $ — $ 104 $ 1,732 For the Year Ended December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Average non-accrual loans for the period $ 26,849 $ 6,605 $ 4,267 $ 16,532 $ 11,634 $ — $ 6,675 $ 72,562 Contractual interest income due on non- accrual loans during the period $ 6,547 $ 2,741 $ 4,505 $ 2,858 $ 918 $ — $ 732 $ 18,301
Schedule Of Information On The Credit Quality Of Loan Portfolio Under The New CECL	The following section provides information on the credit quality of the loan portfolio for the periods indicated below: For the Three Months Ended March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Analysis of non-accrual loan activity: Balance at beginning of period $ 45,227 $ 11,561 $ 15,044 $ 22,933 $ 10,212 $ — $ 7,384 $ 112,361 Loans placed on non-accrual — — — 84 140 — 197 421 Non-accrual balances transferred to OREO — — — — — — — — Non-accrual balances charged-off — — — (650) — — (49) (699) Net payments or draws (2,451) (3,245) (69) (9,220) (759) — (284) (16,028) Non-accrual loans brought current — — — — — — (55) (55) Balance at end of period $ 42,776 $ 8,316 $ 14,975 $ 13,147 $ 9,593 $ — $ 7,193 $ 96,000 For the Year Ended December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Analysis of non-accrual loan activity: Balance at beginning of period $ 8,437 $ 4,148 $ 829 $ 8,450 $ 12,661 $ — $ 4,107 $ 38,632 PCD loans designated as non-accrual (1) 9,544 — — 2,539 8 — 993 13,084 Loans placed on non-accrual 37,882 8,572 15,844 17,442 1,485 — 4,061 85,286 Non-accrual balances transferred to OREO — — — — (70) — — (70) Non-accrual balances charged-off (411) — — (446) (416) — (121) (1,394) Net payments or draws (10,225) (1,059) (1,629) (4,169) (2,598) — (1,521) (21,201) Non-accrual loans brought current — (100) — (883) (858) — (135) (1,976) Balance at end of period $ 45,227 $ 11,561 $ 15,044 $ 22,933 $ 10,212 $ — $ 7,384 $ 112,361 (1) Upon the adoption of the CECL standard, the Company transitioned from closed pool level accounting for PCI loans during the first quarter of 2020. Non-accrual loans are determined based on the individual loan level and aggregated for reporting.
Credit Quality of Loan Portfolio by Segment	March 31, 2021 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Performing loans: Current $ 3,587,859 $ 1,633,446 $ 1,031,055 $ 2,392,818 $ 997,837 $ 170,365 $ 483,280 $ 10,296,660 30-59 days 17,870 3,086 4,983 3,983 9,593 601 1,809 41,925 60-89 days 3,913 — — 446 3,538 62 1,622 9,581 Total performing loans 3,609,642 1,636,532 1,036,038 2,397,247 1,010,968 171,028 486,711 10,348,166 Non-performing loans: Non-accrual loans 42,776 8,316 14,975 13,147 9,593 — 7,193 96,000 Loans greater than 90 days past due — — — 31 398 — — 429 Restructured loans — — — 684 1,587 — — 2,271 Total non-performing loans 42,776 8,316 14,975 13,862 11,578 — 7,193 98,700 Total loans $ 3,652,418 $ 1,644,848 $ 1,051,013 $ 2,411,109 $ 1,022,546 $ 171,028 $ 493,904 $ 10,446,866 December 31, 2020 Commercial Real Estate Residential Real Estate (In thousands) Commercial Commercial Commercial Commercial Residential Residential Consumer Total Performing loans: Current $ 3,571,184 $ 1,624,265 $ 1,033,057 $ 2,238,617 $ 1,073,963 $ 182,557 $ 502,548 $ 10,226,191 30-59 days 14,046 6,390 29 4,859 16,213 — 5,275 46,812 60-89 days 4,130 — 2,843 263 2,709 62 2,047 12,054 Total performing loans 3,589,360 1,630,655 1,035,929 2,243,739 1,092,885 182,619 509,870 10,285,057 Non-performing loans: Non-accrual loans 45,227 11,561 15,044 22,933 10,212 — 7,384 112,361 Loans greater than 90 days past due 133 — — 161 480 — — 774 Restructured loans — — — 715 1,602 — — 2,317 Total non-performing loans 45,360 11,561 15,044 23,809 12,294 — 7,384 115,452 Total loans $ 3,634,720 $ 1,642,216 $ 1,050,973 $ 2,267,548 $ 1,105,179 $ 182,619 $ 517,254 $ 10,400,509
Information About Credit Quality Indicator By The Year Of Origination	The following table provides information about credit quality indicators by the year of origination as of March 31, 2021: March 31, 2021 Term Loans by Origination Year Revolving (In thousands) 2021 2020 2019 2018 2017 Prior Loans Total Commercial Investor R/E: Pass $ 194,465 $ 881,973 $ 707,450 $ 452,909 $ 429,839 $ 876,375 $ 28,844 $ 3,571,855 Special Mention 10,000 527 1,993 2,640 701 2,646 — 18,507 Substandard 279 437 6,175 13,555 28,149 13,461 — 62,056 Doubtful — — — — — — — — Total $ 204,744 $ 882,937 $ 715,618 $ 469,104 $ 458,689 $ 892,482 $ 28,844 $ 3,652,418 Commercial Owner-Occupied R/E: Pass $ 47,661 $ 287,070 $ 375,951 $ 222,539 $ 188,795 $ 485,151 $ 4,793 $ 1,611,960 Special Mention — 1,871 4,327 3,586 4,698 5,279 — 19,761 Substandard — 1,269 4,316 2,031 447 5,064 — 13,127 Doubtful — — — — — — — — Total $ 47,661 $ 290,210 $ 384,594 $ 228,156 $ 193,940 $ 495,494 $ 4,793 $ 1,644,848 Commercial AD&C: Pass $ 174,120 $ 373,158 $ 244,751 $ 110,557 $ 47,150 $ — $ 80,645 $ 1,030,381 Special Mention 639 1,073 — — — — — 1,712 Substandard 1,102 455 891 — 13,629 2,843 — 18,920 Doubtful — — — — — — — — Total $ 175,861 $ 374,686 $ 245,642 $ 110,557 $ 60,779 $ 2,843 $ 80,645 $ 1,051,013 Commercial Business: Pass $ 459,815 $ 1,059,494 $ 179,214 $ 129,096 $ 77,302 $ 71,681 $ 396,258 $ 2,372,860 Special Mention — 2,043 8,793 1,063 1,214 845 3,792 17,750 Substandard 225 4,785 3,494 3,338 857 6,019 1,781 20,499 Doubtful — — — — — — — — Total $ 460,040 $ 1,066,322 $ 191,501 $ 133,497 $ 79,373 $ 78,545 $ 401,831 $ 2,411,109 Residential Mortgage: Beacon score: 660-850 $ 43,362 $ 209,544 $ 66,700 $ 113,850 $ 153,972 $ 336,256 $ — $ 923,684 600-659 745 4,962 9,539 8,498 8,044 25,851 — 57,639 540-599 — 1,445 1,181 5,063 1,930 14,187 — 23,806 less than 540 497 2,318 1,545 3,182 1,118 8,757 — 17,417 Total $ 44,604 $ 218,269 $ 78,965 $ 130,593 $ 165,064 $ 385,051 $ — $ 1,022,546 Residential Construction: Beacon score: 660-850 $ 27,097 $ 101,290 $ 21,059 $ 14,166 $ 1,248 $ 1,738 $ 364 $ 166,962 600-659 — — 2,743 — — 369 — 3,112 540-599 — — — — — — — — less than 540 — 954 — — — — — 954 Total $ 27,097 $ 102,244 $ 23,802 $ 14,166 $ 1,248 $ 2,107 $ 364 $ 171,028 Consumer: Beacon score: 660-850 $ 1,054 $ 2,200 $ 4,263 $ 4,213 $ 1,567 $ 27,406 $ 400,050 $ 440,753 600-659 247 265 1,138 484 259 6,092 17,590 26,075 540-599 — 105 564 272 270 3,425 6,938 11,574 less than 540 103 729 151 569 765 3,277 9,908 15,502 Total $ 1,404 $ 3,299 $ 6,116 $ 5,538 $ 2,861 $ 40,200 $ 434,486 $ 493,904 Total loans $ 961,411 $ 2,937,967 $ 1,646,238 $ 1,091,611 $ 961,954 $ 1,896,722 $ 950,963 $ 10,446,866 The following table provides information about credit quality indicators by the year of origination as of December 31, 2020: December 31, 2020 Term Loans by Origination Year Revolving (In thousands) 2020 2019 2018 2017 2016 Prior Loans Total Commercial Investor R/E: Pass $ 910,426 $ 763,214 $ 448,406 $ 448,698 $ 469,077 $ 498,384 $ 33,531 $ 3,571,736 Special Mention 11,044 — 4,879 833 269 27 — 17,052 Substandard 589 4,245 13,649 20,619 673 6,157 — 45,932 Doubtful — — — — — — — — Total $ 922,059 $ 767,459 $ 466,934 $ 470,150 $ 470,019 $ 504,568 $ 33,531 $ 3,634,720 Commercial Owner-Occupied R/E: Pass $ 285,310 $ 385,058 $ 234,578 $ 192,634 $ 204,925 $ 306,840 $ 1,664 $ 1,611,009 Special Mention 2,290 — 3,027 4,742 134 4,079 — 14,272 Substandard 1,610 4,335 2,065 465 219 8,009 — 16,703 Doubtful — — — — — 232 — 232 Total $ 289,210 $ 389,393 $ 239,670 $ 197,841 $ 205,278 $ 319,160 $ 1,664 $ 1,642,216 Commercial AD&C: Pass $ 485,631 $ 261,537 $ 149,703 $ 50,192 $ 89 $ 2,357 $ 80,764 $ 1,030,273 Special Mention 1,711 — — — — — — 1,711 Substandard 1,439 891 — 13,816 2,843 — — 18,989 Doubtful — — — — — — — — Total $ 488,781 $ 262,428 $ 149,703 $ 64,008 $ 2,932 $ 2,357 $ 80,764 $ 1,050,973 Commercial Business: Pass $ 1,244,822 $ 208,682 $ 138,861 $ 86,830 $ 34,498 $ 81,760 $ 433,016 $ 2,228,469 Special Mention 1,929 1,382 1,119 708 309 621 4,319 10,387 Substandard 2,914 4,564 3,519 1,631 2,745 3,456 1,829 20,658 Doubtful 106 995 849 36 1,284 1,852 2,912 8,034 Total $ 1,249,771 $ 215,623 $ 144,348 $ 89,205 $ 38,836 $ 87,689 $ 442,076 $ 2,267,548 Residential Mortgage: Beacon score: 660-850 $ 229,033 $ 74,054 $ 138,824 $ 172,493 $ 129,701 $ 251,065 $ — $ 995,170 600-659 4,824 7,706 10,763 11,719 8,173 21,424 — 64,609 540-599 350 1,238 5,219 2,608 4,791 10,167 — 24,373 less than 540 2,702 2,108 3,576 2,150 892 9,599 — 21,027 Total $ 236,909 $ 85,106 $ 158,382 $ 188,970 $ 143,557 $ 292,255 $ — $ 1,105,179 Residential Construction: Beacon score: 660-850 $ 112,604 $ 44,647 $ 14,543 $ 2,805 $ 1,693 $ — $ 172 $ 176,464 600-659 1,743 3,189 — — — — — 4,932 540-599 — — — — 369 — — 369 less than 540 854 — — — — — — 854 Total $ 115,201 $ 47,836 $ 14,543 $ 2,805 $ 2,062 $ — $ 172 $ 182,619 Consumer: Beacon score: 660-850 $ 2,575 $ 4,609 $ 5,112 $ 2,110 $ 2,614 $ 24,444 $ 417,737 $ 459,201 600-659 374 445 334 428 467 5,401 21,052 28,501 540-599 89 1,216 294 339 601 3,926 6,153 12,618 less than 540 751 160 525 785 532 2,826 11,355 16,934 Total $ 3,789 $ 6,430 $ 6,265 $ 3,662 $ 4,214 $ 36,597 $ 456,297 $ 517,254 Total loans $ 3,305,720 $ 1,774,275 $ 1,179,845 $ 1,016,641 $ 866,898 $ 1,242,626 $ 1,014,504 $ 10,400,509
Restructured Loans for Specific Segments of Loan Portfolio	The following table provides the amounts of the restructured loans at the date of restructuring for specific segments of the loan portfolio during the period indicated: For the Three Months Ended March 31, 2021 Commercial Real Estate (In thousands) Commercial Commercial Commercial Commercial All Total Troubled debt restructurings: Restructured accruing $ — $ — $ — $ — $ — $ — Restructured non-accruing — — — 512 — 512 Balance $ — $ — $ — $ 512 $ — $ 512 Individual allowance $ — $ — $ — $ 332 $ — $ 332 Restructured and subsequently defaulted $ — $ — $ — $ — $ — $ — For the Year Ended December 31, 2020 Commercial Real Estate (In thousands) Commercial Commercial Commercial Commercial All Total Troubled debt restructurings: Restructured accruing $ — $ — $ — $ 380 $ 549 $ 929 Restructured non-accruing 723 930 — 1,951 — 3,604 Balance $ 723 $ 930 $ — $ 2,331 $ 549 $ 4,533 Individual allowance $ 65 $ — $ — $ 955 $ — $ 1,020 Restructured and subsequently defaulted $ — $ — $ — $ — $ — $ —

