Territorial Bancorp (TBNK) 10-Q 9 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 31, 2020
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2020
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	1132 Bishop Street, Suite 2200
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	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		9,513,867
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001447051
Amendment Flag	false

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 237,498	$ 44,806
Investment securities available for sale, at fair value	3,959	8,628
Investment securities held to maturity, at amortized cost (fair value of $309,471 and $371,305 at September 30, 2020 and December 31, 2019, respectively)	292,528	363,883
Loans held for sale	834	470
Loans receivable, net	1,482,639	1,584,784
Federal Home Loan Bank stock, at cost	8,144	8,723
Federal Reserve Bank stock, at cost	3,145	3,128
Accrued interest receivable	7,214	5,409
Premises and equipment, net	4,937	4,370
Right-of-use asset, net	13,375	11,580
Bank-owned life insurance	45,720	45,113
Deferred income tax assets, net	3,290	2,619
Prepaid expenses and other assets	3,034	2,800
Total assets	2,106,317	2,086,313
Liabilities:
Deposits	1,662,706	1,631,933
Advances from the Federal Home Loan Bank	141,000	156,000
Securities sold under agreements to repurchase	10,000	10,000
Accounts payable and accrued expenses	25,304	23,038
Lease liability	14,130	12,183
Income taxes payable	2,411	2,305
Advance payments by borrowers for taxes and insurance	4,108	6,964
Total liabilities	1,859,659	1,842,423
Stockholders' Equity:
Preferred stock, $0.01 par value; authorized 50,000,000 shares, no shares issued or outstanding
Common stock, $0.01 par value; authorized 100,000,000 shares; issued and outstanding 9,513,867 and 9,681,493 shares at September 30, 2020 and December 31, 2019, respectively	95	97
Additional paid-in capital	60,905	65,057
Unearned ESOP shares	(4,037)	(4,404)
Retained earnings	197,562	190,808
Accumulated other comprehensive loss	(7,867)	(7,668)
Total stockholders' equity	246,658	243,890
Total liabilities and stockholders' equity	$ 2,106,317	$ 2,086,313

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Consolidated Balance Sheets (Unaudited)
Investment securities held to maturity, fair value (in dollars)	$ 309,471	$ 371,305
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized shares	50,000,000	50,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares	100,000,000	100,000,000
Common stock, shares issued	9,513,867	9,681,493
Common stock, shares outstanding	9,513,867	9,681,493

Consolidated Statements of Inco

Consolidated Statements of Income (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest income:
Loans	$ 14,628,000	$ 15,864,000	$ 45,310,000	$ 47,475,000
Investment securities	2,264,000	2,865,000	7,654,000	8,583,000
Other investments	239,000	219,000	753,000	709,000
Total interest income	17,131,000	18,948,000	53,717,000	56,767,000
Interest expense:
Deposits	1,897,000	3,382,000	7,385,000	10,120,000
Advances from the Federal Home Loan Bank	724,000	973,000	2,448,000	2,425,000
Securities sold under agreements to repurchase	46,000	42,000	137,000	173,000
Total interest expense	2,667,000	4,397,000	9,970,000	12,718,000
Net interest income	14,464,000	14,551,000	43,747,000	44,049,000
Provision for loan losses	692,000	111,000	2,304,000	65,000
Net interest income after provision for loan losses	13,772,000	14,440,000	41,443,000	43,984,000
Noninterest income:
Revenue from contracts with customers	310,000	384,000	1,006,000	1,184,000
Income on bank-owned life insurance	204,000	215,000	607,000	632,000
Gain on sale of investment securities	261,000	123,000	858,000	2,910,000
Gain on sale of loans	321,000	1,205,000	987,000	1,211,000
Total noninterest income	1,577,000	2,102,000	4,339,000	6,815,000
Noninterest expense:
Salaries and employee benefits	5,346,000	5,586,000	16,294,000	17,002,000
Occupancy	1,701,000	1,610,000	4,972,000	4,780,000
Equipment	1,155,000	1,039,000	3,439,000	3,150,000
Federal deposit insurance premiums	138,000	1,000	212,000	288,000
Other general and administrative expenses	1,046,000	1,165,000	2,978,000	3,466,000
Total noninterest expense	9,386,000	9,401,000	27,895,000	28,686,000
Income before income taxes	5,963,000	7,141,000	17,887,000	22,113,000
Income taxes	1,645,000	1,775,000	4,805,000	5,163,000
Net income	$ 4,318,000	$ 5,366,000	$ 13,082,000	$ 16,950,000
Basic earnings per share (in dollars per share)	$ 0.47	$ 0.58	$ 1.43	$ 1.83
Diluted earnings per share (in dollars per share)	0.47	0.57	1.42	1.81
Cash dividends declared (in dollars per share)	$ 0.23	$ 0.22	$ 0.69	$ 0.76
Basic weighted-average shares outstanding (in shares)	9,104,079	9,212,119	9,144,463	9,184,741
Diluted weighted-average shares outstanding (in shares)	9,134,089	9,295,729	9,201,882	9,309,420
Service Fees on Loan and Deposit Accounts
Noninterest income:
Revenue from contracts with customers	$ 275,000	$ 347,000	$ 918,000	$ 1,047,000
Service fees on loan and deposit accounts	728,000	504,000	1,716,000	1,427,000
Other
Noninterest income:
Revenue from contracts with customers	35,000	37,000	88,000	137,000
Other	$ 63,000	$ 55,000	$ 171,000	$ 635,000

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Consolidated Statements of Comprehensive Income (Unaudited)
Net income	$ 4,318	$ 5,366	$ 13,082	$ 16,950
Change in unrealized (loss) gain on securities, net of tax	(4)	(21)	(199)	588
Other comprehensive (loss) gain, net of tax	(4)	(21)	(199)	588
Comprehensive income	$ 4,314	$ 5,345	$ 12,883	$ 17,538

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Unearned ESOP Shares	Retained Earnings	Accumulated Other Comprehensive Loss	Total
Balance at Dec. 31, 2018	$ 97	$ 65,090	$ (4,893)	$ 182,594	$ (7,809)	$ 235,079
Balance (in shares) at Dec. 31, 2018	9,645,955
Increase (Decrease) in Stockholders' Equity
Net income				16,950		16,950
Other comprehensive income (loss)					588	588
Adoption of lease accounting standard				(10)		(10)
Cash dividends declared				(7,014)		(7,014)
Share-based compensation		494				494
Share-based compensation (in shares)	6,541
Allocation of ESOP shares		661	367			1,028
Repurchase of shares of common stock	$ (2)	(5,042)				(5,044)
Repurchase of shares of common stock (in shares)	(180,944)
Exercise of options for common stock	$ 2	3,529				3,531
Exercise of options for common stock (in shares)	203,370
Balance at Sep. 30, 2019	$ 97	64,732	(4,526)	192,520	(7,221)	245,602
Balance (in shares) at Sep. 30, 2019	9,674,922
Balance at Jun. 30, 2019	$ 97	64,335	(4,649)	189,189	(7,200)	241,772
Balance (in shares) at Jun. 30, 2019	9,664,793
Increase (Decrease) in Stockholders' Equity
Net income				5,366		5,366
Other comprehensive income (loss)					(21)	(21)
Cash dividends declared				(2,035)		(2,035)
Share-based compensation		123				123
Allocation of ESOP shares		227	123			350
Repurchase of shares of common stock		(321)				(321)
Repurchase of shares of common stock (in shares)	(11,071)
Exercise of options for common stock		368				368
Exercise of options for common stock (in shares)	21,200
Balance at Sep. 30, 2019	$ 97	64,732	(4,526)	192,520	(7,221)	245,602
Balance (in shares) at Sep. 30, 2019	9,674,922
Balance at Dec. 31, 2019	$ 97	65,057	(4,404)	190,808	(7,668)	243,890
Balance (in shares) at Dec. 31, 2019	9,681,493
Increase (Decrease) in Stockholders' Equity
Net income				13,082		13,082
Other comprehensive income (loss)					(199)	(199)
Cash dividends declared				(6,328)		(6,328)
Share-based compensation		523				523
Share-based compensation (in shares)	18,875
Allocation of ESOP shares		538	367			905
Repurchase of shares of common stock	$ (3)	(6,633)				(6,636)
Repurchase of shares of common stock (in shares)	(268,328)
Exercise of options for common stock	$ 1	1,420				1,421
Exercise of options for common stock (in shares)	81,827
Balance at Sep. 30, 2020	$ 95	60,905	(4,037)	197,562	(7,867)	246,658
Balance (in shares) at Sep. 30, 2020	9,513,867
Balance at Jun. 30, 2020	$ 95	60,606	(4,159)	195,348	(7,863)	244,027
Balance (in shares) at Jun. 30, 2020	9,513,867
Increase (Decrease) in Stockholders' Equity
Net income				4,318		4,318
Other comprehensive income (loss)					(4)	(4)
Cash dividends declared				(2,104)		(2,104)
Share-based compensation		157				157
Allocation of ESOP shares		142	122			264
Balance at Sep. 30, 2020	$ 95	$ 60,905	$ (4,037)	$ 197,562	$ (7,867)	$ 246,658
Balance (in shares) at Sep. 30, 2020	9,513,867

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Consolidated Statements of Stockholders' Equity, Share Data
Cash dividends declared (in dollars per share)	$ 0.23	$ 0.22	$ 0.69	$ 0.76
Common Stock
Consolidated Statements of Stockholders' Equity, Share Data
Allocation of ESOP shares, shares	12,233	12,233	36,699	36,699

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income	$ 13,082,000	$ 16,950,000
Adjustments to reconcile net income to net cash from operating activities:
Provision for loan losses	2,304,000	65,000
Depreciation and amortization	899,000	876,000
Deferred income tax (benefit) expense	(599,000)	874,000
Amortization of fees, discounts, and premiums, net	(228,000)	(419,000)
Amortization of right-of-use asset	2,238,000	2,076,000
Origination of loans held for sale	(22,605,000)	(3,845,000)
Proceeds from sales of loans held for sale	22,822,000	3,631,000
Gain on sale of loans, net	(987,000)	(1,211,000)
Gain on sale of investment securities available for sale	(290,000)	(153,000)
Gain on sale of investment securities held to maturity	(568,000)	(2,757,000)
Net gain on disposal of premises and equipment	(4,000)
ESOP expense	905,000	1,028,000
Share-based compensation expense	523,000	494,000
Increase in accrued interest receivable	(1,805,000)	(220,000)
Net increase in bank-owned life insurance	(607,000)	(631,000)
Net (increase) decrease in prepaid expenses and other assets	(96,000)	54,000
Net increase in accounts payable and accrued expenses	2,080,000	245,000
Net decrease in lease liability	(2,146,000)	(2,000,000)
Net decrease in advance payments by borrowers for taxes and insurance	(2,856,000)	(3,087,000)
Net increase (decrease) in income taxes payable	106,000	(232,000)
Net cash from operating activities	12,168,000	11,738,000
Cash flows from investing activities:
Purchases of investment securities held to maturity		(7,845,000)
Principal repayments on investment securities held to maturity	71,118,000	28,043,000
Principal repayments on investment securities available for sale	1,013,000	917,000
Proceeds from sale of investment securities held to maturity	10,429,000	3,527,000
Proceeds from sale of investment securities available for sale	3,668,000	5,117,000
Principal repayments on loans receivable, net of loan originations	90,780,000	(47,118,000)
Purchases of Federal Home Loan Bank stock	(21,000)	(21,642,000)
Proceeds from redemption of Federal Home Loan Bank stock	600,000	19,896,000
Purchases of Federal Reserve Bank stock	(17,000)	(14,000)
Proceeds from bank-owned life insurance		788,000
Purchases of premises and equipment	(1,466,000)	(383,000)
Proceeds from disposals of premises and equipment	4,000
Net cash from investing activities	176,108,000	(18,714,000)
Cash flows from financing activities:
Net increase (decrease) in deposits	30,773,000	(23,970,000)
Proceeds from advances from the Federal Home Loan Bank		539,100,000
Repayments of advances from the Federal Home Loan Bank	(15,000,000)	(497,400,000)
Proceeds from securities sold under agreements to repurchase	5,000,000
Repayments of securities sold under agreements to repurchase	(5,000,000)	(20,000,000)
Purchases of Fed Funds	10,000	10,000
Sales of Fed Funds	(10,000)	(10,000)
Proceeds from issuance of common stock		170,000
Repurchases of common stock	(5,000,000)	(1,597,000)
Cash dividends paid	(6,357,000)	(6,980,000)
Net cash from financing activities	4,416,000	(10,677,000)
Net increase (decrease) in cash and cash equivalents	192,692,000	(17,653,000)
Cash and cash equivalents at beginning of the period	44,806,000	47,063,000
Cash and cash equivalents at end of the period	237,498,000	29,410,000
Cash paid for:
Interest on deposits and borrowings	10,268,000	12,772,000
Income taxes	6,208,000	4,521,000
Supplemental disclosure of noncash investing and financing activities:
Company stock acquired through stock swap and net settlement transactions	1,421,000	3,361,000
Company stock repurchased through stock swap and net settlement transactions	1,636,000	3,447,000
Loans securitized into investment securities	9,431,000	30,145,000
Loans receivable transferred to held for sale		29,229,000
Dividends declared, not yet paid	29,000	(34,000)
Establishment of right-of-use asset, net of incentives	4,033,000	13,254,000
Establishment of lease liability	$ 4,093,000	13,733,000
Transfer of securities from held-to-maturity to available-for-sale		$ 11,390,000

Organization

Organization	9 Months Ended
	Sep. 30, 2020
Organization
Organization	(1) Organization ​ In 2009, Territorial Savings Bank (the Bank) completed a conversion from a mutual holding company to a stock holding company and Territorial Bancorp Inc. (the Company) became the holding company for Territorial Savings Bank. Upon completion of the conversion and reorganization, a special “liquidation account” was established in an amount equal to the total equity of Territorial Mutual Holding Company as of December 31, 2008. The liquidation account is to provide eligible account holders and supplemental eligible account holders who maintain their deposit accounts with Territorial Savings Bank after the conversion with a liquidation interest in the unlikely event of the complete liquidation of Territorial Savings Bank after the conversion. ​ In 2014, Territorial Savings Bank converted from a federal savings bank to a Hawaii state-chartered savings bank and became a member of the Federal Reserve System.

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2020
Basis of Presentation
Basis of Presentation	(2) Basis of Presentation ​ The accompanying unaudited 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, 2019. 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.

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	9 Months Ended
	Sep. 30, 2020
Recently Issued Accounting Pronouncements
Recently Issued Accounting Pronouncements	(3) Recently Issued Accounting Pronouncements ​ In June 2016, the Financial Accounting Standards Board (FASB) amended various sections of the FASB Accounting Standards Codification (ASC) related to the accounting for credit losses on financial instruments. The amendment changes the threshold for recognizing losses from a “probable” to an “expected” model. The new model is referred to as the current expected credit loss model and applies to loans, leases, held-to-maturity investments, loan commitments and financial guarantees. The amendment requires the measurement of all expected credit losses for financial assets as of the reporting date (including historical experience, current conditions and reasonable and supportable forecasts) and enhanced disclosures that will help financial statement users understand the estimates and judgments used in estimating credit losses and evaluating the credit quality of an organization’s portfolio. The amendment is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. In November 2019, the FASB issued an update that delays the effective date of the amendment for smaller reporting companies, as defined by the Securities and Exchange Commission, to fiscal years beginning after December 15, 2022. The Company is a smaller reporting company. The Company will apply the amendment’s provisions as a cumulative-effect adjustment to retained earnings at the beginning of the first period the amendment is effective. The Company has formed a team that is working on an implementation plan to adopt the amendment. The implementation plan will include developing policies, procedures and internal controls over the model. The Company is also working with a software vendor to measure expected losses required by the amendment. The Company is currently evaluating the effects that the adoption of this amendment will have on its consolidated financial statements and expects that the portfolio composition and economic conditions at the time of adoption will influence the accounting adjustment made at the time the amendment is adopted. ​ In August 2018, the FASB amended the Fair Value Measurement topic of the FASB ASC. The amendment affects disclosures only, and includes additions, deletions and modifications of the disclosures of assets and liabilities reported in the fair value hierarchy. The amendment is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Early adoption is permitted. Entities are allowed to early adopt any removed or modified disclosures while delaying adoption of any added disclosures until the effective date. The Company adopted this amendment as of January 1, 2020 and it did not have a material effect on its consolidated financial statements. ​ In August 2018, the FASB amended the Compensation – Retirement Benefits topic of the FASB ASC. The amendment affects disclosures related to defined benefit pension or other post retirement plans and includes additions, deletions and clarifications of disclosures. The amendment is effective for fiscal years ending after December 15, 2020, with early adoption permitted. The Company does not expect the adoption of this amendment to have a material effect on its consolidated financial statements. ​ See Note (6), “Loans Receivable and Allowance for Loan Losses” in our Notes to Consolidated Financial Statements for a change in the treatment of troubled debt restructuring in the CARES Act. ​

Cash and Cash Equivalents

Cash and Cash Equivalents	9 Months Ended
	Sep. 30, 2020
Cash and Cash Equivalents
Cash and Cash Equivalents	(4) Cash and Cash Equivalents ​ The table below presents the balances of cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, (Dollars in thousands) 2020 2019 Cash and due from banks ​ $ 10,873 ​ $ 9,571 ​ Interest-earning deposits in other banks ​ 226,625 ​ 35,235 ​ Cash and cash equivalents ​ $ 237,498 ​ $ 44,806 ​ ​ Interest-earning deposits in other banks consist primarily of deposits at the Federal Reserve Bank of San Francisco.

