Territorial Bancorp (TBNK) 10-K 17 Mar 23 2022 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Feb. 28, 2023	Jun. 30, 2022
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2022
Entity File Number	001-34403
Entity Registrant Name	Territorial Bancorp Inc.
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	26-4674701
Entity Address, Address Line One	1003 Bishop Street, Pauahi Tower Suite 500
Entity Address, City or Town	Honolulu
Entity Address, State or Province	HI
Entity Address, Postal Zip Code	96813
City Area Code	808
Local Phone Number	946-1400
Title of 12(b) Security	Common stock
Trading Symbol	TBNK
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Public Float			$ 172.4
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		9,071,076
Auditor Name	Moss Adams LLP
Auditor Firm ID	659
Auditor Location	Portland, Oregon
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Entity Central Index Key	0001447051
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
ASSETS
Cash and cash equivalents	$ 40,553	$ 99,859
Investment securities available for sale, at fair value	20,821
Investment securities held to maturity, at amortized cost (fair value of $591,084 and $634,987 at December 31, 2022 and December 31, 2021, respectively)	717,773	636,442
Loans receivable, net	1,294,764	1,302,824
Federal Home Loan Bank stock, at cost	8,197	8,173
Federal Reserve Bank stock, at cost	3,170	3,158
Accrued interest receivable	6,115	5,786
Premises and equipment, net	7,599	4,065
Right-of-use asset, net	14,498	9,982
Bank-owned life insurance	47,783	51,423
Deferred income tax assets, net	1,643	1,927
Prepaid expenses and other assets	6,676	6,963
Total assets	2,169,592	2,130,602
Liabilities:
Deposits	1,716,152	1,681,828
Advances from the Federal Home Loan Bank	141,000	141,000
Securities sold under agreements to repurchase	10,000	10,000
Accounts payable and accrued expenses	24,180	22,638
Lease liability	15,295	10,744
Income taxes payable	838	1,863
Advance payments by borrowers for taxes and insurance	5,577	6,207
Total liabilities	1,913,042	1,874,280
Commitments and contingencies
Stockholders' Equity:
Preferred stock, $0.01 par value; authorized 50,000,000 shares, no shares issued or outstanding
Common stock, $0.01 par value; authorized 100,000,000 shares; issued and outstanding 9,071,076 and 9,324,060 shares at December 31, 2022 and December 31, 2021, respectively	91	93
Additional paid-in capital	51,825	56,951
Unearned ESOP shares	(2,936)	(3,425)
Retained earnings	215,314	208,227
Accumulated other comprehensive loss	7,744	5,524
Total stockholders' equity	256,550	256,322
Total liabilities and stockholders' equity	$ 2,169,592	$ 2,130,602

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Consolidated Balance Sheets
Investment securities held to maturity, fair value (in dollars)	$ 591,084	$ 634,987
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized shares	50,000,000	50,000,000
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock, par value (in dollars per share)	$ 0.01
Common stock, authorized shares	100,000,000
Common stock, shares issued	9,071,076	9,324,060
Common stock, shares outstanding	9,071,076	9,324,060

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Interest income:
Loans	$ 45,318	$ 48,740
Investment securities	16,211	10,729
Other investments	1,173	832
Total interest income	62,702	60,301
Interest expense:
Deposits	4,925	3,975
Advances from the Federal Home Loan Bank	2,107	2,117
Securities sold under agreements to repurchase	183	184
Total interest expense	7,215	6,276
Net interest income	55,487	54,025
Reversal of provision for loan losses	(576)	(1,592)
Net interest income after reversal of provision for loan losses	56,063	55,617
Noninterest income:
Service and other fees	1,416	2,463
Income on bank-owned life insurance	792	779
Gain on sale of investment securities		1,840
Net gain (loss) on sale of loans	(3)	663
Other	2,004	727
Total noninterest income	4,209	6,472
Noninterest expense:
Salaries and employee benefits	22,259	22,091
Occupancy	6,708	6,486
Equipment	5,006	4,483
Federal deposit insurance premiums	573	565
Other general and administrative expenses	4,252	4,661
Total noninterest expense	38,798	38,286
Income before income taxes	21,474	23,803
Income taxes	5,318	6,373
Net income	$ 16,156	$ 17,430
Basic earnings per share (in dollars per share)	$ 1.81	$ 1.92
Diluted earnings per share (in dollars per share)	1.80	1.90
Cash dividends declared per common share (in dollars per share)	$ 1.02	$ 1.02
Basic weighted-average shares outstanding (in shares)	8,865,946	9,059,204
Diluted weighted-average shares outstanding (in shares)	8,920,714	9,110,335
Service and Other Fees
Noninterest income:
Service and other fees	$ 1,416	$ 2,463

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Consolidated Statements of Comprehensive Income
Net income	$ 16,156	$ 17,430
Unfunded pension liability gain (loss), net of tax	(222)	3,443
Unrealized loss on securities	(1,998)	(3)
Amount reclassified from other comprehensive income		(273)
Total other comprehensive loss, net of tax	(2,220)	3,167
Comprehensive income	$ 13,936	$ 20,597

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Unearned ESOP Shares	Retained Earnings	Accumulated Other Comprehensive (Loss)/Income	Total
Balance at Dec. 31, 2020	$ 95	$ 61,153	$ (3,915)	$ 200,066	$ (8,691)	$ 248,708
Balance (in shares) at Dec. 31, 2020	9,513,867
Increase (Decrease) in Stockholders' Equity
Net income				17,430		17,430
Other comprehensive loss					3,167	3,167
Cash dividends declared				(9,269)		(9,269)
Share-based compensation		351				351
Share-based compensation (in shares)	20,437
Allocation of ESOP shares		764	490			1,254
Exercise of options for common stock	$ (2)	(5,317)				(5,319)
Exercise of options for common stock (in shares)	(210,244)
Balance at Dec. 31, 2021	$ 93	56,951	(3,425)	208,227	(5,524)	256,322
Balance (in shares) at Dec. 31, 2021	9,324,060
Increase (Decrease) in Stockholders' Equity
Net income				16,156		16,156
Other comprehensive loss					(2,220)	(2,220)
Cash dividends declared				(9,069)		(9,069)
Share-based compensation		480				480
Share-based compensation (in shares)	19,227
Allocation of ESOP shares		602	489			1,091
Exercise of options for common stock	$ (2)	(6,208)				(6,210)
Exercise of options for common stock (in shares)	(272,211)
Balance at Dec. 31, 2022	$ 91	$ 51,825	$ (2,936)	$ 215,314	$ (7,744)	$ 256,550
Balance (in shares) at Dec. 31, 2022	9,071,076

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Consolidated Statements of Stockholders' Equity, Share Data
Cash dividends declared per common share (in dollars per share)	$ 1.02	$ 1.02
Common Stock
Consolidated Statements of Stockholders' Equity, Share Data
Allocation of ESOP shares, shares	48,933	48,933

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 16,156	$ 17,430
Adjustments to reconcile net income to net cash from operating activities:
Reversal of provision for loan losses	(576)	(1,592)
Depreciation and amortization	1,181	1,151
Deferred income tax expense	1,090	305
Amortization of fees, discounts, and premiums, net	(171)	(405)
Amortization of right-of-use asset	2,946	3,071
Origination of loans held for sale	(5,302)	(33,739)
Proceeds from sales of loans held for sale	5,299	36,598
Loss (gain) on sale of loans, net	3	(663)
Gain on sale of investment securities available for sale		(339)
Gain on sale of investment securities held to maturity		(1,501)
Net loss on disposal of premises and equipment		2
Gain on lease modification		(35)
Gain on bank-owned life insurance	(1,138)
ESOP expense	1,091	1,254
Share-based compensation expense	480	351
Net (increase) decrease in accrued interest receivable	(329)	729
Net increase in bank-owned life insurance	(792)	(779)
Net decrease (increase) in prepaid expenses and other assets	289	(4,119)
Net decrease in accounts payable and accrued expenses	1,006	(1,254)
Net decrease in lease liability	(2,911)	(3,060)
Net decrease in advance payments by borrowers for taxes and insurance	(630)	(583)
Net increase in income taxes payable	(1,026)	(298)
Net cash from operating activities	16,666	12,524
Cash flows from investing activities:
Purchases of investment securities held to maturity	(142,336)	(515,769)
Purchases of investment securities available for sale	(24,760)
Principal repayments on investment securities held to maturity	61,009	104,800
Principal repayments on investment securities available for sale	1,279	198
Proceeds from sale of investment securities held to maturity		23,570
Proceeds from sale of investment securities available for sale		3,330
Principal repayments on loans receivable, net of loan originations	8,739	106,264
Purchases of Federal Home Loan Bank stock	(1,304)	(29)
Proceeds from redemption of Federal Home Loan Bank stock	1,280
Purchases of Federal Reserve Bank stock	(13)	(13)
Purchases of bank-owned life insurance		(5,000)
Proceeds from bank-owned life insurance	5,569
Purchases of premises and equipment	(4,715)	(363)
Net cash from investing activities	(95,252)	(283,012)
Cash flows from financing activities:
Net (decrease) increase in deposits	34,324	22,028
Proceeds from advances from the Federal Home Loan Bank	22,000
Repayments of advances from the Federal Home Loan Bank	(22,000)
Repurchases of common stock	(5,973)	(5,000)
Cash dividends paid	(9,071)	(10,224)
Net cash from financing activities	19,280	6,804
Net decrease in cash and cash equivalents	(59,306)	(263,684)
Cash and cash equivalents at beginning of the year	99,859	363,543
Cash and cash equivalents at end of the year	40,553	99,859
Cash paid for:
Interest on deposits and borrowings	6,549	6,276
Income taxes	5,254	6,366
Supplemental disclosure of noncash investing and financing activities:
Company stock repurchased through stock swap and net settlement transactions	236	319
Establishment of right-of-use asset, net of incentives and modifications	7,462	720
Establishment of lease liability, net of modifications	$ 7,462	$ 720

Organization

Organization	12 Months Ended
	Dec. 31, 2022
Organization
Organization	(1) Organization ​ Territorial Bancorp Inc. is a Maryland corporation and is the holding company for Territorial Savings Bank. Territorial Savings Bank is a Hawaii state-chartered bank headquartered in Honolulu, Hawaii and is a member of the Federal Reserve System. Territorial Savings Bank has ​

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2022
Basis of Presentation
Summary of Significant Accounting Policies	(2) Summary of Significant Accounting Policies ​ (a) Description of Business ​ Territorial Bancorp Inc. (the Company), through its wholly-owned subsidiary, Territorial Savings Bank (the Bank), provides loan and deposit products and services primarily to individual customers through 29 branches located throughout Hawaii. We deal primarily in residential mortgage loans in the State of Hawaii. The Company’s earnings depend primarily on its net interest income, which is the difference between the interest income earned on interest-earning assets (loans receivable and investments) and the interest expense incurred on interest-bearing liabilities (deposit liabilities and borrowings). Deposits traditionally have been the principal source of the Bank’s funds for use in lending, meeting liquidity requirements, and making investments. The Company also derives funds from receipt of interest and principal repayments on outstanding loans receivable and investments, borrowings from the Federal Home Loan Bank (FHLB), securities sold under agreements to repurchase, and proceeds from issuance of common stock. ​ (b) Principles of Consolidation ​ The Consolidated Financial Statements include the accounts and results of operations of Territorial Bancorp Inc. and Territorial Savings Bank and its wholly-owned subsidiaries. Significant intercompany balances and transactions have been eliminated in consolidation. ​ (c) Cash and Cash Equivalents ​ Cash and cash equivalents includes cash and due from banks, interest-bearing deposits in other banks, federal funds sold, and short-term, highly liquid investments with original maturities of three months or less. ​ (d) Investment Securities ​ The Company classifies and accounts for its investment securities as follows: (1) held-to-maturity debt securities in which the Company has the positive intent and ability to hold to maturity are reported at amortized cost; (2) trading securities that are purchased for the purpose of selling in the near term are reported at fair value, with unrealized gains and losses included in current earnings; and (3) available-for-sale securities not classified as either held-to-maturity or trading securities are reported at fair value, with unrealized gains and losses excluded from current earnings and reported as a separate component of equity. At December 31, 2022, $20.8 million of securities were classified as available-for-sale and the remaining securites were classified as held-to-maturity. At December 31, 2021, the Company classified all of its investments as held-to-maturity. ​ A decline in the market value of any available-for-sale or held-to-maturity security below cost, that is deemed to be other than temporary, results in an impairment to reduce the carrying amount to fair value. To determine whether impairment is other than temporary, the Company considers the type of the investment, the cause of the decline in value and the amount and duration of the decline in value. It also considers whether it has the intent and ability not to sell and would not be required to sell the security for a sufficient period of time to recover the remaining amortized cost basis. ​ Gains or losses on the sale of investment securities are computed using the specific-identification method. The Company amortizes premiums and accretes discounts associated with investment securities using the interest method over the contractual life of the respective investment security. Such amortization and accretion is included in the interest income line item in the Consolidated Statements of Income. Interest income is recognized when earned. ​ (e) Loans Receivable ​ This policy applies to all loan classes. Loans receivable are stated at the principal amount outstanding, less the allowance for loan losses, loan origination fees and costs, and commitment fees. Interest on loans receivable is accrued as earned. The Company has a policy of placing loans on a nonaccrual basis when 90 days or more contractually delinquent or when, in the opinion of management, collection of all or part of the principal balance appears doubtful. For nonaccrual loans, the Company records payments received as a reduction in principal. The Company, considering current information and events regarding the borrowers’ ability to repay their obligations, considers a loan to be impaired when it is probable that the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. When a loan is considered to be impaired, the amount of the impairment is measured based on the present value of expected future cash flows discounted at the loan’s effective interest rate or, if the loan is considered to be collateral dependent, based on the fair value of the collateral less estimated costs to sell. Impairment losses are written off against the allowance for loan losses. For nonaccrual impaired loans, the Company records payments received as a reduction in principal. A nonaccrual loan may be restored to an accrual basis when principal and interest payments are current and full payment of principal and interest is expected. ​ (f) Loans Held for Sale ​ Loans held for sale are stated at the lower of aggregate cost or market value. Net fees and costs of originating loans held for sale are deferred and are included in the basis for determining the gain or loss on sales of loans held for sale. ​ (g) Deferred Loan Origination Fees and Unearned Loan Discounts ​ Loan origination and commitment fees and certain direct loan origination costs are being deferred, and the net amount is recognized over the life of the related loan as an adjustment to yield. Net deferred loan fees are amortized using the interest method over the contractual term of the loan, adjusted for actual prepayments. Net unamortized fees on loans paid in full are recognized as a component of interest income. ​ (h) Real Estate Owned ​ Real estate owned is valued at the time of foreclosure at fair value, less estimated cost to sell, thereby establishing a new cost basis. The Company obtains appraisals based on recent comparable sales to assist management in estimating the fair value of real estate owned. Subsequent to acquisition, real estate owned is valued at the lower of cost or fair value, less estimated cost to sell. Declines in value are charged to expense through a direct write-down of the asset. Costs related to holding real estate are charged to expense while costs related to development and improvements are capitalized. Net gains or losses recognized on the sale of real estate owned are included in other general and administrative expenses. ​ (i) Allowance for Loan Losses ​ The Company maintains an allowance adequate to cover management’s estimate of probable loan losses as of the balance sheet date. The Company’s allowance for loan losses is maintained at a level considered adequate to provide for losses that can be estimated based upon specific and general conditions. All loan losses are charged, and all recoveries are credited, to the allowance for loan losses. Additions to the allowance for loan losses are provided by charges to income based on various factors, which, in the Company’s judgment, deserve current recognition in estimating probable losses. Charge-offs to the allowance are made when management determines that collectability of all or a portion of a loan is doubtful and available collateral is insufficient to repay the loan. ​ General allowances are established for loan losses on a portfolio basis for loans that do not meet the definition of impaired, in accordance with the Receivables topic of the FASB ASC. The portfolio is grouped into similar risk characteristics, primarily loan type and loan-to-value ratio. The Company applies an estimated loss rate to each loan group. The loss rates applied are based upon its loss experience adjusted, as appropriate, for qualitative and environmental factors discussed below. This evaluation is inherently subjective, as it requires material estimates that may be susceptible to significant revisions based upon changes in economic and real estate market conditions. Actual loan losses may be significantly more than the allowance for loan losses the Company has established, which could have a material negative effect on its financial results. ​ Residential mortgage loans represent the largest segment of the Company’s loan portfolio. Residential mortgage loans are secured by a first mortgage on residential real estate in Hawaii and consist primarily of fixed-rate mortgage loans which have been underwritten to Freddie Mac and Fannie Mae guidelines and have similar risk characteristics. The loan loss allowance is determined by first calculating the historical loss rate for this segment of the portfolio. The loss rate may be adjusted for qualitative and environmental factors. The allowance for loan loss is calculated by multiplying the adjusted loss rate by the total loans in this segment of the portfolio. ​ The adjustments to historical loss experience are based on an evaluation of several qualitative and environmental factors, including: ​ ● changes in lending policies and procedures, including changes in underwriting standards and collections, charge-off and recovery practices; ​ ● changes in international, national, regional and local economic business conditions and developments that affect the collectibility of the portfolio; ​ ● changes in the bank’s internal loan review system; ​ ● changes in the experience, depth and ability of personnel in the mortgage loan origination and loan servicing departments; ​ ● changes in the volume and severity of past due loans, the volume of nonaccrual loans and classified assets; ​ ● changes in the nature and volume of loans being originated; ​ ● changes in the value of underlying collateral for collateral dependent loans; ​ ● existence and any changes in concentrations of credit; ​ ● external factors such as competition, legal and regulatory requirements on the level of estimated credit losses in the existing loan portfolio; and ​ ● changes in the amount of loans with payment deferrals. ​ The Company also uses historical loss rates adjusted for qualitative and environmental factors to establish loan loss allowances for the following portfolio segments: ​ ● home equity loans and lines of credit; and ​ ● consumer and other loans. ​ The Company has a limited loss experience for the construction, commercial and other mortgage segment of the loan portfolio. The loan loss allowance on this portfolio segment is determined using the loan loss rate of other financial institutions in the State of Hawaii. The allowance for loan loss is calculated by multiplying the loan loss rate of other financial institutions in the state by the total loans in this segment of the Company’s loan portfolio. ​ The allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. In addition, the unallocated allowance is established to provide for probable losses that have been incurred as of the reporting date but are not reflected in the allocated allowance. ​ While the Company uses the best information available to make evaluations, future adjustments to the allowance may be necessary if conditions differ substantially from the information used in making the evaluations. In addition, as an integral part of their examination process, the bank regulators will periodically review the allowance for loan losses. The bank regulators may require the Company to increase the allowance based on their analysis of information available at the time of their examination. ​ (j) Transfer of Financial Assets ​ Transfers of financial assets are accounted for as sales when control is surrendered. Control is surrendered when the assets have been isolated from the Company, the transferee obtains the right to pledge or exchange the assets without constraint, and the Company does not maintain effective control over the transferred assets. Mortgage loans sold for cash are accounted for as sales as the above criteria have been met. ​ Mortgage loans may also be packaged into securities that are issued and guaranteed by U.S. government-sponsored enterprises or a U.S. government agency. The Company receives of the mortgage-backed securities issued. The mortgage-backed securities received in securitizations are valued at fair value and classified as held-to-maturity. A gain or loss in the securitization transactions is recognized for the difference between the fair value of the mortgage-backed securities received and the amortized cost of the loans securitized. ​ Mortgage loan transfers accounted for as sales and securitizations are without recourse, except for normal representations and warranties provided in sales transactions, and the Company may retain the related rights to service the loans. The retained servicing rights create mortgage servicing assets that are accounted for in accordance with the Transfers and Servicing topic of the FASB ASC. Mortgage servicing assets are initially valued at fair value and subsequently at the lower of cost or fair value and are amortized in proportion to and over the period of estimated net servicing income. The Company uses a discounted cash flow model to determine the fair value of retained mortgage servicing rights. The amount of mortgage servicing rights is immaterial to the financial statement. ​ (k) Premises and Equipment ​ Premises and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is principally computed on the straight-line method over the estimated useful lives of the respective assets. The estimated useful life of buildings and improvements is . Leasehold improvements are amortized on a straight-line basis over the shorter of the lease term or estimated useful life of the asset. ​ (l) Income Taxes ​ The Company files consolidated federal income tax and consolidated state franchise tax returns. ​ Deferred tax assets and liabilities are recognized using the asset and liability method of accounting for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and net operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. ​ We establish income tax contingency reserves for potential tax liabilities related to uncertain tax positions. A liability for income tax uncertainties would be recorded for unrecognized tax benefits related to uncertain tax positions where it is more likely than not that the position will be sustained upon examination by a taxing authority. ​ As of December 31, 2022 and 2021, the Company had not recognized a liability for income tax uncertainties in the accompanying Consolidated Balance Sheets because management concluded that the Company does not have uncertain tax positions. ​ The Company recognizes interest and penalties related to tax liabilities in other interest expense and other general and administrative expenses, respectively, in the Consolidated Statements of Income. ​ Tax years 2019 to 2021 currently remain subject to examination by the Internal Revenue Service and by the Department of Taxation of the State of Hawaii. ​ (m) Impairment of Long-Lived Assets ​ Long-lived assets, such as premises and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of would be separately presented in the Consolidated Balance Sheets and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated. ​ (n) Pension Plan ​ Pension benefit costs (returns) are charged (credited) to salaries and employee benefits expense or other income, and the corresponding prepaid (accrued) pension cost is recorded in prepaid expenses and other assets or accounts payable and accrued expenses in the Consolidated Balance Sheets. The Company’s policy is to fund pension costs in amounts that will not be less than the minimum funding requirements of the Employee Retirement Income Security Act of 1974 and will not exceed the maximum tax-deductible amounts. The Company generally funds at least the net periodic pension cost, subject to limits and targeted funded status as determined with the consulting actuary. ​ (o) Share-Based Compensation ​ The Company grants share-based compensation awards, including restricted stock and restricted stock units, which are either performance-based or time-based. The fair value of the restricted stock and restricted stock unit awards were based on the closing price of the Company’s stock on the date of grant. The cost of these awards are amortized in the Consolidated Statements of Income on a straight-line basis over the vesting period. The amount of performance-based restricted stock units that vest on a performance condition is remeasured quarterly based on how the Company’s return on average equity compares to the SNL Bank Index. The fair value of performance-based restricted stock units that are based on how the Company’s total stock return compares to the SNL Bank Index was measured using a Monte-Carlo valuation. ​ (p) Supplemental Employee Retirement Plan (SERP) ​ The SERP is a noncontributory supplemental retirement plan covering certain current and former employees of the Company. Benefits in the SERP plan are paid after retirement, in addition to the benefits provided by the Pension Plan. The Company accrues SERP costs over the estimated period until retirement by charging salaries and employee benefits expense in the Consolidated Statements of Income, with a corresponding credit to accounts payable and accrued expenses in the Consolidated Balance Sheets. ​ (q) Employee Stock Ownership Plan (ESOP) ​ The cost of shares issued to the ESOP, but not yet allocated to participants, is shown as a reduction of stockholders’ equity. Compensation expense is based on the market price of shares as they are committed to be released to participant accounts. Dividends on allocated ESOP shares reduce retained earnings; dividends on unearned ESOP shares reduce debt and accrued interest. ​ (r) Earnings Per Share ​ We have two forms of our outstanding common stock: common stock and unvested restricted stock awards. Holders of unvested restricted stock awards receive dividends at the same rate as common shareholders and they both share equally in undistributed earnings. Unvested restricted stock awards that are time-based contain nonforfeitable rights to dividends or dividend equivalents are considered to be participating securities in the earnings per share computation using the two-class method. Under the two-class method, earnings are allocated to common shareholders and participating securities according to their respective rights to earnings. Unvested restricted stock awards that vest based on performance or market conditions are not considered to be participating securities in the earnings per share calculation because accrued dividends on shares that do not vest are forfeited. ​ Basic earnings per share is computed by dividing net income allocated to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income allocated to common shareholders by the sum of the weighted-average number of shares outstanding plus the dilutive effect of stock options and restricted stock. ESOP shares not committed to be released are not considered outstanding. ​ (s) Common Stock Repurchase Program ​ The Company adopted common stock repurchase programs in which shares repurchased reduce the amount of shares issued and outstanding. The repurchased shares may be reissued in connection with share-based compensation plans and for general corporate purposes. During 2022 and 2021, the Company repurchased per share, respectively, as part of the repurchase programs authorized by the Board of Directors. ​ (t) Bank-Owned Life Insurance ​ The Company’s investment in bank-owned life insurance is based on cash surrender value. The Company invests in bank-owned life insurance to provide a funding source for benefit plan obligations. Bank-owned life insurance also generally provides noninterest income that is nontaxable. Federal regulations generally limit the investment in bank-owned life insurance to of the Bank’s Tier 1 capital plus the allowance for loan losses. At December 31, 2022, this limit was ​ (u) Leases ​ The Company records a right-of-use (ROU) asset for those leases that convey rights to control use of identified assets for a period of time in exchange for consideration. The Company is also required to record a lease liability for the present value of future payment commitments. The Company leases most of its premises and some vehicles and equipment under operating leases expiring on various dates through 2037. The majority of lease agreements relate to real estate and generally provide that the Company pay taxes, insurance, maintenance and certain other variable operating expenses applicable to the leased premises. Variable lease components and nonlease components are not included in the Company’s computation of the ROU asset or lease liability. The Company also does not include short-term leases in the computation of the ROU asset or lease liability. Short-term leases are leases with a term at commencement of 12 months or less. Short-term lease expense is recorded on a straight-line basis over the term of the lease. Lease agreements do not contain any residual value guarantees or restrictive covenants. ​ The value of the ROU asset and lease liability is impacted by the amount of the periodic payment required, length of the lease term, lease incentives and the discount rate used to calculate the present value of the minimum lease payments. Certain leases have renewal options at the expiration of the lease terms. Generally, option periods are not included in the computation of the lease term, ROU asset or lease liability because the Company is not reasonably certain to exercise renewal options at the expiration of the lease terms. Because the discount rates implicit in our leases are not known, discount rates have been estimated using the rates for fixed-rate, amortizing advances from the FHLB for the approximate terms of the leases. ​ (v) Use of Estimates ​ The preparation of the Consolidated Financial Statements requires management to make a number of estimates and assumptions relating to the reported amount of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amount of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include the allowance for loan losses; valuation of certain investment securities and determination as to whether declines in fair value below amortized cost are other than temporary; valuation allowances for deferred income tax assets; mortgage servicing assets; and assets and obligations related to employee benefit plans. Accordingly, actual results could differ from those estimates. ​ (w) Recently Issued Accounting Pronouncements ​ In June 2016, the Financial Accounting Standards Board (FASB) issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The ASU changes the threshold for recognizing losses from a “probable” to an “expected” model. The new model is referred to as the current expected credit loss model and applies to loans, leases, held-to-maturity investments and loan commitments. The amendment requires the measurement of all expected credit losses for financial assets as of the reporting date (including historical experience, current conditions and reasonable and supportable forecasts) and enhanced disclosures that will help financial statement users understand the estimates and judgments used in estimating credit losses and evaluating the credit quality of an organization’s portfolio. The amendment is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. In November 2019, the FASB issued an update that delayed the effective date of the amendment for smaller reporting companies, as defined by the Securities and Exchange Commission, to fiscal years beginning after December 15, 2022. The Company is a smaller reporting company. The Company has formed a team that is working on an implementation plan to adopt the amendment. The Company is also working with a consultant to measure expected losses required by the amendment. The Company is finalizing its adoption of the current expected credit loss standard by developing new policies, procedures, internal controls and disclosures which will be used when the standard is adopted. Based on the current composition of the Company’s loan portfolio as of December 31, 2022, and the current expectation of future economic conditions, the allowance for credit losses is expected to increase by million at the January 1, 2023 adoption date. The allowance for credit losses is expected to increase because the new standard measures credit losses over the expected life of the loans in the Company’s loan portfolio. Most of the loans in the Company’s loan portfolio are 30-year mortgage loans which have a long average life. All of the Company's investments in mortgage-backed securities and collateralized mortgage obligations have been issued by Freddie Mac or Fannie Mae, which are U.S. government-sponsored enterprises, or Ginnie Mae, which is a U.S. government agency. These agencies and enterprises guarantee the payment of principal and interest and therefore the Company will not record an allowance on its held-to-maturity or available-for-sale securities. The adoption of the current expected credit loss standard will be recorded by making an after-tax adjustment to retained earnings. Although the adjustment for the adoption of the current expected credit loss standard will reduce retained earnings, the Company will continue to be well-capitalized. ​ In March 2022, the FASB issued ASU 2022-02, Financial Instruments-Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures. The ASU eliminates the accounting guidance for loans modified as troubled debt restructurings by creditors while enhancing disclosure requirements for certain loan refinancings and restructurings by creditors when a borrower is experiencing financial difficulty. Additionally, the ASU requires public business entities to disclose current-period gross write-offs by year of origination for financing receivables and net investments in leases. This ASU will be effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years, upon the Company’s adoption of the amendments in ASU 2016-13. The Company is currently evaluating the effects that ASU 2022-03 will have on its consolidated financial statements. ​ In June 2022, the FASB issued ASU 2022-03, Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions to clarify that contractual sale restrictions should not be considered in the measurement of the fair value of an equity security. The Company owns stock in the Federal Reserve Bank (FRB) and in the FHLB which is valued at historical cost which approximates fair value. Ownership of stock is a condition for services the Company receives from the FRB and FHLB. The stock is not publically traded and can only be issued, exchanged, redeemed or repurchased by the FRB and the FHLB. ASU 2022-03 is effective for fiscal years beginning after December 15, 2023. The Company does not expect the adoption of this ASU to have a material effect on its consolidated financial statements. ​

