Safety Insurance (SAFT) 10-Q 8 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	May 06, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2020
Entity File Number	000-50070
Entity Registrant Name	SAFETY INSURANCE GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-4181699
Entity Address, Address Line One	20 Custom House Street
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02110
City Area Code	617
Local Phone Number	951-0600
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	SAFT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		15,309,497
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001172052
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Investments:
Fixed maturities, available for sale, at fair value (amortized cost: $1,159,859 and $1,192,357; allowance for expected credit losses of $2,510 at March 31, 2020)	$ 1,165,455	$ 1,228,040
Equity securities, at fair value (cost: $153,359 and $151,121)	149,888	177,637
Other invested assets	41,881	37,278
Total investments	1,357,224	1,442,955
Cash and cash equivalents	41,567	44,407
Accounts receivable, net of allowance for expected credit losses of $334 at March 31, 2020	189,671	193,369
Receivable for securities sold	1,067	1,784
Accrued investment income	9,152	8,404
Taxes recoverable		1,003
Receivable from reinsurers related to paid loss and loss adjustment expenses	14,039	11,319
Receivable from reinsurers related to unpaid loss and loss adjustment expenses	121,337	122,372
Ceded unearned premiums	30,191	35,182
Deferred policy acquisition costs	72,132	74,287
Deferred income taxes	6,001
Equity and deposits in pools	30,004	29,791
Operating lease right-of-use-assets	34,256	33,998
Other assets	24,078	23,798
Total assets	1,930,719	2,022,669
Liabilities
Loss and loss adjustment expense reserves	608,693	610,566
Unearned premium reserves	428,291	442,219
Accounts payable and accrued liabilities	55,911	75,016
Payable for securities purchased	4,343	6,377
Payable to reinsurers	2,446	12,911
Deferred income taxes		5,717
Taxes payable	543
Debt.	30,000
Operating lease liabilities	34,256	33,998
Other liabilities	4,127	27,459
Total liabilities	1,168,610	1,214,263
Commitments and contingencies (Note 8)
Shareholders' equity
Common stock: $0.01 par value; 30,000,000 shares authorized; 17,732,359 and 17,662,779 shares issued	177	177
Additional paid-in capital	204,064	202,321
Accumulated other comprehensive income, net of taxes	6,404	28,190
Retained earnings	645,691	661,553
Treasury stock, at cost: 2,422,862 and 2,279,570 shares	(94,227)	(83,835)
Total shareholders' equity	762,109	808,406
Total liabilities and shareholders' equity	$ 1,930,719	$ 2,022,669

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Consolidated Balance Sheets
Fixed maturity securities, amortized cost	$ 1,159,859	$ 1,192,357
Fixed maturity securities, allowance for expected credit losses	2,510
Equity securities, at cost	153,359	151,121
Allowance for expected credit losses	$ 334	$ 578
Common stock par value (in dollars per share)	$ 0.01	$ 0.01
Common stock shares authorized	30,000,000	30,000,000
Common stock shares issued	17,732,359	17,662,779
Treasury stock shares	2,422,862	2,279,570

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues
Net earned premiums	$ 197,895	$ 194,491
Net investment income	10,710	11,751
Earnings from partnership investments	1,339	835
Net realized losses on investments	(631)	(164)
Change in net unrealized gains on equity investments	(29,988)	11,801
Net impairment losses on investments (a)		(220)
Credit loss expense	(2,510)
Finance and other service income	4,229	4,085
Total revenue	181,044	222,579
Expenses
Losses and loss adjustment expenses	120,746	126,027
Underwriting, operating and related expenses	63,082	60,434
Interest expense	47	22
Total expenses	183,875	186,483
(Loss) income before income taxes	(2,831)	36,096
Income tax (benefit) expense	(841)	6,150
Net (loss) income	$ (1,990)	$ 29,946
(Loss) earnings per weighted average common share:
Basic (in dollars per share)	$ (0.13)	$ 1.97
Diluted (in dollars per share)	(0.13)	1.95
Cash dividends paid per common share (in dollars per share)	$ 0.90	$ 0.80
Number of shares used in computing earnings per share:
Basic (in shares)	15,230,784	15,140,804
Diluted (in shares)	15,347,083	15,305,785

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Consolidated Statements of Comprehensive (Loss) Income
Net (loss) income	$ (1,990)	$ 29,946
Other comprehensive (loss) income, net of tax:
Unrealized holding (losses) gains during the period, net of income tax (benefit) expense of ($5,924) and $5,296.	(22,284)	19,923
Reclassification adjustment for net realized losses on investments included in net (loss) income, net of income tax benefit of $132 and $35.	498	130
Other comprehensive (loss) income, net of tax:	(21,786)	20,053
Comprehensive (loss) income	$ (23,776)	$ 49,999

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Consolidated Statements of Comprehensive Income.
Tax (benefit) expense on unrealized holding (losses) gains during the period	$ (5,924)	$ 5,296
Tax benefit on reclassification adjustment for gains included in net income	$ 132	$ 35

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income, Net of Taxes	Retained Earnings	Treasury Stock	Total
Balance at Dec. 31, 2018	$ 176	$ 196,292	$ (10,706)	$ 616,717	$ (83,835)	$ 718,644
Net (loss) income				29,946		29,946
Unrealized gains (losses) on securities available for sale, net of deferred federal income taxes			20,053			20,053
Restricted share awards issued	1	462				463
Recognition of employee share-based compensation, net of deferred federal income taxes		1,260				1,260
Dividends paid and accrued				(12,300)		(12,300)
Balance at Mar. 31, 2019	177	198,014	9,347	631,990	(83,835)	755,693
Cumulative effect of adoption of updated accounting guidance for callable debt securities at January 1, 2019				(2,373)		(2,373)
Balance at Dec. 31, 2019	177	202,321	28,190	661,553	(83,835)	808,406
Net (loss) income				(1,990)		(1,990)
Unrealized gains (losses) on securities available for sale, net of deferred federal income taxes			(21,786)			(21,786)
Restricted share awards issued		528				528
Recognition of employee share-based compensation, net of deferred federal income taxes		1,215				1,215
Dividends paid and accrued				(13,872)		(13,872)
Acquisition of treasury stock					(10,392)	(10,392)
Balance at Mar. 31, 2020	$ 177	$ 204,064	$ 6,404	$ 645,691	$ (94,227)	$ 762,109

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net (loss) income	$ (1,990)	$ 29,946
Adjustments to reconcile net (loss) income to net cash used for operating activities:
Investment amortization, net	1,774	777
Fixed Asset depreciation, net	1,606	1,207
Stock based compensation	1,744	1,723
(Credit) Provision for deferred income taxes	(5,927)	469
Net realized losses on investments	631	164
Net impairment losses on investments		220
Credit loss expense	2,510
Earnings from partnership investments	(1,339)	(835)
Change in net unrealized gains on equity investments	29,988	(11,801)
Changes in assets and liabilities:
Accounts receivable	3,698	1,408
Accrued investment income	(748)	(1,030)
Receivable from reinsurers	(1,685)	(16,992)
Ceded unearned premiums	4,991	437
Deferred policy acquisition costs	2,155	1,450
Taxes recoverable	1,003
Other assets	877	(3,849)
Loss and loss adjustment expense reserves	(1,873)	(2,957)
Unearned premium reserves	(13,928)	(4,991)
Taxes payable	543	2,196
Accounts payable and accrued liabilities	(18,748)	(17,357)
Payable to reinsurers	(10,465)	6,719
Other liabilities	(23,332)	5,084
Net cash used for operating activities	(28,515)	(8,012)
Cash flows from investing activities:
Fixed maturities purchased	(32,329)	(31,389)
Equity securities purchased	(12,095)	(5,169)
Other invested assets purchased	(3,389)	(1,750)
Proceeds from sales and paydowns of fixed maturities	33,433	33,587
Proceeds from maturities, redemptions, and calls of fixed maturities	28,909	7,260
Proceed from sales of equity securities	8,638	4,874
Proceeds from other invested assets redeemed	106
Fixed assets purchased	(2,977)	(1,127)
Net cash provided by investing activities	20,296	6,286
Cash flows from financing activities:
Debt	30,000
Dividends paid to shareholders	(14,229)	(12,964)
Acquisition of treasury stock	(10,392)
Net cash provided by (used for) financing activities	5,379	(12,964)
Net decrease in cash and cash equivalents	(2,840)	(14,690)
Cash and cash equivalents at beginning of year	44,407	37,582
Cash and cash equivalents at end of period	$ 41,567	$ 22,892

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2020
Basis of Presentation
Basis of Presentation	1. Basis of Presentation ​ The consolidated financial statements have been prepared on the basis of accounting principles generally accepted in the United States of America (“GAAP”). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from these estimates. ​ The consolidated financial statements include Safety Insurance Group, Inc. and its subsidiaries (the “Company”). The subsidiaries consist of Safety Insurance Company, Safety Indemnity Insurance Company, Safety Property and Casualty Insurance Company, Safety Asset Management Corporation (“SAMC”), and Safety Management Corporation, which is SAMC’s holding company. All intercompany transactions have been eliminated. ​ The financial information for the three months ended March 31, 2020 and 2019 is unaudited; however, in the opinion of the Company, the information includes all adjustments, consisting only of normal recurring adjustments, necessary for a fair presentation of the financial condition, results of operations, and cash flows for the periods. The financial information as of December 31, 2019 is derived from the audited financial statements included in the Company's 2019 Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (“SEC”) on February 28, 2020. ​ These unaudited interim consolidated financial statements may not be indicative of financial results for the full year and should be read in conjunction with the audited financial statements included in the Company’s 2019 Annual Report on Form 10-K filed with the SEC on February 28, 2020. ​ The Company is a leading provider of property and casualty insurance focused primarily on the Massachusetts market. The Company’s principal product line is automobile insurance. The Company operates through its insurance company subsidiaries, Safety Insurance Company, Safety Indemnity Insurance Company, and Safety Property and Casualty Insurance Company (together referred to as the “Insurance Subsidiaries”). ​ ​ Management has assessed and concluded that there were no conditions or events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the financial statements were issued. ​

Recent Accounting Pronouncement

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2020
Recent Accounting Pronouncements
Recent Accounting Pronouncements	2. Recent Accounting Pronouncements ​ On March 20, 2019, the SEC adopted amendments to Regulation S-K and related rules and forms to modernize and simplify certain disclosure requirements for public companies. The amendments are intended to reduce the costs and burdens of the disclosure process while continuing to require disclosure of all material information. The amended rules generally were effective on May 2, 2019 and reduce disclosures but some provisions added new requirements. The adoption of the new rules did not have a material impact on the Company’s financial position, results of operations, cash flows, or disclosures. ​ In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement measurement disclosure requirements under ASC 820. The Company’s adoption of ASU 2018-13 on January 1, 2020 did not have an impact on the fair value disclosures included in Note 5 – Investments. In March 2017, the FASB issued ASU 2017-08, Receivables – Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Statements ​ In February 2016, the FASB issued ASU 2016-02, Leases Codification Improvements to Topic 842, Leases Leases (Topic 842): Targeted Improvements, creates an additional transition method which allows companies to elect to not adjust their comparative period financial information and disclosures for the effects of the new lease standard and also creates a practical expedient for lessors to not separate lease and non-lease components. The Company adopted ASU 2016-02, ASU 2018-10 and ASU 2018-11 effective January 1, 2019 (“the application date”) using the required modified retrospective transition approach. In accordance with the guidance, the Company has elected not to adjust comparative periods. As such, Accounting Standards Codification (“ASC”) 842 will be applied to each lease that had commenced as of the application date with a cumulative effect adjustment as of that date. As of January 1, 2019, a right of use asset and lease liability of $35,984 were recorded in the Consolidated Balance Sheets. There was no impact on retained earnings or other components of equity in the Consolidated Balance Sheets as of March 31, 2020 and December 31, 2019. ​ ​

