AMERISAFE (AMSF) 10-Q 2 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Jul. 30, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Trading Symbol	AMSF
Entity Registrant Name	AMERISAFE INC
Entity Central Index Key	0001018979
Entity Current Reporting Status	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity File Number	001-12251
Entity Tax Identification Number	752069407
Entity Address, Address Line One	2301 Highway 190 West
Entity Address, City or Town	DeRidder
Entity Address, State or Province	Louisiana
Entity Address, Postal Zip Code	70634
City Area Code	337
Local Phone Number	463-9052
Entity Common Stock, Shares Outstanding		19,298,261

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investments:
Fixed maturity securities—held-to-maturity, at amortized cost (fair value $629,207 and $616,772 in 2019 and 2018, respectively)	$ 610,950	$ 613,878
Fixed maturity securities—available-for-sale, at fair value (cost $445,117 and $479,772 in 2019 and 2018, respectively)	457,893	478,730
Equity securities, at fair value (cost $22,582 and $19,962 in 2019 and 2018, respectively)	24,070	18,651
Short-term investments	70,146	14,231
Total investments	1,163,059	1,125,490
Cash and cash equivalents	51,246	40,344
Amounts recoverable from reinsurers	103,695	112,006
Premiums receivable, net of allowance	175,020	162,478
Deferred income taxes	19,461	21,852
Accrued interest receivable	10,086	10,197
Property and equipment, net	5,957	6,258
Deferred policy acquisition costs	20,550	19,734
Other assets	22,019	17,572
Total assets	1,571,093	1,515,931
Liabilities:
Reserves for loss and loss adjustment expenses	795,046	798,409
Unearned premiums	156,889	149,296
Amounts held for others	44,064	41,388
Policyholder deposits	46,095	46,795
Insurance-related assessments	30,253	28,258
Federal income tax payable	1,325	3,412
Accounts payable and other liabilities	38,325	38,611
Payable for investments purchased	9,653
Total liabilities	1,121,650	1,106,169
Shareholders’ equity:
Common stock: voting—$0.01 par value authorized shares—50,000,000 in 2019 and 2018; 20,556,511 and 20,528,230 shares issued and 19,298,261 and 19,269,980 shares outstanding in 2019 and 2018, respectively	205	205
Additional paid-in capital	212,493	211,431
Treasury stock, at cost (1,258,250 shares in 2019 and 2018)	(22,370)	(22,370)
Accumulated earnings	248,975	221,328
Accumulated other comprehensive income (loss), net	10,140	(832)
Total shareholders’ equity	449,443	409,762
Total liabilities and shareholders’ equity	$ 1,571,093	$ 1,515,931

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Fixed maturity securities, fair value	$ 629,207	$ 616,772
Fixed maturity securities, cost	445,117	479,772
Equity securities, cost	$ 22,582	$ 19,962
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	20,556,511	20,528,230
Common stock, shares outstanding	19,298,261	19,269,980
Treasury stock, shares	1,258,250	1,258,250

Consolidated Statements of Inco

Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues
Gross premiums written	$ 87,018	$ 93,702	$ 180,125	$ 191,044
Ceded premiums written	(2,204)	(2,369)	(4,634)	(4,699)
Net premiums written	84,814	91,333	175,491	186,345
Net premiums earned	82,951	88,995	167,899	176,305
Net investment income	8,169	7,303	16,184	14,512
Net realized losses on investments	(82)	(1,111)	(23)	(1,142)
Net unrealized gains (losses) on equity securities	642	76	2,800	(314)
Fee and other income	73	117	83	194
Total revenues	91,753	95,380	186,943	189,555
Expenses
Loss and loss adjustment expenses incurred	48,868	52,076	98,482	105,238
Underwriting and certain other operating costs	7,416	7,985	14,968	15,831
Commissions	6,243	6,616	12,611	13,110
Salaries and benefits	6,059	6,681	12,806	12,607
Policyholder dividends	998	1,092	2,098	2,425
Total expenses	69,584	74,450	140,965	149,211
Income before income taxes	22,169	20,930	45,978	40,344
Income tax expense	4,279	3,974	8,688	7,219
Net income	$ 17,890	$ 16,956	$ 37,290	$ 33,125
Earnings per share
Basic	$ 0.93	$ 0.88	$ 1.94	$ 1.73
Diluted	$ 0.93	$ 0.88	$ 1.93	$ 1.72
Shares used in computing earnings per share
Basic	19,245,592	19,208,601	19,237,401	19,197,925
Diluted	19,306,953	19,266,735	19,316,276	19,275,883
Cash dividends declared per common share	$ 0.25	$ 0.22	$ 0.50	$ 0.44

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 17,890	$ 16,956	$ 37,290	$ 33,125
Other comprehensive income:
Unrealized gain (loss) on debt securities, net of tax	4,980	153	10,972	(5,695)
Change in deferred tax valuation allowance	198
Comprehensive income	$ 23,068	$ 17,109	$ 48,262	$ 27,430

Consolidated Statement of Chang

Consolidated Statement of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Accumulated Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance at Dec. 31, 2017	$ 425,423	$ 204	$ 210,081	$ (22,370)	$ 233,896	$ 3,612
Beginning Balance, Shares at Dec. 31, 2017		20,504,165
Treasury Stock Beginning Balance, Shares at Dec. 31, 2017				(1,258,250)
Comprehensive income:
Impact of adoption of ASU | ASU 2016-01 [Member]	614				614
Impact of adoption of ASU | ASU 2018-02 [Member]	(414)				(414)
Net income	33,125				33,125
Other comprehensive income:
Change in unrealized gains (losses), net of tax	(5,695)					(5,695)
Comprehensive income	27,430
Common stock issued upon exercise of options	$ 67		67
Common stock issued upon exercise of options, Shares	15,000	15,000
Common stock issued	$ 196	$ 1	195
Common stock issued, Shares		9,065
Share-based compensation	552		552
Dividends to shareholders	(8,477)				(8,477)
Ending Balance at Jun. 30, 2018	445,391	$ 205	210,895	$ (22,370)	258,744	(2,083)
Ending Balance, Shares at Jun. 30, 2018		20,528,230
Treasury Stock Ending Balance, Shares at Jun. 30, 2018				(1,258,250)
Beginning Balance at Mar. 31, 2018	432,068	$ 205	210,441	$ (22,370)	246,028	(2,236)
Beginning Balance, Shares at Mar. 31, 2018		20,519,165
Treasury Stock Beginning Balance, Shares at Mar. 31, 2018				(1,258,250)
Comprehensive income:
Impact of adoption of ASU | ASU 2016-01 [Member]	(1)				(1)
Net income	16,956				16,956
Other comprehensive income:
Change in unrealized gains (losses), net of tax	153					153
Comprehensive income	17,109
Common stock issued upon exercise of options	(1)	$ (1)
Common stock issued	196	$ 1	195
Common stock issued, Shares		9,065
Share-based compensation	259		259
Dividends to shareholders	(4,239)				(4,239)
Ending Balance at Jun. 30, 2018	445,391	$ 205	210,895	$ (22,370)	258,744	(2,083)
Ending Balance, Shares at Jun. 30, 2018		20,528,230
Treasury Stock Ending Balance, Shares at Jun. 30, 2018				(1,258,250)
Beginning Balance at Dec. 31, 2018	$ 409,762	$ 205	211,431	$ (22,370)	221,328	(832)
Beginning Balance, Shares at Dec. 31, 2018	20,528,230	20,528,230
Treasury Stock Beginning Balance, Shares at Dec. 31, 2018	(1,258,250)			(1,258,250)
Comprehensive income:
Impact of adoption of ASU | ASU 2016-02 [Member]	$ (1)				(1)
Net income	37,290				37,290
Other comprehensive income:
Change in unrealized gains (losses), net of tax	10,972					10,972
Comprehensive income	48,262
Common stock issued upon exercise of options	$ 20		20
Common stock issued upon exercise of options, Shares	5,000	5,000
Common stock issued	$ 560		560
Common stock issued, Shares		23,281
Share-based compensation	482		482
Dividends to shareholders	(9,642)				(9,642)
Ending Balance at Jun. 30, 2019	$ 449,443	$ 205	212,493	$ (22,370)	248,975	10,140
Ending Balance, Shares at Jun. 30, 2019	20,556,511	20,556,511
Treasury Stock Ending Balance, Shares at Jun. 30, 2019	(1,258,250)			(1,258,250)
Beginning Balance at Mar. 31, 2019	$ 430,405	$ 205	211,700	$ (22,370)	235,908	4,962
Beginning Balance, Shares at Mar. 31, 2019		20,533,230
Treasury Stock Beginning Balance, Shares at Mar. 31, 2019				(1,258,250)
Comprehensive income:
Net income	17,890				17,890
Other comprehensive income:
Change in unrealized gains (losses), net of tax	4,980					4,980
Change in deferred tax valuation allowance	198					198
Comprehensive income	23,068
Common stock issued	560		560
Common stock issued, Shares		23,281
Share-based compensation	233		233
Dividends to shareholders	(4,823)				(4,823)
Ending Balance at Jun. 30, 2019	$ 449,443	$ 205	$ 212,493	$ (22,370)	$ 248,975	$ 10,140
Ending Balance, Shares at Jun. 30, 2019	20,556,511	20,556,511
Treasury Stock Ending Balance, Shares at Jun. 30, 2019	(1,258,250)			(1,258,250)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Operating activities
Net income	$ 37,290	$ 33,125
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	449	488
Net amortization of investments	4,483	5,979
Deferred income taxes	(526)	831
Net realized losses on investments	23	1,142
Net unrealized (gains) losses on equity securities	(2,800)	314
Share-based compensation	509	782
Changes in operating assets and liabilities:
Premiums receivable, net	(12,542)	(15,658)
Accrued interest receivable	111	177
Deferred policy acquisition costs	(816)	(1,350)
Amounts held by others	1	(7,855)
Other assets	(947)	942
Reserves for loss and loss adjustment expenses	(3,363)	11,756
Unearned premiums	7,593	10,040
Reinsurance balances	8,317	(8,828)
Amounts held for others and policyholder deposits	1,976	1,787
Accounts payable and other liabilities	(189)	3,312
Net cash provided by operating activities	39,569	36,984
Investing activities
Purchases of investments held-to-maturity	(67,571)	(38,129)
Purchases of investments available-for-sale	(27,356)	(52,211)
Purchases of equity securities	(2,620)	(4,339)
Purchases of short-term investments	(79,224)	(100,059)
Proceeds from maturities of investments held-to-maturity	73,865	52,584
Proceeds from sales and maturities of investments available-for-sale	60,494	66,480
Proceeds from sales of equity securities		282
Proceeds from sales and maturities of short-term investments	23,679	13,465
Proceeds from redemptions of other investments		130
Purchases of property and equipment	(148)	(1,004)
Net cash used in investing activities	(18,881)	(62,801)
Financing activities
Proceeds from stock option exercises	20	67
Finance lease purchases	(23)
Dividends to shareholders	(9,783)	(8,633)
Net cash used in financing activities	(9,786)	(8,566)
Change in cash and cash equivalents	10,902	(34,383)
Cash and cash equivalents at beginning of period	40,344	55,559
Cash and cash equivalents at end of period	$ 51,246	$ 21,176

