Randolph Bancorp (RNDB) 10-Q 6 May 21 2021 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Trading Symbol	RNDB
Entity Registrant Name	Randolph Bancorp, Inc.
Entity Central Index Key	0001667161
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Current Reporting Status	Yes
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Security Exchange Name	NASDAQ
Title of 12(b) Security	Common Stock, par value $.01 per share
Entity Incorporation, State or Country Code	MA
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding		5,305,881
Entity Shell Company	false
Entity File Number	001-37780
Entity Tax Identification Number	81-1844402
Entity Address, Address Line One	10 Cabot Place
Entity Address, City or Town	Stoughton
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02072
City Area Code	781
Local Phone Number	963-2100
Document Quarterly Report	true
Document Transition Report	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and due from banks	$ 3,453	$ 4,206
Interest-bearing deposits	51,497	9,568
Total cash and cash equivalents	54,950	13,774
Securities available for sale, at fair value	54,148	55,366
Loans held for sale, at fair value	93,176	119,112
Loans, net of allowance for loan losses of $6,563 in 2021 and $6,784 in 2020	491,983	483,644
Federal Home Loan Bank of Boston stock, at cost	3,576	3,576
Accrued interest receivable	1,501	1,562
Mortgage servicing rights, net	14,744	12,377
Premises and equipment, net	4,709	4,781
Bank-owned life insurance	8,662	8,622
Foreclosed real estate	132	132
Other assets	10,607	18,126
Total assets	738,188	721,072
Deposits:
Non-interest bearing	118,623	96,731
Interest bearing	409,410	399,847
Brokered	32,225	31,729
Total deposits	560,258	528,307
Federal Reserve Bank advances		11,431
Federal Home Loan Bank of Boston advances	60,024	61,895
Mortgagors' escrow accounts	1,924	2,338
Post-employment benefit obligations	2,235	2,382
Other liabilities	12,888	14,900
Total liabilities	637,329	621,253
Commitments and contingencies (Note 14)
Stockholders' Equity:
Preferred stock, no par value; authorized: 1,000,000 shares; issued: none
Common stock, $.01 par value; authorized: 15,000,000 shares; issued and outstanding: 5,364,240 shares at March 31, 2021 and 5,495,514 shares at December 31, 2020	53	54
Additional paid-in capital	48,613	50,937
Retained earnings	55,801	51,689
ESOP-Unearned compensation	(3,709)	(3,756)
Accumulated other comprehensive income, net of tax	101	895
Total stockholders' equity	100,859	99,819
Total liabilities and stockholders' equity	$ 738,188	$ 721,072

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Loans, allowance for loan losses	$ 6,563	$ 6,784
Preferred stock, par value	$ 0	$ 0
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	15,000,000	15,000,000
Common stock, shares issued	5,364,240	5,495,514
Common stock, shares outstanding	5,364,240	5,495,514

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Interest and dividend income:
Loans	$ 5,508	$ 5,620
Securities-taxable	240	370
Securities-tax exempt	6	7
Interest-bearing deposits and certificates of deposit	7	56
Total interest and dividend income	5,761	6,053
Interest expense:
Deposits	438	1,425
Federal Reserve Bank and Federal Home Loan Bank of Boston advances	232	203
Total interest expense	670	1,628
Net interest income	5,091	4,425
Provision (credit) for loan losses	(213)	724
Net interest income after provision (credit) for loan losses	5,304	3,701
Non-interest income:
Customer service fees	367	306
Gain on loan origination and sale activities, net	10,993	7,144
Mortgage servicing fees, net	779	(1,254)
Increase in cash surrender value of life insurance	40	45
Other	244	210
Total non-interest income	12,423	6,451
Non-interest expenses:
Salaries and employee benefits	8,437	8,126
Occupancy and equipment	744	698
Data processing	263	196
Professional fees	561	405
Marketing	170	152
FDIC insurance	54	56
Other	1,722	1,326
Total non-interest expenses	11,951	10,959
Income (loss) before income taxes	5,776	(807)
Income tax expense	1,664	11
Net income (loss)	$ 4,112	$ (818)
Earnings (loss) per common share
Basic	$ 0.81	$ (0.16)
Diluted	$ 0.78	$ (0.16)
Weighted average shares outstanding
Basic	5,056,165	5,158,294
Diluted	5,254,907	5,158,294

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Net income (loss)		$ 4,112	$ (818)
Securities available for sale:
Unrealized holding gains (losses)		(917)	1,564
Related tax effects		119	0
Net-of-tax amount		(798)	1,564
Related tax effects		0	0
Net-of-tax amount		4	(3)
Total other comprehensive income (loss)		(794)	1,561
Comprehensive income		3,318	743
Supplemental Retirement Plan [Member]
Securities available for sale:
Actuarial losses	[1]	12	9
Prior service credits	[1]	(8)	(12)
Net change in supplemental retirement plan		$ 4	$ (3)
[1]	Amounts are included in other non-interest expenses in the consolidated statements of operations.

Consolidated Statements Changes

Consolidated Statements Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Unearned Compensation ESOP [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance at Dec. 31, 2019	$ 78,462	$ 56	$ 51,127	$ 31,757	$ (3,944)	$ (534)
Beginning balance, shares at Dec. 31, 2019		5,576,855
Net income (loss)	(818)			(818)
Other comprehensive income (loss)	1,561					1,561
Stock repurchased	(1,195)	$ (1)	(1,194)
Stock repurchased, shares		(98,800)
Restricted stock awards forfeited, shares		(7,251)
Share redemption for tax withholdings for restricted stock vesting	(53)		(53)
Share redemption for tax with holdings for restricted stock vesting, shares		(4,460)
Stock-based compensation	931		931
ESOP shares committed to be released	68		21		47
Ending balance at Mar. 31, 2020	78,956	$ 55	50,832	30,939	(3,897)	1,027
Ending balance, shares at Mar. 31, 2020		5,466,344
Beginning balance at Dec. 31, 2019	78,462	$ 56	51,127	31,757	(3,944)	(534)
Beginning balance, shares at Dec. 31, 2019		5,576,855
Ending balance at Dec. 31, 2020	99,819	$ 54	50,937	51,689	(3,756)	895
Ending balance, shares at Dec. 31, 2020		5,495,514
Net income (loss)	4,112			4,112
Other comprehensive income (loss)	(794)					(794)
Stock repurchased	(2,652)	$ (1)	(2,651)
Stock repurchased, shares		(130,295)
Share redemption for tax withholdings for restricted stock vesting	(3)		(3)
Share redemption for tax with holdings for restricted stock vesting, shares		(173)
Stock-based compensation	283		283
ESOP shares committed to be released	94		47		47
ESOP shares committed to be released, shares		(806)
Ending balance at Mar. 31, 2021	$ 100,859	$ 53	$ 48,613	$ 55,801	$ (3,709)	$ 101
Ending balance, shares at Mar. 31, 2021		5,364,240

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net income (loss)	$ 4,112,000	$ (818,000)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Provision (credit) for loan losses	(213,000)	724,000
Loans originated for sale	(487,808,000)	(219,471,000)
Net gain on sales of mortgage loans	(10,993,000)	(5,825,000)
Proceeds from sales of mortgage loans	515,419,000	229,579,000
Net amortization of securities	95,000	54,000
Net change in deferred loan costs and fees, and purchase premiums	339,000	3,000
Depreciation and amortization	182,000	218,000
Stock-based compensation	283,000	931,000
ESOP expense	94,000	68,000
Increase in cash surrender value of life insurance	(40,000)	(45,000)
Net (increase) decrease in mortgage servicing rights	(2,366,000)	1,068,000
Other, net	9,293,000	(2,908,000)
Net cash provided by operating activities	28,397,000	3,578,000
Securities available for sale:
Purchases	(3,913,000)
Calls/maturities		1,000,000
Principal payments on mortgage-backed securities	4,119,000	2,548,000
Loan originations, net of principal repayments	(2,900,000)	(6,435,000)
Loan purchases		(1,519,000)
Purchases of Federal Home Loan Bank of Boston stock		(456,000)
Purchases of premises and equipment	(110,000)	(137,000)
Net cash used in investing activities	(2,804,000)	(4,999,000)
Cash flows from financing activities:
Net increase in non-brokered deposits	31,455,000	12,884,000
Net increase (decrease) in brokered deposits	496,000	(4,907,000)
Net decrease in Federal Reserve Bank borrowings	(11,431,000)
Net decrease in short-term Federal Home Loan Bank of Boston borrowings		(19,822,000)
Issuance of long-term Federal Home Loan Bank of Boston advances		27,432,000
Repayments of long-term Federal Home Loan Bank of Boston advances	(1,871,000)
Net increase (decrease) in mortgagors' escrow accounts	(414,000)	22,000
Repurchases of common stock	(2,652,000)	(1,195,000)
Net cash provided by financing activities	15,583,000	14,414,000
Net change in cash and cash equivalents	41,176,000	12,993,000
Cash and cash equivalents at beginning of period	13,774,000	8,252,000
Cash and cash equivalents at end of period	54,950,000	21,245,000
Supplemental cash flow information:
Interest paid on deposits and borrowed funds	794,000	1,728,000
Income taxes paid	655,000	225,000
Non-cash item:
Transfer of held for sale loans to portfolio	5,565,000
Transfer of portfolio loan to foreclosed real estate		$ 132,000
Initial recognition of operating lease at commencement	$ 1,310,000

Basis of Financial Statement Pr

Basis of Financial Statement Presentation	3 Months Ended
	Mar. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Financial Statement Presentation	1. BASIS OF FINANCIAL STATEMENT PRESENTATION The unaudited consolidated financial statements include the accounts of Randolph Bancorp, Inc. (“Bancorp”) and its wholly-owned subsidiary, Envision Bank (the “Bank”, together with Bancorp, the “Company”). The Bank has subsidiaries involved in owning investment securities and foreclosed real estate properties and a subsidiary which provides loan closing services. All intercompany accounts and transactions have been eliminated in consolidation. These unaudited financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) for interim financial reporting and with the instructions to Form 10-Q and Article 10 of Regulation S-X issued by the Securities and Exchange Commission (“SEC”). Accordingly, the accompanying interim financial statements do not include all information required under GAAP for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation of the financial statements, primarily consisting of normal recurring adjustments, have been included. The operating results for the three months ended March 31, 2021 are not necessarily indicative of the results to be expected for the year ending December 31, 2021 or any other interim period. For further information, refer to the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, as filed with the SEC.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2021
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	2. RECENT ACCOUNTING PRONOUNCEMENTS In February 2016, FASB issued ASU 2016-02, Leases In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses

Global Pandemic Affecting Rando

Global Pandemic Affecting Randolph Bancorp, Inc.	3 Months Ended
	Mar. 31, 2021
Risks And Uncertainties [Abstract]
Global Pandemic Affecting Randolph Bancorp, Inc.	3. GLOBAL PANDEMIC AFFECTING RANDOLPH BANCORP, INC. On March 13, 2020, the United States Government declared a national emergency in response to the coronavirus (“COVID-19”) outbreak. The COVID-19 pandemic has caused, among other things, widespread shutdowns of businesses and volatile markets and has severely disrupted normal economic activity in the region the Company serves as well as across the nation. The following summarizes the more significant financial repercussions of this national emergency for the Company. Credit Quality and Allowance for Loan Losses The Company increased the allowance for loan losses during 2020 directly related to its estimate, based on available information, of probable incurred losses resulting from the impact of the COVID-19 pandemic. During the first quarter of 2021, the Company decreased part of the allowance for loan losses, based on available information, due to improving conditions relating to the COVID-19 pandemic. As the Company acquires additional information on overall economic prospects together with further assessments of the impact on individual borrowers, the loss estimated will be revised as needed, and these revisions could be material. The Company’s approach to estimating the impact of this pandemic on credit quality is presented in Note 6 – “Loans and Allowance for Loan Losses.” Disaster Response Plan Costs The Company implemented its disaster response plans when the national emergency was declared and a stay at home order was issued in the Commonwealth of Massachusetts. To operate in this mode the Company incurred expenses for, among other things, compensation for front-line and quarantined employees, buying equipment for a remote workforce, cleaning of office and branch buildings, and communications with customers regarding the status of the Company’s operations. These plan costs were immaterial for first quarter of 2021 and 2020, respectively. Loan Payment Deferral and Paycheck Protection Program In response to the pandemic’s effect on our customers, the Company implemented a series of measures through the date of this report, including participation in the Small Business Administration’s (“SBA”) Paycheck Protection Program (the “PPP”) and granting payment deferrals for residential mortgage, home equity and certain commercial borrowers who were current in their payments. The table below summarizes the lending activity and outstanding balances of PPP loans and the associated pledges to the Federal Reserve Bank’s (“FRB”) Paycheck Protection Program Liquidity Facility (“PPPLF”): PPP Loan Balance FRB Advances PPP Loans Outstanding at Amount Pledged Outstanding at Originated March 31, 2021 to PPPLF March 31, 2021 (1) (In thousands) 2020 PPP loans $ 15,387 $ 4,557 $ 15,387 $ - 2021 PPP loans 10,160 10,160 - - Total Activity $ 25,547 $ 14,717 $ 15,387 $ - (1) FRB advances were fully repaid during the first quarter of 2021 and the associated PPP loans are no longer pledged. T In accordance with interagency guidance issued in March 2020 and/or the CARES Act enacted in March 2020 and as modified by the Consolidated Appropriations Act, these short-term deferrals are not considered troubled debt restructurings, provided the loan modification is made between March 1, 2020 and as modified by the Consolidated Appropriations Act, the earlier of January 1, 2022 or 60 days after the end of the coronavirus emergency declaration and the applicable loan was not more than 30 days past due as of December 31, 2019. The Company has agreed to loan payment deferrals on commercial loans totaling $38.2 million, residential real estate loans in portfolio totaling $20.4 million and residential real estate loans serviced for others totaling $66.0 million as of March 31, 2021. The commercial loan payment deferrals are concentrated in the hotel and hospitality, restaurant and retail service industries. The qualifying residential real estate and commercial loan borrowers were required to contact the Company to receive the loan deferrals. The table below summarizes the status of the bank’s loan deferral activity: Status of Deferrals Granted Currently Outstanding Paid Off Deferrals Suspended/ Resumed Full Granted (1) Reduced Payment (2) Payment (2) Payoff (3) (In thousands) March 31, 2021 Real estate loans: Residential: One- to four-family $ 16,793 $ 4,316 $ 9,107 $ 3,370 Home equity loans and lines of credit 3,168 423 1,479 1,266 Construction 350 - 350 - Commercial 34,616 6,241 24,628 3,747 Total real estate loans 54,927 10,980 35,564 8,383 Commercial and industrial 3,579 - 1,569 2,010 Consumer 68 38 30 - Total $ 58,574 $ 11,018 $ 37,163 $ 10,393 December 31, 2020 Real estate loans: Residential: One- to four-family $ 15,514 $ 12,974 $ 2,109 $ 431 Home equity loans and lines of credit 3,179 626 1,287 1,266 Construction 350 350 - - Commercial 34,754 6,544 25,406 2,804 Total real estate loans 53,797 20,494 28,802 4,501 Commercial and industrial 3,645 - 1,635 2,010 Consumer 68 68 - - Total $ 57,510 $ 20,562 $ 30,437 $ 6,511 (1) This column equals the current outstanding balance of loans that received a deferral, plus the balance of loans that were deferred and were paid off in full. (2) These two columns are the current balance of all loans that received a deferral. The Suspended/Reduced Payment columns represents loans currently in a deferral period and the Resumed Payment columns represents loans that are no longer in a deferral period and have resumed normal payment. (3) This column represents the balance of deferred loans that were paid off in full. The payment deferral programs were applied prospectively from the respective dates of the events and did not change the delinquency status of the loans as of such dates. Accordingly, if all payments were current at the date of the event, the loan will not be reported as past due during the deferral period. Furthermore, for loans subject to the deferral programs on which payments were past due prior to the event, the delinquency status of such loans was frozen to the status that existed at the date of the event until the end of the deferral period. Accordingly, the table below summarizes the risk rating and for all loans that were granted deferral and are outstanding, and any loans that were listed in nonaccrual status at the dates indicated: Currently Outstanding Deferred Loans by Risk Rating Pass Rated / Special Sub- Non- Not Rated (1) Mention (1) standard (1) accrual (2) (In thousands) March 31, 2021 Real estate loans: Residential: One- to four-family $ 13,228 $ 195 $ - $ 195 Home equity loans and lines of credit 1,902 - - - Construction 350 - - - Commercial 17,985 7,649 5,235 5,235 Total real estate loans 33,465 7,844 5,235 5,430 Commercial and industrial 1,159 410 - - Consumer 68 - - - Total $ 34,692 $ 8,254 $ 5,235 $ 5,430 December 31, 2020 Real estate loans: Residential: One- to four-family $ 14,887 $ 196 $ - $ 196 Home equity loans and lines of credit 1,913 - - - Construction 350 - - - Commercial 19,020 8,748 4,182 4,182 Total real estate loans 36,170 8,944 4,182 4,378 Commercial and industrial 1,204 431 - - Consumer 68 - - - Total $ 37,442 $ 9,375 $ 4,182 $ 4,378 (1) These three columns indicate the risk rating and subsequent outstanding balance of loans that have received a deferral. The Pass Rated/Not Rated, Special Mention and Substandard columns reconcile to the Suspended Payment/Reduced Payment and Resumed Payment columns in the preceding table. (2) Nonaccrual loans are risk rated as either special mention or substandard loans and are included as a balance in those columns.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Accumulated Other Comprehensive Income (Loss)	4 . ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income (loss). Although certain changes in assets and liabilities are reported as a separate component of stockholders’ equity, such items, along with net income (loss), are components of comprehensive income (loss). The components of accumulated other comprehensive income (loss), included in total stockholders’ equity, are as follows: March 31, December 31, 2021 2020 (In thousands) Securities available for sale: Net unrealized gain $ 795 $ 1,713 Tax effect (193 ) (313 ) Net-of-tax amount 602 1,400 Supplemental retirement plan Unrecognized net actuarial loss (700 ) (712 ) Unrecognized net prior service credit 246 254 (454 ) (458 ) Tax effect (47 ) (47 ) Net-of-tax amount (501 ) (505 ) Accumulated other comprehensive income (loss) $ 101 $ 895