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2020
Investment Securities.
Investment Securities	(5) Investment Securities ​ The amortized cost and fair values of investment securities are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross Unrealized ​ Estimated (Dollars in thousands) Cost Gains Losses Fair Value September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 3,534 ​ $ 425 $ — ​ $ 3,959 ​ Total ​ $ 3,534 ​ $ 425 $ — ​ $ 3,959 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 292,528 ​ $ 16,945 $ (2) ​ $ 309,471 ​ Total ​ $ 292,528 ​ $ 16,945 $ (2) ​ $ 309,471 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 7,905 ​ $ 723 $ — ​ $ 8,628 ​ Total ​ $ 7,905 ​ $ 723 $ — ​ $ 8,628 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 363,883 ​ $ 8,436 $ (1,014) ​ $ 371,305 ​ Total ​ $ 363,883 ​ $ 8,436 $ (1,014) ​ $ 371,305 ​ ​ The amortized cost and estimated fair value of investment securities by maturity date at September 30, 2020 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 within 5 years ​ $ — ​ $ — ​ Due after 5 years through 10 years ​ — ​ — ​ Due after 10 years ​ 3,534 ​ 3,959 ​ Total ​ $ 3,534 ​ $ 3,959 ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ Due within 5 years ​ $ — ​ $ — ​ Due after 5 years through 10 years ​ 62 ​ 61 ​ Due after 10 years ​ 292,466 ​ 309,410 ​ Total ​ $ 292,528 ​ $ 309,471 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Realized gains and losses and the proceeds from sales of held-to-maturity and available-for-sale securities are shown in the table below. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ September 30, ​ September 30, ​ (Dollars in thousands) 2020 2019 2020 2019 Proceeds from sales ​ $ 5,737 ​ $ 4,308 ​ $ 14,097 ​ $ 8,644 ​ Gross gains ​ 261 ​ 123 ​ 858 ​ 2,910 ​ Gross losses ​ — ​ — ​ — ​ — ​ ​ During the nine months ended September 30, 2020, the Company sold $9.9 million of held-to-maturity mortgage-backed securities and recorded a gain of $568,000 . During the nine months ended September 30, 2019, the Company sold its . The sale of the trust preferred security, which had a significant deterioration in the issuer’s credit rating, and the sale of the mortgage-backed securities, for which the Company had already collected a substantial portion of the outstanding purchased principal (at least ​ During the nine months ended September 30, 2020, the Company sold $3.4 million of available-for-sale mortgage-backed securities and recorded a gain of $290,000 . During the nine months ended September 30, 2019, the Company sold ​ As of January 1, 2019, the Company transferred securities with an amortized cost of $11.4 million from held-to-maturity to available-for-sale with the adoption of ASU 2017-12 on derivatives and hedging. ​ Investment securities with amortized costs of $217.5 million and $188.9 million at September 30, 2020 and December 31, 2019, respectively, were pledged to secure deposits made by state and local governments, securities sold under agreements to repurchase and transaction clearing accounts. ​ Provided below is a summary of investment securities that were in an unrealized loss position at September 30, 2020 and December 31, 2019. The Company does not intend to sell held-to-maturity and available-for-sale 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) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 958 ​ $ (1) ​ $ 4 ​ $ (1) 6 ​ $ 962 ​ $ (2) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 55,882 ​ $ (302) ​ $ 34,492 ​ $ (712) 30 ​ $ 90,374 ​ $ (1,014) ​ ​ Mortgage-Backed Securities. The unrealized losses on the Company’s investment in mortgage-backed securities were caused by increases in market interest rates subsequent to purchase. All of the mortgage-backed securities are guaranteed by Freddie Mac or Fannie Mae, which are U.S. government-sponsored enterprises, or Ginnie Mae, which is a U.S. government agency. Since the decline in market value is attributable to changes in interest rates and not credit quality, and the Company does not intend to sell these investments until maturity and it is not more likely than not that the Company will be required to sell such investments prior to recovery of its cost basis, the Company does not consider these investments to be other-than-temporarily impaired as of September 30, 2020 and December 31, 2019. ​ During the nine months ended September 30, 2020, the Company securitized fixed-rate first mortgage loans with a book value of $9.4 million into Freddie Mac mortgage-backed securities to increase liquidity. The securitization transaction increased investment securities and lowered loans receivable. The securitization transaction was accounted for by recording the mortgage-backed securities at a fair value of million in accordance with the Transfers and Servicing topic of the FASB ASC. Mortgage servicing assets of

Loans Receivable and Allowance

Loans Receivable and Allowance for Loan Losses	9 Months Ended
	Sep. 30, 2020
Loans Receivable and Allowance for Loan Losses
Loans Receivable and Allowance for Loan Losses	(6) Loans Receivable and Allowance for Loan Losses ​ The components of loans receivable are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ (Dollars in thousands) 2020 2019 Real estate loans: ​ ​ ​ ​ ​ ​ ​ First mortgages: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential ​ $ 1,436,900 ​ $ 1,536,781 ​ Multi-family residential ​ 8,897 ​ 9,965 ​ Construction, commercial and other ​ 22,250 ​ 23,382 ​ Home equity loans and lines of credit ​ 9,704 ​ 10,084 ​ Total real estate loans ​ 1,477,751 ​ 1,580,212 ​ Other loans: ​ ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ 272 ​ 235 ​ Consumer and other loans ​ 11,475 ​ 9,484 ​ Total other loans ​ 11,747 ​ 9,719 ​ Less: ​ ​ ​ ​ ​ ​ ​ Net unearned fees and discounts ​ (1,917) ​ (2,435) ​ Allowance for loan losses ​ (4,942) ​ (2,712) ​ Total unearned fees, discounts and allowance for loan losses ​ (6,859) ​ (5,147) ​ Loans receivable, net ​ $ 1,482,639 ​ $ 1,584,784 ​ ​ The table below presents the activity in the allowance for loan losses by portfolio segment: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals Three months ended September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 3,020 ​ $ 459 ​ $ 1 ​ $ 197 ​ $ 579 ​ $ 4,256 ​ Provision (reversal of provision) for loan losses ​ 988 ​ (2) ​ — ​ (21) ​ (273) ​ 692 ​ ​ ​ 4,008 ​ 457 ​ 1 ​ 176 ​ 306 ​ 4,948 ​ Charge-offs ​ — ​ — ​ — ​ (6) ​ — ​ (6) ​ Recoveries ​ — ​ — ​ — ​ — ​ — ​ — ​ Net charge-offs ​ — ​ — ​ — ​ (6) ​ — ​ (6) ​ Balance, end of period ​ $ 4,008 ​ $ 457 ​ $ 1 ​ $ 170 ​ $ 306 ​ $ 4,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,741 ​ $ 511 ​ $ 1 ​ $ 54 ​ $ 405 ​ $ 2,712 ​ Provision (reversal of provision) for loan losses ​ 2,267 ​ (54) ​ (10) ​ 200 ​ (99) ​ 2,304 ​ ​ ​ 4,008 ​ 457 ​ (9) ​ 254 ​ 306 ​ 5,016 ​ Charge-offs ​ — ​ — ​ — ​ (86) ​ — ​ (86) ​ Recoveries ​ — ​ — ​ 10 ​ 2 ​ — ​ 12 ​ Net recoveries (charge-offs) ​ — ​ — ​ 10 ​ (84) ​ — ​ (74) ​ Balance, end of period ​ $ 4,008 ​ $ 457 ​ $ 1 ​ $ 170 ​ $ 306 ​ $ 4,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals Three months ended September 30, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,769 ​ $ 411 ​ $ 1 ​ $ 44 ​ $ 391 ​ $ 2,616 ​ (Reversal of provision) provision for loan losses ​ (11) ​ 90 ​ — ​ 15 ​ 17 ​ 111 ​ ​ ​ 1,758 ​ 501 ​ 1 ​ 59 ​ 408 ​ 2,727 ​ Charge-offs ​ — ​ — ​ — ​ (5) ​ — ​ (5) ​ Recoveries ​ — ​ — ​ — ​ 2 ​ — ​ 2 ​ Net charge-offs ​ — ​ — ​ — ​ (3) ​ — ​ (3) ​ Balance, end of period ​ $ 1,758 ​ $ 501 ​ $ 1 ​ $ 56 ​ $ 408 ​ $ 2,724 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,797 ​ $ 443 ​ $ 1 ​ $ 47 ​ $ 354 ​ $ 2,642 ​ (Reversal of provision) provision for loan losses ​ (57) ​ 58 ​ — ​ 10 ​ 54 ​ 65 ​ ​ ​ 1,740 ​ 501 ​ 1 ​ 57 ​ 408 ​ 2,707 ​ Charge-offs ​ — ​ — ​ — ​ (21) ​ — ​ (21) ​ Recoveries ​ 18 ​ — ​ — ​ 20 ​ — ​ 38 ​ Net recoveries (charge-offs) ​ 18 ​ — ​ — ​ (1) ​ — ​ 17 ​ Balance, end of period ​ $ 1,758 ​ $ 501 ​ $ 1 ​ $ 56 ​ $ 408 ​ $ 2,724 ​ ​ Management considers the allowance for loan losses at September 30, 2020 to be at an appropriate level to provide for probable losses that can be reasonably estimated based on general and specific conditions at that date. While the Company uses the best information it has available to make evaluations, future adjustments to the allowance may be necessary if conditions differ substantially from the information used in making the evaluations. To the extent actual outcomes differ from the estimates, additional provisions for credit losses may be required that would reduce future earnings. In addition, as an integral part of their examination process, the bank regulators periodically review the allowance for loan losses and may require the Company to increase the allowance based on their analysis of information available at the time of their examination. The loan loss provision for the nine months ended September 30, 2020 was $2.3 million compared to $65,000 for the nine months ended September 30, 2019. The increase in the loan loss provision occurred primarily from an increase in the qualitative factors used to calculate the allowance for loan losses. The qualitative factors increased because Hawaii’s unemployment rate increased due to layoffs that resulted from government mandates to minimize the spread of COVID-19. ​ The table below presents the balance in the allowance for loan losses and the recorded investment in loans by portfolio segment and based on impairment method: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 4,008 ​ 457 ​ 1 ​ 170 ​ 306 ​ 4,942 ​ Total ending allowance balance ​ $ 4,008 ​ $ 457 ​ $ 1 ​ $ 170 ​ $ 306 ​ $ 4,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 2,732 ​ $ — ​ $ 23 ​ $ — ​ $ — ​ $ 2,755 ​ Collectively evaluated for impairment ​ 1,441,193 ​ 22,191 ​ 9,682 ​ 11,760 ​ — ​ 1,484,826 ​ Total ending loan balance ​ $ 1,443,925 ​ $ 22,191 ​ $ 9,705 ​ $ 11,760 ​ $ — ​ $ 1,487,581 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 1,741 ​ 511 ​ 1 ​ 54 ​ 405 ​ 2,712 ​ Total ending allowance balance ​ $ 1,741 ​ $ 511 ​ $ 1 ​ $ 54 ​ $ 405 ​ $ 2,712 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 1,224 ​ $ — ​ $ 89 ​ $ — ​ $ — ​ $ 1,313 ​ Collectively evaluated for impairment ​ 1,543,125 ​ 23,326 ​ 9,997 ​ 9,735 ​ — ​ 1,586,183 ​ Total ending loan balance ​ $ 1,544,349 ​ $ 23,326 ​ $ 10,086 ​ $ 9,735 ​ $ — ​ $ 1,587,496 ​ ​ The table below presents the balance of impaired loans individually evaluated for impairment by class of loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid Recorded Principal (Dollars in thousands) Investment Balance September 30, 2020: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,732 ​ $ 3,164 ​ Home equity loans and lines of credit ​ 23 ​ 32 ​ Total ​ $ 2,755 ​ $ 3,196 ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,224 ​ $ 1,615 ​ Home equity loans and lines of credit ​ ​ 89 ​ ​ 178 ​ Total ​ $ 1,313 ​ $ 1,793 ​ ​ The table below presents the average recorded investment and interest income recognized on impaired loans by class of loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months Ended For the Nine Months Ended September 30, September 30, Average Interest Average Interest Recorded Income Recorded Income (Dollars in thousands) Investment Recognized Investment Recognized 2020: ​ ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,745 ​ $ 8 ​ $ 2,770 ​ $ 25 ​ Home equity loans and lines of credit ​ 24 ​ — ​ 25 ​ — ​ Total ​ $ 2,769 ​ $ 8 ​ $ 2,795 ​ $ 25 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,364 ​ $ 8 ​ $ 1,391 ​ $ 25 ​ Home equity loans and lines of credit ​ ​ 96 ​ — ​ 100 ​ — ​ Total ​ $ 1,460 ​ $ 8 ​ $ 1,491 ​ $ 25 ​ ​ ​ There were no loans individually evaluated for impairment with a related allowance for loan loss as of September 30, 2020 or December 31, 2019. Loans individually evaluated for impairment do not have an allocated allowance for loan loss because they are written down to fair value at the time of impairment. ​ The Company had eight nonaccrual loans with a book value of $2.2 million as of September 30, 2020 and six nonaccrual loans with a book value of $736,000 as of December 31, 2019. The Company collected interest on nonaccrual loans of during the nine months ended September 30, 2020 and 2019, respectively, but due to accounting and regulatory requirements, the Company recorded the interest as a reduction of principal. The Company would have recognized additional interest income of during the nine months ended September 30, 2020 and 2019, respectively, had the loans been accruing interest. The Company did not have any 90 days or more past due and still accruing interest as of September 30, 2020. At December 31, 2019, the Company had ​ The table below presents the aging of loans and accrual status by class of loans, net of unearned fees and discounts: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 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 September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ 140 ​ $ 122 ​ $ 262 ​ $ 1,434,781 ​ $ 1,435,043 ​ $ 2,163 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 8,882 ​ 8,882 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 22,191 ​ 22,191 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ 23 ​ — ​ 23 ​ 9,682 ​ 9,705 ​ 23 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 272 ​ 272 ​ — ​ — ​ Consumer and other ​ 6 ​ — ​ — ​ 6 ​ 11,482 ​ 11,488 ​ — ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 6 ​ $ 163 ​ $ 122 ​ $ 291 ​ $ 1,487,290 ​ $ 1,487,581 ​ $ 2,186 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ 959 ​ $ — ​ $ 959 ​ $ 1,533,446 ​ $ 1,534,405 ​ $ 647 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 9,944 ​ 9,944 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 23,326 ​ 23,326 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ 26 ​ — ​ 26 ​ 10,060 ​ 10,086 ​ 89 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 235 ​ 235 ​ — ​ — ​ Consumer and other ​ 33 ​ 1 ​ 1 ​ 35 ​ 9,465 ​ 9,500 ​ — ​ 1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 33 ​ $ 986 ​ $ 1 ​ $ 1,020 ​ $ 1,586,476 ​ $ 1,587,496 ​ $ 736 ​ $ 1 ​ ​ ​ The Company primarily uses the aging of loans and accrual status to monitor the credit quality of its loan portfolio. When a mortgage loan becomes seriously delinquent ( 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. ​ There were no loans modified in a troubled debt restructuring during the nine months ended September 30, 2020 or 2019. There were new troubled debt restructurings within the 12 months ended September 30, 2020 or 2019 that subsequently defaulted. ​ The table below summarizes troubled debt restructurings by class of loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of Accrual Number of Nonaccrual ​ (Dollars in thousands) Loans Status Loans Status Total September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 3 ​ $ 568 ​ ​ 2 ​ $ 481 ​ $ 1,049 Total ​ 3 ​ $ 568 ​ ​ 2 ​ $ 481 ​ $ 1,049 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 3 ​ $ 577 ​ ​ 2 ​ $ 525 ​ $ 1,102 Home equity loans and lines of credit ​ — ​ — ​ 1 ​ 64 ​ 64 Total ​ 3 ​ $ 577 ​ ​ 3 ​ $ 589 ​ $ 1,166 ​ There were no delinquent troubled debt restructurings as of September 30, 2020 or December 31, 2019. Restructurings include deferrals of interest and/or principal payments and temporary or permanent reductions in interest rates due to the financial difficulties of the borrowers. At September 30, 2020, we had ​ The Coronavirus Aid, Relief, and Economic Security (CARES) Act was passed by Congress and signed into law by the President on March 27, 2020. The CARES Act provides relief to financial institutions from categorizing eligible loan modifications as troubled debt restructurings over the remaining life of the modified loan. In addition, Interagency Statements were issued on March 22, 2020 and April 7, 2020 by bank regulatory agencies to encourage financial institutions to work prudently with borrowers who may be unable to meet their contractual payment obligations because of the effects of COVID-19. ​ The Company has granted loan deferrals to borrowers who have been affected by COVID-19. As of September 30, 2020, the Company granted loan deferrals on $146.2 million of loans, which represent 9.9% of total loans receivable. $140.9 million of these loan deferrals consist of one- to four-family residential mortgage loans, which represent 9.5% of the total loans receivable. The Company believes these loans are currently well secured as the ratio of the current loan balance to the current tax-assessed value of the property securing these mortgage loans averages 54.9%. One- to four-family residential mortgage loans represent 96.9% of the Company’s total loan portfolio balance. All of our residential mortgage loans are secured by real estate in Hawaii. The Company believes that the total one- to four-family residential mortgage loans are also well-secured as the ratio of the current loan balance to the current tax-assessed value of the property securing these loans averages 45.5%. The Company has also granted loan deferrals of $5.3 million on other non-residential mortgage loans, which represent 0.4% of the total balance of loans receivable. The loans on which the Company has granted loan deferrals are included in the ALLL calculation. Loans performing under a loan deferral agreement are not contractually past due and are excluded from the past due statistics above. ​ The Company had no real estate owned as of September 30, 2020 or December 31, 2019. 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 nine months ended September 30, 2020 and 2019, the Company sold mortgage loans held for sale with principal balances of $22.3 million and $3.6 million, respectively, and recognized gains of $610,000 and $18,000 , respectively. The Company had ​ During the nine months ended September 30, 2020, the Company securitized fixed-rate first mortgage loans with a book value of $9.4 million and received mortgage-backed securities with a fair market value of $9.8 million. The Company retained the servicing of these loans and recorded mortgage servicing assets with a fair market value of ​ The Company serviced loans for others with principal balances of $62.7 million at September 30, 2020 and $65.1 million at December 31, 2019. Of these amounts, million of loan balances relate to securitizations for which the Company continues to hold the related mortgage-backed securities at September 30, 2020 and December 31, 2019, respectively. The amount of contractually specified servicing fees earned for the nine months ended September 30, 2020 and 2019 was , respectively. The amount of contractually specified servicing fees earned for the three months ended September 30, 2020 and 2019 was , respectively. The fees are reported in service fees on loan and deposit accounts in the consolidated statements of income.

