Territorial Bancorp (TBNK) 10-Q 10 May 24 2024 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	Apr. 30, 2024
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2024
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 Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		8,832,235
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001447051
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
ASSETS
Cash and cash equivalents	$ 90,059	$ 126,659
Investment securities available for sale, at fair value	19,483	20,171
Investment securities held to maturity, at amortized cost (fair value of $547,290 and $568,128 at March 31, 2024 and December 31, 2023, respectively)	677,578	685,728
Loans receivable	1,309,712	1,308,552
Allowance for credit losses	(5,142)	(5,121)
Loans receivable, net of allowance for credit losses	1,304,570	1,303,431
Federal Home Loan Bank stock, at cost	12,232	12,192
Federal Reserve Bank stock, at cost	3,182	3,180
Accrued interest receivable	6,281	6,105
Premises and equipment, net	7,144	7,185
Right-of-use asset, net	12,080	12,371
Bank-owned life insurance	48,884	48,638
Income taxes receivable	604	344
Deferred income tax assets, net	2,820	2,457
Prepaid expenses and other assets	8,112	8,211
Total assets	2,193,029	2,236,672
Liabilities:
Deposits	1,600,148	1,636,604
Advances from the Federal Home Loan Bank	242,000	242,000
Advances from the Federal Reserve Bank	50,000	50,000
Securities sold under agreements to repurchase	10,000	10,000
Accounts payable and accrued expenses	20,113	23,334
Lease liability	17,597	17,297
Advance payments by borrowers for taxes and insurance	3,155	6,351
Total liabilities	1,943,013	1,985,586
Stockholders' Equity:
Common stock, $0.01 par value; authorized 100,000,000 shares; issued and outstanding 8,826,613 shares at March 31, 2024 and December 31, 2023, respectively	88	88
Additional paid-in capital	48,098	48,022
Unearned ESOP shares	(2,324)	(2,447)
Retained earnings	210,771	211,644
Accumulated other comprehensive loss	(6,617)	(6,221)
Total stockholders' equity	250,016	251,086
Total liabilities and stockholders' equity	$ 2,193,029	$ 2,236,672

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Consolidated Balance Sheets
Investment securities held to maturity, fair value (in dollars)	$ 547,290	$ 568,128
Common stock, par value (in dollars per share)	$ 0.01
Common stock, authorized shares	50,000,000
Common stock, shares issued	8,826,613
Common stock, shares outstanding		9,071,076

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest income:
Loans	$ 12,065	$ 11,454
Investment securities	4,313	4,540
Other investments	1,613	727
Total interest income	17,991	16,721
Interest expense:
Deposits	6,779	3,530
Advances from the Federal Home Loan Bank	1,810	1,054
Advances from the Federal Reserve Bank	595
Securities sold under agreements to repurchase	46	46
Total interest expense	9,230	4,630
Net interest income	8,761	12,091
Provision (reversal of provision) for credit losses	19	(100)
Net interest income after provision (reversal of provision) for credit losses	8,742	12,191
Noninterest income:
Service and other fees	273	310
Income on bank-owned life insurance	246	203
Net gain on sale of loans		1
Other	74	75
Total noninterest income	593	589
Noninterest expense:
Salaries and employee benefits	4,962	5,404
Occupancy	1,738	1,623
Equipment	1,323	1,312
Federal deposit insurance premiums	496	245
Other general and administrative expenses	1,541	1,029
Total noninterest expense	10,060	9,613
(Loss) income before income taxes	(725)	3,167
Income tax (benefit) expense	(243)	851
Net (loss) income	$ (482)	$ 2,316
Basic (loss) earnings per share (in dollars per share)	$ (0.06)	$ 0.26
Diluted (loss) earnings per share (in dollars per share)	(0.06)	0.26
Cash dividends declared per common share (in dollars per share)	$ 0.05	$ 0.23
Basic weighted-average shares outstanding (in shares)	8,588,137	8,774,634
Diluted weighted-average shares outstanding (in shares)	8,630,719	8,806,744

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Consolidated Statements of Comprehensive Income
Net (loss) income	$ (482)	$ 2,316
Unrealized (loss) gain on securities	(396)	337
Total other comprehensive (loss) income, net of tax	(396)	337
Comprehensive (loss) income	$ (878)	$ 2,653

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, 2022	$ 91	$ 51,825	$ (2,936)	$ 215,314	$ (7,744)	$ 256,550
Balance (in shares) at Dec. 31, 2022	9,071,076
Increase (Decrease) in Stockholders' Equity
Net (loss) income				2,316		2,316
Other comprehensive (loss) income					337	337
Cumulative change in accounting principle (1)				(2,319)		(2,319)
Cash dividends declared				(1,975)		(1,975)
Share-based compensation		(42)				(42)
Share-based compensation (in shares)	4,540
Allocation of ESOP shares		159	122			281
Repurchase of shares of common stock	$ (1)	(1,386)				(1,387)
Repurchase of shares of common stock (in shares)	(69,065)
Balance at Mar. 31, 2023	$ 90	50,556	(2,814)	213,336	(7,407)	253,761
Balance (in shares) at Mar. 31, 2023	9,006,551
Balance at Dec. 31, 2023	$ 88	48,022	(2,447)	211,644	(6,221)	251,086
Balance (in shares) at Dec. 31, 2023	8,826,613
Increase (Decrease) in Stockholders' Equity
Net (loss) income				(482)		(482)
Other comprehensive (loss) income					(396)	(396)
Cash dividends declared				(391)		(391)
Share-based compensation		81				81
Allocation of ESOP shares		(5)	123			118
Balance at Mar. 31, 2024	$ 88	$ 48,098	$ (2,324)	$ 210,771	$ (6,617)	$ 250,016
Balance (in shares) at Mar. 31, 2024	8,826,613

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Consolidated Statements of Stockholders' Equity, Share Data
Cash dividends declared per common share (in dollars per share)	$ 0.05	$ 0.23
Allocation of ESOP shares, shares	12,234
Common Stock
Consolidated Statements of Stockholders' Equity, Share Data
Allocation of ESOP shares, shares		12,234

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net (loss) income	$ (482)	$ 2,316
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Provision (reversal of provision) for credit losses	19
Reversal of provision for credit losses		(100)
Depreciation and amortization	242	292
Deferred income tax (benefit) expense	(220)	266
Accretion of fees, discounts, and premiums, net	(60)	(90)
Amortization of right-of-use asset	695	716
Origination of loans held for sale		(355)
Proceeds from sales of loans held for sale		356
Gain on sale of loans, net		(1)
ESOP expense	118	281
Share-based compensation expense	81	(42)
Net increase in accrued interest receivable	(169)	(13)
Income on bank-owned life insurance	(246)	(203)
Net decrease (increase) in prepaid expenses and other assets	99	(154)
Net decrease in accounts payable and accrued expenses	(3,183)	(1,661)
Net decrease in lease liability	(104)	(694)
Net decrease in advance payments by borrowers for taxes and insurance	(3,196)	(2,691)
Net (decrease) increase in income taxes payable	(260)	196
Net cash used in operating activities	(6,666)	(1,581)
Cash flows from investing activities:
Purchases of investment securities held to maturity		(6,693)
Principal repayments on investment securities held to maturity	8,162	8,879
Principal repayments on investment securities available for sale	159	220
Principal repayments on loans receivable, net of loan originations	(1,126)	409
Purchases of Federal Home Loan Bank stock	(40)	(5,087)
Proceeds from redemption of Federal Home Loan Bank stock		840
Purchases of Federal Reserve Bank stock	(3)	(7)
Purchases of premises and equipment	(202)	(116)
Net cash from (used in) investing activities	6,950	(1,555)
Cash flows from financing activities:
Net decrease in deposits	(36,456)	(54,179)
Proceeds from advances from the Federal Home Loan Bank		126,000
Repayments of advances from the Federal Home Loan Bank		(21,000)
Purchases of Fed Funds	100,000
Sales of Fed Funds	(100,000)
Repurchases of common stock		(1,345)
Cash dividends paid	(428)	(2,033)
Net cash (used in) financing activities	(36,884)	47,443
Net change in cash and cash equivalents	(36,600)	44,307
Cash and cash equivalents at beginning of the year	126,659	40,553
Cash and cash equivalents at end of the year	90,059	84,860
Cash paid for:
Interest on deposits and borrowings	9,128	4,318
Income taxes	237	390
Supplemental disclosure of noncash investing and financing activities:
Company stock repurchased through stock swap and net settlement transactions		43
Establishment of right-of-use asset, net of incentives and modifications	404	118
Establishment of lease liability, net of modifications	$ 404	$ 118

Organization

Organization	3 Months Ended
	Mar. 31, 2024
Organization
Organization	(1) Organization ​ Territorial Bancorp Inc. (the Company) is a Maryland corporation and is the holding company for Territorial Savings Bank (the 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 one subsidiary, Territorial Financial Services, Inc.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	(2) Summary of Significant Accounting Policies ​ (a) Basis of Presentation ​ The accompanying unaudited interim condensed consolidated financial statements of Territorial Bancorp Inc. have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited interim condensed consolidated financial statements and notes should be read in conjunction with the Company’s consolidated financial statements and notes thereto filed as part of the Annual Report on Form 10-K for the year ended December 31, 2023. In the opinion of management, all adjustments necessary for a fair presentation have been made and consist only of normal recurring adjustments. Interim results of operations are not necessarily indicative of results to be expected for the year. ​ (b) Allowance of Credit Losses (ACL) on Loans and Securities ​	(2) Summary of Significant Accounting Policies ​ (a) Basis of Presentation ​ The accompanying unaudited interim condensed consolidated financial statements of Territorial Bancorp Inc. have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited interim condensed consolidated financial statements and notes should be read in conjunction with the Company’s consolidated financial statements and notes thereto filed as part of the Annual Report on Form 10-K for the year ended December 31, 2023. In the opinion of management, all adjustments necessary for a fair presentation have been made and consist only of normal recurring adjustments. Interim results of operations are not necessarily indicative of results to be expected for the year. ​ (b) Allowance of Credit Losses (ACL) on Loans and Securities ​

Recently Issued and Adopted Acc

Recently Issued and Adopted Accounting Pronouncements	3 Months Ended
	Mar. 31, 2024
Recently Issued Accounting Pronouncements
Recently Issued Accounting Pronouncements	(3) Recently Issued and Adopted Accounting Pronouncements ​ In June 2022, the Financial Accounting Standards Board (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 Federal Home Loan Bank (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 publicly traded and can only be issued, exchanged, redeemed or repurchased by the FRB and the FHLB. ASU 2022-03 was effective for fiscal years beginning after December 15, 2023. The Company adopted the standard on January 1, 2024, and it did not have a material effect on its consolidated financial statements. ​ In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the U.S. Securities and Exchange Commission’s (SEC) Disclosure Update and Simplification Initiative. The ASU is intended to clarify or improve disclosure and presentation requirements of a variety of topics. Many of the amendment will allow users to more easily compare entities subject to the SEC’s existing disclosures with those entities that were not previously subject to the requirements and align the requirements in the FASB accounting standard codification with the SEC’s regulations. The Company is currently evaluating the effects that ASU 2023-06 will have on its consolidated financial statements. ​ In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This ASU is intended to improve financial reporting by requiring disclosure of incremental segment information on an annual and interim basis to enable investors to develop more decision-useful financial analyses. This ASU will be effective for fiscal years beginning after December 31, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company does not expect the adoption of this ASU to have a material effect on its consolidated financial statements. ​ In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The ASU is intended to enhance the transparency and decision usefulness of income tax disclosures. This ASU will be effective for fiscal years beginning after December 15, 2024. The Company is currently evaluating the effects that ASU 2023-09 will have on its consolidated financial statements.

Cash and Cash Equivalents

Cash and Cash Equivalents	3 Months Ended
	Mar. 31, 2024
Cash and Cash Equivalents
Cash and Cash Equivalents	(4) Cash and Cash Equivalents ​ The table below presents the balances of cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, (Dollars in thousands) 2024 2023 Cash and due from banks ​ $ 10,714 ​ $ 10,471 ​ ​ Interest-earning deposits in other banks ​ 79,345 ​ 116,188 ​ ​ Cash and cash equivalents ​ $ 90,059 ​ $ 126,659 ​ ​ ​ Interest-earning deposits in other banks consist primarily of deposits at the Federal Reserve Bank of San Francisco.