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	Note 1. Basis of Presentation AMERISAFE, Inc. (the “Company”) is an insurance holding company incorporated in the state of Texas. The accompanying unaudited consolidated financial statements include the accounts of AMERISAFE and its subsidiaries: American Interstate Insurance Company (“AIIC”) and its insurance subsidiaries, Silver Oak Casualty, Inc. (“SOCI”) and American Interstate Insurance Company of Texas (“AIICTX”), Amerisafe Risk Services, Inc. (“RISK”) and Amerisafe General Agency, Inc. (“AGAI”). AIIC and SOCI are property and casualty insurance companies organized under the laws of the state of Nebraska. AIICTX is a property and casualty insurance company organized under the laws of the state of Texas. RISK, a wholly owned subsidiary of the Company, is a claims and safety service company currently servicing only affiliated insurance companies. AGAI, a wholly owned subsidiary of the Company, is a general agent for the Company. AGAI sells insurance, which is underwritten by AIIC, SOCI and AIICTX, as well as by nonaffiliated insurance carriers. The assets and operations of AGAI are not significant to that of the Company and its consolidated subsidiaries. The terms “AMERISAFE,” the “Company,” “we,” “us” or “our” refer to AMERISAFE, Inc. and its consolidated subsidiaries, as the context requires. The Company provides workers’ compensation insurance for small to mid-sized employers engaged in hazardous industries, principally construction, trucking, logging and lumber, manufacturing, and agriculture. Assets and revenues of AIIC and its subsidiaries represent at least 95% of comparable consolidated amounts of the Company for each of the six months ended June 30, 2019 and 2018. In the opinion of management of the Company, the accompanying unaudited consolidated financial statements contain all adjustments (consisting of normal recurring accruals) necessary to present fairly the financial position, the results of operations and cash flows for the periods presented. The unaudited consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q under the Securities Exchange Act of 1934 and therefore do not include all information and footnotes to be in conformity with accounting principles generally accepted in the United States (“GAAP”). The results for the interim periods are not necessarily indicative of the results of operations that may be expected for the year. The unaudited consolidated financial statements contained herein should be read in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2018. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of our assets, liabilities, revenues and expenses and related disclosures. Some of the estimates result from judgments that can be subjective and complex and, consequently, actual results in future periods might differ from these estimates. Adopted Accounting Guidance In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The new guidance requires a lessee to recognize a lease liability and a right of use asset for all leases extending beyond twelve months. This standard was effective for us beginning in the first quarter of 2019. We elected the new transition method under the transition guidance within the new standard. Therefore, prior comparative periods are not adjusted. We also elected the package of practical expedients, which among other things, allows us to carryforward the historical lease classification. We made an accounting policy election not to recognize lease assets and lease liabilities for short-term operating leases. Adoption of the new guidance resulted in the Company recognizing right-of-use assets of $0.4 million and lease liabilities of $0.3 million. The cumulative effect adjustment to the opening balance of retained earnings was minimal. Adoption of this new guidance did not have a material effect on the Company’s consolidated financial statements as the Company does not have any significant leases. Prospective Accounting Guidance In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses. The current guidance delays the recognition of credit losses until a probable loss has occurred. The new guidance requires credit losses for securities measured at amortized cost to be determined using current expected credit loss estimates. These estimates are to be derived from historical, current and reasonable supporting forecasts, including prepayments and estimates, and will be recorded through a valuation account. The same method will be used for available-for-sale securities, but the valuation account will be limited to the amount by which the fair value is below amortized cost. The standard is effective for us in the first quarter of 2020. Implementation of the new guidance requires a modified retrospective approach without restatement, which means the first cumulative adjustment required will be a charge to retained earnings, with subsequent changes in the valuation account reported in the income statement. The financial statement impact will be determined by the nature of the portfolio held and the economic conditions at the time of implementation. The Company has formed an internal working group to evaluate the new standard and develop an implementation strategy. The group has researched data, developed models and methodologies and is working toward implementation. The Company will continue to monitor and evaluate the financial impact as the implementation date approaches. All other issued but not yet effective accounting and reporting standards as of June 30, 2019 are either not applicable to the Company or are not expected to have a material impact on the Company.

Stock Options and Restricted St

Stock Options and Restricted Stock	6 Months Ended
	Jun. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Options and Restricted Stock	Note 2. Stock Options and Restricted Stock As of June 30, 2019, the Company has two equity incentive plans: the AMERISAFE Non-Employee Director Restricted Stock Plan (the “Restricted Stock Plan”) and the AMERISAFE 2012 Equity and Incentive Compensation Plan (the “2012 Incentive Plan”). In connection with the approval of the 2012 Incentive Plan by the Company’s shareholders, no further grants were made under the AMERISAFE 2005 Incentive Plan. There are no outstanding options or restricted stock awards under the 2005 Incentive Plan. See Note 12 to our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2018 for additional information regarding the Company’s incentive plans. During the six months ended June 30, 2019, the Company issued 9,391 shares of common stock pursuant to vested performance awards and 9,000 shares of restricted common stock to executive officers. During the six months ended June 30, 2019, the Company issued 4,890 shares of restricted common stock to non-employee directors. The market value of the shares issued totaled $1.4 million. During the six months ended June 30, 2018, the Company issued 3,304 shares of common stock pursuant to vested performance awards to executive officers and 5,761 shares of restricted common stock to non-employee directors. The market value of the shares issued totaled $0.5 million. During the six months ended June 30, 2019 and 2018, options to purchase 5,000 and 15,000 shares of common stock were exercised, respectively. In connection with these exercises, the Company received $20 thousand of stock option proceeds in the current year and $67 thousand of stock option proceeds in the same period of 2018. The Company recognized a negative share-based compensation expense of $0.1 million in the quarter ended June 30, 2019 due to lower estimates of variable share price based incentive compensation costs. The Company recognized an expense of $0.8 million for the same period in 2018. The Company recognized share-based compensation expense of $0.5 million in the six months ended June 30, 2019 and $0.8 million for the same period in 2018.

