AMERISAFE (AMSF) 10-K 28 Feb 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Feb. 15, 2019	Jun. 30, 2018
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Trading Symbol	AMSF
Entity Registrant Name	AMERISAFE INC
Entity Central Index Key	1,018,979
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		19,269,980
Entity Public Float			$ 1,102.3

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investments:
Fixed maturity securities—held-to-maturity, at amortized cost (fair value $616,772 and $639,309 in 2018 and 2017, respectively)	$ 613,878	$ 629,668
Fixed maturity securities—available-for-sale, at fair value (cost $479,772 and $461,236 in 2018 and 2017, respectively)	478,730	465,594
Equity securities, at fair value (cost $19,962 and $8,503 in 2018 and 2017, respectively)	18,651	9,282
Short-term investments	14,231	25,770
Total investments	1,125,490	1,130,314
Cash and cash equivalents	40,344	55,559
Amounts recoverable from reinsurers	112,006	90,133
Premiums receivable, net of allowance	162,478	174,234
Deferred income taxes	21,852	19,262
Accrued interest receivable	10,197	10,635
Property and equipment, net	6,258	6,128
Deferred policy acquisition costs	19,734	20,251
Federal income tax recoverable		1,761
Other assets	17,572	9,959
Total assets	1,515,931	1,518,236
Liabilities:
Reserves for loss and loss adjustment expenses	798,409	771,845
Unearned premiums	149,296	157,270
Amounts held for others	41,388	36,908
Policyholder deposits	46,795	48,364
Insurance-related assessments	28,258	28,246
Federal income tax payable	3,412
Accounts payable and other liabilities	38,611	37,076
Payable for investments purchased		13,104
Total liabilities	1,106,169	1,092,813
Shareholders’ equity:
Common stock: voting—$0.01 par value authorized shares—50,000,000 in 2018 and 2017; 20,528,230 and 20,504,165 shares issued and 19,269,980 and 19,245,915 shares outstanding in 2018 and 2017, respectively	205	204
Additional paid-in capital	211,431	210,081
Treasury stock, at cost (1,258,250 shares in 2018 and 2017)	(22,370)	(22,370)
Accumulated earnings	221,328	233,896
Accumulated other comprehensive income (loss), net	(832)	3,612
Total shareholders’ equity	409,762	425,423
Total liabilities and shareholders’ equity	$ 1,515,931	$ 1,518,236

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Fixed maturity securities, fair value	$ 616,772	$ 639,309
Fixed maturity securities, cost	479,772	461,236
Equity securities, cost	$ 19,962	$ 8,503
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	20,528,230	20,504,165
Common stock, shares outstanding	19,269,980	19,245,915
Treasury stock, shares	1,258,250	1,258,250

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues
Net premiums earned	$ 350,326	$ 346,156	$ 368,704
Net investment income	30,452	29,281	28,106
Net realized losses on investments	(1,536)	(647)	(494)
Net unrealized losses on equity securities	(2,088)
Fee and other income	599	418	346
Total revenues	377,753	375,208	396,662
Expenses
Loss and loss adjustment expenses incurred	204,891	209,324	199,031
Underwriting and certain other operating costs	28,981	28,333	29,470
Commissions	26,160	24,812	26,243
Salaries and benefits	25,992	25,631	24,881
Policyholder dividends	4,148	4,868	4,216
Total expenses	290,172	292,968	283,841
Income before income taxes	87,581	82,240	112,821
Income tax expense	15,949	36,009	34,956
Net income	$ 71,632	$ 46,231	$ 77,865
Earnings per share
Basic	$ 3.73	$ 2.41	$ 4.08
Diluted	$ 3.71	$ 2.40	$ 4.05
Shares used in computing earnings per share
Basic	19,208,978	19,165,489	19,105,806
Diluted	19,293,082	19,245,866	19,203,650
Extraordinary cash dividends declared per common share	$ 3.50	$ 3.50	$ 3.25
Cash dividends declared per common share	$ 0.88	$ 0.80	$ 0.72

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 18,806	$ 19,701	$ 16,956	$ 16,169	$ 649	$ 16,577	$ 15,481	$ 13,524	$ 71,632	$ 46,231	$ 77,865
Other comprehensive income:
Unrealized gain (loss) on securities, net of tax									(4,243)	4,104	(3,079)
Comprehensive income	$ 22,176	$ 17,582	$ 17,109	$ 10,321	$ 1,228	$ 17,194	$ 17,437	$ 14,476	$ 67,389	$ 50,335	$ 74,786