Cash and Cash Equivalents

Cash and Cash Equivalents	12 Months Ended
	Dec. 31, 2022
Cash and Cash Equivalents
Cash and Cash Equivalents	(3) Cash and Cash Equivalents ​ The table below presents the balances of cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Cash and due from banks ​ $ 9,722 ​ $ 11,662 ​ Interest-earning deposits in other banks ​ 30,831 ​ 88,197 ​ Cash and cash equivalents ​ $ 40,553 ​ $ 99,859 ​ ​ Interest-earning deposits in other banks consist primarily of deposits at the Federal Reserve Bank of San Francisco.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2022
Investment Securities.
Investment Securities	(4) Investment Securities ​ The amortized cost and fair values of investment securities are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross Unrealized ​ Estimated (Dollars in thousands) Cost Gains Losses Fair Value December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ 23,544 ​ $ — $ (2,723) ​ $ 20,821 ​ Total ​ $ 23,544 ​ $ — $ (2,723) ​ $ 20,821 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ $ 717,773 ​ $ 62 $ (126,751) ​ $ 591,084 ​ Total ​ $ 717,773 ​ $ 62 $ (126,751) ​ $ 591,084 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ $ 636,442 ​ $ 5,699 $ (7,154) ​ $ 634,987 ​ Total ​ $ 636,442 ​ $ 5,699 $ (7,154) ​ $ 634,987 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized Estimated (Dollars in thousands) Cost Fair Value Available-for-sale: ​ ​ ​ ​ ​ ​ ​ Due after 10 years ​ $ 23,544 ​ $ 20,821 ​ Total ​ $ 23,544 ​ $ 20,821 ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ Due within 5 years ​ $ 19 ​ $ 18 ​ Due after 5 years through 10 years ​ 12 ​ 12 ​ Due after 10 years ​ 717,742 ​ 591,054 ​ Total ​ $ 717,773 ​ $ 591,084 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Proceeds from sales ​ $ — ​ $ 26,900 Gross gains ​ — ​ 1,840 Gross losses ​ — ​ — ​ The Company did not sell any held-to-maturity mortgage-backed securities during 2022. During 2021, the Company sold million. ​ The Company did not sell any available-for-sale mortgage-backed securities during 2022. During 2021, the Company sold ​ Investment securities ​ Provided below is a summary of investment securities which were in an unrealized loss position at December 31, 2022 and 2021. The Company does not intend to sell securities until such time as the value recovers or the securities mature and it is not more likely than not that the Company will be required to sell the securities prior to recovery of value or the securities mature. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less Than 12 Months 12 Months or Longer Total Unrealized Unrealized Number of Unrealized Description of securities Fair Value Losses Fair Value Losses Securities Fair Value Losses (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enteprises ​ $ 20,821 ​ $ (2,723) ​ $ — ​ $ — 4 ​ $ 20,821 ​ $ (2,723) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ $ 210,128 ​ $ (22,209) ​ $ 377,418 ​ $ (104,542) 148 ​ $ 587,546 ​ $ (126,751) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ $ 482,629 ​ $ (6,976) ​ $ 3,681 ​ $ (178) 43 ​ $ 486,310 ​ $ (7,154) ​ ​ Mortgage-Backed Securities. The unrealized losses on the Company’s investment in mortgage-backed securities were caused by increases in market interest rates subsequent to purchase. All of the mortgage-backed securities are guaranteed by Freddie Mac or Fannie Mae, which are U.S. government-sponsored enterprises, or Ginnie Mae, which is a U.S. government agency. Since the decline in market value is attributable to changes in interest rates and not credit quality, and the Company does not intend to sell these investments until maturity and it is not more likely than not that the Company will be required to sell such investments prior to recovery of its cost basis, the Company does not consider these investments to be other-than-temporarily impaired as of December 31, 2022 and 2021.

Federal Home Loan Bank Stock

Federal Home Loan Bank Stock	12 Months Ended
	Dec. 31, 2022
FHLB stock
Federal Home Loan Bank Stock
Federal Home Loan Bank Stock	(5) Federal Home Loan Bank Stock ​ The Bank, as a member of the FHLB system, is required to obtain and hold shares of capital stock in the FHLB. At December 31, 2022 and 2021, the Bank met such requirement. At December 31, 2022 and 2021, the Bank owned ​ The Company evaluated its investment in the stock of the FHLB Des Moines for impairment. Based on the Company’s evaluation of the underlying investment, including the long-term nature of the investment and the liquidity position of the FHLB Des Moines, the Company did not consider its FHLB stock other-than-temporarily impaired. There were no observable, orderly transactions at a price that would require the Company to update the value of the stock of the FHLB Des Moines. ​

Federal Reserve Bank Stock

Federal Reserve Bank Stock	12 Months Ended
	Dec. 31, 2021
FRB stock
Federal Reserve Bank Stock
Federal Reserve Bank Stock	(6) Federal Reserve Bank Stock ​ The Bank, as a member of the Federal Reserve System, is required to hold shares of capital stock of the FRB of San Francisco equal to six percent of capital and surplus of the Bank. At December 31, 2022 and 2021, the Bank met such requirement. At December 31, 2022 and 2021, the Bank owned ​ The Company evaluated its investment in the stock of the FRB of San Francisco for impairment. Based on the Company’s evaluation of the underlying investment, including the long-term nature of the investment and the liquidity position of the FRB of San Francisco, the Company did not consider its FRB stock other-than-temporarily impaired. There were no observable, orderly transactions at a price that would require the Company to update the value of the stock of the FRB of San Francisco. ​

Loans Receivable and Allowance

Loans Receivable and Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2022
Loans Receivable and Allowance for Loan Losses
Loans Receivable and Allowance for Loan Losses	(7) Loans Receivable and Allowance for Loan Losses ​ The components of loans receivable are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2022 2021 ​ Real estate loans: ​ ​ ​ ​ ​ ​ ​ First mortgages: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential ​ $ 1,253,558 ​ $ 1,267,537 ​ Multi-family residential ​ 6,448 ​ 5,468 ​ Construction, commercial and other ​ 23,903 ​ 18,590 ​ Home equity loans and lines of credit ​ 6,426 ​ 7,121 ​ Total real estate loans ​ 1,290,335 ​ 1,298,716 ​ Other loans: ​ ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ 216 ​ 278 ​ Consumer and other loans ​ 8,381 ​ 8,192 ​ Total other loans ​ 8,597 ​ 8,470 ​ Less: ​ ​ ​ ​ ​ ​ ​ Net unearned fees and discounts ​ (2,136) ​ (1,693) ​ Allowance for loan losses ​ (2,032) ​ (2,669) ​ Total unearned fees, discounts and allowance for loan losses ​ (4,168) ​ (4,362) ​ Loans receivable, net ​ $ 1,294,764 ​ $ 1,302,824 ​ ​ The table below presents the activity in the allowance for loan losses by portfolio segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals Year ended December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of year ​ $ 1,814 ​ $ 435 ​ $ 1 ​ $ 89 ​ $ 330 ​ $ 2,669 ​ (Reversal of provision) provision for loan losses ​ (551) ​ (1) ​ — ​ 47 ​ (71) ​ (576) ​ ​ ​ 1,263 ​ 434 ​ 1 ​ 136 ​ 259 ​ 2,093 ​ Charge-offs ​ — ​ — ​ — ​ (62) ​ — ​ (62) ​ Recoveries ​ — ​ — ​ — ​ 1 ​ — ​ 1 ​ Net charge-offs ​ — ​ — ​ — ​ (61) ​ — ​ (61) ​ Balance, end of year ​ $ 1,263 ​ $ 434 ​ $ 1 ​ $ 75 ​ $ 259 ​ $ 2,032 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of year ​ $ 3,102 ​ $ 406 ​ $ 1 ​ $ 146 ​ $ 607 ​ $ 4,262 ​ (Reversal of provision) provision for loan losses ​ (1,305) ​ 29 ​ — ​ (39) ​ (277) ​ (1,592) ​ ​ ​ 1,797 ​ 435 ​ 1 ​ 107 ​ 330 ​ 2,670 ​ Charge-offs ​ — ​ — ​ — ​ (22) ​ — ​ (22) ​ Recoveries ​ 17 ​ — ​ — ​ 4 ​ — ​ 21 ​ Net recoveries (charge-offs) ​ 17 ​ — ​ — ​ (18) ​ — ​ (1) ​ Balance, end of year ​ $ 1,814 ​ $ 435 ​ $ 1 ​ $ 89 ​ $ 330 ​ $ 2,669 ​ ​ The allowance for loan loss for each segment of the loan portfolio is generally determined by calculating the historical loss of each segment in a seven-year look-back period and adding a qualitative adjustment, when appropriate, for the following factors: ​ ● changes in lending policies and procedures, including changes in underwriting standards and collections, charge-off and recovery practices; ● changes in international, national, regional and local economic business conditions and developments that affect the collectability of the portfolio; ● changes in the bank’s internal loan review system; ● changes in the experience, depth and ability of personnel in the mortgage loan origination and loan servicing departments; ● changes in the volume and severity of past due loans, the volume of nonaccrual loans and classified assets; ● changes in the nature and volume of loans being originated; ● changes in the value of underlying collateral for collateral dependent loans; ● existence and any changes in concentrations of credit; ● external factors such as competition, legal and regulatory requirements on the level of estimated credit losses in the existing loan portfolio; and ​ ● changes in the amount of loans with payment deferrals. ​ The Company has granted loan payment deferrals to borrowers who have been affected by the COVID-19 pandemic. Additional loan loss provisions were established because of these loan payment deferrals and the higher unemployment rate that occurred because of the COVID-19 pandemic. ​ The allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. The unallocated allowance is established for probable losses that have been incurred as of the reporting date but are not reflected in the allocated allowance. ​ Management considers the allowance for loan losses at December 31, 2022 to be at an appropriate level to provide for probable losses that can be reasonably estimated based on general and specific conditions at that date. While the Company uses the best information it has available to make evaluations, future adjustments to the allowance may be necessary if conditions differ substantially from the information used in making the evaluations. To the extent actual outcomes differ from the estimates, additional provisions for credit losses may be required that would reduce future earnings. ​ The table below presents the balance in the allowance for loan losses and the recorded investment in loans, net of unearned fees and discounts, by portfolio segment and based on impairment method: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 1,263 ​ 434 ​ 1 ​ 75 ​ 259 ​ 2,032 ​ Total ending allowance balance ​ $ 1,263 ​ $ 434 ​ $ 1 ​ $ 75 ​ $ 259 ​ $ 2,032 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 2,693 ​ $ — ​ $ 16 ​ $ — ​ $ 6 ​ $ 2,715 ​ Collectively evaluated for impairment ​ 1,255,300 ​ 23,775 ​ ​ 6,411 ​ 8,595 ​ — ​ 1,294,081 ​ Total ending loan balance ​ $ 1,257,993 ​ $ 23,775 ​ $ 6,427 ​ $ 8,595 ​ $ 6 ​ $ 1,296,796 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 1,814 ​ 435 ​ 1 ​ 89 ​ 330 ​ 2,669 ​ Total ending allowance balance ​ $ 1,814 ​ $ 435 ​ $ 1 ​ $ 89 ​ $ 330 ​ $ 2,669 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 3,812 ​ $ — ​ $ 19 ​ $ — ​ $ — ​ $ 3,831 ​ Collectively evaluated for impairment ​ 1,267,560 ​ 18,529 ​ 7,103 ​ 8,470 ​ — ​ 1,301,662 ​ Total ending loan balance ​ $ 1,271,372 ​ $ 18,529 ​ $ 7,122 ​ $ 8,470 ​ $ — ​ $ 1,305,493 ​ ​ The table below presents the balance of impaired loans individually evaluated for impairment by class of loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid Recorded Principal (Dollars in thousands) Investment Balance December 31, 2022: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,693 ​ $ 3,209 ​ Home equity loans and lines of credit ​ 16 ​ 30 ​ Consumer loans ​ 6 ​ 6 ​ Total ​ $ 2,715 ​ $ 3,245 ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 3,812 ​ $ 4,299 ​ Home equity loans and lines of credit ​ ​ 19 ​ 31 ​ Total ​ $ 3,831 ​ $ 4,330 ​ ​ ​ The table below presents the average recorded investment and interest income recognized on impaired loans by class of loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ Average Recorded Interest Income (Dollars in thousands) Investment Recognized 2022: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,776 ​ $ 24 ​ Home equity loans and lines of credit ​ 17 ​ — ​ Consumer loans ​ 6 ​ ​ — ​ Total ​ $ 2,799 ​ $ 24 ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 3,888 ​ $ 36 ​ Home equity loans and lines of credit ​ 21 ​ — ​ Total ​ $ 3,909 ​ $ 36 ​ ​ There were no loans individually evaluated for impairment with a related allowance for loan loss as of December 31, 2022 or 2021. Loans individually evaluated for impairment do not have an allocated allowance for loan loss because they are written down to fair value at the time of impairment. An impaired loan would also not have an allocated allowance if the value of the property securing the loan, less the cost to sell the property, is greater than the loan balance. ​ The table below presents the aging of loans and accrual status by class of loans, net of unearned fees and discounts. Loans with a formal loan payment deferral plan in place are not considered contractually past due or delinquent if the borrower is in compliance with the loan payment deferral plan: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans 90 Days or More 30 - 59 60 - 89 90 Days or Past Due Days Past Days Past More Total Past Loans Not Total Nonaccrual and Still (Dollars in thousands) Due Due Past Due Due Past Due Loans Loans Accruing December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ 409 ​ $ 559 ​ $ 968 ​ $ 1,250,586 ​ $ 1,251,554 ​ $ 2,279 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 6,439 ​ 6,439 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 23,775 ​ 23,775 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 6,427 ​ 6,427 ​ 16 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 217 ​ 217 ​ — ​ — ​ Consumer and other ​ 6 ​ — ​ 6 ​ 12 ​ 8,372 ​ 8,384 ​ 6 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 6 ​ $ 409 ​ $ 565 ​ $ 980 ​ $ 1,295,816 ​ $ 1,296,796 ​ $ 2,301 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 129 ​ $ — ​ $ 244 ​ $ 373 ​ $ 1,265,540 ​ $ 1,265,913 ​ $ 3,261 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 5,459 ​ 5,459 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 18,529 ​ 18,529 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 7,122 ​ 7,122 ​ 19 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 278 ​ 278 ​ — ​ — ​ Consumer and other ​ 3 ​ — ​ 24 ​ 27 ​ 8,165 ​ 8,192 ​ — ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 132 ​ $ — ​ $ 268 ​ $ 400 ​ $ 1,305,093 ​ $ 1,305,493 ​ $ 3,280 ​ $ 24 ​ ​ The Company primarily uses the aging of loans and accrual status to monitor the credit quality of its loan portfolio. When a mortgage loan becomes seriously delinquent ( or more contractually past due), it displays weaknesses that may result in a loss. As a loan becomes more delinquent, the likelihood of the borrower repaying the loan decreases and the loan becomes more collateral-dependent. A mortgage loan becomes collateral-dependent when the proceeds for repayment can be expected to come only from the sale or operation of the collateral and not from borrower repayments. Generally, appraisals are obtained after a loan becomes collateral-dependent or is delinquent. The carrying value of collateral-dependent loans is adjusted to the fair value of the collateral less selling costs. Any commercial real estate, commercial, construction or equity loan that has a loan balance in excess of a specified amount is also periodically reviewed to determine whether the loan exhibits any weaknesses and is performing in accordance with its contractual terms. ​ The Company had 15 nonaccrual loans with a book value of $2.3 million at December 31, 2022 and 10 nonaccrual loans with a book value of $3.3 million as of December 31, 2021. The Company did not have any loans 90 days or more past due and still accruing interest as of December 31, 2022. The Company had ​ There were no loans modified in a troubled debt restructuring during the year ended December 31, 2022 or 2021. There were no new troubled debt restructurings during the 12 months ended December 31, 2022 that subsequently defaulted. Loan modifications under the CARES Act and the Interagency Statements issued by bank regulators in 2020 are discussed below. ​ The table below summarizes troubled debt restucturings outstanding by class of loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of Accrual Number of Nonaccrual ​ (Dollars in thousands) Loans Status Loans Status Total December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 2 ​ $ 414 ​ ​ 2 ​ $ 410 ​ $ 824 Total ​ 2 ​ $ 414 ​ ​ 2 ​ $ 410 ​ $ 824 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 3 ​ $ 551 ​ ​ 1 ​ $ 340 ​ $ 891 Total ​ 3 ​ $ 551 ​ ​ 1 ​ $ 340 ​ $ 891 ​ There were no delinquent troubled debt restructurings at December 31, 2022. There was that was 59 days delinquent at December 31, 2021. Restructurings include deferrals of interest and/or principal payments and temporary or permanent reductions in interest rates due to the financial difficulties of the borrowers. At December 31, 2022, the Company has ​ The CARES Act provided relief to financial institutions from categorizing eligible loan modifications as troubled debt restructurings over the remaining life of the modified loan. Eligible loan modifications under the CARES Act were required to be related to the COVID-19 pandemic and the borrower’s payments must not have been more than 30 days past due as of December 31, 2019. Loan modifications under the CARES Act must have been executed during the period from March 1, 2020 to January 1, 2022. Banking regulators issued similar guidance, which also clarified that a COVID-19 related loan modification should not be considered a troubled debt restructuring if the borrower was not more than 30 days past due on payments at the time the loan modification program was implemented and the modification is considered short-term (not to exceed six months). The Company uses the provisions of the CARES Act and the Interagency Statements to account for the eligible loans that received modifications. ​ The Company has granted loan payment deferrals to borrowers who have been affected by the COVID-19 pandemic. The table below summarizes loans in the loan payment deferral program by class of loan for which deferred payment amounts continue to remain outstanding: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ ​ ​ December 31, 2021 ​ (Dollars in thousands) ​ Loans in the Loan Payment Deferral Program ​ Percent of Total Loans ​ Loans in the Loan Payment Deferral Program ​ Percent of Total Loans One- to four-family residential mortgage ​ $ 59,948 ​ 4.6 % ​ $ 74,704 ​ 5.7 % Non-residential mortgage ​ ​ 3,220 ​ 0.3 ​ ​ ​ 3,928 ​ 0.3 ​ Total ​ $ 63,168 ​ 4.9 % ​ $ 78,632 ​ 6.0 % ​ The loans on which the Company has granted loan payment deferrals are included in the ALLL calculation. However, loans performing under a loan payment deferral agreement are not considered contractually past due and are excluded from the past due statistics above. ​ The ratio of the current loan balance to the current tax-assessed value of the property securing the mortgage loans in the payment deferral program averaged 49.4% at December 31, 2022. At December 31, 2022, one- to four-family residential mortgage loans represented . All of the Company’s residential mortgage loans are secured by real estate in Hawaii. ​ As of December 31, 2022, there were $63.2 million of loans in the loan payment deferral program, of which $63.0 million had resumed regular payments and a $145,000 one-to four-family mortgage loan was over 150 days delinquent. ​ Since the beginning of 2023, there has not been a material increase in loan delinquencies, significant changes in deposits or significant drawdowns on any lines of credit. We do not have any commercial loans to hotels, businesses in the transportation industry, restaurants or retail establishments. ​ The Company had no real estate owned as of December 31, 2022 or 2021. There were in the process of foreclosure at December 31, 2022. There were ​ Nearly all the Company’s real estate loans are collateralized by real estate located in the State of Hawaii. Loan-to-value ratios on these real estate loans generally do not exceed ​ During the years ended December 31, 2022 and 2021, the Company sold mortgage loans held for sale with principal balances of $5.4 million and $36.2 million, respectively, and recognized a loss of $3,000 and a gain of $663,000 , respectively. The Company had ​ The Company serviced loans for others with principal balances of $36.0 million and $41.3 million at December 31, 2022 and 2021, respectively. Of these amounts, million of loan balances relate to securitizations for which the Company continues to hold the related mortgage-backed securities at December 31, 2022 and 2021, respectively. The amount of contractually specified servicing fees for 2022 and 2021, respectively. The fees are reported in service and other fees in the Consolidated Statements of Income. ​ In the normal course of business, the Company has made loans to certain directors and executive officers under terms which management believes are consistent with the Company’s general lending policies. Loans to directors and executive officers amounted to

Accrued Interest Receivable

Accrued Interest Receivable	12 Months Ended
	Dec. 31, 2022
Accrued Interest Receivable
Accrued Interest Receivable	(8) Accrued Interest Receivable ​ The components of accrued interest receivable are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Loans receivable ​ $ 4,595 ​ $ 4,644 ​ Investment securities ​ ​ 1,497 ​ ​ 1,126 ​ Interest-bearing deposits ​ 23 ​ 16 ​ Total ​ $ 6,115 ​ $ 5,786 ​ ​

Interest Rate Lock and Forward

Interest Rate Lock and Forward Loan Sale Commitments	12 Months Ended
	Dec. 31, 2022
Interest Rate Lock and Forward Loan Sale Commitments
Interest Rate Lock and Forward Loan Sale Commitments	(9) Interest Rate Lock and Forward Loan Sale Commitments ​ The Company may enter into interest rate lock commitments with borrowers on loans intended to be sold. To manage interest rate risk on the lock commitments, the Company may also enter into forward loan sale commitments. The interest rate lock commitments and forward loan sale commitments are treated as derivatives and are recorded at their fair values in prepaid expenses and other assets or in accounts payable and accrued expenses. Changes in fair value are recorded in current earnings. At December 31, 2022, the Company did not have any loans available for sale. ​ The table below presents the location of assets and liabilities related to derivatives: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asset Derivatives ​ Liability Derivatives ​ ​ Location on ​ Fair Value at December 31, ​ Fair Value at December 31, (Dollars in thousands) Balance Sheet 2022 2021 2022 2021 Interest rate contracts Prepaid expenses and other assets ​ $ — ​ $ 9 ​ $ — ​ $ — ​ Interest rate contracts Accounts payable and accrued expenses ​ — ​ — ​ — ​ 9 ​ Total derivatives ​ ​ ​ $ — ​ $ 9 ​ $ — ​ $ 9 ​ ​ Gains and losses on derivatives net to zero for the years ended December 31, 2022 and 2021.

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2022
Premises and Equipment
Premises and Equipment	(10) Premises and Equipment ​ Premises and equipment are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Land ​ $ 585 ​ $ 585 ​ Buildings and improvements ​ 1,400 ​ 1,400 ​ Leasehold improvements ​ 17,949 ​ 14,683 ​ Furniture, fixtures and equipment ​ 6,766 ​ 6,062 ​ Automobiles ​ 130 ​ 118 ​ ​ ​ 26,830 ​ 22,848 ​ Less accumulated depreciation and amortization ​ (19,494) ​ (18,783) ​ ​ ​ 7,336 ​ 4,065 ​ Construction in progress ​ 263 ​ — ​ Total ​ $ 7,599 ​ $ 4,065 ​ ​ Depreciation expense was $1.2 million for the years ended December 31, 2022 and 2021.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2022
Deposits
Deposits	(11) Deposits ​ Deposit accounts by type are summarized with their respective weighted-average interest rates as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2022 ​ 2021 (Dollars in thousands) Amount Rate Amount Rate Non-interest bearing ​ $ 68,095 — % $ 69,980 — % Savings accounts ​ 910,652 0.13 ​ 1,085,255 0.07 ​ Certificates of deposit ​ 429,687 2.67 ​ 225,054 0.85 ​ Money market ​ 5,372 0.10 ​ 5,368 0.10 ​ Checking and Super NOW ​ 302,346 0.02 ​ 296,171 0.02 ​ Total ​ $ 1,716,152 0.74 % $ 1,681,828 0.16 % ​ ​ ​ ​ ​ ​ ​ Maturing in: ​ ​ 2023 ​ $ 356,940 ​ 2024 ​ 56,679 ​ 2025 ​ 6,264 ​ 2026 ​ 4,360 ​ 2027 ​ 5,444 ​ Total ​ $ 429,687 ​ ​ Certificates of deposit with balances greater than or equal to $250,000 totaled $257.9 million and $109.6 million at December 31, 2022 and 2021, respectively. Deposit accounts in the Bank are insured by the FDIC, generally up to a maximum of $250,000 per account owner. ​ Interest expense by type of deposit is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Savings ​ $ 949 ​ $ 1,074 ​ Certificates of deposit and money market ​ 3,914 ​ 2,845 ​ Checking and Super NOW ​ 62 ​ 56 ​ Total ​ $ 4,925 ​ $ 3,975 ​ ​ At December 31, 2022 and 2021, overdrawn deposit accounts totaled $35,000 and $12,000, respectively, and have been reclassified as loans in the Consolidated Balance Sheets. ​ In the normal course of business, certain directors and executive officers (and their associated and affiliated parties) maintain deposit accounts with the Company totaling $3.9 million and $12.2 million at December 31, 2022 and 2021, respectively.