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Earnings Per Share	Note 3. Earnings Per Share The Company computes earnings per share (“EPS”) in accordance with FASB Accounting Standards Codification (“ASC”) Topic 260, Earnings Per Share Basic EPS is calculated by dividing net income by the weighted-average number of common shares outstanding during the period. The diluted EPS calculation includes potential common shares assumed issued under the treasury stock method, which reflects the potential dilution that would occur if any outstanding options were exercised or restricted stock becomes vested. Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 (in thousands, except share and per share amounts) Basic EPS Net income $ 17,890 $ 16,956 $ 37,290 $ 33,125 Basic weighted average common shares 19,245,592 19,208,601 19,237,401 19,197,925 Basic earnings per common share $ 0.93 $ 0.88 $ 1.94 $ 1.73 Diluted EPS Net income $ 17,890 $ 16,956 $ 37,290 $ 33,125 Diluted weighted average common shares: Weighted average common shares 19,245,592 19,208,601 19,237,401 19,197,925 Stock options and restricted stock 61,361 58,134 78,875 77,958 Diluted weighted average common shares 19,306,953 19,266,735 19,316,276 19,275,883 Diluted earnings per common share $ 0.93 $ 0.88 $ 1.93 $ 1.72

Investments

Investments	6 Months Ended
	Jun. 30, 2019
Investments Debt And Equity Securities [Abstract]
Investments	Note 4. Investments The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as held-to-maturity at June 30, 2019 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 439,103 $ 15,966 $ (36 ) $ 455,033 Corporate bonds 108,756 1,425 (17 ) 110,164 U.S. agency-based mortgage-backed securities 12,465 523 (12 ) 12,976 U.S. Treasury securities and obligations of U.S. government agencies 49,677 430 (29 ) 50,078 Asset-backed securities 949 10 (3 ) 956 Totals $ 610,950 $ 18,354 $ (97 ) $ 629,207 The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as available-for-sale at June 30, 2019 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 220,385 $ 9,852 $ (15 ) $ 230,222 Corporate bonds 151,705 2,953 (39 ) 154,619 U.S. agency-based mortgage-backed securities 11,904 6 (58 ) 11,852 U.S. Treasury securities and obligations of U.S. government agencies 61,123 301 (224 ) 61,200 Totals $ 445,117 $ 13,112 $ (336 ) $ 457,893 The gross unrealized gains and losses on, and the cost of equity securities at June 30, 2019 are summarized as follows: Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Equity securities: Domestic common stock $ 22,582 $ 1,488 $ — $ 24,070 Total equity securities $ 22,582 $ 1,488 $ — $ 24,070 The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as held-to-maturity at December 31, 2018 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 445,922 $ 5,109 $ (2,084 ) $ 448,947 Corporate bonds 91,762 62 (455 ) 91,369 U.S. agency-based mortgage-backed securities 8,102 327 (80 ) 8,349 U.S. Treasury securities and obligations of U.S. government agencies 67,042 340 (339 ) 67,043 Asset-backed securities 1,050 22 (8 ) 1,064 Totals $ 613,878 $ 5,860 $ (2,966 ) $ 616,772 The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as available-for-sale at December 31, 2018 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 231,848 $ 3,515 $ (2,118 ) $ 233,245 Corporate bonds 173,904 243 (933 ) 173,214 U.S. agency-based mortgage-backed securities 12,835 — (320 ) 12,515 U.S. Treasury securities and obligations of U.S. government agencies 61,185 — (1,429 ) 59,756 Totals $ 479,772 $ 3,758 $ (4,800 ) $ 478,730 The gross unrealized gains and losses on, and the cost of equity securities at December 31, 2018 are summarized as follows: Cost Gross Gains Gross Losses Fair Value (in thousands) Equity securities: Domestic common stock $ 19,962 $ 30 $ (1,341 ) $ 18,651 Total equity securities $ 19,962 $ 30 $ (1,341 ) $ 18,651 A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as held-to-maturity at June 30, 2019, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 79,934 $ 80,374 After one year through five years 216,626 220,476 After five years through ten years 84,179 87,047 After ten years 216,797 227,378 U.S. agency-based mortgage-backed securities 12,465 12,976 Asset-backed securities 949 956 Totals $ 610,950 $ 629,207 A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as available-for-sale at June 30, 2019, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 49,966 $ 50,018 After one year through five years 158,125 159,944 After five years through ten years 46,069 47,983 After ten years 179,053 188,096 U.S. agency-based mortgage-backed securities 11,904 11,852 Totals $ 445,117 $ 457,893 The following table summarizes the fair value and gross unrealized losses on securities, aggregated by major investment category and length of time that the individual securities have been in a continuous unrealized loss position: Less Than 12 Months 12 Months or Greater Total Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses (in thousands) June 30, 2019 Held-to-Maturity Fixed maturity securities: States and political subdivisions $ 6,038 $ 19 $ 11,835 $ 17 $ 17,873 $ 36 Corporate bonds — — 15,306 17 15,306 17 U.S. agency-based mortgage-backed securities — — 2,201 12 2,201 12 U.S. Treasury securities and obligations of U.S. government agencies — — 8,362 29 8,362 29 Asset-backed securities — — 177 3 177 3 Total held-to-maturity securities 6,038 19 37,881 78 43,919 97 Available-for-Sale Fixed maturity securities: States and political subdivisions $ — $ — $ 7,008 $ 15 $ 7,008 $ 15 Corporate bonds — — 22,346 39 22,346 39 U.S. agency-based mortgage-backed securities — — 10,588 58 10,588 58 U.S. Treasury securities and obligations of U.S. government agencies — — 39,120 224 39,120 224 Total available-for-sale securities — — 79,062 336 79,062 336 Total $ 6,038 $ 19 $ 116,943 $ 414 $ 122,981 $ 433 Less Than 12 Months 12 Months or Greater Total Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses (in thousands) December 31, 2018 Held-to-Maturity Fixed maturity securities: States and political subdivisions $ 28,369 $ 59 $ 180,550 $ 2,025 $ 208,919 $ 2,084 Corporate bonds 17,448 36 48,315 419 65,763 455 U.S. agency-based mortgage-backed securities — — 2,287 80 2,287 80 U.S. Treasury securities and obligations of U.S. government agencies 2,865 4 46,486 335 49,351 339 Asset-backed securities — — 525 8 525 8 Total held-to-maturity securities 48,682 99 278,163 2,867 326,845 2,966 Available-for-Sale Fixed maturity securities: States and political subdivisions $ 16,109 $ 81 $ 76,255 $ 2,037 $ 92,364 $ 2,118 Corporate bonds 59,099 279 70,306 654 129,405 933 U.S. agency-based mortgage-backed securities — — 12,515 320 12,515 320 U.S. Treasury securities and obligations of U.S. government agencies — — 59,756 1,429 59,756 1,429 Total available-for-sale securities 75,208 360 218,832 4,440 294,040 4,800 Total $ 123,890 $ 459 $ 496,995 $ 7,307 $ 620,885 $ 7,766 At June 30, 2019, we held 66 individual fixed maturity securities that were in an unrealized loss position, of which 61 individual fixed maturity securities were in a continuous unrealized loss position for longer than 12 months. During the second quarter of 2019, we recognized through income $0.6 million of net unrealized gains on equity securities held as of June 30, 2019. During the second quarter of 2018, we recognized through income $0.1 million of net unrealized gains on equity securities held as of June 30, 2018. During the six months ended June 30, 2019, we recognized through income $2.8 million of net unrealized gains on equity securities held as of June 30, 2019. During the six months ended June 30, 2018, we recognized through income $0.3 million of net unrealized losses on equity securities held as of June 30, 2018. Investment income is recognized as it is earned. The discount or premium on fixed maturity securities is amortized using the “constant yield” method. Anticipated prepayments, where applicable, are considered when determining the amortization of premiums or discounts. Realized investment gains and losses are determined using the specific identification method. We regularly review our investment portfolio to evaluate the existence of other-than-temporary declines in the fair value of investments. We consider various factors in determining if a decline in the fair value of an individual security is other-than-temporary. The key factors we consider are: • any reduction or elimination of preferred dividends, or nonpayment of scheduled principal or interest payments; • the financial condition and near-term prospects of the issuer of the applicable security, including any specific events that may affect its operations or earnings; • how long and by how much the fair value of the security has been below its cost or amortized cost; • any downgrades of the security by a rating agency; • our intent not to sell the security for a sufficient time period for it to recover its value; • the likelihood of being required to sell the security before the recovery of its value; and • an evaluation as to whether there are any credit losses on debt securities. We reviewed all securities with unrealized losses in accordance with the impairment policy described above. We determined that the unrealized losses in the fixed maturity securities portfolio related primarily to changes in market interest rates since the date of purchase, current conditions in the capital markets and the impact of those conditions on market liquidity and prices generally. We expect to recover the carrying value of these securities as it is not more likely than not that we will be required to sell the securities before the recovery of its amortized cost basis. During the three and six months ended June 30, 2019 and 2018, there were no impairment losses recognized for other-than-temporary declines in the fair value of our investments. Net realized losses in the quarter ended June 30, 2019 were $0.1 million resulting from the call of fixed maturity securities. Net realized losses in the quarter ended June 30, 2018 were $1.1 million resulting from the sale of fixed maturity securities classified as available-for-sale. Net realized losses in the six months ended June 30, 2019 were immaterial. Net realized losses in the six months ended June 30, 2018 were $1.1 million resulting from the sale of fixed maturity securities classified as available-for-sale.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Note 5. Income Taxes In accordance with FASB ASC Topic 740, “Income Taxes,” we provide for the recognition and measurement of deferred income tax benefits based on the likelihood of their realization in future years. As of June 30, 2019, the Company established a valuation allowance of $0.2 million against its deferred income tax benefits. The Company recognizes interest and penalties related to uncertain tax positions in income tax expense. There were no uncertain tax positions recognized for the periods ended June 30, 2019 and 2018. Tax years 2015 through 2018 are subject to examination by the federal and state taxing authorities.