Earnings per Weighted Average C

Earnings per Weighted Average Common Share	3 Months Ended
	Mar. 31, 2020
Earnings per Weighted Average Common Share
Earnings per Weighted Average Common Share	3. Earnings per Weighted Average Common Share ​ Basic earnings per weighted average common share (“EPS”) are calculated by dividing net income by the weighted average number of basic common shares outstanding during the period. Diluted earnings per share amounts are based on the weighted average number of common shares including non-vested performance stock grants. ​ The following table sets forth the computation of basic and diluted EPS for the periods indicated. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2020 ​ 2019 ​ (Loss) Earnings attributable to common shareholders - basic and diluted: ​ ​ ​ ​ ​ ​ ​ Net (loss) income from continuing operations ​ $ (1,990) ​ $ 29,946 ​ Allocation of loss (income) for participating shares ​ ​ 10 ​ ​ (167) ​ Net (loss) income from continuing operations attributed to common shareholders ​ $ (1,980) ​ $ 29,779 ​ (Loss) Earnings per share denominator - basic and diluted ​ ​ ​ ​ ​ ​ ​ Total weighted average common shares outstanding, including participating shares ​ ​ 15,304,758 ​ ​ 15,225,774 ​ Less: weighted average participating shares ​ ​ (73,974) ​ ​ (84,970) ​ Basic (loss) earnings per share denominator ​ ​ 15,230,784 ​ ​ 15,140,804 ​ Common equivalent shares- non-vested performance stock grants ​ 116,299 ​ 164,981 ​ Diluted (loss) earnings per share denominator ​ 15,347,083 ​ 15,305,785 ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic (loss) earnings per share ​ $ (0.13) ​ $ 1.97 ​ Diluted (loss) earnings per share ​ $ (0.13) ​ $ 1.95 ​ ​ ​ ​ ​ ​ ​ ​ ​ Undistributed (loss) earnings attributable to common shareholders - basic and diluted: ​ ​ ​ ​ ​ ​ ​ Net (loss) income from continuing operations attributable to common shareholders -Basic ​ $ (0.13) ​ $ 1.97 ​ Dividends declared ​ ​ (0.90) ​ ​ (0.80) ​ Undistributed (loss) earnings ​ $ (1.03) ​ $ 1.17 ​ ​ ​ ​ ​ ​ ​ ​ ​ Net (loss) income from continuing operations attributable to common shareholders -Diluted ​ $ (0.13) ​ $ 1.95 ​ Dividends declared ​ ​ (0.90) ​ ​ (0.80) ​ Undistributed (loss) earnings ​ $ (1.03) ​ $ 1.15 ​ ​ ​

Share-Based Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2020
Share-Based Compensation
Share-Based Compensation	4. Share-Based Compensation ​ 2018 Long Term Incentive Plan ​ On April 2, 2018, the Company’s Board of Directors adopted the Safety Insurance Group, Inc. 2018 Long-Term Incentive Plan (“the 2018 Plan”), which was subsequently approved by our shareholders at the 2018 Annual Meeting of Shareholders. The 2018 Plan enables the grant of stock awards, performance shares, cash-based performance units, other stock-based awards, stock options, stock appreciation rights, and stock unit awards, each of which may be granted separately or in tandem with other awards. Eligibility to participate includes officers, directors, employees and other individuals who provide bona fide services to the Company. The 2018 Plan supersedes the Company’s 2002 Management Omnibus Incentive Plan (“the 2002 Incentive Plan”). ​ The 2018 Plan establishes an initial pool of 350,000 shares of common stock available for issuance to our employees and other eligible participants. The maximum number of shares of common stock between both the 2018 Plan and 2002 Incentive Plan with respect to which awards may be granted is 2,850,000. No further grants will be allowed under the 2002 Incentive Plan. At March 31, 2020, there were 234,170 shares available for future grant. ​ Accounting and Reporting for Stock-Based Awards ​ Accounting Standards Codification (“ASC”) 718, Compensation —Stock Compensation requires the Company to measure and recognize the cost of employee services received in exchange for an award of equity instruments. Under the provisions of ASC 718, share-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized as an expense over the requisite service period (generally the vesting period of the equity grant). ​ Restricted Stock ​ Service-based restricted stock awarded in the form of unvested shares is recorded at the market value of the Company’s common stock on the grant date and amortized ratably as compensation expense over the requisite service period. Service-based restricted stock awards generally vest over a three-year period and vest 30% on the first and second anniversaries of the grant date and 40% on the third anniversary of the grant date, except for non-executive employees’ restricted stock awards granted prior to 2018 which vest ratably over a five-year service period and independent directors’ stock awards which vest immediately. Our independent directors are subject to stock ownership guidelines, which require them to have a value four times their annual cash retainer. ​ In addition to service-based awards, the Company grants performance-based restricted shares to certain employees. These performance shares cliff vest after a three-year performance period provided certain performance measures are attained. A portion of these awards, which contain a market condition, vest according to the level of total shareholder return achieved by the Company compared to its property-casualty insurance peers over a three-year period. The remainder, which contain a performance condition, vest according to the level of Company’s combined ratio results compared to a target based on its property-casualty insurance peers. ​ Actual payouts can range from 0% to 200% of target shares awarded depending upon the level of achievement of the respective market and performance conditions during a three calendar-year performance period. Compensation expense for share awards with a performance condition is based on the probable number of awards expected to vest using the performance level most likely to be achieved at the end of the performance period. ​ Performance-based awards with market conditions are accounted for and measured differently from awards that have a performance or service condition. The effect of a market condition is reflected in the award’s fair value on the grant date. That fair value is recognized as compensation cost over the requisite service period regardless of whether the market-based performance objective has been satisfied. ​ All of the Company’s restricted stock awards are issued as incentive compensation and are equity classified. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes restricted stock activity under the Incentive Plan during the three months ended March 31, 2020 assuming a target payout for the 2020 performance-based shares. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shares Weighted ​ Performance-based Weighted ​ ​ Under ​ Average ​ Shares Under ​ Average ​ ​ Restriction ​ Fair Value ​ Restriction ​ Fair Value Outstanding at beginning of year 78,202 ​ $ 79.09 ​ 84,105 ​ $ 79.34 Granted 34,799 ​ ​ 90.10 ​ 36,649 (1) ​ 84.68 Vested and unrestricted (43,480) ​ ​ 78.07 ​ (42,123) ​ ​ 73.55 Forfeited ​ — ​ ​ — ​ (1,868) ​ ​ 84.61 Outstanding at end of period 69,521 ​ $ 85.24 ​ 76,763 ​ $ 84.94 (1) Includes a true-up of previously awarded performance-based restricted share awards. The updated shares were calculated based on the attainment of pre-established performance objectives and granted under the 2002 Incentive Plan. ​