Securities Sold Under Agreement

Securities Sold Under Agreements to Repurchase	9 Months Ended
	Sep. 30, 2020
Securities Sold Under Agreements to Repurchase
Securities Sold Under Agreements to Repurchase	(7) 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 ​ Weighted Weighted ​ Repurchase Average Repurchase Average ​ (Dollars in thousands) Liability Rate Liability Rate ​ Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 1 year or less ​ $ — — % $ 5,000 1.65 % ​ Over 4 year to 5 years ​ 10,000 1.81 ​ 5,000 1.88 ​ ​ Total ​ $ 10,000 1.81 % $ 10,000 1.77 % ​ ​ 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 September 30, 2020. 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-sponsored enterprises. The repurchase liability cannot exceed of the fair value of securities pledged. In the event of a decline in the fair value of securities pledged to less than the required amount due to market conditions or principal repayments, the Company is obligated to pledge additional securities or other suitable collateral to cure the deficiency. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted Carrying Fair Average Value of Value of Repurchase Amount Months to (Dollars in thousands) Securities Securities Liability at Risk Maturity Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Over 90 days ​ $ 10,001 ​ $ 10,994 ​ $ 10,000 ​ $ 994 51 ​ ​

Offsetting of Financial Liabili

Offsetting of Financial Liabilities	9 Months Ended
	Sep. 30, 2020
Offsetting of Financial Liabilities
Offsetting of Financial Liabilities	(8) Offsetting of Financial Liabilities ​ The following table presents our securities sold under agreements to repurchase that are subject to a right of offset in the event of default. See Note 7, 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 September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2020
Employee Benefit Plans
Employee Benefit Plans	(9) Employee Benefit Plans ​ The Company has a noncontributory defined benefit pension plan (Pension Plan) that covers most employees with at least one year of service. Effective December 31, 2008, under approved changes to the Pension Plan, there were no further accruals of benefits for any participants and benefits will not increase with any additional years of service. Net periodic benefit cost, subsequent to December 31, 2008, has not been significant and is not disclosed in the table below. ​ The Company also sponsors a Supplemental Employee Retirement Plan (SERP), a noncontributory supplemental retirement benefit plan, which covers certain current and former employees of the Company for amounts in addition to those provided under the Pension Plan. ​ The components of net periodic benefit cost were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ SERP SERP Three Months Ended Nine Months Ended September 30, September 30, (Dollars in thousands) 2020 2019 2020 2019 Net periodic benefit cost for the period: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service cost ​ $ 22 ​ $ 26 ​ $ 66 ​ $ 77 ​ Interest cost ​ 43 ​ 41 ​ 130 ​ 122 ​ Expected return on plan assets ​ — ​ — ​ — ​ — ​ Amortization of prior service cost ​ — ​ — ​ — ​ — ​ Recognized actuarial loss ​ — ​ — ​ — ​ — ​ Recognized curtailment loss ​ — ​ — ​ — ​ — ​ Net periodic benefit cost ​ $ 65 ​ $ 67 ​ $ 196 ​ $ 199 ​ ​ The service cost component of net periodic benefit cost is included with salaries and employee benefits in the consolidated statements of income. The other components of net periodic benefit cost are included in other general and administrative expenses.

Employee Stock Ownership Plan

Employee Stock Ownership Plan	9 Months Ended
	Sep. 30, 2020
Employee Stock Ownership Plan
Employee Stock Ownership Plan
Employee Stock Ownership Plan	(10) 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 September 30, 2020 and 2019 amounted to , respectively. Compensation expense recognized for the nine months ended September 30, 2020 and 2019 amounted to ​ Shares held by the ESOP trust were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, 2020 2019 Allocated shares ​ 495,070 ​ 466,807 ​ Unearned shares ​ 403,698 ​ 440,397 ​ Total ESOP shares ​ 898,768 ​ 907,204 ​ Fair value of unearned shares, in thousands ​ $ 8,167 ​ $ 13,626 ​ ​ 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 September 30, 2020 and 2019, we accrued , respectively, for the ESOP restoration plan. For the nine months ended September 30, 2020 and 2019, we accrued

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2020
2010 Equity Incentive Plan
Share-Based Compensation
Share-Based Compensation	(11) Share-Based Compensation ​ On August 19, 2010, Territorial Bancorp Inc. adopted the 2010 Equity Incentive Plan, which provides for awards of stock options and restricted stock to key officers and outside directors. In accordance with the Compensation – Stock Compensation topic of the FASB ASC, the cost of the 2010 Equity Incentive Plan is based on the fair value of the awards on the grant date. The fair value of restricted stock is based on the closing price of the Company’s stock on the grant date. The fair value of stock options is estimated using a Black-Scholes option pricing model using assumptions for dividend yield, stock price volatility, risk-free interest rate and option term. These assumptions are based on our judgments regarding future events, are subjective in nature, and cannot be determined with precision. The cost of the awards will be recognized on a straight-line basis over the three , five - or six-year vesting period during which participants are required to provide services in exchange for the awards. ​ 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 statement of income as a component of salaries and employee benefits with a corresponding increase in stockholders’ equity. The table below presents information on compensation expense and the related tax benefit for all share-based awards: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2020 2019 2020 2019 Compensation expense ​ $ 157 ​ $ 123 ​ $ 523 ​ $ 494 ​ Income tax benefit ​ 43 ​ 33 ​ 143 ​ 135 ​ ​ Shares of our common stock issued under the 2010 Equity Incentive Plan shall come from authorized shares. The maximum number of shares that will be awarded under the plan will be ​ Stock Options ​ The table below presents the stock option activity for the nine months ended September 30, 2020 and 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Aggregate ​ ​ ​ ​ Average ​ Remaining ​ Intrinsic ​ ​ ​ ​ Exercise ​ Contractual ​ Value ​ ​ Options ​ Price ​ Life (years) ​ (in thousands) Options outstanding at December 31, 2019 116,409 ​ $ 17.53 0.72 ​ $ 1,562 ​ Granted — ​ — — ​ — ​ Exercised 81,827 ​ 17.36 — ​ 725 ​ Forfeited — ​ — — ​ — ​ Expired 31,497 ​ — — ​ — ​ Options outstanding at September 30, 2020 ​ 3,085 ​ $ 23.62 1.92 ​ $ (11) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options outstanding at December 31, 2018 337,654 ​ $ 17.51 1.74 ​ $ 2,859 ​ Granted — ​ — — ​ — ​ Exercised 203,370 ​ 17.36 — ​ 2,282 ​ Forfeited — ​ — — ​ — ​ Expired — ​ — — ​ — ​ Options outstanding at September 30, 2019 134,284 ​ $ 17.74 1.10 ​ $ 1,455 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options vested and exercisable at September 30, 2020 3,085 ​ $ 23.62 1.92 ​ $ (11) ​ ​ The following summarizes certain stock option activity of the Company: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months Ended For the Nine Months Ended September 30, September 30, (In thousands) 2020 2019 2020 2019 Intrinsic value of stock options exercised ​ $ — ​ $ 251 ​ $ 725 ​ $ 2,282 ​ Proceeds received from stock options exercised ​ — ​ 368 ​ 1,421 ​ 3,531 ​ Tax benefits realized from stock options exercised ​ — ​ 60 ​ 158 ​ 484 ​ Total fair value of stock options that vested ​ — ​ — ​ — ​ — ​ ​ During the nine months ended September 30, 2020, we issued 27,194 shares of common stock, net, in exchange for 81,827 stock options and 54,633 shares of common stock. Pursuant to the provisions of our equity incentive plan, optionees are permitted to use the value of our common stock they own in a net settlement to pay the exercise price of stock options. ​ As of September 30, 2020, the Company had no unrecognized compensation costs related to the stock option plan. ​ 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 restricted stock activity: ​ ​ ​ ​ ​ ​ ​ ​ Weighted Average Grant Restricted Date Fair Stock Value Unvested at December 31, 2019 20,249 ​ $ 28.78 ​ Granted 13,444 ​ 21.05 ​ Vested 9,998 ​ 29.16 ​ Forfeited — ​ — ​ Unvested at September 30, 2020 23,695 ​ $ 24.24 ​ ​ ​ ​ ​ ​ ​ ​ Unvested at December 31, 2018 16,424 ​ $ 30.26 ​ Granted 10,366 ​ 27.30 ​ Vested 6,541 ​ 30.14 ​ Forfeited — ​ — ​ Unvested at September 30, 2019 20,249 ​ $ 28.78 ​ ​ During the nine months ended September 30, 2020, the Company issued 13,444 shares of restricted stock to certain members of executive management under the 2019 Equity Incentive Plan. The fair value of the restricted stock is based on the value of the Company’s stock on the date of grant. Restricted stock will vest over three years from the date of grant. ​ As of September 30, 2020, the Company had $410,000 of unrecognized compensation costs related to restricted stock. ​ During the nine months ended September 30, 2020, the Company issued 16,129 performance-based restricted stock units (PRSUs) to certain members of executive management under the 2019 Equity Incentive Plan. These PRSUs will vest in the first quarter of 2023 after our Compensation Committee determines whether a performance condition that compares the Company’s return on average equity to the SNL Bank Index is achieved. Depending on the Company’s performance, the actual number of these PRSUs that are issued at the end of the vesting period can vary between of the target award. For the PRSUs, an estimate is made of the number of shares expected to vest based on the probability that the performance criteria will be achieved to determine the amount of compensation expense to be recognized. This estimate is re-evaluated quarterly and total compensation expense is adjusted for any change in the current period. ​ The 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, 2019 35,976 ​ $ 29.16 Granted 16,129 ​ 21.05 Vested 7,680 ​ 29.53 Forfeited 3,840 ​ 29.53 Unvested at September 30, 2020 40,585 ​ $ 25.83 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2018 23,538 ​ $ 30.14 Granted 12,438 ​ 27.30 Vested — ​ — Forfeited — ​ — Unvested at September 30, 2019 35,976 ​ $ 29.16 ​ The fair value of these PRSUs is based on the fair value of the Company’s stock on the date of grant. As of September 30, 2020, the Company had $428,000 of unrecognized compensation costs related to these PRSUs. Performance will be measured over a three-year performance period and will be cliff vested. ​ During the nine months ended September 30, 2020, the Company issued 4,032 of PRSUs to certain members of executive management under the 2019 Equity Incentive Plan. These PRSUs will vest in the first quarter of 2023 after our Compensation Committee determines whether a market condition that compares the Company’s total stock return to the SNL Bank Index is achieved. The number of shares that will be expensed will not be adjusted for performance. The fair value of these PRSUs is based on a Monte Carlo valuation of the Company’s stock on the date of grant. The assumptions which were used in the Monte Carlo valuation of the PRSUs are: ​ Grant date: March 12, 2020 Performance period: January 1, 2020 to December 31, 2022 2.80 year risk-free rate on grant date: 0.56% December 31, 2019 closing price: $30.94 Closing stock price on the date of grant: $21.05 Annualized volatility (based on 2.82 year historical volatility as of the grant date): 18.02% ​ 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, 2019 8,994 ​ $ 25.74 Granted 4,032 ​ 22.16 Vested 1,197 ​ 24.44 Forfeited 1,682 ​ 24.44 Unvested at September 30, 2020 10,147 ​ $ 24.69 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2018 5,884 ​ $ 26.42 Granted 3,110 ​ 24.45 Vested — ​ — Forfeited — ​ — Unvested at September 30, 2019 8,994 ​ $ 25.74 ​ As of September 30, 2020, the Company had $90,000 of unrecognized compensation costs related to the PRSUs that are based on a market condition. Performance will be measured over a three-year performance period and will be cliff vested.