Advances from the Federal Home

Advances from the Federal Home Loan Bank	12 Months Ended
	Dec. 31, 2022
Advances from the Federal Home Loan Bank
Advances from the Federal Home Loan Bank	(12) Advances from the Federal Home Loan Bank ​ Federal Home Loan Bank advances are secured by a blanket pledge on the Bank’s assets not otherwise pledged. At December 31, 2022 and 2021, our credit line with the FHLB Des Moines was equal to 45% of the Bank’s total assets and we had the capacity to borrow an additional $769.1 million and $800.9 million, respectively. ​ During 2021, we restructured $20.0 million of FHLB advances which lowered the average cost of FHLB advances from 1.52% to 1.45%, and extended the average maturity date by 0.4 years . The restructuring was accounted for as a continuation of the existing borrowings with any prepayment fees recognized as an adjustment to the future cost of the restructured advances. There were no FHLB advances restructured in 2022. ​ Advances outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2022 ​ 2021 ​ ​ ​ Weighted ​ ​ Weighted ​ ​ ​ Average ​ ​ ​ ​ Average ​ (Dollars in thousands) Amount ​ Rate ​ Amount ​ Rate ​ Due within one year ​ $ 24,000 1.27 % $ — — % Due over 1 year to 2 years ​ ​ 82,000 1.40 ​ ​ 24,000 1.27 ​ Due over 2 years to 3 years ​ 25,000 1.58 ​ 82,000 1.40 ​ Due over 3 years to 4 years ​ ​ 10,000 1.97 ​ 25,000 1.58 ​ Due over 4 years to 5 years ​ — — ​ 10,000 1.97 ​ Total ​ $ 141,000 1.45 % $ 141,000 1.45 % ​

Securities Sold Under Agreement

Securities Sold Under Agreements to Repurchase	12 Months Ended
	Dec. 31, 2022
Securities Sold Under Agreements to Repurchase
Securities Sold Under Agreements to Repurchase	(13) Securities Sold Under Agreements to Repurchase ​ Securities sold under agreements to repurchase are treated as financings and the obligations to repurchase the identical securities sold are reflected as a liability with the securities collateralizing the agreements classified as an asset. Securities sold under agreements to repurchase are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 December 31, 2021 Weighted Weighted Repurchase Average Repurchase Average (Dollars in thousands) Liability Rate Liability Rate Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Over 1 year to 2 years ​ $ 5,000 1.81 % $ — — % Over 2 years to 3 years ​ ​ 5,000 ​ 1.73 ​ ​ 5,000 ​ 1.88 ​ Over 3 years to 4 years ​ — — ​ ​ 5,000 1.73 ​ Total ​ $ 10,000 1.81 % $ 10,000 1.81 % ​ Below is a summary comparing the carrying value and fair value of securities pledged to secure repurchase agreements, the repurchase liability, and the amount at risk at December 31, 2022. The amount at risk is the greater of the carrying value or fair value over the repurchase liability and refers to the potential loss to the Company if the secured lender fails to return the security at the maturity date of the agreement. All the agreements to repurchase are with JP Morgan Securities and the securities pledged are mortgage-backed securities issued and guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. The repurchase liability cannot exceed of the fair value of securities pledged. In the event of a decline in the fair value of securities pledged to less than the required amount due to market conditions or principal repayments, the Company is obligated to pledge additional securities or other suitable collateral to cure the deficiency. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Carrying Fair Average Value of Value of Repurchase Amount Months to (Dollars in thousands) Securities Securities Liability at Risk Maturity Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Over 90 days ​ $ 13,562 ​ $ 11,351 ​ $ 10,000 ​ $ 3,562 24 ​ ​

Offsetting of Financial Liabili

Offsetting of Financial Liabilities	12 Months Ended
	Dec. 31, 2022
Offsetting of Financial Liabilities
Offsetting of Financial Liabilities	(14) Offsetting of Financial Liabilities ​ Securities sold under agreements to repurchase are subject to a right of offset in the event of default. See Note 13, Securities Sold Under Agreements to Repurchase, for additional information. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net Amount of Gross Amount Not Offset in the Gross Amount Gross Amount Liabilities Balance Sheet of Recognized Offset in the Presented in the Financial Cash Collateral (Dollars in thousands) Liabilities Balance Sheet Balance Sheet Instruments ​ Pledged Net Amount December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Taxes
Income Taxes	(15) Income Taxes ​ Allocation of federal and state income taxes between current and deferred provisions is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Current ​ ​ ​ ​ ​ ​ ​ Federal ​ $ 2,911 ​ $ 4,466 ​ State ​ 1,317 ​ 1,602 ​ ​ ​ 4,228 ​ 6,068 ​ Deferred ​ ​ ​ ​ ​ ​ ​ Federal ​ 990 ​ 205 ​ State ​ 100 ​ 100 ​ ​ ​ 1,090 ​ 305 ​ Total ​ $ 5,318 ​ $ 6,373 ​ ​ The federal statutory corporate tax rate for the years ended December 31, 2022 and 2021 was 21% . A reconciliation of the tax provision based on the statutory corporate rate on pretax income and the provision for taxes as shown in the accompanying Consolidated Statements of Income is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Income tax expense at statutory rate ​ $ 4,510 ​ $ 4,999 ​ Income tax effect of: ​ ​ ​ ​ ​ ​ ​ State income taxes, net of federal income tax benefits ​ 1,079 ​ 1,274 ​ Other tax-exempt income ​ (166) ​ (164) ​ Share-based compensation ​ 9 ​ 1 ​ Meal and entertainment expenses ​ ​ 49 ​ ​ 54 ​ Non-deductible executive compensation ​ ​ 119 ​ ​ 127 ​ Recovery on bank-owned life insurance ​ ​ (216) ​ ​ — ​ Other ​ (66) ​ 82 ​ Total income tax expense ​ $ 5,318 ​ $ 6,373 ​ Effective income tax rate ​ 24.76 % 26.78 % ​ The components of income taxes payable (receivable) are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Current taxes (receivable) payable: ​ ​ ​ ​ ​ ​ ​ Federal ​ $ (519) ​ $ 245 ​ State ​ 1,357 ​ 1,618 ​ ​ ​ $ 838 ​ $ 1,863 ​ Deferred taxes (receivable) payable: ​ ​ ​ ​ ​ ​ ​ Federal ​ $ (707) ​ $ (1,112) ​ State ​ (936) ​ (815) ​ ​ ​ $ (1,643) ​ $ (1,927) ​ ​ The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are presented below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Deferred tax assets: ​ ​ ​ ​ ​ ​ ​ Premises and equipment ​ $ — ​ $ 473 ​ Hawaii franchise tax ​ 377 ​ 454 ​ Allowance for loan losses ​ 541 ​ 711 ​ Employee benefit plans ​ 2,714 ​ 2,703 ​ Equity incentive plan ​ 141 ​ 151 ​ Deferred compensation ​ 199 ​ 240 ​ Net lease liability ​ ​ 212 ​ ​ 203 ​ Unrealized loss on securities available for sale ​ ​ 725 ​ ​ — ​ Other ​ 16 ​ 44 ​ ​ ​ 4,925 ​ 4,979 ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ ​ Deferred loan costs ​ 2,601 ​ 2,654 ​ Premises and equipment ​ ​ 254 ​ ​ — ​ FHLB stock dividends ​ 125 ​ 126 ​ Prepaid expense ​ 226 ​ 186 ​ Premiums on loans sold ​ 76 ​ 86 ​ ​ ​ 3,282 ​ 3,052 ​ Net deferred tax assets ​ $ 1,643 ​ $ 1,927 ​ ​ Deferred tax assets and liabilities at December 31, 2022 and 2021 were calculated using federal corporate tax rates of 21% . ​ In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income, and tax planning strategies in making this assessment. Based upon the level of historical taxable income and projections for future taxable income over the periods in which the deferred tax assets are deductible, management believes it is more likely than not the Company will realize the benefits of these deductible differences. The amount of the deferred tax assets considered realizable, however, could be reduced in the near term if estimates of future taxable income are reduced. There was

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2022
Employee Benefit Plans
Employee Benefit Plans	(16) Employee Benefit Plans ​ The Company has a noncontributory defined benefit pension plan (Pension Plan) that covers certain employees with at least one year of service. The benefits are based on years of service and the employees’ compensation during the service period. The Company’s policy is to accrue the actuarially determined pension costs and to fund pension costs within regulatory guidelines. The Company reviews its assumptions on an annual basis and makes modifications to the assumptions based on current rates and trends when it is appropriate to do so. The effect of modifications to those assumptions is recorded in accumulated other comprehensive income beginning in 2006 and amortized to net periodic benefit cost over future periods using the corridor method. The Company believes that the assumptions utilized in recording its obligations under the plan are reasonable based on its experience and market conditions. ​ In 2008, the Board of Directors approved changes to the Company’s Pension Plan. Effective December 31, 2008, there are no further accruals of benefits for any participants and benefits do not increase with any additional years of service. Employees already enrolled in the Pension Plan as of December 31, 2008 will be have at least five years of service. For employees with less than five years of service, vesting would occur at the employee’s five-year anniversary date. ​ In addition, the Company sponsors a Supplemental Employee Retirement Plan (SERP), a noncontributory supplemental retirement benefit plan, which covers certain current and former employees of the Company for amounts in addition to those provided under the Pension Plan. ​ The following table sets forth the status of the Pension Plan and SERP at the dates indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan ​ SERP ​ ​ December 31, (Dollars in thousands) 2022 2021 2022 2021 Accumulated benefit obligation at end of year ​ $ 15,865 ​ $ 20,943 ​ $ 9,947 ​ $ 9,915 ​ Change in projected benefit obligation: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ 20,943 ​ $ 24,130 ​ $ 9,915 ​ $ 9,866 ​ Service cost (income) ​ 118 ​ 105 ​ (135) ​ (111) ​ Interest cost ​ 597 ​ 547 ​ 179 ​ 177 ​ Actuarial gain ​ (4,802) ​ (2,885) ​ — ​ — ​ Benefits paid ​ (990) ​ (954) ​ (11) ​ (17) ​ Benefit obligation at end of year ​ 15,866 ​ 20,943 ​ 9,948 ​ 9,915 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ 23,125 ​ 21,151 ​ — ​ — ​ Actual return on plan assets ​ (3,799) ​ 2,928 ​ — ​ — ​ Employer contributions ​ — ​ — ​ 11 ​ 17 ​ Benefits paid ​ (990) ​ (954) ​ (11) ​ (17) ​ Fair value of plan assets at end of year ​ 18,336 ​ 23,125 ​ — ​ — ​ Funded status at end of year ​ $ 2,470 ​ $ 2,182 ​ $ (9,948) ​ $ (9,915) ​ Amounts recognized in the Consolidated Balance Sheets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Prepaid expenses and other assets (Accounts payable and accrued expenses) ​ $ 2,470 ​ $ 2,182 ​ $ (9,948) ​ $ (9,915) ​ Amounts recognized in accumulated other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial loss ​ $ 7,708 ​ $ 7,401 ​ $ — ​ $ — ​ Prior service cost ​ 124 ​ 129 ​ — ​ — ​ Accumulated other comprehensive loss, before tax ​ $ 7,832 ​ $ 7,530 ​ $ — ​ $ — ​ ​ The accumulated benefit obligation experienced actuarial gains of $4.8 million and $2.9 million in 2022 and 2021, respectively. The actuarial gains are attributed to an increase in the discount rate used to calculate the benefit obligation. In 2021, the actuarial gain was also due to actual benefit payments, rather than estimated payments, used to calculate the benefit obligation. ​ The following table sets forth the changes recognized in accumulated other comprehensive loss for the years indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan ​ ​ Year Ended December 31, (Dollars in thousands) 2022 2021 Accumulated other comprehensive loss at beginning of year, before tax ​ $ 7,530 ​ $ 12,222 ​ Actuarial net loss (gain) arising during the period ​ 517 ​ (4,372) ​ Amortizations (recognized in net periodic benefit cost): ​ ​ ​ ​ ​ ​ ​ Actuarial loss ​ (210) ​ (315) ​ Prior service cost ​ (5) ​ (5) ​ Total recognized in other comprehensive loss ​ 302 ​ (4,692) ​ Accumulated other comprehensive loss at end of year, before tax ​ $ 7,832 ​ $ 7,530 ​ ​ For the years ended December 31, 2022 and 2021, the following weighted average assumptions were used to determine benefit obligations at the end of the year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan ​ SERP ​ ​ Year Ended December 31, ​ 2022 2021 2022 2021 Assumptions used to determine the year-end benefit obligations: ​ ​ ​ ​ ​ ​ ​ ​ ​ Discount rate 5.40 % 2.90 % 5.00 % 5.00 % Rate of compensation increase N/A ​ N/A ​ 5.00 % 5.00 % ​ The dates used to determine retirement measurements for the Pension Plan were December 31, 2022 and 2021. ​ The Company’s investment strategy for the Pension Plan is to maintain a consistent rate of return with primary emphasis on capital appreciation and secondary emphasis on income to enhance the purchasing power of the plan’s assets over the long-term and to preserve capital. The investment policy establishes a target allocation for each asset class that is reviewed periodically and rebalanced when considered appropriate. Normal target allocations at December 31, 2022 were bonds. Equity securities primarily include stocks, investment in exchange traded funds and large-cap, mid-cap and small-cap mutual funds. Bonds include U.S. Treasuries, mortgage-backed securities and corporate bonds of companies in diversified industries. Other types of investments include money market funds and savings accounts opened with the Company. ​ As of December 31, 2022 and 2021, the Pension Plan’s assets measured at fair value were classified as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of Measurements at Report Date Using: ​ ​ ​ ​ ​ Quoted Prices ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ in Active ​ Significant ​ ​ ​ ​ ​ ​ ​ ​ Markets for ​ Other ​ Significant ​ ​ ​ ​ ​ Identical ​ Observable ​ Unobservable ​ ​ Total Fair ​ Assets ​ Inputs ​ Inputs (Dollars in thousands) ​ Value ​ (Level 1) ​ (Level 2) ​ (Level 3) December 31, 2022: ​ ​ ​ ​ ​ Cash ​ $ 1,452 ​ $ 1,452 ​ $ — ​ $ — ​ Equities ​ 11,659 ​ 11,659 ​ — ​ — ​ Mutual funds (1) ​ 5,225 ​ 5,225 ​ — ​ — ​ Total ​ $ 18,336 ​ $ 18,336 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 1,017 ​ $ 1,017 ​ $ — ​ $ — ​ Equities ​ 16,276 ​ 16,276 ​ — ​ — ​ Mutual funds (1) ​ 5,832 ​ 5,832 ​ — ​ — ​ Total ​ $ 23,125 ​ $ 23,125 ​ $ — ​ $ — ​ (1) This category includes mutual funds that invest in equities and bonds. The mutual fund managers have the ability to change the amounts invested in equities and bonds depending on their investment outlook. ​ Estimated future benefit payments reflecting expected future service at December 31, 2022 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension ​ ​ (Dollars in thousands) ​ Plan ​ SERP 2023 ​ $ 998 ​ $ — ​ 2024 ​ 1,016 ​ 8,733 ​ 2025 ​ 1,153 ​ 125 ​ 2026 ​ 1,216 ​ 125 ​ 2027 ​ 1,233 ​ 125 ​ 2028 - 2032 ​ 6,166 ​ 624 ​ Total ​ $ 11,782 ​ $ 9,732 ​ ​ For the years ended December 31, 2022 and 2021, the following weighted average assumptions were used to determine net periodic benefit cost for the fiscal years shown: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan SERP ​ ​ Year Ended December 31, ​ 2022 2021 2022 2021 Assumptions used to determine the net periodic benefit cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ Discount rate 2.90 % 2.50 % 5.00 % 5.03 % Expected return on plan assets 6.75 ​ 7.00 ​ - ​ - ​ Rate of compensation increase N/A ​ N/A ​ 5.00 ​ 5.00 ​ ​ The components of net periodic benefit cost were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan SERP ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2022 2021 2022 2021 Net periodic benefit (income) cost for the year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service cost (income) ​ $ 118 ​ $ 105 ​ $ (135) ​ $ (111) ​ Interest cost ​ 597 ​ 547 ​ 179 ​ 177 ​ Expected return on plan assets ​ (1,520) ​ (1,441) ​ — ​ — ​ Amortization of prior service cost ​ 5 ​ 5 ​ — ​ — ​ Recognized actuarial loss ​ 210 ​ 315 ​ — ​ — ​ Recognized curtailment loss ​ — ​ — ​ — ​ — ​ Net periodic benefit (income) cost for the year: ​ $ (590) ​ $ (469) ​ $ 44 ​ $ 66 ​ ​ The service cost component of net periodic benefit cost is included in salaries and employee benefits in the Consolidated Statements of Income. The other components of net periodic benefit cost including interest cost, the return on plan assets and amortization of net loss are reported in other income. ​ The expected return on plan assets is based on the weighted-average long-term rates of return for the types of assets held in the plan. The expected return on plan assets is adjusted when there is a change in the expected long-term rate of return or in the composition of assets held in the plan. The discount rate is based on the return of high-quality fixed-income investments that can be used to fund the benefit payments under the Company’s defined benefit plan. ​ The Company does not expect to make any contributions to the Pension Plan or the SERP in 2023. ​ The Company also has a 401(k) defined contribution plan and profit sharing plan covering all employees after one year of service. The 401(k) plan provides for employer matching contributions, as determined by the Company, based on a percentage of employees’ contributions subject to a maximum amount defined in the plan agreement. The Company’s 401(k) matching contributions, based on , respectively. The Company contributes to the profit sharing plan an amount determined by the Board of Directors.

Employee Stock Ownership Plan

Employee Stock Ownership Plan	12 Months Ended
	Dec. 31, 2022
Employee Stock Ownership Plan
Employee Stock Ownership Plan
Employee Stock Ownership Plan	(17) Employee Stock Ownership Plan ​ Effective January 1, 2009, Territorial Savings Bank adopted an Employee Stock Ownership Plan (ESOP) for eligible employees. The ESOP borrowed , of the total number of shares issued by the Company in its initial public offering. The shares were acquired at a price of ​ The loan is secured by the shares purchased with the loan proceeds and will be repaid by the ESOP over the 20 -year term of the loan with funds from Territorial Savings Bank’s contributions to the ESOP and dividends payable on the shares. The interest rate on the ESOP loan is an adjustable rate equal to the Wall Street Journal . The interest rate adjusts annually and will be the prime rate on the first business day of the calendar year. ​ Shares purchased by the ESOP are held by a trustee in an unallocated suspense account, and shares are released annually from the suspense account on a pro-rata basis as principal and interest payments are made by the ESOP to the Company. The trustee allocates the shares released among participants on the basis of each participant’s proportional share of compensation relative to all participants. As shares are committed to be released from the suspense account, Territorial Savings Bank reports compensation expense based on the average fair value of shares released with a corresponding credit to stockholders’ equity. The shares committed to be released are considered outstanding for earnings per share computations. Compensation expense recognized for the years ended December 31, 2022 and 2021 amounted to ​ Shares held by the ESOP trust were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, 2022 2021 Allocated shares ​ 583,474 ​ 540,869 ​ ​ Unearned shares ​ 293,598 ​ 342,531 ​ ​ Total ESOP shares ​ 877,072 ​ 883,400 ​ ​ Fair value of unearned shares, in thousands ​ $ 7,049 ​ $ 8,649 ​ ​ ​ The ESOP restoration plan is a non-qualified plan that provides supplemental benefits to certain executives who are prevented from receiving the full benefits contemplated by the ESOP’s benefit formula. The supplemental cash payments consist of payments representing shares that cannot be allocated to the participants under the ESOP due to IRS limitations imposed on tax-qualified plans. We accrue for these benefits over the period during which employees provide services to earn these benefits. For the years ended December 31, 2022 and 2021, we accrued

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2022
2010 and 2019 Equity Incentive Plans
Share-Based Compensation
Share-Based Compensation	(18) Share-Based Compensation ​ The shareholders of Territorial Bancorp Inc. adopted the 2010 Equity Incentive Plan and the 2019 Equity Incentive Plan. These plans provide for the award of stock options and restricted stock to key officers and directors. In accordance with the Compensation — Stock Compensation topic of the FASB ASC, the cost of the equity incentive plans is based on the fair value of the awards on the grant date. The fair value of time-based restricted stock is based on the closing price of the Company’s stock on the grant date. The fair value of performance-based stock that will vest based on a performance condition is based on the closing price of the Company’s stock on the date of grant. The fair value of performance-based restricted stock that will vest on a market condition is based on a Monte Carlo valuation of the Company’s stock on the date of grant. These assumptions are based on our judgments regarding future events, are subjective in nature, and cannot be determined with precision. The cost of the awards will be recognized on a straight-line basis over the three five vesting period during which participants are required to provide services in exchange for the awards. No new awards can be made under the 2010 Equity Plan, but awards previously made can continue to vest. There are ​ The Company recognized compensation expense, measured as the fair value of the share-based award on the date of grant, on a straight-line basis over the vesting period. Share-based compensation is recorded in the Consolidated Statements of Income as a component of salaries and employee benefits with a corresponding increase in stockholders’ equity. The table below presents information on compensation expense and the related tax benefit for all share-based awards: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2022 2021 Compensation expense ​ $ 480 ​ $ 351 ​ Income tax benefit ​ 131 ​ 96 ​ ​ Stock Options ​ The table below presents the stock option activity of the Company: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Aggregate Average Remaining Intrinsic Exercise Contractual Value Options Price Life (years) (in thousands) Options outstanding at December 31, 2020 3,085 ​ $ 23.62 1.67 ​ $ 1 ​ Granted — ​ — — ​ — ​ Exercised — ​ — — ​ — ​ Forfeited — ​ — — ​ — ​ Expired — ​ — — ​ — ​ Options outstanding at December 31, 2021 3,085 ​ $ 23.62 0.67 ​ $ 5 ​ Granted — ​ — — ​ — ​ Exercised — ​ — — ​ — ​ Forfeited — ​ — — ​ — ​ Expired 3,085 ​ — — ​ — ​ Options outstanding at December 31, 2022 — ​ $ — — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options vested and exercisable at December 31, 2022 — ​ $ — — ​ $ — ​ ​ ​ As of December 31, 2022, the Company had no unrecognized compensation costs related to the stock option plan. ​ Restricted Stock ​ Restricted stock awards are accounted for as a fixed grant using the fair value of the Company’s stock at the time of grant. Unvested restricted stock may not be disposed of or transferred during the vesting period. Restricted stock carries the right to receive dividends, although dividends attributable to restricted stock may be retained by the Company until the shares vest, at which time they are paid to the award recipient. Unvested restricted stock that is time-based contain nonforeitable dividend rights. Accrued dividends on restricted stock that do not vest based on performance or market conditions are forfeited. ​ The table below presents the time-based restricted stock activity: ​ ​ ​ ​ ​ ​ ​ ​ Weighted Average Grant Restricted Date Fair Stock Value Unvested at December 31, 2020 ​ 23,695 ​ $ 24.24 ​ Granted 10,849 ​ 26.67 ​ Vested 11,336 ​ 25.81 ​ Forfeited — ​ — ​ Unvested at December 31, 2021 23,208 ​ $ 24.61 ​ Granted 12,013 ​ 23.77 ​ Vested 11,557 ​ 24.68 ​ Forfeited — ​ — ​ Unvested at December 31, 2022 23,664 ​ $ 24.15 ​ ​ During the year ended December 31, 2022, the Company issued 12,013 shares of time-vested restricted stock to certain members of executive management under the 2019 Equity Incentive Plan. The fair value of the restricted stock is based on the value of the Company’s stock on the date of grant. Time-vested restricted stock will vest over ​ As of December 31, 2022, the Company had $251,000 of unrecognized compensation costs related to time-vested restricted stock. The unrecognized compensation costs are expected to be recognized over a weighted average period of ​ The table below presents the performance-based restricted stock units (PRSUs) that will vest on a performance condition: ​ ​ ​ ​ ​ ​ ​ Performance- ​ ​ ​ ​ Based Restricted ​ ​ ​ Stock Units Weighted ​ ​ Based on a ​ Average Grant ​ ​ Performance ​ Date Fair Condition Value Unvested at December 31, 2020 40,585 ​ $ 25.83 Granted 13,016 ​ 26.67 Vested 7,473 ​ 30.73 Forfeited 4,545 ​ 30.73 Unvested at December 31, 2021 41,583 ​ $ 24.68 Granted 14,412 ​ 23.77 Vested 7,670 ​ 27.30 Forfeited 4,768 ​ 27.30 Unvested at December 31, 2022 43,557 ​ $ 23.63 ​ During the year ended December 31, 2022, the Company issued 14,412 PRSUs to certain members of executive management under the 2019 Equity Incentive Plan. These PRSUs will vest after they are granted after our Compensation Committee determines whether a performance condition that compares the Company’s return on average equity to the SNL Bank Index is achieved. Depending on the Company’s performance, the actual number of these PRSUs that are issued at the end of the vesting period can vary between of the target award. For the PRSUs, an estimate is made of the number of shares expected to vest based on the probability that the performance criteria will be achieved to determine the amount of compensation expense to be recognized. This estimate is re-evaluated quarterly and total compensation expense is adjusted for any change in the current period. ​ The fair value of these PRSUs is based on the fair value of the Company’s stock on the date of grant. As of December 31, 2022, the Company had of unrecognized compensation costs related to these PRSUs. The unrecognized compensation costs are expected to be recognized over a weighted average period of years. Performance will be measured over a period and will be cliff vested. ​ The table below presents the PRSUs that will vest on a market condition: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Performance- ​ ​ ​ ​ ​ Based Restricted ​ Monte Carlo ​ ​ Stock Units ​ Valuation of ​ ​ Based on a ​ the Company's Market Condition Stock Unvested at December 31, 2020 10,147 ​ $ 24.69 Granted 3,254 ​ 25.94 Vested 1,628 ​ 28.32 Forfeited 1,377 ​ 28.32 Unvested at December 31, 2021 10,396 ​ $ 24.03 Granted 3,603 ​ 24.42 Vested — ​ — Forfeited 3,110 ​ 24.45 Unvested at December 31, 2022 10,889 ​ $ 24.04 ​ During the year ended December 31, 2022, the Company issued 3,603 of PRSUs to certain members of executive management under the 2019 Equity Incentive Plan. These PRSUs will vest after they are granted after our Compensation Committee determines whether a market condition that compares the Company’s total stock return to the SNL Bank Index is achieved. The number of shares that will be expensed will not be adjusted for performance and will be cliff vested. The market condition is measured quarterly by comparing the Company’s three-year average total stock return to a peer group of other banks. The Company’s percentile ranking in the peer group determines how many PRSUs will vest. The fair value of these PRSUs is based on a Monte Carlo valuation of the Company’s stock on the date of grant. The assumptions which were used in the Monte Carlo valuation of the PRSUs are: ​ Grant date: April 4, 2022 Performance period: January 1, 2022 to December 31, 2024 2.74 year risk-free rate on grant date: 2.56% December 31, 2021 closing price: $25.25 Closing stock price on date of grant: $23.77 Annualized volatility (based on 2.74 year historical volatility as of the grant date): 38.2% ​ As of December 31, 2022, the Company had $241,000 of unrecognized compensation costs related to the PRSUs that are based on a market condition. The unrecognized compensation costs are expected to be recognized over a weighted average period of years.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2022
Earnings Per Share
Earnings Per Share	(19) Earnings Per Share ​ The table below presents the information used to compute basic and diluted earnings per share: ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, (Dollars in thousands, except per share data) 2022 2021 Net income ​ $ 16,156 ​ $ 17,430 ​ Income allocated to participating securities ​ ​ (98) ​ ​ (75) ​ Net income available to common shareholders ​ $ 16,058 ​ $ 17,355 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average number of shares used in: ​ ​ ​ ​ ​ ​ ​ Basic earnings per share ​ 8,865,946 ​ 9,059,204 ​ Dilutive common stock equivalents: ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ 54,768 ​ 51,131 ​ Diluted earnings per share ​ 8,920,714 ​ 9,110,335 ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income per common share, basic ​ $ 1.81 ​ $ 1.92 ​ Net income per common share, diluted ​ $ 1.80 ​ $ 1.90 ​ ​