Investments

Investments	3 Months Ended
	Mar. 31, 2020
Investments
Investments	5. Investments ​ The gross unrealized gains and losses on investments in fixed maturity securities, including redeemable preferred stocks that have characteristics of fixed maturities, and equity securities, including interests in mutual funds, and other invested assets were as follows for the periods indicated. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost or Allowance for Gross Unrealized Estimated ​ ​ Amortized ​ Expected Credit ​ ​ ​ ​ ​ Fair ​ ​ Cost ​ Losses ​ Gains ​ Losses (3) ​ Value U.S. Treasury securities ​ $ 1,823 ​ $ — ​ $ 60 ​ $ — ​ $ 1,883 Obligations of states and political subdivisions ​ 224,800 ​ — ​ 8,924 ​ (34) ​ 233,690 Residential mortgage-backed securities (1) ​ 288,122 ​ — ​ 12,998 ​ (103) ​ 301,017 Commercial mortgage-backed securities ​ 105,678 ​ — ​ 3,553 ​ (165) ​ 109,066 Other asset-backed securities ​ 26,659 ​ — ​ 63 ​ (1,415) ​ 25,307 Corporate and other securities ​ 512,777 ​ (2,510) ​ 9,127 ​ (24,902) ​ 494,492 Subtotal, fixed maturity securities ​ 1,159,859 ​ (2,510) ​ 34,725 ​ (26,619) ​ 1,165,455 Equity securities (2) ​ 153,359 ​ — ​ 13,874 ​ (17,345) ​ 149,888 Other invested assets (4) ​ 41,881 ​ — ​ — ​ — ​ 41,881 Totals ​ $ 1,355,099 ​ $ (2,510) ​ $ 48,599 ​ $ (43,964) ​ $ 1,357,224 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost or Gross Unrealized Estimated ​ ​ Amortized ​ ​ ​ ​ ​ Fair ​ ​ Cost ​ Gains ​ Losses ​ Value U.S. Treasury securities ​ $ 1,504 ​ $ 8 ​ $ — ​ $ 1,512 ​ Obligations of states and political subdivisions ​ 241,597 ​ 9,799 ​ — ​ 251,396 ​ Residential mortgage-backed securities (1) ​ 301,503 ​ 6,608 ​ (909) ​ 307,202 ​ Commercial mortgage-backed securities ​ 106,902 ​ 3,233 ​ (397) ​ 109,738 ​ Other asset-backed securities ​ 36,068 ​ 218 ​ (64) ​ 36,222 ​ Corporate and other securities ​ 504,783 ​ 18,455 ​ (1,268) ​ 521,970 ​ Subtotal, fixed maturity securities ​ 1,192,357 ​ 38,321 ​ (2,638) ​ 1,228,040 ​ Equity securities (2) ​ 151,121 ​ 27,879 ​ (1,363) ​ 177,637 ​ Other invested assets (4) ​ 37,278 ​ — ​ — ​ 37,278 ​ Totals ​ $ 1,380,756 ​ $ 66,200 ​ $ (4,001) ​ $ 1,442,955 ​ (1) Residential mortgage-backed securities consists primarily of obligations of U.S. Government agencies including collateralized mortgage obligations issued, guaranteed and/or insured by the following issuers: Government National Mortgage Association (GNMA), Federal Home Loan Mortgage Corporation (FHLMC), Federal National Mortgage Association (FNMA) and the Federal Home Loan Bank (FHLB). (2) Equity securities include common stock, preferred stock, mutual funds and interests in mutual funds held to fund the Company’s executive deferred compensation plan. (3) The Company’s investment portfolio included 733 and 229 securities in an unrealized loss position at March 31, 2020 and December 31, 2019, respectively. (4) Other invested assets are accounted for under the equity method which approximated fair value. ​ The amortized cost and the estimated fair value of fixed maturity securities, by maturity, are shown below for the period indicated. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ Amortized Estimated ​ ​ Cost ​ Fair Value Due in one year or less ​ $ 51,519 ​ $ 51,881 Due after one year through five years ​ 295,621 ​ 287,963 Due after five years through ten years ​ 311,755 ​ 305,990 Due after ten years through twenty years ​ 79,555 ​ 83,326 Due after twenty years ​ 950 ​ 906 Asset-backed securities ​ 420,459 ​ 435,389 Totals ​ $ 1,159,859 ​ $ 1,165,455 ​ The gross realized losses and gains on sales of investments were as follows for the periods indicated. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 Gross realized gains ​ ​ ​ ​ ​ ​ ​ Fixed maturity securities ​ $ 889 ​ $ 115 ​ Equity securities ​ 1,576 ​ 953 ​ Gross realized losses ​ ​ ​ ​ ​ ​ ​ Fixed maturity securities ​ (301) ​ (667) ​ Equity securities ​ (2,795) ​ (565) ​ Net realized losses on investments ​ $ (631) ​ $ (164) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ In the normal course of business, the Company enters into transactions involving various types of financial instruments, including investments in fixed maturities and equity securities. Investment transactions have credit exposure to the extent that a counter party may default on an obligation to the Company. Credit risk is a consequence of carrying, trading and investing in securities. To manage credit risk, the Company focuses on higher quality fixed income securities, reviews the credit strength of all companies in which it invests, limits its exposure in any one investment and monitors the portfolio quality, taking into account credit ratings assigned by recognized statistical rating organizations. ​ The following tables as of March 31, 2020 and December 31, 2019 present the gross unrealized losses included in the Company’s investment portfolio and the fair value of those securities aggregated by investment category. The tables also present the length of time that they have been in a continuous unrealized loss position. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ ​ Less than 12 Months ​ 12 Months or More ​ Total ​ Estimated Unrealized Estimated Unrealized Estimated Unrealized ​ ​ Fair Value ​ Losses ​ Fair Value ​ Losses ​ Fair Value ​ Losses U.S. Treasury securities ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — Obligations of states and political subdivisions ​ 656 ​ 34 ​ — ​ — ​ 656 ​ 34 Residential mortgage-backed securities ​ 20,492 ​ 99 ​ 195 ​ 4 ​ 20,687 ​ 103 Commercial mortgage-backed securities ​ 22,272 ​ 165 ​ — ​ — ​ 22,272 ​ 165 Other asset-backed securities ​ 14,840 ​ ​ 534 ​ ​ 8,202 ​ ​ 881 ​ ​ 23,042 ​ ​ 1,415 Corporate and other securities ​ 233,543 ​ 23,185 ​ 8,758 ​ 1,717 ​ 242,301 ​ 24,902 Subtotal, fixed maturity securities ​ 291,803 ​ 24,017 ​ 17,155 ​ 2,602 ​ 308,958 ​ 26,619 Equity securities ​ 67,644 ​ 13,991 ​ 9,909 ​ 3,354 ​ 77,553 ​ 17,345 Total temporarily impaired securities ​ $ 359,447 ​ $ 38,008 ​ $ 27,064 ​ $ 5,956 ​ $ 386,511 ​ $ 43,964 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2019 ​ ​ Less than 12 Months ​ 12 Months or More ​ Total ​ Estimated Unrealized Estimated Unrealized Estimated Unrealized ​ ​ Fair Value ​ Losses ​ Fair Value ​ Losses ​ Fair Value ​ Losses U.S. Treasury securities ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — Obligations of states and political subdivisions ​ — ​ — ​ — ​ — ​ — ​ — Residential mortgage-backed securities ​ 61,933 ​ 409 ​ 31,655 ​ 500 ​ 93,588 ​ 909 Commercial mortgage-backed securities ​ 36,398 ​ 397 ​ 866 ​ — ​ 37,264 ​ 397 Other asset-backed securities ​ 21,281 ​ ​ 64 ​ ​ 462 ​ ​ — ​ 21,743 ​ 64 Corporate and other securities ​ 26,386 ​ 481 ​ 13,718 ​ 787 ​ 40,104 ​ 1,268 Subtotal, fixed maturity securities ​ 145,998 ​ 1,351 ​ 46,701 ​ 1,287 ​ 192,699 ​ 2,638 Equity securities ​ 8,849 ​ 391 ​ 14,143 ​ 972 ​ 22,992 ​ 1,363 Total temporarily impaired securities ​ $ 154,847 ​ $ 1,742 ​ $ 60,844 ​ $ 2,259 ​ $ 215,691 ​ $ 4,001 ​ Impairments ​ Beginning January 1, 2020, ASC 326, Credit Losses: Measurement of Credit Losses on Financial Instruments changed the process by which AFS debt securities are evaluated for impairment, requiring as the standard requires a new impairment model based on expected credit losses rather than incurred credit losses. Under the new guidance, an entity recognizes its estimate of expected credit losses through an allowance account. ​ For fixed maturities that the Company does not intend to sell or for which it is more likely than not that the Company would not be required to sell before an anticipated recovery in value, the Company separates the credit loss component of the impairment from the amount related to all other factors and reports the credit loss component as credit loss expense. The impairment related to all other factors (non-credit factors) is reported in other comprehensive income. The allowance is adjusted for any additional credit losses and subsequent recoveries. Upon recognizing a credit loss, the cost basis is not adjusted. ​ For fixed maturities where the Company records a credit loss, a determination is made as to the cause of the impairment and whether the Company expects a recovery in the value. For fixed maturities where the Company expects a recovery in value, the constant effective yield method is utilized, and the investment is amortized to par. ​ For fixed maturity investments the Company intends to sell or for which it is more likely than not that the Company will be required to sell before an anticipated recovery in value, the full amount of the impairment is included in credit loss expense. The new cost basis of the investment is the previous amortized cost basis less the impairment recognized in credit loss expense. The new cost basis is not adjusted for any subsequent recoveries in fair value. ​ The Company uses a systematic methodology to evaluate declines in fair values below cost or amortized cost of our investments. Some of the factors considered in assessing impairment of fixed maturities due to credit losses include the extent to which the fair value is less than amortized cost, the financial condition of and the near and long-term prospects of the issuer, whether the debtor is current on its contractually obligated interest and principal payments, changes to the rating of the security by a rating agency, the historical volatility of the fair value of the security and whether it is more like than not that the Company will be required to sell the investment prior to an anticipated recovery in value. ​ The Company’s analysis of its fixed maturity portfolio at March 31, 2020 concluded that $2,510 of unrealized losses were due to credit factors and were recorded as credit loss expense for the three months ended March 31, 2020. The Company concluded that outside of the securities that were recognized as credit impaired, the unrealized losses recorded on the fixed maturity portfolio at March 31, 2020 resulted from fluctuations in market interest rates and other temporary market conditions as opposed to fundamental changes in the credit quality of the issuers of such securities. Based upon the analysis performed, the Company’s decision to hold these securities, the Company’s current level of liquidity and our history of positive operating cash flows, management believes it is more likely than not that it will not be required to sell any of its securities before the anticipated recovery in the fair value to its amortized cost basis. ​ During the three months ended March 31, 2019, the company recognized $220 in other-than-temporary impairments under the previous accounting guidance in ASC 320, Investments – Debt and Equity Securities ​ The Company holds no subprime mortgage debt securities. All of the Company’s holdings in mortgage-backed securities are either U.S. Government or Agency guaranteed or are rated investment grade by either Moody’s or Standard & Poor’s. ​ The following table represents a reconciliation of the beginning and ending balances of the allowance for expected credit losses on fixed maturities classified as available for sale. ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2020 ​ ​ ​ ​ ​ ​ Corporate and other ​ ​ securities Balance January 1, 2020 ​ $ — Credit losses on securities with no previously recorded credit losses ​ 2,510 Net increases (decreases) in allowance on previously impaired securities ​ — Reduction due to sales ​ — Writeoffs charged against allowance ​ — Recoveries of amounts previously written off ​ — Balance March 31, 2020 ​ $ 2,510 ​ ​ ​ ​ ​ ​ ​ ​ ​ Net Investment Income ​ The components of net investment income were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 Interest on fixed maturity securities ​ $ 9,759 ​ $ 11,127 ​ Dividends on equity securities ​ 1,206 ​ 1,082 ​ Equity in earnings of other invested assets ​ 516 ​ 282 ​ Interest on other assets ​ 7 ​ 9 ​ Total investment income ​ 11,488 ​ 12,500 ​ Investment expenses ​ 778 ​ 749 ​ Net investment income ​ $ 10,710 ​ $ 11,751 ​ ​ ​ ​ Fair Value of Financial Instruments ​ ASC 820, Fair Value Measurements and Disclosure ​ Level 1 — Valuations based on quoted prices in active markets for identical assets and liabilities; ​ Level 2 — Valuations based on observable inputs that do not meet the criteria for Level 1, including quoted prices in inactive markets and quoted prices in active markets for similar, but not identical instruments; and ​ Level 3 — Valuations based on unobservable inputs. ​ Fair values for the Company’s fixed maturity securities are based on prices provided by its custodian bank and its investment managers. Both the Company’s custodian bank and investment managers use a variety of independent, nationally recognized pricing services to determine market valuations. If the pricing service cannot provide fair value determinations, the Company obtains non-binding price quotes from broker-dealers. A minimum of two quoted prices is obtained for the majority of the Company’s available-for-sale fixed maturity securities in its investment portfolio. The Company uses a third-party pricing service as its primary provider of quoted prices from third-party pricing services and broker-dealers. To provide reasonable assurance of the validity of each price or quote, a secondary third-party pricing service or broker-dealer quote is obtained from the Company’s custodian or investment managers. An examination of the pricing data is then performed for each security. If the variance between the primary and secondary price quotes for a security is within an accepted tolerance level, the quoted price obtained from the Company’s primary source is used for the security. If the variance between the primary and secondary price quotes exceeds an accepted tolerance level, the Company obtains a quote from an alternative source, if possible, and documents and resolves any differences between the pricing sources. In addition, the Company may request that its investment managers and its traders provide input as to which vendor is providing prices that its traders believe are reflective of fair value for the security. Following this process, the Company may decide to value the security in its financial statements using the secondary or alternative source if it believes that pricing is more reflective of the security’s value than the primary pricing provided by its custodian bank. The Company analyzes market valuations received to verify reasonableness, to understand the key assumptions used and their sources, and to determine an appropriate ASC 820 fair value hierarchy level based upon trading activity and the observability of market inputs. Based on this evaluation and investment class analysis, each price is classified into Level 1, 2 or 3. ​ Fair values of instruments are based on (i) quoted prices in active markets for identical assets (Level 1), (ii) quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-derived valuations in which all significant inputs are observable in active markets (Level 2) or (iii) valuations derived from valuation techniques in which one or more significant inputs are unobservable in the marketplace (Level 3). ​ The Company’s Level 1 securities consist of equity securities whose values are based on quoted prices in active markets for identical assets. The Company’s Level 2 securities are comprised of available-for-sale fixed maturity securities whose fair value was determined using observable market inputs. The Company’s Level 3 security consists of an investment in the Federal Home Loan Bank of Boston related to Safety Insurance Company’s membership stock, which is not redeemable in a short-term time frame. Fair values for securities for which quoted market prices were unavailable were estimated based upon reference to observable inputs such as benchmark interest rates, market comparables, and other relevant inputs. Investments valued using these inputs include U.S. Treasury securities, obligations of states and political subdivisions, corporate and other securities, commercial and residential mortgage-backed securities, and other asset-backed securities. Inputs into the fair value application that are utilized by asset class include but are not limited to: ​ ● Obligations of states and political subdivisions ​ ● Corporate and other securities ​ ● Residential mortgage-backed securities U.S. agency pass-throughs, collateralized mortgage obligations (“CMOs”), non U.S. agency CMOs ​ ● Commercial mortgage-backed securities ​ ● Other asset-backed securities ​ ● Federal Home Loan Bank of Boston ​ In order to ensure the fair value determination is representative of an exit price (consistent with ASC 820), the Company’s procedures for validating quotes or prices obtained from third parties include, but are not limited to, obtaining a minimum of two price quotes for each fixed maturity security if possible, as discussed above, the periodic testing of sales activity to determine if there are any significant differences between the market price used to value the security as of the balance sheet date and the sales price of the security for sales that occurred around the balance sheet date, and the periodic review of reports provided by its external investment manager regarding those securities with ratings changes and securities placed on its “Watch List.” In addition, valuation techniques utilized by pricing services and prices obtained from external sources are reviewed by the Company’s external investment manager, whose investment professionals are familiar with the securities being priced and the markets in which they trade, to ensure the fair value determination is representative of an exit price (consistent with ASC 820). ​ All unadjusted estimates of fair value for our fixed maturities priced by the pricing services as described above are included in the amounts disclosed in Level 2. With the exception of the FHLB-Boston security, which is categorized as a Level 3 security, the Company’s entire portfolio was priced based upon quoted market prices or other observable inputs as of March 31, 2020. There were no significant changes to the valuation process during the three months ended March 31, 2020. As of March 31, 2020 and December 31, 2019, no quotes or prices obtained were adjusted by management. All broker quotes obtained were non-binding. ​ At March 31, 2020 and December 31, 2019, investments in fixed maturities classified as available-for-sale had a fair value which equaled carrying value $1,165,455 and $1,228,040 , respectively. We have no short-term investments. The carrying values of cash and cash equivalents and investment income accrued approximated fair value. ​ The following tables summarize the Company’s total fair value measurements for investments for the periods indicated. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ Total Level 1 Inputs Level 2 Inputs Level 3 Inputs U.S. Treasury securities ​ $ 1,883 ​ $ — ​ $ 1,883 ​ $ — Obligations of states and political subdivisions ​ 233,690 ​ — ​ 233,690 ​ — Residential mortgage-backed securities ​ 301,017 ​ — ​ 301,017 ​ — Commercial mortgage-backed securities ​ 109,066 ​ — ​ 109,066 ​ — Other asset-backed securities ​ 25,307 ​ — ​ 25,307 ​ — Corporate and other securities ​ 494,492 ​ — ​ 494,492 ​ — Equity securities ​ 117,082 ​ 115,396 ​ — ​ 1,686 Total investment securities ​ $ 1,282,537 ​ $ 115,396 ​ $ 1,165,455 ​ $ 1,686 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2019 ​ Total Level 1 Inputs Level 2 Inputs Level 3 Inputs U.S. Treasury securities ​ $ 1,512 ​ $ — ​ $ 1,512 ​ $ — Obligations of states and political subdivisions ​ 251,396 ​ — ​ 251,396 ​ — Residential mortgage-backed securities ​ 307,202 ​ — ​ 307,202 ​ — Commercial mortgage-backed securities ​ 109,738 ​ — ​ 109,738 ​ — Other asset-backed securities ​ 36,222 ​ — ​ 36,222 ​ — Corporate and other securities ​ 521,970 ​ — ​ 521,970 ​ — Equity securities ​ 144,877 ​ 144,361 ​ — ​ 516 Total investment securities ​ $ 1,372,917 ​ $ 144,361 ​ $ 1,228,040 ​ $ 516 ​ There were no transfers between Level 1 and Level 2 during the three months ended March 31, 2020 and 2019. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The following table summarizes the changes in the Company’s Level 3 fair value securities for the periods indicated. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 ​ ​ Level 3 ​ Level 3 ​ ​ Fair Value ​ Fair Value ​ ​ Securities ​ Securities Balance at beginning of period ​ $ 516 ​ $ 680 ​ Net gains and losses included in earnings ​ — ​ — ​ Net gains included in other comprehensive income ​ — ​ — ​ Purchases ​ 1,170 ​ — ​ Sales ​ ​ — ​ ​ (297) ​ Transfers into Level 3 ​ ​ — ​ — ​ Transfers out of Level 3 ​ — ​ — ​ Balance at end of period ​ $ 1,686 ​ $ 383 ​ Amount of total losses included in earnings attributable to the change in unrealized losses related to assets still held at end of period ​ $ — ​ $ — ​ ​ Transfers in and out of Level 3 are attributable to changes in the ability to observe significant inputs in determining fair value exit pricing. As noted in the table above, no transfers were made in or out of Level 3 during the three months ended March 31, 2020 and 2019. The Company held one Level 3 security at March 31, 2020 and March 31, 2019. ​ , respectively, in a real estate investment trust (“REIT”). The REIT is excluded from the fair value hierarchy because the fair value is recorded using the net asset value per share practical expedient. The net asset value per share of this REIT is derived from member ownership in the capital venture to which a proportionate share of independently appraised net assets is attributed. The fair value was determined using the trust’s net asset value obtained from its audited financial statements. The Company is required to submit a request 45 days before a quarter end to dispose of the security. ​