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - 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, 2015	$ 453,981	$ 203	$ 204,688	$ (22,370)	$ 268,873	$ 2,587
Beginning Balance, Shares at Dec. 31, 2015		20,388,396
Treasury Stock Beginning Balance, Shares at Dec. 31, 2015				(1,258,250)
Comprehensive income:
Net income	77,865				77,865
Other comprehensive income:
Change in unrealized gains loss, net of tax	(3,079)					(3,079)
Comprehensive income	74,786
Common stock issued upon exercise of options	837	$ 1	836
Common stock issued upon exercise of options, Shares		68,879
Common stock issued	603		603
Common stock issued, Shares		31,110
Share-based compensation	1,268		1,268
Tax benefit from share-based payments	995		995
Dividends to shareholders	(76,320)				(76,320)
Ending Balance at Dec. 31, 2016	456,150	$ 204	208,390	$ (22,370)	270,418	(492)
Ending Balance, Shares at Dec. 31, 2016		20,488,385
Treasury Stock Ending Balance, Shares at Dec. 31, 2016				(1,258,250)
Comprehensive income:
Net income	46,231				46,231
Other comprehensive income:
Change in unrealized gains loss, net of tax	4,104					4,104
Comprehensive income	50,335
Common stock issued	396		396
Common stock issued, Shares		15,780
Share-based compensation	1,295		1,295
Dividends to shareholders	(82,753)				(82,753)
Ending Balance at Dec. 31, 2017	$ 425,423	$ 204	210,081	$ (22,370)	233,896	3,612
Ending Balance, Shares at Dec. 31, 2017	20,504,165	20,504,165
Treasury Stock Ending Balance, Shares at Dec. 31, 2017	(1,258,250)			(1,258,250)
Comprehensive income:
Impact of adoption of ASU | ASU 2016-01 [Member]					615	(615)
Impact of adoption of ASU | ASU 2018-02 [Member]					(414)	414
Net income	$ 71,632				71,632
Other comprehensive income:
Change in unrealized gains loss, net of tax	(4,243)					(4,243)
Comprehensive income	67,389
Common stock issued upon exercise of options	67		67
Common stock issued upon exercise of options, Shares		15,000
Common stock issued	196	$ 1	195
Common stock issued, Shares		9,065
Share-based compensation	1,088		1,088
Dividends to shareholders	(84,401)				(84,401)
Ending Balance at Dec. 31, 2018	$ 409,762	$ 205	$ 211,431	$ (22,370)	$ 221,328	$ (832)
Ending Balance, Shares at Dec. 31, 2018	20,528,230	20,528,230
Treasury Stock Ending Balance, Shares at Dec. 31, 2018	(1,258,250)			(1,258,250)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities
Net income	$ 71,632	$ 46,231	$ 77,865
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	996	984	1,181
Net amortization of investments	10,787	14,015	16,247
Deferred income taxes	(1,462)	12,800	(2,249)
Net realized losses on investments	1,536	647	509
Net unrealized losses on equity securities	2,088
Net realized losses on disposal of assets		2	1
Share-based compensation	2,065	2,018	1,603
Changes in operating assets and liabilities:
Premiums receivable, net	11,756	8,771	2,359
Accrued interest receivable	438	725	325
Deferred policy acquisition costs	517	(951)	1,112
Amounts held by others	(7,855)	27,848	1,016
Other assets	1,873	(1,882)	1,631
Reserves for loss and loss adjustment expenses	26,564	29,069	24,743
Unearned premiums	(7,974)	(4,758)	(5,955)
Reinsurance balances	(21,873)	(6,495)	7,285
Amounts held for others and policyholder deposits	2,911	4,168	(17,066)
Accounts payable and other liabilities	4,269	(2,382)	3,605
Net cash provided by operating activities	98,268	130,810	114,212
Investing activities
Purchases of investments held-to-maturity	(99,330)	(222,104)	(102,830)
Purchases of investments available-for-sale	(124,128)	(108,517)	(216,466)
Purchases of equity securities	(11,459)	(8,503)
Purchases of short-term investments	(133,355)	(62,687)	(35,295)
Proceeds from maturities of investments held-to-maturity	99,984	152,995	177,159
Proceeds from sales and maturities of investments available-for-sale	100,357	112,179	115,552
Proceeds from sales of equity securities	3	1
Proceeds from sales and maturities of short-term investments	139,865	72,400	13,040
Proceeds from redemptions of other investments	130	13,172
Purchases of property and equipment	(1,126)	(478)	(1,638)
Net cash used in investing activities	(29,059)	(51,542)	(50,478)
Financing activities
Proceeds from stock option exercises	67		837
Tax benefit from share-based payments			995
Dividends to shareholders	(84,491)	(82,645)	(76,111)
Net cash used in financing activities	(84,424)	(82,645)	(74,279)
Change in cash and cash equivalents	(15,215)	(3,377)	(10,545)
Cash and cash equivalents at beginning of year	55,559	58,936	69,481
Cash and cash equivalents at end of year	40,344	55,559	58,936
Supplemental disclosure of cash flow information
Income taxes paid	$ 11,235	$ 28,255	$ 31,500