Other Comprehensive Loss

Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2022
Other Comprehensive Loss
Other Comprehensive Loss	(20) Other Comprehensive Loss ​ The table below presents the changes in the components of accumulated other comprehensive loss, net of taxes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unfunded Unrealized Pension (Gain)/Loss on (Dollars in thousands) Liability Securities Total December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of year ​ $ 5,524 ​ $ — ​ $ 5,524 ​ Other comprehensive loss, net of taxes ​ 222 ​ 1,998 ​ 2,220 ​ Net current period other comprehensive loss ​ 222 ​ 1,998 ​ 2,220 ​ Balances at end of year ​ $ 5,746 ​ $ 1,998 ​ $ 7,744 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of year ​ $ 8,967 ​ $ (276) ​ $ 8,691 ​ Other comprehensive (income) loss, net of taxes ​ (3,443) ​ 3 ​ (3,440) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 273 ​ 273 ​ Net current period other comprehensive (income) loss ​ (3,443) ​ 276 ​ (3,167) ​ Balances at end of year ​ $ 5,524 ​ $ — ​ $ 5,524 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The table below presents the tax effect on each component of other comprehensive income and loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ 2021 Pretax ​ ​ After Tax Pretax ​ ​ After Tax (Dollars in thousands) Amount ​ Tax ​ Amount ​ Amount ​ Tax ​ Amount Unfunded pension liability ​ $ 302 ​ $ (80) ​ $ 222 ​ $ (4,692) ​ $ 1,249 ​ $ (3,443) ​ Unrealized loss on securities ​ 2,723 ​ (725) ​ 1,998 ​ 4 ​ (1) ​ 3 ​ Amount reclassified from other comprehensive income ​ — ​ — ​ — ​ 373 ​ (100) ​ 273 ​ Total ​ $ 3,025 ​ $ (805) ​ $ 2,220 ​ $ (4,315) ​ $ 1,148 ​ $ (3,167) ​ ​

Commitments

Commitments	12 Months Ended
	Dec. 31, 2022
Commitments
Commitments	(21) Commitments ​ Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any terms or conditions established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since commitments may expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Company evaluates each customer’s creditworthiness on an individual basis. The Company’s policy is to require suitable collateral, primarily real estate, to be provided by customers prior to disbursement of approved loans. At December 31, 2022 and 2021, the Company had loan commitments aggregating to ), respectively, primarily consisting of fixed-rate residential first mortgage loans. In addition to commitments to originate loans, at December 31, 2022 and 2021, the Company had ​ The Company is required by the Federal Reserve Bank to maintain reserves based on the amount of deposits held. Effective March 25, 2020 the Federal Reserve Bank lowered the reserve requirement to zero percent, therefore, there were

Regulatory Capital and Supervis

Regulatory Capital and Supervision	12 Months Ended
	Dec. 31, 2022
Regulatory Capital and Supervision
Regulatory Capital and Supervision	(22) Regulatory Capital and Supervision ​ Territorial Savings Bank and the Company are subject to various regulatory capital requirements, including a risk-based capital measure. The risk-based capital guidelines include both a definition of capital and a framework for calculating risk-weighted assets by assigning balance sheet assets and off-balance sheet items to broad risk categories. The Company is not subject to regulatory capital requirements because its total assets are less than billion. At December 31, 2022 and 2021, Territorial Savings Bank exceeded all of the fully-phased in regulatory captial requirments and is considered to be “well capitalized” under regulatory guidelines. In addition to establishing the minimum regulatory capital requirements, the regulations limit capital distributions and certain discretionary bonus payments to management if the institution does not hold a “capital conservation buffer” consisting of 2.5% of common equity Tier 1 capital to risk-weighted assets above the amount necessary to meet its minimum risk-based capital requirements. The tables below presents the fully-phased in capital required to be considered “well-capitalized” and meet the regulatory capital conservation buffer requirement as a percentage of total and risk-weighted assets and the percentage and the total amount of capital maintained for Territorial Savings Bank and the Company at December 31, 2022 and 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Required Ratio ​ Actual Amount Actual Ratio December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ Tier 1 Leverage Capital ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 5.00 % $ 235,408 ​ 10.87 % Territorial Bancorp Inc. ​ ​ $ 264,295 ​ 12.21 % Common Equity Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 9.00 % $ 235,408 ​ 25.98 % Territorial Bancorp Inc. ​ ​ $ 264,295 ​ 29.16 % Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 10.50 % $ 235,408 ​ 25.98 % Territorial Bancorp Inc. ​ ​ $ 264,295 ​ 29.16 % Total Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 12.50 % $ 237,488 ​ 26.20 % Territorial Bancorp Inc. ​ ​ $ 266,375 ​ 29.39 % ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ Tier 1 Leverage Capital ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 5.00 % $ 235,785 ​ 11.09 % Territorial Bancorp Inc. ​ ​ $ 261,846 ​ 12.31 % Common Equity Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 9.00 % $ 235,785 ​ 26.47 % Territorial Bancorp Inc. ​ ​ $ 261,846 ​ 29.40 % Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 10.50 % $ 235,785 ​ 26.47 % Territorial Bancorp Inc. ​ ​ $ 261,846 ​ 29.40 % Total Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 12.50 % $ 238,515 ​ 26.78 % Territorial Bancorp Inc. ​ ​ $ 264,576 ​ 29.70 % (1) The required Common Equity Tier 1 Risk-Based Capital, Tier 1 Risk-Based Capital and Total Risk-Based Capital ratios are based on the fully-phased in capital ratios in the Basel III capital regulations plus the 2.50% capital conservation buffer. ​ Prompt Corrective Action provisions define specific capital categories based on an institution’s capital ratios. However, the regulators may impose higher minimum capital standards on individual institutions or may downgrade an institution from one capital category to a lower category because of safety and soundness concerns. Failure to meet minimum capital requirements can initiate certain mandatory and possible additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s Consolidated Financial Statements. ​ Prompt Corrective Action provisions impose certain restrictions on institutions that are undercapitalized. The restrictions imposed become increasingly more severe as an institution’s capital category declines from “undercapitalized” to “critically undercapitalized.” ​ At December 31, 2022 and 2021, the Bank’s capital ratios exceeded the minimum capital thresholds for a “well-capitalized” institution. There are ​ Depending on the amount of dividends to be paid, the Bank is required to either notify or make application to the Federal Reserve Bank before dividends are paid to the Company. ​ Legislation enacted in 2018 requires the federal banking agencies, including the Federal Reserve Board, to establish a “community bank leverage ratio” between 8% to 10% of average total consolidated assets for qualifying institutions with assets of less than $10 billion. Institutions with capital meeting the specified requirements and electing to follow the alternative framework would be deemed to comply with the applicable regulatory capital requirements, including the risk based requirements. The federal regulators have adopted 9% as the applicable ratio, effective March 31, 2020, and temporarily reduced the ratio to 8% as a result of the CARES Act, transitioning back to 9% effective January 1, 2022. We have not elected to follow the alternative framework.

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2022
Contingencies
Contingencies	(23) Contingencies ​ The Company is involved in various claims and legal actions arising out of the ordinary course of business. In the opinion of management, the ultimate disposition of these matters will not have a material adverse effect on the Company’s Consolidated Balance Sheets or Consolidated Statements of Income. ​

Revenue Recognition

Revenue Recognition	12 Months Ended
	Dec. 31, 2022
Revenue Recognition
Revenue Recognition	(24) Revenue Recognition ​ The Company’s contracts with customers are generally short-term in nature, with cycles of one year or less. These can range from an immediate term for services such as wire transfers, foreign currency exchanges and cashier’s check purchases, to several days for services such as processing annuity and mutual fund sales. Some contracts may be of an ongoing nature, such as providing deposit account services, including ATM access, check processing, account analysis and check ordering. However, provision of an assessable service and payment for such service is usually concurrent or closely timed. Contracts related to financial instruments, such as loans, investments and debt, are excluded from the scope of this accounting requirement. ​ After analyzing the Company’s revenue sources, including the amount of revenue received, the timing of services rendered and the timing of payment for these services, the Company has determined that the rendering of services and the payment for such services are generally closely matched. Any differences are not material to the Company’s Consolidated Financial Statements. Accordingly, the Company generally records income when payment for services is received. ​ Revenue from contracts with customers is reported in service and other fees and in other noninterest income in the Consolidated Statements of Income. The table below reconciles the revenue from contracts with customers and other revenue reported in those line items: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and ​ ​ ​ ​ (Dollars in thousands) Other Fees Other Total Year ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 1,276 ​ $ 221 ​ $ 1,497 Other revenue ​ ​ 140 ​ ​ 1,783 ​ ​ 1,923 Total ​ $ 1,416 ​ $ 2,004 ​ $ 3,420 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 2,330 ​ $ 177 ​ $ 2,507 Other revenue ​ ​ 133 ​ ​ 550 ​ ​ 683 Total ​ $ 2,463 ​ $ 727 ​ $ 3,190 ​

Leases

Leases	12 Months Ended
	Dec. 31, 2022
Leases
Leases	(25) Leases ​ The table below presents lease costs and other information for the years indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ December 31, (Dollars in thousands) 2022 2021 Lease costs: ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 2,991 ​ $ 3,398 ​ Short-term lease costs ​ 296 ​ 47 ​ Variable lease costs ​ 165 ​ 156 ​ Total lease costs ​ $ 3,452 ​ $ 3,601 ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ $ 3,193 ​ $ 3,372 ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 7,462 ​ $ 4,060 ​ ​ At December 31, 2022, future minimum rental commitments under noncancellable operating leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ 2023 ​ $ 2,894 ​ ​ ​ ​ ​ ​ 2024 ​ 2,757 ​ ​ ​ ​ ​ ​ 2025 ​ 2,137 ​ ​ ​ ​ ​ ​ 2026 ​ 1,974 ​ ​ ​ ​ ​ ​ 2027 ​ 1,896 ​ ​ ​ ​ ​ ​ Thereafter ​ 10,995 ​ ​ ​ ​ ​ ​ Total ​ ​ 22,653 ​ ​ ​ ​ ​ ​ Less lease incentives to be received in 2023 ​ ​ (4,996) ​ ​ ​ ​ ​ ​ Less present value discount ​ ​ (2,362) ​ ​ ​ ​ ​ ​ Present value of leases ​ $ 15,295 ​ ​ ​ ​ ​ ​ ​ The table below presents other lease related information: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ December 31, ​ ​ ​ 2022 ​ 2021 ​ Weighted-average remaining lease term (years) ​ 8.88 ​ ​ 5.93 ​ ​ Weighted-average discount rate ​ ​ 2.03 % ​ ​ 1.83 % ​ ​ The Company leased to a tenant certain property that it owns under a non-cancelable lease that expired during 2021. The Company continues to rent to the tenant on a month-to-month basis. Rental income comprised of minimum rentals for 2022 and 2021 was approximately

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2022
Fair Value
Fair Value	(26) Fair Value of Financial Instruments ​ In accordance with the Fair Value Measurements and Disclosures topic of the FASB ASC, the Company groups its financial assets and liabilities measured or disclosed at fair value into three levels based on the markets in which the financial assets and liabilities are traded and the reliability of the assumptions used to determine fair value as follows: ​ ● ​ ● ​ ● Level 3 — Valuation is generated from model-based techniques that use significant assumptions not observable in the market. These unobservable assumptions reflect management’s own estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques include use of discounted cash flow models and similar techniques that require the use of significant judgment or estimation. ​ In accordance with the Fair Value Measurements and Disclosures topic, the Company bases its fair values on the price that it would expect to receive if an asset were sold or the price that it would expect to pay to transfer a liability in an orderly transaction between market participants at the measurement date. Also as required, the Company maximizes the use of observable inputs and minimizes the use of unobservable inputs when developing fair value measurements. ​ The Company uses fair value measurements to determine fair value disclosures. Investment securities available for sale and derivatives are recorded at fair value on a recurring basis. From time to time, the Company may be required to record other financial assets at fair value on a nonrecurring basis, such as loans held for sale, impaired loans and investments, and mortgage servicing assets. These nonrecurring fair value adjustments typically involve application of the lower of cost or fair value accounting or write-downs of individual assets. ​ Investment Securities Available for Sale. ​ Interest Rate Contracts. The Company may enter into interest rate lock commitments with borrowers on loans intended to be sold. To manage interest rate risk on the lock commitments, the Company may also enter into forward loan sale commitments. The interest rate lock commitments and forward loan sale commitments are treated as derivatives and are recorded at their fair value determined by referring to prices quoted in the secondary market for similar contracts. The fair value inputs are considered Level 2 inputs. Interest rate contracts that are classified as assets are included with prepaid expenses and other assets on the Consolidated Balance Sheet while interest rate contracts that are classified as liabilities are included with accounts payable and accrued expenses. ​ The estimated fair values of the Company’s financial instruments are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ ​ Fair Value Measurements Using (Dollars in thousands) Amount Fair Value Level 1 Level 2 Level 3 December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 40,553 ​ $ 40,553 ​ $ 40,553 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 20,821 ​ ​ 20,821 ​ ​ — ​ ​ 20,821 ​ ​ — ​ Investment securities held to maturity ​ 717,773 ​ ​ 591,084 ​ ​ — ​ ​ 591,084 ​ ​ — ​ Loans receivable, net ​ 1,294,764 ​ ​ 1,180,840 ​ ​ — ​ ​ — ​ ​ 1,180,840 ​ FHLB stock ​ 8,197 ​ ​ 8,197 ​ ​ — ​ ​ 8,197 ​ ​ — ​ FRB stock ​ ​ 3,170 ​ ​ 3,170 ​ ​ — ​ ​ 3,170 ​ ​ — ​ Accrued interest receivable ​ 6,115 ​ ​ 6,115 ​ ​ 23 ​ ​ 1,497 ​ ​ 4,595 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,716,152 ​ ​ 1,708,612 ​ ​ — ​ ​ 1,286,465 ​ ​ 422,147 ​ Advances from the Federal Home Loan Bank ​ 141,000 ​ ​ 133,145 ​ ​ — ​ ​ 133,145 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,440 ​ ​ — ​ ​ 9,440 ​ ​ — ​ Accrued interest payable ​ 701 ​ ​ 701 ​ ​ — ​ ​ 33 ​ ​ 668 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 99,859 ​ $ 99,859 ​ $ 99,859 ​ $ — ​ $ — ​ Investment securities held to maturity ​ 636,442 ​ ​ 634,987 ​ ​ — ​ ​ 634,987 ​ ​ — ​ Loans receivable, net ​ 1,302,824 ​ ​ 1,314,609 ​ ​ — ​ ​ — ​ ​ 1,314,609 ​ FHLB stock ​ 8,173 ​ ​ 8,173 ​ ​ — ​ ​ 8,173 ​ ​ — ​ FRB stock ​ ​ 3,158 ​ ​ 3,158 ​ ​ — ​ ​ 3,158 ​ ​ — ​ Accrued interest receivable ​ 5,786 ​ ​ 5,786 ​ ​ 16 ​ ​ 1,126 ​ ​ 4,644 ​ Interest rate contracts ​ 9 ​ ​ 9 ​ ​ — ​ ​ 9 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,681,828 ​ ​ 1,682,078 ​ ​ — ​ ​ 1,456,773 ​ ​ 225,305 ​ Advances from the Federal Home Loan Bank ​ 141,000 ​ ​ 141,867 ​ ​ — ​ ​ 141,867 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 10,143 ​ ​ — ​ ​ 10,143 ​ ​ — ​ Accrued interest payable ​ 35 ​ ​ 35 ​ ​ — ​ ​ 34 ​ ​ 1 ​ Interest rate contracts ​ 9 ​ ​ 9 ​ ​ — ​ ​ 9 ​ ​ — ​ ​ At December 31, 2022 and 2021, neither the commitment fees received on commitments to extend credit nor the fair value thereof was material to the Consolidated Financial Statements of the Company. ​ The table below presents the balance of assets and liabilities measured at fair value on a recurring basis: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Level 1 Level 2 Level 3 Total ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment securities available for sale ​ $ — ​ $ 20,821 ​ $ — ​ $ 20,821 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts — assets ​ $ — ​ $ 9 ​ $ — ​ $ 9 ​ Interest rate contracts — liabilities ​ — ​ (9) ​ — ​ (9) ​ ​ There were no assets or liabilities measured at fair value on a nonrecurring basis as of December 31, 2022 or 2021.

Parent Company Only

Parent Company Only	12 Months Ended
	Dec. 31, 2022
Parent Company Only
Parent Company Only	(27) Parent Company Only ​ Presented below are the condensed balance sheets, statements of income, and statements of cash flows for Territorial Bancorp Inc. ​ Condensed Balance Sheets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Assets ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 28,515 ​ $ 25,532 ​ Investment in Territorial Savings Bank ​ 227,663 ​ 230,261 ​ Receivable from Territorial Savings Bank ​ 408 ​ 566 ​ Prepaid expenses and other assets ​ 105 ​ 132 ​ Total assets ​ $ 256,691 ​ $ 256,491 ​ Liabilities and Equity ​ ​ ​ ​ ​ ​ ​ Other liabilities ​ $ 141 ​ $ 170 ​ Equity ​ 256,550 ​ 256,321 ​ Total liabilities and equity ​ $ 256,691 ​ $ 256,491 ​ ​ Condensed Statements of Income ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, (Dollars in thousands) 2022 2021 Interest and dividend income: ​ ​ ​ ​ ​ ​ ​ Dividends from Territorial Savings Bank ​ $ 17,500 ​ $ 22,000 ​ Interest-earning deposit with Territorial Savings Bank ​ 4 ​ 5 ​ Total interest and dividend income ​ 17,504 ​ 22,005 ​ ​ ​ ​ ​ ​ ​ ​ ​ Noninterest expense: ​ ​ ​ ​ ​ ​ ​ Salaries ​ 42 ​ 43 ​ Other general and administrative expenses ​ 656 ​ 998 ​ Total noninterest expense ​ 698 ​ 1,041 ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income taxes and equity in undistributed earnings in subsidiaries ​ 16,806 ​ 20,964 ​ Income taxes ​ (209) ​ (288) ​ Income before equity in undistributed earnings in subsidiaries ​ 17,015 ​ 21,252 ​ Equity in undistributed earnings of Territorial Savings Bank, net of dividends ​ (859) ​ (3,822) ​ Net income ​ $ 16,156 ​ $ 17,430 ​ ​ Condensed Statements of Cash Flows ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, (Dollars in thousands) 2022 2021 Cash flows from operating activities: ​ ​ ​ ​ ​ ​ ​ Net income ​ $ 16,156 ​ $ 17,430 ​ Adjustments to reconcile net income to net cash provided by operating activities: ​ ​ ​ ​ ​ ​ ​ Equity in undistributed earnings of Territorial Savings Bank, net of dividends ​ 859 ​ 3,822 ​ Net decrease in prepaid expenses and other assets ​ 1,275 ​ 1,762 ​ Net decrease in other liabilities ​ (263) ​ (366) ​ Net cash provided by operating activities ​ 18,027 ​ 22,648 ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash flows from investing activities: ​ ​ ​ ​ ​ ​ ​ Investment in Territorial Savings Bank ​ — ​ — ​ Net cash used in investing activities ​ — ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash flows from financing activities: ​ ​ ​ ​ ​ ​ ​ Repurchases of common stock ​ (5,973) ​ (5,000) ​ Cash dividends paid ​ (9,071) ​ (10,224) ​ Net cash used in financing activities ​ (15,044) ​ (15,224) ​ Net increase in cash ​ 2,983 ​ 7,424 ​ Cash at beginning of the period ​ 25,532 ​ 18,108 ​ Cash at end of the period ​ $ 28,515 ​ $ 25,532 ​ ​