Allowance for Expected Credit L

Allowance for Expected Credit Losses	3 Months Ended
	Mar. 31, 2020
Allowance for Expected Credit Losses
Allowance for Expected Credit Losses	6. Allowance for Expected Credit Losses ​ Beginning on January 1, 2020, credit losses are recognized through an allowance account. See Note 2 – Recent Accounting Pronouncements for additional information and Note 5 – Investments for information about the allowance for expected credit losses on AFS debt securities. ​ The Company’s financial instruments measured at amortized cost include premiums and accounts receivable, and reinsurance recoverables. ​ Premiums and accounts receivable are reported net of an allowance for expected credit losses. The allowance is based upon the Company’s ongoing review of amounts outstanding, historical loss data, including delinquencies and write-offs, current and forecasted economic conditions and other relevant factors. Credit risk is partially mitigated by the Company’s ability to cancel the policy if the policyholder does not pay the premium and the Company writes off premiums receivable balances that are more than 90 days overdue. ​ The following table presents the balances of premiums receivable, net of the allowance for expected credit losses, at March 31, 2020 and January 1, 2020, and changes in the allowance for expected credit losses for the three months ended March 31, 2020. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accounts Receivable Net of Allowance for Expected Credit Losses ​ ​ Allowance for Expected Credit Losses Balance January 1, 2020 ​ $ 193,369 ​ $ 578 Current period change for expected credit losses ​ ​ ​ 1,576 Writeoffs of uncollectable accounts receivable ​ ​ ​ (1,820) Balance March 31, 2020 ​ $ 189,671 ​ $ 334 ​ ​ Reinsurance recoverables include amounts due from reinsurers for both paid and unpaid losses. The Company cedes insurance to Commonwealth Automobile Reinsurers (“CAR”) and to other reinsurers. The Company has a property catastrophe excess of loss agreement and a casualty excess of loss agreement that qualify as reinsurance treaties and are designed to protect against large or unusual loss and LAE activity. Reinsurance contracts do not relieve the Company from its obligations to policyholders. Failure of reinsurers to honor their obligations could result in losses to the Company. The Company evaluates the financial condition of its reinsurers and monitors economic characteristics of the reinsurers to minimize its exposure to significant losses from reinsurer insolvencies. The Company reports its reinsurance recoverbales net of an allowance for estimated uncollectable reinsurance. A probability-of-default methodology which reflects current and forecasted economic conditions is used to estimate the amount of uncollectible reinsurance due to credit-related factors and the estimate is reported in an allowance for estimated uncollectible reinsurance. Amounts deemed to be uncollectible, including amounts due from known insolvent reinsurers, are written off against the allowance. Changes in the allowance, as well as any subsequent collections of amounts previously written off, are reported as part of claims and claim adjustment expenses. ​ The majority of the Company’s reinsurance recoverable on paid and unpaid losses is a result of our participation as a servicing carrier in the CAR Commercial Automobile Program and the Taxi/Limo Program, which represents 97% of the total reinsurance recoverable on paid and unpaid losses at March 31, 2020. The remaining 3% of amounts due from reinsurers are related to our other excess of loss and quota share contracts. For amounts due under these contracts, the Company utilizes updated A.M. Best credit ratings on a quarterly basis to determine the allowance for expected credit losses. As of March 31, 2020, all reinsurers under these programs are rated “A” or better by A.M. Best. Certain of the Company's reinsurance recoverables are collateralized by letters of credit, funds held or trust agreements. The Company’s analysis concludes that ​ ​

Loss and Loss Adjustment Expens

Loss and Loss Adjustment Expense Reserves	3 Months Ended
	Mar. 31, 2020
Loss and Loss Adjustment Expense Reserves
Loss and Loss Adjustment Expense Reserves	7. Loss and Loss Adjustment Expense Reserves ​ The following table sets forth a reconciliation of beginning and ending reserves for losses and loss adjustment expenses (“LAE”), as shown in the Company’s consolidated financial statements for the periods indicated. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 Reserves for losses and LAE at beginning of year ​ $ 610,566 ​ $ 584,719 Less receivable from reinsurers related to unpaid losses and LAE ​ (122,372) ​ (108,398) Net reserves for losses and LAE at beginning of year ​ 488,194 ​ 476,321 Incurred losses and LAE, related to: ​ ​ ​ ​ ​ ​ Current year ​ 130,330 ​ 138,007 Prior years ​ (9,584) ​ (11,980) Total incurred losses and LAE ​ 120,746 ​ 126,027 Paid losses and LAE related to: ​ ​ ​ ​ ​ ​ Current year ​ 48,745 ​ 58,796 Prior years ​ 72,839 ​ 70,990 Total paid losses and LAE ​ 121,584 ​ 129,786 Net reserves for losses and LAE at end of period ​ 487,356 ​ 472,562 Plus receivable from reinsurers related to unpaid losses and LAE ​ 121,337 ​ 109,200 Reserves for losses and LAE at end of period ​ $ 608,693 ​ $ 581,762 ​ At the end of each period, the reserves were re-estimated for all prior accident years. The Company’s prior year reserves decreased by $9,584 and $11,980 for the three months ended March 31, 2020 and 2019, respectively, and resulted from re-estimations of prior years ultimate loss and LAE liabilities. The decreases in prior years reserves during the three months ended March 31, 2020 and 2019 are primarily composed of reductions in our retained automobile and retained homeowners lines reserves. ​ The Company's automobile lines of business reserves decreased for the three months ended March 31, 2020 and 2019, primarily due to fewer incurred but not yet reported claims than previously estimated and better than previously estimated severity on the Company’s established bodily injury and property damage case reserves. Due to the nature of the risks that the Company underwrites and has historically underwritten, management does not believe that it has an exposure to asbestos or environmental pollution liabilities.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2020
Commitments and Contingencies
Commitments and Contingencies	​ 8. Commitments and Contingencies ​ Various claims, generally incidental to the conduct of normal business, are pending or alleged against the Company from time to time. In the opinion of management, based in part on the advice of legal counsel, the ultimate resolution of such claims will not have a material adverse effect on the Company’s consolidated financial statements. However, if estimates of the ultimate resolutions of those proceedings are revised, liabilities related to those proceedings could be adjusted in the near term. Massachusetts law requires that insurers licensed to do business in Massachusetts participate in the Massachusetts Insurers Insolvency Fund (“Insolvency Fund”). Members of the Insolvency Fund are assessed a proportionate share of the obligations and expenses of the Insolvency Fund in connection with an insolvent insurer. It is anticipated that there will be additional assessments from time to time relating to various insolvencies. Although the timing and amounts of any future assessments are not known, based upon existing knowledge, management’s opinion is that such future assessments are not expected to have a material effect upon the financial position of the Company.