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies Organization AMERISAFE, Inc. is an insurance holding company incorporated in the state of Texas. The accompanying 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, agriculture, maritime, and oil and gas. Assets and revenues of AIIC and its subsidiaries represent at least 95% of comparable consolidated amounts of the Company for each of 2018, 2017 and 2016. Basis of Presentation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Adopted Accounting Guidance In January 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-01, Financial Instruments – Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. This guidance requires fair value measurement for equity investments (not including those that result in consolidation of the investee or use the equity method of accounting) and the recognition of changes in fair value to be presented as a component of net income. The guidance also revises the disclosure requirements related to fair value changes of liabilities presented in comprehensive income, eliminates disclosure related to the methods and assumptions underlying fair value for financial instruments measured at amortized cost, and simplifies impairment assessments for equity investments without readily determinable fair values. The adoption of this new guidance in the first quarter of 2018 resulted in an immaterial decrease in net income of $390 thousand or a $0.02 decrease to our diluted earnings per common share. At December 31, 2017, equity investments were classified as available-for-sale on the Company’s balance sheet. However, upon adoption, the updated guidance eliminated the available-for-sale balance sheet classification for equity investments. In May 2014, the FASB issued ASU 2014-09 (Topic 606): Revenue from Contract s In February 2018, the FASB issued ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220). This ASU provided new guidance on reclassification from Other Comprehensive Income (“OCI”) of tax effects related to the recently passed tax reform legislation (the “Tax Act”). The guidance gives entities the option to reclassify to retained earnings tax effects related to items in accumulated OCI deemed to be stranded as a result of tax reform. The guidance was effective for us in the first quarter of 2018 and was applied retrospectively. The Company’s policy for releasing income tax effects from accumulated OCI was the individual securities approach for available-for-sale securities. The adoption of this guidance did not have a material impact on our financial condition and results of operations. In December 2017, the SEC issued Staff Accounting Bulletin (SAB) 118 which provided guidance on accounting for tax effects of the Tax Act. Among many changes of the Tax Act which affected Property and Casualty Insurers, the Tax Act required property and casualty taxpayers to discount loss reserves based solely on IRS factors and no longer by reference to historical payment patterns. In December 2018, the IRS released its guidance for determining the Tax Act transition adjustment along with its 2018 loss reserves discounting factors. The Company has completed its analysis for the tax effects relating to the Tax Act. During the period ended December 31, 2018, the Company recognized an increase in the deferred tax balance of $1.5 million to the provisional amounts recorded at December 31, 2017. Prospective Accounting Guidance In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). Under current guidance for lessees, leases are only included on the balance sheet if certain criteria, classifying the contract as a capital lease, are met. The new guidance requires a lessee to recognize a lease liability and a right of use asset for all leases extending beyond twelve months. The new guidance is effective for us in the first quarter of 2019. We will elect the new transition method under the transition guidance within the new standard which means prior comparative periods will not be adjusted. We will also elect the package of practical expedients, which among other things, allows us to carryforward the historical lease classification. We will make an accounting policy election not to recognize lease assets and lease liabilities for short-term operating leases. Adoption of the guidance is not expected to have a material effect on the Company’s consolidated financial statements as the Company does not have any significant leases. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses. The new guidance replaces the methodology of credit loss impairment, which currently, delays the recognition of credit losses until a probable loss has been incurred. 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 allowance account that will run through the income statement. The same method will be used for available-for-sale securities, but the valuation allowance 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. The Company will continue to monitor and evaluate the impact as the implementation date approaches. All other issued but not yet effective accounting and reporting standards as of December 31, 2018 are either not applicable to the Company or are not expected to have a material impact on the Company. Investments The Company has the ability and positive intent to hold certain investments until maturity. Therefore, fixed maturity securities classified as held-to-maturity are recorded at amortized cost. Fixed maturity securities classified as available-for-sale are recorded at fair value. Temporary changes in the fair value of these securities are reported in shareholders’ equity as a component of other comprehensive income, net of deferred income taxes. Changes in the fair value of equity securities are recorded in net income. 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. The Company regularly reviews the fair value of its investments. Impairment of an investment security results in a reduction of the carrying value of the security and the realization of a loss when the fair value of the security declines below the cost or amortized cost, as applicable, for the security and the impairment is deemed to be other-than-temporary. The Company regularly reviews its investment portfolio to evaluate the existence of other-than-temporary declines in the fair value of investments. The Company considers various factors in determining if a decline in the fair value of an individual security is other-than-temporary, including but not limited to a reduction or interruption in scheduled cash flows, the financial condition of the issuer, how long and by how much the fair value has been below amortized cost, losses due to credit concerns, downgrades and the Company’s intent to sell or ability to hold the security. Impairment losses on fixed maturities are recognized in the financial statements depending on the facts and circumstances related to the specific security. If we intend to sell a security or it is more likely than not that we would be required to sell a security before the recovery of its amortized cost, less any current period credit loss, an other-than-temporary impairment would be recognized in net income for the difference between amortized cost and fair value. If we do not expect to recover the amortized cost basis, we do not plan to sell the security and if it is not more likely than not that we would be required to sell a security before the recovery of its amortized cost, less any current period credit loss, the recognition of the other-than-temporary impairment is bifurcated. The credit loss portion would be recognized in net income and the noncredit loss portion in other comprehensive income. Cash and Cash Equivalents Cash equivalents include short-term money market funds with an original maturity of 90 days or less. Short-Term Investments Short-term investments include municipal securities and corporate bonds with an original maturity greater than 90 days but less than one year. Other Investments Other investments consisted of a limited partnership interest that was accounted for under the equity method, valued using the net asset value provided by the general partner of the limited partnership, which approximates the fair value of the interest. The limited partnership’s objective was to generate absolute returns by investing long and short in publicly-traded global securities. The investment in the limited partnership was fully redeemed during 2017. The Company has no unfunded commitments to the limited partnership. Premiums Receivable Premiums receivable consist primarily of premium-related balances due from policyholders. The Company considers premiums receivable as past due based on the payment terms of the underlying policy. The balance is shown net of the allowance for doubtful accounts. Receivables due from insureds are charged off when a determination has been made by management that a specific balance will not be collected. An estimate of amounts that are likely to be charged off is established as an allowance for doubtful accounts as of the balance sheet date. The estimate is primarily comprised of specific balances that are considered probable to be charged off after all collection efforts have ceased, as well as historical trends and an analysis of the aging of the receivables. Property and Equipment The Company’s property and equipment, including certain costs incurred to develop or obtain software for internal use, are stated at cost less accumulated depreciation. Depreciation is calculated primarily by the straight-line method over the estimated useful lives of the respective assets, generally 39 years for buildings and three to seven years for all other fixed assets. Deferred Policy Acquisition Costs The direct costs of successfully acquiring and renewing business are capitalized to the extent recoverable and are amortized over the effective period of the related insurance policies in proportion to premium revenue earned. These capitalized costs consist mainly of sales commissions, premium taxes and other underwriting costs. The Company evaluates deferred policy acquisition costs for recoverability by comparing the unearned premiums to the estimated total expected claim costs and related expenses, offset by anticipated investment income. The Company would reduce the deferred costs if the unearned premiums were less than expected claims and expenses after considering investment income, and report any adjustments in amortization of deferred policy acquisition costs. There were no adjustments necessary in 2018, 2017 or 2016. Reserves for Loss and Loss Adjustment Expenses Reserves for loss and loss adjustment expenses represent the estimated ultimate cost of all reported and unreported losses incurred through December 31. The Company does not discount loss and loss adjustment expense reserves. 