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2022
Subsequent Events
Subsequent Events	(28) Subsequent Events ​ On January 26, 2023, the Board of Directors of Territorial Bancorp Inc. declared a quarterly cash dividend of $0.23 per share of common stock. The dividend was paid on February 23, 2023 to stockholders of record as of February 9, 2023. ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Basis of Presentation
Description of Business	(a) Description of Business ​ Territorial Bancorp Inc. (the Company), through its wholly-owned subsidiary, Territorial Savings Bank (the Bank), provides loan and deposit products and services primarily to individual customers through 29 branches located throughout Hawaii. We deal primarily in residential mortgage loans in the State of Hawaii. The Company’s earnings depend primarily on its net interest income, which is the difference between the interest income earned on interest-earning assets (loans receivable and investments) and the interest expense incurred on interest-bearing liabilities (deposit liabilities and borrowings). Deposits traditionally have been the principal source of the Bank’s funds for use in lending, meeting liquidity requirements, and making investments. The Company also derives funds from receipt of interest and principal repayments on outstanding loans receivable and investments, borrowings from the Federal Home Loan Bank (FHLB), securities sold under agreements to repurchase, and proceeds from issuance of common stock.
Principles of Consolidation		​ (b) Principles of Consolidation ​ The Consolidated Financial Statements include the accounts and results of operations of Territorial Bancorp Inc. and Territorial Savings Bank and its wholly-owned subsidiaries. Significant intercompany balances and transactions have been eliminated in consolidation. ​
Cash and Cash Equivalents	(c) Cash and Cash Equivalents ​ Cash and cash equivalents includes cash and due from banks, interest-bearing deposits in other banks, federal funds sold, and short-term, highly liquid investments with original maturities of three months or less. ​
Investment Securities	(d) Investment Securities ​ The Company classifies and accounts for its investment securities as follows: (1) held-to-maturity debt securities in which the Company has the positive intent and ability to hold to maturity are reported at amortized cost; (2) trading securities that are purchased for the purpose of selling in the near term are reported at fair value, with unrealized gains and losses included in current earnings; and (3) available-for-sale securities not classified as either held-to-maturity or trading securities are reported at fair value, with unrealized gains and losses excluded from current earnings and reported as a separate component of equity. At December 31, 2022, $20.8 million of securities were classified as available-for-sale and the remaining securites were classified as held-to-maturity. At December 31, 2021, the Company classified all of its investments as held-to-maturity. ​ A decline in the market value of any available-for-sale or held-to-maturity security below cost, that is deemed to be other than temporary, results in an impairment to reduce the carrying amount to fair value. To determine whether impairment is other than temporary, the Company considers the type of the investment, the cause of the decline in value and the amount and duration of the decline in value. It also considers whether it has the intent and ability not to sell and would not be required to sell the security for a sufficient period of time to recover the remaining amortized cost basis. ​ Gains or losses on the sale of investment securities are computed using the specific-identification method. The Company amortizes premiums and accretes discounts associated with investment securities using the interest method over the contractual life of the respective investment security. Such amortization and accretion is included in the interest income line item in the Consolidated Statements of Income. Interest income is recognized when earned. ​
Loans Receivable	(e) Loans Receivable ​ This policy applies to all loan classes. Loans receivable are stated at the principal amount outstanding, less the allowance for loan losses, loan origination fees and costs, and commitment fees. Interest on loans receivable is accrued as earned. The Company has a policy of placing loans on a nonaccrual basis when 90 days or more contractually delinquent or when, in the opinion of management, collection of all or part of the principal balance appears doubtful. For nonaccrual loans, the Company records payments received as a reduction in principal. The Company, considering current information and events regarding the borrowers’ ability to repay their obligations, considers a loan to be impaired when it is probable that the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. When a loan is considered to be impaired, the amount of the impairment is measured based on the present value of expected future cash flows discounted at the loan’s effective interest rate or, if the loan is considered to be collateral dependent, based on the fair value of the collateral less estimated costs to sell. Impairment losses are written off against the allowance for loan losses. For nonaccrual impaired loans, the Company records payments received as a reduction in principal. A nonaccrual loan may be restored to an accrual basis when principal and interest payments are current and full payment of principal and interest is expected.
Loans Held for Sale	​ (f) Loans Held for Sale ​ Loans held for sale are stated at the lower of aggregate cost or market value. Net fees and costs of originating loans held for sale are deferred and are included in the basis for determining the gain or loss on sales of loans held for sale.
Deferred Loan Origination Fees and Unearned Loan Discounts	​ (g) Deferred Loan Origination Fees and Unearned Loan Discounts ​ Loan origination and commitment fees and certain direct loan origination costs are being deferred, and the net amount is recognized over the life of the related loan as an adjustment to yield. Net deferred loan fees are amortized using the interest method over the contractual term of the loan, adjusted for actual prepayments. Net unamortized fees on loans paid in full are recognized as a component of interest income.
Real Estate Owned	​ (h) Real Estate Owned ​ Real estate owned is valued at the time of foreclosure at fair value, less estimated cost to sell, thereby establishing a new cost basis. The Company obtains appraisals based on recent comparable sales to assist management in estimating the fair value of real estate owned. Subsequent to acquisition, real estate owned is valued at the lower of cost or fair value, less estimated cost to sell. Declines in value are charged to expense through a direct write-down of the asset. Costs related to holding real estate are charged to expense while costs related to development and improvements are capitalized. Net gains or losses recognized on the sale of real estate owned are included in other general and administrative expenses. ​
Allowance for Loan Losses	(i) Allowance for Loan Losses ​ The Company maintains an allowance adequate to cover management’s estimate of probable loan losses as of the balance sheet date. The Company’s allowance for loan losses is maintained at a level considered adequate to provide for losses that can be estimated based upon specific and general conditions. All loan losses are charged, and all recoveries are credited, to the allowance for loan losses. Additions to the allowance for loan losses are provided by charges to income based on various factors, which, in the Company’s judgment, deserve current recognition in estimating probable losses. Charge-offs to the allowance are made when management determines that collectability of all or a portion of a loan is doubtful and available collateral is insufficient to repay the loan. ​ General allowances are established for loan losses on a portfolio basis for loans that do not meet the definition of impaired, in accordance with the Receivables topic of the FASB ASC. The portfolio is grouped into similar risk characteristics, primarily loan type and loan-to-value ratio. The Company applies an estimated loss rate to each loan group. The loss rates applied are based upon its loss experience adjusted, as appropriate, for qualitative and environmental factors discussed below. This evaluation is inherently subjective, as it requires material estimates that may be susceptible to significant revisions based upon changes in economic and real estate market conditions. Actual loan losses may be significantly more than the allowance for loan losses the Company has established, which could have a material negative effect on its financial results. ​ Residential mortgage loans represent the largest segment of the Company’s loan portfolio. Residential mortgage loans are secured by a first mortgage on residential real estate in Hawaii and consist primarily of fixed-rate mortgage loans which have been underwritten to Freddie Mac and Fannie Mae guidelines and have similar risk characteristics. The loan loss allowance is determined by first calculating the historical loss rate for this segment of the portfolio. The loss rate may be adjusted for qualitative and environmental factors. The allowance for loan loss is calculated by multiplying the adjusted loss rate by the total loans in this segment of the portfolio. ​ The adjustments to historical loss experience are based on an evaluation of several qualitative and environmental factors, including: ​ ● changes in lending policies and procedures, including changes in underwriting standards and collections, charge-off and recovery practices; ​ ● changes in international, national, regional and local economic business conditions and developments that affect the collectibility of the portfolio; ​ ● changes in the bank’s internal loan review system; ​ ● changes in the experience, depth and ability of personnel in the mortgage loan origination and loan servicing departments; ​ ● changes in the volume and severity of past due loans, the volume of nonaccrual loans and classified assets; ​ ● changes in the nature and volume of loans being originated; ​ ● changes in the value of underlying collateral for collateral dependent loans; ​ ● existence and any changes in concentrations of credit; ​ ● external factors such as competition, legal and regulatory requirements on the level of estimated credit losses in the existing loan portfolio; and ​ ● changes in the amount of loans with payment deferrals. ​ The Company also uses historical loss rates adjusted for qualitative and environmental factors to establish loan loss allowances for the following portfolio segments: ​ ● home equity loans and lines of credit; and ​ ● consumer and other loans. ​ The Company has a limited loss experience for the construction, commercial and other mortgage segment of the loan portfolio. The loan loss allowance on this portfolio segment is determined using the loan loss rate of other financial institutions in the State of Hawaii. The allowance for loan loss is calculated by multiplying the loan loss rate of other financial institutions in the state by the total loans in this segment of the Company’s loan portfolio. ​ The allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. In addition, the unallocated allowance is established to provide for probable losses that have been incurred as of the reporting date but are not reflected in the allocated allowance. ​ While the Company uses the best information available to make evaluations, future adjustments to the allowance may be necessary if conditions differ substantially from the information used in making the evaluations. In addition, as an integral part of their examination process, the bank regulators will periodically review the allowance for loan losses. The bank regulators may require the Company to increase the allowance based on their analysis of information available at the time of their examination.
Transfer of Financial Assets	​ (j) Transfer of Financial Assets ​ Transfers of financial assets are accounted for as sales when control is surrendered. Control is surrendered when the assets have been isolated from the Company, the transferee obtains the right to pledge or exchange the assets without constraint, and the Company does not maintain effective control over the transferred assets. Mortgage loans sold for cash are accounted for as sales as the above criteria have been met. ​ Mortgage loans may also be packaged into securities that are issued and guaranteed by U.S. government-sponsored enterprises or a U.S. government agency. The Company receives of the mortgage-backed securities issued. The mortgage-backed securities received in securitizations are valued at fair value and classified as held-to-maturity. A gain or loss in the securitization transactions is recognized for the difference between the fair value of the mortgage-backed securities received and the amortized cost of the loans securitized. ​ Mortgage loan transfers accounted for as sales and securitizations are without recourse, except for normal representations and warranties provided in sales transactions, and the Company may retain the related rights to service the loans. The retained servicing rights create mortgage servicing assets that are accounted for in accordance with the Transfers and Servicing topic of the FASB ASC. Mortgage servicing assets are initially valued at fair value and subsequently at the lower of cost or fair value and are amortized in proportion to and over the period of estimated net servicing income. The Company uses a discounted cash flow model to determine the fair value of retained mortgage servicing rights. The amount of mortgage servicing rights is immaterial to the financial statement.
Premises and Equipment	​ (k) Premises and Equipment ​ Premises and equipment are stated at cost less accumulated depreciation and amortization. Depreciation is principally computed on the straight-line method over the estimated useful lives of the respective assets. The estimated useful life of buildings and improvements is . Leasehold improvements are amortized on a straight-line basis over the shorter of the lease term or estimated useful life of the asset.
Income Taxes	​ (l) Income Taxes ​ The Company files consolidated federal income tax and consolidated state franchise tax returns. ​ Deferred tax assets and liabilities are recognized using the asset and liability method of accounting for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and net operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. ​ We establish income tax contingency reserves for potential tax liabilities related to uncertain tax positions. A liability for income tax uncertainties would be recorded for unrecognized tax benefits related to uncertain tax positions where it is more likely than not that the position will be sustained upon examination by a taxing authority. ​ As of December 31, 2022 and 2021, the Company had not recognized a liability for income tax uncertainties in the accompanying Consolidated Balance Sheets because management concluded that the Company does not have uncertain tax positions. ​ The Company recognizes interest and penalties related to tax liabilities in other interest expense and other general and administrative expenses, respectively, in the Consolidated Statements of Income. ​ Tax years 2019 to 2021 currently remain subject to examination by the Internal Revenue Service and by the Department of Taxation of the State of Hawaii.
Impairment of Long-Lived Assets	​ (m) Impairment of Long-Lived Assets ​ Long-lived assets, such as premises and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of would be separately presented in the Consolidated Balance Sheets and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated.
Pension Plan	​ (n) Pension Plan ​ Pension benefit costs (returns) are charged (credited) to salaries and employee benefits expense or other income, and the corresponding prepaid (accrued) pension cost is recorded in prepaid expenses and other assets or accounts payable and accrued expenses in the Consolidated Balance Sheets. The Company’s policy is to fund pension costs in amounts that will not be less than the minimum funding requirements of the Employee Retirement Income Security Act of 1974 and will not exceed the maximum tax-deductible amounts. The Company generally funds at least the net periodic pension cost, subject to limits and targeted funded status as determined with the consulting actuary. ​
Share-Based Compensation	(o) Share-Based Compensation ​ The Company grants share-based compensation awards, including restricted stock and restricted stock units, which are either performance-based or time-based. The fair value of the restricted stock and restricted stock unit awards were based on the closing price of the Company’s stock on the date of grant. The cost of these awards are amortized in the Consolidated Statements of Income on a straight-line basis over the vesting period. The amount of performance-based restricted stock units that vest on a performance condition is remeasured quarterly based on how the Company’s return on average equity compares to the SNL Bank Index. The fair value of performance-based restricted stock units that are based on how the Company’s total stock return compares to the SNL Bank Index was measured using a Monte-Carlo valuation. ​
Supplemental Employee Retirement Plan (SERP)	(p) Supplemental Employee Retirement Plan (SERP) ​ The SERP is a noncontributory supplemental retirement plan covering certain current and former employees of the Company. Benefits in the SERP plan are paid after retirement, in addition to the benefits provided by the Pension Plan. The Company accrues SERP costs over the estimated period until retirement by charging salaries and employee benefits expense in the Consolidated Statements of Income, with a corresponding credit to accounts payable and accrued expenses in the Consolidated Balance Sheets. ​
Employee Stock Ownership Plan (ESOP)	(q) Employee Stock Ownership Plan (ESOP) ​ The cost of shares issued to the ESOP, but not yet allocated to participants, is shown as a reduction of stockholders’ equity. Compensation expense is based on the market price of shares as they are committed to be released to participant accounts. Dividends on allocated ESOP shares reduce retained earnings; dividends on unearned ESOP shares reduce debt and accrued interest. ​
Earnings Per Share	(r) Earnings Per Share ​ We have two forms of our outstanding common stock: common stock and unvested restricted stock awards. Holders of unvested restricted stock awards receive dividends at the same rate as common shareholders and they both share equally in undistributed earnings. Unvested restricted stock awards that are time-based contain nonforfeitable rights to dividends or dividend equivalents are considered to be participating securities in the earnings per share computation using the two-class method. Under the two-class method, earnings are allocated to common shareholders and participating securities according to their respective rights to earnings. Unvested restricted stock awards that vest based on performance or market conditions are not considered to be participating securities in the earnings per share calculation because accrued dividends on shares that do not vest are forfeited. ​ Basic earnings per share is computed by dividing net income allocated to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income allocated to common shareholders by the sum of the weighted-average number of shares outstanding plus the dilutive effect of stock options and restricted stock. ESOP shares not committed to be released are not considered outstanding. ​
Common Stock Repurchase Program	(s) Common Stock Repurchase Program ​ The Company adopted common stock repurchase programs in which shares repurchased reduce the amount of shares issued and outstanding. The repurchased shares may be reissued in connection with share-based compensation plans and for general corporate purposes. During 2022 and 2021, the Company repurchased per share, respectively, as part of the repurchase programs authorized by the Board of Directors.
Bank-Owned Life Insurance	​ (t) Bank-Owned Life Insurance ​ The Company’s investment in bank-owned life insurance is based on cash surrender value. The Company invests in bank-owned life insurance to provide a funding source for benefit plan obligations. Bank-owned life insurance also generally provides noninterest income that is nontaxable. Federal regulations generally limit the investment in bank-owned life insurance to of the Bank’s Tier 1 capital plus the allowance for loan losses. At December 31, 2022, this limit was ​
Leases	(u) Leases ​ The Company records a right-of-use (ROU) asset for those leases that convey rights to control use of identified assets for a period of time in exchange for consideration. The Company is also required to record a lease liability for the present value of future payment commitments. The Company leases most of its premises and some vehicles and equipment under operating leases expiring on various dates through 2037. The majority of lease agreements relate to real estate and generally provide that the Company pay taxes, insurance, maintenance and certain other variable operating expenses applicable to the leased premises. Variable lease components and nonlease components are not included in the Company’s computation of the ROU asset or lease liability. The Company also does not include short-term leases in the computation of the ROU asset or lease liability. Short-term leases are leases with a term at commencement of 12 months or less. Short-term lease expense is recorded on a straight-line basis over the term of the lease. Lease agreements do not contain any residual value guarantees or restrictive covenants. ​ The value of the ROU asset and lease liability is impacted by the amount of the periodic payment required, length of the lease term, lease incentives and the discount rate used to calculate the present value of the minimum lease payments. Certain leases have renewal options at the expiration of the lease terms. Generally, option periods are not included in the computation of the lease term, ROU asset or lease liability because the Company is not reasonably certain to exercise renewal options at the expiration of the lease terms. Because the discount rates implicit in our leases are not known, discount rates have been estimated using the rates for fixed-rate, amortizing advances from the FHLB for the approximate terms of the leases. ​
Use of Estimates	(v) Use of Estimates ​ The preparation of the Consolidated Financial Statements requires management to make a number of estimates and assumptions relating to the reported amount of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amount of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include the allowance for loan losses; valuation of certain investment securities and determination as to whether declines in fair value below amortized cost are other than temporary; valuation allowances for deferred income tax assets; mortgage servicing assets; and assets and obligations related to employee benefit plans. Accordingly, actual results could differ from those estimates.
Recently Issued Accounting Pronouncements	​ (w) Recently Issued Accounting Pronouncements ​ In June 2016, the Financial Accounting Standards Board (FASB) issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The ASU changes the threshold for recognizing losses from a “probable” to an “expected” model. The new model is referred to as the current expected credit loss model and applies to loans, leases, held-to-maturity investments and loan commitments. The amendment requires the measurement of all expected credit losses for financial assets as of the reporting date (including historical experience, current conditions and reasonable and supportable forecasts) and enhanced disclosures that will help financial statement users understand the estimates and judgments used in estimating credit losses and evaluating the credit quality of an organization’s portfolio. The amendment is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. In November 2019, the FASB issued an update that delayed the effective date of the amendment for smaller reporting companies, as defined by the Securities and Exchange Commission, to fiscal years beginning after December 15, 2022. The Company is a smaller reporting company. The Company has formed a team that is working on an implementation plan to adopt the amendment. The Company is also working with a consultant to measure expected losses required by the amendment. The Company is finalizing its adoption of the current expected credit loss standard by developing new policies, procedures, internal controls and disclosures which will be used when the standard is adopted. Based on the current composition of the Company’s loan portfolio as of December 31, 2022, and the current expectation of future economic conditions, the allowance for credit losses is expected to increase by million at the January 1, 2023 adoption date. The allowance for credit losses is expected to increase because the new standard measures credit losses over the expected life of the loans in the Company’s loan portfolio. Most of the loans in the Company’s loan portfolio are 30-year mortgage loans which have a long average life. All of the Company's investments in mortgage-backed securities and collateralized mortgage obligations have been issued by Freddie Mac or Fannie Mae, which are U.S. government-sponsored enterprises, or Ginnie Mae, which is a U.S. government agency. These agencies and enterprises guarantee the payment of principal and interest and therefore the Company will not record an allowance on its held-to-maturity or available-for-sale securities. The adoption of the current expected credit loss standard will be recorded by making an after-tax adjustment to retained earnings. Although the adjustment for the adoption of the current expected credit loss standard will reduce retained earnings, the Company will continue to be well-capitalized. ​ In March 2022, the FASB issued ASU 2022-02, Financial Instruments-Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures. The ASU eliminates the accounting guidance for loans modified as troubled debt restructurings by creditors while enhancing disclosure requirements for certain loan refinancings and restructurings by creditors when a borrower is experiencing financial difficulty. Additionally, the ASU requires public business entities to disclose current-period gross write-offs by year of origination for financing receivables and net investments in leases. This ASU will be effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years, upon the Company’s adoption of the amendments in ASU 2016-13. The Company is currently evaluating the effects that ASU 2022-03 will have on its consolidated financial statements. ​ In June 2022, the FASB issued ASU 2022-03, Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions to clarify that contractual sale restrictions should not be considered in the measurement of the fair value of an equity security. The Company owns stock in the Federal Reserve Bank (FRB) and in the FHLB which is valued at historical cost which approximates fair value. Ownership of stock is a condition for services the Company receives from the FRB and FHLB. The stock is not publically traded and can only be issued, exchanged, redeemed or repurchased by the FRB and the FHLB. ASU 2022-03 is effective for fiscal years beginning after December 15, 2023. The Company does not expect the adoption of this ASU to have a material effect on its consolidated financial statements.

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	12 Months Ended
	Dec. 31, 2022
Cash and Cash Equivalents
Schedule of balances of cash and cash equivalents	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Cash and due from banks ​ $ 9,722 ​ $ 11,662 ​ Interest-earning deposits in other banks ​ 30,831 ​ 88,197 ​ Cash and cash equivalents ​ $ 40,553 ​ $ 99,859 ​ ​

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2022
Investment Securities.
Schedule of amortized cost and estimated fair value of investment securities by maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized Estimated (Dollars in thousands) Cost Fair Value Available-for-sale: ​ ​ ​ ​ ​ ​ ​ Due after 10 years ​ $ 23,544 ​ $ 20,821 ​ Total ​ $ 23,544 ​ $ 20,821 ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ Due within 5 years ​ $ 19 ​ $ 18 ​ Due after 5 years through 10 years ​ 12 ​ 12 ​ Due after 10 years ​ 717,742 ​ 591,054 ​ Total ​ $ 717,773 ​ $ 591,084 ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of realized gains and losses and proceeds from sales of securities held to maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Proceeds from sales ​ $ — ​ $ 26,900 Gross gains ​ — ​ 1,840 Gross losses ​ — ​ — ​
Summary of investment securities in an unrealized loss position	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less Than 12 Months 12 Months or Longer Total Unrealized Unrealized Number of Unrealized Description of securities Fair Value Losses Fair Value Losses Securities Fair Value Losses (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enteprises ​ $ 20,821 ​ $ (2,723) ​ $ — ​ $ — 4 ​ $ 20,821 ​ $ (2,723) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ $ 210,128 ​ $ (22,209) ​ $ 377,418 ​ $ (104,542) 148 ​ $ 587,546 ​ $ (126,751) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ $ 482,629 ​ $ (6,976) ​ $ 3,681 ​ $ (178) 43 ​ $ 486,310 ​ $ (7,154) ​ ​

Loans Receivable and Allowanc_2

Loans Receivable and Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2022
Loans Receivable and Allowance for Loan Losses
Schedule of components of loans receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ (Dollars in thousands) 2022 2021 ​ Real estate loans: ​ ​ ​ ​ ​ ​ ​ First mortgages: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential ​ $ 1,253,558 ​ $ 1,267,537 ​ Multi-family residential ​ 6,448 ​ 5,468 ​ Construction, commercial and other ​ 23,903 ​ 18,590 ​ Home equity loans and lines of credit ​ 6,426 ​ 7,121 ​ Total real estate loans ​ 1,290,335 ​ 1,298,716 ​ Other loans: ​ ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ 216 ​ 278 ​ Consumer and other loans ​ 8,381 ​ 8,192 ​ Total other loans ​ 8,597 ​ 8,470 ​ Less: ​ ​ ​ ​ ​ ​ ​ Net unearned fees and discounts ​ (2,136) ​ (1,693) ​ Allowance for loan losses ​ (2,032) ​ (2,669) ​ Total unearned fees, discounts and allowance for loan losses ​ (4,168) ​ (4,362) ​ Loans receivable, net ​ $ 1,294,764 ​ $ 1,302,824 ​ ​
Schedule of activity in allowance for loan losses on loans receivable and by portfolio segment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals Year ended December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of year ​ $ 1,814 ​ $ 435 ​ $ 1 ​ $ 89 ​ $ 330 ​ $ 2,669 ​ (Reversal of provision) provision for loan losses ​ (551) ​ (1) ​ — ​ 47 ​ (71) ​ (576) ​ ​ ​ 1,263 ​ 434 ​ 1 ​ 136 ​ 259 ​ 2,093 ​ Charge-offs ​ — ​ — ​ — ​ (62) ​ — ​ (62) ​ Recoveries ​ — ​ — ​ — ​ 1 ​ — ​ 1 ​ Net charge-offs ​ — ​ — ​ — ​ (61) ​ — ​ (61) ​ Balance, end of year ​ $ 1,263 ​ $ 434 ​ $ 1 ​ $ 75 ​ $ 259 ​ $ 2,032 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of year ​ $ 3,102 ​ $ 406 ​ $ 1 ​ $ 146 ​ $ 607 ​ $ 4,262 ​ (Reversal of provision) provision for loan losses ​ (1,305) ​ 29 ​ — ​ (39) ​ (277) ​ (1,592) ​ ​ ​ 1,797 ​ 435 ​ 1 ​ 107 ​ 330 ​ 2,670 ​ Charge-offs ​ — ​ — ​ — ​ (22) ​ — ​ (22) ​ Recoveries ​ 17 ​ — ​ — ​ 4 ​ — ​ 21 ​ Net recoveries (charge-offs) ​ 17 ​ — ​ — ​ (18) ​ — ​ (1) ​ Balance, end of year ​ $ 1,814 ​ $ 435 ​ $ 1 ​ $ 89 ​ $ 330 ​ $ 2,669 ​ ​
Schedule of balance in allowance for loan losses and the recorded investment in loans by portfolio segment and based on impairment method	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 1,263 ​ 434 ​ 1 ​ 75 ​ 259 ​ 2,032 ​ Total ending allowance balance ​ $ 1,263 ​ $ 434 ​ $ 1 ​ $ 75 ​ $ 259 ​ $ 2,032 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 2,693 ​ $ — ​ $ 16 ​ $ — ​ $ 6 ​ $ 2,715 ​ Collectively evaluated for impairment ​ 1,255,300 ​ 23,775 ​ ​ 6,411 ​ 8,595 ​ — ​ 1,294,081 ​ Total ending loan balance ​ $ 1,257,993 ​ $ 23,775 ​ $ 6,427 ​ $ 8,595 ​ $ 6 ​ $ 1,296,796 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 1,814 ​ 435 ​ 1 ​ 89 ​ 330 ​ 2,669 ​ Total ending allowance balance ​ $ 1,814 ​ $ 435 ​ $ 1 ​ $ 89 ​ $ 330 ​ $ 2,669 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 3,812 ​ $ — ​ $ 19 ​ $ — ​ $ — ​ $ 3,831 ​ Collectively evaluated for impairment ​ 1,267,560 ​ 18,529 ​ 7,103 ​ 8,470 ​ — ​ 1,301,662 ​ Total ending loan balance ​ $ 1,271,372 ​ $ 18,529 ​ $ 7,122 ​ $ 8,470 ​ $ — ​ $ 1,305,493 ​ ​
Schedule of balance of impaired loans individually evaluated for impairment by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid Recorded Principal (Dollars in thousands) Investment Balance December 31, 2022: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,693 ​ $ 3,209 ​ Home equity loans and lines of credit ​ 16 ​ 30 ​ Consumer loans ​ 6 ​ 6 ​ Total ​ $ 2,715 ​ $ 3,245 ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 3,812 ​ $ 4,299 ​ Home equity loans and lines of credit ​ ​ 19 ​ 31 ​ Total ​ $ 3,831 ​ $ 4,330 ​ ​ ​
Schedule of average recorded investment and interest income recognized on impaired loans by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ Average Recorded Interest Income (Dollars in thousands) Investment Recognized 2022: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,776 ​ $ 24 ​ Home equity loans and lines of credit ​ 17 ​ — ​ Consumer loans ​ 6 ​ ​ — ​ Total ​ $ 2,799 ​ $ 24 ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 3,888 ​ $ 36 ​ Home equity loans and lines of credit ​ 21 ​ — ​ Total ​ $ 3,909 ​ $ 36 ​ ​
Schedule of aging of loans and accrual status by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans 90 Days or More 30 - 59 60 - 89 90 Days or Past Due Days Past Days Past More Total Past Loans Not Total Nonaccrual and Still (Dollars in thousands) Due Due Past Due Due Past Due Loans Loans Accruing December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ 409 ​ $ 559 ​ $ 968 ​ $ 1,250,586 ​ $ 1,251,554 ​ $ 2,279 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 6,439 ​ 6,439 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 23,775 ​ 23,775 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 6,427 ​ 6,427 ​ 16 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 217 ​ 217 ​ — ​ — ​ Consumer and other ​ 6 ​ — ​ 6 ​ 12 ​ 8,372 ​ 8,384 ​ 6 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 6 ​ $ 409 ​ $ 565 ​ $ 980 ​ $ 1,295,816 ​ $ 1,296,796 ​ $ 2,301 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 129 ​ $ — ​ $ 244 ​ $ 373 ​ $ 1,265,540 ​ $ 1,265,913 ​ $ 3,261 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 5,459 ​ 5,459 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 18,529 ​ 18,529 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 7,122 ​ 7,122 ​ 19 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 278 ​ 278 ​ — ​ — ​ Consumer and other ​ 3 ​ — ​ 24 ​ 27 ​ 8,165 ​ 8,192 ​ — ​ 24 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 132 ​ $ — ​ $ 268 ​ $ 400 ​ $ 1,305,093 ​ $ 1,305,493 ​ $ 3,280 ​ $ 24 ​ ​
Summary of troubled debt restructurings by class of loan	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of Accrual Number of Nonaccrual ​ (Dollars in thousands) Loans Status Loans Status Total December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 2 ​ $ 414 ​ ​ 2 ​ $ 410 ​ $ 824 Total ​ 2 ​ $ 414 ​ ​ 2 ​ $ 410 ​ $ 824 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 3 ​ $ 551 ​ ​ 1 ​ $ 340 ​ $ 891 Total ​ 3 ​ $ 551 ​ ​ 1 ​ $ 340 ​ $ 891 ​
Summarizes loans in the loan payment deferral program by class of loan	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ ​ ​ December 31, 2021 ​ (Dollars in thousands) ​ Loans in the Loan Payment Deferral Program ​ Percent of Total Loans ​ Loans in the Loan Payment Deferral Program ​ Percent of Total Loans One- to four-family residential mortgage ​ $ 59,948 ​ 4.6 % ​ $ 74,704 ​ 5.7 % Non-residential mortgage ​ ​ 3,220 ​ 0.3 ​ ​ ​ 3,928 ​ 0.3 ​ Total ​ $ 63,168 ​ 4.9 % ​ $ 78,632 ​ 6.0 % ​

Accrued Interest Receivable (Ta

Accrued Interest Receivable (Tables)	12 Months Ended
	Dec. 31, 2022
Accrued Interest Receivable
Schedule of components of accrued interest receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Loans receivable ​ $ 4,595 ​ $ 4,644 ​ Investment securities ​ ​ 1,497 ​ ​ 1,126 ​ Interest-bearing deposits ​ 23 ​ 16 ​ Total ​ $ 6,115 ​ $ 5,786 ​

Interest Rate Lock and Forwar_2

Interest Rate Lock and Forward Loan Sale Commitments (Tables)	12 Months Ended
	Dec. 31, 2022
Interest Rate Lock and Forward Loan Sale Commitments
Schedule of location of assets and liabilities related to derivatives	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Asset Derivatives ​ Liability Derivatives ​ ​ Location on ​ Fair Value at December 31, ​ Fair Value at December 31, (Dollars in thousands) Balance Sheet 2022 2021 2022 2021 Interest rate contracts Prepaid expenses and other assets ​ $ — ​ $ 9 ​ $ — ​ $ — ​ Interest rate contracts Accounts payable and accrued expenses ​ — ​ — ​ — ​ 9 ​ Total derivatives ​ ​ ​ $ — ​ $ 9 ​ $ — ​ $ 9 ​ ​

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2022
Premises and Equipment
Schedule of premises and equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Land ​ $ 585 ​ $ 585 ​ Buildings and improvements ​ 1,400 ​ 1,400 ​ Leasehold improvements ​ 17,949 ​ 14,683 ​ Furniture, fixtures and equipment ​ 6,766 ​ 6,062 ​ Automobiles ​ 130 ​ 118 ​ ​ ​ 26,830 ​ 22,848 ​ Less accumulated depreciation and amortization ​ (19,494) ​ (18,783) ​ ​ ​ 7,336 ​ 4,065 ​ Construction in progress ​ 263 ​ — ​ Total ​ $ 7,599 ​ $ 4,065 ​ ​

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2022
Deposits
Summary of deposit accounts by type with their respective weighted-average interest rates	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2022 ​ 2021 (Dollars in thousands) Amount Rate Amount Rate Non-interest bearing ​ $ 68,095 — % $ 69,980 — % Savings accounts ​ 910,652 0.13 ​ 1,085,255 0.07 ​ Certificates of deposit ​ 429,687 2.67 ​ 225,054 0.85 ​ Money market ​ 5,372 0.10 ​ 5,368 0.10 ​ Checking and Super NOW ​ 302,346 0.02 ​ 296,171 0.02 ​ Total ​ $ 1,716,152 0.74 % $ 1,681,828 0.16 % ​
Schedule of maturity of certificate of deposit accounts	​ ​ ​ ​ ​ ​ Maturing in: ​ ​ 2023 ​ $ 356,940 ​ 2024 ​ 56,679 ​ 2025 ​ 6,264 ​ 2026 ​ 4,360 ​ 2027 ​ 5,444 ​ Total ​ $ 429,687 ​ ​
Schedule of interest expense by type of deposit	​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Savings ​ $ 949 ​ $ 1,074 ​ Certificates of deposit and money market ​ 3,914 ​ 2,845 ​ Checking and Super NOW ​ 62 ​ 56 ​ Total ​ $ 4,925 ​ $ 3,975 ​ ​

Advances from the Federal Hom_2

Advances from the Federal Home Loan Bank (Tables)	12 Months Ended
	Dec. 31, 2022
Advances from the Federal Home Loan Bank
Schedule of advances outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ 2022 ​ 2021 ​ ​ ​ Weighted ​ ​ Weighted ​ ​ ​ Average ​ ​ ​ ​ Average ​ (Dollars in thousands) Amount ​ Rate ​ Amount ​ Rate ​ Due within one year ​ $ 24,000 1.27 % $ — — % Due over 1 year to 2 years ​ ​ 82,000 1.40 ​ ​ 24,000 1.27 ​ Due over 2 years to 3 years ​ 25,000 1.58 ​ 82,000 1.40 ​ Due over 3 years to 4 years ​ ​ 10,000 1.97 ​ 25,000 1.58 ​ Due over 4 years to 5 years ​ — — ​ 10,000 1.97 ​ Total ​ $ 141,000 1.45 % $ 141,000 1.45 %