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Gross Carrying Amounts and Accumulated Amortization of Intangible Assets and Goodwill	The gross carrying amounts and accumulated amortization of intangible assets and goodwill are presented at the dates indicated in the following table: March 31, 2021 Weighted December 31, 2020 Weighted (Dollars in thousands) Gross Accumulated Net Gross Accumulated Net Amortizing intangible assets: Core deposit intangibles $ 29,038 $ (9,169) $ 19,869 8.2 years $ 29,038 $ (7,969) $ 21,069 8.4 years Other identifiable intangibles 13,906 (2,951) 10,955 10.5 years 13,906 (2,454) 11,452 10.7 years Total amortizing intangible assets $ 42,944 $ (12,120) $ 30,824 $ 42,944 $ (10,423) $ 32,521 Goodwill $ 370,223 $ 370,223 $ 370,223 $ 370,223
Net carrying amount of goodwill by segment	The amount of goodwill by reportable segment is presented in the following table: (In thousands) Community Insurance Investment Total Balances at December 31, 2020 $ 331,688 $ 6,788 $ 31,747 $ 370,223 No Activity — — — — Balances at March 31, 2021 $ 331,688 $ 6,788 $ 31,747 $ 370,223
Estimated Future Amortization Expense for Amortizing Intangibles	The following table presents the estimated future amortization expense for amortizing intangible assets within the years ending December 31: (In thousands) Amount Remaining 2021 $ 4,903 2022 5,844 2023 5,089 2024 4,333 2025 3,567 Thereafter 7,088 Total amortizing intangible assets $ 30,824

DEPOSITS (Tables)

DEPOSITS (Tables)	3 Months Ended
	Mar. 31, 2021
Deposits [Abstract]
Composition of Deposits	(In thousands) March 31, 2021 December 31, 2020 Noninterest-bearing deposits $ 3,770,852 $ 3,325,547 Interest-bearing deposits: Demand 1,395,209 1,292,164 Money market savings 3,371,400 3,339,645 Regular savings 465,125 418,051 Time deposits of less than $100,000 474,684 509,919 Time deposits greater than $100,000 and less than $250,000 774,668 670,717 Time deposits of $250,000 or more 425,814 477,026 Total interest-bearing deposits 6,906,900 6,707,522 Total deposits $ 10,677,752 $ 10,033,069

BORROWINGS (Tables)

BORROWINGS (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Subordinated Borrowing	The following table provides information on subordinated debt as of the date indicated: (In thousands) March 31, 2021 December 31, 2020 Fixed to floating rate sub debt, 4.25% $ 175,000 $ 175,000 WashingtonFirst sub debt, 4.81% 25,000 25,000 Revere fixed to floating rate sub debt, 5.625% 31,000 31,000 Total Sub debt 231,000 231,000 Less: Debt held as investments by Sandy Spring (3,000) (3,000) Add: Purchase accounting premium 1,552 1,669 Less: Debt issuance costs (2,508) (2,581) Long-term borrowings $ 227,044 $ 227,088

SHARE BASED COMPENSATION (Table

SHARE BASED COMPENSATION (Tables)	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Summary of Share Option Activity	A summary of share option activity for the period indicated is reflected in the following table: Number Weighted Weighted Aggregate Balance at January 1, 2021 430,038 $ 14.97 3.0 years $ 6,828 Granted — $ — Exercised (102,365) $ 14.96 $ 2,381 Forfeited — $ — Expired — $ — Balance at March 31, 2021 327,673 $ 14.98 2.6 years $ 9,045 Exercisable at March 31, 2021 322,908 $ 14.63 2.6 years $ 9,017
Summary of Activity for Company's Restricted Stock	A summary of the activity for the Company’s restricted stock, restricted stock units and performance share units for the period indicated is presented in the following table: Number Weighted Non-vested at January 1, 2021 391,683 $ 29.50 Granted 119,329 $ 40.70 Vested (13,669) $ 37.64 Forfeited/ cancelled (3,988) $ 34.86 Non-vested at March 31, 2021 493,355 $ 31.94

PENSION PLAN (Tables)

PENSION PLAN (Tables)	3 Months Ended
	Mar. 31, 2021
Retirement Benefits [Abstract]
Net Periodic Benefit Cost	The components of net periodic benefit cost for the periods indicated are presented in the following table: Three Months Ended March 31, (In thousands) 2021 2020 Interest cost on projected benefit obligation $ 318 $ 359 Expected return on plan assets (312) (456) Recognized net actuarial loss 227 219 Net periodic benefit cost $ 233 $ 122

NET INCOME_ (LOSS) PER COMMON S

NET INCOME/ (LOSS) PER COMMON SHARE (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Calculation of Net Income Per Common Share	The calculation of net income per common share for the periods indicated is presented in the following table: Three Months Ended March 31, (Dollars and amounts in thousands, except per share data) 2021 2020 Net income $ 75,464 $ 9,987 Distributed and undistributed earnings allocated to (640) (68) Net income attributable to common shareholders $ 74,824 $ 9,919 Total weighted average outstanding shares 47,530 34,979 Less: Weighted average participating securities (411) (314) Basic weighted average common shares 47,119 34,665 Dilutive weighted average common stock equivalents 296 78 Diluted weighted average common shares 47,415 34,743 Basic net income per common share $ 1.59 $ 0.29 Diluted net income per common share $ 1.58 $ 0.28 Anti-dilutive shares 3 9

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Activity in net accumulated other comprehensive income (loss) and the components of the activity	The following table presents the activity in net accumulated other comprehensive income/ (loss) and the components of the activity for the periods indicated: (In thousands) Unrealized Gains Defined Benefit Total Balance at January 1, 2021 $ 28,175 $ (9,470) $ 18,705 Other comprehensive loss before reclassification, net of tax (21,478) — (21,478) Reclassifications from accumulated other comprehensive income, net of tax (43) 164 121 Current period change in other comprehensive income, net of tax (21,521) 164 (21,357) Balance at March 31, 2021 $ 6,654 $ (9,306) $ (2,652) (In thousands) Unrealized Gains/ Defined Benefit Total Balance at January 1, 2020 $ 4,000 $ (8,332) $ (4,332) Other comprehensive income before reclassification, net of tax 10,639 — 10,639 Reclassifications from accumulated other comprehensive income, net of tax (127) 164 37 Current period change in other comprehensive income, net of tax 10,512 164 10,676 Balance at March 31, 2020 $ 14,512 $ (8,168) $ 6,344
Schedule of reclassification adjustments out of accumulated other comprehensive income (loss)	The following table provides the information on the reclassification adjustments out of accumulated other comprehensive income/ (loss) for the periods indicated: Three Months Ended March 31, (In thousands) 2021 2020 Unrealized gains on investments available-for-sale: Affected line item in the Statements of Income: Investment securities gains $ 58 $ 169 Income before taxes 58 169 Tax expense (15) (42) Net income $ 43 $ 127 Amortization of defined benefit pension plan items: Affected line item in the Statements of Income: Recognized actuarial loss (1) $ (227) $ (219) Loss before taxes (227) (219) Tax benefit 63 55 Net loss $ (164) $ (164) (1) This amount is included in the computation of net periodic benefit cost. See Note 11 for additional information on the pension plan.

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Lease, Cost	The following table provides information regarding the Company's leases as of the dates indicated: Three Months Ended March 31, 2021 2020 Components of lease expense: Operating lease cost (resulting from lease payments) $ 3,151 $ 2,730 Supplemental cash flow information related to leases: Operating cash flows from operating leases $ 3,280 $ 2,082 ROU assets obtained in the exchange for lease liabilities due to: New leases $ 803 $ — Acquisitions $ — $ 311 March 31, 2021 December 31, 2020 Supplemental balance sheet information related to leases: Operating lease ROU assets $ 64,455 $ 65,215 Operating lease liabilities $ 74,219 $ 74,982 Other information related to leases: Weighted average remaining lease term of operating leases 9.4 years 9.5 years Weighted average discount rate of operating leases 2.97% 3.04%
Maturities of operating lease liabilities	At March 31, 2021, the maturities of the Company’s operating lease liabilities were as follows: (In thousands) Amount Maturity: Remaining 2021 $ 9,346 2022 11,068 2023 11,054 2024 9,251 2025 7,537 Thereafter 38,522 Total undiscounted lease payments 86,778 Less: Present value discount (12,559) Lease liability $ 74,219

FAIR VALUE (Tables)