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 and adjusted as necessary as experience develops or new information becomes known. Any such adjustments are included in income from current operations. Subrogation recoverables, as well as deductible recoverables from policyholders, are estimated using individual case-basis valuations and aggregate estimates. Deductibles that are recoverable from policyholders and other recoverables from state funds decrease the liability for loss and loss adjustment expenses. The Company funds its obligations under certain settled claims where the payment pattern and ultimate cost are fixed and determinable on an individual claim basis through the purchase of annuities. These annuities are purchased from unaffiliated carriers and name the claimant as payee. The cost of purchasing the annuity is recorded as paid loss and loss adjustment expenses. To the extent the annuity funds estimated future claims, reserves for loss and loss adjustment expense are reduced. Premium Revenue Premiums on workers’ compensation insurance are based on actual payroll costs or production during the policy term and are normally billed monthly in arrears or annually. However, the Company generally requires a deposit at the inception of a policy. Premium revenue is earned on a pro rata basis over periods covered by the policies. The reserve for unearned premiums on these policies is computed on a daily pro rata basis. The Company estimates the annual premiums to be paid by its policyholders when the Company issues the policies and records those amounts on the balance sheet as premiums receivable. The Company conducts premium audits on all of its voluntary business policyholders annually, upon the expiration of each policy, including when the policy is renewed. The purpose of these audits is to verify that policyholders have accurately reported their payroll expenses and employee job classifications, and therefore have paid the Company the premium required under the terms of the policies. The difference between the estimated premium and the ultimate premium is referred to as “earned but unbilled” premium, or EBUB premium. EBUB premium can be higher or lower than the estimated premium. EBUB premium is subject to significant variability and can either increase or decrease earned premium based upon several factors, including changes in premium growth, industry mix and economic conditions. Due to the timing of audits and other adjustments, ultimate premium earned is generally not determined for several months after the expiration of the policy. The Company estimates EBUB premiums on a quarterly basis using historical data and applying various assumptions based on the current market and economic conditions, and records an adjustment to premium, related losses, and expenses as warranted. Reinsurance Reinsurance premiums, losses and allocated loss adjustment expenses are accounted for on a basis consistent with those used in accounting for the original policies issued and the terms of the reinsurance contracts. Amounts recoverable from reinsurers include balances currently owed to the Company for losses and allocated loss adjustment expenses that have been paid to policyholders, amounts that are currently reserved for and will be recoverable once the related expense has been paid and experience-rated commissions recoverable upon commutation. Upon management’s determination that an amount due from a reinsurer is uncollectible due to the reinsurer’s insolvency or other matters, the amount is written off. Ceding commissions are earned from certain reinsurance companies and are intended to reimburse the Company for policy acquisition costs related to those premiums ceded to the reinsurers. Ceding commission income is recognized over the effective period of the related insurance policies in proportion to premium revenue earned and is reflected as a reduction in underwriting and certain other operating costs. Experience-rated commissions are earned from certain reinsurance companies based on the financial results of the applicable risks ceded to the reinsurers. These commission revenues on reinsurance contracts are recognized during the related reinsurance treaty period and are based on the same assumptions used for recording loss and allocated loss adjustment expenses. These commissions are reflected as a reduction in underwriting and certain other operating costs and are adjusted as necessary as experience develops or new information becomes known. Any such adjustments are included in income from current operations. Experience-rated commissions increased underwriting and certain other operating costs by $0.2 million in 2018 and 2017 and had minimal impact in 2016. In December 2016, the Company commuted reinsurance agreements with Hannover Reinsurance Limited (Ireland) (“Hannover”) and Tokio Millennium Re Limited (“Tokio”) covering portions of accident years 2011 through 2013. The Company received cash of $0.2 million and an additional $25.4 million payment effectuated solely through offset against the balance of the funds withheld account under the reinsurance agreements in exchange for releasing Hannover and Tokio from their reinsurance obligations under the commuted agreements. Both Hannover and Tokio remain obligated to the subsidiaries of the Company under other reinsurance agreements. As a result of the commutation, the effect on the Company’s net income in the year ended December 31, 2016 was immaterial. Fee and Other Income The Company recognizes income related to commissions earned by AGAI as the related services are performed. Advertising All advertising expenditures incurred by the Company are charged to expense in the period to which they relate and are included in underwriting and certain other operating costs in the consolidated statements of income. Total advertising expenses incurred were $0.5 million in 2018 and 2017, and $0.7 million in 2016. Income Taxes The Company accounts for income taxes using the liability method. The provision for income taxes has two components, amounts currently payable or receivable and deferred amounts. Deferred income tax assets and liabilities are recognized for the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred income tax assets and liabilities are measured using tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred income tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company considers deferred tax assets to be recoverable if it is probable that the related tax losses can be offset by future taxable income. The Company includes reversal of existing temporary differences, tax planning strategies available and future operating income in this assessment. To the extent the deferred tax assets exceed the amount expected to be recovered in future years, the Company records a valuation allowance for the amount determined unrecoverable. Insurance-Related Assessments Insurance-related assessments are accrued in the period in which they have been incurred. The Company is subject to a variety of assessments related to insurance commerce, including those by state guaranty funds and workers’ compensation second-injury funds. State guaranty fund assessments are used by state insurance oversight agencies to cover losses of policyholders of insolvent or rehabilitated insurance companies and for the operating expenses of such agencies. Assessments based on premiums are generally paid one year after the calendar year in which the premium is written, while assessments based on losses are generally paid within one year of the calendar year in which the loss is paid. Policyholder Dividends The Company writes certain policies for which the policyholder may participate in favorable claims experience through a dividend. An estimated provision for workers’ compensation policyholders’ dividends is accrued as the related premiums are earned. Dividends do not become a fixed liability unless and until declared by the respective Boards of Directors of AMERISAFE’s insurance subsidiaries. The dividend to which a policyholder may be entitled is set forth in the policy and is related to the amount of losses sustained under the policy. Dividends are calculated after the policy expiration. The Company is able to estimate the policyholder dividend liability because the Company has information regarding the underlying loss experience of the policies written with dividend provisions and can estimate future dividend payments from the policy terms. Earnings Per Share The Company computes earnings per share (EPS) in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 260, Earnings Per Share. Basic EPS is calculated by dividing income available to common shareholders 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 or warrants were exercised or restricted stock becomes vested. Share-Based Compensation The Company recognizes the impact of its share-based compensation in accordance with FASB ASC Topic 718, Compensation-Stock Compensation.