Loss Reserves

Loss Reserves	6 Months Ended
	Jun. 30, 2019
Insurance [Abstract]
Loss Reserves	Note 6. Loss Reserves We record reserves for estimated losses under insurance policies that we write and for loss adjustment expenses related to the investigation and settlement of policy claims. Our reserves for loss and loss adjustment expenses represent the estimated cost of all reported and unreported loss and loss adjustment expenses incurred and unpaid as of a given point in time. The reserves for loss and loss adjustment expenses are estimated using individual case-basis valuations, statistical analyses and estimates based upon experience for unreported claims and their associated loss and loss adjustment expenses. Such estimates may be more or less than the amounts ultimately paid when the claims are settled. The estimates are subject to the effects of trends in loss severity and frequency. Although considerable variability is inherent in these estimates, management believes that the reserves for loss and loss adjustment expenses are adequate. The estimates are continually reviewed internally and periodically evaluated with our independent actuary. Adjustments are made as experience develops and new information becomes known. Any such adjustments are included in income from current operations. See Note 9 to our consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2018 for additional information regarding the Company’s loss and loss adjustment expense development. The following table provides the Company’s liability for unpaid loss and loss adjustment expenses, net of related amounts recoverable from reinsurers, for the six months ended June 30, 2019 and 2018: Six Months Ended June 30, 2019 2018 (in thousands) Balance, beginning of period $ 798,409 $ 771,845 Less amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 107,216 84,889 Net balance, beginning of period 691,193 686,956 Add incurred related to: Current accident year 121,727 126,060 Prior accident years (23,245 ) (20,822 ) Total incurred 98,482 105,238 Less paid related to: Current accident year 15,926 18,386 Prior accident years 77,362 84,194 Total paid 93,288 102,580 Net balance, end of period 696,387 689,614 Add amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 98,659 93,987 Balance, end of period $ 795,046 $ 783,601 The foregoing reconciliation reflects favorable development of the net reserves at June 30, 2019 and June 30, 2018. The favorable development reduced loss and loss adjustment expenses incurred by $23.2 million and $20.8 million in 2019 and 2018, respectively. The revisions to the Company’s reserves reflect new information gained by claims adjusters in the normal course of adjusting claims and is reflected in the financial statements when the information becomes available. It is typical for more serious claims to take several years or longer to settle and the Company continually revises estimates as more information about claimants’ medical conditions and potential disability becomes known and the claims get closer to being settled. Multiple factors can cause loss development both unfavorable and favorable. The favorable loss development we experienced across accident years was largely due to favorable case reserve development from closed claims and claims where the worker had reached maximum medical improvement.

Comprehensive Income and Accumu

Comprehensive Income and Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Comprehensive Income and Accumulated Other Comprehensive Income	Note 7. Comprehensive Income and Accumulated Other Comprehensive Income Comprehensive income was $23.1 million for the three months ended June 30, 2019, compared to $17.1 million for the three months ended June 30, 2018. Comprehensive income was $48.3 million for the six months ended June 30, 2019, compared to $27.4 million for the same period in 2018. The difference between net income as reported and comprehensive income was due to changes in unrealized gains and losses, net of tax on available-for-sale debt securities. Comprehensive income includes net income plus unrealized gains (losses) on our available-for-sale investment securities, net of tax. In reporting comprehensive income on a net basis in the statements of comprehensive income, we used a 21 percent tax rate in 2019 and 2018. The following table illustrates the changes in the balance of each component of accumulated other comprehensive income for each period presented in the interim financial statements. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in thousands) Beginning balance $ 4,962 $ (2,236 ) $ (832 ) $ 3,612 Other comprehensive income (loss) before reclassification 5,001 (449 ) 10,889 (5,863 ) Amounts reclassified from accumulated other comprehensive income (21 ) 602 83 168 Change in deferred tax valuation allowance 198 — — — Net current period other comprehensive income (loss) 5,178 153 10,972 (5,695 ) Ending balance $ 10,140 $ (2,083 ) $ 10,140 $ (2,083 ) The sale or other-than-temporary impairment of an available-for-sale security results in amounts being reclassified from accumulated other comprehensive income to current period net income. The effects of reclassifications out of accumulated other comprehensive income by the respective line items of net income are presented in the following table. Component of Accumulated Other Three Months Ended Six Months Ended Affected line item in the Comprehensive Income June 30, June 30, statement of income 2019 2018 2019 2018 (in thousands) Unrealized gains (losses) on available-for-sale securities $ 26 $ (762 ) $ (105 ) $ (466 ) Net realized losses on investments 26 (762 ) (105 ) (466 ) Income before income taxes (5 ) 160 22 44 Income tax expense $ 21 $ (602 ) $ (83 ) $ (422 ) Net income

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 8. Fair Value Measurements The Company carries available-for-sale securities at fair value in our consolidated financial statements and determines fair value measurements and disclosure in accordance with FASB ASC Topic 820, Fair Value Measurements and Disclosures. The Company determines the fair values of its financial instruments based on the fair value hierarchy established in ASC Topic 820, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard defines fair value, describes three levels of inputs that may be used to measure fair value, and expands disclosures about fair value measurements. Fair value is defined in ASC Topic 820 as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value is the price to sell an asset or transfer a liability and, therefore, represents an exit price, not an entry price. Fair value is the exit price in the principal market (or, if lacking a principal market, the most advantageous market) in which the reporting entity would transact. Fair value is a market-based measurement, not an entity-specific measurement, and, as such, is determined based on the assumptions that market participants would use in pricing the asset or liability. The exit price objective of a fair value measurement applies regardless of the reporting entity’s intent and/or ability to sell the asset or transfer the liability at the measurement date. ASC Topic 820 requires the use of valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities. The income approach uses valuation techniques to convert future amounts, such as cash flows or earnings, to a single present value amount on a discounted basis. The cost approach is based on the amount that currently would be required to replace the service capacity of an asset, also known as current replacement cost. Valuation techniques used to measure fair value are to be consistently applied. In ASC Topic 820, inputs refer broadly to the assumptions that market participants would use in pricing the asset or liability, including assumptions about risk, for example, the risk inherent in a particular valuation technique used to measure fair value (such as a pricing model) and/or the risk inherent in the inputs to the valuation technique. Inputs may be observable or unobservable: • Observable inputs are inputs that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from sources independent of the reporting entity. • Unobservable inputs are inputs that reflect the reporting entity’s own assumptions about the assumptions market participants would use in pricing the asset or liability developed based on the best information available in the circumstances. Valuation techniques used to measure fair value are intended to maximize the use of observable inputs and minimize the use of unobservable inputs. ASC Topic 820 establishes a fair value hierarchy that prioritizes the use of inputs used in valuation techniques into the following three levels: • Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. • Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability, or inputs that are derived principally from or corroborated by observable market data. • Level 3 inputs are unobservable inputs for the asset or liability. Unobservable inputs are to be used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at the measurement date. In general, fair value is based upon quoted market prices, where available. If such quoted market prices are not available, fair value is based upon internally developed models that primarily use, as inputs, observable market-based parameters. The fair values of the Company’s investments are based upon prices provided by an independent pricing service. The Company has reviewed these prices for reasonableness and has not adjusted any prices received from the independent provider. Securities reported at fair value utilizing Level 1 inputs represent assets whose fair value is determined based upon observable unadjusted quoted market prices for identical assets in active markets. Level 2 securities represent assets whose fair value is determined using observable market information such as previous day trade prices, quotes from less active markets or quoted prices of securities with similar characteristics. There were no transfers between Level 1 and Level 2 during the six months ended June 30, 2019. At June 30, 2019, assets measu r June 30, 2019 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Financial instruments carried at fair value, classified as a part of: Securities available-for-sale—fixed maturity: States and political subdivisions $ — $ 230,222 $ — $ 230,222 Corporate bonds — 154,619 — 154,619 U.S. agency-based mortgage-backed securities — 11,852 — 11,852 U.S. Treasury securities 61,200 — — 61,200 Total securities available-for-sale—fixed maturity 61,200 396,693 — 457,893 Equity securities: Domestic common stock 24,070 — — 24,070 Total $ 85,270 $ 396,693 $ — $ 481,963 At June 30, 2019, assets measured at amortized cost are summarized below: June 30, 2019 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Securities held-to-maturity—fixed maturity: States and political subdivisions $ — $ 455,033 $ — $ 455,033 Corporate bonds — 110,164 — 110,164 U.S. agency-based mortgage-backed securities — 12,976 — 12,976 U.S. Treasury securities 7,882 — — 7,882 Obligations of U.S. government agencies — 42,196 — 42,196 Asset-backed securities — 956 — 956 Total held-to-maturity $ 7,882 $ 621,325 $ — $ 629,207 At December 31, 2018, assets measured at fair value on a recurring basis are summarized below: December 31, 2018 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Financial instruments carried at fair value, classified as part of: Securities available-for-sale—fixed maturity: States and political subdivisions $ — $ 233,245 $ — $ 233,245 Corporate bonds — 173,214 — 173,214 U.S. agency-based mortgage-backed securities — 12,515 — 12,515 U.S. Treasury securities and obligations of U.S. government agencies 59,756 — — 59,756 Total securities available-for-sale—fixed maturity $ 59,756 $ 418,974 $ — $ 478,730 Equity securities: Domestic common stock 18,651 — — 18,651 Total $ 78,407 $ 418,974 $ — $ 497,381 At December 31, 2018, assets measured at amortized cost are summarized below: December 31, 2018 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Securities held-to-maturity—fixed maturity: States and political subdivisions $ — $ 448,947 $ — $ 448,947 Corporate bonds — 91,369 — 91,369 U.S. agency-based mortgage-backed securities — 8,349 — 8,349 U.S. Treasury securities 7,111 — — 7,111 Obligations of U.S. government agencies — 59,932 — 59,932 Asset-backed securities — 1,064 — 1,064 Total held-to-maturity $ 7,111 $ 609,661 $ — $ 616,772 The Company determines fair value amounts for financial instruments using available third-party market information. When such information is not available, the Company determines the fair value amounts using appropriate valuation methodologies. Nonfinancial instruments such as real estate, property and equipment, deferred policy acquisition costs, deferred income taxes and loss and loss adjustment expense reserves are excluded from the fair value disclosure. At June 30, 2019, the Company did not hold any securities measured at fair value on a nonrecurring basis due to impairment. Cash and Cash Equivalents —The carrying amounts reported in the accompanying consolidated balance sheets for these financial instruments approximate their fair values, which are characterized as Level 1 assets. Investments —The fair values for fixed maturity and equity securities are based on prices obtained from an independent pricing service. Equity and treasury securities are characterized as Level 1 assets, as their fair values are based on quoted prices in active markets. Fixed maturity securities, other than treasury securities, are characterized as Level 2 assets, as their fair values are determined using observable market inputs. Short Term Investments —The carrying amounts reported in the accompanying consolidated balance sheets for these financial instruments approximate their fair values. These securities are characterized as Level 2 assets in the fair value hierarchy. The following table summarizes the carrying values and corresponding fair values for financial instruments: As of June 30, 2019 As of December 31, 2018 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Assets: Fixed maturity securities—held-to-maturity $ 610,950 $ 629,207 $ 613,878 $ 616,772 Fixed maturity securities—available-for-sale 457,893 457,893 478,730 478,730 Equity securities 24,070 24,070 18,651 18,651 Short-term investments 70,146 70,146 14,231 14,231 Cash and cash equivalents 51,246 51,246 40,344 40,344