FAIR VALUE (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Financial assets and Liabilities at Dates Indicated that were Accounted for at Fair Value	The following tables set forth the Company’s financial assets and liabilities at the dates indicated that were accounted for or disclosed at fair value. Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement: March 31, 2021 Quoted Prices in Significant Other Significant (In thousands) (Level 1) (Level 2) (Level 3) Total Assets: Residential mortgage loans held for sale (1) $ — $ 84,930 $ — $ 84,930 Investments available-for-sale: U.S. treasuries and government agencies — 48,086 — 48,086 State and municipal — 366,032 — 366,032 Mortgage-backed and asset-backed — 1,006,179 — 1,006,179 Corporate debt — — 7,583 7,583 Total investments available-for-sale — 1,420,297 7,583 1,427,880 Interest rate swap agreements — 6,402 — 6,402 Total assets $ — $ 1,511,629 $ 7,583 $ 1,519,212 Liabilities: Interest rate swap agreements $ — $ (6,402) $ — $ (6,402) Total liabilities $ — $ (6,402) $ — $ (6,402) (1) The outstanding principal balance for residential loans held for sale as of March 31, 2021 was $83.3 million. December 31, 2020 Quoted Prices in Significant Other Significant (In thousands) (Level 1) (Level 2) (Level 3) Total Assets: Residential mortgage loans held for sale (1) $ — $ 78,294 $ — $ 78,294 Investments available-for-sale: U.S. treasuries and government agencies — 43,297 — 43,297 State and municipal — 390,367 — 390,367 Mortgage-backed and asset-backed — 904,432 — 904,432 Corporate debt — — 9,925 9,925 Total investments available-for-sale — 1,338,096 9,925 1,348,021 Interest rate swap agreements — 9,183 — 9,183 Total assets $ — $ 1,425,573 $ 9,925 $ 1,435,498 Liabilities: Interest rate swap agreements $ — $ (9,183) $ — $ (9,183) Total liabilities $ — $ (9,183) $ — $ (9,183) (1) The outstanding principal balance for residential loans held for sale as of December 31, 2020 was $75.5 million.
Change in Fair Value of Assets Measured in Condensed Consolidated Statements of Condition at Fair Value on a Recurring Basis	The following table provides a change in the fair value of assets measured in the Condensed Consolidated Statements of Condition at fair value with significant unobservable inputs (Level 3) on a recurring basis for the period indicated: Significant (In thousands) (Level 3) Investments available-for-sale: Balance at January 1, 2021 $ 9,925 Additions of Level 3 assets — Sales of Level 3 assets (2,102) Total unrealized loss included in other comprehensive income/ (loss) (240) Balance at March 31, 2021 $ 7,583
Assets Measured at Fair Value on Nonrecurring Basis	The following tables set forth the Company’s financial assets subject to fair value adjustments on a nonrecurring basis at the date indicated that are valued at the lower of cost or market. Assets are classified in their entirety based on the lowest level of input that is significant to the fair value measurement: March 31, 2021 (In thousands) Quoted Prices in Significant Significant Total Total Losses Loans (1) $ — $ — $ 5,513 $ 5,513 $ (5,780) Other real estate owned — — 1,354 1,354 (387) Total $ — $ — $ 6,867 $ 6,867 $ (6,167) (1) Amounts represent the fair value of collateral for collateral dependent non-accrual loans allocated to the allowance for credit losses. Fair values are determined using actual market prices (Level 2), independent third party valuations and borrower records, discounted as appropriate (Level 3). December 31, 2020 (In thousands) Quoted Prices in Significant Significant Total Total Losses Loans (1) $ — $ — $ 13,901 $ 13,901 $ (11,326) Other real estate owned — — 1,455 1,455 (286) Total $ — $ — $ 15,356 $ 15,356 $ (11,612) (1) Amounts represent the fair value of collateral for collateral dependent non-accrual loans allocated to the allowance for credit losses. Fair values are determined using actual market prices (Level 2), independent third party valuations and borrower records, discounted as appropriate (Level 3).
Carrying Amounts And Fair Values of Company's Financial Instruments	The carrying amounts and fair values of the Company’s financial instruments at the dates indicated are presented in the following tables: Fair Value Measurements March 31, 2021 Quoted Prices in Significant Other Significant (In thousands) Carrying Estimated Financial assets: Cash and cash equivalents $ 228,621 $ 228,621 $ 228,621 $ — $ — Residential mortgage loans held for sale 84,930 84,930 — 84,930 — Investments available-for-sale 1,427,880 1,427,880 — 1,420,297 7,583 Equity securities 44,847 44,847 44,847 — — Loans, net of allowance 10,316,505 10,339,985 — — 10,339,985 Interest rate swap agreements 6,402 6,402 — 6,402 — Accrued interest receivable 44,559 44,559 44,559 — — Bank owned life insurance 127,567 127,567 — 127,567 — Financial liabilities: Time deposits $ 1,675,166 $ 1,687,100 $ — $ 1,687,100 $ — Other deposits 9,002,586 9,002,586 9,002,586 — — Securities sold under retail repurchase agreements and federal funds purchased 189,318 189,318 — 189,318 — Advances from FHLB 100,000 100,327 — 100,327 — Subordinated debt 227,044 217,942 — — 217,942 Interest rate swap agreements 6,402 6,402 — 6,402 — Accrued interest payable 4,019 4,019 4,019 — — Fair Value Measurements December 31, 2020 Quoted Prices in Significant Other Significant (In thousands) Carrying Estimated Financial assets: Cash and cash equivalents $ 297,003 $ 297,003 $ 297,003 $ — $ — Residential mortgage loans held for sale 78,294 78,294 — 78,294 — Investments available-for-sale 1,348,021 1,348,021 — 1,338,096 9,925 Equity securities 65,760 65,760 65,760 — — Loans, net of allowance 10,235,142 10,336,355 — — 10,336,355 Interest rate swap agreements 9,183 9,183 — 9,183 — Accrued interest receivable 46,431 46,431 46,431 — — Bank owned life insurance 126,887 126,887 — 126,887 — Financial liabilities: Time deposits $ 1,657,662 $ 1,674,112 $ — $ 1,674,112 $ — Other deposits 8,375,407 8,375,407 8,375,407 — — Securities sold under retail repurchase agreements and federal funds purchased 543,157 543,157 — 543,157 — Advances from FHLB 379,075 390,593 — 390,593 — Subordinated debt 227,088 227,512 — — 227,512 Interest rate swap agreements 9,183 9,183 — 9,183 — Accrued interest payable 3,254 3,254 3,254 — —

SEGMENT REPORTING (Tables)

SEGMENT REPORTING (Tables)	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Operating Segments and Reconciliation of Information to Consolidated Financial Statements	Information for the operating segments and reconciliation of the information to the Condensed Consolidated Financial Statements for the periods indicated are presented in the following tables: Three Months Ended March 31, 2021 (In thousands) Community Insurance Investment Inter-Segment Total Interest income $ 114,261 $ 1 $ 2 $ (3) $ 114,261 Interest expense 9,664 — — (3) 9,661 Provision for credit losses (34,708) — — — (34,708) Non-interest income 21,725 2,151 5,207 (217) 28,866 Non-interest expense 63,695 1,487 3,208 (217) 68,173 Income before income taxes 97,335 665 2,001 — 100,001 Income tax expense 23,838 183 516 — 24,537 Net income $ 73,497 $ 482 $ 1,485 $ — $ 75,464 Assets $ 12,878,311 $ 11,504 $ 56,688 $ (73,137) $ 12,873,366 Three Months Ended March 31, 2020 (In thousands) Community Insurance Investment Inter-Segment Total Interest income $ 83,857 $ 3 $ 2 $ (4) $ 83,858 Interest expense 19,528 — — (4) 19,524 Provision for credit losses 24,469 — — — 24,469 Non-interest income 13,977 2,129 2,266 (204) 18,168 Non-interest expense 44,655 1,464 1,831 (204) 47,746 Income before income taxes 9,182 668 437 — 10,287 Income tax expense 1 185 114 — 300 Net income $ 9,181 $ 483 $ 323 $ — $ 9,987 Assets $ 8,917,849 $ 10,887 $ 55,657 $ (54,791) $ 8,929,602

ACQUISITION OF REVERE BANK - Na

ACQUISITION OF REVERE BANK - Narrative (Details) $ / shares in Units, $ in Thousands	Mar. 31, 2020USD ($)bank	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)	Apr. 01, 2020USD ($)$ / sharesshares
Business Acquisition [Line Items]
Total transaction value		$ 293,002
Assets		2,846,356
Provisional amount of goodwill recognized		$ 515		$ 800
Subsequent Event | Forecast
Business Acquisition [Line Items]
Provisional amount of goodwill recognized			$ 500
Sandy Spring Shareholders
Business Acquisition [Line Items]
Percentage of ownership in combined company				74.00%
Revere shareholders
Business Acquisition [Line Items]
Percentage of ownership in combined company				26.00%
Maryland-based Revere
Business Acquisition [Line Items]
Business acquisition rate of share exchange (in shares) | shares				1.05
Closing price (in dollars per share) | $ / shares				$ 22.64
Total transaction value	$ 293,000
Assets	$ 2,800,000
Number of banking offices | bank	11

ACQUISITION OF REVERE BANK - Pr

ACQUISITION OF REVERE BANK - Provisional fair values of acquired identifiable assets and liabilities assumed (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Apr. 01, 2020
Purchase price:
Fair value of common shares issued (12,768,949 shares) based on Sandy Spring's share price of $22.64	$ 289,089
Fair value of Revere stock options converted to Sandy Spring stock options	3,611
Cash paid for cashed-out Revere stock options	291
Cash for fractional shares	11
Total purchase price	293,002
Identifiable assets:
Cash and cash equivalents	80,744
Investments available-for-sale	180,752
Loans	2,502,244
Premises and equipment	3,443
Accrued interest receivable	7,651
Core deposit intangible asset	18,360
Other assets	53,162
Total identifiable assets	2,846,356
Identifiable liabilities:
Deposits	2,322,422
Borrowings	205,514
Other liabilities	25,933
Total identifiable liabilities	2,553,869
Fair value of net assets acquired including identifiable intangible assets	292,487
Goodwill	$ 515	$ 800
Stock issued during period (in shares)	12,768,949

INVESTMENTS - Amortized Cost an

INVESTMENTS - Amortized Cost and Estimated Fair Values of Investments Available-for-sale (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Total available-for-sale debt securities	$ 1,418,931	$ 1,310,159
Gross Unrealized Gains	24,178	38,922
Gross Unrealized Losses	15,229	1,060
Total available-for-sale debt securities	1,427,880	1,348,021
U.S. treasuries and government agencies
Debt Securities, Available-for-sale [Line Items]
Total available-for-sale debt securities	47,641	42,750
Gross Unrealized Gains	447	549
Gross Unrealized Losses	2	2
Total available-for-sale debt securities	48,086	43,297
State and municipal
Debt Securities, Available-for-sale [Line Items]
Total available-for-sale debt securities	362,815	377,108
Gross Unrealized Gains	7,926	13,470
Gross Unrealized Losses	4,709	211
Total available-for-sale debt securities	366,032	390,367
Mortgage-backed and asset-backed
Debt Securities, Available-for-sale [Line Items]
Total available-for-sale debt securities	1,001,475	881,201
Gross Unrealized Gains	15,222	24,078
Gross Unrealized Losses	10,518	847
Total available-for-sale debt securities	1,006,179	904,432
Corporate debt
Debt Securities, Available-for-sale [Line Items]
Total available-for-sale debt securities	7,000	9,100
Gross Unrealized Gains	583	825
Gross Unrealized Losses	0	0
Total available-for-sale debt securities	$ 7,583	$ 9,925

INVESTMENTS - Narrative (Detail

INVESTMENTS - Narrative (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Separate Account Investment [Line Items]
Investments available-for-sale book value	$ 454	$ 465.7
Government National Mortgage Association Certificates And Obligations Federal National Mortgage Association Certificates And Obligations And Federal Home Loan Mortgage Corporation Certificates And Obligations | Collateralized Mortgage Obligations
Fair Value, Separate Account Investment [Line Items]
Mortgage-backed securities	318.5
Government National Mortgage Association Certificates And Obligations Federal National Mortgage Association Certificates And Obligations And Federal Home Loan Mortgage Corporation Certificates And Obligations | Collateralized Mortgage Backed Securities
Fair Value, Separate Account Investment [Line Items]
Mortgage-backed securities	626
Government National Mortgage Association Certificates And Obligations Federal National Mortgage Association Certificates And Obligations And Federal Home Loan Mortgage Corporation Certificates And Obligations | SBA asset backed securities
Fair Value, Separate Account Investment [Line Items]
Mortgage-backed securities	$ 61.7

INVESTMENTS - Gross Unrealized

INVESTMENTS - Gross Unrealized Losses and Fair Value by Length of Time of Available-For-Sale Securities (Detail) $ in Thousands	Mar. 31, 2021USD ($)security	Dec. 31, 2020USD ($)security
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	90	34
Fair Value
Less Than 12 Months	$ 493,737	$ 92,868
12 Months or More	4,968	76,879
Total	498,705	169,747
Unrealized Losses
Less Than 12 Months	15,220	367
12 Months or More	9	693
Total	$ 15,229	$ 1,060
U.S. treasuries and government agencies
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	1	2
Fair Value
Less Than 12 Months	$ 4,972	$ 25,369
12 Months or More	0	0
Total	4,972	25,369
Unrealized Losses
Less Than 12 Months	2	2
12 Months or More	0	0
Total	$ 2	$ 2
State and municipal
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	43	8
Fair Value
Less Than 12 Months	$ 115,530	$ 22,753
12 Months or More	0	0
Total	115,530	22,753
Unrealized Losses
Less Than 12 Months	4,709	211
12 Months or More	0	0
Total	$ 4,709	$ 211
Mortgage-backed and asset-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities | security	46	24
Fair Value
Less Than 12 Months	$ 373,235	$ 44,746
12 Months or More	4,968	76,879
Total	378,203	121,625
Unrealized Losses
Less Than 12 Months	10,509	154
12 Months or More	9	693
Total	$ 10,518	$ 847

INVESTMENTS - Estimated fair va

INVESTMENTS - Estimated fair values of debt securities available-for-sale by contractual maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value
Total available-for-sale debt securities	$ 1,427,880	$ 1,348,021
Amortized Cost
Total available-for-sale debt securities	1,418,931	1,310,159
U.S. treasuries and government agencies
Fair Value
One year or less	36,904	33,963
One to five years	11,182	9,334
Five to ten years	0	0
After ten years	0	0
Total available-for-sale debt securities	48,086	43,297
Amortized Cost
One year or less	36,744	33,833
One to five years	10,897	8,917
Five to ten years	0	0
After ten years	0	0
Total available-for-sale debt securities	47,641	42,750
State and municipal
Fair Value
One year or less	13,175	16,581
One to five years	38,077	44,910
Five to ten years	49,417	59,059
After ten years	265,363	269,817
Total available-for-sale debt securities	366,032	390,367
Amortized Cost
One year or less	13,098	16,458
One to five years	36,965	43,857
Five to ten years	47,569	56,130
After ten years	265,183	260,663
Total available-for-sale debt securities	362,815	377,108
Mortgage-backed and asset-backed
Fair Value
One year or less	1,923	1
One to five years	20,180	21,637
Five to ten years	67,401	74,142
After ten years	916,675	808,652
Total available-for-sale debt securities	1,006,179	904,432
Amortized Cost
One year or less	1,905	1
One to five years	19,822	21,229
Five to ten years	66,718	72,481
After ten years	913,030	787,490
Total available-for-sale debt securities	1,001,475	881,201
Corporate debt
Fair Value
One year or less	0	0
One to five years	0	2,318
Five to ten years	7,583	7,607
After ten years	0	0
Total available-for-sale debt securities	7,583	9,925
Amortized Cost
One year or less	0	0
One to five years	0	2,100
Five to ten years	7,000	7,000
After ten years	0	0
Total available-for-sale debt securities	$ 7,000	$ 9,100