Investments

Investments	12 Months Ended
	Dec. 31, 2018
Investments Debt And Equity Securities [Abstract]
Investments	2. Investments Short-term investments held at December 31, 2018 include $ 13.4 million of corporate bonds and $0.8 million of obligations of states and political subdivisions. Short-term investments held at December 31, 2017 include $25.8 million of U.S. Treasury securities and obligations of U.S. government agencies. In 2017, AMERISAFE redeemed an investment in a limited partnership hedge fund accounted for under the equity method. 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 Unrealized Gains Gross Unrealized 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 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, 2017 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 460,428 $ 9,628 $ (955 ) $ 469,101 Corporate bonds 100,024 190 (167 ) 100,047 U.S. agency-based mortgage-backed securities 10,260 625 (40 ) 10,845 U.S. Treasury securities and obligations of U.S. government agencies 57,657 548 (198 ) 58,007 Asset-backed securities 1,299 25 (15 ) 1,309 Totals $ 629,668 $ 11,016 $ (1,375 ) $ 639,309 The gross unrealized gains and losses on, and the cost or amortized cost and fair value of, those investments classified as available-for-sale at December 31, 2017 are summarized as follows: Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Fixed maturity: States and political subdivisions $ 244,898 $ 6,819 $ (577 ) $ 251,140 Corporate bonds 130,210 224 (212 ) 130,222 U.S. agency-based mortgage-backed securities 18,813 — (799 ) 18,014 U.S. Treasury securities and obligations of U.S. government agencies 67,315 29 (1,126 ) 66,218 Total fixed maturity 461,236 7,072 (2,714 ) 465,594 Equity securities 8,503 779 — 9,282 Totals $ 469,739 $ 7,851 $ (2,714 ) $ 474,876 A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as held-to-maturity at December 31, 2018, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 76,875 $ 76,861 After one year through five years 256,614 257,530 After five years through ten years 81,311 81,755 After ten years 189,926 191,213 U.S. agency-based mortgage-backed securities 8,102 8,349 Asset-backed securities 1,050 1,064 Totals $ 613,878 $ 616,772 A summary of the amortized cost and fair value of investments in fixed maturity securities, classified as available-for-sale at December 31, 2018, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 61,650 $ 61,435 After one year through five years 175,743 174,213 After five years through ten years 47,058 46,725 After ten years 182,486 183,842 U.S. agency-based mortgage-backed securities 12,835 12,515 Totals $ 479,772 $ 478,730 Actual maturities may differ from contractual maturities because certain borrowers have the right to call or prepay certain obligations with or without call or prepayment penalties. At December 31, 2018, there were $16.1 million of held-to-maturity investments and $2.5 million of available-for-sale investments on deposit with regulatory agencies of states in which the Company does business. A summary of the Company’s realized gains and losses on sales, calls or redemptions of investments for 2018, 2017 and 2016 is as follows: Fixed Maturity Securities Available for Sale Equity Securities Other Total (in thousands) Year ended December 31, 2018 Proceeds from sales $ 15,025 $ 3 $ — $ 15,028 Gross realized investment gains $ 238 $ 1 $ — $ 239 Gross realized investment losses (1,354 ) — — (1,354 ) Net realized investment gains (losses) (1,116 ) 1 — (1,115 ) Other, including losses on calls and redemptions (144 ) — (277 ) (421 ) Net realized gains (losses) on investments $ (1,260 ) $ 1 $ (277 ) $ (1,536 ) Year ended December 31, 2017 Proceeds from sales $ 14,591 $ 1 $ 13,172 $ 27,764 Gross realized investment gains $ 485 $ 1 $ — $ 486 Gross realized investment losses (5 ) — — (5 ) Net realized investment gains 480 1 — 481 Other, including losses on calls and redemptions (520 ) — (608 ) (1,128 ) Net realized gains (losses) on investments $ (40 ) $ 1 $ (608 ) $ (647 ) Year ended December 31, 2016 Proceeds from sales $ 54,730 $ — $ 4,609 $ 59,339 Gross realized investment gains $ 823 $ — $ 68 $ 891 Gross realized investment losses (1,728 ) — — (1,728 ) Net realized investment gains (losses) (905 ) — 68 (837 ) Other, including gains on calls and redemptions 274 — 69 343 Net realized gains (losses) on investments $ (631 ) $ — $ 137 $ (494 ) In 2016, the Company sold $3.0 million in bonds that were classified as held-to-maturity. In January 2016, Moody’s downgraded the bonds to B2 from B1 citing increasing liquidity concerns and also placed the bonds on negative outlook indicating the rating could be downgraded further. Given the evidence of significant credit deterioration, the Company elected to sell the bonds for $3.0 million, recognizing a $0.1 million realized gain. Major categories of the Company’s net investment income are summarized as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Gross investment income: Fixed maturity securities $ 28,762 $ 28,961 $ 27,837 Equity securities 448 201 — Short-term investments and cash and cash equivalents 2,208 1,117 348 Other investments — 104 1,568 Total gross investment income 31,418 30,383 29,753 Investment expenses (966 ) (1,102 ) (1,647 ) Net investment income $ 30,452 $ 29,281 $ 28,106 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) 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 December 31, 2017 Held-to-Maturity Fixed maturity securities: States and political subdivisions $ 110,698 $ 654 $ 19,895 $ 301 $ 130,593 $ 955 Corporate bonds 56,425 156 4,121 11 60,546 167 U.S. agency-based mortgage-backed securities 2,798 40 — — 2,798 40 U.S. Treasury securities and obligations of U.S. government agencies 48,153 122 3,948 76 52,101 198 Asset-backed securities — — 967 15 967 15 Total held-to-maturity securities 218,074 972 28,931 403 247,005 1,375 Available-for-Sale Fixed maturity securities: States and political subdivisions $ 23,365 $ 86 $ 19,153 $ 491 $ 42,518 $ 577 Corporate bonds 82,795 171 5,888 41 88,683 212 U.S. agency-based mortgage-backed securities 14,686 59 3,328 740 18,014 799 U.S. Treasury securities and obligations of U.S. government agencies 14,730 204 47,716 922 62,446 1,126 Total available-for-sale securities 135,576 520 76,085 2,194 211,661 2,714 Total $ 353,650 $ 1,492 $ 105,016 $ 2,597 $ 458,666 $ 4,089 At December 31, 2018, the Company held 398 individual fixed maturity securities that were in an unrealized loss position, of which 323 were in a continuous unrealized loss position for longer than 12 months. The Company regularly reviews its investment portfolio to evaluate the necessity of recording impairment losses for other-than-temporary declines in the fair value of our investments. The Company considers various factors in determining if a decline in the fair value of an individual security is other-than-temporary. The key factors considered 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 forced 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. The Company 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. In 2018, 2017 and 2016, there were no impairment losses recognized for other-than-temporary declines in the fair value of our investments.

Premiums Receivable

Premiums Receivable	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Premiums Receivable	3. Premiums Receivable Premiums receivable consist primarily of premium-related balances due from policyholders. The balance is shown net of the allowance for doubtful accounts. The components of premiums receivable are shown below: December 31, 2018 2017 (in thousands) Premiums receivable $ 167,868 $ 179,460 Allowance for doubtful accounts (5,390 ) (5,226 ) Premiums receivable, net $ 162,478 $ 174,234 The following summarizes the activity in the allowance for doubtful accounts: December 31, 2018 2017 2016 (in thousands) Balance, beginning of year $ 5,226 $ 5,212 $ 4,852 Provision for bad debts 883 1,394 1,646 Write-offs (719 ) (1,380 ) (1,286 ) Balance, end of year $ 5,390 $ 5,226 $ 5,212 Included in premiums receivable at December 31, 2018, 2017 and 2016 is the Company’s estimate for EBUB premium of $7.5 million, $6.3 million and $7.7 million, respectively.

Deferred Policy Acquisition Cos

Deferred Policy Acquisition Costs	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Deferred Policy Acquisition Costs	4. Deferred Policy Acquisition Costs Deferred policy acquisition costs represent those costs that are incremental and directly related to the successful acquisition of new or the renewal of existing insurance policies. We defer incremental costs that result directly from, and are essential to, the acquisition or renewal of an insurance policy. We also defer a portion of employee total compensation costs directly related to time spent performing specific acquisition or renewal activities. These costs are deferred and expensed over the life of the related policies. Major categories of the Company’s deferred policy acquisition costs are summarized as follows: December 31, 2018 2017 (in thousands) Agents’ commissions $ 14,953 $ 15,238 Premium taxes 3,161 3,395 Deferred underwriting expenses 1,620 1,618 Total deferred policy acquisition costs $ 19,734 $ 20,251 The following summarizes the activity in the deferred policy acquisition costs: Year Ended December 31, 2018 2017 2016 (in thousands) Balance, beginning of year $ 20,251 $ 19,300 $ 20,412 Policy acquisition costs deferred 45,252 43,960 43,209 Amortization expense during the year (45,769 ) (43,009 ) (44,321 ) Balance, end of year $ 19,734 $ 20,251 $ 19,300