Investment Securities

Investment Securities	3 Months Ended
	Mar. 31, 2024
Investment Securities
Investment Securities	(5) Investment Securities ​ The amortized cost, gross unrealized gains and losses, fair value, and related ACL of investment securities are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross Unrealized ​ Estimated ​ ​ (Dollars in thousands) Cost Gains Losses Fair Value ACL March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ 22,415 ​ $ — $ (2,932) ​ $ 19,483 ​ $ — Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ 677,578 ​ ​ 36 ​ (130,324) ​ ​ 547,290 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 699,993 ​ $ 36 $ (133,256) ​ $ 566,773 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ 22,563 ​ $ — $ (2,392) ​ $ 20,171 ​ $ — Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ 685,728 ​ ​ 68 ​ (117,668) ​ ​ 568,128 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 708,291 ​ $ 68 $ (120,060) ​ $ 588,299 ​ $ — ​ The amortized cost and estimated fair value of investment securities by maturity date at March 31, 2024 are shown below. Incorporated in the maturity schedule are mortgage-backed securities, which are allocated using the contractual maturity as a basis. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized Estimated (Dollars in thousands) Cost Fair Value Available-for-sale: ​ ​ ​ ​ ​ ​ ​ Due after 10 years ​ $ 22,415 ​ $ 19,483 ​ Total ​ $ 22,415 ​ $ 19,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ Due within 5 years ​ $ 12 ​ $ 12 ​ Due after 5 years through 10 years ​ 6 ​ 6 ​ Due after 10 years ​ 677,560 ​ 547,272 ​ Total ​ $ 677,578 ​ $ 547,290 ​ ​ The Company did not sell any held-to-maturity or available-for-sale securities during the three months ended March 31, 2024 and 2023. ​ Investment securities with amortized costs of $549.7 million and $555.8 million at March 31, 2024 and December 31, 2023, respectively, were pledged to secure deposits made by state and local governments, securities sold under agreements to repurchase, transaction clearing accounts, and Federal Reserve Bank borrowings. Included in these amounts were $220.9 million and $74.0 million pledged to the Federal Reserve Bank’s discount window at March 31, 2024 and December 31, 2023, respectively, and $52.6 million and $202.1 million pledged to the Federal Reserve Bank’s Bank Term Funding Program at March 31, 2024 and December 31, 2023, respectively. ​ Provided below is a summary of investment securities which were in an unrealized loss position at March 31, 2024 and December 31, 2023. 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) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ — ​ $ — ​ $ 19,483 ​ $ (2,932) 4 ​ $ 19,483 ​ $ (2,932) ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ — ​ ​ — ​ ​ 544,088 ​ ​ (130,324) 152 ​ ​ 544,088 ​ ​ (130,324) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ — ​ $ — ​ $ 563,571 ​ $ (133,256) ​ 156 ​ $ 563,571 ​ $ (133,256) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government sponsored enterprises ​ $ — ​ $ — ​ $ 20,171 ​ $ (2,392) 4 ​ $ 20,171 ​ $ (2,392) ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ 10,326 ​ ​ (107) ​ ​ 554,514 ​ ​ (117,561) 152 ​ ​ 564,840 ​ ​ (117,668) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 10,326 ​ $ (107) ​ $ 574,685 ​ $ (119,953) ​ 156 ​ $ 585,011 ​ $ (120,060) ​ ​ 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, 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, no allowance for credit losses was recorded for these securities as of March 31, 2024 or December 31, 2023.

Loans Receivable and Allowance

Loans Receivable and Allowance for Loan Losses	3 Months Ended
	Mar. 31, 2024
Loans Receivable and Allowance for Credit Losses
Loans Receivable and Allowance for Credit Losses	(6) Loans Receivable and Allowance for Credit Losses ​ The components of loans receivable, net of allowance for credit losses (ACL) as of March 31, 2024 and December 31, 2023 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, (Dollars in thousands) 2024 2023 Real estate loans: ​ ​ ​ ​ ​ ​ First mortgages: ​ ​ ​ ​ ​ ​ One- to four-family residential ​ $ 1,275,897 ​ $ 1,277,544 Multi-family residential ​ 5,604 ​ 5,855 Construction, commercial, and other ​ 12,554 ​ 11,631 Home equity loans and lines of credit ​ 9,219 ​ 7,058 Total real estate loans ​ 1,303,274 ​ 1,302,088 Other loans: ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ 180 ​ 196 Consumer and other loans ​ 8,305 ​ 8,257 Total other loans ​ ​ 8,485 ​ ​ 8,453 ​ ​ ​ ​ ​ ​ ​ Total loans ​ 1,311,759 ​ 1,310,541 ​ ​ ​ ​ ​ ​ ​ Net unearned fees and discounts ​ (2,047) ​ (1,989) Total loans, net of unearned fees and discounts ​ 1,309,712 ​ 1,308,552 ​ ​ ​ ​ ​ ​ ​ Allowance for credit losses ​ (5,142) ​ (5,121) Loans receivable, net of allowance for credit losses ​ $ 1,304,570 ​ $ 1,303,431 ​ The table below presents the activity in the allowance for credit losses by portfolio segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Commercial Consumer ​ (Dollars in thousands) Estate Loans Loans ​ Unallocated Totals Three months ended March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 4,502 ​ $ 514 ​ $ 105 ​ $ — ​ $ 5,121 (Reversal of provision) provision for credit losses ​ (26) ​ ​ 12 ​ ​ 33 ​ ​ — ​ 19 ​ ​ 4,476 ​ 526 ​ 138 ​ — ​ 5,140 Charge-offs ​ (2) ​ ​ — ​ ​ (6) ​ ​ — ​ (8) Recoveries ​ 9 ​ ​ — ​ ​ 1 ​ ​ — ​ 10 Net recoveries (charge-offs) ​ 7 ​ — ​ (5) ​ — ​ 2 Balance, end of period ​ $ 4,483 ​ $ 526 ​ $ 133 ​ $ — ​ $ 5,142 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,263 ​ $ 434 ​ $ 76 ​ $ 259 ​ $ 2,032 Adoption of ASU No. 2016-13 ​ ​ 3,393 ​ ​ 71 ​ ​ 4 ​ ​ (259) ​ ​ 3,209 (Reversal of provision) provision for credit losses ​ (27) ​ ​ (88) ​ ​ 15 ​ ​ — ​ (100) ​ ​ 4,629 ​ 417 ​ 95 ​ — ​ 5,141 Charge-offs ​ — ​ — ​ (15) ​ — ​ (15) Recoveries ​ — ​ — ​ 1 ​ — ​ 1 Net charge-offs ​ — ​ — ​ (14) ​ — ​ (14) Balance, end of period ​ $ 4,629 ​ $ 417 ​ $ 81 ​ $ — ​ $ 5,127 ​ The credit loss provisions in the three months ended March 31, 2024 was primarily due to an increase in our consumer and commercial loan portfolios, an increase in forecasted charge-offs in the consumer loan portfolio, and a decrease in forecasted prepayments in the commercial loan portfolio. The reversal of credit loss provisions in the three months ended March 31, 2023 was primarily due to an improvement in economic conditions. The Company primarily uses the aging of loans to monitor the credit quality of its loan portfolio. The table below presents by credit quality indicator, loan class, and year of origination, the amortized cost basis of the Company’s loans as of March 31, 2024. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revolving Loans ​ ​ ​ ​ Amortized Cost of Term Loans by Origination Year ​ Amortized ​ ​ ​ (Dollars in thousands) ​ 2024 ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ Prior ​ Cost Basis ​ Total March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Loans not past due ​ ​ 55 ​ ​ 613 ​ ​ 336 ​ ​ 4,797 ​ ​ — ​ ​ 1,013 ​ ​ 1,236 ​ ​ 8,050 Total Commercial ​ ​ 55 ​ ​ 613 ​ ​ 336 ​ ​ 4,797 ​ ​ — ​ ​ 1,013 ​ ​ 1,236 ​ ​ 8,050 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ 9 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 9 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 170 ​ ​ 170 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 1 ​ ​ 1 Loans not past due ​ ​ 97 ​ ​ 46 ​ ​ 73 ​ ​ 13 ​ ​ 3 ​ ​ 52 ​ ​ 8,194 ​ ​ 8,478 Total Consumer ​ ​ 106 ​ ​ 46 ​ ​ 73 ​ ​ 13 ​ ​ 3 ​ ​ 52 ​ ​ 8,365 ​ ​ 8,658 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Estate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 98 ​ ​ — ​ ​ 98 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 87 ​ ​ — ​ ​ 87 Loans not past due ​ ​ 15,987 ​ ​ 90,595 ​ ​ 128,031 ​ ​ 281,382 ​ ​ 182,584 ​ ​ 594,240 ​ ​ — ​ ​ 1,292,819 Total Real Estate ​ ​ 15,987 ​ ​ 90,595 ​ ​ 128,031 ​ ​ 281,382 ​ ​ 182,584 ​ ​ 594,425 ​ ​ — ​ ​ 1,293,004 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 16,148 ​ $ 91,254 ​ $ 128,440 ​ $ 286,192 ​ $ 182,587 ​ $ 595,490 ​ $ 9,601 ​ $ 1,309,712 ​ The Company did not have any revolving loans that converted to term loans during the three months ended March 31, 2024. ​ The table below presents by credit quality indicator, loan class, and year of origination, the amortized cost basis of the Company’s loans as of December 31, 2023. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revolving Loans ​ ​ ​ ​ Amortized Cost of Term Loans by Origination Year ​ Amortized ​ ​ ​ (Dollars in thousands) ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ 2019 ​ Prior ​ Cost Basis ​ Total December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Loans not past due ​ ​ 387 ​ ​ 353 ​ ​ 4,836 ​ ​ — ​ ​ 203 ​ ​ 856 ​ ​ 1,230 ​ ​ 7,865 Total Commercial ​ ​ 387 ​ ​ 353 ​ ​ 4,836 ​ ​ — ​ ​ 203 ​ ​ 856 ​ ​ 1,230 ​ ​ 7,865 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ 4 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 4 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Loans not past due ​ ​ 271 ​ ​ 80 ​ ​ 20 ​ ​ 4 ​ ​ 14 ​ ​ 42 ​ ​ 6,137 ​ ​ 6,568 Total Consumer ​ ​ 275 ​ ​ 80 ​ ​ 20 ​ ​ 4 ​ ​ 14 ​ ​ 42 ​ ​ 6,137 ​ ​ 6,572 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Estate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 428 ​ ​ — ​ ​ 428 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 140 ​ ​ 87 ​ ​ — ​ ​ 227 Loans not past due ​ ​ 91,195 ​ ​ 129,148 ​ ​ 283,571 ​ ​ 183,887 ​ ​ 91,113 ​ ​ 514,546 ​ ​ — ​ ​ 1,293,460 Total Real Estate ​ ​ 91,195 ​ ​ 129,148 ​ ​ 283,571 ​ ​ 183,887 ​ ​ 91,253 ​ ​ 515,061 ​ ​ — ​ ​ 1,294,115 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 91,857 ​ $ 129,581 ​ $ 288,427 ​ $ 183,891 ​ $ 91,470 ​ $ 515,959 ​ $ 7,367 ​ $ 1,308,552 ​ The Company did not have any revolving loans that converted to term loans during the year ended December 31, 2023. ​ The following table presents by loan class and year of origination, the gross charge-offs recorded during the three months ended March 31, 2024 and 2023. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2024 ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ Prior ​ Total Three months ended March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ 2 ​ $ 2 Loans on deposit accounts ​ ​ — ​ ​ 3 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 3 Consumer and other ​ ​ — ​ ​ 3 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 3 Total ​ $ — ​ $ 6 ​ $ — ​ $ — ​ $ — ​ $ 2 ​ $ 8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ 2019 ​ Prior ​ Total Three months ended March 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ $ 15 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — Total ​ $ 15 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ 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 March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 98 ​ $ — ​ $ 87 ​ $ 185 ​ $ 1,273,726 ​ $ 1,273,911 ​ $ 2,026 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 5,597 ​ 5,597 ​ — ​ — ​ Construction, commercial, and other mortgages ​ — ​ — ​ — ​ — ​ 12,493 ​ 12,493 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 9,221 ​ 9,221 ​ 9 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 180 ​ 180 ​ — ​ — ​ Consumer and other ​ 9 ​ 170 ​ 1 ​ 180 ​ 8,130 ​ 8,310 ​ 170 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 107 ​ $ 170 ​ $ 88 ​ $ 365 ​ $ 1,309,347 ​ $ 1,309,712 ​ $ 2,205 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 428 ​ $ — ​ $ 227 ​ $ 655 ​ $ 1,274,960 ​ $ 1,275,615 ​ $ 2,079 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 5,848 ​ 5,848 ​ — ​ — ​ Construction, commercial, and other mortgages ​ — ​ — ​ — ​ — ​ 11,570 ​ 11,570 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 7,060 ​ 7,060 ​ 11 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 196 ​ 196 ​ — ​ — ​ Consumer and other ​ 4 ​ — ​ — ​ 4 ​ 8,259 ​ 8,263 ​ 170 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 432 ​ $ — ​ $ 227 ​ $ 659 ​ $ 1,307,893 ​ $ 1,308,552 ​ $ 2,260 ​ $ — ​ ​ ​ The table below presents the amortized cost basis of loans on nonaccrual status as of March 31, 2024 and December 31, 2023. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Nonaccrual Loans With a Related ACL Nonaccrual Loans Without a Related ACL Total Nonaccrual Loans March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,535 ​ $ 491 ​ $ 2,026 Home equity loans and lines of credit ​ ​ 9 ​ ​ — ​ ​ 9 Consumer and other ​ ​ 170 ​ ​ — ​ ​ 170 Total Nonaccrual Loans and Leases ​ $ 1,714 ​ $ 491 ​ $ 2,205 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,030 ​ $ 1,049 ​ $ 2,079 Home equity loans and lines of credit ​ ​ 11 ​ ​ — ​ ​ 11 Consumer and other ​ ​ 170 ​ ​ — ​ ​ 170 Total Nonaccrual Loans and Leases ​ $ 1,211 ​ $ 1,049 ​ $ 2,260 ​ All payments received while on nonaccrual status are applied against the principal balance of the loan. ​ When a mortgage loan becomes seriously delinquent ( 90 days 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 four months 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 amortized cost basis of collateral-dependent loans, excluding accrued interest receivable, was $87,000 and $227,000 at March 31, 2024 and December 31, 2023, respectively. These loans were collateralized by residential real estate in Hawaii. As of March 31, 2024 and December 31, 2023, the fair value of the collateral less selling costs of these collateral-dependent loans exceeded the amortized cost basis. There was no ACL on collateral-dependent loans. ​ The Company had no real estate owned as of March 31, 2024 or December 31, 2023. There was in the process of foreclosure at March 31, 2024. There were ​ Nearly all of our 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 three months ended March 31, 2023, the Company sold mortgage loans held for sale with principal balances of $360,000 and recognized a gain of $1,000 . The Company did not sell any mortgage loans in the three months ended March 31, 2024. The Company had ​ The Company serviced loans for others with principal balances of $32.6 million at March 31, 2024 and $33.2 million at December 31, 2023. Of these amounts, million of loan balances relate to securitizations for which the Company continues to hold the related mortgage-backed securities at March 31, 2024 and December 31, 2023, respectively. The amount of contractually specified servicing fees earned for the three months ended March 31, 2024 and 2023 was , respectively. The fees are reported in service and other fees in the Consolidated Statements of Income. ​