INVESTMENTS (Other Equity Secur

INVESTMENTS (Other Equity Securities) (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract]
Federal Reserve Bank stock	$ 34,028	$ 38,650
Federal Home Loan Bank of Atlanta stock	10,142	26,433
Marketable equity securities	677	677
Total equity securities	$ 44,847	$ 65,760

LOANS - Narrative (Detail)

LOANS - Narrative (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Net deferred loan fees	$ 30.3	$ 24.5
Paycheck Protection Program
Loans and Leases Receivable Disclosure [Line Items]
Net deferred loan fees	$ 27	$ 21.2

LOANS (Loan Portfolio Segment B

LOANS (Loan Portfolio Segment Balances) (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 10,446,866	$ 10,400,509
Commercial investor real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	3,652,418	3,634,720
Commercial owner-occupied real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,644,848	1,642,216
Commercial AD&C
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,051,013	1,050,973
Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,022,546	1,105,179
Residential construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	171,028	182,619
Commercial real estate: | Commercial investor real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	3,652,418	3,634,720
Commercial real estate: | Commercial owner-occupied real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,644,848	1,642,216
Commercial real estate: | Commercial AD&C
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,051,013	1,050,973
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	8,759,388	8,595,457
Commercial | Commercial business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	2,411,109	2,267,548
Residential real estate: | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,022,546	1,105,179
Residential real estate: | Residential construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	171,028	182,619
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	493,904	517,254
Total residential and consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 1,687,478	$ 1,805,052

CREDIT QUALITY ASSESSMENT - All

CREDIT QUALITY ASSESSMENT - Allowance for credit loss activity (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 165,367	$ 56,132	$ 56,132
Provision for credit losses	(34,708)	24,469	85,669
Loan charge-offs	(743)	(654)	(1,819)
Loan recoveries	445	108	1,012
Net charge-offs	(298)	(546)	(807)
Balance at period end	$ 130,361	85,800	165,367
Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		2,762	2,762
Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		$ 2,983	$ 2,983

CREDIT QUALITY ASSESSMENT - Col

CREDIT QUALITY ASSESSMENT - Collateral Dependent Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Credit Loss [Abstract]
Collateral dependent loans individually evaluated for credit loss with an allowance	$ 32,241	$ 20,717
Collateral dependent loans individually evaluated for credit loss without an allowance	49,757	77,001
Total individually evaluated collateral dependent loans	81,998	97,718
Allowance for credit losses related to loans evaluated individually	13,101	11,405
Allowance for credit losses related to loans evaluated collectively	117,260	153,962
Total allowance for credit losses	$ 130,361	$ 165,367	$ 85,800	$ 56,132

CREDIT QUALITY ASSESSMENT - A_2

CREDIT QUALITY ASSESSMENT - Allowance for Credit or Loan Losses by Respective Loan Portfolio Segment (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 165,367	$ 56,132	$ 56,132
Initial allowance on acquired Revere PCD loans			18,628
Provision/ (credit) for credit losses	(34,708)	24,469	85,669
Charge-offs	(743)	(654)	(1,819)
Recoveries	445	108	1,012
Net recoveries (charge-offs)	(298)	(546)	(807)
Balance at period end	130,361	85,800	165,367
Total loans	$ 10,446,866		$ 10,400,509
Allowance for credit losses to total loans ratio	1.25%		1.59%
Balance of loans individually evaluated for credit loss	$ 81,998		$ 97,718
Allowance related to loans evaluated individually	$ 13,101		$ 11,405
Individual allowance to loans evaluated individually ratio	15.98%		11.67%
Balance of loans collectively evaluated for credit loss	$ 10,364,868		$ 10,302,791
Allowance related to loans evaluated collectively	$ 117,260		$ 153,962
Collective allowance to loans evaluated collectively ratio	1.13%		1.49%
Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		2,762	$ 2,762
Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		2,983	2,983
Commercial investor real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Total loans	$ 3,652,418		3,634,720
Commercial owner-occupied real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Total loans	1,644,848		1,642,216
Commercial AD&C
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Total loans	1,051,013		1,050,973
Residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Total loans	1,022,546		1,105,179
Residential construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Total loans	171,028		182,619
Commercial real estate: | Commercial investor real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	57,404	18,407	18,407
Initial allowance on acquired Revere PCD loans			7,973
Provision/ (credit) for credit losses	(8,981)		33,431
Charge-offs	0		(411)
Recoveries	27		15
Net recoveries (charge-offs)	27		(396)
Balance at period end	48,450		57,404
Total loans	$ 3,652,418		$ 3,634,720
Allowance for credit losses to total loans ratio	1.33%		1.58%
Balance of loans individually evaluated for credit loss	$ 42,776		$ 45,227
Allowance related to loans evaluated individually	$ 2,988		$ 1,273
Individual allowance to loans evaluated individually ratio	6.99%		2.81%
Balance of loans collectively evaluated for credit loss	$ 3,609,642		$ 3,589,493
Allowance related to loans evaluated collectively	$ 45,462		$ 56,131
Collective allowance to loans evaluated collectively ratio	1.26%		1.56%
Commercial real estate: | Commercial investor real estate | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		1,114	$ 1,114
Commercial real estate: | Commercial investor real estate | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		(3,125)	(3,125)
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 20,061	6,884	6,884
Initial allowance on acquired Revere PCD loans			2,782
Provision/ (credit) for credit losses	(5,594)		10,008
Charge-offs	0		0
Recoveries	0		0
Net recoveries (charge-offs)	0		0
Balance at period end	14,467		20,061
Total loans	$ 1,644,848		$ 1,642,216
Allowance for credit losses to total loans ratio	0.88%		1.22%
Balance of loans individually evaluated for credit loss	$ 8,316		$ 11,561
Allowance related to loans evaluated individually	$ 0		$ 0
Individual allowance to loans evaluated individually ratio	0.00%		0.00%
Balance of loans collectively evaluated for credit loss	$ 1,636,532		$ 1,630,655
Allowance related to loans evaluated collectively	$ 14,467		$ 20,061
Collective allowance to loans evaluated collectively ratio	0.88%		1.23%
Commercial real estate: | Commercial owner-occupied real estate | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		0	$ 0
Commercial real estate: | Commercial owner-occupied real estate | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		387	387
Commercial real estate: | Commercial AD&C
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 22,157	7,590	7,590
Initial allowance on acquired Revere PCD loans			1,248
Provision/ (credit) for credit losses	760		10,743
Charge-offs	0		0
Recoveries	0		0
Net recoveries (charge-offs)	0		0
Balance at period end	22,917		22,157
Total loans	$ 1,051,013		$ 1,050,973
Allowance for credit losses to total loans ratio	2.18%		2.11%
Balance of loans individually evaluated for credit loss	$ 14,975		$ 15,044
Allowance related to loans evaluated individually	$ 603		$ 603
Individual allowance to loans evaluated individually ratio	4.03%		4.01%
Balance of loans collectively evaluated for credit loss	$ 1,036,038		$ 1,035,929
Allowance related to loans evaluated collectively	$ 22,314		$ 21,554
Collective allowance to loans evaluated collectively ratio	2.15%		2.08%
Commercial real estate: | Commercial AD&C | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		0	$ 0
Commercial real estate: | Commercial AD&C | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		2,576	2,576
Commercial Business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Total loans	$ 8,759,388		8,595,457
Balance of loans individually evaluated for credit loss	13,831		23,648
Allowance related to loans evaluated individually	9,510		9,529
Commercial Business | Commercial business
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	46,806	11,395	11,395
Initial allowance on acquired Revere PCD loans			6,289
Provision/ (credit) for credit losses	(14,343)		24,374
Charge-offs	(650)		(491)
Recoveries	16		702
Net recoveries (charge-offs)	(634)		211
Balance at period end	31,829		46,806
Total loans	$ 2,411,109		$ 2,267,548
Allowance for credit losses to total loans ratio	1.32%		2.06%
Balance of loans individually evaluated for credit loss	$ 13,831		$ 23,648
Allowance related to loans evaluated individually	$ 9,510		$ 9,529
Individual allowance to loans evaluated individually ratio	68.76%		40.30%
Balance of loans collectively evaluated for credit loss	$ 2,397,278		$ 2,243,900
Allowance related to loans evaluated collectively	$ 22,319		$ 37,277
Collective allowance to loans evaluated collectively ratio	0.93%		1.66%
Commercial Business | Commercial business | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		1,549	$ 1,549
Commercial Business | Commercial business | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		2,988	2,988
Residential real estate: | Residential mortgage
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 11,295	8,803	8,803
Initial allowance on acquired Revere PCD loans			243
Provision/ (credit) for credit losses	(4,018)		3,016
Charge-offs	0		(484)
Recoveries	270		105
Net recoveries (charge-offs)	270		(379)
Balance at period end	7,547		11,295
Total loans	$ 1,022,546		$ 1,105,179
Allowance for credit losses to total loans ratio	0.74%		1.02%
Balance of loans individually evaluated for credit loss	$ 1,737		$ 1,874
Allowance related to loans evaluated individually	$ 0		$ 0
Individual allowance to loans evaluated individually ratio	0.00%		0.00%
Balance of loans collectively evaluated for credit loss	$ 1,020,809		$ 1,103,305
Allowance related to loans evaluated collectively	$ 7,547		$ 11,295
Collective allowance to loans evaluated collectively ratio	0.74%		1.02%
Residential real estate: | Residential mortgage | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		0	$ 0
Residential real estate: | Residential mortgage | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		(388)	(388)
Residential real estate: | Residential construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 1,502	967	967
Initial allowance on acquired Revere PCD loans			6
Provision/ (credit) for credit losses	(849)		798
Charge-offs	0		0
Recoveries	0		6
Net recoveries (charge-offs)	0		6
Balance at period end	653		1,502
Total loans	$ 171,028		$ 182,619
Allowance for credit losses to total loans ratio	0.38%		0.82%
Balance of loans individually evaluated for credit loss	$ 0		$ 0
Allowance related to loans evaluated individually	$ 0		$ 0
Individual allowance to loans evaluated individually ratio	0.00%		0.00%
Balance of loans collectively evaluated for credit loss	$ 171,028		$ 182,619
Allowance related to loans evaluated collectively	$ 653		$ 1,502
Collective allowance to loans evaluated collectively ratio	0.38%		0.82%
Residential real estate: | Residential construction | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		0	$ 0
Residential real estate: | Residential construction | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		(275)	(275)
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 6,142	2,086	2,086
Initial allowance on acquired Revere PCD loans			87
Provision/ (credit) for credit losses	(1,683)		3,299
Charge-offs	(93)		(433)
Recoveries	132		184
Net recoveries (charge-offs)	39		(249)
Balance at period end	4,498		6,142
Total loans	$ 493,904		$ 517,254
Allowance for credit losses to total loans ratio	0.91%		1.19%
Balance of loans individually evaluated for credit loss	$ 363		$ 364
Allowance related to loans evaluated individually	$ 0		$ 0
Individual allowance to loans evaluated individually ratio	0.00%		0.00%
Balance of loans collectively evaluated for credit loss	$ 493,541		$ 516,890
Allowance related to loans evaluated collectively	$ 4,498		$ 6,142
Collective allowance to loans evaluated collectively ratio	0.91%		1.19%
Consumer | Revision of Prior Period, Reclassification, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		99	$ 99
Consumer | Revision of Prior Period, Accounting Standards Update, Adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period		$ 820	$ 820