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2018
Property Plant And Equipment [Abstract]
Property and Equipment	5. Property and Equipment Property and equipment consist of the following: December 31, 2018 2017 (in thousands) Land and office building $ 7,798 $ 7,713 Furniture and equipment 6,150 6,578 Software 7,339 6,856 Automobiles 74 74 21,361 21,221 Accumulated depreciation (15,103 ) (15,093 ) Property and equipment, net $ 6,258 $ 6,128 Furniture and equipment included property held under capital leases of $0.2 million at December 31, 2018. Accumulated depreciation includes $120,000 that is related to these properties at December 31, 2018. Furniture and equipment included property held under capital leases of $0.2 million at December 31, 2017. Accumulated depreciation includes $58,000 that is related to these properties at December 31, 2017. Furniture and equipment included property held under capital leases of $0.2 million at December 31, 2016. Accumulated depreciation includes $80,000 that is related to these properties at December 31, 2016. The capital lease obligations related to these properties are included in accounts payable and other liabilities. Future minimum lease payments related to the capital lease obligations are detailed below (in thousands): 2019 $ 47 2020 48 2021 4 Present value of net minimum lease payments $ 99

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Reinsurance	6. Reinsurance The Company cedes certain premiums and losses to various reinsurers under excess-of-loss treaties. These reinsurance arrangements provide for greater diversification of business, allow management to control exposure to potential losses arising from large risks, and provide additional capacity for growth. Ceded reinsurance contracts do not relieve the Company from its obligations to policyholders. The Company remains liable to its policyholders for the portion reinsured to the extent that any reinsurer does not meet the obligations assumed under the reinsurance agreements. To minimize its exposure to significant losses from reinsurer insolvencies, the Company evaluates the financial condition of its reinsurers and monitors concentrations of credit risk arising from similar geographic regions, activities, or economic characteristics of the reinsurers on a continual basis. The effect of reinsurance on premiums written and earned in 2018, 2017 and 2016 was as follows: 2018 Premiums 2017 Premiums 2016 Premiums Written Earned Written Earned Written Earned (in thousands) Gross $ 351,696 $ 359,670 $ 350,267 $ 355,025 $ 373,055 $ 379,011 Ceded (9,344 ) (9,344 ) (8,869 ) (8,869 ) (10,307 ) (10,307 ) Net premiums $ 342,352 $ 350,326 $ 341,398 $ 346,156 $ 362,748 $ 368,704 The amounts recoverable from reinsurers consist of the following: December 31, 2018 2017 (in thousands) Unpaid losses recoverable: Case basis $ 76,525 $ 66,061 Incurred but not reported 30,691 18,828 Paid losses recoverable 325 554 Experience-rated commissions recoverable 4,465 4,690 Total $ 112,006 $ 90,133 Amounts recoverable from reinsurers consists of ceded case reserves, ceded incurred but not reported (“IBNR”) reserves, paid losses recoverable and experience-rated commissions recoverable. Ceded case and ceded IBNR reserves represent the portion of gross loss and loss adjustment expense liabilities that are recoverable under reinsurance agreements, but are not yet due from reinsurers. Paid losses recoverable are receivables currently due from reinsurers for ceded paid losses. The Company considers paid losses recoverable outstanding for more than 90 days to be past due. At December 31, 2018, there were no paid losses recoverable past due. The Company received reinsurance recoveries of $1.3 million in 2018, $1.6 The Company generally secures large reinsurance recoverable balances with various forms of collateral, including funds withheld accounts, irrevocable letters of credit and secured trusts. At December 31, 2018, reinsurance recoverables from reinsurers that exceeded 1.5% of statutory surplus of the Company’s insurance subsidiaries are shown below (in thousands). Reinsurer A.M. Best Rating Amounts Recoverable as of December 31, 2018 (in thousands) Hannover Reinsurance (Ireland) Limited (1) A+ $ 53,609 Allianz Risk Transfer AG (Bermuda) (1) A+ 13,084 Odyssey America Reinsurance Corporation A 11,754 Minnesota Workers’ Compensation Reinsurance Association (1) NR 8,823 Other reinsurers 24,736 Total amounts recoverable from reinsurers 112,006 Funds withheld and letters of credit related to the above recoverables (69,932 ) Total unsecured amounts recoverable from reinsurers $ 42,074 (1) Current participant in our 2019 reinsurance program.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	7. Income Taxes The Company’s deferred income tax assets and liabilities are as follows: December 31, 2018 2017 (in thousands) Deferred income tax assets: Discounting of net unpaid loss and loss adjustment expenses $ 21,377 $ 8,830 Unearned premiums 8,069 8,466 Accrued expenses and other 2,636 2,359 State income tax 855 782 Accrued policyholder dividends 2,188 1,918 Impaired securities 21 42 Capital loss carryforward — 190 Accrued insurance-related assessments 3,139 3,256 Net unrealized loss on securities 496 — Total deferred tax assets 38,781 25,843 Deferred income tax liabilities: Deferred policy acquisition costs (5,207 ) (5,317 ) Callable bond amortization (5 ) (8 ) Unrealized gain on securities available-for-sale — (1,070 ) Property and equipment and other (178 ) (3 ) Salvage and subrogation (719 ) (183 ) Loss reserves adjustment due to the Tax Act (10,820 ) — Total deferred income tax liabilities (16,929 ) (6,581 ) Net deferred income taxes $ 21,852 $ 19,262 The components of consolidated income tax expense (benefit) are as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Current: Federal $ 16,407 $ 22,477 $ 35,602 State 1,004 732 1,603 17,411 23,209 37,205 Deferred: Federal (1,389 ) 12,965 (2,120 ) State (73 ) (165 ) (129 ) (1,462 ) 12,800 (2,249 ) Total $ 15,949 $ 36,009 $ 34,956 During 2018, 2017 and 2016, there was no valuation allowance on the Company’s deferred income tax assets and liabilities. Income tax expense from operations is different from the amount computed by applying the U.S. federal income tax statutory rate of 21% in 2018 and 35% in 2017 and 2016 to income before income taxes as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Income tax computed at federal statutory tax rate $ 18,392 $ 28,784 $ 39,487 Tax-exempt interest, net (2,965 ) (5,707 ) (5,370 ) State income tax 720 311 913 Dividends received deduction (44 ) (48 ) (125 ) Revaluation of net deferred income tax assets — 12,620 — Other (154 ) 49 51 $ 15,949 $ 36,009 $ 34,956 On December 22, 2017, the Tax Act was signed into law making significant changes to the Internal Revenue Code. Changes include, but are not limited to, a corporate tax rate decrease from 35% to 21% effective for tax years beginning after December 31, 2017. As a result, we recorded $12.6 million as additional income tax expense related to our net deferred tax assets revalued at the new lower rate of 21% in the fourth quarter of 2017, the period in which the legislation was enacted. In December 2018, the IRS released its guidance for determining the Tax Act transition adjustment related to the discounting of loss reserves. During the period ended December 31, 2018, the Company recorded an increase in its deferred tax assets and a corresponding increase in its deferred tax liabilities as a result of the transition adjustment, which had no impact on tax expense recognized in 2018. As of December 31, 2018, we have completed our accounting for the tax effects of enactment of the Tax Act. The Company recognizes interest and penalties related to uncertain tax positions in income tax expense. There were no uncertain tax positions as of December 31, 2018, 2017 and 2016. Tax years 2015 through 2018 are subject to examination by the federal and state taxing authorities.