Debt

Debt	3 Months Ended
	Mar. 31, 2020
Debt
Debt	9. Debt ​ On the August 10, 2018, the Company extended its Revolving Credit Agreement (the “Credit Agreement”) with Citizens Bank, N.A. (formerly known as RBS Citizens, N.A. (“Citizens Bank”)) to a maturity date of August 10, 2023. The Credit Agreement provides a $30,000 revolving credit facility with an accordion feature allowing for future expansion of the committed amount up to $50,000 . Loans under the credit facility bear interest at the Company’s option at either (i) the LIBOR rate plus 1.25% per annum or (ii) the higher of Citizens Bank prime rate or 0.5% above the federal funds rate plus 1.25% per annum. Interest only is payable prior to maturity. ​ The Company’s obligations under the credit facility are secured by pledges of its assets and the capital stock of its operating subsidiaries. The credit facility is guaranteed by the Company’s non-insurance company subsidiaries. The credit facility contains covenants including requirements to maintain minimum risk-based capital ratios and statutory surplus of Safety Insurance Company as well as limitations or restrictions on indebtedness, liens, and other matters. As of March 31, 2020, the Company was in compliance with all covenants. In addition, the credit facility includes customary events of default, including a cross-default provision permitting the lenders to accelerate the facility if the Company (i) defaults in any payment obligation under debt having a principal amount in excess of $10,000 or (ii) fails to perform any other covenant permitting acceleration of all such debt. ​ The Company had no amounts outstanding on its credit facility at March 31, 2020 and December 31, 2019. The credit facility commitment fee included in interest expense was computed at a rate of 0.25% per annum on the $30,000 commitment at March 31, 2020 and 2019. ​ using eligible invested assets that would be used as collateral. ​ ​

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2020
Income Taxes
Income Taxes	10. Income Taxes ​ Federal income tax expense for the three months ended March 31, 2020 and 2019 has been computed using estimated effective tax rates. These rates are revised, if necessary, at the end of each successive interim period to reflect the current estimates of the annual effective tax rates. The effective rate in 2020 is higher than the statutory rate due to the tax benefit related to the impact of stock-based compensation which increased the tax benefit during three months ended March 31, 2020. ​ The Company believes that the positions taken on its income tax returns for open tax years will be sustained upon examination by the Internal Revenue Service (“IRS”). Therefore, the Company has not recorded any liability for uncertain tax positions under ASC 740, Income Taxes ​ During the three months ended March 31, 2020, there were no material changes to the amount of the Company’s unrecognized tax benefits or to any assumptions regarding the amount of its ASC 740 liability. ​ ​ In the Company’s opinion, adequate tax liabilities have been established for all open years. However, the amount of these tax liabilities could be revised in the near term if estimates of the Company’s ultimate liability are revised. ​

Share Repurchase Program

Share Repurchase Program	3 Months Ended
	Mar. 31, 2020
Share Repurchase Program
Share Repurchase Program	11. Share Repurchase Program ​ On August 3, 2007, the Board of Directors approved a share repurchase program of up to $30,000 of the Company’s outstanding common shares. The Board of Directors had cumulatively authorized increases to the existing share repurchase program of up to $150,000 of its outstanding common shares. Under the program, the Company may repurchase shares of its common stock for cash in public or private transactions, in the open market or otherwise. The timing of such repurchases and actual number of shares repurchased will depend on a variety of factors including price, market conditions and applicable regulatory and corporate requirements. The program does not require the Company to repurchase any specific number of shares and it may be modified, suspended or terminated at any time without prior notice. ​ During the three months ended March 31, 2020, the Company purchased 143,292 shares on the open market under the program at a cost of $10,392. No share purchases were made by the Company under the program during the three months ended March 31, 2019. As of March 31, 2020, the Company has purchased 2,422,862 shares at a cost of $94,227. As of December 31, 2019, the Company had purchased 2,279,570 shares at a cost of $83,835.

Leases

Leases	3 Months Ended
	Mar. 31, 2020
Leases
Leases	12. Leases ​ The Company has various non-cancelable, long-term operating leases, the largest of which are for office space including the corporate headquarters, VIP claims centers and law offices. Other operating leases consist of auto leases and various office equipment. The Company has no finance leases. Our leases have remaining lease terms of options to extend ​ The Company adopted ASU 2016-02, ASU 2018-10 and ASU 2018-11 effective January 1, 2019 (“the application date”) using the required modified retrospective transition approach. In accordance with the guidance, the Company has elected not to adjust comparative periods. As such ASC 842 will be applied to each lease that had commenced as of the application date with a cumulative effect adjustment as of that date. All periods before the application date presented in the financial statements will not change and the guidance in ASC 840 will apply. The Company has elected to apply the package of practical expedients provided in ASC 842 to all leases. In addition, the Company has elected not to apply the hindsight practical expedient or the land easement practical expedient. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2020 ​ ​ 2019 Operating lease cost ​ $ 1,151 ​ $ 1,154 ​ ​ Other information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2020 ​ ​ 2019 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ Operating cash flows from operating leases $ 1,282 ​ $ 1,256 Weighted average remaining lease term ​ ​ ​ ​ ​ Operating leases ​ 8.23 Years ​ ​ 9.25 Years Weighted average discount rate ​ ​ ​ ​ ​ Operating leases ​ 2.39% ​ ​ 3.45% ​ Maturities of lease liabilities were as follows: ​ ​ ​ ​ 2020 $ 3,730 2021 4,817 2022 4,283 2023 3,880 2024 ​ 3,875 2025 and after 15,405 Total lease payments ​ 35,990 Less imputed interest ​ (1,734) Total $ 34,256 ​

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2020
Subsequent Events
Subsequent Events	​ 13. Subsequent Events ​ On April 14, 2020, the Company announced the Safety Personal Auto Relief Credit, a 15% policyholder credit which will be applied to personal auto policies for the months of April and May. The Company’s decision to return a portion of premium payments to its customers is a recognition of the impact of government-mandated stay-at-home measures, which are reducing the number of vehicles on the roads and miles driven, and consequently, the number of claims filed. The Company estimates that this premium refund will be approximately $12,000, which will be recognized in the second quarter of 2020. ​ ​

Earnings per Weighted Average_2

Earnings per Weighted Average Common Share (Tables)	3 Months Ended
	Mar. 31, 2020
Earnings per Weighted Average Common Share
Computation of basic and diluted EPS	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2020 ​ 2019 ​ (Loss) Earnings attributable to common shareholders - basic and diluted: ​ ​ ​ ​ ​ ​ ​ Net (loss) income from continuing operations ​ $ (1,990) ​ $ 29,946 ​ Allocation of loss (income) for participating shares ​ ​ 10 ​ ​ (167) ​ Net (loss) income from continuing operations attributed to common shareholders ​ $ (1,980) ​ $ 29,779 ​ (Loss) Earnings per share denominator - basic and diluted ​ ​ ​ ​ ​ ​ ​ Total weighted average common shares outstanding, including participating shares ​ ​ 15,304,758 ​ ​ 15,225,774 ​ Less: weighted average participating shares ​ ​ (73,974) ​ ​ (84,970) ​ Basic (loss) earnings per share denominator ​ ​ 15,230,784 ​ ​ 15,140,804 ​ Common equivalent shares- non-vested performance stock grants ​ 116,299 ​ 164,981 ​ Diluted (loss) earnings per share denominator ​ 15,347,083 ​ 15,305,785 ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic (loss) earnings per share ​ $ (0.13) ​ $ 1.97 ​ Diluted (loss) earnings per share ​ $ (0.13) ​ $ 1.95 ​ ​ ​ ​ ​ ​ ​ ​ ​ Undistributed (loss) earnings attributable to common shareholders - basic and diluted: ​ ​ ​ ​ ​ ​ ​ Net (loss) income from continuing operations attributable to common shareholders -Basic ​ $ (0.13) ​ $ 1.97 ​ Dividends declared ​ ​ (0.90) ​ ​ (0.80) ​ Undistributed (loss) earnings ​ $ (1.03) ​ $ 1.17 ​ ​ ​ ​ ​ ​ ​ ​ ​ Net (loss) income from continuing operations attributable to common shareholders -Diluted ​ $ (0.13) ​ $ 1.95 ​ Dividends declared ​ ​ (0.90) ​ ​ (0.80) ​ Undistributed (loss) earnings ​ $ (1.03) ​ $ 1.15 ​

Share-Based Compensation (Table

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2020
Share-Based Compensation
Schedule of restricted stock and performance-based restricted stock activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Shares Weighted ​ Performance-based Weighted ​ ​ Under ​ Average ​ Shares Under ​ Average ​ ​ Restriction ​ Fair Value ​ Restriction ​ Fair Value Outstanding at beginning of year 78,202 ​ $ 79.09 ​ 84,105 ​ $ 79.34 Granted 34,799 ​ ​ 90.10 ​ 36,649 (1) ​ 84.68 Vested and unrestricted (43,480) ​ ​ 78.07 ​ (42,123) ​ ​ 73.55 Forfeited ​ — ​ ​ — ​ (1,868) ​ ​ 84.61 Outstanding at end of period 69,521 ​ $ 85.24 ​ 76,763 ​ $ 84.94 (1) Includes a true-up of previously awarded performance-based restricted share awards. The updated shares were calculated based on the attainment of pre-established performance objectives and granted under the 2002 Incentive Plan.