CREDIT QUALITY ASSESSMENT - C_2

CREDIT QUALITY ASSESSMENT - Collateral dependent loans individually evaluated for credit loss (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	$ 32,241	$ 20,717
Allowance related to loans evaluated individually	13,101	11,405
Loans individually evaluated for credit loss without an allowance	49,757	77,001
Total individually evaluated collateral dependent loans	81,998	97,718
Total unpaid contractual principal balance	93,276	115,816
Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	28,862	17,419
Loans individually evaluated for credit loss without an allowance	44,726	71,764
Total individually evaluated collateral dependent loans	73,588	89,183
Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	2,806	2,709
Loans individually evaluated for credit loss without an allowance	3,333	3,509
Total individually evaluated collateral dependent loans	6,139	6,218
Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	573	589
Loans individually evaluated for credit loss without an allowance	1,698	1,728
Total individually evaluated collateral dependent loans	2,271	2,317
Commercial real estate: | Commercial investor real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	18,022	5,612
Allowance related to loans evaluated individually	2,988	1,273
Loans individually evaluated for credit loss without an allowance	24,754	39,615
Total individually evaluated collateral dependent loans	42,776	45,227
Total unpaid contractual principal balance	47,547	49,920
Commercial real estate: | Commercial investor real estate | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	17,686	4,913
Loans individually evaluated for credit loss without an allowance	24,754	39,615
Total individually evaluated collateral dependent loans	42,440	44,528
Commercial real estate: | Commercial investor real estate | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	336	699
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	336	699
Commercial real estate: | Commercial investor real estate | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	8,316	11,561
Total individually evaluated collateral dependent loans	8,316	11,561
Total unpaid contractual principal balance	10,306	15,309
Commercial real estate: | Commercial owner-occupied real estate | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	6,125	9,315
Total individually evaluated collateral dependent loans	6,125	9,315
Commercial real estate: | Commercial owner-occupied real estate | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	2,191	2,246
Total individually evaluated collateral dependent loans	2,191	2,246
Commercial real estate: | Commercial owner-occupied real estate | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial real estate: | Commercial AD&C
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	1,446	1,328
Allowance related to loans evaluated individually	603	603
Loans individually evaluated for credit loss without an allowance	13,529	13,716
Total individually evaluated collateral dependent loans	14,975	15,044
Total unpaid contractual principal balance	16,157	16,040
Commercial real estate: | Commercial AD&C | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	1,446	1,328
Loans individually evaluated for credit loss without an allowance	13,529	13,716
Total individually evaluated collateral dependent loans	14,975	15,044
Commercial real estate: | Commercial AD&C | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial real estate: | Commercial AD&C | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Commercial Business
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	12,773	13,777
Allowance related to loans evaluated individually	9,510	9,529
Loans individually evaluated for credit loss without an allowance	1,058	9,871
Total individually evaluated collateral dependent loans	13,831	23,648
Total unpaid contractual principal balance	16,088	30,958
Commercial Business | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	9,730	11,178
Loans individually evaluated for credit loss without an allowance	318	9,118
Total individually evaluated collateral dependent loans	10,048	20,296
Commercial Business | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	2,470	2,010
Loans individually evaluated for credit loss without an allowance	629	627
Total individually evaluated collateral dependent loans	3,099	2,637
Commercial Business | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	573	589
Loans individually evaluated for credit loss without an allowance	111	126
Total individually evaluated collateral dependent loans	684	715
Residential real estate: | Residential mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	1,737	1,874
Total individually evaluated collateral dependent loans	1,737	1,874
Total unpaid contractual principal balance	2,814	3,225
Residential real estate: | Residential mortgage | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Residential real estate: | Residential mortgage | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	150	272
Total individually evaluated collateral dependent loans	150	272
Residential real estate: | Residential mortgage | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	1,587	1,602
Total individually evaluated collateral dependent loans	1,587	1,602
Residential real estate: | Residential construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Total unpaid contractual principal balance	0	0
Residential real estate: | Residential construction | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Residential real estate: | Residential construction | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Residential real estate: | Residential construction | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Allowance related to loans evaluated individually	0	0
Loans individually evaluated for credit loss without an allowance	363	364
Total individually evaluated collateral dependent loans	363	364
Total unpaid contractual principal balance	364	364
Consumer | Non-accruing
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	0	0
Consumer | Non-accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	363	364
Total individually evaluated collateral dependent loans	363	364
Consumer | Accruing | Restructured
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for credit loss with an allowance	0	0
Loans individually evaluated for credit loss without an allowance	0	0
Total individually evaluated collateral dependent loans	$ 0	$ 0

CREDIT QUALITY ASSESSMENT - Non

CREDIT QUALITY ASSESSMENT - Non-accrual Loans (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	$ 104,183	$ 72,562
Contractual interest income due on non- accrual loans during the period	1,732	18,301
Commercial real estate: | Commercial investor real estate
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	44,002	26,849
Contractual interest income due on non- accrual loans during the period	649	6,547
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	9,939	6,605
Contractual interest income due on non- accrual loans during the period	185	2,741
Commercial real estate: | Commercial AD&C
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	15,010	4,267
Contractual interest income due on non- accrual loans during the period	256	4,505
Commercial Business
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	18,040	16,532
Contractual interest income due on non- accrual loans during the period	428	2,858
Residential real estate: | Residential mortgage
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	9,903	11,634
Contractual interest income due on non- accrual loans during the period	110	918
Residential real estate: | Residential construction
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	0	0
Contractual interest income due on non- accrual loans during the period	0	0
Consumer
Financing Receivable, Nonaccrual [Line Items]
Average non-accrual loans for the period	7,289	6,675
Contractual interest income due on non- accrual loans during the period	$ 104	$ 732

CREDIT QUALITY ASSESSMENT - Nar

CREDIT QUALITY ASSESSMENT - Narrative (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period increase (decrease)	$ 0	$ 0
Other real estate owned	1,354	1,455
Non-accrual status
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans placed on non-accrual	421	85,286
Restructured Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans restructured during the period	500	4,500
Individual reserves	300	1,000
Other real estate owned	$ 1,400	$ 1,500

CREDIT QUALITY ASSESSMENT - Inf

CREDIT QUALITY ASSESSMENT - Information on the credit quality of loan portfolio under the new CECL (Detail) - Non-accrual status - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 112,361	$ 38,632
PCD loans designed as non-accrual		13,084
Loans placed on non-accrual	421	85,286
Non-accrual balances transferred to OREO	0	(70)
Non-accrual balances charged-off	(699)	(1,394)
Net payments or draws	(16,028)	(21,201)
Non-accrual loans brought current	(55)	(1,976)
Balance at end of period	96,000	112,361
Commercial real estate: | Commercial investor real estate
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	45,227	8,437
PCD loans designed as non-accrual		9,544
Loans placed on non-accrual	0	37,882
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	(411)
Net payments or draws	(2,451)	(10,225)
Non-accrual loans brought current	0	0
Balance at end of period	42,776	45,227
Commercial real estate: | Commercial owner-occupied real estate
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	11,561	4,148
PCD loans designed as non-accrual		0
Loans placed on non-accrual	0	8,572
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	0
Net payments or draws	(3,245)	(1,059)
Non-accrual loans brought current	0	(100)
Balance at end of period	8,316	11,561
Commercial real estate: | Commercial AD&C
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	15,044	829
PCD loans designed as non-accrual		0
Loans placed on non-accrual	0	15,844
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	0
Net payments or draws	(69)	(1,629)
Non-accrual loans brought current	0	0
Balance at end of period	14,975	15,044
Commercial Business
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	22,933	8,450
PCD loans designed as non-accrual		2,539
Loans placed on non-accrual	84	17,442
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	(650)	(446)
Net payments or draws	(9,220)	(4,169)
Non-accrual loans brought current	0	(883)
Balance at end of period	13,147	22,933
Residential real estate: | Residential mortgage
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	10,212	12,661
PCD loans designed as non-accrual		8
Loans placed on non-accrual	140	1,485
Non-accrual balances transferred to OREO	0	(70)
Non-accrual balances charged-off	0	(416)
Net payments or draws	(759)	(2,598)
Non-accrual loans brought current	0	(858)
Balance at end of period	9,593	10,212
Residential real estate: | Residential construction
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	0	0
PCD loans designed as non-accrual		0
Loans placed on non-accrual	0	0
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	0	0
Net payments or draws	0	0
Non-accrual loans brought current	0	0
Balance at end of period	0	0
Consumer
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	7,384	4,107
PCD loans designed as non-accrual		993
Loans placed on non-accrual	197	4,061
Non-accrual balances transferred to OREO	0	0
Non-accrual balances charged-off	(49)	(121)
Net payments or draws	(284)	(1,521)
Non-accrual loans brought current	(55)	(135)
Balance at end of period	$ 7,193	$ 7,384

CREDIT QUALITY ASSESSMENT - Cre

CREDIT QUALITY ASSESSMENT - Credit Quality of Loan Portfolio, New (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Total	$ 10,446,866	$ 10,400,509
Performing loans:
Financing Receivable, Past Due [Line Items]
Current	10,296,660	10,226,191
Total performing loans	10,348,166	10,285,057
Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	96,000	112,361
Loans greater than 90 days past due	429	774
Restructured loans	2,271	2,317
Total non-performing loans	98,700	115,452
30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	41,925	46,812
60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	9,581	12,054
Commercial investor real estate
Financing Receivable, Past Due [Line Items]
Total	3,652,418	3,634,720
Commercial owner-occupied real estate
Financing Receivable, Past Due [Line Items]
Total	1,644,848	1,642,216
Commercial AD&C
Financing Receivable, Past Due [Line Items]
Total	1,051,013	1,050,973
Residential mortgage
Financing Receivable, Past Due [Line Items]
Total	1,022,546	1,105,179
Residential construction
Financing Receivable, Past Due [Line Items]
Total	171,028	182,619
Commercial real estate: | Commercial investor real estate
Financing Receivable, Past Due [Line Items]
Total	3,652,418	3,634,720
Commercial real estate: | Commercial investor real estate | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	3,587,859	3,571,184
Total performing loans	3,609,642	3,589,360
Commercial real estate: | Commercial investor real estate | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	42,776	45,227
Loans greater than 90 days past due	0	133
Restructured loans	0	0
Total non-performing loans	42,776	45,360
Commercial real estate: | Commercial investor real estate | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	17,870	14,046
Commercial real estate: | Commercial investor real estate | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	3,913	4,130
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Past Due [Line Items]
Total	1,644,848	1,642,216
Commercial real estate: | Commercial owner-occupied real estate | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	1,633,446	1,624,265
Total performing loans	1,636,532	1,630,655
Commercial real estate: | Commercial owner-occupied real estate | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	8,316	11,561
Loans greater than 90 days past due	0	0
Restructured loans	0	0
Total non-performing loans	8,316	11,561
Commercial real estate: | Commercial owner-occupied real estate | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	3,086	6,390
Commercial real estate: | Commercial owner-occupied real estate | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	0	0
Commercial real estate: | Commercial AD&C
Financing Receivable, Past Due [Line Items]
Total	1,051,013	1,050,973
Commercial real estate: | Commercial AD&C | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	1,031,055	1,033,057
Total performing loans	1,036,038	1,035,929
Commercial real estate: | Commercial AD&C | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	14,975	15,044
Loans greater than 90 days past due	0	0
Restructured loans	0	0
Total non-performing loans	14,975	15,044
Commercial real estate: | Commercial AD&C | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	4,983	29
Commercial real estate: | Commercial AD&C | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	0	2,843
Commercial Business
Financing Receivable, Past Due [Line Items]
Total	8,759,388	8,595,457
Commercial Business | Commercial business
Financing Receivable, Past Due [Line Items]
Total	2,411,109	2,267,548
Commercial Business | Commercial business | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	2,392,818	2,238,617
Total performing loans	2,397,247	2,243,739
Commercial Business | Commercial business | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	13,147	22,933
Loans greater than 90 days past due	31	161
Restructured loans	684	715
Total non-performing loans	13,862	23,809
Commercial Business | Commercial business | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	3,983	4,859
Commercial Business | Commercial business | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	446	263
Residential real estate: | Residential mortgage
Financing Receivable, Past Due [Line Items]
Total	1,022,546	1,105,179
Residential real estate: | Residential mortgage | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	997,837	1,073,963
Total performing loans	1,010,968	1,092,885
Residential real estate: | Residential mortgage | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	9,593	10,212
Loans greater than 90 days past due	398	480
Restructured loans	1,587	1,602
Total non-performing loans	11,578	12,294
Residential real estate: | Residential mortgage | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	9,593	16,213
Residential real estate: | Residential mortgage | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	3,538	2,709
Residential real estate: | Residential construction
Financing Receivable, Past Due [Line Items]
Total	171,028	182,619
Residential real estate: | Residential construction | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	170,365	182,557
Total performing loans	171,028	182,619
Residential real estate: | Residential construction | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	0	0
Loans greater than 90 days past due	0	0
Restructured loans	0	0
Total non-performing loans	0	0
Residential real estate: | Residential construction | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	601	0
Residential real estate: | Residential construction | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	62	62
Consumer
Financing Receivable, Past Due [Line Items]
Total	493,904	517,254
Consumer | Performing loans:
Financing Receivable, Past Due [Line Items]
Current	483,280	502,548
Total performing loans	486,711	509,870
Consumer | Non-performing loans:
Financing Receivable, Past Due [Line Items]
Non-accrual loans	7,193	7,384
Loans greater than 90 days past due	0	0
Restructured loans	0	0
Total non-performing loans	7,193	7,384
Consumer | 30-59 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	1,809	5,275
Consumer | 60-89 days | Performing loans:
Financing Receivable, Past Due [Line Items]
Past due	$ 1,622	$ 2,047