Securities Available for Sale

Securities Available for Sale	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Securities Available for Sale	5 . SECURITIES AVAILABLE FOR SALE The amortized cost and fair value of securities available for sale, including gross unrealized gains and losses, are as follows: Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value (In thousands) March 31, 2021 Debt securities: U.S. Treasury $ 3,913 $ — $ (90 ) $ 3,823 U.S. Government-sponsored enterprises 1,993 — (2 ) 1,991 Corporate 4,286 15 (5 ) 4,296 Municipal 595 3 — 598 Residential mortgage-backed securities: U.S. Government-sponsored enterprises 29,023 623 (220 ) 29,426 Commercial mortgage-backed securities: U.S. Government-sponsored enterprises 8,825 361 — 9,186 U.S. Government-guaranteed 559 9 — 568 Collateralized mortgage obligations: U.S. Government-sponsored enterprises 944 41 — 985 U.S. Government-guaranteed 3,215 60 — 3,275 Total securities available for sale $ 53,353 $ 1,112 $ (317 ) $ 54,148 December 31, 2020 Debt securities: U.S. Government-sponsored enterprises $ 1,993 $ 3 $ — $ 1,996 Corporate 4,300 56 — 4,356 Municipal 595 5 — 600 Residential mortgage-backed securities: U.S. Government-sponsored enterprises 32,538 919 — 33,457 Commercial mortgage-backed securities: U.S. Government-sponsored enterprises 8,857 525 — 9,382 U.S. Government-guaranteed 977 24 — 1,001 Collateralized mortgage obligations: U.S. Government-sponsored enterprises 996 52 — 1,048 U.S. Government-guaranteed 3,398 128 — 3,526 Total securities available for sale $ 53,654 $ 1,712 $ — $ 55,366 There were no sales of securities during the three months ended March 31, 2021 and 2020. The amortized cost and fair value of debt securities by contractual maturity at March 31, 2021 are presented below. Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Amortized Fair Cost Value (In thousands) Within 1 year $ 1,001 $ 1,011 After 1 year through 5 years 4,804 4,811 After 5 years through 10 years 4,982 4,886 10,787 10,708 Mortgage-backed securities 42,566 43,440 $ 53,353 $ 54,148 Information pertaining to securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous loss position, follows: Less Over Twelve Months Gross Gross Unrealized Fair Unrealized Fair Losses Value Losses Value March 31, 2021 (In thousands) Debt securities: U.S. Treasury $ (90 ) $ 3,823 $ — $ — U.S. Government-sponsored enterprises (2 ) 1,992 — — Corporate (5 ) 1,801 — — Residential mortgage-backed securities U.S. Government-sponsored enterprises (220 ) 10,356 — — Total debt securities $ (317 ) $ 17,972 $ — $ — There were no securities in a loss position at December 31, 2020. At March 31, 2021, eleven debt securities had unrealized losses with aggregate depreciation of 1.73% from the Company’s amortized cost basis. The unrealized losses at March 31, 2021 were due to interest rate increases since the date on which they were purchased. The Company currently does not believe it is probable that it will be unable to collect all amounts due according to the contractual terms of these investments. Therefore, it is expected that the securities would not be settled at a price less than the par value of the investment. Because the Company does not intend to sell any debt securities and it is more likely than not that the Company will not be required to sell any debt securities before recovery of its amortized cost basis, it does not consider these investments to be other-than-temporarily impaired at March 31, 2021.

Loans and Allowance for Loan Lo

Loans and Allowance for Loan Losses	3 Months Ended
	Mar. 31, 2021
Receivables [Abstract]
Loans and Allowance for Loan Losses	6 . LOANS AND ALLOWANCE FOR LOAN LOSSES A summary of the loan portfolio is as follows: March 31, 2021 December 31, 2020 (In thousands) Real estate loans: Residential: One- to four-family $ 239,190 $ 235,648 Home equity loans and lines of credit 49,073 48,166 Commercial 146,930 143,893 Construction 29,975 31,050 465,168 458,757 Commercial and industrial 23,869 20,259 Consumer 8,724 10,289 Total loans 497,761 489,305 Allowance for loan losses (6,563 ) (6,784 ) Net deferred loan costs and fees, and purchase premiums 785 1,123 $ 491,983 $ 483,644 The following tables present activity in the allowance for loan losses by loan category for the three months ended March 31, 2021 and 2020, and allocation of the allowance to each category as of March 31, 2021 and December 31, 2020: Residential 1-4 Family Second Mortgages and HELOC Commercial Real Estate Construction Commercial and Industrial Consumer Total (In thousands) Three Months Ended March 31, 2021 Allowance at December 31, 2020 $ 1,646 $ 442 $ 3,402 $ 751 $ 416 $ 127 $ 6,784 Provision (credit) for loan losses (126 ) (17 ) (12 ) (31 ) (15 ) (12 ) (213 ) Loans charged-off — — — — — (10 ) (10 ) Recoveries 2 — — — — — 2 Balance at March 31, 2021 $ 1,522 $ 425 $ 3,390 $ 720 $ 401 $ 105 $ 6,563 Three Months Ended March 31, 2020 Allowance at December 31, 2019 $ 1,096 $ 289 $ 1,840 $ 692 $ 235 $ 128 $ 4,280 Provision for loan losses 123 54 401 80 45 21 724 Loans charged-off — — — — — (16 ) (16 ) Recoveries 4 — — — — 4 8 Balance at March 31, 2020 $ 1,223 $ 343 $ 2,241 $ 772 $ 280 $ 137 $ 4,996 Additional information pertaining to the allowance for loan losses at March 31, 2021 and December 31, 2020 is as follows: Residential 1-4 Family Second Mortgages and HELOC Commercial Real Estate Construction Commercial and Industrial Consumer Total March 31, 2021 (In thousands) Allowance for impaired loans $ 132 $ — $ 17 $ — $ — $ — $ 149 Allowance for non-impaired loans 1,390 425 3,373 720 401 105 6,414 Total allowance for loan losses $ 1,522 $ 425 $ 3,390 $ 720 $ 401 $ 105 $ 6,563 Impaired loans $ 3,845 $ 423 $ 5,779 $ — $ — $ — $ 10,047 Non-impaired loans 235,345 48,650 141,151 29,975 23,869 8,724 487,714 Total loans $ 239,190 $ 49,073 $ 146,930 $ 29,975 $ 23,869 $ 8,724 $ 497,761 December 31, 2020 Allowance for impaired loans $ 133 $ — $ — $ — $ — $ — $ 133 Allowance for non-impaired loans 1,513 442 3,402 751 416 127 6,651 Total allowance for loan losses $ 1,646 $ 442 $ 3,402 $ 751 $ 416 $ 127 $ 6,784 Impaired loans $ 3,575 $ 623 $ 4,751 $ — $ — $ — $ 8,949 Non-impaired loans 232,073 47,543 139,142 31,050 20,259 10,289 480,356 Total loans $ 235,648 $ 48,166 $ 143,893 $ 31,050 $ 20,259 $ 10,289 $ 489,305 As described in Note 3 – “Global Pandemic Affecting Randolph Bancorp, Inc.” the COVID-19 pandemic has affected the Company’s operations starting in the first quarter of 2020. This pandemic has severely disrupted normal economic activity in the communities the Company serves along with the rest of the nation. It is impossible to know the full extent of the impact of the COVID-19 pandemic and the continued effects it may have on the Company’s operations. Management has determined a separate qualitative element of the allowance to represent the estimate of probable incurred losses associated with the impact of the pandemic events on the Company’s loan portfolios. This estimate is judgmental and subject to changes as conditions evolve. This qualitative element of the allowance was determined based on the impact the pandemic has had on employment levels, economic activity in the Company’s geographic regions, and the time it could take for the affected regions to return to a more normalized operating environment. The following is a summary of past due and non-accrual loans at March 31, 2021 and December 31, 2020: 30 - 59 Days Past Due 60 - 89 Days Past Due 90 Days or More Past Due Total Past Due Non-accrual Loans (In thousands) March 31, 2021 Residential one- to four-family $ 728 $ — $ 668 $ 1,396 $ 2,158 Home equity loans and lines of credit — — — — 383 Commercial real estate — — — — 5,768 Construction — — — — — Commercial and industrial — — — — — Consumer 10 4 — 14 — Total $ 738 $ 4 $ 668 $ 1,410 $ 8,309 December 31, 2020 Residential one-to-four family $ - $ — $ — $ — $ 1,876 Home equity loans and lines of credit 95 — 317 412 584 Commercial real estate — — 26 26 4,713 Construction — — — — — Commercial and industrial — — — — — Consumer 38 64 — 102 — Total $ 133 $ 64 $ 343 $ 540 $ 7,173 The following is a summary of impaired loans at March 31, 2021 and December 31, 2020: Recorded Investment Unpaid Principal Balance Related Allowance (In thousands) March 31, 2021 Impaired loans without a valuation allowance: Residential one- to four-family $ 2,276 $ 2,296 Home equity loans and lines of credit 425 423 Commercial real estate 5,768 5,762 Total 8,469 8,481 Impaired loans with a valuation allowance: Residential one- to four-family 1,536 1,549 $ 132 Commercial real estate 17 17 $ 17 1,553 1,566 149 Total impaired loans $ 10,022 $ 10,047 $ 149 December 31, 2020 Impaired loans without a valuation allowance: Residential one- to four-family $ 2,160 $ 2,181 Home equity loans and lines of credit 626 623 Commercial real estate 4,753 4,751 Total 7,539 7,555 Impaired loans with a valuation allowance: Residential one- to four-family 1,382 1,394 $ 133 Total 1,382 1,394 133 Total impaired loans $ 8,921 $ 8,949 $ 133 Additional information pertaining to impaired loans follows: Average Interest Cash Basis Recorded Income Interest Investment Recognized Recognized (In thousands) Three Months Ended March 31, 2021 Residential one- to four-family $ 3,755 $ 18 $ 39 Home equity loans and lines of credit 424 — — Commercial real estate 5,780 — — Total $ 9,959 $ 18 $ 39 Three Months Ended March 31, 2020 Residential one- to four-family $ 5,336 $ 58 $ 29 Home equity loans and lines of credit 405 1 — Total $ 5,741 $ 59 $ 29 No additional funds are committed to be advanced in connection with impaired loans. Troubled Debt Restructurings The Company periodically grants concessions to borrowers experiencing financial difficulties. The Company’s troubled debt restructurings consist primarily of interest rate concessions for periods of three months to thirty years for residential real estate loans, and for periods up to one year for commercial real estate loans. Number of Contracts TDRs Listed as Accrual Number of Contracts TDRs Listed as Non-accrual Number of Contracts Total TDRs (In thousands) March 31, 2021 Residential one- to four-family 12 $ 1,654 4 $ 1,157 16 $ 2,811 Home equity loans and lines of credit 1 42 - — 1 42 Commercial real estate 1 17 - — 1 17 Total 14 $ 1,713 4 $ 1,157 18 $ 2,870 December 31, 2020 Residential one- to four-family $ 12 $ 1,666 $ 4 $ 1,167 16 $ 2,833 Home equity loans and lines of credit 1 42 - — 1 42 Commercial real estate 1 40 - — 1 40 Total 14 1,748 4 $ 1,167 18 $ 2,915 For the three months ended March 31, 2021 and 2020, respectively, the Company did not enter into any loan modifications meeting the criteria of a troubled debt restructuring. Management performs a discounted cash flow calculation to determine the amount of valuation reserve required on each of the troubled debt restructurings. Any reserve required is recorded as part of the allowance for loan losses. During the three months ended March 31, 2021 and 2020, there were no material changes to the allowance for loan losses as a result of loan modifications made which were considered a troubled debt restructuring. During the three months ended March 31, 2021 and 2020, there were no troubled debt restructurings that defaulted (over 30 days past due) within twelve months of the restructure date. At March 31, 2021 there were two residential real estate troubled debt restructurings that were granted payment deferral plans. One loan, totaling $297,000, was performing in accordance with its modified terms, and one loan, for $196,000 was not performing in accordance with its modified terms and is currently still in payment suspense. Credit Quality Information The Company utilizes an eight-grade internal loan rating system for commercial real estate, construction and commercial and industrial loans, as follows: Loans rated 1 – 3B are considered “pass” rated loans with low to average risk. Loans rated 4 are considered “special mention.” These loans are starting to show signs of potential weakness and are being closely monitored by management. Loans rated 5 are considered “substandard” and are inadequately protected by the current net worth and paying capacity of the obligors and/or the collateral pledged. There is a distinct possibility that the Company will sustain some loss if the weakness is not corrected. Loans rated 6 are considered “doubtful” and have all the weaknesses inherent in those classified substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, highly questionable and improbable. Loans rated 7 are considered uncollectible (“loss”) and of such little value that their continuance as loans is not warranted. On an annual basis, or more often if needed, the Company formally reviews the ratings on all commercial real estate, construction and commercial and industrial loans. Annually, the Company engages an independent third party to review a significant portion of loans within these segments. Management uses the results of these reviews as part of its annual review process. The following table presents the Company’s loans by risk rating at the dates indicated: Residential 1-4 Family Second Mortgages and HELOC Commercial Real Estate Construction Commercial and Industrial Consumer (In thousands) March 31, 2021 Not Rated $ 237,032 $ 48,690 $ — $ — $ — $ 8,724 Loans rated 1 - 3B (Pass rated) — — 133,014 29,975 23,459 — Loans rated 4 1,094 383 8,154 — 410 — Loans rated 5 1,064 — 5,762 — — — $ 239,190 $ 49,073 $ 146,930 $ 29,975 $ 23,869 $ 8,724 December 31, 2020 Not Rated $ 233,773 $ 47,582 $ — $ — $ — $ 10,289 Loans rated 1 - 3B (Pass rated) — — 129,925 31,050 19,828 — Loans rated 4 803 584 9,257 — 431 — Loans rated 5 1,072 — 4,711 — — — $ 235,648 $ 48,166 $ 143,893 $ 31,050 $ 20,259 $ 10,289