Advances from the Federal Home

Advances from the Federal Home Loan Bank	3 Months Ended
	Mar. 31, 2024
Advances from the Federal Home Loan Bank
Advances from the Federal Home Loan Bank	(7) 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 March 31, 2024 and December 31, 2023, our credit limit with the FHLB of Des Moines was equal to 45% of Territorial Savings Bank’s total assets and we had the capacity to borrow an additional $613.1 million and $612.6 million, respectively. ​ Advances outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 Weighted ​ Weighted Average ​ Average (Dollars in thousands) Amount Rate Amount Rate Due within one year ​ $ 82,000 1.40 % ​ $ 82,000 1.40 % Due over 1 year to 2 years ​ 45,000 2.87 ​ ​ 45,000 2.87 ​ Due over 2 years to 3 years ​ 40,000 3.70 ​ ​ 20,000 3.20 ​ Due over 3 years to 4 years ​ ​ 35,000 ​ 4.22 ​ ​ ​ 30,000 ​ 4.24 ​ Due over 4 years to 5 years ​ ​ 40,000 ​ 4.41 ​ ​ ​ 60,000 ​ 4.32 ​ Due over 5 years to 6 years ​ — — ​ ​ 5,000 4.38 ​ Total ​ $ 242,000 2.96 % ​ $ 242,000 2.96 % ​

Advances from the Federal Reser

Advances from the Federal Reserve Bank	3 Months Ended
	Mar. 31, 2024
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract]
Federal Reserve Bank Advances, Disclosure [Text Block]	​ In March 2023, the FRB created a new Bank Term Funding Program (BTFP) to make additional funding available to eligible depository institutions. The BTFP ceased making new loans on March 11, 2024. This program offered loans up to a one year term that can be prepaid without penalty. The amount that could be borrowed was based upon the par value of the securities pledged as collateral to the FRB. ​ Advances outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 Weighted ​ Weighted Average ​ Average (Dollars in thousands) Amount Rate Amount Rate Due within one year ​ $ 50,000 4.76 % ​ $ 50,000 4.89 % Total ​ $ 50,000 ​ 4.76 % ​ $ 50,000 ​ 4.89 % ​

Securities Sold Under Agreement

Securities Sold Under Agreements to Repurchase	3 Months Ended
	Mar. 31, 2024
Securities Sold Under Agreements to Repurchase
Securities Sold Under Agreements to Repurchase	(9) 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ Weighted ​ Weighted ​ Repurchase Average ​ Repurchase Average ​ (Dollars in thousands) Liability Rate Liability Rate ​ Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 1 year or less ​ $ 10,000 1.81 % ​ $ 5,000 1.88 % ​ Over 1 year to 2 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 March 31, 2024. 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 fair value of the securities pledged must exceed the repurchase liability by 5.00%. 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 ​ $ 14,046 ​ $ 11,758 ​ $ 10,000 ​ $ 4,046 9 ​ ​

Offsetting of Financial Liabili

Offsetting of Financial Liabilities	3 Months Ended
	Mar. 31, 2024
Offsetting of Financial Liabilities
Offsetting of Financial Liabilities	(10) Offsetting of Financial Liabilities ​ Securities sold under agreements to repurchase are subject to a right of offset in the event of default. See Note 9, 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 March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​

Employee Stock Ownership Plan

Employee Stock Ownership Plan	3 Months Ended
	Mar. 31, 2024
Employee Stock Ownership Plan
Employee Stock Ownership Plan
Employee Stock Ownership Plan	(11) 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 prime rate, as published in 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 three months ended March 31, 2024 and 2023 amounted to , respectively. ​ Shares held by the ESOP trust were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, 2024 2023 Allocated shares ​ 632,172 ​ 619,938 ​ ​ Unearned shares ​ 232,431 ​ 244,665 ​ ​ Total ESOP shares ​ 864,603 ​ 864,603 ​ ​ Fair value of unearned shares, in thousands ​ $ 1,873 ​ $ 2,728 ​ ​ ​ The ESOP restoration plan is a nonqualified 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 three months ended March 31, 2024 and 2023, we accrued ​

Share-Based Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2024
2010 Equity Incentive Plan
Share-Based Compensation
Share-Based Compensation	(12) 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. The cost of the awards will be recognized on a straight-line basis over the three -year vesting period during which participants are required to provide services in exchange for the awards. There are 42,680 remaining shares available for new awards under the 2019 Equity Plan. ​ 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 Operations 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) 2024 2023 Compensation expense ​ $ 81 ​ $ (42) ​ Income tax benefit ​ 22 ​ (11) ​ ​ Share-based compensation expense and the income tax benefit had credit balances during the three months ended March 31, 2023. The credit balances occurred when the number of performance-based restricted stock units (PRSUs), which are based on a performance condition, decreased because the Company’s three-year return on average equity declined in comparison to a peer group of banks. ​ Restricted Stock ​ Restricted stock awards are accounted for as fixed grants 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 are 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 nonforfeitable 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 Time-Based Average Grant Restricted Date Fair Stock Value Unvested at December 31, 2023 25,738 ​ $ 21.61 ​ Granted — ​ — ​ Vested — ​ — ​ Forfeited — ​ — ​ Unvested at March 31, 2024 25,738 ​ $ 21.61 ​ ​ ​ ​ ​ ​ ​ ​ Unvested at December 31, 2022 23,664 ​ $ 24.15 ​ Granted — ​ — ​ Vested 4,540 ​ 21.05 ​ Forfeited — ​ — ​ Unvested at March 31, 2023 19,124 ​ $ 24.89 ​ ​ As of March 31, 2024, the Company had $288,000 of unrecognized compensation costs related to time-based restricted stock. ​ The table below presents the 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, 2023 44,967 ​ $ 22.85 Granted — ​ — Vested — ​ — Forfeited 12,797 ​ 26.77 Unvested at March 31, 2024 32,170 ​ $ 21.30 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2022 43,557 ​ $ 23.63 Granted — ​ — Vested — ​ — Forfeited 16,348 ​ 21.05 Unvested at March 31, 2023 27,209 ​ $ 25.18 ​ The fair value of these PRSUs is based on the fair value of the Company’s stock on the date of grant. As of March 31, 2024, the Company had no unrecognized compensation costs related to these PRSUs since meeting the performance condition is not probable. Compensation expense up to $457,000 may be recognized in the future if achievement of the performance condition becomes probable. Performance will be measured over a three-year performance period and will be cliff vested. The performance condition is measured quarterly by comparing the Company’s three-year return on average equity to a peer group of banks. The Company’s percentile ranking in the peer group is used to adjust the number of PRSUs that are expected to vest. ​ 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, 2023 11,245 ​ $ 22.31 Granted — ​ ​ — Vested — ​ — Forfeited 3,199 ​ 26.00 Unvested at March 31, 2024 8,046 ​ $ 20.85 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2022 10,889 ​ $ 24.04 Granted — ​ ​ — Vested — ​ — Forfeited 4,087 ​ 22.16 Unvested at March 31, 2023 6,802 ​ $ 25.16 ​ As of March 31, 2024, the Company had $50,000 of unrecognized compensation costs related to the PRSUs that are based on a market condition. The market value of PRSUs that will vest on a market condition is determined by a Monte Carlo valuation of the Company’s stock as of the grant date. Performance will be measured over a three-year performance period 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.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2024
Earnings Per Share
Earnings Per Share	(13) Earnings Per Share ​ Holders of unvested restricted stock accrue 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 and 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. ​ The table below presents the information used to compute basic and diluted earnings per share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ (Dollars in thousands, except per share data) 2024 2023 Net (loss) income ​ $ (482) ​ $ 2,316 ​ ​ ​ Income allocated to participating securities ​ ​ (1) ​ ​ (19) ​ ​ ​ Net (loss) income available to common shareholders ​ $ (483) ​ $ 2,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average number of shares used in: ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share ​ 8,588,137 ​ 8,774,634 ​ ​ ​ Dilutive common stock equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ 42,582 ​ 32,110 ​ ​ ​ Diluted earnings per share ​ 8,630,719 ​ 8,806,744 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net (loss) income per common share, basic ​ $ (0.06) ​ $ 0.26 ​ ​ ​ Net (loss) income per common share, diluted ​ $ (0.06) ​ $ 0.26 ​ ​ ​ ​

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	3 Months Ended
	Mar. 31, 2024
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Loss	(14) Accumulated Other Comprehensive Loss ​ The table below presents the changes in the components of accumulated other comprehensive loss, net of taxes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unfunded Unrealized Pension Loss/(Gain) on (Dollars in thousands) Liability Securities Total Three months ended March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 4,466 ​ $ 1,755 ​ $ 6,221 ​ Other comprehensive loss, net of taxes ​ — ​ 396 ​ 396 ​ Net current period other comprehensive loss ​ — ​ 396 ​ 396 ​ Balances at end of period ​ $ 4,466 ​ $ 2,151 ​ $ 6,617 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 5,746 ​ $ 1,998 ​ $ 7,744 ​ Other comprehensive income, net of taxes ​ ​ — ​ ​ (337) ​ ​ (337) ​ Net current period other comprehensive income ​ — ​ (337) ​ (337) ​ Balances at end of period ​ $ 5,746 ​ $ 1,661 ​ $ 7,407 ​ ​ The table below presents the tax effect on each component of accumulated other comprehensive loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2024 2023 Pretax After Tax Pretax After Tax (Dollars in thousands) Amount Tax Amount Amount Tax Amount Unrealized loss (gain) on securities ​ $ 540 ​ $ (144) ​ $ 396 ​ $ (459) ​ $ 122 ​ $ (337) ​ Total ​ $ 540 ​ $ (144) ​ $ 396 ​ $ (459) ​ $ 122 ​ $ (337) ​ ​ ​