Treasury Stock

Treasury Stock	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Treasury Stock	Note 9. Treasury Stock The Company’s Board of Directors initiated a share repurchase program in February 2010. In October 2016, the Board reauthorized this program with a limit of $25.0 million with no expiration date. There were no shares repurchased under this program in the six months ended June 30, 2019 and 2018.

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Leases	Note 10. Leases The Company has operating and finance leases for office space and equipment. Our leases have remaining lease terms of 2 months 55 months 5 years Supplemental balance sheet information related to leases is as follows: June 30, 2019 Balance Sheet Classification (in thousands) Operating leases: Operating lease right-of-use assets $ 501 Other assets Operating lease liabilities $ 501 Accounts payable and other liabilities Finance leases: Finance lease right-of-use assets $ 185 Finance lease accumulated amortization right-of-use assets (149 ) Property and equipment, net $ 36 Property and equipment, net Finance lease liabilities $ 78 Accounts payable and other liabilities

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2019
Subsequent Events [Abstract]
Subsequent Events	Note 11. Subsequent Events On July 30, 2019, the Company’s Board of Directors declared a quarterly cash dividend of $0.25 per share payable on September 20, 2019 to shareholders of record as of September 6, 2019. The Board considers the payment of a regular cash dividend each calendar quarter.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Adopted Accounting Guidance	Adopted Accounting Guidance In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The new guidance requires a lessee to recognize a lease liability and a right of use asset for all leases extending beyond twelve months. This standard was effective for us beginning in the first quarter of 2019. We elected the new transition method under the transition guidance within the new standard. Therefore, prior comparative periods are not adjusted. We also elected the package of practical expedients, which among other things, allows us to carryforward the historical lease classification. We made an accounting policy election not to recognize lease assets and lease liabilities for short-term operating leases. Adoption of the new guidance resulted in the Company recognizing right-of-use assets of $0.4 million and lease liabilities of $0.3 million. The cumulative effect adjustment to the opening balance of retained earnings was minimal. Adoption of this new guidance did not have a material effect on the Company’s consolidated financial statements as the Company does not have any significant leases.
Prospective Accounting Guidance	Prospective Accounting Guidance In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses. The current guidance delays the recognition of credit losses until a probable loss has occurred. The new guidance requires credit losses for securities measured at amortized cost to be determined using current expected credit loss estimates. These estimates are to be derived from historical, current and reasonable supporting forecasts, including prepayments and estimates, and will be recorded through a valuation account. The same method will be used for available-for-sale securities, but the valuation account will be limited to the amount by which the fair value is below amortized cost. The standard is effective for us in the first quarter of 2020. Implementation of the new guidance requires a modified retrospective approach without restatement, which means the first cumulative adjustment required will be a charge to retained earnings, with subsequent changes in the valuation account reported in the income statement. The financial statement impact will be determined by the nature of the portfolio held and the economic conditions at the time of implementation. The Company has formed an internal working group to evaluate the new standard and develop an implementation strategy. The group has researched data, developed models and methodologies and is working toward implementation. The Company will continue to monitor and evaluate the financial impact as the implementation date approaches. All other issued but not yet effective accounting and reporting standards as of June 30, 2019 are either not applicable to the Company or are not expected to have a material impact on the Company.

Fair Value Measurements (Polici

Fair Value Measurements (Policies)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	The Company carries available-for-sale securities at fair value in our consolidated financial statements and determines fair value measurements and disclosure in accordance with FASB ASC Topic 820, Fair Value Measurements and Disclosures. The Company determines the fair values of its financial instruments based on the fair value hierarchy established in ASC Topic 820, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard defines fair value, describes three levels of inputs that may be used to measure fair value, and expands disclosures about fair value measurements.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Earnings Per Share	The diluted EPS calculation includes potential common shares assumed issued under the treasury stock method, which reflects the potential dilution that would occur if any outstanding options were exercised or restricted stock becomes vested. Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 (in thousands, except share and per share amounts) Basic EPS Net income $ 17,890 $ 16,956 $ 37,290 $ 33,125 Basic weighted average common shares 19,245,592 19,208,601 19,237,401 19,197,925 Basic earnings per common share $ 0.93 $ 0.88 $ 1.94 $ 1.73 Diluted EPS Net income $ 17,890 $ 16,956 $ 37,290 $ 33,125 Diluted weighted average common shares: Weighted average common shares 19,245,592 19,208,601 19,237,401 19,197,925 Stock options and restricted stock 61,361 58,134 78,875 77,958 Diluted weighted average common shares 19,306,953 19,266,735 19,316,276 19,275,883 Diluted earnings per common share $ 0.93 $ 0.88 $ 1.93 $ 1.72