Loan Servicing

Loan Servicing	3 Months Ended
	Mar. 31, 2021
Transfers And Servicing [Abstract]
Loan Servicing	7 . LOAN SERVICING Mortgage loans serviced for others are not included in the accompanying unaudited consolidated balance sheets. The unpaid principal balances of residential mortgage loans serviced for others were $1.94 billion and $1.76 billion at March 31, 2021 and December 31, 2020, respectively. In connection with these serviced loans, we maintained $17.0 million and $14.2 million of custodial escrow balances at March 31, 2021 and December 31, 2020, respectively. The following table summarizes the activity relating to mortgage servicing rights (“MSRs”) for the three months ended March 31, 2021 and 2020 (in thousands): March 31, 2021 March 31, 2020 Mortgage servicing rights: Balance at beginning of year $ 15,372 $ 9,484 Additions through originations 2,786 877 Amortization (840 ) (383 ) Balance at end of period $ 17,318 $ 9,978 Valuation allowance: Balance at beginning of year $ 2,995 $ 928 Provision (recovery) (421 ) 1,562 Balance at end of period $ 2,574 $ 2,490 Amortized cost, net $ 14,744 $ 7,488 Fair value $ 15,362 $ 7,515 During the three months ended March 31, 2021 the Company decreased the valuation allowance for its MSRs by $421,000. During the three months ended March 31, 2020, the Company increased the valuation allowance for its MSRs by $1,562,000. Such adjustments to the valuation allowance were due primarily to changes in fair value caused by the impact of changes in interest rates on expected loan prepayments.

On-Balance Sheet Derivative Ins

On-Balance Sheet Derivative Instruments and Hedging Activities	3 Months Ended
	Mar. 31, 2021
Derivative Instruments And Hedging Activities Disclosure [Abstract]
On-Balance Sheet Derivative Instruments and Hedging Activities	8 . ON-BALANCE SHEET DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES Derivative Loan Commitments Mortgage loan interest rate lock commitments qualify as derivative loan commitments if the loan that will result from exercise of the commitment will be held for sale upon funding. The Company enters into commitments to fund residential mortgage loans at specified rates and times in the future, with the intention that these loans will subsequently be sold either in the secondary market, to large aggregators of loans or to other financial institutions. Outstanding derivative loan commitments expose the Company to the risk that the price of the loans arising from exercise of the loan commitment might decline from inception of the rate lock to funding of the loan due to an increase in mortgage interest rates. If interest rates increase, the value of these loan commitments decreases. Conversely, if interest rates decrease, the value of these loan commitments increases. The notional amount of derivative loan commitments was $239,509,000 and $396,551,000 at March 31, 2021 and December 31, 2020, respectively. The fair value of such commitments at March 31, 2021 and December 31, 2020 was $2,202,000 and $11,821,000, respectively, and is included in other assets in the consolidated balance sheets. Forward Loan Sale Commitments The Company utilizes both “mandatory delivery” and “best efforts” forward loan sale commitments and To Be Announced (“TBA”) securities to mitigate the risk of potential decreases in the value of loans that would result from the exercise of the derivative loan commitments as well as for loans held for sale. With a “mandatory delivery” contract, the Company commits to deliver a certain principal amount of mortgage loans to an investor at a specified price on or before a specified date. If the Company fails to deliver the amount of mortgages necessary to fulfill the commitment by the specified date, it is obligated to pay a “pair-off” fee, based on then-current market prices, to the investor to compensate the investor for the shortfall. With a “best efforts” contract, the Company commits to deliver an individual mortgage loan of a specified principal amount and quality to an investor if the loan to the underlying borrower closes. Generally, the price the investor will pay the seller for an individual loan is specified prior to the loan being funded (e.g., on the same day the lender commits to lend funds to a potential borrower). The Company expects that these forward loan sale commitments and TBA securities will experience changes in fair value that serve to offset the change in fair value of loans held for sale and derivative loan commitments, the degree to which depends on the notional amount of such sale commitments. The notional amount of forward loan sale commitments and TBA securities was $237,778,000 and $390,248,000 at March 31, 2021 and December 31, 2020, respectively. The fair value of such commitments consisted of liabilities of $0 and $2,180,000 at March 31, 2021 and December 31, 2020, respectively, included in other liabilities in the consolidated balance sheets and assets of $3,619,000 and $44,000 at March 31, 2021 and December 31, 2020, respectively, and are included in other assets in the consolidated balance sheets.

Employee Stock Ownership Plan

Employee Stock Ownership Plan	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Employee Stock Ownership Plan	9 . EMPLOYEE STOCK OWNERSHIP PLAN The Company maintains an Employee Stock Ownership Plan (“ESOP”), which is a tax-qualified retirement plan providing eligible employees the opportunity to own Bancorp stock. Bancorp made a loan to the ESOP for the purchase of 469,498 shares of its common stock at $10.00 per share in connection with its initial public offering in July 2016. The loan is payable annually over 25 years with interest at the prime rate to be reset each January 1. The loan is secured by the shares which have not yet been allocated to participants. Loan payments are funded by cash contributions from the Bank. Such contributions are allocated to eligible participants based on their compensation, subject to federal tax limits. Shares are committed to be released on a monthly basis and allocated as of December 31 of each year. The number of shares to be allocated annually is 18,780 through the year 2040. For the three months ended March 31, 2021 and 2020, the Company recognized compensation expense for the ESOP of $94,000 and $68,000, respectively. The fair value of the 370,967 unallocated ESOP shares at March 31, 2021 was $7,419,000.

Share Repurchase Program

Share Repurchase Program	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Share Repurchase Program	1 0 . SHARE REPURCHASE PROGRAM In October 2020, the Company’s Board of Directors adopted a share repurchase program under which the Company may repurchase up to 10%, or 552,000 shares, of its then outstanding common shares. Repurchases under the program may be made in open market or in privately negotiated transactions and pursuant to any trading plan that may be adopted in accordance with Rule 10b5-1 of the SEC. Any repurchased shares will be held by the Company as authorized but unissued shares. The repurchase program may be suspended or terminated at any time without prior notice and is currently set to expire on October 29, 2021. As of March 31, 2021, the Company had repurchased 159,640 shares at a cost of $3,156,000 in connection with this program.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	1 1 . EARNINGS (LOSS) PER SHARE Basic earnings (loss) per share represents net income (loss) divided by the weighted average of common shares outstanding during the period. Unvested restricted shares of common stock having dividend rights are treated as “participating securities” and, accordingly, are considered outstanding in computing basic earnings (loss) per share. Unallocated ESOP shares are not considered to be outstanding for purposes of computing earnings per share. The following table sets forth the calculation of the average number of shares outstanding used to calculate the basic and diluted earnings (loss) per share for the periods indicated: Three Months Ended March 31, 2021 2020 Average number of common shares outstanding 5,429,422 5,550,324 Less: Average unallocated ESOP shares (373,257 ) (392,030 ) Average number of common shares outstanding used to calculate basic earnings per share 5,056,165 5,158,294 Effect of dilutive stock options 198,742 — Average number of common shares outstanding used to calculate dilutive earnings per share 5,254,907 5,158,294

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	1 2 . STOCK-BASED COMPENSATION Under the Randolph Bancorp, Inc. 2017 Stock Option and Incentive Plan (the “Equity Plan”), the Company may grant options, restricted stock, restricted units or performance awards to its directors, officers and employees. Both incentive stock options and nonqualified stock options may be granted under the Equity Plan with 586,872 shares initially reserved for options. Any options forfeited because vesting requirements are not met or expired will become available for re-issuance under the Equity Plan. The exercise price of each option equals the market price of the Company’s stock on the date of the grant and the maximum term of each option is 10 years. The total number of shares initially reserved for restricted stock is 234,749. Options and awards generally vest ratably over three to five years. The fair value of shares awarded is based on the market price at the date of grant. In addition, the Company granted 15,000 shares of restricted stock and 44,118 options in 2020 as an inducement for senior executives to accept employment (the “2020 Inducement Plan”). The inducement awards and options vest ratably over five years. The fair value of shares awarded is based on the market price at the date of grant. Stock Options The fair value of each option grant is estimated on the date of the grant using the Black-Scholes option-pricing model with the following assumptions: • Volatility is based on peer group volatility because the Company does not have a sufficient trading history. • Expected life represents the period of time that the option is expected to be outstanding, taking into account the contractual term, and the vesting period. • Expected dividend yield is based on the Company's history and expectation of dividend payouts. • The risk-free rate is based on the U.S. Treasury yield curve in effect at the time of grant for a period equivalent to the expected life of the option. During the three months ended March 31, 2021 and 2020, the Company made the following grants of options to purchase shares of common stock and used the following assumptions in measuring the fair value of such grants: 2021 2020 Options granted 40,491 79,000 Vesting period (years) 5 5 Expiration period (years) 10 10 Expected volatility 30.98 % 24.94 % Expected life (years) 6.2 6.0 Expected dividend yield — — Risk free interest rate 0.64 % 1.47 % Option fair value $ 6.20 $ 5.74 A summary of stock option activity for the three months ended March 31, 2021 is presented in the table below: Options Stock Option Grants Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Balance at January 1, 2021 587,168 $ 13.32 8.40 $ — Granted 40,491 20.06 Balance at March 31, 2021 627,659 $ 13.75 8.27 $ 3,923,110 Exercisable at March 31, 2021 177,788 $ 15.01 7.07 $ 887,395 Unrecognized compensation cost (inclusive of directors' options) $ 1,565,435 Weighted average remaining recognition period (years) 2.85 For the three months ended March 31, 2021 and 2020 stock-based compensation expense applicable to stock options was $142,000 and $309,000, respectively. Included in expense for the period ended March 31, 2020 is $233,000 attributable to accelerated vesting of options upon the retirement of two executive officers. Restricted Stock Shares issued may be either authorized but unissued shares or reacquired shares held by the Company. Any shares forfeited because vesting requirements are not met will become available for reissuance under the Equity Plan. The fair market value of shares awarded, based on the market price at the date of grant, is amortized over the applicable vesting period. Restricted stock awarded to date has been at no cost to the awardee. The following table presents the activity in restricted stock awards under the Equity Plan for the three months ended March 31, 2021: Restricted Stock Awards Weighted Average Grant Price Restricted stock awards at January 1, 2021 122,012 $ 12.72 Granted — — Vested (2,500 ) 15.00 Forfeited — — Restricted stock awards at March 31, 2021 119,512 $ 12.67 Unrecognized compensation cost $ 1,219,423 Weighted average remaining recognition period (years) 3.18 For the three months ended March 31, 2021 and 2020 stock-based compensation expense applicable to restricted stock was $125,000 and $622,000, respectively. Included in expense for the period ended March 31, 2020 is $450,000 attributable to accelerated vesting of restricted stock awards upon the retirement of two executive officers.