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2024
Revenue Recognition
Revenue Recognition	(15) 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 reporting 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 in other noninterest income in the Consolidated Statements of Operations. 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 Three months ended March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 240 ​ $ 40 ​ $ 280 Other revenue ​ ​ 33 ​ ​ 34 ​ ​ 67 Total ​ $ 273 ​ $ 74 ​ $ 347 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 275 ​ $ 42 ​ $ 317 Other revenue ​ ​ 35 ​ ​ 33 ​ ​ 68 Total ​ $ 310 ​ $ 75 ​ $ 385 ​

Leases

Leases	3 Months Ended
	Mar. 31, 2024
Leases
Leases	(16) Leases ​ The table below presents lease costs and other information for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ March 31, (Dollars in thousands) 2024 2023 Lease costs: ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 666 ​ $ 705 ​ Short-term lease costs ​ 163 ​ 104 ​ Variable lease costs ​ 43 ​ 43 ​ Total lease costs ​ $ 872 ​ $ 852 ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ $ 195 ​ $ 769 ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 404 ​ $ 118 ​ ​ Future minimum rental commitments under noncancellable operating leases are as follows: ​ ​ ​ ​ ​ ​ ​ March 31, (Dollars in thousands) 2024 2024 ​ $ 2,625 2025 ​ 2,228 2026 ​ 2,086 2027 ​ 2,001 2028 ​ 1,709 Thereafter ​ 8,910 Total ​ ​ 19,559 ​ ​ ​ ​ Less present value discount ​ ​ (1,962) Present value of leases ​ $ 17,597 ​ The table below presents additional lease-related information: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ March 31, ​ ​ ​ 2024 ​ 2023 ​ Weighted-average remaining lease term (years) ​ 9.76 ​ ​ 8.80 ​ ​ Weighted-average discount rate ​ ​ 2.14 % ​ ​ 2.09 % ​ ​

Fair Value

Fair Value	3 Months Ended
	Mar. 31, 2024
Fair Value
Fair Value	(17) Fair Value ​ 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 1 — Valuation is based upon quoted prices (unadjusted) for identical assets or liabilities traded in active markets. A quoted price in an active market provides the most reliable evidence of fair value and shall be used to measure fair value whenever available. ​ ● Level 2 — Valuation is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant assumptions are observable in the market. ​ ● 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, individually evaluated 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 March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 90,059 ​ $ 90,059 ​ $ 90,059 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 19,483 ​ ​ 19,483 ​ ​ — ​ ​ 19,483 ​ ​ — ​ Investment securities held to maturity ​ 677,578 ​ ​ 547,290 ​ ​ — ​ ​ 547,290 ​ ​ — ​ Loans receivable, net ​ 1,309,712 ​ ​ 1,095,737 ​ ​ — ​ ​ — ​ ​ 1,095,737 ​ FHLB stock ​ 12,232 ​ ​ 12,232 ​ ​ — ​ ​ 12,232 ​ ​ — ​ FRB stock ​ ​ 3,182 ​ ​ 3,182 ​ ​ — ​ ​ 3,182 ​ ​ — ​ Accrued interest receivable ​ 6,281 ​ ​ 6,281 ​ ​ 158 ​ ​ 1,472 ​ ​ 4,651 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,600,148 ​ ​ 1,596,514 ​ ​ — ​ ​ 1,072,875 ​ ​ 523,639 ​ Advances from the Federal Home Loan Bank ​ 242,000 ​ ​ 238,033 ​ ​ — ​ ​ 238,033 ​ ​ — ​ Advances from the Federal Reserve Bank ​ ​ 50,000 ​ ​ 49,815 ​ ​ — ​ ​ 49,815 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,755 ​ ​ — ​ ​ 9,755 ​ ​ — ​ Accrued interest payable ​ 1,285 ​ ​ 1,285 ​ ​ — ​ ​ 537 ​ ​ 748 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 126,659 ​ $ 126,659 ​ $ 126,659 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 20,171 ​ ​ 20,171 ​ ​ — ​ ​ 20,171 ​ ​ — ​ Investment securities held to maturity ​ 685,728 ​ ​ 568,128 ​ ​ — ​ ​ 568,128 ​ ​ — ​ Loans receivable, net ​ 1,303,431 ​ ​ 1,120,704 ​ ​ — ​ ​ — ​ ​ 1,120,704 ​ FHLB stock ​ 12,192 ​ ​ 12,192 ​ ​ — ​ ​ 12,192 ​ ​ — ​ FRB stock ​ ​ 3,180 ​ ​ 3,180 ​ ​ — ​ ​ 3,180 ​ ​ — ​ Accrued interest receivable ​ 6,105 ​ ​ 6,105 ​ ​ 79 ​ ​ 1,441 ​ ​ 4,585 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,636,604 ​ ​ 1,633,164 ​ ​ — ​ ​ 1,104,171 ​ ​ 528,993 ​ Advances from the Federal Home Loan Bank ​ 242,000 ​ ​ 238,380 ​ ​ — ​ ​ 238,380 ​ ​ — ​ Advances from the Federal Reserve Bank ​ ​ 50,000 ​ ​ 50,049 ​ ​ — ​ ​ 50,049 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,700 ​ ​ — ​ ​ 9,700 ​ ​ — ​ Accrued interest payable ​ 1,183 ​ ​ 1,183 ​ ​ — ​ ​ 157 ​ ​ 1,026 ​ ​ At March 31, 2024 and December 31, 2023, 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 March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment securities available for sale ​ $ — ​ $ 19,483 ​ $ — ​ $ 19,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment securities available for sale ​ $ — ​ $ 20,171 ​ $ — ​ $ 20,171 ​ ​ There were no assets or liabilities measured at fair value on a nonrecurring basis as of March 31, 2024 or December 31, 2023.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2024
Subsequent Events
Subsequent Events	(18) Subsequent Events ​ Hope Bancorp Merger Agreement ​ On April 26, 2024, Hope Bancorp, Inc., a Delaware corporation (“Hope Bancorp”), and Territorial Bancorp Inc., a Maryland corporation (“Territorial Bancorp”), entered into an Agreement and Plan of Merger (the “Merger Agreement”). Under the terms of the merger agreement, Territorial Bancorp shareholders will receive a fixed exchange ratio of ​ The transaction is subject to regulatory approvals, the approval of Territorial Bancorp shareholders, and the satisfaction of other customary closing conditions.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Summary of Significant Accounting Policies
Recently Issued Accounting Pronouncements	​ In June 2022, the Financial Accounting Standards Board (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 Federal Home Loan Bank (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 publicly traded and can only be issued, exchanged, redeemed or repurchased by the FRB and the FHLB. ASU 2022-03 was effective for fiscal years beginning after December 15, 2023. The Company adopted the standard on January 1, 2024, and it did not have a material effect on its consolidated financial statements.

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	3 Months Ended
	Mar. 31, 2024
Cash and Cash Equivalents
Schedule of balances of cash and cash equivalents	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, (Dollars in thousands) 2024 2023 Cash and due from banks ​ $ 10,714 ​ $ 10,471 ​ ​ Interest-earning deposits in other banks ​ 79,345 ​ 116,188 ​ ​ Cash and cash equivalents ​ $ 90,059 ​ $ 126,659 ​ ​

Investment Securities (Tables)

Investment Securities (Tables)	3 Months Ended
	Mar. 31, 2024
Investment Securities
Schedule of amortized cost and fair values of investment securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross Unrealized ​ Estimated ​ ​ (Dollars in thousands) Cost Gains Losses Fair Value ACL March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ 22,415 ​ $ — $ (2,932) ​ $ 19,483 ​ $ — Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ 677,578 ​ ​ 36 ​ (130,324) ​ ​ 547,290 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 699,993 ​ $ 36 $ (133,256) ​ $ 566,773 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ 22,563 ​ $ — $ (2,392) ​ $ 20,171 ​ $ — Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ 685,728 ​ ​ 68 ​ (117,668) ​ ​ 568,128 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 708,291 ​ $ 68 $ (120,060) ​ $ 588,299 ​ $ — ​
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 ​ $ 22,415 ​ $ 19,483 ​ Total ​ $ 22,415 ​ $ 19,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ Due within 5 years ​ $ 12 ​ $ 12 ​ Due after 5 years through 10 years ​ 6 ​ 6 ​ Due after 10 years ​ 677,560 ​ 547,272 ​ Total ​ $ 677,578 ​ $ 547,290 ​
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) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government-sponsored enterprises ​ $ — ​ $ — ​ $ 19,483 ​ $ (2,932) 4 ​ $ 19,483 ​ $ (2,932) ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ — ​ ​ — ​ ​ 544,088 ​ ​ (130,324) 152 ​ ​ 544,088 ​ ​ (130,324) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ — ​ $ — ​ $ 563,571 ​ $ (133,256) ​ 156 ​ $ 563,571 ​ $ (133,256) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government sponsored enterprises ​ $ — ​ $ — ​ $ 20,171 ​ $ (2,392) 4 ​ $ 20,171 ​ $ (2,392) ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage-backed securities issued by U.S. government agencies or U.S. government-sponsored enterprises ​ ​ 10,326 ​ ​ (107) ​ ​ 554,514 ​ ​ (117,561) 152 ​ ​ 564,840 ​ ​ (117,668) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 10,326 ​ $ (107) ​ $ 574,685 ​ $ (119,953) ​ 156 ​ $ 585,011 ​ $ (120,060) ​ ​