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2020
Investments
Gross unrealized gains and losses on investments in securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost or Allowance for Gross Unrealized Estimated ​ ​ Amortized ​ Expected Credit ​ ​ ​ ​ ​ Fair ​ ​ Cost ​ Losses ​ Gains ​ Losses (3) ​ Value U.S. Treasury securities ​ $ 1,823 ​ $ — ​ $ 60 ​ $ — ​ $ 1,883 Obligations of states and political subdivisions ​ 224,800 ​ — ​ 8,924 ​ (34) ​ 233,690 Residential mortgage-backed securities (1) ​ 288,122 ​ — ​ 12,998 ​ (103) ​ 301,017 Commercial mortgage-backed securities ​ 105,678 ​ — ​ 3,553 ​ (165) ​ 109,066 Other asset-backed securities ​ 26,659 ​ — ​ 63 ​ (1,415) ​ 25,307 Corporate and other securities ​ 512,777 ​ (2,510) ​ 9,127 ​ (24,902) ​ 494,492 Subtotal, fixed maturity securities ​ 1,159,859 ​ (2,510) ​ 34,725 ​ (26,619) ​ 1,165,455 Equity securities (2) ​ 153,359 ​ — ​ 13,874 ​ (17,345) ​ 149,888 Other invested assets (4) ​ 41,881 ​ — ​ — ​ — ​ 41,881 Totals ​ $ 1,355,099 ​ $ (2,510) ​ $ 48,599 ​ $ (43,964) ​ $ 1,357,224 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cost or Gross Unrealized Estimated ​ ​ Amortized ​ ​ ​ ​ ​ Fair ​ ​ Cost ​ Gains ​ Losses ​ Value U.S. Treasury securities ​ $ 1,504 ​ $ 8 ​ $ — ​ $ 1,512 ​ Obligations of states and political subdivisions ​ 241,597 ​ 9,799 ​ — ​ 251,396 ​ Residential mortgage-backed securities (1) ​ 301,503 ​ 6,608 ​ (909) ​ 307,202 ​ Commercial mortgage-backed securities ​ 106,902 ​ 3,233 ​ (397) ​ 109,738 ​ Other asset-backed securities ​ 36,068 ​ 218 ​ (64) ​ 36,222 ​ Corporate and other securities ​ 504,783 ​ 18,455 ​ (1,268) ​ 521,970 ​ Subtotal, fixed maturity securities ​ 1,192,357 ​ 38,321 ​ (2,638) ​ 1,228,040 ​ Equity securities (2) ​ 151,121 ​ 27,879 ​ (1,363) ​ 177,637 ​ Other invested assets (4) ​ 37,278 ​ — ​ — ​ 37,278 ​ Totals ​ $ 1,380,756 ​ $ 66,200 ​ $ (4,001) ​ $ 1,442,955 ​ (1) Residential mortgage-backed securities consists primarily of obligations of U.S. Government agencies including collateralized mortgage obligations issued, guaranteed and/or insured by the following issuers: Government National Mortgage Association (GNMA), Federal Home Loan Mortgage Corporation (FHLMC), Federal National Mortgage Association (FNMA) and the Federal Home Loan Bank (FHLB). (2) Equity securities include common stock, preferred stock, mutual funds and interests in mutual funds held to fund the Company’s executive deferred compensation plan. (3) The Company’s investment portfolio included 733 and 229 securities in an unrealized loss position at March 31, 2020 and December 31, 2019, respectively. (4) Other invested assets are accounted for under the equity method which approximated fair value.
Amortized cost and the estimated fair value of fixed maturity securities, by maturity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ Amortized Estimated ​ ​ Cost ​ Fair Value Due in one year or less ​ $ 51,519 ​ $ 51,881 Due after one year through five years ​ 295,621 ​ 287,963 Due after five years through ten years ​ 311,755 ​ 305,990 Due after ten years through twenty years ​ 79,555 ​ 83,326 Due after twenty years ​ 950 ​ 906 Asset-backed securities ​ 420,459 ​ 435,389 Totals ​ $ 1,159,859 ​ $ 1,165,455
Gross realized gains and losses on sales of investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 Gross realized gains ​ ​ ​ ​ ​ ​ ​ Fixed maturity securities ​ $ 889 ​ $ 115 ​ Equity securities ​ 1,576 ​ 953 ​ Gross realized losses ​ ​ ​ ​ ​ ​ ​ Fixed maturity securities ​ (301) ​ (667) ​ Equity securities ​ (2,795) ​ (565) ​ Net realized losses on investments ​ $ (631) ​ $ (164) ​ ​ ​ ​ ​ ​ ​ ​ ​
Gross unrealized losses included in the Company's investment portfolio and the fair value of those securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ ​ Less than 12 Months ​ 12 Months or More ​ Total ​ Estimated Unrealized Estimated Unrealized Estimated Unrealized ​ ​ Fair Value ​ Losses ​ Fair Value ​ Losses ​ Fair Value ​ Losses U.S. Treasury securities ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — Obligations of states and political subdivisions ​ 656 ​ 34 ​ — ​ — ​ 656 ​ 34 Residential mortgage-backed securities ​ 20,492 ​ 99 ​ 195 ​ 4 ​ 20,687 ​ 103 Commercial mortgage-backed securities ​ 22,272 ​ 165 ​ — ​ — ​ 22,272 ​ 165 Other asset-backed securities ​ 14,840 ​ ​ 534 ​ ​ 8,202 ​ ​ 881 ​ ​ 23,042 ​ ​ 1,415 Corporate and other securities ​ 233,543 ​ 23,185 ​ 8,758 ​ 1,717 ​ 242,301 ​ 24,902 Subtotal, fixed maturity securities ​ 291,803 ​ 24,017 ​ 17,155 ​ 2,602 ​ 308,958 ​ 26,619 Equity securities ​ 67,644 ​ 13,991 ​ 9,909 ​ 3,354 ​ 77,553 ​ 17,345 Total temporarily impaired securities ​ $ 359,447 ​ $ 38,008 ​ $ 27,064 ​ $ 5,956 ​ $ 386,511 ​ $ 43,964 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2019 ​ ​ Less than 12 Months ​ 12 Months or More ​ Total ​ Estimated Unrealized Estimated Unrealized Estimated Unrealized ​ ​ Fair Value ​ Losses ​ Fair Value ​ Losses ​ Fair Value ​ Losses U.S. Treasury securities ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — ​ $ — Obligations of states and political subdivisions ​ — ​ — ​ — ​ — ​ — ​ — Residential mortgage-backed securities ​ 61,933 ​ 409 ​ 31,655 ​ 500 ​ 93,588 ​ 909 Commercial mortgage-backed securities ​ 36,398 ​ 397 ​ 866 ​ — ​ 37,264 ​ 397 Other asset-backed securities ​ 21,281 ​ ​ 64 ​ ​ 462 ​ ​ — ​ 21,743 ​ 64 Corporate and other securities ​ 26,386 ​ 481 ​ 13,718 ​ 787 ​ 40,104 ​ 1,268 Subtotal, fixed maturity securities ​ 145,998 ​ 1,351 ​ 46,701 ​ 1,287 ​ 192,699 ​ 2,638 Equity securities ​ 8,849 ​ 391 ​ 14,143 ​ 972 ​ 22,992 ​ 1,363 Total temporarily impaired securities ​ $ 154,847 ​ $ 1,742 ​ $ 60,844 ​ $ 2,259 ​ $ 215,691 ​ $ 4,001
Reconciliation of beginning and ending balances of allowance for expected credit losses on fixed maturities classified as available for sale	​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, 2020 ​ ​ ​ ​ ​ ​ Corporate and other ​ ​ securities Balance January 1, 2020 ​ $ — Credit losses on securities with no previously recorded credit losses ​ 2,510 Net increases (decreases) in allowance on previously impaired securities ​ — Reduction due to sales ​ — Writeoffs charged against allowance ​ — Recoveries of amounts previously written off ​ — Balance March 31, 2020 ​ $ 2,510
Components of net investment income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 Interest on fixed maturity securities ​ $ 9,759 ​ $ 11,127 ​ Dividends on equity securities ​ 1,206 ​ 1,082 ​ Equity in earnings of other invested assets ​ 516 ​ 282 ​ Interest on other assets ​ 7 ​ 9 ​ Total investment income ​ 11,488 ​ 12,500 ​ Investment expenses ​ 778 ​ 749 ​ Net investment income ​ $ 10,710 ​ $ 11,751 ​
Fair Value Measurements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2020 ​ Total Level 1 Inputs Level 2 Inputs Level 3 Inputs U.S. Treasury securities ​ $ 1,883 ​ $ — ​ $ 1,883 ​ $ — Obligations of states and political subdivisions ​ 233,690 ​ — ​ 233,690 ​ — Residential mortgage-backed securities ​ 301,017 ​ — ​ 301,017 ​ — Commercial mortgage-backed securities ​ 109,066 ​ — ​ 109,066 ​ — Other asset-backed securities ​ 25,307 ​ — ​ 25,307 ​ — Corporate and other securities ​ 494,492 ​ — ​ 494,492 ​ — Equity securities ​ 117,082 ​ 115,396 ​ — ​ 1,686 Total investment securities ​ $ 1,282,537 ​ $ 115,396 ​ $ 1,165,455 ​ $ 1,686 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2019 ​ Total Level 1 Inputs Level 2 Inputs Level 3 Inputs U.S. Treasury securities ​ $ 1,512 ​ $ — ​ $ 1,512 ​ $ — Obligations of states and political subdivisions ​ 251,396 ​ — ​ 251,396 ​ — Residential mortgage-backed securities ​ 307,202 ​ — ​ 307,202 ​ — Commercial mortgage-backed securities ​ 109,738 ​ — ​ 109,738 ​ — Other asset-backed securities ​ 36,222 ​ — ​ 36,222 ​ — Corporate and other securities ​ 521,970 ​ — ​ 521,970 ​ — Equity securities ​ 144,877 ​ 144,361 ​ — ​ 516 Total investment securities ​ $ 1,372,917 ​ $ 144,361 ​ $ 1,228,040 ​ $ 516
Changes in Company's Level 3 Fair value securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 ​ ​ Level 3 ​ Level 3 ​ ​ Fair Value ​ Fair Value ​ ​ Securities ​ Securities Balance at beginning of period ​ $ 516 ​ $ 680 ​ Net gains and losses included in earnings ​ — ​ — ​ Net gains included in other comprehensive income ​ — ​ — ​ Purchases ​ 1,170 ​ — ​ Sales ​ ​ — ​ ​ (297) ​ Transfers into Level 3 ​ ​ — ​ — ​ Transfers out of Level 3 ​ — ​ — ​ Balance at end of period ​ $ 1,686 ​ $ 383 ​ Amount of total losses included in earnings attributable to the change in unrealized losses related to assets still held at end of period ​ $ — ​ $ — ​

Allowance for Expected Credit_2

Allowance for Expected Credit Losses (Tables)	3 Months Ended
	Mar. 31, 2020
Allowance for Expected Credit Losses
Accounts receivable, net of allowance for expected credit losses	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accounts Receivable Net of Allowance for Expected Credit Losses ​ ​ Allowance for Expected Credit Losses Balance January 1, 2020 ​ $ 193,369 ​ $ 578 Current period change for expected credit losses ​ ​ ​ 1,576 Writeoffs of uncollectable accounts receivable ​ ​ ​ (1,820) Balance March 31, 2020 ​ $ 189,671 ​ $ 334