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2020
Earnings Per Share
Earnings Per Share	(12) 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 Nine Months Ended September 30, September 30, (Dollars in thousands, except per share data) 2020 2019 2020 2019 Net income ​ $ 4,318 ​ $ 5,366 ​ $ 13,082 ​ $ 16,950 ​ Income allocated to participating securities ​ ​ (23) ​ ​ (38) ​ ​ (47) ​ ​ (112) ​ Net income available to common shareholders ​ $ 4,295 ​ $ 5,328 ​ $ 13,035 ​ $ 16,838 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average number of shares used in: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share ​ 9,104,079 ​ 9,212,119 ​ 9,144,463 ​ 9,184,741 ​ Dilutive common stock equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ 30,010 ​ 83,610 ​ 57,419 ​ 124,679 ​ Diluted earnings per share ​ 9,134,089 ​ 9,295,729 ​ 9,201,882 ​ 9,309,420 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income per common share, basic ​ $ 0.47 ​ $ 0.58 ​ $ 1.43 ​ $ 1.83 ​ Net income per common share, diluted ​ $ 0.47 ​ $ 0.57 ​ $ 1.42 ​ $ 1.81 ​ ​

Other Comprehensive Income and

Other Comprehensive Income and Loss	9 Months Ended
	Sep. 30, 2020
Other Comprehensive Income and Loss
Other Comprehensive Income and Loss	(13) Other Comprehensive Income and Loss ​ The table below presents the changes in the components of accumulated other comprehensive income and loss, net of taxes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unfunded Unrealized Pension (Gain)/Loss on (Dollars in thousands) Liability Securities Total Three months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 8,178 ​ $ (315) ​ $ 7,863 ​ Other comprehensive loss, net of taxes ​ ​ — ​ 4 ​ 4 ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ — ​ — ​ Net current period other comprehensive loss ​ — ​ 4 ​ 4 ​ Balances at end of period ​ $ 8,178 ​ $ (311) ​ $ 7,867 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 7,721 ​ $ (521) ​ $ 7,200 ​ Other comprehensive income, net of taxes ​ — ​ (70) ​ (70) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 91 ​ 91 ​ Net current period other comprehensive loss ​ — ​ 21 ​ 21 ​ Balances at end of period ​ $ 7,721 ​ $ (500) ​ $ 7,221 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 8,178 ​ $ (510) ​ $ 7,668 ​ Other comprehensive income, net of taxes ​ — ​ (22) ​ (22) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 221 ​ 221 ​ Net current period other comprehensive loss ​ — ​ 199 ​ 199 ​ Balances at end of period ​ $ 8,178 ​ $ (311) ​ $ 7,867 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 7,721 ​ $ 88 ​ $ 7,809 ​ Other comprehensive income, net of taxes ​ — ​ (711) ​ (711) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 123 ​ 123 ​ Net current period other comprehensive income ​ — ​ (588) ​ (588) ​ Balances at end of period ​ $ 7,721 ​ $ (500) ​ $ 7,221 ​ ​ The table below presents the tax effect on each component of accumulated other comprehensive income and loss: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, 2020 2019 Pretax After Tax Pretax After Tax (Dollars in thousands) Amount Tax Amount Amount Tax Amount Unrealized loss (gain) on securities ​ $ 5 ​ $ (1) ​ $ 4 ​ $ (95) ​ $ 25 ​ $ (70) ​ Amount reclassified from other comprehensive income ​ ​ — ​ ​ — ​ ​ — ​ ​ 123 ​ ​ (32) ​ ​ 91 ​ Total ​ $ 5 ​ $ (1) ​ $ 4 ​ $ 28 ​ $ (7) ​ $ 21 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended September 30, ​ 2020 2019 ​ Pretax After Tax Pretax After Tax (Dollars in thousands) Amount Tax Amount Amount Tax Amount Unrealized gain on securities ​ $ (30) ​ $ 8 ​ $ (22) ​ $ (969) ​ $ 258 ​ $ (711) ​ Amount reclassified from other comprehensive income ​ ​ 301 ​ ​ (80) ​ ​ 221 ​ ​ 167 ​ ​ (44) ​ ​ 123 ​ Total ​ $ 271 ​ $ (72) ​ $ 199 ​ $ (802) ​ $ 214 ​ $ (588) ​ ​

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2020
Revenue Recognition
Revenue Recognition	(14) 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 fees on loan and deposit accounts and in other noninterest income in the consolidated statements of income. The table below reconciles the revenue from contracts with customers and other revenue reported in those line items: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service Fees on ​ ​ ​ ​ Loan and Deposit ​ ​ ​ ​ (Dollars in thousands) Accounts Other Total Three months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 275 ​ $ 35 ​ $ 310 Other revenue ​ ​ 453 ​ ​ 28 ​ ​ 481 Total ​ $ 728 ​ $ 63 ​ $ 791 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 347 ​ $ 37 ​ $ 384 Other revenue ​ ​ 157 ​ ​ 18 ​ ​ 175 Total ​ $ 504 ​ $ 55 ​ $ 559 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 918 ​ $ 88 ​ $ 1,006 Other revenue ​ ​ 798 ​ ​ 83 ​ ​ 881 Total ​ $ 1,716 ​ $ 171 ​ $ 1,887 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 1,047 ​ $ 137 ​ $ 1,184 Other revenue ​ ​ 380 ​ ​ 498 ​ ​ 878 Total ​ $ 1,427 ​ $ 635 ​ $ 2,062 ​

Leases

Leases	9 Months Ended
	Sep. 30, 2020
Leases
Leases	​ (15) Leases ​ The Company leases most of its premises and some vehicles and equipment under operating leases expiring on various dates through 2030. The majority of lease agreements relate to real estate and generally provide that the Company pay taxes, insurance, maintenance and certain other operating expenses applicable to the leased premises. Variable lease components and nonlease components are not included in the Company’s computation of the right-of-use (ROU) asset or lease liability. The Company also does not include short-term leases in the computation of the ROU asset or lease liability. Short-term leases are leases with a term at commencement of 12 months or less. Short-term lease expense is recorded on a straight-line basis over the term of the lease. Lease agreements do not contain any residual value guarantees or restrictive covenants. ​ Certain leases have renewal options at the expiration of the lease terms. Generally, option periods are not included in the computation of the lease term, ROU asset or lease liability because the Company is not reasonably certain to exercise renewal options at the expiration of the lease terms. The Company has elected to use the package of practical expedients to: a) not reassess whether any expired or existing contracts are or contain leases, b) not reassess the lease classification for any expired or existing leases, and c) not reassess initial direct costs for any existing leases. The Company has also chosen the option to not restate comparative periods prior to the adoption of the new lease accounting standard. ​ Because the discount rates implicit in our leases are not known, discount rates have been estimated using the rates for fixed-rate, amortizing advances from the Federal Home Loan Bank (FHLB) for the approximate terms of the leases. FHLB advances are collateralized by a blanket pledge of the Bank’s assets that are not otherwise pledged. ​ The table below presents lease costs and other information for the periods indicated: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended ​ September 30, September 30, (Dollars in thousands) 2020 2019 2020 2019 Lease Costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 878 ​ $ 777 ​ $ 2,509 ​ $ 2,342 ​ Short-term lease costs ​ 5 ​ 21 ​ 17 ​ 37 ​ Variable lease costs ​ 38 ​ 40 ​ 115 ​ 93 ​ Total lease costs ​ $ 921 ​ $ 838 ​ $ 2,641 ​ $ 2,472 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ $ 808 ​ $ 721 ​ $ 2,414 ​ $ 2,266 ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 2,247 ​ $ 246 ​ $ 4,033 ​ $ 13,254 ​ ​ At September 30, 2020, future minimum rental commitments under noncancellable operating leases are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ 2020 ​ $ 820 ​ ​ ​ ​ ​ ​ 2021 ​ 2,974 ​ ​ ​ ​ ​ ​ 2022 ​ 2,690 ​ ​ ​ ​ ​ ​ 2023 ​ 2,339 ​ ​ ​ ​ ​ ​ 2024 ​ 2,060 ​ ​ ​ ​ ​ ​ Thereafter ​ 4,294 ​ ​ ​ ​ ​ ​ Total ​ ​ 15,177 ​ ​ ​ ​ ​ ​ Less present value discount ​ ​ 1,047 ​ ​ ​ ​ ​ ​ Present value of leases ​ $ 14,130 ​ ​ ​ ​ ​ ​ ​ The table below presents other lease related information: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ ​ September 30, ​ ​ ​ 2020 ​ 2019 ​ Weighted-average remaining lease term (years) ​ 6.00 ​ ​ 6.23 ​ ​ Weighted-average discount rate ​ ​ 2.45 % ​ ​ 2.90 % ​ ​

Fair Value

Fair Value	9 Months Ended
	Sep. 30, 2020
Fair Value
Fair Value	(16) Fair Value ​ In accordance with the Fair Value Measurements and Disclosures topic of the FASB ASC, the Company groups its assets and liabilities measured or disclosed at fair value into three levels based on the markets in which the 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 held 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 assets at fair value on a nonrecurring basis, such as loans held for sale, impaired loans and investments, and mortgage servicing assets. These nonrecurring fair value adjustments typically involve application of the lower of cost or fair value accounting or write-downs of individual assets. ​ Investment Securities Available for Sale. ​ Interest Rate Contracts. The Company may enter into interest rate lock commitments with borrowers on loans intended to be sold. To manage interest rate risk on the lock commitments, the Company may also enter into forward loan sale commitments. The interest rate lock commitments and forward loan sale commitments are treated as derivatives and are recorded at their fair value determined by referring to prices quoted in the secondary market for similar contracts. The fair value inputs are considered Level 2 inputs. Interest rate contracts that are classified as assets are included with prepaid expenses and other assets on the consolidated balance sheet while interest rate contracts that are classified as liabilities are included with accounts payable and accrued expenses. ​ The estimated fair values of the Company’s financial instruments are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Carrying ​ ​ ​ ​ Fair Value Measurements Using (Dollars in thousands) Amount Fair Value Level 1 Level 2 Level 3 September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 237,498 ​ $ 237,498 ​ $ 237,498 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 3,959 ​ ​ 3,959 ​ ​ — ​ ​ 3,959 ​ ​ — ​ Investment securities held to maturity ​ 292,528 ​ ​ 309,471 ​ ​ — ​ ​ 309,471 ​ ​ — ​ Loans held for sale ​ 834 ​ ​ 870 ​ ​ — ​ ​ 870 ​ ​ — ​ Loans receivable, net ​ 1,482,639 ​ ​ 1,562,422 ​ ​ — ​ ​ — ​ ​ 1,562,422 ​ FHLB stock ​ 8,144 ​ ​ 8,144 ​ ​ — ​ ​ 8,144 ​ ​ — ​ FRB stock ​ ​ 3,145 ​ ​ 3,145 ​ ​ — ​ ​ 3,145 ​ ​ — ​ Accrued interest receivable ​ 7,214 ​ ​ 7,214 ​ ​ 19 ​ ​ 794 ​ ​ 6,401 ​ Interest rate contracts ​ 60 ​ ​ 60 ​ ​ — ​ ​ 60 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,662,706 ​ ​ 1,667,045 ​ ​ — ​ ​ 1,285,438 ​ ​ 381,607 ​ Advances from the Federal Home Loan Bank ​ 141,000 ​ ​ 145,623 ​ ​ — ​ ​ 145,623 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 10,484 ​ ​ — ​ ​ 10,484 ​ ​ — ​ Accrued interest payable ​ 99 ​ ​ 99 ​ ​ — ​ ​ 48 ​ ​ 51 ​ Interest rate contracts ​ 60 ​ ​ 60 ​ ​ — ​ ​ 60 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 44,806 ​ $ 44,806 ​ $ 44,806 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 8,628 ​ ​ 8,628 ​ ​ — ​ ​ 8,628 ​ ​ — ​ Investment securities held to maturity ​ 363,883 ​ ​ 371,305 ​ ​ — ​ ​ 371,305 ​ ​ — ​ Loans held for sale ​ 470 ​ ​ 480 ​ ​ — ​ ​ 480 ​ ​ — ​ Loans receivable, net ​ 1,584,784 ​ ​ 1,627,903 ​ ​ — ​ ​ — ​ ​ 1,627,903 ​ FHLB stock ​ 8,723 ​ ​ 8,723 ​ ​ — ​ ​ 8,723 ​ ​ — ​ FRB stock ​ ​ 3,128 ​ ​ 3,128 ​ ​ — ​ ​ 3,128 ​ ​ — ​ Accrued interest receivable ​ 5,409 ​ ​ 5,409 ​ ​ 32 ​ ​ 952 ​ ​ 4,425 ​ Interest rate contracts ​ 5 ​ ​ 5 ​ ​ — ​ ​ 5 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,631,933 ​ ​ 1,632,741 ​ ​ — ​ ​ 1,167,990 ​ ​ 464,751 ​ Advances from the Federal Home Loan Bank ​ 156,000 ​ ​ 156,906 ​ ​ — ​ ​ 156,906 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,968 ​ ​ — ​ ​ 9,968 ​ ​ — ​ Accrued interest payable ​ 397 ​ ​ 397 ​ ​ — ​ ​ 47 ​ ​ 350 ​ Interest rate contracts ​ 5 ​ ​ 5 ​ ​ — ​ ​ 5 ​ ​ — ​ ​ At September 30, 2020 and December 31, 2019, 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 September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts — assets ​ $ — ​ $ 60 ​ $ — ​ $ 60 ​ Interest rate contracts — liabilities ​ — ​ (60) ​ — ​ (60) ​ Investment securities available for sale ​ ​ — ​ ​ 3,959 ​ ​ — ​ ​ 3,959 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts — assets ​ $ — ​ $ 5 ​ $ — ​ $ 5 ​ Interest rate contracts — liabilities ​ — ​ (5) ​ — ​ (5) ​ Investment securities available for sale ​ — ​ 8,628 ​ — ​ 8,628 ​ ​ The table below presents the balance of assets measured at fair value on a nonrecurring basis as of September 30, 2020 and December 31, 2019 and the related losses for the nine months ended September 30, 2020 and the year ended December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value ​ ​ (Dollars in thousands) Adjustment Date ​ Level 1 Level 2 Level 3 Total ​ Total Losses ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ 9/30/2020 ​ $ — ​ $ — ​ $ 452 ​ $ 452 ​ $ (53) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ 9/30/2019 ​ ​ — ​ ​ — ​ ​ 452 ​ ​ 452 ​ ​ (16) ​ ​ Mortgage servicing assets are valued using a discounted cash flow model. Assumptions used in the model include mortgage prepayment speeds, discount rates and cost of servicing. Losses on mortgage servicing assets are included in service fees on loan and deposit accounts in the consolidated statements of income. ​ The table below presents the significant unobservable inputs for Level 3 nonrecurring fair value measurements. The discount rates and prepayment speeds have been weighted by the relative notional amounts. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unobservable Range (Dollars in thousands) Fair Value Valuation Technique Input (Weighted Average) September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ $ 452 ​ Discounted cash flow ​ Discount rate ​ ​ 9.25% - 11.25% (10.25%) ​ ​ ​ ​ ​ ​ ​ ​ Prepayment speed (CPR) ​ 9.36 - 18.16 (13.54) ​ ​ ​ ​ ​ ​ ​ ​ Annual cost to service (per loan, in dollars) ​ $ 75 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ $ 452 Discounted cash flow Discount rate ​ ​ 9.25% - 11.25% (10.25%) ​ ​ ​ ​ ​ ​ ​ Prepayment speed (CPR) ​ 11.09 - 14.24 (12.58) ​ ​ ​ ​ ​ ​ ​ Annual cost to service (per loan, in dollars) ​ $ 75 ​ ​

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2020
Subsequent Events
Subsequent Events	(17) Subsequent Events ​ On October 29, 2020, the Board of Directors of Territorial Bancorp Inc. declared a quarterly cash dividend of $0.23 per share of common stock. The dividend is expected to be paid on November 25, 2020 to stockholders of record as of November 12, 2020.