Fair Value of Assets and Liabil

Fair Value of Assets and Liabilities	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value of Assets and Liabilities	1 3 . FAIR VALUE OF ASSETS AND LIABILITIES Determination of fair value The Company uses fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value is best determined based upon quoted market prices. However, in many instances, there are no quoted market prices for the Company’s various assets and liabilities. In cases where quoted market prices are not available, fair values are based on estimates using present value or other valuation techniques. Those techniques are significantly affected by the assumptions used, including the discount rate and estimates of future cash flows. Accordingly, the fair value estimates may not be realized in an immediate settlement of the asset or liability. The following methods and assumptions were used by the Company in estimating fair value disclosures: Securities Loans held for sale Loans Mortgage servicing rights On-balance-sheet derivatives Off-balance sheet credit-related instruments Assets and liabilities recorded at fair value on a recurring basis Assets and liabilities recorded at fair value on a recurring basis are summarized below. Total Level 1 Level 2 Level 3 Fair (In thousands) March 31, 2021 Assets: Securities available for sale $ — $ 54,148 $ — $ 54,148 Portfolio loans (fair value option) — 17,215 — 17,215 Loans held for sale (fair value option) — 93,176 — 93,176 Derivative loan commitments — 2,202 — 2,202 Forward loan sale commitments, including TBAs — 3,619 — 3,619 Liabilities: Forward loan sale commitments, including TBAs — — — — December 31, 2020 Assets: Securities available for sale $ — $ 55,366 $ — $ 55,366 Portfolio loans (fair value option) — 13,780 — 13,780 Loans held for sale (fair value option) — 119,112 — 119,112 Derivative loan commitments — 11,821 — 11,821 Forward loan sale commitments — 44 — 44 Liabilities: Forward loan sale commitments, including TBAs — 2,180 — 2,180 There were no transfers between levels for assets and liabilities recorded at fair value on a recurring basis during the three months ended March 31, 2021 and 2020. Assets recorded at fair value on a non-recurring basis The Company may also be required, from time to time, to record certain other assets at fair value on a non-recurring basis in accordance with GAAP. These adjustments to fair value usually result from application of lower-of-cost-or-market accounting or write-downs of individual assets. The following table summarizes the fair value hierarchy used to determine each adjustment and the carrying value of the related assets as of March 31, 2021 and December 31, 2020. Period Ended March 31, 2021 March 31, 2021 Level 1 Level 2 Level 3 Total Gains (Losses) (In thousands) Collateral dependent impaired loans $ — $ — $ 7,462 $ — Mortgage servicing rights — 14,744 — 421 Foreclosed real estate — — 132 — $ — $ 14,744 $ 7,594 $ 421 December 31, 2020 Level 1 Level 2 Level 3 (In thousands) Collateral dependent impaired loans $ — $ — $ 6,318 Mortgage servicing rights — 12,377 — Foreclosed real estate — — 132 $ — $ 12,377 $ 6,450 The Company recorded a decrease in the valuation allowance for its MSRs of $421,000 during the three months ended March 31, 2021. The Company utilizes an independent valuation from a third party which uses a discounted cash flow model to estimate the fair value of MSRs. The model uses loan prepayment assumptions based on current market conditions and applies a discount rate based on indicated rates of return required by market participants. The decrease in the valuation allowance during the three months ended March 31, 2021 was caused by slower loan prepayment speeds attributable to the increase in interest rates on residential mortgage loans during the period. L osses applicable to write-downs of impaired loans and foreclosed real estate are based on the appraised value of the underlying collateral less estimated costs to sell. The losses on impaired loans are not recorded directly as an adjustment to current earnings, but rather as a component in determining the allowance for loan losses. The losses on foreclosed real estate represent adjustments in valuation recorded during the time period indicated and not for losses incurred on sales. Appraised values are typically based on a blend of (a) an income approach using observable cash flows to measure fair value, and (b) a market approach using observable market comparisons. These appraised values may be discounted based on management’s historical knowledge, expertise or changes in market conditions from time of valuation. There were no liabilities measured at fair value on a non-recurring basis at March 31, 2021 and December 31, 2020. Summary of fair values of financial instruments The estimated fair values, and related carrying amounts, of the Company’s financial instruments are presented below. Certain financial instruments and all non-financial instruments are exempt from disclosure requirements. Accordingly, the aggregate fair value amounts presented herein do not represent the underlying fair value of the Company. This table excludes financial instruments for which the carrying amount approximates fair value. Financial assets for which the fair value approximates carrying value include cash and cash equivalents, and accrued interest receivable. Financial liabilities for which the fair value approximates carrying value include mortgagors’ escrow accounts and accrued interest payable. March 31, 2021 Carrying Fair Amount Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Securities available for sale 54,148 54,148 — 54,148 — Loans held for sale 93,176 93,176 — 93,176 — Loans, net 491,983 498,850 — — 498,850 Derivative assets 5,821 5,821 — 5,821 — Financial liabilities: Deposits $ 560,258 $ 560,498 $ — $ 560,498 $ — FHLBB advances 60,024 60,702 — 60,702 — Derivative liabilities — — — — — December 31, 2020 Carrying Fair Amount Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Securities available for sale 55,366 55,366 — 55,366 — Loans held for sale 119,112 119,112 — 119,112 — Loans, net 483,644 490,914 — — 490,914 Derivative assets 11,865 11,865 — 11,865 — Financial liabilities: Deposits $ 528,307 528,786 $ — $ 528,786 $ — FRB advances 11,431 11,431 — 11,431 — FHLBB advances 61,895 63,071 63,071 Derivative liabilities 2,180 2,180 — 2,180 —

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	1 4 . COMMITMENTS AND CONTINGENCIES Loan commitments The Company is a party to financial instruments with off-balance-sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit. These instruments involve, to varying degrees, elements of market, credit and interest rate risk which are not recognized in the unaudited consolidated financial statements. The Company’s exposure to credit loss is represented by the contractual amount of these commitments. The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance-sheet instruments. The following financial instruments were outstanding, at the dates indicated, whose contract amounts represent credit risk: March 31, 2021 December 31, 2020 (In thousands) Commitments to originate loans $ 251,697 $ 411,401 Unused lines and letters of credit 75,681 71,458 Unadvanced funds on construction loans 12,343 9,110 Overdraft lines of credit 7,910 7,969 Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. The commitments for lines of credit may expire without being drawn upon. Therefore, the total commitment amounts do not necessarily represent future cash requirements. The Company evaluates each customer’s creditworthiness on a case-by-case basis. The majority of these financial instruments are collateralized by real estate. Other contingencies The Company is not currently a party to any pending legal proceedings that it believes would have a material adverse effect on its financial condition, results of operations or cash flows.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Segment Information	1 6 . SEGMENT INFORMATION The Company reports its activities in one of two business segments, namely Envision Bank (“EB”) and Envision Mortgage (“EM”). Envision Bank operations primarily consist of accepting deposits from customers within the communities surrounding the Bank’s five full-service branch offices and investing those funds in residential and commercial real estate loans, home equity lines of credit, construction loans, commercial and industrial loans, and consumer loans. Envision Mortgage’s operations primarily consist of the origination and sale of residential mortgage loans and the servicing of loans sold to government-sponsored entities. A portion of the loans originated by Envision Mortgage are held in the loan portfolio of Envision Bank. Segment information as of and for the three months ended March 31, 2021 follows: For the Three Months Ended March 31, 2021 Envision Bank Envision Mortgage Consolidated Total (in thousands) Net interest income $ 4,201 $ 890 $ 5,091 Provision (credit) for loan losses (213 ) — (213 ) Net interest income after provision (credit) for loan losses 4,414 890 5,304 Non-interest income: Customer service fees 340 27 367 Gain on loan origination and sale activities, net (1) — 11,674 11,674 Mortgage servicing fees, net (94 ) 873 779 Other 151 133 284 Total non-interest income 397 12,707 13,104 Non-interest expenses: Salaries and employee benefits 1,802 6,635 8,437 Occupancy and equipment 443 301 744 Other non-interest expenses 1,087 1,683 2,770 Total non-interest expenses 3,332 8,619 11,951 Income before income taxes and elimination of inter-segment profit $ 1,479 $ 4,978 6,457 Elimination of inter-segment profit (681 ) Income before income taxes 5,776 Income tax expense 1,664 Net income $ 4,112 Total assets, March 31, 2021 $ 581,954 $ 156,234 $ 738,188 (1) Before elimination of inter-segment profit. The information above was derived from the internal management reporting system used by management to measure performance of the segments. The Company’s internal transfer pricing arrangements determined by management primarily consist of the following: 1. EM’s cost of funds is based on the weighted average rate of overnight advances from the FHLBB for the period. 2. EM is credited with service released premiums and a sales premium totaling 1.50% for new loans transferred to EB’s loans held for investment, and a 1.00% fee for home equity line of credit (“HELOC”) originations. This income for the three months ended March 31, 2021 totaled $681,000. 3. Loan servicing fees are charged to EB by EM based on the number of residential mortgage loans held in portfolio at a rate of 0.14% per annum and amounted to $94,000 for the three months ended March 31, 2021 4. Certain cost centers provide services to both business segments. The cost centers include Finance, Marketing, IT and Administration. Costs which are common to both business segments are referred to as “indirect costs” and are allocated using relevant benchmarks, e.g. headcount, number of accounts, etc. Segment information as of and for the three and three months ended March 31, 2020 follows: For the Three Months Ended March 31, 2020 Envision Bank Envision Mortgage Consolidated Total (in thousands) Net interest income $ 3,994 $ 431 $ 4,425 Provision for loan losses 724 — 724 Net interest income after provision for loan losses 3,270 431 3,701 Non-interest income: Customer service fees 273 33 306 Gain on loan origination and sale activities, net (1) — 7,472 7,472 Mortgage servicing fees, net (87 ) (1,167 ) (1,254 ) Other 140 115 255 Total non-interest income 326 6,453 6,779 Non-interest expenses: Salaries and employee benefits 3,098 5,028 8,126 Occupancy and equipment 404 294 698 Other non-interest expenses 1,146 989 2,135 Total non-interest expenses 4,648 6,311 10,959 Income (loss) before income taxes and elimination of inter-segment profit $ (1,052 ) $ 573 (479 ) Elimination of inter-segment profit (328 ) Loss before income taxes (807 ) Income tax benefit 11 Net loss $ (818 ) Total assets, March 31, 2020 $ 543,586 $ 109,300 $ 652,886 (1) Before elimination of inter-segment profit. (2) Salaries and benefits include the severance and vested stock acceleration costs related to the retirement of the Chief Executive Officer and Chief Financial Officer of the Bank. The cost of this event was $1.38 million, of which $1.03 million was allocated to the Bank segment and the remainder, $344,000, was allocated to the mortgage segment. The information above was derived from the internal management reporting system used by management to measure performance of the segments. The Company’s internal transfer pricing arrangements determined by management primarily consist of the following: 1. EM’s cost of funds is based on the weighted average rate of overnight advances from the FHLBB for the period. 2. EM is credited with service released premiums and a sales premium totaling 1.50% for new loans transferred to EB’s loans held for investment, and a 1.00% fee for HELOC originations. This income for the three months ended March 31, 2020 totaled $328,000. 3. Loan servicing fees are charged to EB by EM based on the number of residential mortgage loans held in portfolio at a rate of 0.14% per annum and amounted to $87,000 for the three months ended March 31, 2020. 4. Certain cost centers provide services to both business segments. The cost centers include Finance, Marketing, IT and Administration. Costs which are common to both business segments are referred to as “indirect costs” and are allocated using relevant benchmarks, e.g. headcount, number of accounts, etc.

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Recent Accounting Pronouncements	In February 2016, FASB issued ASU 2016-02, Leases In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses

Global Pandemic Affecting Ran_2

Global Pandemic Affecting Randolph Bancorp, Inc. (Tables)	3 Months Ended
	Mar. 31, 2021
Risks And Uncertainties [Abstract]
Summary of Lending Activity and Outstanding Balances of PPP Loans and The Associated Pledges	The table below summarizes the lending activity and outstanding balances of PPP loans and the associated pledges to the Federal Reserve Bank’s (“FRB”) Paycheck Protection Program Liquidity Facility (“PPPLF”): PPP Loan Balance FRB Advances PPP Loans Outstanding at Amount Pledged Outstanding at Originated March 31, 2021 to PPPLF March 31, 2021 (1) (In thousands) 2020 PPP loans $ 15,387 $ 4,557 $ 15,387 $ - 2021 PPP loans 10,160 10,160 - - Total Activity $ 25,547 $ 14,717 $ 15,387 $ - (1) FRB advances were fully repaid during the first quarter of 2021 and the associated PPP loans are no longer pledged.
Summary of Loan Portfolio	The table below summarizes the status of the bank’s loan deferral activity: Status of Deferrals Granted Currently Outstanding Paid Off Deferrals Suspended/ Resumed Full Granted (1) Reduced Payment (2) Payment (2) Payoff (3) (In thousands) March 31, 2021 Real estate loans: Residential: One- to four-family $ 16,793 $ 4,316 $ 9,107 $ 3,370 Home equity loans and lines of credit 3,168 423 1,479 1,266 Construction 350 - 350 - Commercial 34,616 6,241 24,628 3,747 Total real estate loans 54,927 10,980 35,564 8,383 Commercial and industrial 3,579 - 1,569 2,010 Consumer 68 38 30 - Total $ 58,574 $ 11,018 $ 37,163 $ 10,393 December 31, 2020 Real estate loans: Residential: One- to four-family $ 15,514 $ 12,974 $ 2,109 $ 431 Home equity loans and lines of credit 3,179 626 1,287 1,266 Construction 350 350 - - Commercial 34,754 6,544 25,406 2,804 Total real estate loans 53,797 20,494 28,802 4,501 Commercial and industrial 3,645 - 1,635 2,010 Consumer 68 68 - - Total $ 57,510 $ 20,562 $ 30,437 $ 6,511 (1) This column equals the current outstanding balance of loans that received a deferral, plus the balance of loans that were deferred and were paid off in full. (2) These two columns are the current balance of all loans that received a deferral. The Suspended/Reduced Payment columns represents loans currently in a deferral period and the Resumed Payment columns represents loans that are no longer in a deferral period and have resumed normal payment. (3) This column represents the balance of deferred loans that were paid off in full. A summary of the loan portfolio is as follows: March 31, 2021 December 31, 2020 (In thousands) Real estate loans: Residential: One- to four-family $ 239,190 $ 235,648 Home equity loans and lines of credit 49,073 48,166 Commercial 146,930 143,893 Construction 29,975 31,050 465,168 458,757 Commercial and industrial 23,869 20,259 Consumer 8,724 10,289 Total loans 497,761 489,305 Allowance for loan losses (6,563 ) (6,784 ) Net deferred loan costs and fees, and purchase premiums 785 1,123 $ 491,983 $ 483,644
Schedule of Past Due and Non-Accrual Loans by Loan Category	Accordingly, the table below summarizes the risk rating and for all loans that were granted deferral and are outstanding, and any loans that were listed in nonaccrual status at the dates indicated: Currently Outstanding Deferred Loans by Risk Rating Pass Rated / Special Sub- Non- Not Rated (1) Mention (1) standard (1) accrual (2) (In thousands) March 31, 2021 Real estate loans: Residential: One- to four-family $ 13,228 $ 195 $ - $ 195 Home equity loans and lines of credit 1,902 - - - Construction 350 - - - Commercial 17,985 7,649 5,235 5,235 Total real estate loans 33,465 7,844 5,235 5,430 Commercial and industrial 1,159 410 - - Consumer 68 - - - Total $ 34,692 $ 8,254 $ 5,235 $ 5,430 December 31, 2020 Real estate loans: Residential: One- to four-family $ 14,887 $ 196 $ - $ 196 Home equity loans and lines of credit 1,913 - - - Construction 350 - - - Commercial 19,020 8,748 4,182 4,182 Total real estate loans 36,170 8,944 4,182 4,378 Commercial and industrial 1,204 431 - - Consumer 68 - - - Total $ 37,442 $ 9,375 $ 4,182 $ 4,378 (1) These three columns indicate the risk rating and subsequent outstanding balance of loans that have received a deferral. The Pass Rated/Not Rated, Special Mention and Substandard columns reconcile to the Suspended Payment/Reduced Payment and Resumed Payment columns in the preceding table. (2) Nonaccrual loans are risk rated as either special mention or substandard loans and are included as a balance in those columns. The following is a summary of past due and non-accrual loans at March 31, 2021 and December 31, 2020: 30 - 59 Days Past Due 60 - 89 Days Past Due 90 Days or More Past Due Total Past Due Non-accrual Loans (In thousands) March 31, 2021 Residential one- to four-family $ 728 $ — $ 668 $ 1,396 $ 2,158 Home equity loans and lines of credit — — — — 383 Commercial real estate — — — — 5,768 Construction — — — — — Commercial and industrial — — — — — Consumer 10 4 — 14 — Total $ 738 $ 4 $ 668 $ 1,410 $ 8,309 December 31, 2020 Residential one-to-four family $ - $ — $ — $ — $ 1,876 Home equity loans and lines of credit 95 — 317 412 584 Commercial real estate — — 26 26 4,713 Construction — — — — — Commercial and industrial — — — — — Consumer 38 64 — 102 — Total $ 133 $ 64 $ 343 $ 540 $ 7,173