Loans Receivable and Allowanc_2

Loans Receivable and Allowance for Credit Losses (Tables)	3 Months Ended
	Mar. 31, 2024
Loans Receivable and Allowance for Credit Losses
Schedule of components of loans receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ December 31, (Dollars in thousands) 2024 2023 Real estate loans: ​ ​ ​ ​ ​ ​ First mortgages: ​ ​ ​ ​ ​ ​ One- to four-family residential ​ $ 1,275,897 ​ $ 1,277,544 Multi-family residential ​ 5,604 ​ 5,855 Construction, commercial, and other ​ 12,554 ​ 11,631 Home equity loans and lines of credit ​ 9,219 ​ 7,058 Total real estate loans ​ 1,303,274 ​ 1,302,088 Other loans: ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ 180 ​ 196 Consumer and other loans ​ 8,305 ​ 8,257 Total other loans ​ ​ 8,485 ​ ​ 8,453 ​ ​ ​ ​ ​ ​ ​ Total loans ​ 1,311,759 ​ 1,310,541 ​ ​ ​ ​ ​ ​ ​ Net unearned fees and discounts ​ (2,047) ​ (1,989) Total loans, net of unearned fees and discounts ​ 1,309,712 ​ 1,308,552 ​ ​ ​ ​ ​ ​ ​ Allowance for credit losses ​ (5,142) ​ (5,121) Loans receivable, net of allowance for credit losses ​ $ 1,304,570 ​ $ 1,303,431
Schedule of activity in allowance for loan losses on loans receivable and by portfolio segment	The table below presents the activity in the allowance for credit losses by portfolio segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Commercial Consumer ​ (Dollars in thousands) Estate Loans Loans ​ Unallocated Totals Three months ended March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 4,502 ​ $ 514 ​ $ 105 ​ $ — ​ $ 5,121 (Reversal of provision) provision for credit losses ​ (26) ​ ​ 12 ​ ​ 33 ​ ​ — ​ 19 ​ ​ 4,476 ​ 526 ​ 138 ​ — ​ 5,140 Charge-offs ​ (2) ​ ​ — ​ ​ (6) ​ ​ — ​ (8) Recoveries ​ 9 ​ ​ — ​ ​ 1 ​ ​ — ​ 10 Net recoveries (charge-offs) ​ 7 ​ — ​ (5) ​ — ​ 2 Balance, end of period ​ $ 4,483 ​ $ 526 ​ $ 133 ​ $ — ​ $ 5,142 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,263 ​ $ 434 ​ $ 76 ​ $ 259 ​ $ 2,032 Adoption of ASU No. 2016-13 ​ ​ 3,393 ​ ​ 71 ​ ​ 4 ​ ​ (259) ​ ​ 3,209 (Reversal of provision) provision for credit losses ​ (27) ​ ​ (88) ​ ​ 15 ​ ​ — ​ (100) ​ ​ 4,629 ​ 417 ​ 95 ​ — ​ 5,141 Charge-offs ​ — ​ — ​ (15) ​ — ​ (15) Recoveries ​ — ​ — ​ 1 ​ — ​ 1 Net charge-offs ​ — ​ — ​ (14) ​ — ​ (14) Balance, end of period ​ $ 4,629 ​ $ 417 ​ $ 81 ​ $ — ​ $ 5,127 ​
Schedule of credit quality indicator by loan class and year.	The Company primarily uses the aging of loans to monitor the credit quality of its loan portfolio. The table below presents by credit quality indicator, loan class, and year of origination, the amortized cost basis of the Company’s loans as of March 31, 2024. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revolving Loans ​ ​ ​ ​ Amortized Cost of Term Loans by Origination Year ​ Amortized ​ ​ ​ (Dollars in thousands) ​ 2024 ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ Prior ​ Cost Basis ​ Total March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Loans not past due ​ ​ 55 ​ ​ 613 ​ ​ 336 ​ ​ 4,797 ​ ​ — ​ ​ 1,013 ​ ​ 1,236 ​ ​ 8,050 Total Commercial ​ ​ 55 ​ ​ 613 ​ ​ 336 ​ ​ 4,797 ​ ​ — ​ ​ 1,013 ​ ​ 1,236 ​ ​ 8,050 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ 9 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 9 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 170 ​ ​ 170 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 1 ​ ​ 1 Loans not past due ​ ​ 97 ​ ​ 46 ​ ​ 73 ​ ​ 13 ​ ​ 3 ​ ​ 52 ​ ​ 8,194 ​ ​ 8,478 Total Consumer ​ ​ 106 ​ ​ 46 ​ ​ 73 ​ ​ 13 ​ ​ 3 ​ ​ 52 ​ ​ 8,365 ​ ​ 8,658 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Estate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 98 ​ ​ — ​ ​ 98 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 87 ​ ​ — ​ ​ 87 Loans not past due ​ ​ 15,987 ​ ​ 90,595 ​ ​ 128,031 ​ ​ 281,382 ​ ​ 182,584 ​ ​ 594,240 ​ ​ — ​ ​ 1,292,819 Total Real Estate ​ ​ 15,987 ​ ​ 90,595 ​ ​ 128,031 ​ ​ 281,382 ​ ​ 182,584 ​ ​ 594,425 ​ ​ — ​ ​ 1,293,004 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 16,148 ​ $ 91,254 ​ $ 128,440 ​ $ 286,192 ​ $ 182,587 ​ $ 595,490 ​ $ 9,601 ​ $ 1,309,712 ​ The Company did not have any revolving loans that converted to term loans during the three months ended March 31, 2024. ​ The table below presents by credit quality indicator, loan class, and year of origination, the amortized cost basis of the Company’s loans as of December 31, 2023. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revolving Loans ​ ​ ​ ​ Amortized Cost of Term Loans by Origination Year ​ Amortized ​ ​ ​ (Dollars in thousands) ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ 2019 ​ Prior ​ Cost Basis ​ Total December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Loans not past due ​ ​ 387 ​ ​ 353 ​ ​ 4,836 ​ ​ — ​ ​ 203 ​ ​ 856 ​ ​ 1,230 ​ ​ 7,865 Total Commercial ​ ​ 387 ​ ​ 353 ​ ​ 4,836 ​ ​ — ​ ​ 203 ​ ​ 856 ​ ​ 1,230 ​ ​ 7,865 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Consumer ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ 4 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 4 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — Loans not past due ​ ​ 271 ​ ​ 80 ​ ​ 20 ​ ​ 4 ​ ​ 14 ​ ​ 42 ​ ​ 6,137 ​ ​ 6,568 Total Consumer ​ ​ 275 ​ ​ 80 ​ ​ 20 ​ ​ 4 ​ ​ 14 ​ ​ 42 ​ ​ 6,137 ​ ​ 6,572 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Real Estate ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 30 - 59 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 428 ​ ​ — ​ ​ 428 60 - 89 days past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ — 90 days or more past due ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 140 ​ ​ 87 ​ ​ — ​ ​ 227 Loans not past due ​ ​ 91,195 ​ ​ 129,148 ​ ​ 283,571 ​ ​ 183,887 ​ ​ 91,113 ​ ​ 514,546 ​ ​ — ​ ​ 1,293,460 Total Real Estate ​ ​ 91,195 ​ ​ 129,148 ​ ​ 283,571 ​ ​ 183,887 ​ ​ 91,253 ​ ​ 515,061 ​ ​ — ​ ​ 1,294,115 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 91,857 ​ $ 129,581 ​ $ 288,427 ​ $ 183,891 ​ $ 91,470 ​ $ 515,959 ​ $ 7,367 ​ $ 1,308,552
Schedule of gross charge offs by loan class and year of origination	The following table presents by loan class and year of origination, the gross charge-offs recorded during the three months ended March 31, 2024 and 2023. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2024 ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ Prior ​ Total Three months ended March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ 2 ​ $ 2 Loans on deposit accounts ​ ​ — ​ ​ 3 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 3 Consumer and other ​ ​ — ​ ​ 3 ​ ​ — ​ ​ — ​ ​ — ​ ​ — ​ ​ 3 Total ​ $ — ​ $ 6 ​ $ — ​ $ — ​ $ — ​ $ 2 ​ $ 8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ 2023 ​ 2022 ​ 2021 ​ 2020 ​ 2019 ​ Prior ​ Total Three months ended March 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ $ 15 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — Total ​ $ 15 ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ —
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 March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 98 ​ $ — ​ $ 87 ​ $ 185 ​ $ 1,273,726 ​ $ 1,273,911 ​ $ 2,026 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 5,597 ​ 5,597 ​ — ​ — ​ Construction, commercial, and other mortgages ​ — ​ — ​ — ​ — ​ 12,493 ​ 12,493 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 9,221 ​ 9,221 ​ 9 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 180 ​ 180 ​ — ​ — ​ Consumer and other ​ 9 ​ 170 ​ 1 ​ 180 ​ 8,130 ​ 8,310 ​ 170 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 107 ​ $ 170 ​ $ 88 ​ $ 365 ​ $ 1,309,347 ​ $ 1,309,712 ​ $ 2,205 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 428 ​ $ — ​ $ 227 ​ $ 655 ​ $ 1,274,960 ​ $ 1,275,615 ​ $ 2,079 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 5,848 ​ 5,848 ​ — ​ — ​ Construction, commercial, and other mortgages ​ — ​ — ​ — ​ — ​ 11,570 ​ 11,570 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ — ​ — ​ — ​ 7,060 ​ 7,060 ​ 11 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 196 ​ 196 ​ — ​ — ​ Consumer and other ​ 4 ​ — ​ — ​ 4 ​ 8,259 ​ 8,263 ​ 170 ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 432 ​ $ — ​ $ 227 ​ $ 659 ​ $ 1,307,893 ​ $ 1,308,552 ​ $ 2,260 ​ $ — ​
Schedule of amortized cost basis of loans on nonaccrual status	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Nonaccrual Loans With a Related ACL Nonaccrual Loans Without a Related ACL Total Nonaccrual Loans March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,535 ​ $ 491 ​ $ 2,026 Home equity loans and lines of credit ​ ​ 9 ​ ​ — ​ ​ 9 Consumer and other ​ ​ 170 ​ ​ — ​ ​ 170 Total Nonaccrual Loans and Leases ​ $ 1,714 ​ $ 491 ​ $ 2,205 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,030 ​ $ 1,049 ​ $ 2,079 Home equity loans and lines of credit ​ ​ 11 ​ ​ — ​ ​ 11 Consumer and other ​ ​ 170 ​ ​ — ​ ​ 170 Total Nonaccrual Loans and Leases ​ $ 1,211 ​ $ 1,049 ​ $ 2,260

Advances from the Federal Hom_2

Advances from the Federal Home Loan Bank (Tables)	3 Months Ended
	Mar. 31, 2024
Advances from the Federal Home Loan Bank
Schedule of advances outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 Weighted ​ Weighted Average ​ Average (Dollars in thousands) Amount Rate Amount Rate Due within one year ​ $ 82,000 1.40 % ​ $ 82,000 1.40 % Due over 1 year to 2 years ​ 45,000 2.87 ​ ​ 45,000 2.87 ​ Due over 2 years to 3 years ​ 40,000 3.70 ​ ​ 20,000 3.20 ​ Due over 3 years to 4 years ​ ​ 35,000 ​ 4.22 ​ ​ ​ 30,000 ​ 4.24 ​ Due over 4 years to 5 years ​ ​ 40,000 ​ 4.41 ​ ​ ​ 60,000 ​ 4.32 ​ Due over 5 years to 6 years ​ — — ​ ​ 5,000 4.38 ​ Total ​ $ 242,000 2.96 % ​ $ 242,000 2.96 % ​

Advances from the Federal Res_2

Advances from the Federal Reserve Bank (Tables)	3 Months Ended
	Mar. 31, 2024
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract]
Schedule of BTFP advances outstanding	Advances outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 Weighted ​ Weighted Average ​ Average (Dollars in thousands) Amount Rate Amount Rate Due within one year ​ $ 50,000 4.76 % ​ $ 50,000 4.89 % Total ​ $ 50,000 ​ 4.76 % ​ $ 50,000 ​ 4.89 % ​

Securities Sold Under Agreeme_2

Securities Sold Under Agreements to Repurchase (Tables)	3 Months Ended
	Mar. 31, 2024
Securities Sold Under Agreements to Repurchase
Summary of securities sold under agreements to repurchase	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2024 ​ December 31, 2023 ​ Weighted ​ Weighted ​ Repurchase Average ​ Repurchase Average ​ (Dollars in thousands) Liability Rate Liability Rate ​ Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 1 year or less ​ $ 10,000 1.81 % ​ $ 5,000 1.88 % ​ Over 1 year to 2 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 ​ $ 14,046 ​ $ 11,758 ​ $ 10,000 ​ $ 4,046 9 ​ ​

Offsetting of Financial Liabi_2

Offsetting of Financial Liabilities (Tables)	3 Months Ended
	Mar. 31, 2024
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 March 31, 2024: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​

Employee Stock Ownership Plan (

Employee Stock Ownership Plan (Tables)	3 Months Ended
	Mar. 31, 2024
Employee Stock Ownership Plan.
Schedule of shares held by the ESOP trust	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, December 31, 2024 2023 Allocated shares ​ 632,172 ​ 619,938 ​ ​ Unearned shares ​ 232,431 ​ 244,665 ​ ​ Total ESOP shares ​ 864,603 ​ 864,603 ​ ​ Fair value of unearned shares, in thousands ​ $ 1,873 ​ $ 2,728 ​ ​

Share-Based Compensation (Table

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2024
Schedule of compensation expense and related tax benefit for all share-based awards	​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, (Dollars in thousands) 2024 2023 Compensation expense ​ $ 81 ​ $ (42) ​ Income tax benefit ​ 22 ​ (11) ​
Restricted Stock
Schedule of restricted stock award activity	​ ​ ​ ​ ​ ​ ​ ​ Weighted Time-Based Average Grant Restricted Date Fair Stock Value Unvested at December 31, 2023 25,738 ​ $ 21.61 ​ Granted — ​ — ​ Vested — ​ — ​ Forfeited — ​ — ​ Unvested at March 31, 2024 25,738 ​ $ 21.61 ​ ​ ​ ​ ​ ​ ​ ​ Unvested at December 31, 2022 23,664 ​ $ 24.15 ​ Granted — ​ — ​ Vested 4,540 ​ 21.05 ​ Forfeited — ​ — ​ Unvested at March 31, 2023 19,124 ​ $ 24.89 ​
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, 2023 44,967 ​ $ 22.85 Granted — ​ — Vested — ​ — Forfeited 12,797 ​ 26.77 Unvested at March 31, 2024 32,170 ​ $ 21.30 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2022 43,557 ​ $ 23.63 Granted — ​ — Vested — ​ — Forfeited 16,348 ​ 21.05 Unvested at March 31, 2023 27,209 ​ $ 25.18
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, 2023 11,245 ​ $ 22.31 Granted — ​ ​ — Vested — ​ — Forfeited 3,199 ​ 26.00 Unvested at March 31, 2024 8,046 ​ $ 20.85 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2022 10,889 ​ $ 24.04 Granted — ​ ​ — Vested — ​ — Forfeited 4,087 ​ 22.16 Unvested at March 31, 2023 6,802 ​ $ 25.16

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2024
Earnings Per Share
Schedule of information used to compute basic and diluted earnings per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ (Dollars in thousands, except per share data) 2024 2023 Net (loss) income ​ $ (482) ​ $ 2,316 ​ ​ ​ Income allocated to participating securities ​ ​ (1) ​ ​ (19) ​ ​ ​ Net (loss) income available to common shareholders ​ $ (483) ​ $ 2,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average number of shares used in: ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share ​ 8,588,137 ​ 8,774,634 ​ ​ ​ Dilutive common stock equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ 42,582 ​ 32,110 ​ ​ ​ Diluted earnings per share ​ 8,630,719 ​ 8,806,744 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net (loss) income per common share, basic ​ $ (0.06) ​ $ 0.26 ​ ​ ​ Net (loss) income per common share, diluted ​ $ (0.06) ​ $ 0.26 ​ ​ ​ ​