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	9 Months Ended
	Sep. 30, 2020
Cash and Cash Equivalents
Schedule of balances of cash and cash equivalents	​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, (Dollars in thousands) 2020 2019 Cash and due from banks ​ $ 10,873 ​ $ 9,571 ​ Interest-earning deposits in other banks ​ 226,625 ​ 35,235 ​ Cash and cash equivalents ​ $ 237,498 ​ $ 44,806 ​

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2020
Investment Securities.
Schedule of amortized cost and fair values of investment securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortized ​ Gross Unrealized ​ Estimated (Dollars in thousands) Cost Gains Losses Fair Value September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 3,534 ​ $ 425 $ — ​ $ 3,959 ​ Total ​ $ 3,534 ​ $ 425 $ — ​ $ 3,959 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 292,528 ​ $ 16,945 $ (2) ​ $ 309,471 ​ Total ​ $ 292,528 ​ $ 16,945 $ (2) ​ $ 309,471 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 7,905 ​ $ 723 $ — ​ $ 8,628 ​ Total ​ $ 7,905 ​ $ 723 $ — ​ $ 8,628 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 363,883 ​ $ 8,436 $ (1,014) ​ $ 371,305 ​ Total ​ $ 363,883 ​ $ 8,436 $ (1,014) ​ $ 371,305 ​ ​
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 within 5 years ​ $ — ​ $ — ​ Due after 5 years through 10 years ​ — ​ — ​ Due after 10 years ​ 3,534 ​ 3,959 ​ Total ​ $ 3,534 ​ $ 3,959 ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ Due within 5 years ​ $ — ​ $ — ​ Due after 5 years through 10 years ​ 62 ​ 61 ​ Due after 10 years ​ 292,466 ​ 309,410 ​ Total ​ $ 292,528 ​ $ 309,471 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of realized gains and losses and proceeds from sales of securities held to maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ ​ ​ September 30, ​ September 30, ​ (Dollars in thousands) 2020 2019 2020 2019 Proceeds from sales ​ $ 5,737 ​ $ 4,308 ​ $ 14,097 ​ $ 8,644 ​ Gross gains ​ 261 ​ 123 ​ 858 ​ 2,910 ​ Gross losses ​ — ​ — ​ — ​ — ​
Summary of investment securities in an unrealized loss position	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Less Than 12 Months 12 Months or Longer Total Unrealized Unrealized Number of Unrealized Description of securities Fair Value Losses Fair Value Losses Securities Fair Value Losses (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 958 ​ $ (1) ​ $ 4 ​ $ (1) 6 ​ $ 962 ​ $ (2) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Held-to-maturity: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government-sponsored mortgage-backed securities ​ $ 55,882 ​ $ (302) ​ $ 34,492 ​ $ (712) 30 ​ $ 90,374 ​ $ (1,014) ​ ​

Loans Receivable and Allowanc_2

Loans Receivable and Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2020
Loans Receivable and Allowance for Loan Losses
Schedule of components of loans receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ (Dollars in thousands) 2020 2019 Real estate loans: ​ ​ ​ ​ ​ ​ ​ First mortgages: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential ​ $ 1,436,900 ​ $ 1,536,781 ​ Multi-family residential ​ 8,897 ​ 9,965 ​ Construction, commercial and other ​ 22,250 ​ 23,382 ​ Home equity loans and lines of credit ​ 9,704 ​ 10,084 ​ Total real estate loans ​ 1,477,751 ​ 1,580,212 ​ Other loans: ​ ​ ​ ​ ​ ​ ​ Loans on deposit accounts ​ 272 ​ 235 ​ Consumer and other loans ​ 11,475 ​ 9,484 ​ Total other loans ​ 11,747 ​ 9,719 ​ Less: ​ ​ ​ ​ ​ ​ ​ Net unearned fees and discounts ​ (1,917) ​ (2,435) ​ Allowance for loan losses ​ (4,942) ​ (2,712) ​ Total unearned fees, discounts and allowance for loan losses ​ (6,859) ​ (5,147) ​ Loans receivable, net ​ $ 1,482,639 ​ $ 1,584,784 ​
Schedule of activity in allowance for loan losses on loans receivable and by portfolio segment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals Three months ended September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 3,020 ​ $ 459 ​ $ 1 ​ $ 197 ​ $ 579 ​ $ 4,256 ​ Provision (reversal of provision) for loan losses ​ 988 ​ (2) ​ — ​ (21) ​ (273) ​ 692 ​ ​ ​ 4,008 ​ 457 ​ 1 ​ 176 ​ 306 ​ 4,948 ​ Charge-offs ​ — ​ — ​ — ​ (6) ​ — ​ (6) ​ Recoveries ​ — ​ — ​ — ​ — ​ — ​ — ​ Net charge-offs ​ — ​ — ​ — ​ (6) ​ — ​ (6) ​ Balance, end of period ​ $ 4,008 ​ $ 457 ​ $ 1 ​ $ 170 ​ $ 306 ​ $ 4,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,741 ​ $ 511 ​ $ 1 ​ $ 54 ​ $ 405 ​ $ 2,712 ​ Provision (reversal of provision) for loan losses ​ 2,267 ​ (54) ​ (10) ​ 200 ​ (99) ​ 2,304 ​ ​ ​ 4,008 ​ 457 ​ (9) ​ 254 ​ 306 ​ 5,016 ​ Charge-offs ​ — ​ — ​ — ​ (86) ​ — ​ (86) ​ Recoveries ​ — ​ — ​ 10 ​ 2 ​ — ​ 12 ​ Net recoveries (charge-offs) ​ — ​ — ​ 10 ​ (84) ​ — ​ (74) ​ Balance, end of period ​ $ 4,008 ​ $ 457 ​ $ 1 ​ $ 170 ​ $ 306 ​ $ 4,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals Three months ended September 30, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,769 ​ $ 411 ​ $ 1 ​ $ 44 ​ $ 391 ​ $ 2,616 ​ (Reversal of provision) provision for loan losses ​ (11) ​ 90 ​ — ​ 15 ​ 17 ​ 111 ​ ​ ​ 1,758 ​ 501 ​ 1 ​ 59 ​ 408 ​ 2,727 ​ Charge-offs ​ — ​ — ​ — ​ (5) ​ — ​ (5) ​ Recoveries ​ — ​ — ​ — ​ 2 ​ — ​ 2 ​ Net charge-offs ​ — ​ — ​ — ​ (3) ​ — ​ (3) ​ Balance, end of period ​ $ 1,758 ​ $ 501 ​ $ 1 ​ $ 56 ​ $ 408 ​ $ 2,724 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance, beginning of period ​ $ 1,797 ​ $ 443 ​ $ 1 ​ $ 47 ​ $ 354 ​ $ 2,642 ​ (Reversal of provision) provision for loan losses ​ (57) ​ 58 ​ — ​ 10 ​ 54 ​ 65 ​ ​ ​ 1,740 ​ 501 ​ 1 ​ 57 ​ 408 ​ 2,707 ​ Charge-offs ​ — ​ — ​ — ​ (21) ​ — ​ (21) ​ Recoveries ​ 18 ​ — ​ — ​ 20 ​ — ​ 38 ​ Net recoveries (charge-offs) ​ 18 ​ — ​ — ​ (1) ​ — ​ 17 ​ Balance, end of period ​ $ 1,758 ​ $ 501 ​ $ 1 ​ $ 56 ​ $ 408 ​ $ 2,724 ​
Schedule of balance in allowance for loan losses and the recorded investment in loans by portfolio segment and based on impairment method	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Construction, Home Commercial Equity and Other Loans and Residential Mortgage Lines of Consumer (Dollars in thousands) Mortgage Loans Credit and Other Unallocated Totals September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 4,008 ​ 457 ​ 1 ​ 170 ​ 306 ​ 4,942 ​ Total ending allowance balance ​ $ 4,008 ​ $ 457 ​ $ 1 ​ $ 170 ​ $ 306 ​ $ 4,942 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 2,732 ​ $ — ​ $ 23 ​ $ — ​ $ — ​ $ 2,755 ​ Collectively evaluated for impairment ​ 1,441,193 ​ 22,191 ​ 9,682 ​ 11,760 ​ — ​ 1,484,826 ​ Total ending loan balance ​ $ 1,443,925 ​ $ 22,191 ​ $ 9,705 ​ $ 11,760 ​ $ — ​ $ 1,487,581 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for loan losses: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending allowance balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ Collectively evaluated for impairment ​ 1,741 ​ 511 ​ 1 ​ 54 ​ 405 ​ 2,712 ​ Total ending allowance balance ​ $ 1,741 ​ $ 511 ​ $ 1 ​ $ 54 ​ $ 405 ​ $ 2,712 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loans: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Ending loan balance: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Individually evaluated for impairment ​ $ 1,224 ​ $ — ​ $ 89 ​ $ — ​ $ — ​ $ 1,313 ​ Collectively evaluated for impairment ​ 1,543,125 ​ 23,326 ​ 9,997 ​ 9,735 ​ — ​ 1,586,183 ​ Total ending loan balance ​ $ 1,544,349 ​ $ 23,326 ​ $ 10,086 ​ $ 9,735 ​ $ — ​ $ 1,587,496 ​ ​
Schedule of balance of impaired loans individually evaluated for impairment by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ Unpaid Recorded Principal (Dollars in thousands) Investment Balance September 30, 2020: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,732 ​ $ 3,164 ​ Home equity loans and lines of credit ​ 23 ​ 32 ​ Total ​ $ 2,755 ​ $ 3,196 ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,224 ​ $ 1,615 ​ Home equity loans and lines of credit ​ ​ 89 ​ ​ 178 ​ Total ​ $ 1,313 ​ $ 1,793 ​
Schedule of average recorded investment and interest income recognized on impaired loans by class of loans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months Ended For the Nine Months Ended September 30, September 30, Average Interest Average Interest Recorded Income Recorded Income (Dollars in thousands) Investment Recognized Investment Recognized 2020: ​ ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 2,745 ​ $ 8 ​ $ 2,770 ​ $ 25 ​ Home equity loans and lines of credit ​ 24 ​ — ​ 25 ​ — ​ Total ​ $ 2,769 ​ $ 8 ​ $ 2,795 ​ $ 25 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ With no related allowance recorded: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ 1,364 ​ $ 8 ​ $ 1,391 ​ $ 25 ​ Home equity loans and lines of credit ​ ​ 96 ​ — ​ 100 ​ — ​ Total ​ $ 1,460 ​ $ 8 ​ $ 1,491 ​ $ 25 ​
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 September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ 140 ​ $ 122 ​ $ 262 ​ $ 1,434,781 ​ $ 1,435,043 ​ $ 2,163 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 8,882 ​ 8,882 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 22,191 ​ 22,191 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ 23 ​ — ​ 23 ​ 9,682 ​ 9,705 ​ 23 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 272 ​ 272 ​ — ​ — ​ Consumer and other ​ 6 ​ — ​ — ​ 6 ​ 11,482 ​ 11,488 ​ — ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 6 ​ $ 163 ​ $ 122 ​ $ 291 ​ $ 1,487,290 ​ $ 1,487,581 ​ $ 2,186 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ $ — ​ $ 959 ​ $ — ​ $ 959 ​ $ 1,533,446 ​ $ 1,534,405 ​ $ 647 ​ $ — ​ Multi-family residential mortgages ​ — ​ — ​ — ​ — ​ 9,944 ​ 9,944 ​ — ​ — ​ Construction, commercial and other mortgages ​ — ​ — ​ — ​ — ​ 23,326 ​ 23,326 ​ — ​ — ​ Home equity loans and lines of credit ​ — ​ 26 ​ — ​ 26 ​ 10,060 ​ 10,086 ​ 89 ​ — ​ Loans on deposit accounts ​ — ​ — ​ — ​ — ​ 235 ​ 235 ​ — ​ — ​ Consumer and other ​ 33 ​ 1 ​ 1 ​ 35 ​ 9,465 ​ 9,500 ​ — ​ 1 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ $ 33 ​ $ 986 ​ $ 1 ​ $ 1,020 ​ $ 1,586,476 ​ $ 1,587,496 ​ $ 736 ​ $ 1 ​
Summary of troubled debt restructurings by class of loan	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number of Accrual Number of Nonaccrual ​ (Dollars in thousands) Loans Status Loans Status Total September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 3 ​ $ 568 ​ ​ 2 ​ $ 481 ​ $ 1,049 Total ​ 3 ​ $ 568 ​ ​ 2 ​ $ 481 ​ $ 1,049 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ One- to four-family residential mortgages ​ 3 ​ $ 577 ​ ​ 2 ​ $ 525 ​ $ 1,102 Home equity loans and lines of credit ​ — ​ — ​ 1 ​ 64 ​ 64 Total ​ 3 ​ $ 577 ​ ​ 3 ​ $ 589 ​ $ 1,166

Securities Sold Under Agreeme_2

Securities Sold Under Agreements to Repurchase (Tables)	9 Months Ended
	Sep. 30, 2020
Securities Sold Under Agreements to Repurchase
Summary of securities sold under agreements to repurchase	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 December 31, 2019 ​ Weighted Weighted ​ Repurchase Average Repurchase Average ​ (Dollars in thousands) Liability Rate Liability Rate ​ Maturing: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 1 year or less ​ $ — — % $ 5,000 1.65 % ​ Over 4 year to 5 years ​ 10,000 1.81 ​ 5,000 1.88 ​ ​ Total ​ $ 10,000 1.81 % $ 10,000 1.77 % ​
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 ​ $ 10,001 ​ $ 10,994 ​ $ 10,000 ​ $ 994 51 ​

Offsetting of Financial Liabi_2

Offsetting of Financial Liabilities (Tables)	9 Months Ended
	Sep. 30, 2020
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 September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Securities sold under agreements to repurchase ​ $ 10,000 ​ $ — ​ $ 10,000 ​ $ 10,000 ​ $ — ​ $ —

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2020
Employee Benefit Plans
Schedule of components of net periodic benefit cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ SERP SERP Three Months Ended Nine Months Ended September 30, September 30, (Dollars in thousands) 2020 2019 2020 2019 Net periodic benefit cost for the period: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service cost ​ $ 22 ​ $ 26 ​ $ 66 ​ $ 77 ​ Interest cost ​ 43 ​ 41 ​ 130 ​ 122 ​ Expected return on plan assets ​ — ​ — ​ — ​ — ​ Amortization of prior service cost ​ — ​ — ​ — ​ — ​ Recognized actuarial loss ​ — ​ — ​ — ​ — ​ Recognized curtailment loss ​ — ​ — ​ — ​ — ​ Net periodic benefit cost ​ $ 65 ​ $ 67 ​ $ 196 ​ $ 199 ​

Employee Stock Ownership Plan (

Employee Stock Ownership Plan (Tables)	9 Months Ended
	Sep. 30, 2020
Employee Stock Ownership Plan
Schedule of shares held by the ESOP trust	​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, 2020 2019 Allocated shares ​ 495,070 ​ 466,807 ​ Unearned shares ​ 403,698 ​ 440,397 ​ Total ESOP shares ​ 898,768 ​ 907,204 ​ Fair value of unearned shares, in thousands ​ $ 8,167 ​ $ 13,626 ​

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2020
Schedule of compensation expense and related tax benefit for all share-based awards	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended September 30, September 30, (In thousands) 2020 2019 2020 2019 Compensation expense ​ $ 157 ​ $ 123 ​ $ 523 ​ $ 494 ​ Income tax benefit ​ 43 ​ 33 ​ 143 ​ 135 ​
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Aggregate ​ ​ ​ ​ Average ​ Remaining ​ Intrinsic ​ ​ ​ ​ Exercise ​ Contractual ​ Value ​ ​ Options ​ Price ​ Life (years) ​ (in thousands) Options outstanding at December 31, 2019 116,409 ​ $ 17.53 0.72 ​ $ 1,562 ​ Granted — ​ — — ​ — ​ Exercised 81,827 ​ 17.36 — ​ 725 ​ Forfeited — ​ — — ​ — ​ Expired 31,497 ​ — — ​ — ​ Options outstanding at September 30, 2020 ​ 3,085 ​ $ 23.62 1.92 ​ $ (11) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options outstanding at December 31, 2018 337,654 ​ $ 17.51 1.74 ​ $ 2,859 ​ Granted — ​ — — ​ — ​ Exercised 203,370 ​ 17.36 — ​ 2,282 ​ Forfeited — ​ — — ​ — ​ Expired — ​ — — ​ — ​ Options outstanding at September 30, 2019 134,284 ​ $ 17.74 1.10 ​ $ 1,455 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options vested and exercisable at September 30, 2020 3,085 ​ $ 23.62 1.92 ​ $ (11) ​
Summary of certain stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Three Months Ended For the Nine Months Ended September 30, September 30, (In thousands) 2020 2019 2020 2019 Intrinsic value of stock options exercised ​ $ — ​ $ 251 ​ $ 725 ​ $ 2,282 ​ Proceeds received from stock options exercised ​ — ​ 368 ​ 1,421 ​ 3,531 ​ Tax benefits realized from stock options exercised ​ — ​ 60 ​ 158 ​ 484 ​ Total fair value of stock options that vested ​ — ​ — ​ — ​ — ​
Restricted Stock
Schedule of restricted stock award activity	​ ​ ​ ​ ​ ​ ​ ​ Weighted Average Grant Restricted Date Fair Stock Value Unvested at December 31, 2019 20,249 ​ $ 28.78 ​ Granted 13,444 ​ 21.05 ​ Vested 9,998 ​ 29.16 ​ Forfeited — ​ — ​ Unvested at September 30, 2020 23,695 ​ $ 24.24 ​ ​ ​ ​ ​ ​ ​ ​ Unvested at December 31, 2018 16,424 ​ $ 30.26 ​ Granted 10,366 ​ 27.30 ​ Vested 6,541 ​ 30.14 ​ Forfeited — ​ — ​ Unvested at September 30, 2019 20,249 ​ $ 28.78 ​
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, 2019 35,976 ​ $ 29.16 Granted 16,129 ​ 21.05 Vested 7,680 ​ 29.53 Forfeited 3,840 ​ 29.53 Unvested at September 30, 2020 40,585 ​ $ 25.83 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2018 23,538 ​ $ 30.14 Granted 12,438 ​ 27.30 Vested — ​ — Forfeited — ​ — Unvested at September 30, 2019 35,976 ​ $ 29.16
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, 2019 8,994 ​ $ 25.74 Granted 4,032 ​ 22.16 Vested 1,197 ​ 24.44 Forfeited 1,682 ​ 24.44 Unvested at September 30, 2020 10,147 ​ $ 24.69 ​ ​ ​ ​ ​ ​ Unvested at December 31, 2018 5,884 ​ $ 26.42 Granted 3,110 ​ 24.45 Vested — ​ — Forfeited — ​ — Unvested at September 30, 2019 8,994 ​ $ 25.74