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Components of Accumulated Other Comprehensive Income (Loss) and Related Tax Effects	The components of accumulated other comprehensive income (loss), included in total stockholders’ equity, are as follows: March 31, December 31, 2021 2020 (In thousands) Securities available for sale: Net unrealized gain $ 795 $ 1,713 Tax effect (193 ) (313 ) Net-of-tax amount 602 1,400 Supplemental retirement plan Unrecognized net actuarial loss (700 ) (712 ) Unrecognized net prior service credit 246 254 (454 ) (458 ) Tax effect (47 ) (47 ) Net-of-tax amount (501 ) (505 ) Accumulated other comprehensive income (loss) $ 101 $ 895

Securities Available for Sale (

Securities Available for Sale (Tables)	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Schedule of Amortized Cost and Fair Value of Securities	The amortized cost and fair value of securities available for sale, including gross unrealized gains and losses, are as follows: Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value (In thousands) March 31, 2021 Debt securities: U.S. Treasury $ 3,913 $ — $ (90 ) $ 3,823 U.S. Government-sponsored enterprises 1,993 — (2 ) 1,991 Corporate 4,286 15 (5 ) 4,296 Municipal 595 3 — 598 Residential mortgage-backed securities: U.S. Government-sponsored enterprises 29,023 623 (220 ) 29,426 Commercial mortgage-backed securities: U.S. Government-sponsored enterprises 8,825 361 — 9,186 U.S. Government-guaranteed 559 9 — 568 Collateralized mortgage obligations: U.S. Government-sponsored enterprises 944 41 — 985 U.S. Government-guaranteed 3,215 60 — 3,275 Total securities available for sale $ 53,353 $ 1,112 $ (317 ) $ 54,148 December 31, 2020 Debt securities: U.S. Government-sponsored enterprises $ 1,993 $ 3 $ — $ 1,996 Corporate 4,300 56 — 4,356 Municipal 595 5 — 600 Residential mortgage-backed securities: U.S. Government-sponsored enterprises 32,538 919 — 33,457 Commercial mortgage-backed securities: U.S. Government-sponsored enterprises 8,857 525 — 9,382 U.S. Government-guaranteed 977 24 — 1,001 Collateralized mortgage obligations: U.S. Government-sponsored enterprises 996 52 — 1,048 U.S. Government-guaranteed 3,398 128 — 3,526 Total securities available for sale $ 53,654 $ 1,712 $ — $ 55,366
Investments Classified by Contractual Maturity Date	The amortized cost and fair value of debt securities by contractual maturity at March 31, 2021 are presented below. Expected maturities will differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Amortized Fair Cost Value (In thousands) Within 1 year $ 1,001 $ 1,011 After 1 year through 5 years 4,804 4,811 After 5 years through 10 years 4,982 4,886 10,787 10,708 Mortgage-backed securities 42,566 43,440 $ 53,353 $ 54,148
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	Information pertaining to securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous loss position, follows: Less Over Twelve Months Gross Gross Unrealized Fair Unrealized Fair Losses Value Losses Value March 31, 2021 (In thousands) Debt securities: U.S. Treasury $ (90 ) $ 3,823 $ — $ — U.S. Government-sponsored enterprises (2 ) 1,992 — — Corporate (5 ) 1,801 — — Residential mortgage-backed securities U.S. Government-sponsored enterprises (220 ) 10,356 — — Total debt securities $ (317 ) $ 17,972 $ — $ —

Loans and Allowance for Loan _2

Loans and Allowance for Loan Losses (Tables)	3 Months Ended
	Mar. 31, 2021
Receivables [Abstract]
Summary of Loan Portfolio	The table below summarizes the status of the bank’s loan deferral activity: Status of Deferrals Granted Currently Outstanding Paid Off Deferrals Suspended/ Resumed Full Granted (1) Reduced Payment (2) Payment (2) Payoff (3) (In thousands) March 31, 2021 Real estate loans: Residential: One- to four-family $ 16,793 $ 4,316 $ 9,107 $ 3,370 Home equity loans and lines of credit 3,168 423 1,479 1,266 Construction 350 - 350 - Commercial 34,616 6,241 24,628 3,747 Total real estate loans 54,927 10,980 35,564 8,383 Commercial and industrial 3,579 - 1,569 2,010 Consumer 68 38 30 - Total $ 58,574 $ 11,018 $ 37,163 $ 10,393 December 31, 2020 Real estate loans: Residential: One- to four-family $ 15,514 $ 12,974 $ 2,109 $ 431 Home equity loans and lines of credit 3,179 626 1,287 1,266 Construction 350 350 - - Commercial 34,754 6,544 25,406 2,804 Total real estate loans 53,797 20,494 28,802 4,501 Commercial and industrial 3,645 - 1,635 2,010 Consumer 68 68 - - Total $ 57,510 $ 20,562 $ 30,437 $ 6,511 (1) This column equals the current outstanding balance of loans that received a deferral, plus the balance of loans that were deferred and were paid off in full. (2) These two columns are the current balance of all loans that received a deferral. The Suspended/Reduced Payment columns represents loans currently in a deferral period and the Resumed Payment columns represents loans that are no longer in a deferral period and have resumed normal payment. (3) This column represents the balance of deferred loans that were paid off in full. A summary of the loan portfolio is as follows: March 31, 2021 December 31, 2020 (In thousands) Real estate loans: Residential: One- to four-family $ 239,190 $ 235,648 Home equity loans and lines of credit 49,073 48,166 Commercial 146,930 143,893 Construction 29,975 31,050 465,168 458,757 Commercial and industrial 23,869 20,259 Consumer 8,724 10,289 Total loans 497,761 489,305 Allowance for loan losses (6,563 ) (6,784 ) Net deferred loan costs and fees, and purchase premiums 785 1,123 $ 491,983 $ 483,644
Summary of Activity in the Allowance for Loan Losses by Loan Category	The following tables present activity in the allowance for loan losses by loan category for the three months ended March 31, 2021 and 2020, and allocation of the allowance to each category as of March 31, 2021 and December 31, 2020: Residential 1-4 Family Second Mortgages and HELOC Commercial Real Estate Construction Commercial and Industrial Consumer Total (In thousands) Three Months Ended March 31, 2021 Allowance at December 31, 2020 $ 1,646 $ 442 $ 3,402 $ 751 $ 416 $ 127 $ 6,784 Provision (credit) for loan losses (126 ) (17 ) (12 ) (31 ) (15 ) (12 ) (213 ) Loans charged-off — — — — — (10 ) (10 ) Recoveries 2 — — — — — 2 Balance at March 31, 2021 $ 1,522 $ 425 $ 3,390 $ 720 $ 401 $ 105 $ 6,563 Three Months Ended March 31, 2020 Allowance at December 31, 2019 $ 1,096 $ 289 $ 1,840 $ 692 $ 235 $ 128 $ 4,280 Provision for loan losses 123 54 401 80 45 21 724 Loans charged-off — — — — — (16 ) (16 ) Recoveries 4 — — — — 4 8 Balance at March 31, 2020 $ 1,223 $ 343 $ 2,241 $ 772 $ 280 $ 137 $ 4,996
Summary of Additional Information Pertaining to the Allowance for Loan Losses	Additional information pertaining to the allowance for loan losses at March 31, 2021 and December 31, 2020 is as follows: Residential 1-4 Family Second Mortgages and HELOC Commercial Real Estate Construction Commercial and Industrial Consumer Total March 31, 2021 (In thousands) Allowance for impaired loans $ 132 $ — $ 17 $ — $ — $ — $ 149 Allowance for non-impaired loans 1,390 425 3,373 720 401 105 6,414 Total allowance for loan losses $ 1,522 $ 425 $ 3,390 $ 720 $ 401 $ 105 $ 6,563 Impaired loans $ 3,845 $ 423 $ 5,779 $ — $ — $ — $ 10,047 Non-impaired loans 235,345 48,650 141,151 29,975 23,869 8,724 487,714 Total loans $ 239,190 $ 49,073 $ 146,930 $ 29,975 $ 23,869 $ 8,724 $ 497,761 December 31, 2020 Allowance for impaired loans $ 133 $ — $ — $ — $ — $ — $ 133 Allowance for non-impaired loans 1,513 442 3,402 751 416 127 6,651 Total allowance for loan losses $ 1,646 $ 442 $ 3,402 $ 751 $ 416 $ 127 $ 6,784 Impaired loans $ 3,575 $ 623 $ 4,751 $ — $ — $ — $ 8,949 Non-impaired loans 232,073 47,543 139,142 31,050 20,259 10,289 480,356 Total loans $ 235,648 $ 48,166 $ 143,893 $ 31,050 $ 20,259 $ 10,289 $ 489,305
Schedule of Past Due and Non-Accrual Loans by Loan Category	Accordingly, the table below summarizes the risk rating and for all loans that were granted deferral and are outstanding, and any loans that were listed in nonaccrual status at the dates indicated: Currently Outstanding Deferred Loans by Risk Rating Pass Rated / Special Sub- Non- Not Rated (1) Mention (1) standard (1) accrual (2) (In thousands) March 31, 2021 Real estate loans: Residential: One- to four-family $ 13,228 $ 195 $ - $ 195 Home equity loans and lines of credit 1,902 - - - Construction 350 - - - Commercial 17,985 7,649 5,235 5,235 Total real estate loans 33,465 7,844 5,235 5,430 Commercial and industrial 1,159 410 - - Consumer 68 - - - Total $ 34,692 $ 8,254 $ 5,235 $ 5,430 December 31, 2020 Real estate loans: Residential: One- to four-family $ 14,887 $ 196 $ - $ 196 Home equity loans and lines of credit 1,913 - - - Construction 350 - - - Commercial 19,020 8,748 4,182 4,182 Total real estate loans 36,170 8,944 4,182 4,378 Commercial and industrial 1,204 431 - - Consumer 68 - - - Total $ 37,442 $ 9,375 $ 4,182 $ 4,378 (1) These three columns indicate the risk rating and subsequent outstanding balance of loans that have received a deferral. The Pass Rated/Not Rated, Special Mention and Substandard columns reconcile to the Suspended Payment/Reduced Payment and Resumed Payment columns in the preceding table. (2) Nonaccrual loans are risk rated as either special mention or substandard loans and are included as a balance in those columns. The following is a summary of past due and non-accrual loans at March 31, 2021 and December 31, 2020: 30 - 59 Days Past Due 60 - 89 Days Past Due 90 Days or More Past Due Total Past Due Non-accrual Loans (In thousands) March 31, 2021 Residential one- to four-family $ 728 $ — $ 668 $ 1,396 $ 2,158 Home equity loans and lines of credit — — — — 383 Commercial real estate — — — — 5,768 Construction — — — — — Commercial and industrial — — — — — Consumer 10 4 — 14 — Total $ 738 $ 4 $ 668 $ 1,410 $ 8,309 December 31, 2020 Residential one-to-four family $ - $ — $ — $ — $ 1,876 Home equity loans and lines of credit 95 — 317 412 584 Commercial real estate — — 26 26 4,713 Construction — — — — — Commercial and industrial — — — — — Consumer 38 64 — 102 — Total $ 133 $ 64 $ 343 $ 540 $ 7,173
Summary of Impaired Loans and Additional Information Pertaining to Impaired Loans	The following is a summary of impaired loans at March 31, 2021 and December 31, 2020: Recorded Investment Unpaid Principal Balance Related Allowance (In thousands) March 31, 2021 Impaired loans without a valuation allowance: Residential one- to four-family $ 2,276 $ 2,296 Home equity loans and lines of credit 425 423 Commercial real estate 5,768 5,762 Total 8,469 8,481 Impaired loans with a valuation allowance: Residential one- to four-family 1,536 1,549 $ 132 Commercial real estate 17 17 $ 17 1,553 1,566 149 Total impaired loans $ 10,022 $ 10,047 $ 149 December 31, 2020 Impaired loans without a valuation allowance: Residential one- to four-family $ 2,160 $ 2,181 Home equity loans and lines of credit 626 623 Commercial real estate 4,753 4,751 Total 7,539 7,555 Impaired loans with a valuation allowance: Residential one- to four-family 1,382 1,394 $ 133 Total 1,382 1,394 133 Total impaired loans $ 8,921 $ 8,949 $ 133 Additional information pertaining to impaired loans follows: Average Interest Cash Basis Recorded Income Interest Investment Recognized Recognized (In thousands) Three Months Ended March 31, 2021 Residential one- to four-family $ 3,755 $ 18 $ 39 Home equity loans and lines of credit 424 — — Commercial real estate 5,780 — — Total $ 9,959 $ 18 $ 39 Three Months Ended March 31, 2020 Residential one- to four-family $ 5,336 $ 58 $ 29 Home equity loans and lines of credit 405 1 — Total $ 5,741 $ 59 $ 29
Summary of Financing Receivable, Troubled Debt Restructuring	The Company’s troubled debt restructurings consist primarily of interest rate concessions for periods of three months to thirty years for residential real estate loans, and for periods up to one year for commercial real estate loans. Number of Contracts TDRs Listed as Accrual Number of Contracts TDRs Listed as Non-accrual Number of Contracts Total TDRs (In thousands) March 31, 2021 Residential one- to four-family 12 $ 1,654 4 $ 1,157 16 $ 2,811 Home equity loans and lines of credit 1 42 - — 1 42 Commercial real estate 1 17 - — 1 17 Total 14 $ 1,713 4 $ 1,157 18 $ 2,870 December 31, 2020 Residential one- to four-family $ 12 $ 1,666 $ 4 $ 1,167 16 $ 2,833 Home equity loans and lines of credit 1 42 - — 1 42 Commercial real estate 1 40 - — 1 40 Total 14 1,748 4 $ 1,167 18 $ 2,915
Summary of Company's Loans by Risk Rating	The following table presents the Company’s loans by risk rating at the dates indicated: Residential 1-4 Family Second Mortgages and HELOC Commercial Real Estate Construction Commercial and Industrial Consumer (In thousands) March 31, 2021 Not Rated $ 237,032 $ 48,690 $ — $ — $ — $ 8,724 Loans rated 1 - 3B (Pass rated) — — 133,014 29,975 23,459 — Loans rated 4 1,094 383 8,154 — 410 — Loans rated 5 1,064 — 5,762 — — — $ 239,190 $ 49,073 $ 146,930 $ 29,975 $ 23,869 $ 8,724 December 31, 2020 Not Rated $ 233,773 $ 47,582 $ — $ — $ — $ 10,289 Loans rated 1 - 3B (Pass rated) — — 129,925 31,050 19,828 — Loans rated 4 803 584 9,257 — 431 — Loans rated 5 1,072 — 4,711 — — — $ 235,648 $ 48,166 $ 143,893 $ 31,050 $ 20,259 $ 10,289