CREDIT QUALITY ASSESSMENT - I_2

CREDIT QUALITY ASSESSMENT - Information about credit quality indicator by year of origination (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
2021	$ 961,411	$ 3,305,720
2020	2,937,967	1,774,275
2019	1,646,238	1,179,845
2018	1,091,611	1,016,641
2017	961,954	866,898
Prior	1,896,722	1,242,626
Revolving Loans	950,963	1,014,504
Total	10,446,866	10,400,509
Commercial investor real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2021	204,744	922,059
2020	882,937	767,459
2019	715,618	466,934
2018	469,104	470,150
2017	458,689	470,019
Prior	892,482	504,568
Revolving Loans	28,844	33,531
Total	3,652,418	3,634,720
Commercial investor real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	194,465	910,426
2020	881,973	763,214
2019	707,450	448,406
2018	452,909	448,698
2017	429,839	469,077
Prior	876,375	498,384
Revolving Loans	28,844	33,531
Total	3,571,855	3,571,736
Commercial investor real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	10,000	11,044
2020	527	0
2019	1,993	4,879
2018	2,640	833
2017	701	269
Prior	2,646	27
Revolving Loans	0	0
Total	18,507	17,052
Commercial investor real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	279	589
2020	437	4,245
2019	6,175	13,649
2018	13,555	20,619
2017	28,149	673
Prior	13,461	6,157
Revolving Loans	0	0
Total	62,056	45,932
Commercial investor real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	0
2019	0	0
2018	0	0
2017	0	0
Prior	0	0
Revolving Loans	0	0
Total	0	0
Commercial owner-occupied real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2021	47,661	289,210
2020	290,210	389,393
2019	384,594	239,670
2018	228,156	197,841
2017	193,940	205,278
Prior	495,494	319,160
Revolving Loans	4,793	1,664
Total	1,644,848	1,642,216
Commercial owner-occupied real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	47,661	285,310
2020	287,070	385,058
2019	375,951	234,578
2018	222,539	192,634
2017	188,795	204,925
Prior	485,151	306,840
Revolving Loans	4,793	1,664
Total	1,611,960	1,611,009
Commercial owner-occupied real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	2,290
2020	1,871	0
2019	4,327	3,027
2018	3,586	4,742
2017	4,698	134
Prior	5,279	4,079
Revolving Loans	0	0
Total	19,761	14,272
Commercial owner-occupied real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	1,610
2020	1,269	4,335
2019	4,316	2,065
2018	2,031	465
2017	447	219
Prior	5,064	8,009
Revolving Loans	0	0
Total	13,127	16,703
Commercial owner-occupied real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	0
2019	0	0
2018	0	0
2017	0	0
Prior	0	232
Revolving Loans	0	0
Total	0	232
Commercial AD&C
Financing Receivable, Credit Quality Indicator [Line Items]
2021	175,861	488,781
2020	374,686	262,428
2019	245,642	149,703
2018	110,557	64,008
2017	60,779	2,932
Prior	2,843	2,357
Revolving Loans	80,645	80,764
Total	1,051,013	1,050,973
Commercial AD&C | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	174,120	485,631
2020	373,158	261,537
2019	244,751	149,703
2018	110,557	50,192
2017	47,150	89
Prior	0	2,357
Revolving Loans	80,645	80,764
Total	1,030,381	1,030,273
Commercial AD&C | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	639	1,711
2020	1,073	0
2019	0	0
2018	0	0
2017	0	0
Prior	0	0
Revolving Loans	0	0
Total	1,712	1,711
Commercial AD&C | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	1,102	1,439
2020	455	891
2019	891	0
2018	0	13,816
2017	13,629	2,843
Prior	2,843	0
Revolving Loans	0	0
Total	18,920	18,989
Commercial AD&C | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	0
2019	0	0
2018	0	0
2017	0	0
Prior	0	0
Revolving Loans	0	0
Total	0	0
Residential mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
2021	44,604	236,909
2020	218,269	85,106
2019	78,965	158,382
2018	130,593	188,970
2017	165,064	143,557
Prior	385,051	292,255
Revolving Loans	0	0
Total	1,022,546	1,105,179
Residential mortgage | 660-850
Financing Receivable, Credit Quality Indicator [Line Items]
2021	43,362	229,033
2020	209,544	74,054
2019	66,700	138,824
2018	113,850	172,493
2017	153,972	129,701
Prior	336,256	251,065
Revolving Loans	0	0
Total	923,684	995,170
Residential mortgage | 600-659
Financing Receivable, Credit Quality Indicator [Line Items]
2021	745	4,824
2020	4,962	7,706
2019	9,539	10,763
2018	8,498	11,719
2017	8,044	8,173
Prior	25,851	21,424
Revolving Loans	0	0
Total	57,639	64,609
Residential mortgage | 540-599
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	350
2020	1,445	1,238
2019	1,181	5,219
2018	5,063	2,608
2017	1,930	4,791
Prior	14,187	10,167
Revolving Loans	0	0
Total	23,806	24,373
Residential mortgage | less than 540
Financing Receivable, Credit Quality Indicator [Line Items]
2021	497	2,702
2020	2,318	2,108
2019	1,545	3,576
2018	3,182	2,150
2017	1,118	892
Prior	8,757	9,599
Revolving Loans	0	0
Total	17,417	21,027
Residential construction
Financing Receivable, Credit Quality Indicator [Line Items]
2021	27,097	115,201
2020	102,244	47,836
2019	23,802	14,543
2018	14,166	2,805
2017	1,248	2,062
Prior	2,107	0
Revolving Loans	364	172
Total	171,028	182,619
Residential construction | 660-850
Financing Receivable, Credit Quality Indicator [Line Items]
2021	27,097	112,604
2020	101,290	44,647
2019	21,059	14,543
2018	14,166	2,805
2017	1,248	1,693
Prior	1,738	0
Revolving Loans	364	172
Total	166,962	176,464
Residential construction | 600-659
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	1,743
2020	0	3,189
2019	2,743	0
2018	0	0
2017	0	0
Prior	369	0
Revolving Loans	0	0
Total	3,112	4,932
Residential construction | 540-599
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	0
2020	0	0
2019	0	0
2018	0	0
2017	0	369
Prior	0	0
Revolving Loans	0	0
Total	0	369
Residential construction | less than 540
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	854
2020	954	0
2019	0	0
2018	0	0
2017	0	0
Prior	0	0
Revolving Loans	0	0
Total	954	854
Commercial Business
Financing Receivable, Credit Quality Indicator [Line Items]
Total	8,759,388	8,595,457
Commercial Business | Commercial business
Financing Receivable, Credit Quality Indicator [Line Items]
2021	460,040	1,249,771
2020	1,066,322	215,623
2019	191,501	144,348
2018	133,497	89,205
2017	79,373	38,836
Prior	78,545	87,689
Revolving Loans	401,831	442,076
Total	2,411,109	2,267,548
Commercial Business | Commercial business | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2021	459,815	1,244,822
2020	1,059,494	208,682
2019	179,214	138,861
2018	129,096	86,830
2017	77,302	34,498
Prior	71,681	81,760
Revolving Loans	396,258	433,016
Total	2,372,860	2,228,469
Commercial Business | Commercial business | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	1,929
2020	2,043	1,382
2019	8,793	1,119
2018	1,063	708
2017	1,214	309
Prior	845	621
Revolving Loans	3,792	4,319
Total	17,750	10,387
Commercial Business | Commercial business | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2021	225	2,914
2020	4,785	4,564
2019	3,494	3,519
2018	3,338	1,631
2017	857	2,745
Prior	6,019	3,456
Revolving Loans	1,781	1,829
Total	20,499	20,658
Commercial Business | Commercial business | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	106
2020	0	995
2019	0	849
2018	0	36
2017	0	1,284
Prior	0	1,852
Revolving Loans	0	2,912
Total	0	8,034
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
2021	1,404	3,789
2020	3,299	6,430
2019	6,116	6,265
2018	5,538	3,662
2017	2,861	4,214
Prior	40,200	36,597
Revolving Loans	434,486	456,297
Total	493,904	517,254
Consumer | 660-850
Financing Receivable, Credit Quality Indicator [Line Items]
2021	1,054	2,575
2020	2,200	4,609
2019	4,263	5,112
2018	4,213	2,110
2017	1,567	2,614
Prior	27,406	24,444
Revolving Loans	400,050	417,737
Total	440,753	459,201
Consumer | 600-659
Financing Receivable, Credit Quality Indicator [Line Items]
2021	247	374
2020	265	445
2019	1,138	334
2018	484	428
2017	259	467
Prior	6,092	5,401
Revolving Loans	17,590	21,052
Total	26,075	28,501
Consumer | 540-599
Financing Receivable, Credit Quality Indicator [Line Items]
2021	0	89
2020	105	1,216
2019	564	294
2018	272	339
2017	270	601
Prior	3,425	3,926
Revolving Loans	6,938	6,153
Total	11,574	12,618
Consumer | less than 540
Financing Receivable, Credit Quality Indicator [Line Items]
2021	103	751
2020	729	160
2019	151	525
2018	569	785
2017	765	532
Prior	3,277	2,826
Revolving Loans	9,908	11,355
Total	$ 15,502	$ 16,934

CREDIT QUALITY ASSESSMENT - Res

CREDIT QUALITY ASSESSMENT - Restructured Loans at the date of Restructuring For Specific Segments of the Loan Portfolio (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 512	$ 4,533
Individual allowance	332	1,020
Restructured and subsequently defaulted	0	0
All Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	549
Individual allowance	0	0
Restructured and subsequently defaulted	0	0
Troubled debt restructurings:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	929
Restructured non-accruing	512	3,604
Troubled debt restructurings: | All Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	549
Restructured non-accruing	0	0
Commercial real estate: | Commercial investor real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	723
Individual allowance	0	65
Restructured and subsequently defaulted	0	0
Commercial real estate: | Commercial owner-occupied real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	930
Individual allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial real estate: | Commercial AD&C
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	0
Individual allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial real estate: | Troubled debt restructurings: | Commercial investor real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	723
Commercial real estate: | Troubled debt restructurings: | Commercial owner-occupied real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	930
Commercial real estate: | Troubled debt restructurings: | Commercial AD&C
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	0
Commercial Business
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	512	2,331
Individual allowance	332	955
Restructured and subsequently defaulted	0	0
Commercial Business | Troubled debt restructurings:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	380
Restructured non-accruing	$ 512	$ 1,951

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLE ASSETS - Gross Carrying Amounts and Accumulated Amortization (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 42,944	$ 42,944
Accumulated Amortization	(12,120)	(10,423)
Net Carrying Amount	30,824	32,521
Goodwill	370,223	370,223
Goodwill	370,223	370,223
Core deposit intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	29,038	29,038
Accumulated Amortization	(9,169)	(7,969)
Net Carrying Amount	$ 19,869	$ 21,069
Core deposit intangibles | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	8 years 2 months 12 days	8 years 4 months 24 days
Other identifiable intangibles
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 13,906	$ 13,906
Accumulated Amortization	(2,951)	(2,454)
Net Carrying Amount	$ 10,955	$ 11,452
Other identifiable intangibles | Weighted Average
Finite-Lived Intangible Assets [Line Items]
Weighted Average Remaining Life	10 years 6 months	10 years 8 months 12 days