Loss and Loss Adjustment Expe_2

Loss and Loss Adjustment Expense Reserves (Tables)	3 Months Ended
	Mar. 31, 2020
Loss and Loss Adjustment Expense Reserves
Schedule of reconciliation of beginning and ending reserves for losses and loss adjustment expenses (LAE)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2020 2019 Reserves for losses and LAE at beginning of year ​ $ 610,566 ​ $ 584,719 Less receivable from reinsurers related to unpaid losses and LAE ​ (122,372) ​ (108,398) Net reserves for losses and LAE at beginning of year ​ 488,194 ​ 476,321 Incurred losses and LAE, related to: ​ ​ ​ ​ ​ ​ Current year ​ 130,330 ​ 138,007 Prior years ​ (9,584) ​ (11,980) Total incurred losses and LAE ​ 120,746 ​ 126,027 Paid losses and LAE related to: ​ ​ ​ ​ ​ ​ Current year ​ 48,745 ​ 58,796 Prior years ​ 72,839 ​ 70,990 Total paid losses and LAE ​ 121,584 ​ 129,786 Net reserves for losses and LAE at end of period ​ 487,356 ​ 472,562 Plus receivable from reinsurers related to unpaid losses and LAE ​ 121,337 ​ 109,200 Reserves for losses and LAE at end of period ​ $ 608,693 ​ $ 581,762

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2020
Leases
Schedule of operating lease cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2020 ​ ​ 2019 Operating lease cost ​ $ 1,151 ​ $ 1,154
Schedule of other information related to leases	​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ ​ 2020 ​ ​ 2019 Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ Operating cash flows from operating leases $ 1,282 ​ $ 1,256 Weighted average remaining lease term ​ ​ ​ ​ ​ Operating leases ​ 8.23 Years ​ ​ 9.25 Years Weighted average discount rate ​ ​ ​ ​ ​ Operating leases ​ 2.39% ​ ​ 3.45%
Schedule of the maturities of lease liabilities	​ ​ ​ ​ 2020 $ 3,730 2021 4,817 2022 4,283 2023 3,880 2024 ​ 3,875 2025 and after 15,405 Total lease payments ​ 35,990 Less imputed interest ​ (1,734) Total $ 34,256

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Mar. 31, 2020
Fixed maturity securities, allowance for expected credit losses		$ 2,510
Accounting Standards Update 2016-02
Cumulative effect of change in accounting principle	$ 35,984
Accounting Standards Update 2017-08
Cumulative effect of change in accounting principle	$ 2,373

Earnings per Weighted Average_3

Earnings per Weighted Average Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
(Loss) Earnings attributable to common shareholders - basic and diluted:
Net (loss) income from continuing operations	$ (1,990)	$ 29,946
Allocation of loss (income) for participating shares	10	(167)
Net (loss) income from continuing operations attributed to common shareholders	$ (1,980)	$ 29,779
Total weighted average common shares outstanding, including participating shares	15,304,758	15,225,774
Less: weighted average participating shares	(73,974)	(84,970)
Basic (loss) earnings per share denominator	15,230,784	15,140,804
Common equivalent shares- non-vested performance stock grants	116,299	164,981
Diluted (loss) earnings per share denominator	15,347,083	15,305,785
Basic (loss) earnings per share (in dollars per share)	$ (0.13)	$ 1.97
Diluted (loss) earnings per share (in dollars per share)	(0.13)	1.95
Undistributed (loss) earnings attributable to common shareholders - basic and diluted:
Net (loss) income from continuing operations attributable to common shareholders -Basic	(0.13)	1.97
Dividends declared	(0.90)	(0.80)
Undistributed (loss) earnings	(1.03)	1.17
Undistributed (loss) earnings attributable to common shareholders - diluted
Net (loss) income from continuing operations attributable to common shareholders -Diluted	(0.13)	1.95
Dividends declared	(0.90)	(0.80)
Undistributed (loss) earnings	$ (1.03)	$ 1.15
Non Vested Performance Stock Grants
Undistributed (loss) earnings attributable to common shareholders - diluted
Antidilutive common shares	0	0

Share-Based Compensation (Detai

Share-Based Compensation (Details) - shares	Mar. 31, 2020	Apr. 02, 2018
2018 Plan and 2002 Plan
Maximum number of shares of common stock with respect to which awards may be granted	2,850,000
2018 Long Term Incentive Plan
Maximum number of shares of common stock with respect to which awards may be granted		350,000
Number of shares available for future grant	234,170

Share-Based Compensation Restri

Share-Based Compensation Restricted Stock Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Weighted Average Fair Value
Unrecognized compensation expense related to non-vested restricted stock awards	$ 9,428
Weighted average period expected for recognition of compensation expense related to non-vested restricted stock awards	1 year 9 months 18 days
Total fair value of the shares that were vested and unrestricted during the period	$ 6,493	$ 7,771
Compensation Expense, Net of Tax	1,378	1,361
Income tax benefits from compensation expense	$ 366	$ 362
Performance-based Shares Under Restriction
Shares Under Restriction
Outstanding at beginning of year (in shares)	84,105
Granted (in shares)	36,649
Vested and unrestricted (in shares)	(42,123)
Forfeited (in shares)	(1,868)
Outstanding at end of period (in shares)	76,763
Weighted Average Fair Value
Outstanding at beginning of year (in dollars per share)	$ 79.34
Granted (in dollars per share)	84.68
Vested and unrestricted (in dollars per share)	73.55
Forfeited (in dollars per share)	84.61
Outstanding at end of period (in dollars per share)	$ 84.94
Restricted Stock
Shares Under Restriction
Outstanding at beginning of year (in shares)	78,202
Granted (in shares)	34,799
Vested and unrestricted (in shares)	(43,480)
Outstanding at end of period (in shares)	69,521
Weighted Average Fair Value
Outstanding at beginning of year (in dollars per share)	$ 79.09
Granted (in dollars per share)	90.10
Vested and unrestricted (in dollars per share)	78.07
Outstanding at end of period (in dollars per share)	$ 85.24
Restricted Stock | Minimum
Share-Based Compensation
Actual Payouts (as a percent)	0.00%
Restricted Stock | Maximum
Share-Based Compensation
Actual Payouts (as a percent)	200.00%
Restricted Stock | Non-executive
Share-Based Compensation
Vesting period	5 years
Restricted Stock | Executives and non-executives (2018 and after)
Share-Based Compensation
Vesting period	3 years
Restricted Stock | First anniversary of grant date | Executives and non-executives (2018 and after)
Share-Based Compensation
Actual Payouts (as a percent)	30.00%
Restricted Stock | Second anniversary of grant date | Executives and non-executives (2018 and after)
Share-Based Compensation
Actual Payouts (as a percent)	30.00%
Restricted Stock | Third anniversary of grant date | Executives and non-executives (2018 and after)
Share-Based Compensation
Actual Payouts (as a percent)	40.00%

Investments (Details)

Investments (Details) $ in Thousands	Mar. 31, 2020USD ($)security	Dec. 31, 2019USD ($)security
Marketable Securities
Fixed maturity securities, amortized cost	$ 1,159,859	$ 1,192,357
Fixed maturity securities, allowance for expected credit losses	(2,510)
Fixed maturity securities, Gross Unrealized Gains	34,725	38,321
Fixed maturity securities, Gross Unrealized Losses	(26,619)	(2,638)
Fixed maturity securities, Estimated Fair Value	1,165,455	1,228,040
Equity securities, Cost or Amortized Cost	153,359	151,121
Equity securities, Estimated Fair Value	149,888	177,637
Other invested assets, Cost or Amortized Cost	41,881	37,278
Cost or Amortized Cost	1,355,099	1,380,756
Gross Unrealized Gains	48,599	66,200
Gross Unrealized Losses	(43,964)	(4,001)
Estimated Fair Value	$ 1,357,224	$ 1,442,955
Number of securities in an unrealized loss position | security	733	229
U.S. Treasury securities
Marketable Securities
Fixed maturity securities, amortized cost	$ 1,823	$ 1,504
Fixed maturity securities, Gross Unrealized Gains	60	8
Fixed maturity securities, Estimated Fair Value	1,883	1,512
Obligations of states and political subdivisions
Marketable Securities
Fixed maturity securities, amortized cost	224,800	241,597
Fixed maturity securities, Gross Unrealized Gains	8,924	9,799
Fixed maturity securities, Gross Unrealized Losses	(34)
Fixed maturity securities, Estimated Fair Value	233,690	251,396
Residential mortgage-backed securities
Marketable Securities
Fixed maturity securities, amortized cost	288,122	301,503
Fixed maturity securities, Gross Unrealized Gains	12,998	6,608
Fixed maturity securities, Gross Unrealized Losses	(103)	(909)
Fixed maturity securities, Estimated Fair Value	301,017	307,202
Commercial mortgage-backed securities
Marketable Securities
Fixed maturity securities, amortized cost	105,678	106,902
Fixed maturity securities, Gross Unrealized Gains	3,553	3,233
Fixed maturity securities, Gross Unrealized Losses	(165)	(397)
Fixed maturity securities, Estimated Fair Value	109,066	109,738
Other asset-backed securities
Marketable Securities
Fixed maturity securities, amortized cost	26,659	36,068
Fixed maturity securities, Gross Unrealized Gains	63	218
Fixed maturity securities, Gross Unrealized Losses	(1,415)	(64)
Fixed maturity securities, Estimated Fair Value	25,307	36,222
Corporate and other securities
Marketable Securities
Fixed maturity securities, amortized cost	512,777	504,783
Fixed maturity securities, allowance for expected credit losses	(2,510)	0
Fixed maturity securities, Gross Unrealized Gains	9,127	18,455
Fixed maturity securities, Gross Unrealized Losses	(24,902)	(1,268)
Fixed maturity securities, Estimated Fair Value	494,492	521,970
Equity securities
Marketable Securities
Equity securities, Cost or Amortized Cost	153,359	151,121
Equity securities, Gross Unrealized Gains	13,874	27,879
Equity securities, Gross Unrealized Losses	(17,345)	(1,363)
Equity securities, Estimated Fair Value	149,888	177,637
Other invested assets
Marketable Securities
Other invested assets, Cost or Amortized Cost	41,881	37,278
Other invested assets, Estimated Fair Value	$ 41,881	$ 37,278

Investments Amortized Cost and

Investments Amortized Cost and Estimated Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized Cost
Due in one year or less, Amortized Cost	$ 51,519
Due after one year through five years, Amortized Cost	295,621
Due after five years though ten years, Amortized Cost	311,755
Due after ten years through twenty years, Amortized Cost	79,555
Due after twenty years, Amortized Cost	950
Asset-backed securities, Amortized Cost	420,459
Totals, Amortized Cost	1,159,859	$ 1,192,357
Estimated Fair Value
Due in one year or less, Fair Value	51,881
Due after one year through five years, Fair Value	287,963
Due after five years through ten years, Fair Value	305,990
Due after ten years through twenty years, Fair Value	83,326
Due after twenty years, Fair Value	906
Asset-backed securities, Fair Value	435,389
Totals, Fair Value	$ 1,165,455	$ 1,228,040

Investments Gross Realized Gain

Investments Gross Realized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Investments
Gross realized gains fixed maturity securities	$ 889	$ 115
Gross realized gains equity securities	1,576	953
Gross realized losses fixed maturities	(301)	(667)
Gross realized losses equity securities	(2,795)	(565)
Net realized losses on investments	$ (631)	$ (164)