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	3 Months Ended
	Mar. 31, 2024
Accumulated Other Comprehensive Loss
Schedule of changes in components of accumulated other comprehensive loss, net of taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unfunded Unrealized Pension Loss/(Gain) on (Dollars in thousands) Liability Securities Total Three months ended March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 4,466 ​ $ 1,755 ​ $ 6,221 ​ Other comprehensive loss, net of taxes ​ — ​ 396 ​ 396 ​ Net current period other comprehensive loss ​ — ​ 396 ​ 396 ​ Balances at end of period ​ $ 4,466 ​ $ 2,151 ​ $ 6,617 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 5,746 ​ $ 1,998 ​ $ 7,744 ​ Other comprehensive income, net of taxes ​ ​ — ​ ​ (337) ​ ​ (337) ​ Net current period other comprehensive income ​ — ​ (337) ​ (337) ​ Balances at end of period ​ $ 5,746 ​ $ 1,661 ​ $ 7,407 ​
Schedule of tax effect on each component of accumulated other comprehensive loss	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2024 2023 Pretax After Tax Pretax After Tax (Dollars in thousands) Amount Tax Amount Amount Tax Amount Unrealized loss (gain) on securities ​ $ 540 ​ $ (144) ​ $ 396 ​ $ (459) ​ $ 122 ​ $ (337) ​ Total ​ $ 540 ​ $ (144) ​ $ 396 ​ $ (459) ​ $ 122 ​ $ (337) ​ ​

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 31, 2024
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 Three months ended March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 240 ​ $ 40 ​ $ 280 Other revenue ​ ​ 33 ​ ​ 34 ​ ​ 67 Total ​ $ 273 ​ $ 74 ​ $ 347 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended March 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 275 ​ $ 42 ​ $ 317 Other revenue ​ ​ 35 ​ ​ 33 ​ ​ 68 Total ​ $ 310 ​ $ 75 ​ $ 385 ​

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2024
Leases
Schedule of lease costs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ March 31, (Dollars in thousands) 2024 2023 Lease costs: ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 666 ​ $ 705 ​ Short-term lease costs ​ 163 ​ 104 ​ Variable lease costs ​ 43 ​ 43 ​ Total lease costs ​ $ 872 ​ $ 852 ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ $ 195 ​ $ 769 ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 404 ​ $ 118 ​ ​
Schedule of future minimum rental commitments under noncancellable operating leases and lease payment obligations	​ ​ ​ ​ ​ ​ ​ March 31, (Dollars in thousands) 2024 2024 ​ $ 2,625 2025 ​ 2,228 2026 ​ 2,086 2027 ​ 2,001 2028 ​ 1,709 Thereafter ​ 8,910 Total ​ ​ 19,559 ​ ​ ​ ​ Less present value discount ​ ​ (1,962) Present value of leases ​ $ 17,597 ​
Schedule of other lease related information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, ​ ​ March 31, ​ ​ ​ 2024 ​ 2023 ​ Weighted-average remaining lease term (years) ​ 9.76 ​ ​ 8.80 ​ ​ Weighted-average discount rate ​ ​ 2.14 % ​ ​ 2.09 % ​ ​

Fair Value of Financial Instrum

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2024
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 March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 90,059 ​ $ 90,059 ​ $ 90,059 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 19,483 ​ ​ 19,483 ​ ​ — ​ ​ 19,483 ​ ​ — ​ Investment securities held to maturity ​ 677,578 ​ ​ 547,290 ​ ​ — ​ ​ 547,290 ​ ​ — ​ Loans receivable, net ​ 1,309,712 ​ ​ 1,095,737 ​ ​ — ​ ​ — ​ ​ 1,095,737 ​ FHLB stock ​ 12,232 ​ ​ 12,232 ​ ​ — ​ ​ 12,232 ​ ​ — ​ FRB stock ​ ​ 3,182 ​ ​ 3,182 ​ ​ — ​ ​ 3,182 ​ ​ — ​ Accrued interest receivable ​ 6,281 ​ ​ 6,281 ​ ​ 158 ​ ​ 1,472 ​ ​ 4,651 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,600,148 ​ ​ 1,596,514 ​ ​ — ​ ​ 1,072,875 ​ ​ 523,639 ​ Advances from the Federal Home Loan Bank ​ 242,000 ​ ​ 238,033 ​ ​ — ​ ​ 238,033 ​ ​ — ​ Advances from the Federal Reserve Bank ​ ​ 50,000 ​ ​ 49,815 ​ ​ — ​ ​ 49,815 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,755 ​ ​ — ​ ​ 9,755 ​ ​ — ​ Accrued interest payable ​ 1,285 ​ ​ 1,285 ​ ​ — ​ ​ 537 ​ ​ 748 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 126,659 ​ $ 126,659 ​ $ 126,659 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 20,171 ​ ​ 20,171 ​ ​ — ​ ​ 20,171 ​ ​ — ​ Investment securities held to maturity ​ 685,728 ​ ​ 568,128 ​ ​ — ​ ​ 568,128 ​ ​ — ​ Loans receivable, net ​ 1,303,431 ​ ​ 1,120,704 ​ ​ — ​ ​ — ​ ​ 1,120,704 ​ FHLB stock ​ 12,192 ​ ​ 12,192 ​ ​ — ​ ​ 12,192 ​ ​ — ​ FRB stock ​ ​ 3,180 ​ ​ 3,180 ​ ​ — ​ ​ 3,180 ​ ​ — ​ Accrued interest receivable ​ 6,105 ​ ​ 6,105 ​ ​ 79 ​ ​ 1,441 ​ ​ 4,585 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,636,604 ​ ​ 1,633,164 ​ ​ — ​ ​ 1,104,171 ​ ​ 528,993 ​ Advances from the Federal Home Loan Bank ​ 242,000 ​ ​ 238,380 ​ ​ — ​ ​ 238,380 ​ ​ — ​ Advances from the Federal Reserve Bank ​ ​ 50,000 ​ ​ 50,049 ​ ​ — ​ ​ 50,049 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,700 ​ ​ — ​ ​ 9,700 ​ ​ — ​ Accrued interest payable ​ 1,183 ​ ​ 1,183 ​ ​ — ​ ​ 157 ​ ​ 1,026 ​
Schedule of assets and liabilities measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Level 1 Level 2 Level 3 Total March 31, 2024 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment securities available for sale ​ $ — ​ $ 19,483 ​ $ — ​ $ 19,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investment securities available for sale ​ $ — ​ $ 20,171 ​ $ — ​ $ 20,171 ​

Organization - Narrative (Detai

Organization - Narrative (Details)	3 Months Ended
	Mar. 31, 2024 subsidiary
Organization
Number of inactive subsidiaries	1

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Allowance of Credit Losses (ACL) on Loans and Securities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Summary of Significant Accounting Policies
Financing receivable accrued interest after allowance for credit loss	$ 4.7	$ 4.6
Reserve for off-balance sheet credit exposure	0
ACL	$ 0

Cash and Cash Equivalents (Deta

Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Cash and Cash Equivalents
Cash and due from banks	$ 10,714	$ 10,471
Interest-earning deposits in other banks	79,345	116,188
Cash and cash equivalents	$ 90,059	$ 126,659

Investment Securities - Amortiz

Investment Securities - Amortized Cost and Fair Values of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Available-for-Sale [Abstract]
Amortized Cost	$ 22,415
Estimated Fair Value	19,483	$ 20,171
ACL	0
Debt Securities, Held-to-Maturity, Maturity [Abstract]
Amortized Cost	677,578	685,728
Estimated Fair Value	547,290		$ 547,290	$ 568,128
Debt Securities, Available-for-Sale and Held-to-Maturity, after Allowance for Credit Loss [Abstract]
Total Amortized Cost	699,993	708,291
Total Gross Unrealized Gains	36	68
Total Gross Unrealized Losses	(133,256)	(120,060)
Total Estimated Fair Value	566,773	588,299
U.S. government-sponsored mortgage-backed securities
Available-for-Sale [Abstract]
Amortized Cost	22,415	22,563
Gross Unrealized Losses	(2,932)	(2,392)
Estimated Fair Value	19,483	20,171
Debt Securities, Held-to-Maturity, Maturity [Abstract]
Amortized Cost	677,578	685,728
Gross Unrealized Gains	36	68
Gross Unrealized Losses	(130,324)	(117,668)
Estimated Fair Value	$ 547,290	$ 568,128

Investment Securities - Maturit

Investment Securities - Maturity Schedule of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Amortized Cost
Due after 10 years	$ 22,415
Amortized Cost	22,415
Estimated Fair Value
Due after 10 years	19,483
Estimated Fair Value	$ 19,483	$ 20,171

Investment Securities - Matur_2

Investment Securities - Maturity Schedule of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Held-to-maturity, Amortized Cost
Due within 5 years	$ 12
Due after 5 years through 10 years	6
Due after 10 years	677,560
Amortized Cost	677,578	$ 685,728
Held-to-maturity, Estimated Fair Value
Due within 5 years	12
Due after 5 years through 10 years	6
Due after 10 years	547,272
Estimated Fair Value	$ 547,290		$ 547,290	$ 568,128

Investment Securities - Securit

Investment Securities - Securities Pledged (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Realized gains and losses and the proceeds from sales of securities
Amortized cost	$ 677,578	$ 685,728
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] | Deposits [Member]
Realized gains and losses and the proceeds from sales of securities
Amortized cost	$ 549,700	555,800
Asset Pledged as Collateral with Right [Member] | Federal Reserve Bank discount window [Member]
Realized gains and losses and the proceeds from sales of securities
Amortized cost	220,900	74,000
Asset Pledged as Collateral with Right [Member] | Federal Reserve Bank Bank Term Funding Program [Member]
Realized gains and losses and the proceeds from sales of securities
Amortized cost	$ 52,600	$ 202,100

Investment Securities - Summary

Investment Securities - Summary of Investment Securities In Unrealized Loss Position Summary (Details) $ in Thousands	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($) security
Debt Securities, Held-to-Maturity, Maturity [Abstract]
Less Than 12 Months Fair Value		$ 10,326
Less Than 12 Months Unrealized Losses		(107)
12 Months or Longer Fair Value	$ 544,088	$ 554,514
Total Number of Securities	152	152
12 Months or Longer Unrealized Losses	$ (130,324)	$ (117,561)
Total Fair Value	544,088	564,840
Total Unrealized Losses	$ (130,324)	$ (117,668)

Loans Receivable and Allowanc_3

Loans Receivable and Allowance for Credit Losses - Components (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Components of loans receivable, net of allowance for credit losses
Net unearned fees and discounts	$ (2,047)	$ (1,989)
Total loans, net of unearned fees and discounts	1,309,712	1,308,552
Allowance for credit/loan losses	(5,142)	(5,121)	$ (5,127)	$ (2,032)
Loans receivable, net of allowance for credit losses	1,304,570	1,303,431
Other Financing Receivables
Components of loans receivable, net of allowance for credit losses
Total loans	8,485	8,453
Unallocated
Components of loans receivable, net of allowance for credit losses
Allowance for credit/loan losses				$ (259)
Real estate loans
Components of loans receivable, net of allowance for credit losses
Total loans	1,303,274	1,302,088
Real estate loans | One- to four-family residential
Components of loans receivable, net of allowance for credit losses
Total loans	1,275,897	1,277,544
Real estate loans | Multi-family residential
Components of loans receivable, net of allowance for credit losses
Total loans	5,604	5,855
Real estate loans | Construction, Commercial and Other Mortgage Loans
Components of loans receivable, net of allowance for credit losses
Total loans	12,554	11,631
Real estate loans | Home Equity Loans and Lines of Credit
Components of loans receivable, net of allowance for credit losses
Total loans	9,219	7,058
Other loans | Loans on Deposit Accounts
Components of loans receivable, net of allowance for credit losses
Total loans	180	196
Other loans | Consumer and other
Components of loans receivable, net of allowance for credit losses
Total loans	$ 8,305	$ 8,257