Securities Sold Under Agreeme_2

Securities Sold Under Agreements to Repurchase (Tables)	12 Months Ended
	Dec. 31, 2022
Securities Sold Under Agreements to Repurchase
Summary of securities sold under agreements to repurchase	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 December 31, 2021 Weighted Weighted Repurchase Average Repurchase Average (Dollars in thousands) Liability Rate Liability Rate Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Over 1 year to 2 years ​ $ 5,000 1.81 % $ — — % Over 2 years to 3 years ​ ​ 5,000 ​ 1.73 ​ ​ 5,000 ​ 1.88 ​ Over 3 years to 4 years ​ — — ​ ​ 5,000 1.73 ​ Total ​ $ 10,000 1.81 % $ 10,000 1.81 % ​
Summary comparing carrying value and fair value of securities pledged to secure repurchase agreements, repurchase liability, and amount at risk	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Carrying Fair Average Value of Value of Repurchase Amount Months to (Dollars in thousands) Securities Securities Liability at Risk Maturity Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Over 90 days ​ $ 13,562 ​ $ 11,351 ​ $ 10,000 ​ $ 3,562 24 ​

Offsetting of Financial Liabi_2

Offsetting of Financial Liabilities (Tables)	12 Months Ended
	Dec. 31, 2022
Offsetting of Financial Liabilities
Schedule of securities sold under agreements to repurchase subject to conditional right of offset	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net Amount of Gross Amount Not Offset in the Gross Amount Gross Amount Liabilities Balance Sheet of Recognized Offset in the Presented in the Financial Cash Collateral (Dollars in thousands) Liabilities Balance Sheet Balance Sheet Instruments ​ Pledged Net Amount December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ —

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Taxes
Schedule of allocation of federal and state income taxes between current and deferred provisions	​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Current ​ ​ ​ ​ ​ ​ ​ Federal ​ $ 2,911 ​ $ 4,466 ​ State ​ 1,317 ​ 1,602 ​ ​ ​ 4,228 ​ 6,068 ​ Deferred ​ ​ ​ ​ ​ ​ ​ Federal ​ 990 ​ 205 ​ State ​ 100 ​ 100 ​ ​ ​ 1,090 ​ 305 ​ Total ​ $ 5,318 ​ $ 6,373 ​ ​
Schedule of reconciliation of tax provision based on statutory corporate rate on pretax income and provision for taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) 2022 2021 Income tax expense at statutory rate ​ $ 4,510 ​ $ 4,999 ​ Income tax effect of: ​ ​ ​ ​ ​ ​ ​ State income taxes, net of federal income tax benefits ​ 1,079 ​ 1,274 ​ Other tax-exempt income ​ (166) ​ (164) ​ Share-based compensation ​ 9 ​ 1 ​ Meal and entertainment expenses ​ ​ 49 ​ ​ 54 ​ Non-deductible executive compensation ​ ​ 119 ​ ​ 127 ​ Recovery on bank-owned life insurance ​ ​ (216) ​ ​ — ​ Other ​ (66) ​ 82 ​ Total income tax expense ​ $ 5,318 ​ $ 6,373 ​ Effective income tax rate ​ 24.76 % 26.78 % ​
Schedule of components of income taxes payable (receivable)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Current taxes (receivable) payable: ​ ​ ​ ​ ​ ​ ​ Federal ​ $ (519) ​ $ 245 ​ State ​ 1,357 ​ 1,618 ​ ​ ​ $ 838 ​ $ 1,863 ​ Deferred taxes (receivable) payable: ​ ​ ​ ​ ​ ​ ​ Federal ​ $ (707) ​ $ (1,112) ​ State ​ (936) ​ (815) ​ ​ ​ $ (1,643) ​ $ (1,927) ​ ​
Schedule of tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Deferred tax assets: ​ ​ ​ ​ ​ ​ ​ Premises and equipment ​ $ — ​ $ 473 ​ Hawaii franchise tax ​ 377 ​ 454 ​ Allowance for loan losses ​ 541 ​ 711 ​ Employee benefit plans ​ 2,714 ​ 2,703 ​ Equity incentive plan ​ 141 ​ 151 ​ Deferred compensation ​ 199 ​ 240 ​ Net lease liability ​ ​ 212 ​ ​ 203 ​ Unrealized loss on securities available for sale ​ ​ 725 ​ ​ — ​ Other ​ 16 ​ 44 ​ ​ ​ 4,925 ​ 4,979 ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ ​ Deferred loan costs ​ 2,601 ​ 2,654 ​ Premises and equipment ​ ​ 254 ​ ​ — ​ FHLB stock dividends ​ 125 ​ 126 ​ Prepaid expense ​ 226 ​ 186 ​ Premiums on loans sold ​ 76 ​ 86 ​ ​ ​ 3,282 ​ 3,052 ​ Net deferred tax assets ​ $ 1,643 ​ $ 1,927 ​ ​

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2022
Employee Benefit Plans
Schedule of status of Pension Plan and SERP	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan ​ SERP ​ ​ December 31, (Dollars in thousands) 2022 2021 2022 2021 Accumulated benefit obligation at end of year ​ $ 15,865 ​ $ 20,943 ​ $ 9,947 ​ $ 9,915 ​ Change in projected benefit obligation: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Benefit obligation at beginning of year ​ $ 20,943 ​ $ 24,130 ​ $ 9,915 ​ $ 9,866 ​ Service cost (income) ​ 118 ​ 105 ​ (135) ​ (111) ​ Interest cost ​ 597 ​ 547 ​ 179 ​ 177 ​ Actuarial gain ​ (4,802) ​ (2,885) ​ — ​ — ​ Benefits paid ​ (990) ​ (954) ​ (11) ​ (17) ​ Benefit obligation at end of year ​ 15,866 ​ 20,943 ​ 9,948 ​ 9,915 ​ Change in plan assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of plan assets at beginning of year ​ 23,125 ​ 21,151 ​ — ​ — ​ Actual return on plan assets ​ (3,799) ​ 2,928 ​ — ​ — ​ Employer contributions ​ — ​ — ​ 11 ​ 17 ​ Benefits paid ​ (990) ​ (954) ​ (11) ​ (17) ​ Fair value of plan assets at end of year ​ 18,336 ​ 23,125 ​ — ​ — ​ Funded status at end of year ​ $ 2,470 ​ $ 2,182 ​ $ (9,948) ​ $ (9,915) ​ Amounts recognized in the Consolidated Balance Sheets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Prepaid expenses and other assets (Accounts payable and accrued expenses) ​ $ 2,470 ​ $ 2,182 ​ $ (9,948) ​ $ (9,915) ​ Amounts recognized in accumulated other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net actuarial loss ​ $ 7,708 ​ $ 7,401 ​ $ — ​ $ — ​ Prior service cost ​ 124 ​ 129 ​ — ​ — ​ Accumulated other comprehensive loss, before tax ​ $ 7,832 ​ $ 7,530 ​ $ — ​ $ — ​ ​
Schedule of changes recognized in accumulated other comprehensive loss for Pension Plan	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan ​ ​ Year Ended December 31, (Dollars in thousands) 2022 2021 Accumulated other comprehensive loss at beginning of year, before tax ​ $ 7,530 ​ $ 12,222 ​ Actuarial net loss (gain) arising during the period ​ 517 ​ (4,372) ​ Amortizations (recognized in net periodic benefit cost): ​ ​ ​ ​ ​ ​ ​ Actuarial loss ​ (210) ​ (315) ​ Prior service cost ​ (5) ​ (5) ​ Total recognized in other comprehensive loss ​ 302 ​ (4,692) ​ Accumulated other comprehensive loss at end of year, before tax ​ $ 7,832 ​ $ 7,530 ​ ​
Schedule of weighted average assumptions used to determine benefit obligations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan ​ SERP ​ ​ Year Ended December 31, ​ 2022 2021 2022 2021 Assumptions used to determine the year-end benefit obligations: ​ ​ ​ ​ ​ ​ ​ ​ ​ Discount rate 5.40 % 2.90 % 5.00 % 5.00 % Rate of compensation increase N/A ​ N/A ​ 5.00 % 5.00 % ​
Schedule of Pension Plan's assets measured at fair value	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of Measurements at Report Date Using: ​ ​ ​ ​ ​ Quoted Prices ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ in Active ​ Significant ​ ​ ​ ​ ​ ​ ​ ​ Markets for ​ Other ​ Significant ​ ​ ​ ​ ​ Identical ​ Observable ​ Unobservable ​ ​ Total Fair ​ Assets ​ Inputs ​ Inputs (Dollars in thousands) ​ Value ​ (Level 1) ​ (Level 2) ​ (Level 3) December 31, 2022: ​ ​ ​ ​ ​ Cash ​ $ 1,452 ​ $ 1,452 ​ $ — ​ $ — ​ Equities ​ 11,659 ​ 11,659 ​ — ​ — ​ Mutual funds (1) ​ 5,225 ​ 5,225 ​ — ​ — ​ Total ​ $ 18,336 ​ $ 18,336 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 1,017 ​ $ 1,017 ​ $ — ​ $ — ​ Equities ​ 16,276 ​ 16,276 ​ — ​ — ​ Mutual funds (1) ​ 5,832 ​ 5,832 ​ — ​ — ​ Total ​ $ 23,125 ​ $ 23,125 ​ $ — ​ $ — ​ (1) This category includes mutual funds that invest in equities and bonds. The mutual fund managers have the ability to change the amounts invested in equities and bonds depending on their investment outlook. ​
Schedule of estimated future benefit payments reflecting expected future service	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension ​ ​ (Dollars in thousands) ​ Plan ​ SERP 2023 ​ $ 998 ​ $ — ​ 2024 ​ 1,016 ​ 8,733 ​ 2025 ​ 1,153 ​ 125 ​ 2026 ​ 1,216 ​ 125 ​ 2027 ​ 1,233 ​ 125 ​ 2028 - 2032 ​ 6,166 ​ 624 ​ Total ​ $ 11,782 ​ $ 9,732 ​ ​
Schedule of weighted average assumptions used to determine net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan SERP ​ ​ Year Ended December 31, ​ 2022 2021 2022 2021 Assumptions used to determine the net periodic benefit cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ Discount rate 2.90 % 2.50 % 5.00 % 5.03 % Expected return on plan assets 6.75 ​ 7.00 ​ - ​ - ​ Rate of compensation increase N/A ​ N/A ​ 5.00 ​ 5.00 ​ ​
Schedule of components of net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension Plan SERP ​ ​ Year Ended December 31, ​ (Dollars in thousands) 2022 2021 2022 2021 Net periodic benefit (income) cost for the year: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service cost (income) ​ $ 118 ​ $ 105 ​ $ (135) ​ $ (111) ​ Interest cost ​ 597 ​ 547 ​ 179 ​ 177 ​ Expected return on plan assets ​ (1,520) ​ (1,441) ​ — ​ — ​ Amortization of prior service cost ​ 5 ​ 5 ​ — ​ — ​ Recognized actuarial loss ​ 210 ​ 315 ​ — ​ — ​ Recognized curtailment loss ​ — ​ — ​ — ​ — ​ Net periodic benefit (income) cost for the year: ​ $ (590) ​ $ (469) ​ $ 44 ​ $ 66 ​ ​

Employee Stock Ownership Plan (

Employee Stock Ownership Plan (Tables)	12 Months Ended
	Dec. 31, 2022
Employee Stock Ownership Plan.
Schedule of shares held by the ESOP trust	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, 2022 2021 Allocated shares ​ 583,474 ​ 540,869 ​ ​ Unearned shares ​ 293,598 ​ 342,531 ​ ​ Total ESOP shares ​ 877,072 ​ 883,400 ​ ​ Fair value of unearned shares, in thousands ​ $ 7,049 ​ $ 8,649 ​ ​ ​

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2022
Schedule of compensation expense and related tax benefit for all share-based awards	​ ​ ​ ​ ​ ​ ​ ​ ​ (In thousands) 2022 2021 Compensation expense ​ $ 480 ​ $ 351 ​ Income tax benefit ​ 131 ​ 96 ​ ​
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Aggregate Average Remaining Intrinsic Exercise Contractual Value Options Price Life (years) (in thousands) Options outstanding at December 31, 2020 3,085 ​ $ 23.62 1.67 ​ $ 1 ​ Granted — ​ — — ​ — ​ Exercised — ​ — — ​ — ​ Forfeited — ​ — — ​ — ​ Expired — ​ — — ​ — ​ Options outstanding at December 31, 2021 3,085 ​ $ 23.62 0.67 ​ $ 5 ​ Granted — ​ — — ​ — ​ Exercised — ​ — — ​ — ​ Forfeited — ​ — — ​ — ​ Expired 3,085 ​ — — ​ — ​ Options outstanding at December 31, 2022 — ​ $ — — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options vested and exercisable at December 31, 2022 — ​ $ — — ​ $ — ​ ​
Restricted Stock
Schedule of restricted stock award activity	​ ​ ​ ​ ​ ​ ​ ​ Weighted Average Grant Restricted Date Fair Stock Value Unvested at December 31, 2020 ​ 23,695 ​ $ 24.24 ​ Granted 10,849 ​ 26.67 ​ Vested 11,336 ​ 25.81 ​ Forfeited — ​ — ​ Unvested at December 31, 2021 23,208 ​ $ 24.61 ​ Granted 12,013 ​ 23.77 ​ Vested 11,557 ​ 24.68 ​ Forfeited — ​ — ​ Unvested at December 31, 2022 23,664 ​ $ 24.15 ​ ​
Restricted Stock Units Based on a Performance Condition
Schedule of restricted stock award activity	​ ​ ​ ​ ​ ​ ​ Performance- ​ ​ ​ ​ Based Restricted ​ ​ ​ Stock Units Weighted ​ ​ Based on a ​ Average Grant ​ ​ Performance ​ Date Fair Condition Value Unvested at December 31, 2020 40,585 ​ $ 25.83 Granted 13,016 ​ 26.67 Vested 7,473 ​ 30.73 Forfeited 4,545 ​ 30.73 Unvested at December 31, 2021 41,583 ​ $ 24.68 Granted 14,412 ​ 23.77 Vested 7,670 ​ 27.30 Forfeited 4,768 ​ 27.30 Unvested at December 31, 2022 43,557 ​ $ 23.63 ​
Restricted Stock Units Based on a Market Condition
Schedule of restricted stock award activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Performance- ​ ​ ​ ​ ​ Based Restricted ​ Monte Carlo ​ ​ Stock Units ​ Valuation of ​ ​ Based on a ​ the Company's Market Condition Stock Unvested at December 31, 2020 10,147 ​ $ 24.69 Granted 3,254 ​ 25.94 Vested 1,628 ​ 28.32 Forfeited 1,377 ​ 28.32 Unvested at December 31, 2021 10,396 ​ $ 24.03 Granted 3,603 ​ 24.42 Vested — ​ — Forfeited 3,110 ​ 24.45 Unvested at December 31, 2022 10,889 ​ $ 24.04 ​

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2022
Earnings Per Share
Schedule of information used to compute basic and diluted earnings per share	​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, (Dollars in thousands, except per share data) 2022 2021 Net income ​ $ 16,156 ​ $ 17,430 ​ Income allocated to participating securities ​ ​ (98) ​ ​ (75) ​ Net income available to common shareholders ​ $ 16,058 ​ $ 17,355 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average number of shares used in: ​ ​ ​ ​ ​ ​ ​ Basic earnings per share ​ 8,865,946 ​ 9,059,204 ​ Dilutive common stock equivalents: ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ 54,768 ​ 51,131 ​ Diluted earnings per share ​ 8,920,714 ​ 9,110,335 ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income per common share, basic ​ $ 1.81 ​ $ 1.92 ​ Net income per common share, diluted ​ $ 1.80 ​ $ 1.90 ​

Other Comprehensive Loss (Table

Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2022
Other Comprehensive Loss
Schedule of changes in components of accumulated other comprehensive loss, net of taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unfunded Unrealized Pension (Gain)/Loss on (Dollars in thousands) Liability Securities Total December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of year ​ $ 5,524 ​ $ — ​ $ 5,524 ​ Other comprehensive loss, net of taxes ​ 222 ​ 1,998 ​ 2,220 ​ Net current period other comprehensive loss ​ 222 ​ 1,998 ​ 2,220 ​ Balances at end of year ​ $ 5,746 ​ $ 1,998 ​ $ 7,744 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of year ​ $ 8,967 ​ $ (276) ​ $ 8,691 ​ Other comprehensive (income) loss, net of taxes ​ (3,443) ​ 3 ​ (3,440) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 273 ​ 273 ​ Net current period other comprehensive (income) loss ​ (3,443) ​ 276 ​ (3,167) ​ Balances at end of year ​ $ 5,524 ​ $ — ​ $ 5,524 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of tax effect on each component of accumulated other comprehensive loss	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, 2022 ​ 2021 Pretax ​ ​ After Tax Pretax ​ ​ After Tax (Dollars in thousands) Amount ​ Tax ​ Amount ​ Amount ​ Tax ​ Amount Unfunded pension liability ​ $ 302 ​ $ (80) ​ $ 222 ​ $ (4,692) ​ $ 1,249 ​ $ (3,443) ​ Unrealized loss on securities ​ 2,723 ​ (725) ​ 1,998 ​ 4 ​ (1) ​ 3 ​ Amount reclassified from other comprehensive income ​ — ​ — ​ — ​ 373 ​ (100) ​ 273 ​ Total ​ $ 3,025 ​ $ (805) ​ $ 2,220 ​ $ (4,315) ​ $ 1,148 ​ $ (3,167) ​

Regulatory Capital and Superv_2

Regulatory Capital and Supervision (Tables)	12 Months Ended
	Dec. 31, 2022
Regulatory Capital and Supervision
Schedule of regulatory capital ratios	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Required Ratio ​ Actual Amount Actual Ratio December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ Tier 1 Leverage Capital ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 5.00 % $ 235,408 ​ 10.87 % Territorial Bancorp Inc. ​ ​ $ 264,295 ​ 12.21 % Common Equity Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 9.00 % $ 235,408 ​ 25.98 % Territorial Bancorp Inc. ​ ​ $ 264,295 ​ 29.16 % Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 10.50 % $ 235,408 ​ 25.98 % Territorial Bancorp Inc. ​ ​ $ 264,295 ​ 29.16 % Total Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 12.50 % $ 237,488 ​ 26.20 % Territorial Bancorp Inc. ​ ​ $ 266,375 ​ 29.39 % ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ Tier 1 Leverage Capital ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 5.00 % $ 235,785 ​ 11.09 % Territorial Bancorp Inc. ​ ​ $ 261,846 ​ 12.31 % Common Equity Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 9.00 % $ 235,785 ​ 26.47 % Territorial Bancorp Inc. ​ ​ $ 261,846 ​ 29.40 % Tier 1 Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 10.50 % $ 235,785 ​ 26.47 % Territorial Bancorp Inc. ​ ​ $ 261,846 ​ 29.40 % Total Risk-Based Capital (1) ​ ​ ​ ​ ​ ​ ​ ​ Territorial Savings Bank 12.50 % $ 238,515 ​ 26.78 % Territorial Bancorp Inc. ​ ​ $ 264,576 ​ 29.70 % (1) The required Common Equity Tier 1 Risk-Based Capital, Tier 1 Risk-Based Capital and Total Risk-Based Capital ratios are based on the fully-phased in capital ratios in the Basel III capital regulations plus the 2.50% capital conservation buffer. ​

Revenue Recognition (Tables)

Revenue Recognition (Tables)	12 Months Ended
	Dec. 31, 2022
Revenue Recognition
Reconciliation of revenue from contracts with customers and other revenue reported in line items	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service and ​ ​ ​ ​ (Dollars in thousands) Other Fees Other Total Year ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 1,276 ​ $ 221 ​ $ 1,497 Other revenue ​ ​ 140 ​ ​ 1,783 ​ ​ 1,923 Total ​ $ 1,416 ​ $ 2,004 ​ $ 3,420 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 2,330 ​ $ 177 ​ $ 2,507 Other revenue ​ ​ 133 ​ ​ 550 ​ ​ 683 Total ​ $ 2,463 ​ $ 727 ​ $ 3,190

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2022
Leases
Schedule of lease costs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended ​ December 31, (Dollars in thousands) 2022 2021 Lease costs: ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 2,991 ​ $ 3,398 ​ Short-term lease costs ​ 296 ​ 47 ​ Variable lease costs ​ 165 ​ 156 ​ Total lease costs ​ $ 3,452 ​ $ 3,601 ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ $ 3,193 ​ $ 3,372 ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 7,462 ​ $ 4,060 ​ ​
Schedule of future minimum rental commitments under noncancellable operating leases and lease payment obligations	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ 2023 ​ $ 2,894 ​ ​ ​ ​ ​ ​ 2024 ​ 2,757 ​ ​ ​ ​ ​ ​ 2025 ​ 2,137 ​ ​ ​ ​ ​ ​ 2026 ​ 1,974 ​ ​ ​ ​ ​ ​ 2027 ​ 1,896 ​ ​ ​ ​ ​ ​ Thereafter ​ 10,995 ​ ​ ​ ​ ​ ​ Total ​ ​ 22,653 ​ ​ ​ ​ ​ ​ Less lease incentives to be received in 2023 ​ ​ (4,996) ​ ​ ​ ​ ​ ​ Less present value discount ​ ​ (2,362) ​ ​ ​ ​ ​ ​ Present value of leases ​ $ 15,295 ​ ​ ​ ​ ​ ​ ​
Schedule of other lease related information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ December 31, ​ ​ ​ 2022 ​ 2021 ​ Weighted-average remaining lease term (years) ​ 8.88 ​ ​ 5.93 ​ ​ Weighted-average discount rate ​ ​ 2.03 % ​ ​ 1.83 % ​ ​

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2022
Fair Value
Schedule of estimated fair values of financial instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ ​ Fair Value Measurements Using (Dollars in thousands) Amount Fair Value Level 1 Level 2 Level 3 December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 40,553 ​ $ 40,553 ​ $ 40,553 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 20,821 ​ ​ 20,821 ​ ​ — ​ ​ 20,821 ​ ​ — ​ Investment securities held to maturity ​ 717,773 ​ ​ 591,084 ​ ​ — ​ ​ 591,084 ​ ​ — ​ Loans receivable, net ​ 1,294,764 ​ ​ 1,180,840 ​ ​ — ​ ​ — ​ ​ 1,180,840 ​ FHLB stock ​ 8,197 ​ ​ 8,197 ​ ​ — ​ ​ 8,197 ​ ​ — ​ FRB stock ​ ​ 3,170 ​ ​ 3,170 ​ ​ — ​ ​ 3,170 ​ ​ — ​ Accrued interest receivable ​ 6,115 ​ ​ 6,115 ​ ​ 23 ​ ​ 1,497 ​ ​ 4,595 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,716,152 ​ ​ 1,708,612 ​ ​ — ​ ​ 1,286,465 ​ ​ 422,147 ​ Advances from the Federal Home Loan Bank ​ 141,000 ​ ​ 133,145 ​ ​ — ​ ​ 133,145 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,440 ​ ​ — ​ ​ 9,440 ​ ​ — ​ Accrued interest payable ​ 701 ​ ​ 701 ​ ​ — ​ ​ 33 ​ ​ 668 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 99,859 ​ $ 99,859 ​ $ 99,859 ​ $ — ​ $ — ​ Investment securities held to maturity ​ 636,442 ​ ​ 634,987 ​ ​ — ​ ​ 634,987 ​ ​ — ​ Loans receivable, net ​ 1,302,824 ​ ​ 1,314,609 ​ ​ — ​ ​ — ​ ​ 1,314,609 ​ FHLB stock ​ 8,173 ​ ​ 8,173 ​ ​ — ​ ​ 8,173 ​ ​ — ​ FRB stock ​ ​ 3,158 ​ ​ 3,158 ​ ​ — ​ ​ 3,158 ​ ​ — ​ Accrued interest receivable ​ 5,786 ​ ​ 5,786 ​ ​ 16 ​ ​ 1,126 ​ ​ 4,644 ​ Interest rate contracts ​ 9 ​ ​ 9 ​ ​ — ​ ​ 9 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,681,828 ​ ​ 1,682,078 ​ ​ — ​ ​ 1,456,773 ​ ​ 225,305 ​ Advances from the Federal Home Loan Bank ​ 141,000 ​ ​ 141,867 ​ ​ — ​ ​ 141,867 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 10,143 ​ ​ — ​ ​ 10,143 ​ ​ — ​ Accrued interest payable ​ 35 ​ ​ 35 ​ ​ — ​ ​ 34 ​ ​ 1 ​ Interest rate contracts ​ 9 ​ ​ 9 ​ ​ — ​ ​ 9 ​ ​ — ​ ​
Schedule of assets and liabilities measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Level 1 Level 2 Level 3 Total ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment securities available for sale ​ $ — ​ $ 20,821 ​ $ — ​ $ 20,821 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts — assets ​ $ — ​ $ 9 ​ $ — ​ $ 9 ​ Interest rate contracts — liabilities ​ — ​ (9) ​ — ​ (9) ​ ​ There were no assets or liabilities measured at fair value on a nonrecurring basis as of December 31, 2022 or 2021.