Line of Credit

Line of Credit	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Line of Credit	8. Line of Credit The Company has an agreement providing for a line of credit in the maximum amount of $20.0 million with Frost Bank. The agreement expires in December 2019. Under the agreement, advances may be made either in the form of loans or letters of credit. Borrowings under the agreement accrue at interest rates based upon prime rate or LIBOR. Under the agreement, the Company pays a fee of 0.25% on the unused portion of the loan in arrears quarterly, or a fee of $50,000 annually, assuming the line of credit is not used during the calendar year. The line of credit is unsecured. No borrowings or letters of credit were outstanding under the line of credit arrangement at December 31, 2018 or 2017.

Loss and Loss Adjustment Expens

Loss and Loss Adjustment Expenses	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Loss and Loss Adjustment Expenses	9. Loss and Loss Adjustment Expenses The following development tables provide the incurred and paid claims and allocated claim adjustment expenses, net of reinsurance, for workers’ compensation and general liability for accident years 2009 through 2018. The incurred but not reported (“IBNR”) claims and claims frequency is included for each accident year presented. Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance As of For the Years Ended December 31, December 31, 2018 (Dollars in thousands) Total IBNR Plus Expected Cumulative Development Number of Accident Unaudited (1) on Reported Claims Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Claims Reported 2009 $ 185,359 $ 188,746 $ 188,462 $ 187,943 $ 184,006 $ 182,274 $ 177,795 $ 176,586 $ 177,015 $ 174,731 $ 3,407 5,372 2010 — 179,156 202,479 208,035 205,769 198,861 193,029 191,000 189,403 189,040 5,612 5,970 2011 — — 196,384 199,522 199,163 198,213 195,262 192,988 191,126 189,327 7,045 6,043 2012 — — — 222,549 222,075 212,738 193,515 184,460 182,859 180,387 7,454 5,749 2013 — — — — 241,810 241,811 233,656 220,457 214,701 210,588 10,210 5,763 2014 — — — — — 268,846 268,846 249,097 235,058 226,933 12,576 5,833 2015 — — — — — — 262,573 262,573 252,514 235,471 22,038 5,510 2016 — — — — — — — 250,491 250,491 241,406 19,874 5,378 2017 — — — — — — — — 244,094 244,098 9,887 5,178 2018 — — — — — — — — — 250,487 15,423 5,186 Total $ 2,142,468 $ 113,526 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, (Dollars in thousands) Accident Unaudited (1) Claim Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Frequency (2) 2009 $ 42,332 $ 96,173 $ 123,946 $ 142,667 $ 150,925 $ 155,365 $ 158,214 $ 159,345 $ 160,580 $ 162,253 19.82 2010 — 47,520 108,714 141,029 156,974 165,834 169,565 172,426 175,019 176,663 24.93 2011 — — 53,329 111,029 140,831 153,968 161,639 165,967 167,757 169,994 22.81 2012 — — — 50,579 107,467 133,658 149,161 154,553 157,207 159,807 18.73 2013 — — — — 51,396 119,507 150,304 165,994 172,479 177,724 16.54 2014 — — — — — 53,060 119,820 153,320 169,736 180,683 14.97 2015 — — — — — — 54,141 121,599 151,818 170,461 14.23 2016 — — — — — — — 52,238 115,713 143,016 14.19 2017 — — — — — — — — 56,951 122,552 14.58 2018 — — — — — — — — — 62,061 14.42 Total 1,525,214 All outstanding claim liabilities before 2008, net of reinsurance 73,939 Liabilities for claims and claim adjustment expenses, net of reinsurance 691,193 (1) Data presented for these calendar years is required supplementary information, which is unaudited. (2) Frequency, as calculated above, refers to reported claims divided by gross premium earned. The average annual percentage payout of incurred claims by age, net of reinsurance, for workers’ compensation and general liability as of December 31, 2018 is summarized below. Since workers’ compensation has long payout periods, the table below shows less than 100% in the years disclosed. This is required supplementary information, which is unaudited. Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Unaudited) Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9 Year 10 24.6% 29.9% 14.6% 8.2% 4.1% 2.2% 1.4% 1.1% 0.8% 1.0% The following table provides a reconciliation of the beginning and ending reserve balances, net of related amounts recoverable from reinsurers, for 2018, 2017 and 2016: Year Ended December 31, 2018 2017 2016 (in thousands) Balance, beginning of period $ 771,845 $ 742,776 $ 718,033 Less amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 84,889 78,256 64,858 Net balance, beginning of period 686,956 664,520 653,175 Add incurred related to: Current accident year 250,487 244,094 250,337 Prior accident years (45,596 ) (34,770 ) (51,306 ) Total incurred 204,891 209,324 199,031 Less paid related to: Current accident year 62,061 56,951 52,085 Prior accident years 138,593 129,937 135,601 Total paid 200,654 186,888 187,686 Net balance, end of period 691,193 686,956 664,520 Add amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 107,216 84,889 78,256 Balance, end of period $ 798,409 $ 771,845 $ 742,776 The foregoing reconciliation reflects favorable development of the net reserves at December 31, 2018, 2017 and 2016. The favorable development reduced loss and loss adjustment expenses incurred by $45.6 million in 2018, driven primarily by accident years 2014, 2015 and 2016 of $8.1 million, $17.0 million and $9.1 million, respectively. In 2017 and 2016, the Company recorded favorable development of $34.8 million and $51.3 million, 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. Reserves established for workers’ compensation insurance have included the exposure to occupational disease or accidents related to asbestos or environmental claims. The exposure to asbestos claims emanate from the direct sale of workers’ compensation insurance. These claims resulted from industry workers who were exposed to tremolite asbestos dust and electricians and carpenters who were exposed to products that contained asbestos. There has been no known exposure to asbestos claims arising from assumed business. The emergence of these claims is slow and highly unpredictable. The Company estimates full impact of the asbestos exposure by establishing full case basis reserves on all known losses. Reserves for losses incurred but not reported (IBNR) include a provision for development of reserves on reported losses. Reserves are established for loss adjustment expenses (LAE) associated with these case and IBNR loss reserves. The following table details our exposures to various asbestos related claims: Year Ended December 31, 2018 2017 2016 (in thousands) Reserves for loss and LAE at beginning of year $ 1,748 $ 1,487 $ 958 Incurred losses and LAE during the current year 108 556 816 Loss and LAE payments (301 ) (295 ) (287 ) Reserves for loss and LAE at end of year $ 1,555 $ 1,748 $ 1,487 The Company has historically written general liability coverages that are reported in other liability lines of business. These coverages may be associated with the property and casualty industry’s exposure to environmental claims. However, the Company has not been notified by any insured for which exposure exists due to these types of claims. Company management believes potential exposure to environmental claims to be remote. Therefore, the Company has no loss or loss adjustment expense reserves for such liabilities. The anticipated effect of inflation is implicitly considered when estimating liabilities for loss and loss adjustment expenses. Average severities are projected based on historical trends adjusted for implemented changes in underwriting standards, policy provisions and general economic trends. These anticipated trends are monitored based on actual development and are modified if necessary.