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2020
Earnings Per Share
Schedule of information used to compute basic and diluted earnings per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended September 30, September 30, (Dollars in thousands, except per share data) 2020 2019 2020 2019 Net income ​ $ 4,318 ​ $ 5,366 ​ $ 13,082 ​ $ 16,950 ​ Income allocated to participating securities ​ ​ (23) ​ ​ (38) ​ ​ (47) ​ ​ (112) ​ Net income available to common shareholders ​ $ 4,295 ​ $ 5,328 ​ $ 13,035 ​ $ 16,838 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-average number of shares used in: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share ​ 9,104,079 ​ 9,212,119 ​ 9,144,463 ​ 9,184,741 ​ Dilutive common stock equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Stock options and restricted stock units ​ 30,010 ​ 83,610 ​ 57,419 ​ 124,679 ​ Diluted earnings per share ​ 9,134,089 ​ 9,295,729 ​ 9,201,882 ​ 9,309,420 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net income per common share, basic ​ $ 0.47 ​ $ 0.58 ​ $ 1.43 ​ $ 1.83 ​ Net income per common share, diluted ​ $ 0.47 ​ $ 0.57 ​ $ 1.42 ​ $ 1.81 ​

Other Comprehensive Income an_2

Other Comprehensive Income and Loss (Tables)	9 Months Ended
	Sep. 30, 2020
Other Comprehensive Income and Loss
Schedule of changes in components of accumulated other comprehensive income and loss, net of taxes	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unfunded Unrealized Pension (Gain)/Loss on (Dollars in thousands) Liability Securities Total Three months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 8,178 ​ $ (315) ​ $ 7,863 ​ Other comprehensive loss, net of taxes ​ ​ — ​ 4 ​ 4 ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ — ​ — ​ Net current period other comprehensive loss ​ — ​ 4 ​ 4 ​ Balances at end of period ​ $ 8,178 ​ $ (311) ​ $ 7,867 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 7,721 ​ $ (521) ​ $ 7,200 ​ Other comprehensive income, net of taxes ​ — ​ (70) ​ (70) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 91 ​ 91 ​ Net current period other comprehensive loss ​ — ​ 21 ​ 21 ​ Balances at end of period ​ $ 7,721 ​ $ (500) ​ $ 7,221 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 8,178 ​ $ (510) ​ $ 7,668 ​ Other comprehensive income, net of taxes ​ — ​ (22) ​ (22) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 221 ​ 221 ​ Net current period other comprehensive loss ​ — ​ 199 ​ 199 ​ Balances at end of period ​ $ 8,178 ​ $ (311) ​ $ 7,867 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balances at beginning of period ​ $ 7,721 ​ $ 88 ​ $ 7,809 ​ Other comprehensive income, net of taxes ​ — ​ (711) ​ (711) ​ Amounts reclassified from other comprehensive income, net of taxes ​ — ​ 123 ​ 123 ​ Net current period other comprehensive income ​ — ​ (588) ​ (588) ​ Balances at end of period ​ $ 7,721 ​ $ (500) ​ $ 7,221 ​
Schedule of tax effect on each component of accumulated other comprehensive loss	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, 2020 2019 Pretax After Tax Pretax After Tax (Dollars in thousands) Amount Tax Amount Amount Tax Amount Unrealized loss (gain) on securities ​ $ 5 ​ $ (1) ​ $ 4 ​ $ (95) ​ $ 25 ​ $ (70) ​ Amount reclassified from other comprehensive income ​ ​ — ​ ​ — ​ ​ — ​ ​ 123 ​ ​ (32) ​ ​ 91 ​ Total ​ $ 5 ​ $ (1) ​ $ 4 ​ $ 28 ​ $ (7) ​ $ 21 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended September 30, ​ 2020 2019 ​ Pretax After Tax Pretax After Tax (Dollars in thousands) Amount Tax Amount Amount Tax Amount Unrealized gain on securities ​ $ (30) ​ $ 8 ​ $ (22) ​ $ (969) ​ $ 258 ​ $ (711) ​ Amount reclassified from other comprehensive income ​ ​ 301 ​ ​ (80) ​ ​ 221 ​ ​ 167 ​ ​ (44) ​ ​ 123 ​ Total ​ $ 271 ​ $ (72) ​ $ 199 ​ $ (802) ​ $ 214 ​ $ (588) ​

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2020
Revenue Recognition
Reconciliation of revenue from contracts with customers and other revenue reported in line items	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Service Fees on ​ ​ ​ ​ Loan and Deposit ​ ​ ​ ​ (Dollars in thousands) Accounts Other Total Three months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 275 ​ $ 35 ​ $ 310 Other revenue ​ ​ 453 ​ ​ 28 ​ ​ 481 Total ​ $ 728 ​ $ 63 ​ $ 791 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 347 ​ $ 37 ​ $ 384 Other revenue ​ ​ 157 ​ ​ 18 ​ ​ 175 Total ​ $ 504 ​ $ 55 ​ $ 559 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 918 ​ $ 88 ​ $ 1,006 Other revenue ​ ​ 798 ​ ​ 83 ​ ​ 881 Total ​ $ 1,716 ​ $ 171 ​ $ 1,887 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended September 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenue from contracts with customers ​ $ 1,047 ​ $ 137 ​ $ 1,184 Other revenue ​ ​ 380 ​ ​ 498 ​ ​ 878 Total ​ $ 1,427 ​ $ 635 ​ $ 2,062

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2020
Leases
Schedule of lease costs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended ​ September 30, September 30, (Dollars in thousands) 2020 2019 2020 2019 Lease Costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating lease costs ​ $ 878 ​ $ 777 ​ $ 2,509 ​ $ 2,342 ​ Short-term lease costs ​ 5 ​ 21 ​ 17 ​ 37 ​ Variable lease costs ​ 38 ​ 40 ​ 115 ​ 93 ​ Total lease costs ​ $ 921 ​ $ 838 ​ $ 2,641 ​ $ 2,472 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash paid for amounts included in measurement of lease liabilities ​ $ 808 ​ $ 721 ​ $ 2,414 ​ $ 2,266 ​ ROU assets obtained in exchange for new operating lease liabilities ​ $ 2,247 ​ $ 246 ​ $ 4,033 ​ $ 13,254 ​ ​
Schedule of future minimum rental commitments under noncancellable operating leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ 2020 ​ $ 820 ​ ​ ​ ​ ​ ​ 2021 ​ 2,974 ​ ​ ​ ​ ​ ​ 2022 ​ 2,690 ​ ​ ​ ​ ​ ​ 2023 ​ 2,339 ​ ​ ​ ​ ​ ​ 2024 ​ 2,060 ​ ​ ​ ​ ​ ​ Thereafter ​ 4,294 ​ ​ ​ ​ ​ ​ Total ​ ​ 15,177 ​ ​ ​ ​ ​ ​ Less present value discount ​ ​ 1,047 ​ ​ ​ ​ ​ ​ Present value of leases ​ $ 14,130 ​ ​ ​ ​ ​ ​ ​
Schedule of other lease related information	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ ​ September 30, ​ ​ ​ 2020 ​ 2019 ​ Weighted-average remaining lease term (years) ​ 6.00 ​ ​ 6.23 ​ ​ Weighted-average discount rate ​ ​ 2.45 % ​ ​ 2.90 % ​

Fair Value (Tables)

Fair Value (Tables)	9 Months Ended
	Sep. 30, 2020
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 September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 237,498 ​ $ 237,498 ​ $ 237,498 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 3,959 ​ ​ 3,959 ​ ​ — ​ ​ 3,959 ​ ​ — ​ Investment securities held to maturity ​ 292,528 ​ ​ 309,471 ​ ​ — ​ ​ 309,471 ​ ​ — ​ Loans held for sale ​ 834 ​ ​ 870 ​ ​ — ​ ​ 870 ​ ​ — ​ Loans receivable, net ​ 1,482,639 ​ ​ 1,562,422 ​ ​ — ​ ​ — ​ ​ 1,562,422 ​ FHLB stock ​ 8,144 ​ ​ 8,144 ​ ​ — ​ ​ 8,144 ​ ​ — ​ FRB stock ​ ​ 3,145 ​ ​ 3,145 ​ ​ — ​ ​ 3,145 ​ ​ — ​ Accrued interest receivable ​ 7,214 ​ ​ 7,214 ​ ​ 19 ​ ​ 794 ​ ​ 6,401 ​ Interest rate contracts ​ 60 ​ ​ 60 ​ ​ — ​ ​ 60 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,662,706 ​ ​ 1,667,045 ​ ​ — ​ ​ 1,285,438 ​ ​ 381,607 ​ Advances from the Federal Home Loan Bank ​ 141,000 ​ ​ 145,623 ​ ​ — ​ ​ 145,623 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 10,484 ​ ​ — ​ ​ 10,484 ​ ​ — ​ Accrued interest payable ​ 99 ​ ​ 99 ​ ​ — ​ ​ 48 ​ ​ 51 ​ Interest rate contracts ​ 60 ​ ​ 60 ​ ​ — ​ ​ 60 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash and cash equivalents ​ $ 44,806 ​ $ 44,806 ​ $ 44,806 ​ $ — ​ $ — ​ Investment securities available for sale ​ ​ 8,628 ​ ​ 8,628 ​ ​ — ​ ​ 8,628 ​ ​ — ​ Investment securities held to maturity ​ 363,883 ​ ​ 371,305 ​ ​ — ​ ​ 371,305 ​ ​ — ​ Loans held for sale ​ 470 ​ ​ 480 ​ ​ — ​ ​ 480 ​ ​ — ​ Loans receivable, net ​ 1,584,784 ​ ​ 1,627,903 ​ ​ — ​ ​ — ​ ​ 1,627,903 ​ FHLB stock ​ 8,723 ​ ​ 8,723 ​ ​ — ​ ​ 8,723 ​ ​ — ​ FRB stock ​ ​ 3,128 ​ ​ 3,128 ​ ​ — ​ ​ 3,128 ​ ​ — ​ Accrued interest receivable ​ 5,409 ​ ​ 5,409 ​ ​ 32 ​ ​ 952 ​ ​ 4,425 ​ Interest rate contracts ​ 5 ​ ​ 5 ​ ​ — ​ ​ 5 ​ ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Deposits ​ 1,631,933 ​ ​ 1,632,741 ​ ​ — ​ ​ 1,167,990 ​ ​ 464,751 ​ Advances from the Federal Home Loan Bank ​ 156,000 ​ ​ 156,906 ​ ​ — ​ ​ 156,906 ​ ​ — ​ Securities sold under agreements to repurchase ​ 10,000 ​ ​ 9,968 ​ ​ — ​ ​ 9,968 ​ ​ — ​ Accrued interest payable ​ 397 ​ ​ 397 ​ ​ — ​ ​ 47 ​ ​ 350 ​ Interest rate contracts ​ 5 ​ ​ 5 ​ ​ — ​ ​ 5 ​ ​ — ​
Schedule of assets and liabilities measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (Dollars in thousands) Level 1 Level 2 Level 3 Total September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts — assets ​ $ — ​ $ 60 ​ $ — ​ $ 60 ​ Interest rate contracts — liabilities ​ — ​ (60) ​ — ​ (60) ​ Investment securities available for sale ​ ​ — ​ ​ 3,959 ​ ​ — ​ ​ 3,959 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest rate contracts — assets ​ $ — ​ $ 5 ​ $ — ​ $ 5 ​ Interest rate contracts — liabilities ​ — ​ (5) ​ — ​ (5) ​ Investment securities available for sale ​ — ​ 8,628 ​ — ​ 8,628 ​
Schedule of Significant unobservable inputs for Level 3 nonrecurring fair value measurements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Unobservable Range (Dollars in thousands) Fair Value Valuation Technique Input (Weighted Average) September 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ $ 452 ​ Discounted cash flow ​ Discount rate ​ ​ 9.25% - 11.25% (10.25%) ​ ​ ​ ​ ​ ​ ​ ​ Prepayment speed (CPR) ​ 9.36 - 18.16 (13.54) ​ ​ ​ ​ ​ ​ ​ ​ Annual cost to service (per loan, in dollars) ​ $ 75 ​ December 31, 2019: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ $ 452 Discounted cash flow Discount rate ​ ​ 9.25% - 11.25% (10.25%) ​ ​ ​ ​ ​ ​ ​ Prepayment speed (CPR) ​ 11.09 - 14.24 (12.58) ​ ​ ​ ​ ​ ​ ​ Annual cost to service (per loan, in dollars) ​ $ 75 ​
Fair Value, Measurements, Nonrecurring
Schedule of balance of assets measured at fair value on a nonrecurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value ​ ​ (Dollars in thousands) Adjustment Date ​ Level 1 Level 2 Level 3 Total ​ Total Losses ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ 9/30/2020 ​ $ — ​ $ — ​ $ 452 ​ $ 452 ​ $ (53) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Mortgage servicing assets ​ 9/30/2019 ​ ​ — ​ ​ — ​ ​ 452 ​ ​ 452 ​ ​ (16) ​

Cash and Cash Equivalents (Deta

Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Cash and Cash Equivalents
Cash and due from banks	$ 10,873	$ 9,571
Interest-earning deposits in other banks	226,625	35,235
Cash and cash equivalents	$ 237,498	$ 44,806

Investment Securities - Amortiz

Investment Securities - Amortized Cost and Fair Values of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Available-for-sale:
Amortized Cost	$ 3,534	$ 7,905
Gross Unrealized Gains	425	723
Estimated Fair Value	3,959	8,628
Mortgage-backed securities
Available-for-sale:
Amortized Cost	3,534	7,905
Gross Unrealized Gains	425	723
Estimated Fair Value	$ 3,959	$ 8,628

Investment Securities - Amort_2

Investment Securities - Amortized Cost and Fair Values of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Held-to-maturity:
Amortized Cost	$ 292,528	$ 363,883
Gross Unrealized Gains	16,945	8,436
Gross Unrealized Losses	(2)	(1,014)
Estimated Fair Value	309,471	371,305
Mortgage-backed securities
Held-to-maturity:
Amortized Cost	292,528	363,883
Gross Unrealized Gains	16,945	8,436
Gross Unrealized Losses	(2)	(1,014)
Estimated Fair Value	$ 309,471	$ 371,305

Investment Securities - Maturit

Investment Securities - Maturity Schedule of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortized Cost
Due within 5 years	$ 0
Due after 5 years through 10 years	0
Due after 10 years	3,534
Amortized Cost	3,534	$ 7,905
Estimated Fair Value
Due within 5 years	0
Due after 5 years through 10 years	0
Due after 10 years	3,959
Estimated Fair Value	$ 3,959	$ 8,628

Investment Securities - Matur_2

Investment Securities - Maturity Schedule of Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Held-to-maturity, Amortized Cost
Due within 5 years	$ 0
Due after 5 years through 10 years	62
Due after 10 years	292,466
Amortized Cost	292,528	$ 363,883
Held-to-maturity, Estimated Fair Value
Due within 5 years	0
Due after 5 years through 10 years	61
Due after 10 years	309,410
Estimated Fair Value	$ 309,471	$ 371,305

Investment Securities - Realize

Investment Securities - Realized Gains and Losses and Proceeds from Sales (Details) - USD ($)	Jan. 01, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales				$ 10,429,000	$ 3,527,000
Available-for-sale mortgage-backed securities sold				3,400,000	5,000,000
Transfer of securities from held-to-maturity to available-for-sale	$ 11,400,000				11,390,000
Trust preferred securities
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales					75,000
Gross gains					2,700,000
Mortgage-backed securities
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales					746,000
Gross gains				568,000	40,000
Debt Securities, Available-for-sale, Realized Gain				290,000	153,000
Mortgage-backed securities
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales				$ 9,900,000
Minimum | Mortgage-backed securities
Realized gains and losses and the proceeds from sales of securities
Portion of outstanding purchased principal already collected				85.00%
Held-to-maturity debt securities
Realized gains and losses and the proceeds from sales of securities
Proceeds from sales		$ 5,737,000	$ 4,308,000	$ 14,097,000	8,644,000
Gross gains		$ 261,000	$ 123,000	$ 858,000	$ 2,910,000

Investment Securities - Securit

Investment Securities - Securities Pledged (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Pledged investment securities
Investment securities pledged to secure deposits made by state and local governments, securities sold under agreements to repurchase and transaction clearing accounts	$ 217.5	$ 188.9

Investment Securities - Held-to

Investment Securities - Held-to-Maturity Unrealized Loss Position Summary (Details) - Mortgage-backed securities $ in Thousands	Sep. 30, 2020USD ($)security	Dec. 31, 2019USD ($)security
Investment Securities
Less Than 12 Months Fair Value	$ 958	$ 55,882
Less Than 12 Months Unrealized Losses	(1)	(302)
12 Months or Longer Fair Value	4	34,492
12 Months or Longer Unrealized Losses	$ (1)	$ (712)
Total Number of Securities | security	6	30
Total Fair Value	$ 962	$ 90,374
Total Unrealized Losses	$ (2)	$ (1,014)