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLE ASSETS (Net Carrying Amount of Goodwill By Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Goodwill [Roll Forward]
Beginning balance	$ 370,223
No Activity	0
Ending balance	370,223
Community Banking
Goodwill [Roll Forward]
Beginning balance	331,688
No Activity		$ 0
Ending balance	331,688
Insurance
Goodwill [Roll Forward]
Beginning balance	6,788
No Activity		0
Ending balance	6,788
Investment Management
Goodwill [Roll Forward]
Beginning balance	31,747
No Activity		$ 0
Ending balance	$ 31,747

GOODWILL AND OTHER INTANGIBLE_5

GOODWILL AND OTHER INTANGIBLE ASSETS (Estimated Future Amortization Expense for Amortizing Intangibles) (Detail) $ in Thousands	Mar. 31, 2021USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remaining 2021	$ 4,903
2022	5,844
2023	5,089
2024	4,333
2025	3,567
Thereafter	7,088
Total amortizing intangible assets	$ 30,824

DEPOSITS - Composition of Depos

DEPOSITS - Composition of Deposits (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Deposits [Abstract]
Noninterest-bearing deposits	$ 3,770,852	$ 3,325,547
Interest-bearing deposits:
Demand	1,395,209	1,292,164
Money market savings	3,371,400	3,339,645
Regular savings	465,125	418,051
Time deposits of less than $100,000	474,684	509,919
Time deposits greater than $100,000 and less than $250,000	774,668	670,717
Time deposits of $250,000 or more	425,814	477,026
Total interest-bearing deposits	6,906,900	6,707,522
Total deposits	$ 10,677,752	$ 10,033,069

BORROWINGS - Narrative (Detail)

BORROWINGS - Narrative (Detail) - USD ($)	Apr. 01, 2020	Nov. 05, 2019	Mar. 31, 2021	Dec. 31, 2020	Oct. 05, 2020
Debt Instrument [Line Items]
Long-term borrowings			$ 227,044,000	$ 227,088,000
Long-term debt			516,362,000	1,149,320,000
FHLB advances			100,000,000	379,100,000
Federal Home Loan Bank Advances
Debt Instrument [Line Items]
FHLB advances repaid			279,000,000
FHLB prepayment penalties			9,100,000
Maximum borrowing capacity			3,000,000,000	3,000,000,000
Federal Home Loan Bank Advances | Residential mortgage
Debt Instrument [Line Items]
Loans pledged as collateral			897,800,000	1,000,000,000
Federal Home Loan Bank Advances | Commercial real estate loans
Debt Instrument [Line Items]
Loans pledged as collateral			2,800,000,000	2,800,000,000
Federal Home Loan Bank Advances | Home equity lines of credit
Debt Instrument [Line Items]
Loans pledged as collateral			230,500,000	226,200,000
Federal Home Loan Bank Advances | Multifamily loans
Debt Instrument [Line Items]
Loans pledged as collateral			259,400,000	237,600,000
Federal Reserve and correspondent banks
Debt Instrument [Line Items]
Maximum borrowing capacity			420,400,000	276,200,000
Line of credit			0	0
Unsecured lines of credit, correspondent banks
Debt Instrument [Line Items]
Maximum borrowing capacity			1,100,000,000	1,100,000,000
Line of credit			60,000,000	390,000,000
Subordinated Debt
Debt Instrument [Line Items]
Add: Purchase accounting premium			1,552,000	$ 1,669,000
Subordinated Debt | Fixed Floating Rate Subordinated Notes
Debt Instrument [Line Items]
Long-term borrowings		$ 175,000,000
Interest rate		4.25%
Basis spread on variable rate		2.62%
Unamortized discount (premium) and debt issuance costs, net		$ 2,900,000
Subordinated Debt | WashingtonFirst Bankshares Inc
Debt Instrument [Line Items]
Long-term borrowings			$ 25,000,000
Interest rate			4.81%		6.00%
Basis spread on variable rate				4.57%
Add: Purchase accounting premium			$ 2,200,000
Debt instrument, term			10 years
Subordinated Debt | WashingtonFirst Bankshares Inc | Tier 2 Capital
Debt Instrument [Line Items]
Long-term borrowings			$ 20,000,000
Subordinated Debt | Revere acquisition
Debt Instrument [Line Items]
Long-term borrowings	$ 31,000,000
Interest rate	5.625%		5.625%
Basis spread on variable rate			4.41%
Add: Purchase accounting premium	$ 200,000
Debt instrument, term	10 years
Retail Repurchase Agreements
Debt Instrument [Line Items]
Long-term debt			$ 129,300,000	$ 153,200,000
Federal Funds Purchased
Debt Instrument [Line Items]
Long-term debt			60,000,000	$ 390,000,000
Federal funds under the PPPLF program
Debt Instrument [Line Items]
Long-term debt			0
Remaining borrowing capacity			$ 1,300,000,000

BORROWINGS - Schedule of Subord

BORROWINGS - Schedule of Subordinated Borrowing (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Oct. 05, 2020	Apr. 01, 2020
Subordinated Borrowing [Line Items]
Long-term borrowings	$ 227,044	$ 227,088
Subordinated Debt
Subordinated Borrowing [Line Items]
Subordinated debt, gross	231,000	231,000
Less: Debt held as investments by Sandy Spring	(3,000)	(3,000)
Add: Purchase accounting premium	1,552	1,669
Less: Debt issuance costs	(2,508)	(2,581)
Subordinated Debt | Fixed Floating
Subordinated Borrowing [Line Items]
Subordinated debt, gross	$ 175,000	175,000
Interest rate	4.25%
Subordinated Debt | WashingtonFirst Bankshares Inc
Subordinated Borrowing [Line Items]
Subordinated debt, gross	$ 25,000	25,000
Add: Purchase accounting premium	2,200
Long-term borrowings	$ 25,000
Interest rate	4.81%		6.00%
Subordinated Debt | Revere acquisition
Subordinated Borrowing [Line Items]
Subordinated debt, gross	$ 31,000	$ 31,000
Add: Purchase accounting premium				$ 200
Long-term borrowings				$ 31,000
Interest rate	5.625%			5.625%

STOCKHOLDERS' EQUITY - Narrativ

STOCKHOLDERS' EQUITY - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2018
Equity [Line Items]
Stock repurchased and retired (in shares)	820,328
Repurchase Plan 2020 | Common Stock
Equity [Line Items]
Number of shares authorized to be repurchased (in shares)		2,350,000
Repurchase Plan 2018 | Common Stock
Equity [Line Items]
Stock repurchased (in shares)	0
Shares available for issuance (in shares)			1,800,000
Stock repurchased and retired (in shares)	820,328	1,488,519
Stock repurchased and retired	$ 25.7	$ 50
Common stock repurchased, average price (in dollars per share)		$ 33.58

SHARE BASED COMPENSATION - Narr

SHARE BASED COMPENSATION - Narrative (Detail) - 2015 Omnibus Incentive Plan - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	May 06, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)			1,500,000
Shares available for issuance (in shares)	797,157
Expiration period	10 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period	7 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period	10 years
Stock Options and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized compensation expense	$ 0.9	$ 0.8
Restricted shares, Restricted stock units and Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 11.8
Expected cost recognition weighted average period	2 years 8 months 12 days
Shares issued (in shares)	119,329
Performance Shares | 3 Year Vesting Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	32,728
Performance period	3 years
Time Based Shares | 3 or 5 Year Vesting Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	86,601
Time Based Shares | 3 or 5 Year Vesting Period | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Stock Options | Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	0

SHARE BASED COMPENSATION - Summ

SHARE BASED COMPENSATION - Summary of Share Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Number of Common Shares
Beginning balance (in shares)	430,038
Granted (in shares)	0
Exercised (in shares)	(102,365)	(6,013)
Forfeited (in shares)	0
Expired (in shares)	0
Ending balance (in shares)	327,673		430,038
Exercisable at end of period (in shares)	322,908
Weighted Average Exercise Share Price
Beginning balance (in dollars per share)	$ 14.97
Granted (in dollars per share)	0
Exercised (in dollars per share)	14.96
Forfeited (in dollars per share)	0
Expired (in dollars per share)	0
Ending balance (in dollars per share)	14.98		$ 14.97
Exercisable at end of period (in dollars per share)	$ 14.63
Weighted Average Contractual Remaining Life (Years)
Balance at end of period	2 years 7 months 6 days		3 years
Exercisable at end of period	2 years 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract]
Beginning balance	$ 6,828
Exercised	2,381
Ending balance	9,045		$ 6,828
Exercisable at end of period	$ 9,017

SHARE BASED COMPENSATION - Su_2

SHARE BASED COMPENSATION - Summary of Activity Restricted Stock (Detail) - Restricted Stock	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Number of Common Shares/Units
Nonvested beginning balance (in shares) | shares	391,683
Granted (in shares) | shares	119,329
Vested (in shares) | shares	(13,669)
Forfeited (in shares) | shares	(3,988)
Nonvested ending balance (in shares) | shares	493,355
Weighted Average Grant-Date Fair Value
Nonvested beginning balance (in dollars per share) | $ / shares	$ 29.50
Granted (in dollars per share) | $ / shares	40.70
Vested (in dollars per share) | $ / shares	37.64
Forfeited (in dollars per share) | $ / shares	34.86
Nonvested ending balance (in dollars per share) | $ / shares	$ 31.94

PENSION PLAN (Net Periodic Bene

PENSION PLAN (Net Periodic Benefit Cost) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Retirement Benefits [Abstract]
Interest cost on projected benefit obligation	$ 318	$ 359
Expected return on plan assets	(312)	(456)
Recognized net actuarial loss	227	219
Net periodic benefit cost	$ 233	$ 122

PENSION PLAN - Narrative (Detai

PENSION PLAN - Narrative (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2021USD ($)
Retirement Benefits [Abstract]
Contributions by employer	$ 0

NET INCOME_ (LOSS) PER COMMON_2

NET INCOME/ (LOSS) PER COMMON SHARE (Calculation of Net Income per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net income	$ 75,464	$ 9,987
Distributed and undistributed earnings allocated to participating securities	(640)	(68)
Net income attributable to common shareholders	$ 74,824	$ 9,919
Total weighted average outstanding shares (in shares)	47,530,000	34,979,000
Less: weighted average participating securities (in shares)	(411,000)	(314,000)
Basic weighted average common shares (in shares)	47,119,000	34,665,000
Dilutive weighted average common stock equivalents (in shares)	296,000	78,000
Diluted weighted average common shares (in shares)	47,415,000	34,743,000
Basic net income per common share (in dollars per share)	$ 1.59	$ 0.29
Diluted net income per common share (in dollars per share)	$ 1.58	$ 0.28
Anti-dilutive shares (in shares)	3,000	9,000

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Net Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 18,705
Total other comprehensive income/ (loss)	(21,357)	$ 10,676
Ending Balance	(2,652)
Unrealized Gains on Investments Available-for-Sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	28,175	4,000
Other comprehensive loss before reclassification, net of tax	(21,478)	10,639
Reclassifications from accumulated other comprehensive income, net of tax	(43)	(127)
Total other comprehensive income/ (loss)	(21,521)	10,512
Ending Balance	6,654	14,512
Defined Benefit Pension Plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(9,470)	(8,332)
Other comprehensive loss before reclassification, net of tax	0	0
Reclassifications from accumulated other comprehensive income, net of tax	164	164
Total other comprehensive income/ (loss)	164	164
Ending Balance	(9,306)	(8,168)
Total
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	18,705	(4,332)
Other comprehensive loss before reclassification, net of tax	(21,478)	10,639
Reclassifications from accumulated other comprehensive income, net of tax	121	37
Total other comprehensive income/ (loss)	(21,357)	10,676
Ending Balance	$ (2,652)	$ 6,344

ACCUMULATED OTHER COMPREHENSI_4

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Reclassification Adjustments Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Unrealized gains/(losses) on investments available-for-sale Affected line item in the Statements of Income:
Investment securities gains	$ 58	$ 169
Income before taxes	58	169
Tax expense	(15)	(42)
Net income	43	127
Amortization of defined benefit pension plan items Affected line item in the Statements of Income:
Recognized actuarial loss	(227)	(219)
Loss before taxes	(227)	(219)
Tax benefit	63	55
Net loss	$ (164)	$ (164)