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2019
Gross Unrealized Gains and Losses and Amortized Cost and Fair Value of Investments Classified as Held-to-maturity	The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as held-to-maturity at June 30, 2019 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 439,103 $ 15,966 $ (36 ) $ 455,033 Corporate bonds 108,756 1,425 (17 ) 110,164 U.S. agency-based mortgage-backed securities 12,465 523 (12 ) 12,976 U.S. Treasury securities and obligations of U.S. government agencies 49,677 430 (29 ) 50,078 Asset-backed securities 949 10 (3 ) 956 Totals $ 610,950 $ 18,354 $ (97 ) $ 629,207 The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as held-to-maturity at December 31, 2018 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 445,922 $ 5,109 $ (2,084 ) $ 448,947 Corporate bonds 91,762 62 (455 ) 91,369 U.S. agency-based mortgage-backed securities 8,102 327 (80 ) 8,349 U.S. Treasury securities and obligations of U.S. government agencies 67,042 340 (339 ) 67,043 Asset-backed securities 1,050 22 (8 ) 1,064 Totals $ 613,878 $ 5,860 $ (2,966 ) $ 616,772
Gross Unrealized Gains and Losses and Cost or Amortized Cost and Fair Value of Investments Classified as Available-for-sale	The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as available-for-sale at June 30, 2019 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 220,385 $ 9,852 $ (15 ) $ 230,222 Corporate bonds 151,705 2,953 (39 ) 154,619 U.S. agency-based mortgage-backed securities 11,904 6 (58 ) 11,852 U.S. Treasury securities and obligations of U.S. government agencies 61,123 301 (224 ) 61,200 Totals $ 445,117 $ 13,112 $ (336 ) $ 457,893 The gross unrealized gains and losses on, and the amortized cost and fair value of, those investments classified as available-for-sale at December 31, 2018 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 231,848 $ 3,515 $ (2,118 ) $ 233,245 Corporate bonds 173,904 243 (933 ) 173,214 U.S. agency-based mortgage-backed securities 12,835 — (320 ) 12,515 U.S. Treasury securities and obligations of U.S. government agencies 61,185 — (1,429 ) 59,756 Totals $ 479,772 $ 3,758 $ (4,800 ) $ 478,730
Gross Unrealized Gains and Losses and Cost of Equity	The gross unrealized gains and losses on, and the cost of equity securities at June 30, 2019 are summarized as follows: Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Equity securities: Domestic common stock $ 22,582 $ 1,488 $ — $ 24,070 Total equity securities $ 22,582 $ 1,488 $ — $ 24,070 The gross unrealized gains and losses on, and the cost of equity securities at December 31, 2018 are summarized as follows: Cost Gross Gains Gross Losses Fair Value (in thousands) Equity securities: Domestic common stock $ 19,962 $ 30 $ (1,341 ) $ 18,651 Total equity securities $ 19,962 $ 30 $ (1,341 ) $ 18,651
Investment Securities Continuous Unrealized Loss Position	The following table summarizes the fair value and gross unrealized losses on securities, aggregated by major investment category and length of time that the individual securities have been in a continuous unrealized loss position: Less Than 12 Months 12 Months or Greater Total Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses (in thousands) June 30, 2019 Held-to-Maturity Fixed maturity securities: States and political subdivisions $ 6,038 $ 19 $ 11,835 $ 17 $ 17,873 $ 36 Corporate bonds — — 15,306 17 15,306 17 U.S. agency-based mortgage-backed securities — — 2,201 12 2,201 12 U.S. Treasury securities and obligations of U.S. government agencies — — 8,362 29 8,362 29 Asset-backed securities — — 177 3 177 3 Total held-to-maturity securities 6,038 19 37,881 78 43,919 97 Available-for-Sale Fixed maturity securities: States and political subdivisions $ — $ — $ 7,008 $ 15 $ 7,008 $ 15 Corporate bonds — — 22,346 39 22,346 39 U.S. agency-based mortgage-backed securities — — 10,588 58 10,588 58 U.S. Treasury securities and obligations of U.S. government agencies — — 39,120 224 39,120 224 Total available-for-sale securities — — 79,062 336 79,062 336 Total $ 6,038 $ 19 $ 116,943 $ 414 $ 122,981 $ 433 Less Than 12 Months 12 Months or Greater Total Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses Fair Value of Investments with Unrealized Losses Gross Unrealized Losses (in thousands) December 31, 2018 Held-to-Maturity Fixed maturity securities: States and political subdivisions $ 28,369 $ 59 $ 180,550 $ 2,025 $ 208,919 $ 2,084 Corporate bonds 17,448 36 48,315 419 65,763 455 U.S. agency-based mortgage-backed securities — — 2,287 80 2,287 80 U.S. Treasury securities and obligations of U.S. government agencies 2,865 4 46,486 335 49,351 339 Asset-backed securities — — 525 8 525 8 Total held-to-maturity securities 48,682 99 278,163 2,867 326,845 2,966 Available-for-Sale Fixed maturity securities: States and political subdivisions $ 16,109 $ 81 $ 76,255 $ 2,037 $ 92,364 $ 2,118 Corporate bonds 59,099 279 70,306 654 129,405 933 U.S. agency-based mortgage-backed securities — — 12,515 320 12,515 320 U.S. Treasury securities and obligations of U.S. government agencies — — 59,756 1,429 59,756 1,429 Total available-for-sale securities 75,208 360 218,832 4,440 294,040 4,800 Total $ 123,890 $ 459 $ 496,995 $ 7,307 $ 620,885 $ 7,766
Held-to-Maturity Securities [Member]
Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity	A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as held-to-maturity at June 30, 2019, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 79,934 $ 80,374 After one year through five years 216,626 220,476 After five years through ten years 84,179 87,047 After ten years 216,797 227,378 U.S. agency-based mortgage-backed securities 12,465 12,976 Asset-backed securities 949 956 Totals $ 610,950 $ 629,207
Available-for-Sale Securities [Member]
Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, by Contractual Maturity	A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as available-for-sale at June 30, 2019, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 49,966 $ 50,018 After one year through five years 158,125 159,944 After five years through ten years 46,069 47,983 After ten years 179,053 188,096 U.S. agency-based mortgage-backed securities 11,904 11,852 Totals $ 445,117 $ 457,893

Loss Reserves (Tables)

Loss Reserves (Tables)	6 Months Ended
	Jun. 30, 2019
Insurance [Abstract]
Liability for Unpaid Loss and Loss Adjustment Expenses, Net of Related Amounts Recoverable from Reinsurers	The following table provides the Company’s liability for unpaid loss and loss adjustment expenses, net of related amounts recoverable from reinsurers, for the six months ended June 30, 2019 and 2018: Six Months Ended June 30, 2019 2018 (in thousands) Balance, beginning of period $ 798,409 $ 771,845 Less amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 107,216 84,889 Net balance, beginning of period 691,193 686,956 Add incurred related to: Current accident year 121,727 126,060 Prior accident years (23,245 ) (20,822 ) Total incurred 98,482 105,238 Less paid related to: Current accident year 15,926 18,386 Prior accident years 77,362 84,194 Total paid 93,288 102,580 Net balance, end of period 696,387 689,614 Add amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 98,659 93,987 Balance, end of period $ 795,046 $ 783,601

Comprehensive Income and Accu_2

Comprehensive Income and Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Schedule of Changes in Accumulated Other Comprehensive Income (AOCI)	The following table illustrates the changes in the balance of each component of accumulated other comprehensive income for each period presented in the interim financial statements. Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 (in thousands) Beginning balance $ 4,962 $ (2,236 ) $ (832 ) $ 3,612 Other comprehensive income (loss) before reclassification 5,001 (449 ) 10,889 (5,863 ) Amounts reclassified from accumulated other comprehensive income (21 ) 602 83 168 Change in deferred tax valuation allowance 198 — — — Net current period other comprehensive income (loss) 5,178 153 10,972 (5,695 ) Ending balance $ 10,140 $ (2,083 ) $ 10,140 $ (2,083 )
Reclassification Out of Accumulated Other Comprehensive Income	The effects of reclassifications out of accumulated other comprehensive income by the respective line items of net income are presented in the following table. Component of Accumulated Other Three Months Ended Six Months Ended Affected line item in the Comprehensive Income June 30, June 30, statement of income 2019 2018 2019 2018 (in thousands) Unrealized gains (losses) on available-for-sale securities $ 26 $ (762 ) $ (105 ) $ (466 ) Net realized losses on investments 26 (762 ) (105 ) (466 ) Income before income taxes (5 ) 160 22 44 Income tax expense $ 21 $ (602 ) $ (83 ) $ (422 ) Net income

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Schedule of Assets Measured at Fair Value on Recurring Basis	At June 30, 2019, assets measu r June 30, 2019 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Financial instruments carried at fair value, classified as a part of: Securities available-for-sale—fixed maturity: States and political subdivisions $ — $ 230,222 $ — $ 230,222 Corporate bonds — 154,619 — 154,619 U.S. agency-based mortgage-backed securities — 11,852 — 11,852 U.S. Treasury securities 61,200 — — 61,200 Total securities available-for-sale—fixed maturity 61,200 396,693 — 457,893 Equity securities: Domestic common stock 24,070 — — 24,070 Total $ 85,270 $ 396,693 $ — $ 481,963 At December 31, 2018, assets measured at fair value on a recurring basis are summarized below: December 31, 2018 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Financial instruments carried at fair value, classified as part of: Securities available-for-sale—fixed maturity: States and political subdivisions $ — $ 233,245 $ — $ 233,245 Corporate bonds — 173,214 — 173,214 U.S. agency-based mortgage-backed securities — 12,515 — 12,515 U.S. Treasury securities and obligations of U.S. government agencies 59,756 — — 59,756 Total securities available-for-sale—fixed maturity $ 59,756 $ 418,974 $ — $ 478,730 Equity securities: Domestic common stock 18,651 — — 18,651 Total $ 78,407 $ 418,974 $ — $ 497,381
Schedule of Assets Measured at Amortized Cost	At June 30, 2019, assets measured at amortized cost are summarized below: June 30, 2019 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Securities held-to-maturity—fixed maturity: States and political subdivisions $ — $ 455,033 $ — $ 455,033 Corporate bonds — 110,164 — 110,164 U.S. agency-based mortgage-backed securities — 12,976 — 12,976 U.S. Treasury securities 7,882 — — 7,882 Obligations of U.S. government agencies — 42,196 — 42,196 Asset-backed securities — 956 — 956 Total held-to-maturity $ 7,882 $ 621,325 $ — $ 629,207 At December 31, 2018, assets measured at amortized cost are summarized below: December 31, 2018 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Securities held-to-maturity—fixed maturity: States and political subdivisions $ — $ 448,947 $ — $ 448,947 Corporate bonds — 91,369 — 91,369 U.S. agency-based mortgage-backed securities — 8,349 — 8,349 U.S. Treasury securities 7,111 — — 7,111 Obligations of U.S. government agencies — 59,932 — 59,932 Asset-backed securities — 1,064 — 1,064 Total held-to-maturity $ 7,111 $ 609,661 $ — $ 616,772
Summary of Carrying Values and Corresponding Fair Values for Financial Instruments	The following table summarizes the carrying values and corresponding fair values for financial instruments: As of June 30, 2019 As of December 31, 2018 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Assets: Fixed maturity securities—held-to-maturity $ 610,950 $ 629,207 $ 613,878 $ 616,772 Fixed maturity securities—available-for-sale 457,893 457,893 478,730 478,730 Equity securities 24,070 24,070 18,651 18,651 Short-term investments 70,146 70,146 14,231 14,231 Cash and cash equivalents 51,246 51,246 40,344 40,344