Loans Receivable and Allowanc_4

Loans Receivable and Allowance for Credit Losses - Activity in Allowance for Loan Losses by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2023
Activity in allowance for loan losses
Balance, beginning of period	$ 5,121	$ 2,032	$ 2,032		$ 2,032
(Reversal of provision) provision for credit losses	19	(100)	19
Allowance for loan losses on loans receivable after (reversal of provision) provision for loan losses	5,140	5,141
Charge-offs	(8)	(15)
Recoveries	10	1
Net charge-offs	2	(14)
Balance, end of period	5,142	5,127			5,121
Activity in allowance for loan losses, prior adoption
(Reversal of provision) provision for loan losses				$ (100)
Adoption of ASU No. 2016-13 | Accounting Standards Update 2016-13 [Member]
Activity in allowance for loan losses
Balance, end of period		3,209
Real Estate
Activity in allowance for loan losses
Balance, beginning of period	4,502	1,263	1,263		1,263
(Reversal of provision) provision for credit losses	(26)	(27)
Allowance for loan losses on loans receivable after (reversal of provision) provision for loan losses	4,476	4,629
Charge-offs	(2)
Recoveries	9
Net charge-offs	7
Balance, end of period	4,483	4,629			4,502
Real Estate | Adoption of ASU No. 2016-13 | Accounting Standards Update 2016-13 [Member]
Activity in allowance for loan losses
Balance, end of period		3,393
Commercial
Activity in allowance for loan losses
Balance, beginning of period	514	434	434		434
(Reversal of provision) provision for credit losses	12	(88)
Allowance for loan losses on loans receivable after (reversal of provision) provision for loan losses	526	417
Balance, end of period	526	417			514
Commercial | Adoption of ASU No. 2016-13 | Accounting Standards Update 2016-13 [Member]
Activity in allowance for loan losses
Balance, end of period		71
Consumer
Activity in allowance for loan losses
Balance, beginning of period	105	76	76		76
(Reversal of provision) provision for credit losses	33	15
Allowance for loan losses on loans receivable after (reversal of provision) provision for loan losses	138	95
Charge-offs	(6)	(15)
Recoveries	1	1
Net charge-offs	(5)	(14)
Balance, end of period	$ 133	81			105
Consumer | Adoption of ASU No. 2016-13 | Accounting Standards Update 2016-13 [Member]
Activity in allowance for loan losses
Balance, end of period		4
Unallocated
Activity in allowance for loan losses
Balance, beginning of period		259	$ 259		$ 259
Unallocated | Adoption of ASU No. 2016-13 | Accounting Standards Update 2016-13 [Member]
Activity in allowance for loan losses
Balance, end of period		$ (259)

Loans Receivable and Allowanc_5

Loans Receivable and Allowance for Credit Losses - Allowance for Loan Losses and Loans, Net of Unearned Fees and Discounts, by Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Allowance for loan losses:
Total ending allowance balance	$ 5,142	$ 5,121	$ 5,127	$ 2,032
Loans:
Total ending loan balance	$ 1,309,712	$ 1,308,552
Unallocated
Allowance for loan losses:
Total ending allowance balance				$ 259

Loans Receivable and Allowanc_6

Loans Receivable and Allowance for Credit Losses - Impaired Loans by Class (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Impaired Financing Receivable 1 [Line Items]
Charge offs	$ 8	$ 15
Year 2023
Impaired Financing Receivable 1 [Line Items]
Charge offs	6		$ 15
Prior years
Impaired Financing Receivable 1 [Line Items]
Charge offs	2
One- to four-family residential
Impaired Financing Receivable 1 [Line Items]
Charge offs	2
One- to four-family residential | Prior years
Impaired Financing Receivable 1 [Line Items]
Charge offs	2
Loans on Deposit Accounts
Impaired Financing Receivable 1 [Line Items]
Charge offs	3
Loans on Deposit Accounts | Year 2023
Impaired Financing Receivable 1 [Line Items]
Charge offs	3		$ 15
Consumer and other
Impaired Financing Receivable 1 [Line Items]
Charge offs	3
Consumer and other | Year 2023
Impaired Financing Receivable 1 [Line Items]
Charge offs	$ 3

Loans Receivable and Allowanc_7

Loans Receivable and Allowance for Credit Losses - Amortized Cost by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Recorded Investment, Past Due
2024	$ 16,148	$ 91,857
2023	91,254	129,581
2022	128,440	288,427
2021	286,192	183,891
2020	182,587	91,470
Prior	595,490	515,959
Revolving Loans Amortized Cost Basis	9,601	7,367
Total	1,309,712	1,308,552
Commercial
Financing Receivable, Recorded Investment, Past Due
2024	55	387
2023	613	353
2022	336	4,836
2021	4,797
2020		203
Prior	1,013	856
Revolving Loans Amortized Cost Basis	1,236	1,230
Total	8,050	7,865
Consumer
Financing Receivable, Recorded Investment, Past Due
2024	106	275
2023	46	80
2022	73	20
2021	13	4
2020	3	14
Prior	52	42
Revolving Loans Amortized Cost Basis	8,365	6,137
Total	8,658	6,572
Real Estate
Financing Receivable, Recorded Investment, Past Due
2024	15,987	91,195
2023	90,595	129,148
2022	128,031	283,571
2021	281,382	183,887
2020	182,584	91,253
Prior	594,425	515,061
Total	1,293,004	1,294,115
Not Past Due | Commercial
Financing Receivable, Recorded Investment, Past Due
2024	55	387
2023	613	353
2022	336	4,836
2021	4,797
2020		203
Prior	1,013	856
Revolving Loans Amortized Cost Basis	1,236	1,230
Total	8,050	7,865
Not Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due
2024	97	271
2023	46	80
2022	73	20
2021	13	4
2020	3	14
Prior	52	42
Revolving Loans Amortized Cost Basis	8,194	6,137
Total	8,478	6,568
Not Past Due | Real Estate
Financing Receivable, Recorded Investment, Past Due
2024	15,987	91,195
2023	90,595	129,148
2022	128,031	283,571
2021	281,382	183,887
2020	182,584	91,113
Prior	594,240	514,546
Total	1,292,819	1,293,460
30 - 59 Days Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due
2024	9	4
Total	9	4
30 - 59 Days Past Due | Real Estate
Financing Receivable, Recorded Investment, Past Due
Prior	98	428
Total	98	428
60 - 89 Days Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due
Revolving Loans Amortized Cost Basis	170
Total	170
90 Days or More Past Due | Consumer
Financing Receivable, Recorded Investment, Past Due
Revolving Loans Amortized Cost Basis	1
Total	1
90 Days or More Past Due | Real Estate
Financing Receivable, Recorded Investment, Past Due
2020		140
Prior	87	87
Total	$ 87	$ 227

Loans Receivable and Allowanc_8

Loans Receivable and Allowance for Credit Losses - Aging of Loans and Accrual Status by Class (Details) - USD ($)	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Recorded Investment, Past Due
Total Loans	$ 1,309,712,000	$ 1,308,552,000
Nonaccrual Loans	2,205,000	2,260,000
Loans 90 Days or More Past Due and Still Accruing	0	0
One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	1,273,911,000	1,275,615,000
Nonaccrual Loans	2,026,000	2,079,000
Loans 90 Days or More Past Due and Still Accruing	0	0
Multi-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	5,597,000	5,848,000
Loans 90 Days or More Past Due and Still Accruing	0	0
Construction, Commercial and Other Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans	12,493,000	11,570,000
Loans 90 Days or More Past Due and Still Accruing	0	0
Home equity loans and lines of credit
Financing Receivable, Recorded Investment, Past Due
Total Loans	9,221,000	7,060,000
Nonaccrual Loans	9,000	11,000
Loans 90 Days or More Past Due and Still Accruing	0	0
Loans on Deposit Accounts
Financing Receivable, Recorded Investment, Past Due
Total Loans	180,000	196,000
Loans 90 Days or More Past Due and Still Accruing	0	0
Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	8,310,000	8,263,000
Nonaccrual Loans	170,000	170,000
Loans 90 Days or More Past Due and Still Accruing	0	0
Not Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	1,309,347,000	1,307,893,000
Not Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	1,273,726,000	1,274,960,000
Not Past Due | Multi-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	5,597,000	5,848,000
Not Past Due | Construction, Commercial and Other Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Total Loans	12,493,000	11,570,000
Not Past Due | Home equity loans and lines of credit
Financing Receivable, Recorded Investment, Past Due
Total Loans	9,221,000	7,060,000
Not Past Due | Loans on Deposit Accounts
Financing Receivable, Recorded Investment, Past Due
Total Loans	180,000	196,000
Not Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	8,130,000	8,259,000
Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	365,000	659,000
Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	185,000	655,000
Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	180,000	4,000
30 - 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	107,000	432,000
30 - 59 Days Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	98,000	428,000
30 - 59 Days Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	9,000	4,000
60 - 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	170,000
60 - 89 Days Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	170,000
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due
Total Loans	88,000	227,000
90 Days or More Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Loans	87,000	$ 227,000
90 Days or More Past Due | Consumer and other
Financing Receivable, Recorded Investment, Past Due
Total Loans	$ 1,000

Loans Receivable and Allowanc_9

Loans Receivable and Allowance for Credit Losses - Amortized cost basis of loans on nonaccrual status (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	$ 1,714	$ 1,211
Nonaccrual loans without a related ACL	491	1,049
Total Nonaccrual Loans	2,205	2,260
Total Nonaccrual Loans	2,205	2,260
One- to four-family residential
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	1,535	1,030
Nonaccrual loans without a related ACL	491	1,049
Total Nonaccrual Loans	2,026	2,079
Total Nonaccrual Loans	2,026	2,079
Home equity loans and lines of credit
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	9	11
Total Nonaccrual Loans	9	11
Total Nonaccrual Loans	9	11
Consumer and other
Financing Receivable, Nonaccrual [Line Items]
Nonaccrual Loans with a related ACL	170	170
Total Nonaccrual Loans	170	170
Total Nonaccrual Loans	$ 170	$ 170

Loans Receivable and Allowan_10

Loans Receivable and Allowance for Credit Losses - Delinquent and Nonaccrual Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable
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
Total Loans	$ 1,309,712	$ 1,308,552
90 Days or More Past Due
Accounts, Notes, Loans and Financing Receivable
Total Loans	$ 88	$ 227

Loans Receivable and Allowan_11

Loans Receivable and Allowance for Credit Losses - Maui Wildfire (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Loans Receivable and Allowance for Credit Losses
Total Loans	$ 1,309,712	$ 1,308,552

Loans Receivable and Allowan_12

Loans Receivable and Allowance for Credit Losses - Collateral, Sales, Serviced for Others, Directors and Executive Officers (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) loan	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable
Loans serviced for others	$ 32,600,000		$ 33,200,000
Loans serviced for others, securitization for which the company continues to hold the related mortgage-backed securities	19,100,000		19,300,000
Loans serviced for others, amount of contractually specified servicing fees earned	$ 22,000		$ 23,000
Maximum
Accounts, Notes, Loans and Financing Receivable
Loan to value ratio (as a percent)	80%
Residential Mortgage Loans Held For Sale
Accounts, Notes, Loans and Financing Receivable
Number of nonaccrual loans | loan	0
Residential Mortgage
Accounts, Notes, Loans and Financing Receivable
Residential mortgage loans sold, loan amount		$ 360,000
Residential mortgage loans sold, recognized gains		$ 1,000

Loans Receivable and Allowan_13

Loans Receivable and Allowance for Credit Losses - Troubled Debt Restructurings (Details)	Mar. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($)
Additional disclosures
Real estate owned	$ 0	$ 0
Residential Mortgage
Additional disclosures
Mortgage loans in process of foreclosure, number of contracts	1	2
Mortgage loans in process of foreclosure, total value		$ 227,000
Residential Mortgage | One- to four-family residential
Additional disclosures
Mortgage loans in process of foreclosure, total value	$ 87,000

Advances from the Federal Hom_3

Advances from the Federal Home Loan Bank (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Federal Home Loan Bank advances
Federal Home Loan Bank stock, at cost	$ 12,232	$ 12,192
Federal Home Loan Bank, Advances, Rolling Maturity
Due within one year	82,000	82,000
Due over 1 year to 2 years	45,000	45,000
Due over 2 years to 3 years	40,000	20,000
Due over 3 years to 4 years	35,000	30,000
Due over 4 years to 5 years	40,000	60,000
Due over 5 years to 6 years		5,000
Total	$ 242,000	$ 242,000
Weighted Average Rate
Due within one year (as a percent)	1.40%	1.40%
Due over 1 year to 2 years (as a percent)	2.87%	2.87%
Due over 2 years to 3 years (as a percent)	3.70%	3.20%
Due over 3 years to 4 years (as a percent)	4.22%	4.24%
Due over 4 years to 5 years (as a percent)	4.41%	4.32%
Due over 5 years to 6 years (as a percent)		4.38%
Total (as a percent)	2.96%	2.96%
FHLB Des Moines
Federal Home Loan Bank advances
Available additional unused FHLB advances	$ 613,100	$ 612,600
Territorial Savings Bank | FHLB Des Moines
Federal Home Loan Bank advances
Percentage of total assets used to determine maximum line of credit		45%