LEASES - Narrative (Details)

LEASES - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Lease liability	$ 74,219	$ 74,982
Operating lease ROU assets	$ 64,455	$ 65,215
Minimum
Lessee, Lease, Description [Line Items]
Renewal term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Renewal term	20 years
Lease operation commence in 2021
Lessee, Lease, Description [Line Items]
Lease liability	$ 1,900
Operating lease ROU assets	1,600
Tenant allowance	$ 200

LEASES - Lease Cost (Details)

LEASES - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Components of lease expense:
Operating lease cost (resulting from lease payments)	$ 3,151	$ 2,730
ROU assets obtained in the exchange for lease liabilities due to new leases and acquistions	$ 803	0
Weighted average remaining lease term of operating leases	9 years 4 months 24 days		9 years 6 months
Weighted average discount rate of operating leases	2.97%		3.04%
Supplemental cash flow information related to leases:
Operating cash flows from operating leases	$ 3,280	2,082
Operating lease ROU assets	64,455		$ 65,215
Lease liability	74,219		$ 74,982
Revere Bank And RPJ
Components of lease expense:
ROU assets obtained in the exchange for lease liabilities due to new leases and acquistions	$ 0	$ 311

LEASES - Maturities of operatin

LEASES - Maturities of operating lease liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
Remaining 2021	$ 9,346
2022	11,068
2023	11,054
2024	9,251
2025	7,537
Thereafter	38,522
Total undiscounted lease payments	86,778
Less: Present value discount	(12,559)
Lease liability	$ 74,219	$ 74,982

DERIVATIVES - Narrative (Detail

DERIVATIVES - Narrative (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Commercial Loan | Not Designated as Hedging Instrument | Interest rate swap agreements
Derivative [Line Items]
Notional amount	$ 374.7	$ 320.5

FAIR VALUE (Financial Assets an

FAIR VALUE (Financial Assets and Liabilities at Dates Indicated that Were Accounted for or Disclosed at Fair Value) (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	$ 1,427,880	$ 1,348,021
Residential mortgage loans held for sale (at fair value)	84,930	78,294
Residential Mortgage Loans Held For Sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale (at fair value)		75,500	$ 83,300
U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	48,086	43,297
State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	366,032	390,367
Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	1,006,179	904,432
Corporate debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	7,583	9,925
Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	1,427,880	1,348,021
Total assets	1,519,212	1,435,498
Total liabilities	(6,402)	(9,183)
Fair Value, Recurring | Residential Mortgage Loans Held For Sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	84,930	78,294
Fair Value, Recurring | U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	48,086	43,297
Fair Value, Recurring | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	366,032	390,367
Fair Value, Recurring | Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	1,006,179	904,432
Fair Value, Recurring | Corporate debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	7,583	9,925
Fair Value, Recurring | Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	6,402	9,183
Interest rate swap agreements	(6,402)	(9,183)
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Residential Mortgage Loans Held For Sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	0	0
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	0	0
Interest rate swap agreements	0	0
Fair Value, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	1,420,297	1,338,096
Total assets	1,511,629	1,425,573
Total liabilities	(6,402)	(9,183)
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Residential Mortgage Loans Held For Sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	84,930	78,294
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	48,086	43,297
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	366,032	390,367
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	1,006,179	904,432
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	6,402	9,183
Interest rate swap agreements	(6,402)	(9,183)
Fair Value, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	7,583	9,925
Total assets	7,583	9,925
Total liabilities	0	0
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Residential Mortgage Loans Held For Sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	0	0
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	0	0
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Corporate debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from sales of investment available-for-sale	7,583	9,925
Fair Value, Recurring | Significant Unobservable Inputs (Level 3) | Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	0	0
Interest rate swap agreements	$ 0	$ 0

FAIR VALUE (Change in the fair

FAIR VALUE (Change in the fair value of assets measured in the Condensed Consolidated Statements) (Detail) - Fair Value, Inputs, Level 3 - Investments available-for-sale: $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Investments available-for-sale:
Beginning balance	$ 9,925
Additions of Level 3 assets	0
Sales of Level 3 assets	(2,102)
Total unrealized loss included in other comprehensive income/ (loss)	(240)
Ending balance	$ 7,583

FAIR VALUE - Assets Measured at

FAIR VALUE - Assets Measured at Fair Value on Nonrecurring Basis (Detail) - Fair Value, Nonrecurring - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	$ 6,867	$ 15,356
Total Losses	(6,167)	(11,612)
Loans (1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	5,513	13,901
Total Losses	(5,780)	(11,326)
Other real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	1,354	1,455
Total Losses	(387)	(286)
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Loans (1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Other real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	0	0
Significant Other Observable Inputs (Level 2) | Loans (1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	0	0
Significant Other Observable Inputs (Level 2) | Other real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	0	0
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	6,867	15,356
Fair Value, Inputs, Level 3 | Loans (1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	5,513	13,901
Fair Value, Inputs, Level 3 | Other real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, nonrecurring	$ 1,354	$ 1,455

FAIR VALUE - Narrative (Details

FAIR VALUE - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Balance of loans individually evaluated for credit loss	$ 82	$ 97.7
Loans receivable, fair value	68.9	86.3
Allowance related to loans evaluated individually	$ 13.1	$ 11.4

FAIR VALUE - Carrying Amounts a

FAIR VALUE - Carrying Amounts and Fair Values of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial assets:
Residential mortgage loans held for sale (at fair value)	$ 84,930	$ 78,294
Investments available-for-sale	1,427,880	1,348,021
Loans, net of allowance	10,316,505	10,235,142
Accrued interest receivable	44,559	46,431
Financial liabilities:
Other deposits	10,677,752	10,033,069
Securities sold under retail repurchase agreements and federal funds purchased	189,318	543,157
Advances from FHLB	100,000	379,075
Subordinated debt	227,044	227,088
Carrying Amount
Financial assets:
Cash and cash equivalents	228,621	297,003
Residential mortgage loans held for sale (at fair value)	84,930	78,294
Investments available-for-sale (at fair value)	1,427,880	1,348,021
Equity securities	44,847	65,760
Loans, net of allowance	10,316,505	10,235,142
Interest rate swap agreements	6,402	9,183
Accrued interest receivable	44,559	46,431
Bank owned life insurance	127,567	126,887
Financial liabilities:
Time deposits	1,675,166	1,657,662
Other deposits	9,002,586	8,375,407
Securities sold under retail repurchase agreements and federal funds purchased	189,318	543,157
Advances from FHLB	100,000	379,075
Subordinated debt	227,044	227,088
Interest rate swap agreements	6,402	9,183
Accrued interest payable	4,019	3,254
Estimated Fair Value
Financial assets:
Cash and cash equivalents	228,621	297,003
Residential mortgage loans held for sale (at fair value)	84,930	78,294
Investments available-for-sale (at fair value)	1,427,880	1,348,021
Equity securities	44,847	65,760
Loans, net of allowance	10,339,985	10,336,355
Interest rate swap agreements	6,402	9,183
Accrued interest receivable	44,559	46,431
Bank owned life insurance	127,567	126,887
Financial liabilities:
Time deposits	1,687,100	1,674,112
Other deposits	9,002,586	8,375,407
Securities sold under retail repurchase agreements and federal funds purchased	189,318	543,157
Advances from FHLB	100,327	390,593
Subordinated debt	217,942	227,512
Interest rate swap agreements	6,402	9,183
Accrued interest payable	4,019	3,254
Quoted Prices in Active Markets for Identical Assets (Level 1) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	228,621	297,003
Residential mortgage loans held for sale (at fair value)	0	0
Investments available-for-sale (at fair value)	0	0
Equity securities	44,847	65,760
Loans, net of allowance	0	0
Interest rate swap agreements	0	0
Accrued interest receivable	44,559	46,431
Bank owned life insurance	0	0
Financial liabilities:
Time deposits	0	0
Other deposits	9,002,586	8,375,407
Securities sold under retail repurchase agreements and federal funds purchased	0	0
Advances from FHLB	0	0
Subordinated debt	0	0
Interest rate swap agreements	0	0
Accrued interest payable	4,019	3,254
Significant Other Observable Inputs (Level 2) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Residential mortgage loans held for sale (at fair value)	84,930	78,294
Investments available-for-sale (at fair value)	1,420,297	1,338,096
Equity securities	0	0
Loans, net of allowance	0	0
Interest rate swap agreements	6,402	9,183
Accrued interest receivable	0	0
Bank owned life insurance	127,567	126,887
Financial liabilities:
Time deposits	1,687,100	1,674,112
Other deposits	0	0
Securities sold under retail repurchase agreements and federal funds purchased	189,318	543,157
Advances from FHLB	100,327	390,593
Subordinated debt	0	0
Interest rate swap agreements	6,402	9,183
Accrued interest payable	0	0
Significant Unobservable Inputs (Level 3) | Estimated Fair Value
Financial assets:
Cash and cash equivalents	0	0
Residential mortgage loans held for sale (at fair value)	0	0
Investments available-for-sale		9,925
Investments available-for-sale (at fair value)	7,583
Equity securities	0	0
Loans, net of allowance	10,339,985	10,336,355
Interest rate swap agreements	0	0
Accrued interest receivable	0	0
Bank owned life insurance	0	0
Financial liabilities:
Time deposits	0	0
Other deposits	0	0
Securities sold under retail repurchase agreements and federal funds purchased	0	0
Advances from FHLB	0	0
Subordinated debt	217,942	227,512
Interest rate swap agreements	0	0
Accrued interest payable	$ 0	$ 0

SEGMENT REPORTING - Narrative (

SEGMENT REPORTING - Narrative (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)segment	Mar. 31, 2020USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment	3
Amortization of Intangible Assets	$ 1,697	$ 600
Community Banking
Segment Reporting Information [Line Items]
Amortization of Intangible Assets	1,200	400
Insurance
Segment Reporting Information [Line Items]
Amortization of Intangible Assets	0	0
Investment Management
Segment Reporting Information [Line Items]
Amortization of Intangible Assets	500	$ 200
Investment Management | West Financial and RPJ
Segment Reporting Information [Line Items]
Assets under management	$ 3,600,000

SEGMENT REPORTING (Operating Se

SEGMENT REPORTING (Operating Segments and Reconciliation of Information to Condensed Consolidated Financial Statements) (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Interest income	$ 114,261	$ 83,858
Interest expense	9,661	19,524
Provision/ (credit) for credit losses	(34,708)	24,469	$ 85,669
Non-interest income	28,866	18,168
Non-interest expense	68,173	47,746
Income before income tax expense	100,001	10,287
Income tax expense	24,537	300
Net income	75,464	9,987
Assets	12,873,366	8,929,602	$ 12,798,429
Inter-Segment Elimination
Segment Reporting Information [Line Items]
Interest income	(3)	(4)
Interest expense	(3)	(4)
Provision/ (credit) for credit losses	0	0
Non-interest income	(217)	(204)
Non-interest expense	(217)	(204)
Income before income tax expense	0	0
Income tax expense	0	0
Net income	0	0
Assets	(73,137)	(54,791)
Community Banking | Operating Segments
Segment Reporting Information [Line Items]
Interest income	114,261	83,857
Interest expense	9,664	19,528
Provision/ (credit) for credit losses	(34,708)	24,469
Non-interest income	21,725	13,977
Non-interest expense	63,695	44,655
Income before income tax expense	97,335	9,182
Income tax expense	23,838	1
Net income	73,497	9,181
Assets	12,878,311	8,917,849
Insurance | Operating Segments
Segment Reporting Information [Line Items]
Interest income	1	3
Interest expense	0	0
Provision/ (credit) for credit losses	0	0
Non-interest income	2,151	2,129
Non-interest expense	1,487	1,464
Income before income tax expense	665	668
Income tax expense	183	185
Net income	482	483
Assets	11,504	10,887
Investment Management | Operating Segments
Segment Reporting Information [Line Items]
Interest income	2	2
Interest expense	0	0
Provision/ (credit) for credit losses	0	0
Non-interest income	5,207	2,266
Non-interest expense	3,208	1,831
Income before income tax expense	2,001	437
Income tax expense	516	114
Net income	1,485	323
Assets	$ 56,688	$ 55,657

Uncategorized Items - sasr-2021

Label	Element	Value
Accounting Standards Update [Extensible List]	us-gaap_AccountingStandardsUpdateExtensibleList	us-gaap:AccountingStandardsUpdate201613Member