Loan Servicing (Tables)

Loan Servicing (Tables)	3 Months Ended
	Mar. 31, 2021
Transfers And Servicing [Abstract]
Summary of Activity Relating to Mortgage Servicing Rights	The following table summarizes the activity relating to mortgage servicing rights (“MSRs”) for the three months ended March 31, 2021 and 2020 (in thousands): March 31, 2021 March 31, 2020 Mortgage servicing rights: Balance at beginning of year $ 15,372 $ 9,484 Additions through originations 2,786 877 Amortization (840 ) (383 ) Balance at end of period $ 17,318 $ 9,978 Valuation allowance: Balance at beginning of year $ 2,995 $ 928 Provision (recovery) (421 ) 1,562 Balance at end of period $ 2,574 $ 2,490 Amortized cost, net $ 14,744 $ 7,488 Fair value $ 15,362 $ 7,515

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Schedule of Calculation of Average Number of Shares Outstanding Used to Calculate Basic and Diluted Earnings (Loss) Per Share	The following table sets forth the calculation of the average number of shares outstanding used to calculate the basic and diluted earnings (loss) per share for the periods indicated: Three Months Ended March 31, 2021 2020 Average number of common shares outstanding 5,429,422 5,550,324 Less: Average unallocated ESOP shares (373,257 ) (392,030 ) Average number of common shares outstanding used to calculate basic earnings per share 5,056,165 5,158,294 Effect of dilutive stock options 198,742 — Average number of common shares outstanding used to calculate dilutive earnings per share 5,254,907 5,158,294

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Grants of Options to Purchase Shares of Common Stock	During the three months ended March 31, 2021 and 2020, the Company made the following grants of options to purchase shares of common stock and used the following assumptions in measuring the fair value of such grants: 2021 2020 Options granted 40,491 79,000 Vesting period (years) 5 5 Expiration period (years) 10 10 Expected volatility 30.98 % 24.94 % Expected life (years) 6.2 6.0 Expected dividend yield — — Risk free interest rate 0.64 % 1.47 % Option fair value $ 6.20 $ 5.74
Summary of Stock Options Activity	A summary of stock option activity for the three months ended March 31, 2021 is presented in the table below: Options Stock Option Grants Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Balance at January 1, 2021 587,168 $ 13.32 8.40 $ — Granted 40,491 20.06 Balance at March 31, 2021 627,659 $ 13.75 8.27 $ 3,923,110 Exercisable at March 31, 2021 177,788 $ 15.01 7.07 $ 887,395 Unrecognized compensation cost (inclusive of directors' options) $ 1,565,435 Weighted average remaining recognition period (years) 2.85
Summary of Activity in Restricted Stock Awards Under Equity Plan	The following table presents the activity in restricted stock awards under the Equity Plan for the three months ended March 31, 2021: Restricted Stock Awards Weighted Average Grant Price Restricted stock awards at January 1, 2021 122,012 $ 12.72 Granted — — Vested (2,500 ) 15.00 Forfeited — — Restricted stock awards at March 31, 2021 119,512 $ 12.67 Unrecognized compensation cost $ 1,219,423 Weighted average remaining recognition period (years) 3.18

Fair Value of Assets and Liab_2

Fair Value of Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Recorded at Fair Value on a Recurring Basis	Assets and liabilities recorded at fair value on a recurring basis are summarized below. Total Level 1 Level 2 Level 3 Fair (In thousands) March 31, 2021 Assets: Securities available for sale $ — $ 54,148 $ — $ 54,148 Portfolio loans (fair value option) — 17,215 — 17,215 Loans held for sale (fair value option) — 93,176 — 93,176 Derivative loan commitments — 2,202 — 2,202 Forward loan sale commitments, including TBAs — 3,619 — 3,619 Liabilities: Forward loan sale commitments, including TBAs — — — — December 31, 2020 Assets: Securities available for sale $ — $ 55,366 $ — $ 55,366 Portfolio loans (fair value option) — 13,780 — 13,780 Loans held for sale (fair value option) — 119,112 — 119,112 Derivative loan commitments — 11,821 — 11,821 Forward loan sale commitments — 44 — 44 Liabilities: Forward loan sale commitments, including TBAs — 2,180 — 2,180
Schedule of Assets Recorded at Fair Value on a Non-Recurring Basis	The following table summarizes the fair value hierarchy used to determine each adjustment and the carrying value of the related assets as of March 31, 2021 and December 31, 2020. Period Ended March 31, 2021 March 31, 2021 Level 1 Level 2 Level 3 Total Gains (Losses) (In thousands) Collateral dependent impaired loans $ — $ — $ 7,462 $ — Mortgage servicing rights — 14,744 — 421 Foreclosed real estate — — 132 — $ — $ 14,744 $ 7,594 $ 421 December 31, 2020 Level 1 Level 2 Level 3 (In thousands) Collateral dependent impaired loans $ — $ — $ 6,318 Mortgage servicing rights — 12,377 — Foreclosed real estate — — 132 $ — $ 12,377 $ 6,450
Summary of Carrying Values, Estimated Fair Values and Placement in Fair Value Hierarchy of Company's Financial Instruments	The estimated fair values, and related carrying amounts, of the Company’s financial instruments are presented below. Certain financial instruments and all non-financial instruments are exempt from disclosure requirements. Accordingly, the aggregate fair value amounts presented herein do not represent the underlying fair value of the Company. This table excludes financial instruments for which the carrying amount approximates fair value. Financial assets for which the fair value approximates carrying value include cash and cash equivalents, and accrued interest receivable. Financial liabilities for which the fair value approximates carrying value include mortgagors’ escrow accounts and accrued interest payable. March 31, 2021 Carrying Fair Amount Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Securities available for sale 54,148 54,148 — 54,148 — Loans held for sale 93,176 93,176 — 93,176 — Loans, net 491,983 498,850 — — 498,850 Derivative assets 5,821 5,821 — 5,821 — Financial liabilities: Deposits $ 560,258 $ 560,498 $ — $ 560,498 $ — FHLBB advances 60,024 60,702 — 60,702 — Derivative liabilities — — — — — December 31, 2020 Carrying Fair Amount Value Level 1 Level 2 Level 3 (In thousands) Financial assets: Securities available for sale 55,366 55,366 — 55,366 — Loans held for sale 119,112 119,112 — 119,112 — Loans, net 483,644 490,914 — — 490,914 Derivative assets 11,865 11,865 — 11,865 — Financial liabilities: Deposits $ 528,307 528,786 $ — $ 528,786 $ — FRB advances 11,431 11,431 — 11,431 — FHLBB advances 61,895 63,071 63,071 Derivative liabilities 2,180 2,180 — 2,180 —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Summary of Financial Instruments Outstanding Contract Amounts Represent Credit Risk	The following financial instruments were outstanding, at the dates indicated, whose contract amounts represent credit risk: March 31, 2021 December 31, 2020 (In thousands) Commitments to originate loans $ 251,697 $ 411,401 Unused lines and letters of credit 75,681 71,458 Unadvanced funds on construction loans 12,343 9,110 Overdraft lines of credit 7,910 7,969

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2021
Segment Reporting [Abstract]
Summary of Segment Information	Segment information as of and for the three months ended March 31, 2021 follows: For the Three Months Ended March 31, 2021 Envision Bank Envision Mortgage Consolidated Total (in thousands) Net interest income $ 4,201 $ 890 $ 5,091 Provision (credit) for loan losses (213 ) — (213 ) Net interest income after provision (credit) for loan losses 4,414 890 5,304 Non-interest income: Customer service fees 340 27 367 Gain on loan origination and sale activities, net (1) — 11,674 11,674 Mortgage servicing fees, net (94 ) 873 779 Other 151 133 284 Total non-interest income 397 12,707 13,104 Non-interest expenses: Salaries and employee benefits 1,802 6,635 8,437 Occupancy and equipment 443 301 744 Other non-interest expenses 1,087 1,683 2,770 Total non-interest expenses 3,332 8,619 11,951 Income before income taxes and elimination of inter-segment profit $ 1,479 $ 4,978 6,457 Elimination of inter-segment profit (681 ) Income before income taxes 5,776 Income tax expense 1,664 Net income $ 4,112 Total assets, March 31, 2021 $ 581,954 $ 156,234 $ 738,188 (1) Before elimination of inter-segment profit. Segment information as of and for the three and three months ended March 31, 2020 follows: For the Three Months Ended March 31, 2020 Envision Bank Envision Mortgage Consolidated Total (in thousands) Net interest income $ 3,994 $ 431 $ 4,425 Provision for loan losses 724 — 724 Net interest income after provision for loan losses 3,270 431 3,701 Non-interest income: Customer service fees 273 33 306 Gain on loan origination and sale activities, net (1) — 7,472 7,472 Mortgage servicing fees, net (87 ) (1,167 ) (1,254 ) Other 140 115 255 Total non-interest income 326 6,453 6,779 Non-interest expenses: Salaries and employee benefits 3,098 5,028 8,126 Occupancy and equipment 404 294 698 Other non-interest expenses 1,146 989 2,135 Total non-interest expenses 4,648 6,311 10,959 Income (loss) before income taxes and elimination of inter-segment profit $ (1,052 ) $ 573 (479 ) Elimination of inter-segment profit (328 ) Loss before income taxes (807 ) Income tax benefit 11 Net loss $ (818 ) Total assets, March 31, 2020 $ 543,586 $ 109,300 $ 652,886 (1) Before elimination of inter-segment profit. (2) Salaries and benefits include the severance and vested stock acceleration costs related to the retirement of the Chief Executive Officer and Chief Financial Officer of the Bank. The cost of this event was $1.38 million, of which $1.03 million was allocated to the Bank segment and the remainder, $344,000, was allocated to the mortgage segment.

Recent Accounting Pronounceme_3

Recent Accounting Pronouncements - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Right-of-use assets related to operating leases	$ 1,100
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets [Member]
Liabilities	$ 637,329	$ 621,253
Other Liabilities [Member]
Liabilities	$ 1,100

Global Pandemic Affecting Ran_3

Global Pandemic Affecting Randolph Bancorp, Inc. - Summary of Lending Activity and Outstanding Balances of PPP Loans and The Associated Pledges (Detail) $ in Thousands	Mar. 31, 2021USD ($)
Financing Receivable Recorded Investment Past Due [Line Items]
PPP Loans Originated	$ 25,547
PPP Loan Balance Outstanding	14,717
Amount Pledged To PPLF	15,387
2020 PPP Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
PPP Loans Originated	15,387
PPP Loan Balance Outstanding	4,557
Amount Pledged To PPLF	15,387
2021 PPP Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
PPP Loans Originated	10,160
PPP Loan Balance Outstanding	$ 10,160

Global Pandemic Affecting Ran_4

Global Pandemic Affecting Randolph Bancorp, Inc.- Additional Information (Detail) - Payment Deferral [Member] $ in Millions	Mar. 31, 2021USD ($)
Commercial Loan [Member]
Unusual Risk Or Uncertainty [Line Items]
Loan, amount	$ 38.2
Residential Real Estate Loans In Portfolio [Member]
Unusual Risk Or Uncertainty [Line Items]
Loan, amount	20.4
Residential Real Estate Loan Serviced For Other [Member]
Unusual Risk Or Uncertainty [Line Items]
Loan, amount	$ 66

Global Pandemic Affecting Ran_5

Global Pandemic Affecting Randolph Bancorp, Inc. - Summary of Loan Portfolio (Detail) - USD ($) $ in Thousands		Mar. 31, 2021	Dec. 31, 2020
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	$ 58,574	$ 57,510
Suspended/Reduction Payment	[2]	11,018	20,562
Resumed Payment	[2]	37,163	30,437
Full Payoff	[3]	10,393	6,511
Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	54,927	53,797
Suspended/Reduction Payment	[2]	10,980	20,494
Resumed Payment	[2]	35,564	28,802
Full Payoff	[3]	8,383	4,501
Residential Real Estate [Member] | One-to-Four Family [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	16,793	15,514
Suspended/Reduction Payment	[2]	4,316	12,974
Resumed Payment	[2]	9,107	2,109
Full Payoff	[3]	3,370	431
Residential Real Estate [Member] | Home Equity Loans and Lines of Credit [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	3,168	3,179
Suspended/Reduction Payment	[2]	423	626
Resumed Payment	[2]	1,479	1,287
Full Payoff	[3]	1,266	1,266
Residential Real Estate [Member] | Construction [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	350	350
Suspended/Reduction Payment	[2]		350
Resumed Payment	[2]	350
Residential Real Estate [Member] | Commercial Real Estate Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	34,616	34,754
Suspended/Reduction Payment	[2]	6,241	6,544
Resumed Payment	[2]	24,628	25,406
Full Payoff	[3]	3,747	2,804
Commercial and Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	3,579	3,645
Resumed Payment	[2]	1,569	1,635
Full Payoff	[3]	2,010	2,010
Consumer [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Deferrals Granted	[1]	68	68
Suspended/Reduction Payment	[2]	38	$ 68
Resumed Payment	[2]	$ 30
[1]	This column equals the current outstanding balance of loans that received a deferral, plus the balance of loans that were deferred and were paid off in full.
[2]	These two columns are the current balance of all loans that received a deferral. The Suspended/Reduced Payment columns represents loans currently in a deferral period and the Resumed Payment columns represents loans that are no longer in a deferral period and have resumed normal payment.
[3]	This column represents the balance of deferred loans that were paid off in full.

Global Pandemic Affecting Ran_6

Global Pandemic Affecting Randolph Bancorp, Inc. - Schedule of Past Due and Non-Accrual Loans by Loan Category (Detail) - USD ($) $ in Thousands		Mar. 31, 2021	Dec. 31, 2020
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	$ 34,692	$ 37,442
Special Mention	[1]	8,254	9,375
Sub-standard	[1]	5,235	4,182
Non-accrual	[2]	5,430	4,378
Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	33,465	36,170
Special Mention	[1]	7,844	8,944
Sub-standard	[1]	5,235	4,182
Non-accrual	[2]	5,430	4,378
Residential Real Estate [Member] | One-to-Four Family [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	13,228	14,887
Special Mention	[1]	195	196
Non-accrual	[2]	195	196
Residential Real Estate [Member] | Home Equity Loans and Lines of Credit [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	1,902	1,913
Residential Real Estate [Member] | Construction [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	350	350
Residential Real Estate [Member] | Commercial Real Estate Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	17,985	19,020
Special Mention	[1]	7,649	8,748
Sub-standard	[1]	5,235	4,182
Non-accrual	[2]	5,235	4,182
Commercial and Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	1,159	1,204
Special Mention	[1]	410	431
Consumer [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Pass Rated / Not Rated	[1]	$ 68	$ 68
[1]	These three columns indicate the risk rating and subsequent outstanding balance of loans that have received a deferral. The Pass Rated/Not Rated, Special Mention and Substandard columns reconcile to the Suspended Payment/Reduced Payment and Resumed Payment columns in the preceding table.
[2]	Nonaccrual loans are risk rated as either special mention or substandard loans and are included as a balance in those columns.