Advances from the Federal Res_3

Advances from the Federal Reserve Bank (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract]
Due within one year	$ 50,000	$ 50,000
Due within one year (Weighted Average Rate)	4.76%	4.89%

Securities Sold Under Agreeme_3

Securities Sold Under Agreements to Repurchase - Summary of Repurchase Liability by Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Securities sold under agreements to repurchase
Repurchase Liability	$ 10,000	$ 10,000
Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)	1.81%	1.81%
Over 1 year to 2 years
Securities sold under agreements to repurchase
Repurchase Liability	$ 10,000	$ 5,000
Over 1 year to 2 years | Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)	1.81%	1.88%
Over 2 years to 3 years
Securities sold under agreements to repurchase
Repurchase Liability		$ 5,000
Over 2 years to 3 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) - Maturing Over 90 days $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Securities sold under agreements to repurchase
Carrying Value of Securities	$ 14,046
Fair Value of Securities	11,758
Repurchase Liability	10,000
Amount at Risk	$ 4,046
Weighted Average Months to Maturity	9 months

Offsetting of Financial Liabi_3

Offsetting of Financial Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
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

Employee Stock Ownership Plan -

Employee Stock Ownership Plan - Loan, Expense and Shares (Details) - USD ($)		3 Months Ended
	Jan. 01, 2009	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Employee Stock Ownership Plan
Allocated shares		632,172		619,938
Unearned shares		232,431		244,665
Total ESOP shares		864,603		864,603
Fair value of unearned shares, in thousands		$ 1,873,000		$ 2,728,000
ESOP
Employee Stock Ownership Plan
Amount borrowed from employer	$ 9,800,000
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		$ 118,000	$ 281,000
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 ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
ESOP restoration | Certain executives
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits
Accrued (reversed) benefits	$ 11,000	$ (7,000)

Share-Based Compensation - Plan

Share-Based Compensation - Plan Provisions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023	Sep. 30, 2022
Share-Based Compensation
Compensation expense	$ 81	$ (42)	$ 81	$ (42)
Income tax benefit	$ 22	$ (11)
2010 Equity Incentive Plan | Vesting period one
Share-Based Compensation
Vesting period	3 years
2019 Equity Incentive Plan
Share-Based Compensation
Shares remaining available for new awards under the 2019 Equity Plan	42,680

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Awards (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
2019 Equity Incentive Plan
Unrecognized compensation
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	42,680
Restricted Stock
Restricted Stock Awards
Unvested at beginning of period (in shares)	25,738	23,664
Granted (in shares)	0	0
Vested (in shares)		4,540
Unvested at end of period (in shares)	25,738	19,124
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)	$ 21.61	$ 24.15
Granted (in dollars per share)	0	0
Vested (in dollars per share)		21.05
Unvested at end of period (in dollars per share)	$ 21.61	$ 24.89
Unrecognized compensation
Unrecognized compensation costs	$ 288,000
Restricted Stock Units Based on a Performance Condition
Restricted Stock Awards
Unvested at beginning of period (in shares)	44,967	43,557
Forfeited (in shares)	12,797	16,348
Unvested at end of period (in shares)	32,170	27,209
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)	$ 22.85	$ 23.63
Forfeited (in dollars per share)	26.77	21.05
Unvested at end of period (in dollars per share)	$ 21.30	$ 25.18
Unrecognized compensation
Unrecognized compensation costs, period of recognition	3 years
Restricted Stock Units Based on a Market Condition
Restricted Stock Awards
Unvested at beginning of period (in shares)	11,245	10,889
Forfeited (in shares)	3,199	4,087
Unvested at end of period (in shares)	8,046	6,802
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)	$ 22.31	$ 24.04
Forfeited (in dollars per share)	26	22.16
Unvested at end of period (in dollars per share)	$ 20.85	$ 25.16
Unrecognized compensation
Unrecognized compensation costs	$ 50,000
Unrecognized compensation costs, period of recognition	3 years
Performance Based Restricted Stock Units (PRSUs)
Unrecognized compensation
Unrecognized compensation costs	$ 457,000
Unrecognized compensation costs, period of recognition	3 years

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share
Net (loss) income	$ (482)	$ 2,316
Income allotted to participating securities	(1)	(19)
Net (loss) income available to common shareholders	$ (483)	$ 2,297
Weighted-average number of shares used in:
Basic earnings per share (in shares)	8,588,137	8,774,634
Dilutive common stock equivalents:
Stock options and restricted stock units (in shares)	42,582	32,110
Diluted earnings per share (in shares)	8,630,719	8,806,744
Net income per common share, basic (in dollars per share)	$ (0.06)	$ 0.26
Net income per common share, diluted (in dollars per share)	$ (0.06)	$ 0.26

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss - Changes in Components of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	$ (251,086)	$ (256,550)
Other comprehensive (income) loss, net of taxes	396	(337)
Net current period other comprehensive (income) loss	396	(337)
Balances at end of period	(250,016)	(253,761)
Accumulated Other Comprehensive (Loss)/Income
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	6,221	7,744
Net current period other comprehensive (income) loss	396	(337)
Balances at end of period	6,617	7,407
Unfunded Pension Liability
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	4,466	5,746
Balances at end of period	4,466	5,746
Unrealized (Gain) / Loss on Securities
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	1,755	1,998
Other comprehensive (income) loss, net of taxes	396	(337)
Net current period other comprehensive (income) loss	396	(337)
Balances at end of period	2,151	1,661
Other comprehensive (income) loss, net of taxes
Changes in the components of accumulated other comprehensive loss, net of taxes
Other comprehensive (income) loss, net of taxes	$ 396	$ (337)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Loss - Tax Effect on Each Component (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Tax effect on each component of other comprehensive loss
Pretax amount	$ 540	$ (459)
Tax	(144)	122
After Tax Amount	396	(337)
Unrealized (Gain) / Loss on Securities
Tax effect on each component of other comprehensive loss
Pretax amount	540	(459)
Tax	(144)	122
After Tax Amount	$ 396	$ (337)

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenues
Revenue from contracts with customers	$ 280	$ 317
Other revenue	67	68
Total	347	385
Service and Other Fees
Revenues
Revenue from contracts with customers	240	275
Other revenue	33	35
Total	273	310
Other
Revenues
Revenue from contracts with customers	40	42
Other revenue	34	33
Total	$ 74	$ 75

Leases - Lease Costs (Details)

Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Lease costs:
Operating lease costs	$ 666	$ 705
Short-term lease costs	163	104
Variable lease costs	43	43
Total lease costs	872	852
Cash paid for amounts included in measurement of lease liabilities		769
Cash paid for amounts included in measurement of lease liabilities	(195)
ROU assets obtained in exchange for new operating lease liabilities	$ 404	$ 118

Leases - Future Minimum Rental

Leases - Future Minimum Rental Commitments Under Non-cancellable Leases (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Future minimum rental commitments:
2023	$ 2,625
2024	2,228
2025	2,086
2026	2,001
2027	1,709
Thereafter	8,910
Total	19,559
Less present value discount	(1,962)
Present value of leases	$ 17,597	$ 17,297

Leases - Other Related Informat

Leases - Other Related Information (Details)	Mar. 31, 2024	Mar. 31, 2023
Leases
Weighted-average remaining lease term (years)	9 years 9 months 3 days	8 years 9 months 18 days
Weighted-average discount rate	2.14%	2.09%

Fair Value - Estimated Fair Val

Fair Value - Estimated Fair Values (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Assets
Investment securities available for sale, at fair value	$ 19,483	$ 20,171
Investment securities held to maturity	547,290		$ 547,290	$ 568,128
Liabilities
Advances from Federal Reserve Bank	50,000	50,000
Carrying Amount
Assets
Cash and cash equivalents	90,059	126,659
Investment securities available for sale, at fair value	19,483	20,171
Investment securities held to maturity	677,578	685,728
Loans receivable, net	1,309,712	1,303,431
FHLB stock	12,232	12,192
FRB stock	3,182	3,180
Accrued interest receivable	6,281	6,105
Liabilities
Deposits	1,600,148	1,636,604
Advances from the Federal Home Loan Bank	242,000	242,000
Advances from Federal Reserve Bank	50,000	50,000
Securities sold under agreements to repurchase	10,000	10,000
Accrued interest payable	1,285	1,183
Estimated Fair Value
Assets
Cash and cash equivalents	90,059	126,659
Investment securities available for sale, at fair value	19,483	20,171
Investment securities held to maturity	547,290	568,128
Loans receivable, net	1,095,737	1,120,704
FHLB stock	12,232	12,192
FRB stock	3,182	3,180
Accrued interest receivable	6,281	6,105
Liabilities
Deposits	1,596,514	1,633,164
Advances from the Federal Home Loan Bank	238,033	238,380
Advances from Federal Reserve Bank	49,815	50,049
Securities sold under agreements to repurchase	9,755	9,700
Accrued interest payable	1,285	1,183
Estimated Fair Value | Level 1
Assets
Cash and cash equivalents	90,059	126,659
Accrued interest receivable	158	79
Estimated Fair Value | Level 2
Assets
Investment securities available for sale, at fair value	19,483	20,171
Investment securities held to maturity	547,290	568,128
FHLB stock	12,232	12,192
FRB stock	3,182	3,180
Accrued interest receivable	1,472	1,441
Liabilities
Deposits	1,072,875	1,104,171
Advances from the Federal Home Loan Bank	238,033	238,380
Advances from Federal Reserve Bank	49,815	50,049
Securities sold under agreements to repurchase	9,755	9,700
Accrued interest payable	537	157
Estimated Fair Value | Level 3
Assets
Loans receivable, net	1,095,737	1,120,704
Accrued interest receivable	4,651	4,585
Liabilities
Deposits	523,639	528,993
Accrued interest payable	$ 748	$ 1,026

Fair Value - Recurring Basis (D

Fair Value - Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Assets and Liabilities Measured at Fair Value on Recurring Basis
Investment securities available for sale, at fair value	$ 19,483	$ 20,171
Fair Value, Measurements, Recurring
Assets and Liabilities Measured at Fair Value on Recurring Basis
Investment securities available for sale, at fair value	19,483	20,171
Fair Value, Measurements, Recurring | Level 2
Assets and Liabilities Measured at Fair Value on Recurring Basis
Investment securities available for sale, at fair value	$ 19,483	$ 20,171

Fair Value - Nonrecurring Basis

Fair Value - Nonrecurring Basis (Details) $ in Thousands	Mar. 31, 2024 USD ($)
Fair Value, Measurements, Nonrecurring
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Fair value	$ 0

Subsequent Events (Details)

Subsequent Events (Details) $ / shares in Units, $ in Millions		3 Months Ended
	Apr. 26, 2024 USD ($)	Mar. 31, 2024 $ / shares	Mar. 31, 2023 $ / shares
Subsequent Events
Quarterly cash dividend declared on common stock (in dollars per share) | $ / shares		$ 0.05	$ 0.23
Conversion of Stock [Line Items]
Fixed exchange ratio	0.8048
Stock for stock transaction percent	100%
Value of stock-for-stock transaction | $	$ 78.6

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023	Dec. 31, 2023
Recently Issued Accounting Pronouncements [Abstract]
Provision (reversal of provision) for credit losses	$ 19	$ (100)	$ 19
After-tax decrease to retained earnings	$ 210,771			$ 211,644

Investment Securities - Availab

Investment Securities - Available-for-Sale Unrealized Loss Position Summary (Details) $ in Thousands	Mar. 31, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Investment Securities
12 Months or Longer Fair Value	$ 19,483	$ 20,171
12 Months or Longer Unrealized Losses	$ (2,932)	$ (2,392)
Number of Securities | security	4	4
Total Fair Value	$ 19,483	$ 20,171
Total Unrealized Losses	$ (2,932)	$ (2,392)

Investment Securities - Avail_2

Investment Securities - Available-for-Sale Unrealized Loss and Held-to-Maturity Total Unrealized Loss Position Summary (Details) $ in Thousands	Mar. 31, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Investment Securities
Total Less Than 12 Months Unrealized Fair Value		$ 10,326
Total Less Than 12 Months Unrealized Losses		(107)
Total 12 Months or Longer Unrealized Fair Value	$ 563,571	574,685
Total 12 Months or Longer Unrealized Losses	$ (133,256)	$ (119,953)
Total Number of Securities | security	156	156
Total Fair value	$ 563,571	$ 585,011
Total Unrealized losses	$ (133,256)	$ (120,060)