Investment Securities - Mortgag

Investment Securities - Mortgage-Backed Securities (Details)	9 Months Ended
	Sep. 30, 2020USD ($)
Schedule of Investments [Line Items]
Fair market value of received mortgage-backed securities	$ 9,800,000
Mortgage servicing assets	78,000
Net gain recognized on the securitization	377,000
Fixed-rate mortgage loans
Schedule of Investments [Line Items]
Book value	9,400,000
Mortgage servicing assets	78,000
Net gain recognized on the securitization	$ 377,000

Loans Receivable and Allowanc_3

Loans Receivable and Allowance for Loan Losses - Components (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Real estate loans:
Total real estate loans	$ 1,477,751		$ 1,580,212
Other loans:
Less: Net unearned fees and discounts	(1,917)		(2,435)
Less: Allowance for loan losses	(4,942)	$ (4,256)	(2,712)	$ (2,724)	$ (2,616)	$ (2,642)
Total unearned fees, discounts and allowance for loan losses	(6,859)		(5,147)
Loans receivable, net	1,482,639		1,584,784
Other Financing Receivables
Other loans:
Total other loans	11,747		9,719
One- to four-family residential | Residential Mortgage
Real estate loans:
Total real estate loans	1,436,900		1,536,781
Multi-family residential | Residential Mortgage
Real estate loans:
Total real estate loans	8,897		9,965
Construction, Commercial and Other Mortgage Loans | Construction, commercial and other
Real estate loans:
Total real estate loans	22,250		23,382
Other loans:
Less: Allowance for loan losses	(457)	(459)	(511)	(501)	(411)	(443)
Home Equity Loans and Lines of Credit | Home equity loans and lines of credit
Real estate loans:
Total real estate loans	9,704		10,084
Other loans:
Less: Allowance for loan losses	(1)	$ (1)	(1)	$ (1)	$ (1)	$ (1)
Loans on Deposit Accounts | Other Financing Receivables
Other loans:
Total other loans	272		235
Consumer and Other | Other Financing Receivables
Other loans:
Total other loans	$ 11,475		$ 9,484

Loans Receivable and Allowanc_4

Loans Receivable and Allowance for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Activity in allowance for loan losses
Balance, beginning of period	$ 4,256,000	$ 2,616,000	$ 2,712,000	$ 2,642,000
Provision (reversal of provision) for loan losses	692,000	111,000	2,304,000	65,000
Allowance for loan losses on loans receivable after provision (reversal of allowance)	4,948,000	2,727,000	5,016,000	2,707,000
Charge-offs	(6,000)	(5,000)	(86,000)	(21,000)
Recoveries		2,000	12,000	38,000
Net recoveries (charge-offs)	(6,000)	(3,000)	(74,000)	17,000
Balance, end of period	4,942,000	2,724,000	4,942,000	2,724,000
Residential Mortgage | Residential Mortgage
Activity in allowance for loan losses
Balance, beginning of period	3,020,000	1,769,000	1,741,000	1,797,000
Provision (reversal of provision) for loan losses	988,000	(11,000)	2,267,000	(57,000)
Allowance for loan losses on loans receivable after provision (reversal of allowance)	4,008,000	1,758,000	4,008,000	1,740,000
Recoveries				18,000
Net recoveries (charge-offs)				18,000
Balance, end of period	4,008,000	1,758,000	4,008,000	1,758,000
Construction, commercial and other | Construction, Commercial and Other Mortgage Loans
Activity in allowance for loan losses
Balance, beginning of period	459,000	411,000	511,000	443,000
Provision (reversal of provision) for loan losses	(2,000)	90,000	(54,000)	58,000
Allowance for loan losses on loans receivable after provision (reversal of allowance)	457,000	501,000	457,000	501,000
Balance, end of period	457,000	501,000	457,000	501,000
Home equity loans and lines of credit | Home Equity Loans and Lines of Credit
Activity in allowance for loan losses
Balance, beginning of period	1,000	1,000	1,000	1,000
Provision (reversal of provision) for loan losses			(10,000)
Allowance for loan losses on loans receivable after provision (reversal of allowance)	1,000	1,000	(9,000)	1,000
Recoveries			10,000
Net recoveries (charge-offs)			10,000
Balance, end of period	1,000	1,000	1,000	1,000
Other Financing Receivables | Consumer and other loans
Activity in allowance for loan losses
Balance, beginning of period	197,000	44,000	54,000	47,000
Provision (reversal of provision) for loan losses	(21,000)	15,000	200,000	10,000
Allowance for loan losses on loans receivable after provision (reversal of allowance)	176,000	59,000	254,000	57,000
Charge-offs	(6,000)	(5,000)	(86,000)	(21,000)
Recoveries		2,000	2,000	20,000
Net recoveries (charge-offs)	(6,000)	(3,000)	(84,000)	(1,000)
Balance, end of period	170,000	56,000	170,000	56,000
Unallocated | Unallocated
Activity in allowance for loan losses
Balance, beginning of period	579,000	391,000	405,000	354,000
Provision (reversal of provision) for loan losses	(273,000)	17,000	(99,000)	54,000
Allowance for loan losses on loans receivable after provision (reversal of allowance)	306,000	408,000	306,000	408,000
Balance, end of period	$ 306,000	$ 408,000	$ 306,000	$ 408,000

Loans Receivable and Allowanc_5

Loans Receivable and Allowance for Loan Losses - Balance in Allowance for Loan Losses and Recorded Investment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Allowance for loan losses:
Collectively evaluated for impairment	$ 4,942		$ 2,712
Total ending allowance balance	4,942	$ 4,256	2,712	$ 2,724	$ 2,616	$ 2,642
Loans:
Individually evaluated for impairment	2,755		1,313
Collectively evaluated for impairment	1,484,826		1,586,183
Total ending loan balance	1,487,581		1,587,496
Residential Mortgage | Residential Mortgage
Allowance for loan losses:
Collectively evaluated for impairment	4,008		1,741
Total ending allowance balance	4,008	3,020	1,741	1,758	1,769	1,797
Loans:
Individually evaluated for impairment	2,732		1,224
Collectively evaluated for impairment	1,441,193		1,543,125
Total ending loan balance	1,443,925		1,544,349
Construction, commercial and other | Construction, Commercial and Other Mortgage Loans
Allowance for loan losses:
Collectively evaluated for impairment	457		511
Total ending allowance balance	457	459	511	501	411	443
Loans:
Collectively evaluated for impairment	22,191		23,326
Total ending loan balance	22,191		23,326
Home equity loans and lines of credit | Home Equity Loans and Lines of Credit
Allowance for loan losses:
Collectively evaluated for impairment	1		1
Total ending allowance balance	1	1	1	1	1	1
Loans:
Individually evaluated for impairment	23		89
Collectively evaluated for impairment	9,682		9,997
Total ending loan balance	9,705		10,086
Other Financing Receivables | Consumer and other loans
Allowance for loan losses:
Collectively evaluated for impairment	170		54
Total ending allowance balance	170	197	54	56	44	47
Loans:
Collectively evaluated for impairment	11,760		9,735
Total ending loan balance	11,760		9,735
Unallocated | Unallocated
Allowance for loan losses:
Collectively evaluated for impairment	306		405
Total ending allowance balance	$ 306	$ 579	$ 405	$ 408	$ 391	$ 354

Loans Receivable and Allowanc_6

Loans Receivable and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Impaired loans
Average Recorded Investment	$ 2,769	$ 1,460	$ 2,795	$ 1,491
Interest Income Recognized	8	8	25	25
One- to four-family residential
Impaired loans
Average Recorded Investment	2,745	1,364	2,770	1,391
Interest Income Recognized	8	8	25	25
Home Equity Loans and Lines of Credit
Impaired loans
Average Recorded Investment	24	$ 96	25	$ 100
Individually Evaluated for Impairment
Impaired loans
Recorded Investment	2,755		2,755		$ 1,313
Unpaid Principal Balance	3,196		3,196		1,793
Loans individually evaluated for impairment with a related allowance for loan loss	0		0		0
Individually Evaluated for Impairment | One- to four-family residential
Impaired loans
Recorded Investment	2,732		2,732		1,224
Unpaid Principal Balance	3,164		3,164		1,615
Individually Evaluated for Impairment | Home Equity Loans and Lines of Credit
Impaired loans
Recorded Investment	23		23		89
Unpaid Principal Balance	$ 32		$ 32		$ 178

Loans Receivable and Allowanc_7

Loans Receivable and Allowance for Loan Losses - Delinquent and Nonaccrual Loans (Details)	9 Months Ended
	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)loan
Accounts, Notes, Loans and Financing Receivable
Nonaccrual Loans	$ 2,186,000		$ 736,000
90 Days or More Past Due
Accounts, Notes, Loans and Financing Receivable
Number of loans | loan			1
Mortgage loan due			$ 1,000
Fixed-rate mortgage loans | Minimum
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
Non Accrual Loans
Accounts, Notes, Loans and Financing Receivable
Number of loans | loan	8		6
Nonaccrual Loans	$ 2,200,000		$ 736,000
Interest collected on nonaccrual loans recorded as a reduction of principal	40,000	$ 51,000
Non accrual loans, additional interest income that would have been recognized had the loans been accruing interest	$ 68,000	$ 51,000

Loans Receivable and Allowanc_8

Loans Receivable and Allowance for Loan Losses - Aging of Loans and Accrual Status (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 291	$ 1,020
Loans Not Past Due	1,487,290	1,586,476
Total ending loan balance	1,487,581	1,587,496
Nonaccrual Loans	2,186	736
Loans 90 Days or More Past Due and Still Accruing		1
30 - 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	6	33
60 - 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	163	986
90 Days or More Past Due
Financing Receivable, Recorded Investment, Past Due
Total Past Due	122	1
Residential Mortgage | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Past Due	262	959
Loans Not Past Due	1,434,781	1,533,446
Total ending loan balance	1,435,043	1,534,405
Nonaccrual Loans	2,163	647
Residential Mortgage | Multi-family residential
Financing Receivable, Recorded Investment, Past Due
Loans Not Past Due	8,882	9,944
Total ending loan balance	8,882	9,944
Residential Mortgage | 60 - 89 Days Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Past Due	140	959
Residential Mortgage | 90 Days or More Past Due | One- to four-family residential
Financing Receivable, Recorded Investment, Past Due
Total Past Due	122
Construction, commercial and other | Construction, Commercial and Other Mortgage Loans
Financing Receivable, Recorded Investment, Past Due
Loans Not Past Due	22,191	23,326
Total ending loan balance	22,191	23,326
Home equity loans and lines of credit | Home Equity Loans and Lines of Credit
Financing Receivable, Recorded Investment, Past Due
Total Past Due	23	26
Loans Not Past Due	9,682	10,060
Total ending loan balance	9,705	10,086
Nonaccrual Loans	23	89
Home equity loans and lines of credit | 60 - 89 Days Past Due | Home Equity Loans and Lines of Credit
Financing Receivable, Recorded Investment, Past Due
Total Past Due	23	26
Other Financing Receivables | Loans on Deposit Accounts
Financing Receivable, Recorded Investment, Past Due
Loans Not Past Due	272	235
Total ending loan balance	272	235
Other Financing Receivables | Consumer and Other
Financing Receivable, Recorded Investment, Past Due
Total Past Due	6	35
Loans Not Past Due	11,482	9,465
Total ending loan balance	11,488	9,500
Loans 90 Days or More Past Due and Still Accruing		1
Other Financing Receivables | 30 - 59 Days Past Due | Consumer and Other
Financing Receivable, Recorded Investment, Past Due
Total Past Due	$ 6	33
Other Financing Receivables | 60 - 89 Days Past Due | Consumer and Other
Financing Receivable, Recorded Investment, Past Due
Total Past Due		1
Other Financing Receivables | 90 Days or More Past Due | Consumer and Other
Financing Receivable, Recorded Investment, Past Due
Total Past Due		$ 1

Loans Receivable and Allowanc_9

Loans Receivable and Allowance for Loan Losses - Troubled Debt Restructurings (Details)	9 Months Ended		12 Months Ended
	Sep. 30, 2020USD ($)loan	Sep. 30, 2019loan	Dec. 31, 2019USD ($)loan
Troubled debt restructurings
Number of loans subsequently defaulted | loan	0		0
Additional disclosures
Loans modified by troubled debt restructurings considered impaired	$ 1,049,000		$ 1,166,000
Loan deferrals granted, COVID-19	$ 146,200,000
Percentage of forbearance loans representing total loans receivable, COVID-19	9.90%
Percentage of current loan balance to the current tax-assessed value of the property securing mortgage loans COVID-19	54.90%
Real estate owned	$ 0		$ 0
Mortgage loans in process of foreclosure, number of contracts | loan	0		0
Accruing interest
Additional disclosures
Number of loans modified by troubled debt restructurings considered impaired | loan	3		3
Loans modified by troubled debt restructurings considered impaired	$ 568,000		$ 577,000
Non Accrual Loans
Additional disclosures
Number of loans modified by troubled debt restructurings considered impaired | loan	2		3
Loans modified by troubled debt restructurings considered impaired	$ 481,000		$ 589,000
Loans modified in troubled debt restructuring
Troubled debt restructurings
Number of Loans | loan	0	0
Number of loans subsequently defaulted | loan	0		0
Additional disclosures
Commitments to lend additional funds to borrowers	$ 0
One- to four-family residential
Additional disclosures
Loans modified by troubled debt restructurings considered impaired	$ 1,049,000		$ 1,102,000
One- to four-family residential | Accruing interest
Additional disclosures
Number of loans modified by troubled debt restructurings considered impaired | loan	3		3
Loans modified by troubled debt restructurings considered impaired	$ 568,000		$ 577,000
One- to four-family residential | Non Accrual Loans
Additional disclosures
Number of loans modified by troubled debt restructurings considered impaired | loan	2		2
Loans modified by troubled debt restructurings considered impaired	$ 481,000		$ 525,000
Home Equity Loans and Lines of Credit
Additional disclosures
Loans modified by troubled debt restructurings considered impaired			$ 64,000
Home Equity Loans and Lines of Credit | Non Accrual Loans
Additional disclosures
Number of loans modified by troubled debt restructurings considered impaired | loan			1
Loans modified by troubled debt restructurings considered impaired			$ 64,000
Residential Mortgage | One- to four-family residential
Additional disclosures
Loan deferrals granted, COVID-19	$ 140,900,000
Percentage of forbearance loans representing total loans receivable, COVID-19	9.50%
Percentage of current loan balance to the current tax-assessed value of the property securing mortgage loans COVID-19	45.50%
Percentage of mortgage loans representing total loan portfolio balance	96.90%
Unallocated
Additional disclosures
Loan deferrals granted, COVID-19	$ 5,300,000
Percentage of forbearance loans representing total loans receivable, COVID-19	0.40%

Loans Receivable and Allowan_10

Loans Receivable and Allowance for Loan Losses - Collateral, Sales, Serviced for Others, Directors and Executive Officers (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)loan	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)loan
Accounts, Notes, Loans and Financing Receivable
Loans serviced for others	$ 62,700,000		$ 62,700,000		$ 65,100,000
Fair market value of received mortgage-backed securities	9,800,000		9,800,000
Mortgage servicing assets	78,000		78,000
Net gain recognized on the securitization			377,000
Loans serviced for others, securitization for which the company continues to hold the related mortgage-backed securities	40,100,000		40,100,000		$ 37,800,000
Loans serviced for others, amount of contractually specified servicing fees earned	$ 43,000	$ 31,000	$ 134,000	$ 71,000
Fixed-rate mortgage loans | Maximum
Accounts, Notes, Loans and Financing Receivable
Loan to value ratio (as a percent)	80.00%		80.00%
Residential Mortgage Loans Held For Sale
Accounts, Notes, Loans and Financing Receivable
Residential mortgage loans sold, loan amount			$ 22,300,000	3,600,000
Residential mortgage loans sold, recognized gains			$ 610,000	$ 18,000
Number of loans | loan	2		2		1
Residential mortgage loans held for sale	$ 834,000		$ 834,000		$ 470,000
Fixed-rate mortgage loans
Accounts, Notes, Loans and Financing Receivable
Book value	9,400,000		9,400,000
Mortgage servicing assets	$ 78,000		78,000
Net gain recognized on the securitization			$ 377,000