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) and Related Tax Effects (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total other comprehensive income (loss)	$ (794)	$ 1,561
Accumulated other comprehensive income, net of tax	101		$ 895
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gain	795		1,713
Other comprehensive Loss, Tax effect	(193)		(313)
Total other comprehensive income (loss)	602		1,400
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gain	(700)		(712)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gain	246		254
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gain	(454)		(458)
Other comprehensive Loss, Tax effect	(47)		(47)
Total other comprehensive income (loss)	$ (501)		$ (505)

Securities Available for Sale -

Securities Available for Sale - Schedule of Amortized Cost and Fair Value of Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 53,353	$ 53,654
Gross Unrealized Gains	1,112	1,712
Gross Unrealized Losses	(317)
Fair Value	54,148	55,366
Debt Securities [Member] | U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,913
Gross Unrealized Losses	(90)
Fair Value	3,823
Debt Securities [Member] | US Government-sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,993	1,993
Gross Unrealized Gains		3
Gross Unrealized Losses	(2)
Fair Value	1,991	1,996
Debt Securities [Member] | Corporate [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,286	4,300
Gross Unrealized Gains	15	56
Gross Unrealized Losses	(5)
Fair Value	4,296	4,356
Debt Securities [Member] | Municipal [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	595	595
Gross Unrealized Gains	3	5
Fair Value	598	600
Debt Securities [Member] | Residential Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	29,023	32,538
Gross Unrealized Gains	623	919
Gross Unrealized Losses	(220)
Fair Value	29,426	33,457
Debt Securities [Member] | Commercial Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,825	8,857
Gross Unrealized Gains	361	525
Fair Value	9,186	9,382
Debt Securities [Member] | Commercial Mortgage Backed Securities, U.S. Government-guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	559	977
Gross Unrealized Gains	9	24
Fair Value	568	1,001
Debt Securities [Member] | Collateralized Mortgage Obligations, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	944	996
Gross Unrealized Gains	41	52
Fair Value	985	1,048
Debt Securities [Member] | Collateralized Mortgage Obligations, US Government Guaranteed [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,215	3,398
Gross Unrealized Gains	60	128
Fair Value	$ 3,275	$ 3,526

Securities Available for Sale_2

Securities Available for Sale - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021USD ($)Debt_Security	Mar. 31, 2020USD ($)
Investments Debt And Equity Securities [Abstract]
Proceeds from sales of available-for-sale securities | $	$ 0	$ 0
Number of debt securities with unrealized losses | Debt_Security	11
Unrealized losses debt securities aggregate depreciation percentage	1.73%

Securities Available for Sale_3

Securities Available for Sale - Investments Classified by Contractual Maturity Date (Detail) $ in Thousands	Mar. 31, 2021USD ($)
Available-for-sale Securities, Debt Maturities, Amortized Cost
Within 1 year	$ 1,001
After 1 year through 5 years	4,804
After 5 years through 10 years	4,982
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis, Total	10,787
Mortgage-backed securities	42,566
Available-for-sale Debt Securities, Amortized Cost Basis, Total	53,353
Available-for-sale Securities, Debt Maturities, Fair Value
Within 1 year	1,011
After 1 year through 5 years	4,811
After 5 years through 10 years	4,886
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Fair Value Total	10,708
Mortgage-backed securities	43,440
Available-for-sale Securities, Debt Securities, Fair Value Total	$ 54,148

Securities Available for Sale_4

Securities Available for Sale - Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value (Detail) - Debt Securities [Member] $ in Thousands	Mar. 31, 2021USD ($)
Schedule of Available-for-sale Securities [Line Items]
Less Than Twelve Months, Gross Unrealized Losses	$ (317)
Less Than Twelve Months, Fair Value	17,972
U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than Twelve Months, Gross Unrealized Losses	(90)
Less Than Twelve Months, Fair Value	3,823
US Government-sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than Twelve Months, Gross Unrealized Losses	(2)
Less Than Twelve Months, Fair Value	1,992
Corporate [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than Twelve Months, Gross Unrealized Losses	(5)
Less Than Twelve Months, Fair Value	1,801
Residential Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than Twelve Months, Gross Unrealized Losses	(220)
Less Than Twelve Months, Fair Value	$ 10,356

Loans and Allowance for Loan _3

Loans and Allowance for Loan Losses - Summary of Loan Portfolio (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 497,761	$ 489,305
Allowance for loan losses	(6,563)	(6,784)
Net deferred loan costs and fees, and purchase premiums	785	1,123
Loans, net	491,983	483,644
Real Estate Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	465,168	458,757
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	146,930	143,893
Commercial Real Estate Loans [Member] | Real Estate Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	146,930	143,893
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	23,869	20,259
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	8,724	10,289
One-to-Four Family [Member] | Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	239,190	235,648
One-to-Four Family [Member] | Residential Real Estate [Member] | Real Estate Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	239,190	235,648
Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member] | Real Estate Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	49,073	48,166
Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	29,975	31,050
Construction [Member] | Real Estate Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 29,975	$ 31,050

Loans and Allowance for Loan _4

Loans and Allowance for Loan Losses - Summary of Activity in the Allowance for Loan Losses by Loan Category (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 6,784	$ 4,280
Provision (credit) for loan losses	(213)	724
Loans charged-off	(10)	(16)
Recoveries	2	8
Ending balance	6,563	4,996
Commercial Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	3,402	1,840
Provision (credit) for loan losses	(12)	401
Ending balance	3,390	2,241
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	416	235
Provision (credit) for loan losses	(15)	45
Ending balance	401	280
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	127	128
Provision (credit) for loan losses	(12)	21
Loans charged-off	(10)	(16)
Recoveries		4
Ending balance	105	137
One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,646	1,096
Provision (credit) for loan losses	(126)	123
Recoveries	2	4
Ending balance	1,522	1,223
Second Mortgages and HELOC [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	442	289
Provision (credit) for loan losses	(17)	54
Ending balance	425	343
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	751	692
Provision (credit) for loan losses	(31)	80
Ending balance	$ 720	$ 772

Loans and Allowance for Loan _5

Loans and Allowance for Loan Losses - Summary of Additional Information Pertaining to the Allowance for Loan Losses (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for impaired loans	$ 149	$ 133
Allowance for non-impaired loans	6,414	6,651
Total allowance for loan losses	6,563	6,784	$ 4,996	$ 4,280
Impaired loans	10,047	8,949
Non-impaired loans	487,714	480,356
Total loans	497,761	489,305
Commercial Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for impaired loans	17
Allowance for non-impaired loans	3,373	3,402
Total allowance for loan losses	3,390	3,402	2,241	1,840
Impaired loans	5,779	4,751
Non-impaired loans	141,151	139,142
Total loans	146,930	143,893
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	401	416
Total allowance for loan losses	401	416	280	235
Non-impaired loans	23,869	20,259
Total loans	23,869	20,259
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	105	127
Total allowance for loan losses	105	127	137	128
Non-impaired loans	8,724	10,289
Total loans	8,724	10,289
One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for impaired loans	132	133
Allowance for non-impaired loans	1,390	1,513
Total allowance for loan losses	1,522	1,646	1,223	1,096
Impaired loans	3,845	3,575
Non-impaired loans	235,345	232,073
Total loans	239,190	235,648
Second Mortgages and HELOC [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	425	442
Total allowance for loan losses	425	442	343	289
Impaired loans	423	623
Non-impaired loans	48,650	47,543
Total loans	49,073	48,166
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for non-impaired loans	720	751
Total allowance for loan losses	720	751	$ 772	$ 692
Non-impaired loans	29,975	31,050
Total loans	$ 29,975	$ 31,050

Loans and Allowance for Loan _6

Loans and Allowance for Loan Losses - Schedule of Past Due and Non-Accrual Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	$ 1,410	$ 540
Non-accrual Loans	8,309	7,173
Consumer [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	14	102
One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	1,396
Non-accrual Loans	2,158	1,876
Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		412
Non-accrual Loans	383	584
Commercial Real Estate Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		26
Non-accrual Loans	5,768	4,713
30 - 59 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	738	133
30 - 59 Days Past Due [Member] | Consumer [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	10	38
30 - 59 Days Past Due [Member] | One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	728
30 - 59 Days Past Due [Member] | Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		95
60 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	4	64
60 - 89 Days Past Due [Member] | Consumer [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	4	64
90 Days or More Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	668	343
90 Days or More Past Due [Member] | One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due	$ 668
90 Days or More Past Due [Member] | Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		317
90 Days or More Past Due [Member] | Commercial Real Estate Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		$ 26

Loans and Allowance for Loan _7

Loans and Allowance for Loan Losses - Summary of Impaired Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Impaired [Line Items]
Recorded Investment without a valuation allowance	$ 8,469	$ 7,539
Unpaid Principal Balance without a valuation allowance	8,481	7,555
Recorded Investment with a valuation allowance	1,553	1,382
Unpaid Principal Balance with a valuation allowance	1,566	1,394
Related Allowance, Total impaired loans	149	133
Recorded Investment, Total impaired loans	10,022	8,921
Unpaid Principal Balance, Total impaired loans	10,047	8,949
Commercial Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment without a valuation allowance	5,768	4,753
Unpaid Principal Balance without a valuation allowance	5,762	4,751
Recorded Investment with a valuation allowance	17
Unpaid Principal Balance with a valuation allowance	17
Related Allowance, Total impaired loans	17
One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment without a valuation allowance	2,276	2,160
Unpaid Principal Balance without a valuation allowance	2,296	2,181
Recorded Investment with a valuation allowance	1,536	1,382
Unpaid Principal Balance with a valuation allowance	1,549	1,394
Related Allowance, Total impaired loans	132	133
Home Equity Loans and Lines of Credit [Member] | Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment without a valuation allowance	425	626
Unpaid Principal Balance without a valuation allowance	$ 423	$ 623

Loans and Allowance for Loan _8

Loans and Allowance for Loan Losses - Summary of Additional Information Pertaining to Impaired Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 9,959	$ 5,741
Interest Income Recognized	18	59
Cash Basis Interest Recognized	39	29
Residential Real Estate [Member] | One-to-Four Family [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	3,755	5,336
Interest Income Recognized	18	58
Cash Basis Interest Recognized	39	29
Residential Real Estate [Member] | Home Equity Loans and Lines of Credit [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	424	405
Interest Income Recognized		$ 1
Commercial Real Estate Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 5,780

Loans and Allowance for Loan _9

Loans and Allowance for Loan Losses - Additional Information (Detail)	3 Months Ended		12 Months Ended
	Mar. 31, 2021USD ($)ContractTDR	Mar. 31, 2020USD ($)TDR	Dec. 31, 2020USD ($)Contract
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired loans, additional funds committed	$ 0
Loans subject to troubled debt restructurings | TDR	0	0
Allowances related to troubled debt restructurings	$ 0	$ 0
Number of Contracts | Contract	18		18
Total TDRs	$ 2,870,000		$ 2,915,000
30 - 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings defaulted over 30 days past due	$ 0	$ 0
Residential Real Estate [Member] | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts | TDR	2
Residential Real Estate [Member] | Performing Financial Instruments [Member] | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total TDRs	$ 297,000
Residential Real Estate [Member] | Nonperforming Financial Instruments [Member] | Payment Deferral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total TDRs	$ 196,000
Residential Real Estate [Member] | Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring, interest rate concession period	3 months
Residential Real Estate [Member] | Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring, interest rate concession period	30 years
Commercial Real Estate Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Contracts | Contract	1		1
Total TDRs	$ 17,000		$ 40,000
Commercial Real Estate Loans [Member] | Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructuring, interest rate concession period	1 year

Loans and Allowance for Loan_10

Loans and Allowance for Loan Losses - Schedule of Troubled Debt Restructuring (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021USD ($)OfficeLeaseContract	Dec. 31, 2020USD ($)OfficeLeaseContract
Financing Receivable Modifications [Line Items]
Number of Contracts | Contract	18	18
Total TDRs	$ 2,870	$ 2,915
TDRs Listed as Accrual [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Office	14	14
Total TDRs	$ 1,713	$ 1,748
TDRs Listed as Non-accrual [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Lease	4	4
Total TDRs	$ 1,157	$ 1,167
Residential Real Estate [Member] | One-to-Four Family [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Contract	16	16
Total TDRs	$ 2,811	$ 2,833
Residential Real Estate [Member] | Home Equity Loans and Lines of Credit [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Contract	1	1
Total TDRs	$ 42	$ 42
Residential Real Estate [Member] | TDRs Listed as Accrual [Member] | One-to-Four Family [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Office	12	12
Total TDRs	$ 1,654	$ 1,666
Residential Real Estate [Member] | TDRs Listed as Accrual [Member] | Home Equity Loans and Lines of Credit [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Office	1	1
Total TDRs	$ 42	$ 42
Residential Real Estate [Member] | TDRs Listed as Non-accrual [Member] | One-to-Four Family [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Lease	4	4
Total TDRs	$ 1,157	$ 1,167
Commercial Real Estate Loans [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Contract	1	1
Total TDRs	$ 17	$ 40
Commercial Real Estate Loans [Member] | TDRs Listed as Accrual [Member]
Financing Receivable Modifications [Line Items]
Number of Contracts | Office	1	1
Total TDRs	$ 17	$ 40

Loans and Allowance for Loan_11

Loans and Allowance for Loan Losses - Summary of Company's Loans by Risk Rating (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$ 497,761	$ 489,305
Commercial Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	146,930	143,893
Commercial Real Estate Loans [Member] | Pass [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	133,014	129,925
Commercial Real Estate Loans [Member] | Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	8,154	9,257
Commercial Real Estate Loans [Member] | Substandard [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	5,762	4,711
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	23,869	20,259
Commercial and Industrial [Member] | Pass [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	23,459	19,828
Commercial and Industrial [Member] | Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	410	431
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	8,724	10,289
Consumer [Member] | Note Rated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	8,724	10,289
One-to-Four Family [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	239,190	235,648
One-to-Four Family [Member] | Residential Real Estate [Member] | Note Rated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	237,032	233,773
One-to-Four Family [Member] | Residential Real Estate [Member] | Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,094	803
One-to-Four Family [Member] | Residential Real Estate [Member] | Substandard [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,064	1,072
Second Mortgages and HELOC [Member] | Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	49,073	48,166
Second Mortgages and HELOC [Member] | Residential Real Estate [Member] | Note Rated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	48,690	47,582
Second Mortgages and HELOC [Member] | Residential Real Estate [Member] | Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	383	584
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	29,975	31,050
Construction [Member] | Pass [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$ 29,975	$ 31,050