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Schedule of Supplemental Balance Sheet Information Related to Leases	Supplemental balance sheet information related to leases is as follows: June 30, 2019 Balance Sheet Classification (in thousands) Operating leases: Operating lease right-of-use assets $ 501 Other assets Operating lease liabilities $ 501 Accounts payable and other liabilities Finance leases: Finance lease right-of-use assets $ 185 Finance lease accumulated amortization right-of-use assets (149 ) Property and equipment, net $ 36 Property and equipment, net Finance lease liabilities $ 78 Accounts payable and other liabilities

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Percentage of comparable consolidated amounts	95.00%	95.00%
Right-of-use assets	$ 501
Operating lease liabilities	$ 501
ASU 2016-02 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Right-of-use assets			$ 400
Operating lease liabilities			$ 300

Stock Options and Restricted _2

Stock Options and Restricted Stock - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)shares	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)Incentive_Planshares	Jun. 30, 2018USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans | Incentive_Plan			2
Market value of shares issued | $			$ 1,400	$ 500
Stock options exercised, Shares			5,000	15,000
Proceeds from stock option exercises | $			$ 20	$ 67
Share-based compensation expense | $	$ (100)	$ 800	$ 500	$ 800
Restricted Stock [Member] | Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			9,000
Restricted Stock [Member] | Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			4,890	5,761
Performance Awards [Member] | Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock issued, shares			9,391	3,304
2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	0		0
2005 Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding	0		0

Earnings Per Share - Calculatio

Earnings Per Share - Calculation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share Basic [Abstract]
Net income	$ 17,890	$ 16,956	$ 37,290	$ 33,125
Basic weighted average common shares	19,245,592	19,208,601	19,237,401	19,197,925
Basic earnings per common share	$ 0.93	$ 0.88	$ 1.94	$ 1.73
Net income	$ 17,890	$ 16,956	$ 37,290	$ 33,125
Weighted average common shares	19,245,592	19,208,601	19,237,401	19,197,925
Stock options and restricted stock	61,361	58,134	78,875	77,958
Diluted weighted average common shares	19,306,953	19,266,735	19,316,276	19,275,883
Diluted earnings per common share	$ 0.93	$ 0.88	$ 1.93	$ 1.72

Investments - Gross Unrealized

Investments - Gross Unrealized Gains and Losses and Amortized Cost and Fair Value of Investments Classified as Held-to-Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	$ 610,950	$ 613,878
Held-to-Maturity, Gross Unrealized Gains	18,354	5,860
Held-to-Maturity, Gross Unrealized Losses	(97)	(2,966)
Held-to-Maturity, Fair Value	629,207	616,772
States and Political Subdivisions [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	439,103	445,922
Held-to-Maturity, Gross Unrealized Gains	15,966	5,109
Held-to-Maturity, Gross Unrealized Losses	(36)	(2,084)
Held-to-Maturity, Fair Value	455,033	448,947
Corporate Bonds [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	108,756	91,762
Held-to-Maturity, Gross Unrealized Gains	1,425	62
Held-to-Maturity, Gross Unrealized Losses	(17)	(455)
Held-to-Maturity, Fair Value	110,164	91,369
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	12,465	8,102
Held-to-Maturity, Gross Unrealized Gains	523	327
Held-to-Maturity, Gross Unrealized Losses	(12)	(80)
Held-to-Maturity, Fair Value	12,976	8,349
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	49,677	67,042
Held-to-Maturity, Gross Unrealized Gains	430	340
Held-to-Maturity, Gross Unrealized Losses	(29)	(339)
Held-to-Maturity, Fair Value	50,078	67,043
Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	949	1,050
Held-to-Maturity, Gross Unrealized Gains	10	22
Held-to-Maturity, Gross Unrealized Losses	(3)	(8)
Held-to-Maturity, Fair Value	$ 956	$ 1,064

Investments - Gross Unrealize_2

Investments - Gross Unrealized Gains and Losses and Cost or Amortized Cost and Fair Value of Investments Classified as Available-for-Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Totals, Amortized Cost	$ 445,117	$ 479,772
Totals, Gross Unrealized Gains	13,112	3,758
Totals, Gross Unrealized Losses	(336)	(4,800)
Totals, Fair Value	457,893	478,730
States and Political Subdivisions [Member]
Investment [Line Items]
Totals, Amortized Cost	220,385	231,848
Totals, Gross Unrealized Gains	9,852	3,515
Totals, Gross Unrealized Losses	(15)	(2,118)
Totals, Fair Value	230,222	233,245
Corporate Bonds [Member]
Investment [Line Items]
Totals, Amortized Cost	151,705	173,904
Totals, Gross Unrealized Gains	2,953	243
Totals, Gross Unrealized Losses	(39)	(933)
Totals, Fair Value	154,619	173,214
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Totals, Amortized Cost	11,904	12,835
Totals, Gross Unrealized Gains	6
Totals, Gross Unrealized Losses	(58)	(320)
Totals, Fair Value	11,852	12,515
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Totals, Amortized Cost	61,123	61,185
Totals, Gross Unrealized Gains	301
Totals, Gross Unrealized Losses	(224)	(1,429)
Totals, Fair Value	$ 61,200	$ 59,756

Investments - Gross Unrealize_3

Investments - Gross Unrealized Gains and Losses and Cost of Equity (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Equity securities, Cost	$ 22,582	$ 19,962
Equity securities, Gross Unrealized Gains	1,488	30
Equity securities, Gross Unrealized Losses		(1,341)
Equity securities, Fair Value	24,070	18,651
Domestic Common Stock [Member]
Investment [Line Items]
Equity securities, Cost	22,582	19,962
Equity securities, Gross Unrealized Gains	1,488	30
Equity securities, Gross Unrealized Losses		(1,341)
Equity securities, Fair Value	$ 24,070	$ 18,651

Investments - Summary of Amorti

Investments - Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, Classified as Held-to-Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Within one year, Amortized Cost	$ 79,934
After one year through five years, Amortized Cost	216,626
After five years through ten years, Amortized Cost	84,179
After ten years, Amortized Cost	216,797
Held-to-maturity, Amortized Cost, Totals	610,950	$ 613,878
Within one year, Fair Value	80,374
After one year through five years, Fair Value	220,476
After five years through ten years, Fair Value	87,047
After ten years, Fair Value	227,378
Held-to-maturity, Fair Value, Totals	629,207	616,772
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost	12,465
Held-to-maturity, Amortized Cost, Totals	12,465	8,102
Held-to-maturity, Fair Value	12,976
Held-to-maturity, Fair Value, Totals	12,976	8,349
Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost	949
Held-to-maturity, Amortized Cost, Totals	949	1,050
Held-to-maturity, Fair Value	956
Held-to-maturity, Fair Value, Totals	$ 956	$ 1,064

Investments - Summary of Amor_2

Investments - Summary of Amortized Cost and Fair Value of Investments in Fixed Maturity Securities, Classified as Available-for-Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Within one year, Amortized Cost	$ 49,966
After one year through five years, Amortized Cost	158,125
After five years through ten years, Amortized Cost	46,069
After ten years, Amortized Cost	179,053
Totals, Amortized Cost	445,117	$ 479,772
Within one year, Fair Value	50,018
After one year through five years, Fair Value	159,944
After five years through ten years, Fair Value	47,983
After ten years, Fair Value	188,096
Total, Fair Value	457,893	478,730
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Available-for-sale securities, Amortized Cost	11,904
Totals, Amortized Cost	11,904	12,835
Available-for-sale securities, Fair value	11,852
Total, Fair Value	$ 11,852	$ 12,515

Investments - Investment Securi

Investments - Investment Securities Continuous Unrealized Loss Position (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months	$ 6,038	$ 48,682
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months	19	99
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	37,881	278,163
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	78	2,867
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	43,919	326,845
Held-to-maturity securities, Gross Unrealized Losses, Total	97	2,966
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months		75,208
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months		360
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	79,062	218,832
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	336	4,440
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	79,062	294,040
Available-for Sale, Gross Unrealized Losses, Total	336	4,800
Fair Value of Investments with Unrealized Losses, Less Than 12 months	6,038	123,890
Gross Unrealized Loss, Less Than 12 Months	19	459
Fair Value of Investments with Unrealized Losses, 12 Months or Greater	116,943	496,995
Gross Unrealized Losses, 12 Months or Greater	414	7,307
Fair Value of Investments with Unrealized Losses, Total	122,981	620,885
Gross Unrealized Losses, Total	433	7,766
States and Political Subdivisions [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months	6,038	28,369
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months	19	59
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	11,835	180,550
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	17	2,025
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	17,873	208,919
Held-to-maturity securities, Gross Unrealized Losses, Total	36	2,084
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months		16,109
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months		81
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	7,008	76,255
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	15	2,037
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	7,008	92,364
Available-for Sale, Gross Unrealized Losses, Total	15	2,118
Corporate Bonds [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months		17,448
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months		36
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	15,306	48,315
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	17	419
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	15,306	65,763
Held-to-maturity securities, Gross Unrealized Losses, Total	17	455
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months		59,099
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months		279
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	22,346	70,306
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	39	654
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	22,346	129,405
Available-for Sale, Gross Unrealized Losses, Total	39	933
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	2,201	2,287
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	12	80
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	2,201	2,287
Held-to-maturity securities, Gross Unrealized Losses, Total	12	80
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	10,588	12,515
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	58	320
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	10,588	12,515
Available-for Sale, Gross Unrealized Losses, Total	58	320
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months		2,865
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months		4
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	8,362	46,486
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	29	335
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	8,362	49,351
Held-to-maturity securities, Gross Unrealized Losses, Total	29	339
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	39,120	59,756
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	224	1,429
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	39,120	59,756
Available-for Sale, Gross Unrealized Losses, Total	224	1,429
Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	177	525
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	3	8
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	177	525
Held-to-maturity securities, Gross Unrealized Losses, Total	$ 3	$ 8