Securities Sold Under Agreeme_3

Securities Sold Under Agreements to Repurchase - Summary of Repurchase Liability by Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
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%	1.77%
1 year or less
Securities sold under agreements to repurchase
Repurchase Liability		$ 5,000
1 year or less | Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)		1.65%
Over 4 years to 5 years
Securities sold under agreements to repurchase
Repurchase Liability	$ 10,000	$ 5,000
Over 4 years to 5 years | Weighted Average
Securities sold under agreements to repurchase
Rate (as a percent)	1.81%	1.88%

Securities Sold Under Agreeme_4

Securities Sold Under Agreements to Repurchase - Summary of Securities Pledged (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020USD ($)
Securities sold under agreements to repurchase
Repurchase liability maximum	90.00%
Maturing Over 90 days
Securities sold under agreements to repurchase
Carrying Value of Securities	$ 10,001
Fair Value of Securities	10,994
Repurchase Liability	10,000
Amount at Risk	$ 994
Weighted Average Months to Maturity	51 months

Offsetting of Financial Liabi_3

Offsetting of Financial Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
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 Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net periodic benefit cost (income) for the year:
Service cost	$ 22	$ 26
Interest cost	43	41
Net periodic benefit cost	$ 65	$ 67
Pension Plan | Minimum
Pension and Other Postretirement Benefit Contributions
Requisite service period for receiving benefits under the plan			1 year
Supplemental Employee Retirement Plan (SERP)
Net periodic benefit cost (income) for the year:
Service cost			$ 66	$ 77
Interest cost			130	122
Net periodic benefit cost			$ 196	$ 199

Employee Stock Ownership Plan -

Employee Stock Ownership Plan - Loan, Expense and Shares (Details) - USD ($)	Jan. 01, 2009	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Employee Stock Ownership Plan
Allocated shares		495,070		495,070		466,807
Unearned shares		403,698		403,698		440,397
Total ESOP shares		898,768		898,768		907,204
Fair value of unearned shares, in thousands		$ 8,167,000		$ 8,167,000		$ 13,626,000
ESOP
Employee Stock Ownership Plan
Amount borrowed from employer	$ 9,800,000
Shares purchased	978,650
Percentage of shares issued in initial public offering	8.00%
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		$ 264,000	$ 350,000	$ 905,000	$ 1,000,000
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		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
ESOP restoration | Certain executives
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits
Accrued (reversed) benefits	$ 5,000	$ 67,000	$ 79,000	$ 246,000

Share-Based Compensation - Plan

Share-Based Compensation - Plan Provisions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-Based Compensation
Compensation expense	$ 157	$ 123	$ 523	$ 494
Income tax benefit	$ 43	$ 33	$ 143	$ 135
Number of shares authorized	1,862,637		1,862,637
2010 Equity Incentive Plan | Vesting period one
Share-Based Compensation
Vesting period			3 years
2010 Equity Incentive Plan | Vesting period two
Share-Based Compensation
Vesting period			5 years
2010 Equity Incentive Plan | Vesting period three
Share-Based Compensation
Vesting period			6 years

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Common Stock
Stock option activity
Exercised (in shares)	21,200	81,827	203,370
Stock option activity
Shares of common stock issued in exchange for stock options and common shares		27,194
Common shares exchanged		54,633
Stock Options
Stock option activity
Balance at beginning of period (in shares)		116,409	337,654	337,654
Exercised (in shares)		81,827	203,370
Expired (in shares)		31,497
Balance at end of period (in shares)	134,284	3,085	134,284	116,409	337,654
Options vested and exercisable (in shares)		3,085
Weighted Average Exercise Price
Balance at beginning of period (in dollars per share)		$ 17.53	$ 17.51	$ 17.51
Exercised (in dollars per share)		17.36	17.36
Balance at end of period (in dollars per share)	$ 17.74	23.62	$ 17.74	$ 17.53	$ 17.51
Options vested and exercisable (in dollars per share)		$ 23.62
Remaining Contractual Life
Options outstanding		1 year 11 months 1 day	1 year 1 month 6 days	8 months 19 days	1 year 8 months 26 days
Options vested and exercisable		1 year 11 months 1 day
Aggregate Intrinsic Value
Beginning of period		$ 1,562	$ 2,859	$ 2,859
Exercised	$ 251	725	2,282
End of period	1,455	(11)	1,455	$ 1,562	$ 2,859
Options vested and exercisable		(11)
Stock option activity
Intrinsic value of stock options exercised	251	725	2,282
Proceeds received from stock options exercised	368	1,421	3,531
Tax benefits realized from stock options exercised	$ 60	$ 158	$ 484
Common shares exchanged		81,827
Unrecognized compensation costs		$ 0

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Awards (Details) - USD ($)	Mar. 12, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Restricted Stock
Restricted Stock Awards
Unvested at beginning of period (in shares)		20,249	16,424
Granted (in shares)		13,444	10,366
Vested (in shares)		9,998	6,541
Unvested at end of period (in shares)		23,695	20,249
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)		$ 28.78	$ 30.26
Granted (in dollars per share)		21.05	27.30
Vested (in dollars per share)		29.16	30.14
Unvested at end of period (in dollars per share)		$ 24.24	$ 28.78
Unrecognized compensation
Vesting period		3 years
Unrecognized compensation costs		$ 410,000
Restricted Stock Units Based on a Performance Condition
Restricted Stock Awards
Unvested at beginning of period (in shares)		35,976	23,538
Granted (in shares)		16,129	12,438
Vested (in shares)		7,680
Forfeited (in shares)		3,840
Unvested at end of period (in shares)		40,585	35,976
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)		$ 29.16	$ 30.14
Granted (in dollars per share)		21.05	27.30
Vested (in dollars per share)		29.53
Forfeited (in dollars per share)		29.53
Unvested at end of period (in dollars per share)		$ 25.83	$ 29.16
Unrecognized compensation
Unrecognized compensation costs		$ 428,000
Unrecognized compensation costs, period of recognition		3 years
Restricted Stock Units Based on a Performance Condition | Minimum
Unrecognized compensation
Shares vesting as a percentage of target		0.00%
Restricted Stock Units Based on a Performance Condition | Maximum
Unrecognized compensation
Shares vesting as a percentage of target		150.00%
Restricted Stock Units Based on a Market Condition
Restricted Stock Awards
Unvested at beginning of period (in shares)		8,994	5,884
Granted (in shares)		4,032	3,110
Vested (in shares)		1,197
Forfeited (in shares)		1,682
Unvested at end of period (in shares)		10,147	8,994
Weighted Average Grant Date Fair Value
Unvested at beginning of period (in dollars per share)		$ 25.74	$ 26.42
Granted (in dollars per share)		22.16	24.45
Vested (in dollars per share)		24.44
Forfeited (in dollars per share)		24.44
Unvested at end of period (in dollars per share)		$ 24.69	$ 25.74
Unrecognized compensation
Unrecognized compensation costs		$ 90,000
Unrecognized compensation costs, period of recognition		3 years
Assumptions used in the Monte Carlo valuation of PRSUs
Term used for risk-free rate	2 years 9 months 18 days
Term used for risk-free rate and historical volatility	2 years 9 months 25 days
Risk-free interest rate (as a percent)	0.56%
Closing stock price (in dollars per share)	$ 21.05			$ 30.94
Annualized volatility (as a percent)	18.02%

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share
Net income	$ 4,318	$ 5,366	$ 13,082	$ 16,950
Income allotted to participating securities	(23)	(38)	(47)	(112)
Net income available to common shareholders	$ 4,295	$ 5,328	$ 13,035	$ 16,838
Weighted-average number of shares used in:
Basic earnings per share (in shares)	9,104,079	9,212,119	9,144,463	9,184,741
Dilutive common stock equivalents:
Stock options and restricted stock units (in shares)	30,010	83,610	57,419	124,679
Diluted earnings per share (in shares)	9,134,089	9,295,729	9,201,882	9,309,420
Net income per common share, basic (in dollars per share)	$ 0.47	$ 0.58	$ 1.43	$ 1.83
Net income per common share, diluted (in dollars per share)	$ 0.47	$ 0.57	$ 1.42	$ 1.81

Other Comprehensive Income an_3

Other Comprehensive Income and Loss - Changes in Components of Accumulated Other Comprehensive Income and Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	$ (244,027)	$ (241,772)	$ (243,890)	$ (235,079)
Other comprehensive income, net of taxes	4	21	199	(588)
Balances at end of period	(246,658)	(245,602)	(246,658)	(245,602)
Accumulated Other Comprehensive Loss
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	7,863	7,200	7,668	7,809
Other comprehensive income, net of taxes	4	21	199	(588)
Net current period other comprehensive (gain) loss	4	21	199	(588)
Balances at end of period	7,867	7,221	7,867	7,221
Other comprehensive income, net of taxes
Changes in the components of accumulated other comprehensive loss, net of taxes
Other comprehensive income, net of taxes	4	(70)	(22)	(711)
Unfunded Pension Liability
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	8,178	7,721	8,178	7,721
Balances at end of period	8,178	7,721	8,178	7,721
Amount Reclassified from Other Comprehensive Income
Changes in the components of accumulated other comprehensive loss, net of taxes
Other comprehensive income, net of taxes		91	221	123
Amounts reclassified from accumulated other comprehensive income, net of taxes		(91)	(221)	(123)
Unrealized (Gain)/Loss on Securities
Changes in the components of accumulated other comprehensive loss, net of taxes
Balances at beginning of period	(315)	(521)	(510)	88
Other comprehensive income, net of taxes	4	(70)	(22)	(711)
Net current period other comprehensive (gain) loss		21	199	(588)
Balances at end of period	$ (311)	$ (500)	$ (311)	$ (500)

Other Comprehensive Income an_4

Other Comprehensive Income and Loss - Tax Effect on Each Component (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Tax effect on each component of other comprehensive loss
Pretax amount	$ 5	$ 28	$ 271	$ (802)
Tax	(1)	(7)	(72)	(214)
After Tax Amount	4	21	199	(588)
Unrealized (Gain)/Loss on Securities
Tax effect on each component of other comprehensive loss
Pretax amount	5	(95)	(30)	(969)
Tax	(1)	25	8	(258)
After Tax Amount	$ 4	(70)	(22)	(711)
Amount Reclassified from Other Comprehensive Income
Tax effect on each component of other comprehensive loss
Pretax amount		123	301	167
Tax		(32)	(80)	44
After Tax Amount		$ 91	$ 221	$ 123

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues
Revenue from contracts with customers	$ 310	$ 384	$ 1,006	$ 1,184
Other revenue	481	175	881	878
Total revenue from contracts with customers and other revenue	791	559	1,887	2,062
Service Fees on Loan and Deposit Accounts
Revenues
Revenue from contracts with customers	275	347	918	1,047
Other revenue	453	157	798	380
Total	728	504	1,716	1,427
Other
Revenues
Revenue from contracts with customers	35	37	88	137
Other revenue	28	18	83	498
Total other noninterest income	$ 63	$ 55	$ 171	$ 635

Leases - Lease Costs (Details)

Leases - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Leases
Election to use package of lease practical expedients			true
Lease costs:
Operating lease costs	$ 878	$ 777	$ 2,509	$ 2,342
Short-term lease costs	5	21	17	37
Variable lease costs	38	40	115	93
Total lease costs	921	838	2,641	2,472
Cash paid for amounts included in measurement of lease liabilities	808	721	2,414	2,266
Establishment of right-of-use asset, net of incentives	2,247	$ 246	4,033	$ 13,254
Rental expense, minimum rentals	$ 15,177		$ 15,177

Leases - Future Minimum Rental

Leases - Future Minimum Rental Commitments Under Non-cancellable Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Future minimum rental commitments:
2020	$ 820
2021	2,974
2022	2,690
2023	2,339
2024	2,060
Thereafter	4,294
Total	15,177
Less present value discount	1,047
Present value of leases	$ 14,130	$ 12,183

Leases - Other Related Informat

Leases - Other Related Information (Details)	Sep. 30, 2020	Sep. 30, 2019
Leases
Weighted-average remaining lease term (years)	6 years	6 years 2 months 23 days
Weighted-average discount rate	2.45%	2.90%

Fair Value - Estimated Fair Val

Fair Value - Estimated Fair Values (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets
Investment securities available for sale, at fair value	$ 3,959	$ 8,628
Investment securities held to maturity	309,471	371,305
Carrying Amount
Assets
Cash and cash equivalents	237,498	44,806
Investment securities available for sale, at fair value	3,959	8,628
Investment securities held to maturity	292,528	363,883
Loans held for sale	834	470
Loans receivable, net	1,482,639	1,584,784
FHLB stock	8,144	8,723
FRB stock	3,145	3,128
Accrued interest receivable	7,214	5,409
Interest rate contracts	60	5
Liabilities
Deposits	1,662,706	1,631,933
Advances from the Federal Home Loan Bank	141,000	156,000
Securities sold under agreements to repurchase	10,000	10,000
Accrued interest payable	99	397
Interest rate contracts	60	5
Estimated Fair Value
Assets
Cash and cash equivalents	237,498	44,806
Investment securities available for sale, at fair value	3,959	8,628
Investment securities held to maturity	309,471	371,305
Loans held for sale	870	480
Loans receivable, net	1,562,422	1,627,903
FHLB stock	8,144	8,723
FRB stock	3,145	3,128
Accrued interest receivable	7,214	5,409
Interest rate contracts	60	5
Liabilities
Deposits	1,667,045	1,632,741
Advances from the Federal Home Loan Bank	145,623	156,906
Securities sold under agreements to repurchase	10,484	9,968
Accrued interest payable	99	397
Interest rate contracts	60	5
Estimated Fair Value | Level 1
Assets
Cash and cash equivalents	237,498	44,806
Accrued interest receivable	19	32
Estimated Fair Value | Level 2
Assets
Investment securities available for sale, at fair value	3,959	8,628
Investment securities held to maturity	309,471	371,305
Loans held for sale	870	480
FHLB stock	8,144	8,723
FRB stock	3,145	3,128
Accrued interest receivable	794	952
Interest rate contracts	60	5
Liabilities
Deposits	1,285,438	1,167,990
Advances from the Federal Home Loan Bank	145,623	156,906
Securities sold under agreements to repurchase	10,484	9,968
Accrued interest payable	48	47
Interest rate contracts	60	5
Estimated Fair Value | Level 3
Assets
Loans receivable, net	1,562,422	1,627,903
Accrued interest receivable	6,401	4,425
Liabilities
Deposits	381,607	464,751
Accrued interest payable	$ 51	$ 350

Fair Value - Recurring Basis (D

Fair Value - Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Assets and Liabilities Measured at Fair Value on Recurring Basis
Investment securities available for sale, at fair value	$ 3,959	$ 8,628
Fair Value, Measurements, Recurring
Assets and Liabilities Measured at Fair Value on Recurring Basis
Interest rate contracts - assets	60	5
Interest rate contracts - liabilities	(60)	(5)
Investment securities available for sale, at fair value	3,959	8,628
Fair Value, Measurements, Recurring | Level 2
Assets and Liabilities Measured at Fair Value on Recurring Basis
Interest rate contracts - assets	60	5
Interest rate contracts - liabilities	(60)	(5)
Investment securities available for sale, at fair value	$ 3,959	$ 8,628

Fair Value - Nonrecurring Basis

Fair Value - Nonrecurring Basis (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)
Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Valuation Technique [Extensible List]	us-gaap:ValuationTechniqueDiscountedCashFlowMember	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Fair Value, Measurements, Nonrecurring
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Mortgage servicing assets, Fair value	$ 452	$ 452
Mortgage servicing assets, Total losses	(53)	(16)
Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Mortgage servicing assets, Fair value	$ 452	$ 452
Discount rate | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	10.25	10.25
Prepayment speed (CPR) | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	(13.54)	(12.58)
Annual cost to service (per loan, in dollars) | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	75	75
Discounted cash flow model | Fair Value, Measurements, Nonrecurring | Level 3 | Mortgage Servicing Assets
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Fair value	$ 452	$ 452
Minimum | Discount rate | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	9.25	9.25
Minimum | Prepayment speed (CPR) | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	9.36	11.09
Maximum | Discount rate | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	11.25	11.25
Maximum | Prepayment speed (CPR) | Fair Value, Measurements, Nonrecurring | Level 3
Assets Measured at Fair Value on Nonrecurring Basis and Related Losses
Servicing Asset, Measurement Input	18.16	14.24

Subsequent Events (Details)

Subsequent Events (Details) - $ / shares	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Subsequent Events
Quarterly cash dividend declared on common stock (in dollars per share)		$ 0.23	$ 0.22	$ 0.69	$ 0.76
Subsequent event
Subsequent Events
Quarterly cash dividend declared on common stock (in dollars per share)	$ 0.23