Parent Company Only (Tables)

Parent Company Only (Tables)	12 Months Ended
	Dec. 31, 2022
Parent Company Only
Condensed Balance Sheets	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, (Dollars in thousands) 2022 2021 Assets ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 28,515 ​ $ 25,532 ​ Investment in Territorial Savings Bank ​ 227,663 ​ 230,261 ​ Receivable from Territorial Savings Bank ​ 408 ​ 566 ​ Prepaid expenses and other assets ​ 105 ​ 132 ​ Total assets ​ $ 256,691 ​ $ 256,491 ​ Liabilities and Equity ​ ​ ​ ​ ​ ​ ​ Other liabilities ​ $ 141 ​ $ 170 ​ Equity ​ 256,550 ​ 256,321 ​ Total liabilities and equity ​ $ 256,691 ​ $ 256,491 ​ ​
Condensed Statements of Income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, (Dollars in thousands) 2022 2021 Interest and dividend income: ​ ​ ​ ​ ​ ​ ​ Dividends from Territorial Savings Bank ​ $ 17,500 ​ $ 22,000 ​ Interest-earning deposit with Territorial Savings Bank ​ 4 ​ 5 ​ Total interest and dividend income ​ 17,504 ​ 22,005 ​ ​ ​ ​ ​ ​ ​ ​ ​ Noninterest expense: ​ ​ ​ ​ ​ ​ ​ Salaries ​ 42 ​ 43 ​ Other general and administrative expenses ​ 656 ​ 998 ​ Total noninterest expense ​ 698 ​ 1,041 ​ ​ ​ ​ ​ ​ ​ ​ ​ Income before income taxes and equity in undistributed earnings in subsidiaries ​ 16,806 ​ 20,964 ​ Income taxes ​ (209) ​ (288) ​ Income before equity in undistributed earnings in subsidiaries ​ 17,015 ​ 21,252 ​ Equity in undistributed earnings of Territorial Savings Bank, net of dividends ​ (859) ​ (3,822) ​ Net income ​ $ 16,156 ​ $ 17,430 ​ ​
Condensed Statements of Cash Flows	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, (Dollars in thousands) 2022 2021 Cash flows from operating activities: ​ ​ ​ ​ ​ ​ ​ Net income ​ $ 16,156 ​ $ 17,430 ​ Adjustments to reconcile net income to net cash provided by operating activities: ​ ​ ​ ​ ​ ​ ​ Equity in undistributed earnings of Territorial Savings Bank, net of dividends ​ 859 ​ 3,822 ​ Net decrease in prepaid expenses and other assets ​ 1,275 ​ 1,762 ​ Net decrease in other liabilities ​ (263) ​ (366) ​ Net cash provided by operating activities ​ 18,027 ​ 22,648 ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash flows from investing activities: ​ ​ ​ ​ ​ ​ ​ Investment in Territorial Savings Bank ​ — ​ — ​ Net cash used in investing activities ​ — ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash flows from financing activities: ​ ​ ​ ​ ​ ​ ​ Repurchases of common stock ​ (5,973) ​ (5,000) ​ Cash dividends paid ​ (9,071) ​ (10,224) ​ Net cash used in financing activities ​ (15,044) ​ (15,224) ​ Net increase in cash ​ 2,983 ​ 7,424 ​ Cash at beginning of the period ​ 25,532 ​ 18,108 ​ Cash at end of the period ​ $ 28,515 ​ $ 25,532 ​

Organization - Narrative (Detai

Organization - Narrative (Details)	12 Months Ended
	Dec. 31, 2022 subsidiary
Organization
Number of inactive subsidiaries	1

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Description of Business, Investment Securities and Transfer of Financial Assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) item
Description of Business
Number of branches located throughout Hawaii | item	29
Investment Securities
Investment securities available for sale, at fair value | $	$ 20,821
Transfer of financial assets
Percentage of receipt on transfer of mortgage-backed securities issued	100%

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Premises and Equipment Useful Lives (Details)	12 Months Ended
	Dec. 31, 2022
Buildings and improvements
Premises and equipment
Estimated useful life	30 years
Furniture, fixtures and equipment | Minimum
Premises and equipment
Estimated useful life	3 years
Furniture, fixtures and equipment | Maximum
Premises and equipment
Estimated useful life	10 years
Automobiles
Premises and equipment
Estimated useful life	3 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Common Stock Repurchase Program and Forms of Outstanding Common Stock (Details)	12 Months Ended
	Dec. 31, 2022 security $ / shares shares	Dec. 31, 2021 $ / shares shares
Common stock
Number of different forms of outstanding common stock | security	2
Common Stock Repurchase Program
Common Stock Repurchase Program
Repurchase of shares of common stock (in shares) | shares	262,621	198,773
Average cost of shares repurchased (in dollars per share) | $ / shares	$ 22.75	$ 25.15

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Bank-Owned Life Insurance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Bank-Owned Life Insurance
Percentage applied on Tier 1 capital plus allowance for loan losses to calculate ceiling limit of investment	25%
Amount of ceiling limit of investment	$ 59,400
Amount of investment in bank-owned life insurance	$ 47,783	$ 51,423

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Recently Issued Accounting Pronouncement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Basis of Presentation
Right-of-use asset, net	$ 14,498	$ 9,982
Lease liability	15,295	$ 10,744
Increase in allowance for credit losses	4,000
Allowance for credit losses	$ 6,000

Cash and Cash Equivalents (Deta

Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents
Cash and due from banks	$ 9,722	$ 11,662
Interest-earning deposits in other banks	30,831	88,197
Cash and cash equivalents	$ 40,553	$ 99,859

Investment Securities - Amortiz

Investment Securities - Amortized Cost and Fair Values of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Available-for-Sale [Abstract]
Amortized Cost	$ 23,544
Estimated Fair Value	20,821
Debt Securities, Held-to-Maturity, Maturity [Abstract]
Amortized Cost	717,773	$ 636,442
Estimated Fair Value	591,084	634,987
U.S. government-sponsored mortgage-backed securities
Available-for-Sale [Abstract]
Amortized Cost	23,544
Gross Unrealized Losses	(2,723)
Estimated Fair Value	20,821
Debt Securities, Held-to-Maturity, Maturity [Abstract]
Amortized Cost	717,773	636,442
Gross Unrealized Gains	62	5,699
Gross Unrealized Losses	(126,751)	(7,154)
Estimated Fair Value	$ 591,084	$ 634,987

Investment Securities - Maturit

Investment Securities - Maturity Schedule of Available-for-Sale Securities (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Amortized Cost
Due after 10 years	$ 23,544
Amortized Cost	23,544
Estimated Fair Value
Due after 10 years	20,821
Estimated Fair Value	20,821
U.S. government-sponsored mortgage-backed securities
Amortized Cost
Amortized Cost	23,544
Estimated Fair Value
Estimated Fair Value	$ 20,821

Investment Securities - Matur_2

Investment Securities - Maturity Schedule of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Held-to-maturity, Amortized Cost
Due within 5 years	$ 19
Due after 5 years through 10 years	12
Due after 10 years	717,742
Amortized Cost	717,773	$ 636,442
Held-to-maturity, Estimated Fair Value
Due within 5 years	18
Due after 5 years through 10 years	12
Due after 10 years	591,054
Estimated Fair Value	$ 591,084	$ 634,987

Investment Securities - Realize

Investment Securities - Realized Gains and Losses and Proceeds from Sales (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales		$ 26,900,000
Gross gains		1,840,000
Proceeds from sales		23,570,000
U.S. government-sponsored mortgage-backed securities
Realized gains and losses and the proceeds from sales of securities
Gain on held to maturity securities		1,500,000
Available-for-sale mortgage-backed securities sold	$ 0	3,000,000
Debt Securities, Available-for-sale, Realized Gain		339,000
U.S. government-sponsored mortgage-backed securities
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales	$ 0	$ 22,100,000
Minimum | U.S. government-sponsored mortgage-backed securities
Realized gains and losses and the proceeds from sales of securities
Portion of outstanding purchased principal already collected	85%

Investment Securities - Securit

Investment Securities - Securities Pledged (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Realized gains and losses and the proceeds from sales of securities
Amortized cost	$ 717,773	$ 636,442
Debt Securities, Held-to-Maturity, Pledged Status [Extensible Enumeration]	Asset Pledged as Collateral with Right [Member]
Debt Securities, Held-to-Maturity, Pledging Purpose [Extensible Enumeration]		Amortized cost
Asset Pledged as Collateral with Right [Member]
Realized gains and losses and the proceeds from sales of securities
Amortized cost	$ 272,800	$ 140,600

Investment Securities - Held-to

Investment Securities - Held-to-Maturity Unrealized Loss Position Summary (Details) $ in Thousands	Dec. 31, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
U.S. government-sponsored mortgage-backed securities
Investment Securities
Less Than 12 Months Fair Value	$ 20,821
Less Than 12 Months Unrealized Losses	$ (2,723)
Total Number of Securities | security	4
Total Fair Value	$ 20,821
Total Unrealized Losses	(2,723)
U.S. government-sponsored mortgage-backed securities
Investment Securities
Less Than 12 Months Fair Value	210,128	$ 482,629
Less Than 12 Months Unrealized Losses	(22,209)	(6,976)
12 Months or Longer Fair Value	377,418	3,681
12 Months or Longer Unrealized Losses	$ (104,542)	$ (178)
Total Number of Securities | security	148	43
Total Fair Value	$ 587,546	$ 486,310
Total Unrealized Losses	$ (126,751)	$ (7,154)

Federal Home Loan Bank Stock (D

Federal Home Loan Bank Stock (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Federal Home Loan Bank Stock
Capital stock of the FHLB owned	$ 8,197	$ 8,173
Territorial Savings Bank
Federal Home Loan Bank Stock
Capital stock of the FHLB owned	$ 8,200

Federal Reserve Bank Stock (Det

Federal Reserve Bank Stock (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2022
Federal Reserve Bank Stock
Capital stock of the Federal Reserve Bank owned	$ 3,158	$ 3,170
Territorial Savings Bank
Federal Reserve Bank Stock
Requirement to hold shares of capital stock of the Federal Reserve Bank as a percentage of capital and surplus (as a percent)	6%
Capital stock of the Federal Reserve Bank owned	$ 3,200

Loans Receivable and Allowanc_3

Loans Receivable and Allowance for Loan Losses - Components (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loans receivable
Less: Net unearned fees and discounts	$ (2,136)	$ (1,693)
Less: Allowance for loan losses	(2,032)	(2,669)	$ (4,262)
Total unearned fees, discounts and allowance for loan losses	(4,168)	(4,362)
Loans receivable, net	1,294,764	1,302,824
Construction, Commercial and Other Mortgage Loans
Loans receivable
Less: Allowance for loan losses	(434)	(435)	(406)
Home Equity Loans and Lines of Credit.
Loans receivable
Less: Allowance for loan losses	(1)	(1)	(1)
Consumer and other
Loans receivable
Less: Allowance for loan losses	(75)	(89)	(146)
Unallocated
Loans receivable
Less: Allowance for loan losses	(259)	(330)	$ (607)
Real estate loans
Loans receivable
Loans receivable, net	1,290,335	1,298,716
Real estate loans | One- to four-family residential
Loans receivable
Loans receivable, net	1,253,558	1,267,537
Real estate loans | Multi-family residential
Loans receivable
Loans receivable, net	6,448	5,468
Real estate loans | Construction, Commercial and Other Mortgage Loans
Loans receivable
Loans receivable, net	23,903	18,590
Real estate loans | Home Equity Loans and Lines of Credit.
Loans receivable
Loans receivable, net	6,426	7,121
Other loans
Loans receivable
Loans receivable, net	8,597	8,470
Other loans | Loans on Deposit Accounts
Loans receivable
Loans receivable, net	216	278
Other loans | Consumer and other
Loans receivable
Loans receivable, net	$ 8,381	$ 8,192

Loans Receivable and Allowanc_4

Loans Receivable and Allowance for Loan Losses - Activity in Allowance for Loan Losses by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Activity in allowance for loan losses
Balance, beginning of period	$ 2,669	$ 4,262
(Reversal of provision) provision for loan losses	(576)	(1,592)
Allowance for loan losses on loans receivable after provision (reversal of allowance)	2,093	2,670
Charge-offs	(62)	(22)
Recoveries	1	21
Net recoveries (charge-offs)	(61)	(1)
Balance, end of period	$ 2,032	2,669
Look back period to calculate historical loss of each segment	7 years
Residential Mortgage
Activity in allowance for loan losses
Balance, beginning of period	$ 1,814	3,102
(Reversal of provision) provision for loan losses	(551)	(1,305)
Allowance for loan losses on loans receivable after provision (reversal of allowance)	1,263	1,797
Recoveries		17
Net recoveries (charge-offs)		17
Balance, end of period	1,263	1,814
Construction, Commercial and Other Mortgage Loans
Activity in allowance for loan losses
Balance, beginning of period	435	406
(Reversal of provision) provision for loan losses	(1)	29
Allowance for loan losses on loans receivable after provision (reversal of allowance)	434	435
Balance, end of period	434	435
Home Equity Loans and Lines of Credit.
Activity in allowance for loan losses
Balance, beginning of period	1	1
Allowance for loan losses on loans receivable after provision (reversal of allowance)	1	1
Balance, end of period	1	1
Consumer and other
Activity in allowance for loan losses
Balance, beginning of period	89	146
(Reversal of provision) provision for loan losses	47	(39)
Allowance for loan losses on loans receivable after provision (reversal of allowance)	136	107
Charge-offs	(62)	(22)
Recoveries	1	4
Net recoveries (charge-offs)	(61)	(18)
Balance, end of period	75	89
Unallocated
Activity in allowance for loan losses
Balance, beginning of period	330	607
(Reversal of provision) provision for loan losses	(71)	(277)
Allowance for loan losses on loans receivable after provision (reversal of allowance)	259	330
Balance, end of period	$ 259	$ 330

Loans Receivable and Allowanc_5

Loans Receivable and Allowance for Loan Losses - Allowance for Loan Losses and Loans, Net of Unearned Fees and Discounts, by Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Allowance for loan losses:
Collectively evaluated for impairment	$ 2,032	$ 2,669
Total ending allowance balance	2,032	2,669	$ 4,262
Loans:
Individually evaluated for impairment	2,715	3,831
Collectively evaluated for impairment	1,294,081	1,301,662
Total ending loan balance	1,296,796	1,305,493
Residential Mortgage
Allowance for loan losses:
Collectively evaluated for impairment	1,263	1,814
Total ending allowance balance	1,263	1,814	3,102
Loans:
Individually evaluated for impairment	2,693	3,812
Collectively evaluated for impairment	1,255,300	1,267,560
Total ending loan balance	1,257,993	1,271,372
Construction, Commercial and Other Mortgage Loans
Allowance for loan losses:
Collectively evaluated for impairment	434	435
Total ending allowance balance	434	435	406
Loans:
Collectively evaluated for impairment	23,775	18,529
Total ending loan balance	23,775	18,529
Home Equity Loans and Lines of Credit.
Allowance for loan losses:
Collectively evaluated for impairment	1	1
Total ending allowance balance	1	1	1
Loans:
Individually evaluated for impairment	16	19
Collectively evaluated for impairment	6,411	7,103
Total ending loan balance	6,427	7,122
Consumer and other
Allowance for loan losses:
Collectively evaluated for impairment	75	89
Total ending allowance balance	75	89	146
Loans:
Collectively evaluated for impairment	8,595	8,470
Total ending loan balance	8,595	8,470
Unallocated
Allowance for loan losses:
Collectively evaluated for impairment	259	330
Total ending allowance balance	259	$ 330	$ 607
Loans:
Individually evaluated for impairment	6
Total ending loan balance	$ 6

Loans Receivable and Allowanc_6

Loans Receivable and Allowance for Loan Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Impaired loans
Recorded Investment	$ 2,715	$ 3,831
Unpaid Principal Balance	3,245	4,330
Average Recorded Investment	2,799	3,909
Interest Income Recognized	24	36
One- to four-family residential
Impaired loans
Recorded Investment	2,693	3,812
Unpaid Principal Balance	3,209	4,299
Average Recorded Investment	2,776	3,888
Interest Income Recognized	24	36
Home Equity Loans and Lines of Credit
Impaired loans
Recorded Investment	16	19
Unpaid Principal Balance	30	31
Average Recorded Investment	17	$ 21
Consumer and other
Impaired loans
Recorded Investment	6
Unpaid Principal Balance	6
Average Recorded Investment	$ 6

Loans Receivable and Allowanc_7

Loans Receivable and Allowance for Loan Losses - Delinquent and Nonaccrual Loans (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable
Loans individually evaluated for impairment with a related allowance for loan loss	$ 0	$ 0
Number of nonaccrual loans | loan	15	10
Nonaccrual Loans	$ 2,301,000	$ 3,280,000	$ 3,300,000
Loan delinquency period that may result in loss	90 days
Loan delinquency period after which an appraisal is obtained of the underlying collateral	4 months
Loans 90 Days or More Past Due and Still Accruing		$ 24,000
Consumer and other
Accounts, Notes, Loans and Financing Receivable
Number of nonaccrual loans | loan		2
Loans 90 Days or More Past Due and Still Accruing		$ 24,000

Loans Receivable and Allowanc_8

Loans Receivable and Allowance for Loan Losses - Aging of Loans and Accrual Status by Class (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due
Total Loans	$ 1,296,796	$ 1,305,493
Nonaccrual Loans	2,301	3,280	$ 3,300
Loans 90 Days or More Past Due and Still Accruing		24
One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	1,251,554	1,265,913
Nonaccrual Loans	2,279	3,261
Multi-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	6,439	5,459
Construction, Commercial and Other Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans	23,775	18,529
Home Equity Loans and Lines of Credit
Financing Receivable, Recorded Investment, Past Due
Total Loans	6,427	7,122
Nonaccrual Loans	16	19
Loans on Deposit Accounts
Financing Receivable, Recorded Investment, Past Due
Total Loans	217	278
Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	8,384	8,192
Nonaccrual Loans	6
Loans 90 Days or More Past Due and Still Accruing		24
Not Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	1,295,816	1,305,093
Not Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	1,250,586	1,265,540
Not Past Due | Multi-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	6,439	5,459
Not Past Due | Construction, Commercial and Other Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans	23,775	18,529
Not Past Due | Home Equity Loans and Lines of Credit
Financing Receivable, Recorded Investment, Past Due
Total Loans	6,427	7,122
Not Past Due | Loans on Deposit Accounts
Financing Receivable, Recorded Investment, Past Due
Total Loans	217	278
Not Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	8,372	8,165
Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	980	400
Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	968	373
Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	12	27
30 - 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	6	132
30 - 59 Days Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans		129
30 - 59 Days Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	6	3
60 - 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	409
60 - 89 Days Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	409
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	565	268
90 Days or More Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	559	244
90 Days or More Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	$ 6	$ 24

Loans Receivable and Allowanc_9

Loans Receivable and Allowance for Loan Losses - Troubled Debt Restructurings (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan
Troubled debt restructurings
Troubled debt restructurings	$ 824,000	$ 891,000
Additional disclosures
Real estate owned	$ 0	$ 0
Percentage of current loan balance to the current tax-assessed value of the property securing mortgage loans COVID-19	49.40%
Percentage of current loan balance to current tax	42.50%
Accrual Status
Troubled debt restructurings
Number of Loans | loan	2	3
Troubled debt restructurings	$ 414,000	$ 551,000
Non Accrual Loans
Troubled debt restructurings
Number of Loans | loan	2	1
Troubled debt restructurings	$ 410,000	$ 340,000
Loans modified in troubled debt restructuring
Troubled debt restructurings
Number of Loans | loan	0	0
Number of loans subsequently defaulted | loan	0
Additional disclosures
Commitments to lend additional funds to borrowers	$ 0
Loans modified in troubled debt restructuring | Delinquent
Troubled debt restructurings
Number of Loans | loan	0	1
Troubled debt restructurings		$ 126,000
One- to four-family residential
Troubled debt restructurings
Troubled debt restructurings	$ 824,000	$ 891,000
Additional disclosures
Percentage of mortgage loans representing total loan portfolio balance	97.10%
One- to four-family residential | Accrual Status
Troubled debt restructurings
Number of Loans | loan	2	3
Troubled debt restructurings	$ 414,000	$ 551,000
One- to four-family residential | Non Accrual Loans
Troubled debt restructurings
Number of Loans | loan	2	1
Troubled debt restructurings	$ 410,000	$ 340,000
Residential Mortgage
Additional disclosures
Mortgage loans in process of foreclosure, number of contracts | loan		0
Residential Mortgage | One- to four-family residential
Additional disclosures
Mortgage loans in process of foreclosure, number of contracts | loan	2
Mortgage loans in process of foreclosure, total value	$ 227,000

Loans Receivable and Allowan_10

Loans Receivable and Allowance for Loan Losses - Loan Payment Deferral Program by Class (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Additional disclosures
Loans in the Loan Payment Deferral Program	$ 63,168,000	$ 78,632,000
Percent of Total Loans	4.90%	6%
Delinquent amount	$ 145,000
Delinquent period	150 days
One- to four-family residential
Additional disclosures
Loans in the Loan Payment Deferral Program	$ 59,948,000	$ 74,704,000
Percent of Total Loans	4.60%	5.70%
Delinquent amount		$ 145,000
Delinquent period		150 days
Non-residential Mortgage
Additional disclosures
Loans in the Loan Payment Deferral Program	$ 3,220,000	$ 3,928,000
Percent of Total Loans	0.30%	0.30%

Loans Receivable and Allowan_11

Loans Receivable and Allowance for Loan Losses - Collateral, Sales, Serviced for Others, Directors and Executive Officers (Details)	12 Months Ended		24 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) loan	Dec. 31, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable
Residential mortgage loans sold, recognized gains		$ 663,000
Loans serviced for others	$ 36,000,000	41,300,000	$ 36,000,000
Loans serviced for others, securitization for which the company continues to hold the related mortgage-backed securities	20,700,000	24,300,000	$ 20,700,000
Loans serviced for others, amount of contractually specified servicing fees earned	101,000	127,000
Contractually Specified Servicing Fee Income, Statement of Income or Comprehensive Income [Extensible Enumeration]			Loan And Deposit Services, Fees And Commissions
Loans to related parties
Loans to directors and executive officers	$ 414,000	586,000	$ 414,000
Mortgage Loans on Real Estate | Maximum
Accounts, Notes, Loans and Financing Receivable
Loan to value ratio (as a percent)	80%		80%
Residential Mortgage Loans Held For Sale
Accounts, Notes, Loans and Financing Receivable
Residential mortgage loans sold, loan amount	$ 5,400,000	$ 36,200,000
Residential mortgage loans sold, recognized gains	$ 3,000
Number of nonaccrual loans | loan		0

Accrued Interest Receivable (De

Accrued Interest Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Components of accrued interest receivable
Accrued interest receivable	$ 6,115	$ 5,786
Loans receivable
Components of accrued interest receivable
Accrued interest receivable	4,595	4,644
Investment securities
Components of accrued interest receivable
Accrued interest receivable	1,497	1,126
Interest-bearing deposits
Components of accrued interest receivable
Accrued interest receivable	$ 23	$ 16

Interest Rate Lock and Forwar_3

Interest Rate Lock and Forward Loan Sale Commitments - Location of Assets and Liabilities (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Assets and liabilities related to derivatives
Fair value of asset derivatives	$ 9
Fair value of liability derivatives	9
Interest rate contracts | Prepaid expenses and other assets
Assets and liabilities related to derivatives
Fair value of asset derivatives	9
Interest rate contracts | Accounts payable and accrued expenses
Assets and liabilities related to derivatives
Fair value of liability derivatives	$ 9

Interest Rate Lock and Forwar_4

Interest Rate Lock and Forward Loan Sale Commitments - Location of Gains and Losses (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Interest Rate Lock and Forward Loan Sale Commitments
Gain (loss) related to derivatives	$ 0	$ 0

Premises and Equipment (Details

Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Premises and equipment
Gross	$ 26,830	$ 22,848
Less accumulated depreciation and amortization	(19,494)	(18,783)
Net	7,336	4,065
Construction in progress	263
Total	7,599	4,065
Depreciation expense	1,200	1,200
Land
Premises and equipment
Gross	585	585
Buildings and improvements
Premises and equipment
Gross	1,400	1,400
Leasehold improvements
Premises and equipment
Gross	17,949	14,683
Furniture, fixtures and equipment
Premises and equipment
Gross	6,766	6,062
Automobiles
Premises and equipment
Gross	$ 130	$ 118

Deposits (Details)

Deposits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Deposit amount
Non-interest bearing	$ 68,095,000	$ 69,980,000
Savings accounts	910,652,000	1,085,255,000
Certificates of deposit	429,687,000	225,054,000
Money market	5,372,000	5,368,000
Checking and Super NOW	302,346,000	296,171,000
Total	$ 1,716,152,000	$ 1,681,828,000
Interest rate
Savings accounts (as a percent)	0.13%	0.07%
Certificates of deposit (as a percent)	2.67%	0.85%
Money market (as a percent)	0.10%	0.10%
Checking and Super NOW (as a percent)	0.02%	0.02%
Total (as a percent)	0.74%	0.16%
Maturity of certificate of deposit accounts
2022	$ 356,940,000
2023	56,679,000
2024	6,264,000
2025	4,360,000
2026	5,444,000
Total	429,687,000	$ 225,054,000
Interest expense by type of deposit
Savings	949,000	1,074,000
Certificates of deposit and money market	3,914,000	2,845,000
Checking and Super NOW	62,000	56,000
Total	4,925,000	3,975,000
Overdrawn deposit accounts reclassified as loans	35,000	12,000
Directors and executive officer
Interest expense by type of deposit
Deposits	3,900,000	12,200,000
Domestic
Deposit with balances greater than or equal to $250,000
Total	$ 257,900,000	$ 109,600,000

Advances from the Federal Hom_3

Advances from the Federal Home Loan Bank (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2022
Federal Home Loan Bank advances
Federal Home Loan Bank stock, at cost	$ 8,173		$ 8,197
Federal Home Loan Bank, Advances, Rolling Maturity
Due within one year			24,000
Due over 1 year to 2 years	24,000		82,000
Due over 2 years to 3 years	82,000		25,000
Due over 3 years to 4 years	25,000		10,000
Due over 4 years to 5 years	10,000
Total	$ 141,000		$ 141,000
Weighted Average Rate
Due within one year (as a percent)			1.27%
Due over 1 year to 2 years (as a percent)	1.27%		1.40%
Due over 2 years to 3 years (as a percent)	1.40%		1.58%
Due over 3 years to 4 years (as a percent)	1.58%		1.97%
Due over 4 years to 5 years (as a percent)	1.97%
Total (as a percent)	1.45%		1.45%
Extended Maturity [Member]
Federal Home Loan Bank advances
FHLB advances restructured	$ 20,000
Federal Home Loan Bank stock, at cost	$ 20,000
Federal home loan bank, advances	1.45%	1.52%
Extended Term	4 months 24 days
FHLB Des Moines
Federal Home Loan Bank advances
Available additional unused FHLB advances	$ 800,900		$ 769,100
Territorial Savings Bank
Federal Home Loan Bank advances
Federal Home Loan Bank stock, at cost			$ 8,200
Territorial Savings Bank | FHLB Des Moines
Federal Home Loan Bank advances
Percentage of total assets used to determine maximum line of credit	45%		45%

Securities Sold Under Agreeme_3

Securities Sold Under Agreements to Repurchase - Summary of Repurchase Liability by Maturity (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Securities sold under agreements to repurchase
Repurchase Liability	$ 10,000,000	$ 10,000,000
Weighted Average
Securities sold under agreements to repurchase
Repurchase Liability	1.81	1.81
Over 1 year to 2 years
Securities sold under agreements to repurchase
Repurchase Liability	$ 5,000,000
Over 1 year to 2 years | Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)	1.81%
Over 2 years to 3 years
Securities sold under agreements to repurchase
Repurchase Liability	$ 5,000,000	$ 5,000,000
Over 2 years to 3 years | Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)	1.73%	1.88%
Over 3 years to 4 years
Securities sold under agreements to repurchase
Repurchase Liability		$ 5,000,000
Over 3 years to 4 years | Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)		1.73%

Securities Sold Under Agreeme_4

Securities Sold Under Agreements to Repurchase - Summary of Securities Pledged (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Securities sold under agreements to repurchase
Repurchase liability maximum	90%
Maturing Over 90 days
Securities sold under agreements to repurchase
Carrying Value of Securities	$ 13,562
Fair Value of Securities	11,351
Repurchase Liability	10,000
Amount at Risk	$ 3,562
Weighted Average Months to Maturity	24 months

Offsetting of Financial Liabi_3

Offsetting of Financial Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Securities sold under agreements to repurchase
Gross Amount of Recognized Liabilities	$ 10,000	$ 10,000
Net Amount of Liabilities Presented in the Balance Sheet	10,000	10,000
Gross amount not offset in the balance sheet
Financial Instruments	$ 10,000	$ 10,000

Income Taxes - Provision and Re

Income Taxes - Provision and Reconciliation to Federal Statutory Corporate Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Current
Federal	$ 2,911	$ 4,466
State	1,317	1,602
Total current	4,228	6,068
Deferred
Federal	990	205
State	100	100
Total deferred	1,090	305
Total income tax expense	$ 5,318	$ 6,373
Federal statutory corporate tax rate (as a percent)	21%	21%
Reconciliation of tax provision
Income tax expense at statutory rate	$ 4,510	$ 4,999
Income tax effect of:
State income taxes, net of federal income tax benefits	1,079	1,274
Other tax-exempt income	(166)	(164)
Share-based compensation	9	1
Meal and entertainment expenses	49	54
Non-deductible executive compensation	119	127
Recovery on bank-owned life insurance	(216)
Other	(66)	82
Total income tax expense	$ 5,318	$ 6,373
Effective income tax rate (as a percent)	24.76%	26.78%