Investments - Additional Inform

Investments - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)Security	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)Security	Jun. 30, 2018USD ($)
Investments Schedule [Abstract]
Individual fixed maturity held in unrealized loss position | Security	66		66
Individual fixed maturity held in unrealized loss position longer than 12 months | Security	61		61
Net unrealized gains (losses) on equity securities	$ 642,000	$ 76,000	$ 2,800,000	$ (314,000)
Impairment losses recognized	0	0	$ 0	0
Net realized losses from call of fixed maturity securities	$ 100,000
Net realized losses on sale of fixed maturity securities classified as available-for-sale		$ 1,100,000		$ 1,100,000

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Valuation allowance	$ 200,000
Company recognized uncertain tax positions	$ 0	$ 0

Loss Reserves - Liability for U

Loss Reserves - Liability for Unpaid Loss and Loss Adjustment Expenses, Net of Related Amounts Recoverable from Reinsurers (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Roll Forward In Liability For Unpaid Claims And Claims Adjustment Expense [Abstract]
Balance, beginning of period	$ 798,409	$ 771,845
Less amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses	107,216	84,889
Net balance, beginning of period	691,193	686,956
Add incurred related to:
Current accident year	121,727	126,060
Prior accident years	(23,245)	(20,822)
Total incurred	98,482	105,238
Less paid related to:
Current accident year	15,926	18,386
Prior accident years	77,362	84,194
Total paid	93,288	102,580
Net balance, end of period	696,387	689,614
Add amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses	98,659	93,987
Balance, end of period	$ 795,046	$ 783,601

Loss Reserves - Additional Info

Loss Reserves - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Insurance [Abstract]
Loss and LAE Related to Prior Periods	$ 23,245	$ 20,822

Comprehensive Income and Accu_3

Comprehensive Income and Accumulated Other Comprehensive Income - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]
Comprehensive income	$ 23,068	$ 17,109	$ 48,262	$ 27,430
Comprehensive income tax rate			21.00%	21.00%

Comprehensive Income and Accu_4

Comprehensive Income and Accumulated Other Comprehensive Income - Schedule of Changes in Accumulated Other Comprehensive Income (AOCI) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 430,405	$ 432,068	$ 409,762	$ 425,423
Change in deferred tax valuation allowance	198
Ending Balance	449,443	445,391	449,443	445,391
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	4,962	(2,236)	(832)	3,612
Other comprehensive income (loss) before reclassification	5,001	(449)	10,889	(5,863)
Amounts reclassified from accumulated other comprehensive income	(21)	602	83	168
Change in deferred tax valuation allowance	198
Net current period other comprehensive income (loss)	5,178	153	10,972	(5,695)
Ending Balance	$ 10,140	$ (2,083)	$ 10,140	$ (2,083)

Comprehensive Income and Accu_5

Comprehensive Income and Accumulated Other Comprehensive Income - Reclassification Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net realized losses on investments	$ (82)	$ (1,111)	$ (23)	$ (1,142)
Income before income taxes	22,169	20,930	45,978	40,344
Income tax expense	(4,279)	(3,974)	(8,688)	(7,219)
Net income	17,890	16,956	37,290	33,125
Unrealized Gains (losses) on Available-for-Sale Securities [Member] | Reclassification Out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net realized losses on investments	26	(762)	(105)	(466)
Income before income taxes	26	(762)	(105)	(466)
Income tax expense	(5)	160	22	44
Net income	$ 21	$ (602)	$ (83)	$ (422)

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	$ 457,893	$ 478,730
Equity securities, Fair Value	24,070	18,651
Fair Value, Measurements, Recurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	457,893	478,730
Total	481,963	497,381
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	61,200	59,756
Total	85,270	78,407
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	396,693	418,974
Total	396,693	418,974
Fair Value, Measurements, Recurring [Member] | States and Political Subdivisions [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	230,222	233,245
Fair Value, Measurements, Recurring [Member] | States and Political Subdivisions [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	230,222	233,245
Fair Value, Measurements, Recurring [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	154,619	173,214
Fair Value, Measurements, Recurring [Member] | Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	154,619	173,214
Fair Value, Measurements, Recurring [Member] | U.S. Agency-Based Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	11,852	12,515
Fair Value, Measurements, Recurring [Member] | U.S. Agency-Based Mortgage-Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	11,852	12,515
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	61,200	59,756
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	61,200	59,756
Fair Value, Measurements, Recurring [Member] | Common Stock [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities, Fair Value	24,070	18,651
Fair Value, Measurements, Recurring [Member] | Common Stock [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities, Fair Value	$ 24,070	$ 18,651

Fair Value Measurements - Sch_2

Fair Value Measurements - Schedule of Assets Measured at Amortized Cost (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	$ 629,207	$ 616,772
States and Political Subdivisions [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	455,033	448,947
Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	110,164	91,369
U.S. Agency-Based Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	12,976	8,349
U.S. Treasury Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	7,882	7,111
Obligations of U.S. Government Agencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	42,196	59,932
Asset-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	956	1,064
Fair Value, Inputs, Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	7,882	7,111
Fair Value, Inputs, Level 1 [Member] | U.S. Treasury Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	7,882	7,111
Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	621,325	609,661
Fair Value, Inputs, Level 2 [Member] | States and Political Subdivisions [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	455,033	448,947
Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	110,164	91,369
Fair Value, Inputs, Level 2 [Member] | U.S. Agency-Based Mortgage-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	12,976	8,349
Fair Value, Inputs, Level 2 [Member] | Obligations of U.S. Government Agencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	42,196	59,932
Fair Value, Inputs, Level 2 [Member] | Asset-Backed Securities [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	$ 956	$ 1,064

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Carrying Values and Corresponding Fair Values for Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities—held to maturity	$ 610,950	$ 613,878
Fixed maturity securities—held to maturity	629,207	616,772
Fixed maturity securities—available-for-sale	457,893	478,730
Equity securities	24,070	18,651
Short-term investments	70,146	14,231
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities—held to maturity	629,207	616,772
Fixed maturity securities—available-for-sale	457,893	478,730
Equity securities	24,070	18,651
Short-term investments	70,146	14,231
Cash and cash equivalents	51,246	40,344
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities—available-for-sale	457,893	478,730
Equity securities	24,070	18,651
Short-term investments	70,146	14,231
Cash and cash equivalents	$ 51,246	$ 40,344

Treasury Stock - Additional Inf

Treasury Stock - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Oct. 31, 2016
Equity [Abstract]
Share repurchase program, new limit amount			$ 25,000,000
Shares repurchased under the program	0	0

Leases - Additional Information

Leases - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2019
Lessee Lease Description [Line Items]
Operating lease, existence of option to extend	true
Finance lease, existence of option to extend	true
Minimum [Member]
Lessee Lease Description [Line Items]
Operating lease, remaining lease term	2 months
Finance lease, remaining lease term	2 months
Maximum [Member]
Lessee Lease Description [Line Items]
Operating lease, remaining lease term	55 months
Finance lease, remaining lease term	55 months
Operating lease, options to extend lease term	5 years
Finance lease, options to extend lease term	5 years

Leases - Schedule of Supplement

Leases - Schedule of Supplemental Balance Sheet Information Related to Leases (Detail) $ in Thousands	Jun. 30, 2019USD ($)
Leases [Abstract]
Operating lease right-of-use assets	$ 501
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssets
Operating lease liabilities	$ 501
Operating Lease, Liability, Statement of Financial Position [Extensible List]	amsf:AccountsPayableAndOtherLiabilities
Finance lease right-of-use assets	$ 185
Finance lease accumulated amortization right-of-use assets	(149)
Property and equipment, net	$ 36
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentNet
Finance lease liabilities	$ 78
Finance Lease, Liability, Statement of Financial Position [Extensible List]	amsf:AccountsPayableAndOtherLiabilities

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - Dividend Declared [Member]	Jul. 30, 2019$ / shares
Subsequent Event [Line Items]
Cash dividend per share	$ 0.25
Date of payment for dividend	Sep. 20, 2019
Date of record for dividend payment	Sep. 6, 2019