Loan Servicing - Additional Inf

Loan Servicing - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Transfers And Servicing [Abstract]
Unpaid principal balances of residential mortgage loans serviced for others	$ 1,940,000,000		$ 1,760,000,000
Custodial Escrow balances	17,000,000		$ 14,200,000
Increase (reduced) the valuation allowance of mortgage servicing rights	$ (421,000)	$ 1,562,000

Loan Servicing - Summary of Act

Loan Servicing - Summary of Activity Relating to Mortgage Servicing Rights (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Mortgage servicing rights:
Balance at beginning of year	$ 15,372	$ 9,484
Additions through originations	2,786	877
Amortization	(840)	(383)
Balance at end of period	17,318	9,978
Valuation allowance:
Balance at beginning of year	2,995	928
Provision (recovery)	(421)	1,562
Balance at end of period	2,574	2,490
Amortized cost, net	14,744	7,488
Fair value	$ 15,362	$ 7,515

On-Balance Sheet Derivative I_2

On-Balance Sheet Derivative Instruments and Hedging Activities - Additional Information (Detail) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Derivative Loan Commitments [Member]
Derivative [Line Items]
Derivative, Notional amount	$ 239,509,000	$ 396,551,000
Undesignated Forward Loan Sale Commitments and TBA Securities [Member]
Derivative [Line Items]
Derivative, Notional amount	237,778,000	390,248,000
Other Assets [Member] | Derivative Loan Commitments [Member]
Derivative [Line Items]
Derivative fair value, Asset	2,202,000	11,821,000
Other Assets [Member] | Undesignated Forward Loan Sale Commitments and TBA Securities [Member]
Derivative [Line Items]
Derivative fair value, Asset	3,619,000	44,000
Other Liabilities [Member] | Undesignated Forward Loan Sale Commitments and TBA Securities [Member]
Derivative [Line Items]
Derivative fair value, Liability	$ 0	$ 2,180,000

Employee Stock Ownership Plan -

Employee Stock Ownership Plan - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Employee Stock Ownership Plan E S O P Disclosures [Line Items]
Loan repaid term	25 years
Number of allocated shares	18,780
Annual allocation of shares, expiration year	2040
ESOP expense	$ 94,000	$ 68,000
Unallocated shares	370,967
Unallocated shares, value	$ 7,419,000
Common Stock [Member] | Initial Public Offering [Member]
Employee Stock Ownership Plan E S O P Disclosures [Line Items]
Sale of stock, price per share	$ 10
The Randolph Savings Charitable Foundation, Inc. [Member] | Initial Public Offering [Member]
Employee Stock Ownership Plan E S O P Disclosures [Line Items]
Sale of share in employee stock ownership plan	469,498

Share Repurchase Program - Addi

Share Repurchase Program - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
	Oct. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Class Of Stock [Line Items]
Cost of shares repurchased		$ 2,652,000	$ 1,195,000
October 2020 Share Repurchase Program [Member]
Class Of Stock [Line Items]
Stock repurchase program percentage of outstanding shares repurchased	10.00%
Number of shares authorized to repurchase	552,000
Number of shares repurchased		159,640
Cost of shares repurchased		$ 3,156,000

Earnings (Loss) Per Share - Sch

Earnings (Loss) Per Share - Schedule of Calculation of Average Number of Shares Outstanding Used to Calculate Basic and Diluted Earnings (Loss) Per Share (Detail) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Average number of common shares outstanding	5,429,422	5,550,324
Less: Average unallocated ESOP shares	(373,257)	(392,030)
Average number of common shares outstanding used to calculate basic earnings per share	5,056,165	5,158,294
Effect of dilutive stock options	198,742
Average number of common shares outstanding used to calculate dilutive earnings per share	5,254,907	5,158,294

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021USD ($)shares	Mar. 31, 2020USD ($)Officershares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted	40,491	79,000
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option term	10 years	10 years
Options and awards vesting period	5 years	5 years
Stock-based compensation expense | $	$ 142,000	$ 309,000
Stock Options [Member] | Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Amount attributable to accelerated vesting of units | $		$ 233,000
Number of officer | Officer		2
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense | $	$ 125,000	$ 622,000
Restricted Stock [Member] | Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Amount attributable to accelerated vesting of units | $		$ 450,000
Number of officer | Officer		2
Two Thousand Seventeen Stock Option and Incentive Plan [Member] | Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance	586,872
Stock option term	10 years
Two Thousand Seventeen Stock Option and Incentive Plan [Member] | Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance	234,749
Two Thousand Seventeen Stock Option and Incentive Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and awards vesting period	3 years
Two Thousand Seventeen Stock Option and Incentive Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and awards vesting period	5 years
2020 Inducement Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options and awards vesting period	5 years
2020 Inducement Plan [Member] | Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted	44,118
2020 Inducement Plan [Member] | Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock awards granted	15,000

Stock Based Compensation - Summ

Stock Based Compensation - Summary of Grants of Options to Purchase Shares of Common Stock (Detail) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted	40,491	79,000
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period (years)	5 years	5 years
Expiration period (years)	10 years	10 years
Expected volatility	30.98%	24.94%
Expected life (years)	6 years 2 months 12 days	6 years
Risk free interest rate	0.64%	1.47%
Option fair value	$ 6.20	$ 5.74

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Options Activity (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Stock Option Grants
Beginning Balance	587,168
Granted	40,491	79,000
Ending Balance	627,659		587,168
Exercisable at March 31, 2021	177,788
Unrecognized compensation cost (inclusive of directors' options)	$ 1,565,435
Weighted Average Exercise Price
Beginning Balance	$ 13.32
Granted	20.06
Ending Balance	13.75		$ 13.32
Exercisable at March 31, 2021	$ 15.01
Weighted Average Remaining Contractual Term and Aggregate Intrinsic Value
Weighted Average Remaining Contractual Term	8 years 3 months 7 days		8 years 4 months 24 days
Weighted Average Remaining Contractual Term, Exercisable	7 years 25 days
Aggregate Intrinsic Value, Outstanding	$ 3,923,110
Aggregate Intrinsic Value, Exercisable	$ 887,395
Stock Options [Member]
Stock Option Grants
Weighted average remaining recognition period (years)	2 years 10 months 6 days

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Activity in Restricted Stock Awards Under Equity Plan (Detail)	3 Months Ended
	Mar. 31, 2021USD ($)$ / sharesshares
Restricted Stock Awards
Beginning Balance | shares	122,012
Vested | shares	(2,500)
Ending Balance | shares	119,512
Unrecognized compensation cost | $	$ 1,219,423
Weighted Average Grant Price
Beginning Balance | $ / shares	$ 12.72
Vested | $ / shares	15
Ending Balance | $ / shares	$ 12.67
Restricted Stock [Member]
Restricted Stock Awards
Weighted average remaining recognition period (years)	3 years 2 months 4 days

Fair Value of Assets and Liab_3

Fair Value of Assets and Liabilities - Schedule of Assets and Liabilities Recorded at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale, at fair value	$ 54,148	$ 55,366
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale, at fair value	54,148	55,366
Fair value, Loans held for sale	93,176	119,112
Derivative assets	5,821	11,865
Derivative liabilities		2,180
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale, at fair value	54,148	55,366
Fair value, Portfolio loans	17,215	13,780
Fair value, Loans held for sale	93,176	119,112
Fair Value, Measurements, Recurring [Member] | Derivative Loan Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	2,202	11,821
Fair Value, Measurements, Recurring [Member] | Forward Loan Sale Commitments, including TBAs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	3,619
Derivative liabilities		2,180
Fair Value, Measurements, Recurring [Member] | Forward Loan Sale Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		44
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale, at fair value	54,148	55,366
Fair value, Portfolio loans	17,215	13,780
Fair value, Loans held for sale	93,176	119,112
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Derivative Loan Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	2,202	11,821
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Forward Loan Sale Commitments, including TBAs [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$ 3,619
Derivative liabilities		2,180
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Forward Loan Sale Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		$ 44

Fair Value of Assets and Liab_4

Fair Value of Assets and Liabilities - Additional information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, assets, level 1 to level 2 transfers, amount	$ 0	$ 0
Fair value, assets, level 2 to level 1 transfers, amount	0	0
Fair value, liabilities, level 1 to level 2 transfers, amount	0	0
Fair value, liabilities, level 2 to level 1 transfers, amount	0	0
Increase (decrease) in valuation allowance of mortgage servicing rights	421,000	$ (1,562,000)
Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities measured at fair value on nonrecurring basis	$ 0		$ 0

Fair Value of Assets and Liab_5

Fair Value of Assets and Liabilities - Schedule of Assets Recorded at Fair Value on a Non-Recurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, fair value	$ 15,362		$ 7,515
Fair Value, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Gains (losses) on assets held, mortgage servicing rights	421
Gains (Losses) on assets held	421
Fair Value, Nonrecurring | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights, fair value	14,744	$ 12,377
Assets, Fair Value Disclosure	14,744	12,377
Fair Value, Nonrecurring | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value, Collateral dependent impaired loans	7,462	6,318
Fair value, Foreclosed real estate	132	132
Assets, Fair Value Disclosure	$ 7,594	$ 6,450

Fair Value of Assets and Liab_6

Fair Value of Assets and Liabilities - Summary of Carrying Values, Estimated Fair Values and Placement in Fair Value Hierarchy of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financial assets:
Securities available for sale	$ 54,148	$ 55,366
Level 2 [Member]
Financial assets:
Securities available for sale	54,148	55,366
Loans held for sale	93,176	119,112
Derivative assets	5,821	11,865
Financial liabilities:
Deposits	560,498	528,786
FRB advances		11,431
FHLBB advances	60,702	63,071
Derivative liabilities		2,180
Level 3 [Member]
Financial assets:
Loans, net	498,850	490,914
Carrying Amount [Member]
Financial assets:
Securities available for sale	54,148	55,366
Loans held for sale	93,176	119,112
Loans, net	491,983	483,644
Derivative assets	5,821	11,865
Financial liabilities:
Deposits	560,258	528,307
FRB advances		11,431
FHLBB advances	60,024	61,895
Derivative liabilities		2,180
Fair Value [Member]
Financial assets:
Securities available for sale	54,148	55,366
Loans held for sale	93,176	119,112
Loans, net	498,850	490,914
Derivative assets	5,821	11,865
Financial liabilities:
Deposits	560,498	528,786
FRB advances		11,431
FHLBB advances	$ 60,702	63,071
Derivative liabilities		$ 2,180

Commitments and Contingencies -

Commitments and Contingencies - Summary of Financial Instruments Outstanding Contract Amounts Represent Credit Risk (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Commitments to Originate Loans [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Financial instruments with off-balance-sheet risk	$ 251,697	$ 411,401
Unused Lines and Letters of Credit [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Financial instruments with off-balance-sheet risk	75,681	71,458
Unadvanced Funds on Construction Loans [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Financial instruments with off-balance-sheet risk	12,343	9,110
Overdraft Lines of Credit [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Financial instruments with off-balance-sheet risk	$ 7,910	$ 7,969

Segment Information - Additiona

Segment Information - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2021USD ($)OfficeSegment	Mar. 31, 2020USD ($)
Segment Reporting Information [Line Items]
Number of business segments | Segment	2
Number of branch offices | Office	5
Servicing fees amount	$ (779,000)	$ 1,254,000
Envision Mortgage [Member]
Segment Reporting Information [Line Items]
Premium percentage for new loans	1.50%	1.50%
Premium income	$ 681,000	$ 328,000
Percentage of fees for HELOC	1.00%	1.00%
Servicing fees amount	$ (873,000)	$ 1,167,000
Envision Bank [Member]
Segment Reporting Information [Line Items]
Percentage of loan servicing fees	0.14%	0.14%
Servicing fees amount	$ 94,000	$ 87,000

Segment Information - Summary o

Segment Information - Summary of Segment Information (Detail) - USD ($)		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net interest income		$ 5,091,000	$ 4,425,000
Provision (credit) for loan losses		(213,000)	724,000
Net interest income after provision (credit) for loan losses		5,304,000	3,701,000
Non-interest income:
Customer service fees		367,000	306,000
Gain on loan origination and sale activities, net	[1]	11,674,000	7,472,000
Mortgage servicing fees, net		779,000	(1,254,000)
Other		284,000	255,000
Total non-interest income		13,104,000	6,779,000
Non-interest expenses:
Salaries and employee benefits		8,437,000	8,126,000
Occupancy and equipment		744,000	698,000
Other non-interest expenses		2,770,000	2,135,000
Total non-interest expenses		11,951,000	10,959,000
Income before income taxes and elimination of inter-segment profit		6,457,000	(479,000)
Elimination of inter-segment profit		(681,000)	(328,000)
Income (loss) before income taxes		5,776,000	(807,000)
Income tax expense		1,664,000	11,000
Net income (loss)		4,112,000	(818,000)
Total assets		738,188,000	652,886,000	$ 721,072,000
Envision Bank [Member]
Segment Reporting Information [Line Items]
Net interest income		4,201,000	3,994,000
Provision (credit) for loan losses		(213,000)	724,000
Net interest income after provision (credit) for loan losses		4,414,000	3,270,000
Non-interest income:
Customer service fees		340,000	273,000
Mortgage servicing fees, net		(94,000)	(87,000)
Other		151,000	140,000
Total non-interest income		397,000	326,000
Non-interest expenses:
Salaries and employee benefits		1,802,000	3,098,000
Occupancy and equipment		443,000	404,000
Other non-interest expenses		1,087,000	1,146,000
Total non-interest expenses		3,332,000	4,648,000
Income before income taxes and elimination of inter-segment profit		1,479,000	(1,052,000)
Total assets		581,954,000	543,586,000
Envision Mortgage [Member]
Segment Reporting Information [Line Items]
Net interest income		890,000	431,000
Net interest income after provision (credit) for loan losses		890,000	431,000
Non-interest income:
Customer service fees		27,000	33,000
Gain on loan origination and sale activities, net	[1]	11,674,000	7,472,000
Mortgage servicing fees, net		873,000	(1,167,000)
Other		133,000	115,000
Total non-interest income		12,707,000	6,453,000
Non-interest expenses:
Salaries and employee benefits		6,635,000	5,028,000
Occupancy and equipment		301,000	294,000
Other non-interest expenses		1,683,000	989,000
Total non-interest expenses		8,619,000	6,311,000
Income before income taxes and elimination of inter-segment profit		4,978,000	573,000
Total assets		$ 156,234,000	$ 109,300,000
[1]	Before elimination of inter-segment profit.

Segment Information - Summary_2

Segment Information - Summary of Segment Information (Parenthetical) (Detail)	3 Months Ended
	Mar. 31, 2020USD ($)
Salaries and benefits cost including the severance and vested stock acceleration costs	$ 1,380,000
Bank Segment [Member]
Salaries and benefits cost including the severance and vested stock acceleration costs	1,030,000
Mortgage Segment [Member]
Salaries and benefits cost including the severance and vested stock acceleration costs	$ 344,000