Income Taxes - Components of In

Income Taxes - Components of Income Taxes Payable (Receivable) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Components of income taxes payable (receivable)
Current taxes payable		$ 1,863
Deferred taxes receivable	$ (1,643)	(1,927)
Income Tax Payable Receivable and Deferred Income Tax Assets, Net	838
State
Components of income taxes payable (receivable)
Current taxes payable	1,357	1,618
Deferred taxes receivable	(936)	(815)
Federal
Components of income taxes payable (receivable)
Current taxes (receivable)	(519)
Current taxes payable		245
Deferred taxes receivable	$ (707)	$ (1,112)

Income Taxes - Deferred Tax Com

Income Taxes - Deferred Tax Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Premises and equipment		$ 473
Hawaii franchise tax	$ 377	454
Allowance for loan losses	541	711
Employee benefit plans	2,714	2,703
Equity incentive plan	141	151
Unrealized losses on securities available-for-sale	725
Deferred compensation	199	240
Net lease liability	212	203
Other	16	44
Total	4,925	4,979
Deferred tax liabilities:
Deferred loan costs	2,601	2,654
Premises and equipment	254
FHLB stock dividends	125	126
Prepaid expense	226	186
Premium on loans sold	76	86
Total	3,282	3,052
Net deferred tax assets	$ 1,643	$ 1,927
Federal statutory corporate tax rate (as a percent)	21%	21%
Valuation allowance for deferred tax assets	$ 0	$ 0

Employee Benefit Plans - Pensio

Employee Benefit Plans - Pension Plan Participants (Details) - Pension Plan	12 Months Ended
	Dec. 31, 2022
Employee benefit plans
Vesting percentage for employees already enrolled with at least five years of service as of effective date of plan change	100%
Minimum service period for employees already enrolled to be 100% vested as of effective date of plan change	5 years
Vesting period if minimum service period for employees already enrolled was not met as of effective date of plan change	5 years
Minimum
Employee benefit plans
Required service period to participate in the plan	1 year

Employee Benefit Plans - Status

Employee Benefit Plans - Status of Pension Plan and SERP (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in projected benefit obligation:
Actuarial (gain) loss	$ 4,800	$ 2,900
Pension Plan
Employee benefit plans
Accumulated benefit obligation at end of year	15,865	20,943
Change in projected benefit obligation:
Benefit obligation at beginning of year	20,943	24,130
Service cost (income)	118	105
Interest cost	597	547
Actuarial (gain) loss	(4,802)	(2,885)
Benefits paid	(990)	(954)
Benefit obligation at end of year	15,866	20,943
Change in plan assets:
Fair value of plan assets at beginning of year	23,125	21,151
Actual return on plan assets	(3,799)	2,928
Benefits paid	(990)	(954)
Fair value of plan assets at end of year	18,336	23,125
Funded status at end of year	2,470	2,182
Amounts recognized in accumulated other comprehensive loss:
Net actuarial loss	7,708	7,401
Prior service cost	124	129
Accumulated other comprehensive loss, before tax	7,832	7,530	$ 7,530	$ 12,222
Pension Plan | Prepaid expenses and other assets
Amounts recognized in the Consolidated Balance Sheets:
Defined benefit plan Prepaid expenses and other assets	2,470	2,182
Supplemental Employee Retirement Plan (SERP)
Employee benefit plans
Accumulated benefit obligation at end of year	9,947	9,915
Change in projected benefit obligation:
Benefit obligation at beginning of year	9,915	9,866
Service cost (income)	(135)	(111)
Interest cost	179	177
Benefits paid	(11)	(17)
Benefit obligation at end of year	9,948	9,915
Change in plan assets:
Employer contributions	11	17
Benefits paid	(11)	(17)
Funded status at end of year	(9,948)	(9,915)
Supplemental Employee Retirement Plan (SERP) | Accounts payable and accrued expenses
Amounts recognized in the Consolidated Balance Sheets:
Accounts payable and accrued expenses - liability	$ (9,948)	$ (9,915)

Employee Benefit Plans - Change

Employee Benefit Plans - Changes Recognized in Accumulated Other Comprehensive Loss for Pension Plan (Details) - Pension Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Amounts recognized in accumulated other comprehensive loss:
Accumulated other comprehensive loss at beginning of year, before tax	$ 7,530	$ 7,530
Actuarial net (gain) loss arising during the period	517	(4,372)
Amortizations (recognized in net periodic benefit cost):
Actuarial loss	(210)	(315)
Prior service cost	(5)	(5)
Total recognized in other comprehensive loss	302	(4,692)
Accumulated other comprehensive loss at end of year, before tax	$ 7,832	$ 7,530

Employee Benefit Plans - Assump

Employee Benefit Plans - Assumptions Used to Determine Benefit Obligations and Pension Plan Investment Strategy (Details)	Dec. 31, 2022	Dec. 31, 2021
Pension Plan
Weighted average assumptions used to determine the year-end benefit obligations
Discount rate (as a percent)	5.40%	2.90%
Pension Plan | Domestic equity securities
Normal target allocation
Normal target allocation (as a percent)	55%
Pension Plan | International equity securities
Normal target allocation
Normal target allocation (as a percent)	10%
Pension Plan | Bonds
Normal target allocation
Normal target allocation (as a percent)	35%
Supplemental Employee Retirement Plan (SERP)
Weighted average assumptions used to determine the year-end benefit obligations
Discount rate (as a percent)	5%	5%
Rate of compensation increase (as a percent)	5%	5%

Employee Benefit Plans - Pens_2

Employee Benefit Plans - Pension Plan Assets Measured at Fair Value (Details) - Pension Plan - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assets measured at fair values
Fair value of assets	$ 18,336	$ 23,125	$ 21,151
Cash
Assets measured at fair values
Fair value of assets	1,452	1,017
Equities
Assets measured at fair values
Fair value of assets	11,659	16,276
Mutual funds
Assets measured at fair values
Fair value of assets	5,225	5,832
Level 1
Assets measured at fair values
Fair value of assets	18,336	23,125
Level 1 | Cash
Assets measured at fair values
Fair value of assets	1,452	1,017
Level 1 | Equities
Assets measured at fair values
Fair value of assets	11,659	16,276
Level 1 | Mutual funds
Assets measured at fair values
Fair value of assets	$ 5,225	$ 5,832

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended		24 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022
Net periodic benefit cost (income) for the year:
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]			Noninterest Income, Other Operating Income
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Noninterest Income, Other Operating Income
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration]			Noninterest Income, Other Operating Income
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Immediate Recognition of Actuarial Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Noninterest Income, Other Operating Income
Pension Plan
Estimated future benefit payments
2022	$ 998		$ 998
2023	1,016		1,016
2024	1,153		1,153
2025	1,216		1,216
2026	1,233		1,233
2027 - 2031	6,166		6,166
Total	$ 11,782		11,782
Assumptions used to determine the net periodic benefit cost:
Discount rate (as a percent)	2.90%	2.50%
Expected return on plan assets (as a percent)	6.75%	7%
Net periodic benefit cost (income) for the year:
Service cost (income)	$ 118	$ 105
Interest cost	597	547
Expected return on plan assets	(1,520)	(1,441)
Amortization of prior service cost	5	5
Recognized actuarial loss	210	315
Net periodic benefit cost	(590)	$ (469)
Supplemental Employee Retirement Plan (SERP)
Estimated future benefit payments
2023	8,733		8,733
2024	125		125
2025	125		125
2026	125		125
2027 - 2031	624		624
Total	$ 9,732		$ 9,732
Assumptions used to determine the net periodic benefit cost:
Discount rate (as a percent)	5%	5.03%
Rate of compensation increase (as a percent)	5%	5%
Net periodic benefit cost (income) for the year:
Service cost (income)	$ (135)	$ (111)
Interest cost	179	177
Net periodic benefit cost	$ 44	$ 66

Employee Benefit Plans - Define

Employee Benefit Plans - Defined Contribution and Profit Sharing Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Defined Contribution Plan Disclosure [Line Items]
Required service period to participate in plans	1 year
401(k) plan
Defined Contribution Plan Disclosure [Line Items]
Company matching contribution of employees' contributions (as a percent)	5%	5%
Employer's matching contribution (in dollars)	$ 64,000	$ 66,000
Profit sharing plan
Defined Contribution Plan Disclosure [Line Items]
Employer's matching contribution (in dollars)	$ 0	$ 0

Employee Stock Ownership Plan -

Employee Stock Ownership Plan - Loan, Expense and Shares (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 01, 2009	Dec. 31, 2022	Dec. 31, 2021
Employee Stock Ownership Plan
Allocated shares		583,474	540,869
Unearned shares		293,598	342,531
Total ESOP shares		877,072	883,400
Fair value of unearned shares, in thousands		$ 7,049	$ 8,649
ESOP
Employee Stock Ownership Plan
Amount borrowed from employer	$ 9,800
Shares purchased	978,650
Percentage of shares issued in initial public offering	8%
Employee stock ownership plan, price per share of shares acquired in initial public offering (in dollars per share)	$ 10
Term of loan		20 years
ESOP expense		$ 1,100	$ 1,300
ESOP | Prime rate
Employee Stock Ownership Plan
Variable interest rate		prime rate, as published in The Wall Street Journal

Employee Stock Ownership Plan_2

Employee Stock Ownership Plan - Nonqualified ESOP Restoration Plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
ESOP restoration | Certain executives
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits
Accrued (reversed) benefits	$ 144,000	$ 99,000

Share-Based Compensation - Plan

Share-Based Compensation - Plan Provisions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-Based Compensation
Compensation expense	$ 480	$ 351
Income tax benefit	$ 131	$ 96
2010 Equity Incentive Plan | Vesting period one
Share-Based Compensation
Vesting period	3 years
2010 Equity Incentive Plan | Vesting period two
Share-Based Compensation
Vesting period	5 years
2010 Equity Incentive Plan | Vesting period three
Share-Based Compensation
Vesting period	6 years
2019 Equity Incentive Plan
Share-Based Compensation
Shares remaining available for new awards under the 2019 Equity Plan	146,347

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Common Stock
Stock option activity
Exercised (in shares)	(272,211)	(210,244)
Stock Options
Stock option activity
Balance at beginning of period (in shares)	3,085	3,085
Expired (in shares)	3,085
Balance at end of period (in shares)		3,085	3,085
Weighted Average Exercise Price
Balance at beginning of period (in dollars per share)	$ 23.62	$ 23.62
Balance at end of period (in dollars per share)		$ 23.62	$ 23.62
Remaining Contractual Life
Options outstanding		8 months 1 day	1 year 8 months 1 day
Aggregate Intrinsic Value
Beginning of period	$ 5,000	$ 1,000
End of period		$ 5,000	$ 1,000
Unrecognized compensation costs	$ 0

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Awards (Details) - USD ($)		12 Months Ended
	Apr. 04, 2022	Dec. 31, 2022	Dec. 31, 2021
2019 Equity Incentive Plan
Unrecognized compensation
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		146,347
Restricted Stock
Restricted Stock Awards
Unvested at beginning of period (in shares)		23,208	23,695
Granted (in shares)		12,013	10,849
Vested (in shares)		11,557	11,336
Unvested at end of period (in shares)		23,664	23,208
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)		$ 24.61	$ 24.24
Granted (in dollars per share)		23.77	26.67
Vested (in dollars per share)		24.68	25.81
Unvested at end of period (in dollars per share)		$ 24.15	$ 24.61
Restricted Stock | 2019 Equity Incentive Plan
Restricted Stock Awards
Granted (in shares)		12,013
Unrecognized compensation
Vesting period		3 years
Unrecognized compensation costs		$ 251,000
Unrecognized compensation costs, period of recognition		1 year 7 months 6 days
Restricted Stock Units Based on a Performance Condition
Restricted Stock Awards
Unvested at beginning of period (in shares)		41,583	40,585
Granted (in shares)		14,412	13,016
Vested (in shares)		7,670	7,473
Forfeited (in shares)		4,768	4,545
Unvested at end of period (in shares)		43,557	41,583
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)		$ 24.68	$ 25.83
Granted (in dollars per share)		23.77	26.67
Vested (in dollars per share)		27.30	30.73
Forfeited (in dollars per share)		27.30	30.73
Unvested at end of period (in dollars per share)		$ 23.63	$ 24.68
Restricted Stock Units Based on a Performance Condition | 2019 Equity Incentive Plan
Restricted Stock Awards
Granted (in shares)		14,412
Unrecognized compensation
Vesting period		3 years
Unrecognized compensation costs		$ 57,000
Unrecognized compensation costs, period of recognition		1 year 9 months 18 days
Restricted Stock Units Based on a Performance Condition | Minimum | 2019 Equity Incentive Plan
Unrecognized compensation
Shares vesting as a percentage of target		0%
Restricted Stock Units Based on a Performance Condition | Maximum | 2019 Equity Incentive Plan
Unrecognized compensation
Shares vesting as a percentage of target		150%
Restricted Stock Units Based on a Market Condition
Restricted Stock Awards
Unvested at beginning of period (in shares)		10,396	10,147
Granted (in shares)		3,603	3,254
Vested (in shares)			1,628
Forfeited (in shares)		3,110	1,377
Unvested at end of period (in shares)		10,889	10,396
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)		$ 24.03	$ 24.69
Granted (in dollars per share)		24.42	25.94
Vested (in dollars per share)			28.32
Forfeited (in dollars per share)		24.45	28.32
Unvested at end of period (in dollars per share)		$ 24.04	24.03
Assumptions used in the Monte Carlo valuation of PRSUs
Term used for risk-free rate	2 years 8 months 26 days
Term used for risk-free rate and historical volatility	2 years 8 months 26 days
Risk-free interest rate (as a percent)	2.56%
Closing stock price (in dollars per share)	$ 23.77		$ 25.25
Annualized volatility (as a percent)	38.20%
Restricted Stock Units Based on a Market Condition | 2019 Equity Incentive Plan
Restricted Stock Awards
Granted (in shares)		3,603
Unrecognized compensation
Vesting period		3 years
Unrecognized compensation costs		$ 241,000
Unrecognized compensation costs, period of recognition		1 year 9 months 18 days

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share
Net income	$ 16,156	$ 17,430
Income allotted to participating securities	(98)	(75)
Net income available to common shareholders	$ 16,058	$ 17,355
Weighted-average number of shares used in:
Basic earnings per share (in shares)	8,865,946	9,059,204
Dilutive common stock equivalents:
Stock options and restricted stock units (in shares)	54,768	51,131
Diluted earnings per share (in shares)	8,920,714	9,110,335
Net income per common share, basic (in dollars per share)	$ 1.81	$ 1.92
Net income per common share, diluted (in dollars per share)	$ 1.80	$ 1.90

Other Comprehensive Loss - Chan

Other Comprehensive Loss - Changes in Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	$ (256,322)	$ (248,708)
Other comprehensive (income) loss, net of taxes	2,220	(3,167)
Net current period other comprehensive (income) loss	2,220	(3,167)
Balances at end of period	(256,550)	(256,322)
Accumulated Other Comprehensive (Loss)/Income
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	5,524	8,691
Other comprehensive (income) loss, net of taxes	2,220	(3,440)
Net current period other comprehensive (income) loss	2,220	(3,167)
Balances at end of period	7,744	5,524
Unfunded Pension Liability
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	5,524	8,967
Other comprehensive (income) loss, net of taxes	222	(3,443)
Net current period other comprehensive (income) loss	222	(3,443)
Balances at end of period	5,746	5,524
Unrealized (Gain) / Loss on Securities
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period		(276)
Other comprehensive (income) loss, net of taxes	1,998	3
Net current period other comprehensive (income) loss	1,998	276
Balances at end of period	$ 1,998
Amount Reclassified from Other Comprehensive Income
Changes in the components of accumulated other comprehensive loss, net of taxes
Other comprehensive (income) loss, net of taxes		273
Amounts reclassified from other comprehensive income, net of taxes		$ 273

Other Comprehensive Loss - Tax

Other Comprehensive Loss - Tax Effect on Each Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Tax effect on each component of other comprehensive loss
Pretax amount	$ 3,025	$ (4,315)
Tax	(805)	1,148
After Tax Amount	2,220	(3,167)
Unfunded Pension Liability
Tax effect on each component of other comprehensive loss
Pretax amount	302	(4,692)
Tax	(80)	1,249
After Tax Amount	222	(3,443)
Unrealized (Gain) / Loss on Securities
Tax effect on each component of other comprehensive loss
Pretax amount	2,723	4
Tax	(725)	(1)
After Tax Amount	$ 1,998	3
Amount Reclassified from Other Comprehensive Income
Tax effect on each component of other comprehensive loss
Pretax amount		373
Tax		(100)
After Tax Amount		$ 273

Regulatory Capital and Superv_3

Regulatory Capital and Supervision (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) item	Dec. 31, 2021 USD ($) item
Total Risk-Based Capital
Number of conditions or events that have changed the institution's category under capital guidelines | item	0	0
Territorial Savings Bank
Regulatory capital and supervision
Minimum capital conservation buffer	0.0250
Tier 1 Leverage Capital
Required Ratio	0.0500	0.0500
Actual Amount	$ 235,408	$ 235,785
Actual Ratio	0.1087	0.1109
Common Equity Tier 1 Risk-Based Capital
Required Ratio	9%	9%
Actual Amount	$ 235,408	$ 235,785
Actual Ratio	25.98%	26.47%
Tier 1 Risk-Based Capital
Required Ratio	0.1050	0.1050
Actual Amount	$ 235,408	$ 235,785
Actual Ratio	0.2598	0.2647
Total Risk-Based Capital
Required Ratio	0.1250	0.1250
Actual Amount	$ 237,488	$ 238,515
Actual Ratio	0.2620	0.2678
Territorial Bancorp Inc.
Regulatory capital and supervision
Threshold of assets requiring consolidated regulatory capital requirements identical to those applicable to subsidiary depository institutions	$ 3,000,000
Tier 1 Leverage Capital
Actual Amount	$ 264,295	$ 261,846
Actual Ratio	0.1221	0.1231
Common Equity Tier 1 Risk-Based Capital
Actual Amount	$ 264,295	$ 261,846
Actual Ratio	29.16%	29.40%
Tier 1 Risk-Based Capital
Actual Amount	$ 264,295	$ 261,846
Actual Ratio	0.2916	0.2940
Total Risk-Based Capital
Actual Amount	$ 266,375	$ 264,576
Actual Ratio	0.2939	0.2970

Commitments - Loans (Details)

Commitments - Loans (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Loan Commitments
Reserve balances	$ 0
Commitments to originate loans
Loan Commitments
Commitment amount	$ 1.2	$ 11.3
Commitments to originate loans | Minimum
Loan Commitments
Interest rate (as a percent)	5.25%	1.875%
Commitments to originate loans | Maximum
Loan Commitments
Interest rate (as a percent)	5.50%	2.875%
Unused lines of credit to borrowers
Loan Commitments
Commitment amount	$ 14.4	$ 15.4

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenues
Revenue from contracts with customers	$ 1,497	$ 2,507
Other revenue	1,923	683
Total	3,420	3,190
Service and Other Fees
Revenues
Revenue from contracts with customers	1,276	2,330
Other revenue	140	133
Other
Revenues
Revenue from contracts with customers	221	177
Other revenue	1,783	550
Total	$ 2,004	$ 727

Leases - Lease Costs (Details)

Leases - Lease Costs (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Leases
Minimum rental expense	$ 110,000	$ 110,000
Lease costs:
Operating lease costs	2,991,000	3,398,000
Short-term lease costs	296,000	47,000
Variable lease costs	165,000	156,000
Total lease costs	3,452,000	3,601,000
Cash paid for amounts included in measurement of lease liabilities	3,193,000	3,372,000
ROU assets obtained in exchange for new operating lease liabilities	$ 7,462,000	$ 4,060,000

Leases - Future Minimum Rental

Leases - Future Minimum Rental Commitments Under Non-cancellable Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Future minimum rental commitments:
2023	$ 2,894
2024	2,757
2025	2,137
2026	1,974
2026	1,896
Thereafter	10,995
Total	22,653
Less lease incentives to be received in 2023	(4,996)
Less present value discount	(2,362)
Present value of leases	$ 15,295	$ 10,744

Leases - Other Related Informat

Leases - Other Related Information (Details)	Dec. 31, 2022	Dec. 31, 2021
Leases
Weighted-average remaining lease term (years)	8 years 10 months 17 days	5 years 11 months 4 days
Weighted-average discount rate	2.03%	1.83%

Leases - Lease Payment Obligati

Leases - Lease Payment Obligations (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Leases
Total	$ 22,653

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Estimated Fair Values (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets
Investment securities available for sale, at fair value	$ 20,821
Investment securities held to maturity	591,084	$ 634,987
Carrying Amount
Assets
Cash and cash equivalents	40,553	99,859
Investment securities available for sale, at fair value	20,821
Investment securities held to maturity	717,773	636,442
Loans receivable, net	1,294,764	1,302,824
FHLB stock	8,197	8,173
FRB stock	3,170	3,158
Accrued interest receivable	6,115	5,786
Interest rate contracts		9
Liabilities
Deposits	1,716,152	1,681,828
Advances from the Federal Home Loan Bank	141,000	141,000
Securities sold under agreements to repurchase	10,000	10,000
Accrued interest payable	701	35
Interest rate contracts		9
Estimated Fair Value
Assets
Cash and cash equivalents	40,553	99,859
Investment securities available for sale, at fair value	20,821
Investment securities held to maturity	591,084	634,987
Loans receivable, net	1,180,840	1,314,609
FHLB stock	8,197	8,173
FRB stock	3,170	3,158
Accrued interest receivable	6,115	5,786
Interest rate contracts		9
Liabilities
Deposits	1,708,612	1,682,078
Advances from the Federal Home Loan Bank	133,145	141,867
Securities sold under agreements to repurchase	9,440	10,143
Accrued interest payable	701	35
Interest rate contracts		9
Estimated Fair Value | Level 1
Assets
Cash and cash equivalents	40,553	99,859
Accrued interest receivable	23	16
Estimated Fair Value | Level 2
Assets
Investment securities available for sale, at fair value	20,821
Investment securities held to maturity	591,084	634,987
FHLB stock	8,197	8,173
FRB stock	3,170	3,158
Accrued interest receivable	1,497	1,126
Interest rate contracts		9
Liabilities
Deposits	1,286,465	1,456,773
Advances from the Federal Home Loan Bank	133,145	141,867
Securities sold under agreements to repurchase	9,440	10,143
Accrued interest payable	33	34
Interest rate contracts		9
Estimated Fair Value | Level 3
Assets
Loans receivable, net	1,180,840	1,314,609
Accrued interest receivable	4,595	4,644
Liabilities
Deposits	422,147	225,305
Accrued interest payable	$ 668	$ 1

Fair Value of Financial Instr_4

Fair Value of Financial Instruments - Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets and Liabilities Measured at Fair Value on Recurring Basis
Investment securities available for sale, at fair value	$ 20,821
Fair Value, Measurements, Recurring
Assets and Liabilities Measured at Fair Value on Recurring Basis
Interest rate contracts - assets		$ 9
Interest rate contracts - liabilities		(9)
Investment securities available for sale, at fair value	20,821
Fair Value, Measurements, Recurring | Level 2
Assets and Liabilities Measured at Fair Value on Recurring Basis
Interest rate contracts - assets		9
Interest rate contracts - liabilities		$ (9)
Investment securities available for sale, at fair value	$ 20,821

Parent Company Only - Condensed

Parent Company Only - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assets
Prepaid expenses and other assets	$ 6,676	$ 6,963
Total assets	2,169,592	2,130,602
Liabilities and Equity
Equity	256,550	256,322	$ 248,708
Total liabilities and stockholders' equity	2,169,592	2,130,602
Territorial Bancorp Inc.
Assets
Cash	28,515	25,532
Investment in Territorial Savings Bank	227,663	230,261
Receivable from Territorial Savings Bank	408	566
Prepaid expenses and other assets	105	132
Total assets	256,691	256,491
Liabilities and Equity
Other liabilities	141	170
Equity	256,550	256,321
Total liabilities and stockholders' equity	$ 256,691	$ 256,491

Parent Company Only - Condens_2

Parent Company Only - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Interest and dividend income:
Total interest income	$ 62,702	$ 60,301
Noninterest expense:
Salaries	22,259	22,091
Other general and administrative expenses	4,252	4,661
Total noninterest expense	38,798	38,286
Income before income taxes	21,474	23,803
Income taxes	5,318	6,373
Net income	16,156	17,430
Territorial Bancorp Inc.
Interest and dividend income:
Dividends from Territorial Savings Bank	17,500	22,000
Interest-earning deposit with Territorial Savings Bank	4	5
Total interest income	17,504	22,005
Noninterest expense:
Salaries	42	43
Other general and administrative expenses	656	998
Total noninterest expense	698	1,041
Income before income taxes	16,806	20,964
Income taxes	(209)	(288)
Income before equity in undistributed earnings in subsidiaries	17,015	21,252
Equity in undistributed earnings of Territorial Savings Bank, net of dividends	(859)	(3,822)
Net income	$ 16,156	$ 17,430

Parent Company Only - Condens_3

Parent Company Only - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 16,156	$ 17,430
Adjustments to reconcile net income to net cash provided by operating activities:
Net decrease in prepaid expenses and other assets	289	(4,119)
Net cash from operating activities	16,666	12,524
Cash flows from investing activities:
Net cash from investing activities	(95,252)	(283,012)
Cash flows from financing activities:
Repurchases of common stock	(5,973)	(5,000)
Cash dividends paid	(9,071)	(10,224)
Net cash from financing activities	19,280	6,804
Net decrease in cash and cash equivalents	(59,306)	(263,684)
Cash and cash equivalents at beginning of the year	99,859	363,543
Cash and cash equivalents at end of the year	40,553	99,859
Territorial Bancorp Inc.
Cash flows from operating activities:
Net income	16,156	17,430
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of Territorial Savings Bank, net of dividends	859	3,822
Net decrease in prepaid expenses and other assets	1,275	1,762
Net decrease in other liabilities	(263)	(366)
Net cash from operating activities	18,027	22,648
Cash flows from financing activities:
Repurchases of common stock	(5,973)	(5,000)
Cash dividends paid	(9,071)	(10,224)
Net cash from financing activities	(15,044)	(15,224)
Net decrease in cash and cash equivalents	2,983	7,424
Cash and cash equivalents at beginning of the year	25,532	18,108
Cash and cash equivalents at end of the year	$ 28,515	$ 25,532

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares		12 Months Ended
	Jan. 26, 2023	Dec. 31, 2022	Dec. 31, 2021
Subsequent Events
Quarterly cash dividend declared on common stock (in dollars per share)		$ 1.02	$ 1.02
Subsequent event
Subsequent Events
Quarterly cash dividend declared on common stock (in dollars per share)	$ 0.23

Investment Securities - Amort_2

Investment Securities - Amortized Cost and Fair Values of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Investment Securities.
Amortized Cost	$ 717,773	$ 636,442
Estimated Fair Value	$ 591,084	$ 634,987