Investments Gross Unrealized Lo

Investments Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Marketable Securities
Estimated Fair Value, Less than 12 Months	$ 359,447	$ 154,847
Estimated Fair Value, 12 Months or More	27,064	60,844
Estimated Fair Value, Total	386,511	215,691
Unrealized Losses, Less than 12 Months	38,008	1,742
Unrealized Losses, 12 Months or More	5,956	2,259
Unrealized Losses, Total	43,964	4,001
Fixed maturity securities
Marketable Securities
Estimated Fair Value, Less than 12 Months	291,803	145,998
Estimated Fair Value, 12 Months or More	17,155	46,701
Estimated Fair Value, Total	308,958	192,699
Unrealized Losses, Less than 12 Months	24,017	1,351
Unrealized Losses, 12 Months or More	2,602	1,287
Unrealized Losses, Total	26,619	2,638
Obligations of states and political subdivisions
Marketable Securities
Estimated Fair Value, Less than 12 Months	656
Estimated Fair Value, Total	656
Unrealized Losses, Less than 12 Months	34
Unrealized Losses, Total	34
Residential mortgage-backed securities
Marketable Securities
Estimated Fair Value, Less than 12 Months	20,492	61,933
Estimated Fair Value, 12 Months or More	195	31,655
Estimated Fair Value, Total	20,687	93,588
Unrealized Losses, Less than 12 Months	99	409
Unrealized Losses, 12 Months or More	4	500
Unrealized Losses, Total	103	909
Commercial mortgage-backed securities
Marketable Securities
Estimated Fair Value, Less than 12 Months	22,272	36,398
Estimated Fair Value, 12 Months or More		866
Estimated Fair Value, Total	22,272	37,264
Unrealized Losses, Less than 12 Months	165	397
Unrealized Losses, Total	165	397
Other asset-backed securities
Marketable Securities
Estimated Fair Value, Less than 12 Months	14,840	21,281
Estimated Fair Value, 12 Months or More	8,202	462
Estimated Fair Value, Total	23,042	21,743
Unrealized Losses, Less than 12 Months	534	64
Unrealized Losses, 12 Months or More	881
Unrealized Losses, Total	1,415	64
Corporate and other securities
Marketable Securities
Estimated Fair Value, Less than 12 Months	233,543	26,386
Estimated Fair Value, 12 Months or More	8,758	13,718
Estimated Fair Value, Total	242,301	40,104
Unrealized Losses, Less than 12 Months	23,185	481
Unrealized Losses, 12 Months or More	1,717	787
Unrealized Losses, Total	24,902	1,268
Equity securities
Equity Securities
Estimated Fair Value, Less than 12 Months	67,644	8,849
Estimated Fair Value, 12 Months or More	9,909	14,143
Estimated Fair Value, Total	77,553	22,992
Unrealized Losses, Less than 12 Months	13,991	391
Unrealized Losses, 12 Months or More	3,354	972
Unrealized Losses, Total	$ 17,345	$ 1,363

Investments Other (Details)

Investments Other (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020USD ($)item	Mar. 31, 2019USD ($)item	Dec. 31, 2019USD ($)
Other than Temporary Impairment, Credit Losses Recognized in Earnings
Other-than-temporary impairments recognized under ASC 320		$ 220
Available-for-sale investments	$ 1,165,455		$ 1,228,040
Short-term Investments	$ 0		$ 0
Level 3 Securities Held Number | item	1	1
Subprime mortgage debt securities
Other-Than-Temporary Impairments
Securities held	$ 0

Investments Allowance for Expec

Investments Allowance for Expected Credit Losses (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Marketable Securities
Credit losses on securities with no previously recorded credit losses	$ 2,510
Balance	2,510
Corporate and other securities
Marketable Securities
Balance	0
Credit losses on securities with no previously recorded credit losses	2,510
Balance	$ 2,510

Investments Components of Net I

Investments Components of Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Components of net investment income
Interest on fixed maturity securities	$ 9,759	$ 11,127
Dividends on equity securities	1,206	1,082
Equity in earnings of other invested assets	516	282
Interest on other assets	7	9
Total investment income	11,488	12,500
Investment expenses	778	749
Net investment income	$ 10,710	$ 11,751

Investments Fair Value Measurem

Investments Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	$ 1,165,455	$ 1,228,040
Equity securities, Estimated Fair Value	149,888	177,637
Level 1 Inputs
Fair value of financial instruments
Marketable Securities, Total	115,396	144,361
Level 1 Inputs | Equity securities
Fair value of financial instruments
Equity securities, Estimated Fair Value	115,396	144,361
Level 2 Inputs
Fair value of financial instruments
Marketable Securities, Total	1,165,455	1,228,040
Level 2 Inputs | U.S. Treasury securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	1,883	1,512
Level 2 Inputs | Obligations of states and political subdivisions
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	233,690	251,396
Level 2 Inputs | Residential mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	301,017	307,202
Level 2 Inputs | Commercial mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	109,066	109,738
Level 2 Inputs | Other asset-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	25,307	36,222
Level 2 Inputs | Corporate and other securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	494,492	521,970
Level 3 Inputs
Fair value of financial instruments
Marketable Securities, Total	1,686	516
Level 3 Inputs | Equity securities
Fair value of financial instruments
Equity securities, Estimated Fair Value	1,686	516
Total
Fair value of financial instruments
Marketable Securities, Total	1,282,537	1,372,917
Total | U.S. Treasury securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	1,883	1,512
Total | Obligations of states and political subdivisions
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	233,690	251,396
Total | Residential mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	301,017	307,202
Total | Commercial mortgage-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	109,066	109,738
Total | Other asset-backed securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	25,307	36,222
Total | Corporate and other securities
Fair value of financial instruments
Fixed maturity securities, Estimated Fair Value	494,492	521,970
Total | Equity securities
Fair value of financial instruments
Equity securities, Estimated Fair Value	$ 117,082	$ 144,877

Investments Level 3 and Other (

Investments Level 3 and Other (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Transfers between Levels
Transfers from Level 1 to Level 2	$ 0	$ 0
Transfers from Level 2 to Level 1	0	0
Changes in the Company's Level 3 fair value securities
Balance at beginning of period	516	680
Purchases	1,170
Sales		(297)
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Balance at end of period	1,686	$ 383
Alternative investments fair value	$ 32,806
Period of advance notice before quarter end	45 days
Accounting Standards Update 2015-07
Changes in the Company's Level 3 fair value securities
Alternative investments fair value	$ 32,806		$ 32,760

Allowance for Expected Credit_3

Allowance for Expected Credit Losses Balances of Premiums Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Accounts Receivable, after Allowance for Credit Loss [Abstract]
Accounts receivable, net of allowance for expected credit losses	$ 189,671	$ 193,369
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance	578
Current period change for expected credit losses	1,576
Writeoffs of uncollectable accounts receivable	(1,820)
Balance	$ 334

Allowance for Expected Credit_4

Allowance for Expected Credit Losses (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Expected credit losses	$ 0
CAR Commercial Automobile Program and the Taxi/Limo Program
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of reinsurance recoverable	97.00%
Other Contracts
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of reinsurance recoverable	3.00%

Loss and Loss Adjustment Expe_3

Loss and Loss Adjustment Expense Reserves (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Loss and Loss Adjustment Expense Reserves
Reserves for losses and LAE at beginning of year	$ 610,566	$ 584,719
Less receivable from reinsurers related to unpaid losses and LAE	(122,372)	(108,398)
Net reserves for losses and LAE at beginning of year	488,194	476,321
Incurred losses and LAE, related to:
Current year	130,330	138,007
Prior years	(9,584)	(11,980)
Total incurred losses and LAE	120,746	126,027
Paid losses and LAE related to:
Current year	48,745	58,796
Prior years	72,839	70,990
Total paid losses and LAE	121,584	129,786
Net reserves for losses and LAE at end of period	487,356	472,562
Plus receivable from reinsurers related to unpaid losses and LAE	121,337	109,200	$ 122,372
Reserves for losses and LAE at end of period	608,693	581,762
Prior years	$ 9,584	$ 11,980

Loss and Loss Adjustment Expe_4

Loss and Loss Adjustment Expense Reserves - Disclosure of Incurred and Paid Claims Development to the Liability for Unpaid claims and Claim Adjustment Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims [Abstract]
Prior years	$ 9,584	$ 11,980

Debt (Details)

Debt (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 17, 2020	Dec. 31, 2019
Debt
Outstanding amount	$ 30,000
Revolving Credit Agreement | LIBOR rate
Debt
Variable interest rate basis	LIBOR
Spread on variable rate (as a percent)	1.25%
Revolving Credit Agreement | Prime rate
Debt
Variable interest rate basis	prime rate
Revolving Credit Agreement | Federal Funds Effective Swap Rate
Debt
Variable interest rate basis	federal funds rate
Spread on variable rate (as a percent)	1.25%
Additional spread on variable rate (as a percent)	0.50%
RBS Citizens
Debt
Maximum borrowing capacity	$ 30,000
RBS Citizens | Revolving Credit Agreement
Debt
Current borrowing capacity	30,000
Maximum borrowing capacity	50,000
Default trigger, principal amount	10,000
Outstanding amount	$ 0			$ 0
Commitment fee (as a percent)	0.25%	0.25%
F H L B Boston
Debt
Outstanding amount			$ 30,000	$ 0
Advance term	5 years
Interest rate percentage	1.42%
Interest Expense, Borrowings	$ 18	$ 0
Maximum borrowing capacity using eligible invested assets as collateral	$ 283,999

Share Repurchase Program (Detai

Share Repurchase Program (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Aug. 03, 2007
Share Repurchase Program
Share Repurchase Program	$ 150,000			$ 30,000
Number of common shares purchased during period under the program	143,292	0
Acquisition of treasury stock	$ 10,392
Treasury stock shares	2,422,862		2,279,570
Treasury stock, at cost	$ 94,227		$ 83,835

Leases - Remaining Lease Term (

Leases - Remaining Lease Term (Details)	3 Months Ended
	Mar. 31, 2020
Leases
Operating lease, existence of option to extend	true
Operating lease, renewal term	5 years
Minimum
Leases
Operating lease, remaining lease term	1 year
Maximum
Leases
Operating lease, remaining lease term	10 years

Leases (Details)

Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases
Operating lease cost	$ 1,151	$ 1,154
Operating cash flows from operating leases	$ 1,282	$ 1,256
Weighted average remaining lease term Operating leases	8 years 2 months 23 days	9 years 3 months
Weighted average discount rate Operating leases	2.39%	3.45%

Leases (Maturities) (Details)

Leases (Maturities) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Leases
2020	$ 3,730
2021	4,817
2022	4,283
2023	3,880
2024	3,875
Thereafter	15,405
Total lease payments	35,990
Less imputed interest	(1,734)
Total	$ 34,256	$ 33,998

Subsequent Events (Details)

Subsequent Events (Details) - Personal auto policies - Subsequent event - USD ($) $ in Thousands	Apr. 14, 2020	Jun. 30, 2020
Subsequent Event [Line Items]
Percentage of policyholders applied for refund	15.00%
Insurance premium refund		$ 12,000