Statutory Accounting and Regula

Statutory Accounting and Regulatory Requirements	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Statutory Accounting and Regulatory Requirements	10. Statutory Accounting and Regulatory Requirements The Company’s insurance subsidiaries file financial statements prepared in accordance with statutory accounting principles prescribed or permitted by the insurance regulatory authorities of the states in which the subsidiaries are domiciled. Statutory-basis shareholders’ capital and surplus at December 31, 2018, 2017 and 2016 of the directly owned insurance subsidiary, AIIC, and the combined statutory-basis net income and realized investment gains for all AMERISAFE’s insurance subsidiaries for the three years in the period ended December 31, 2018, were as follows (in thousands): 2018 2017 2016 Capital and surplus $ 383,575 $ 382,062 $ 394,016 Net income 72,979 61,628 79,858 Net realized losses on investments (1,536 ) (647 ) (504 ) Property and casualty insurance companies are subject to certain risk-based capital requirements, or RBC requirements, specified by the National Association of Insurance Commissioners. Under these requirements, a target minimum amount of capital and surplus maintained by a property/casualty insurance company is determined based on the various risk factors related to it. At December 31, 2018, the capital and surplus of AIIC and its subsidiaries exceeded the minimum RBC requirement. Pursuant to regulatory requirements, AIIC cannot pay dividends to the Company in excess of the greater of 10% of statutory surplus, or statutory net income, excluding realized investment gains, for the preceding 12-month period, without the prior approval of the Nebraska Director of Insurance. However, for purposes of this dividend calculation, net income from the previous two calendar years may be carried forward to the extent that it has not already been paid out as dividends. AIIC paid $65.4 million in dividends to the Company in 2018, $78.9 million in 2017 and $67.0 million in 2016. Based upon the dividend limitation described above, AIIC could pay to the Company dividends of up to $71.0 million in 2019 without seeking regulatory approval.

Capital Stock

Capital Stock	12 Months Ended
	Dec. 31, 2018
Equity [Abstract]
Capital Stock	11. Capital Stock Common Stock The Company is authorized to issue 50,000,000 shares of common stock, par value $0.01 per share. At December 31, 2018, there were 20,528,230 shares of common stock issued and 19,269,980 shares outstanding. Preferred Stock The Company is authorized to issue 10,000,000 shares of preferred stock, par value $0.01 per share. At December 31, 2018, there were no shares of preferred stock outstanding.

Stock Options and Restricted St

Stock Options and Restricted Stock	12 Months Ended
	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Options and Restricted Stock	12. Stock Options and Restricted Stock 2005 Incentive Plan The AMERISAFE 2005 Equity Incentive Plan (the “2005 Incentive Plan”) is administered by the Compensation Committee of the Board and was designed to provide incentive compensation to executive officers and other key management personnel. The 2005 Incentive Plan permitted awards in the form of incentive stock options, as defined in Section 422(b) of the Internal Revenue Code of 1986, non-qualified stock options, restricted shares of common stock and restricted stock units. In connection with the approval of the 2012 Equity and Incentive Compensation Plan by the Company’s shareholders, no further grants will be made under the 2005 Incentive Plan. All grants made under the 2005 Incentive plan will continue in effect, subject to the terms and conditions of the 2005 Incentive Plan. Stock options granted under the 2005 Incentive Plan are exercisable, subject to vesting requirements determined by the Compensation Committee, for periods of up to ten years from the date of grant. Stock options generally expire 90 days after the cessation of an optionee’s service as an employee. However, in the case of an optionee’s death or disability, the unexercised portion of a stock option remains exercisable for up to one year after the optionee’s death or disability. Stock options granted under the 2005 Incentive Plan are not transferable, except by will or the laws of descent and distribution. The Company uses the Black-Scholes-Merton option pricing model to estimate the fair value of each option on the date of grant. The expected terms of options are developed by considering the Company’s historical attrition rate for those employees at the officer level, who are eligible to receive options. Further, the Company aggregates individual awards into homogenous groups based upon grant date. Expected volatility is estimated using daily historical volatility for six companies within the property and casualty insurance sector. The Company believes that historical volatility of this peer group is currently the best estimate of expected volatility of the market price of the Company’s common shares. The dividend yield was assumed to be zero as the Company did not pay cash dividends until 2013. The risk-free interest rate is the yield on the grant date of U.S. Treasury zero coupon securities with a maturity comparable to the expected term of the options. The following table summarizes information about the stock option activity under the 2005 Incentive Plan: Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Life (in years) Outstanding at January 1, 2016 88,879 12.10 4.3 Granted — — — Exercised (68,879 ) 12.14 3.3 Canceled, forfeited, or expired — — — Outstanding at December 31, 2016 20,000 8.71 3.1 Exercisable at December 31, 2016 20,000 8.71 3.1 Outstanding at January 1, 2017 20,000 8.71 3.1 Granted — — — Exercised — — — Canceled, forfeited, or expired — — — Outstanding at December 31, 2017 20,000 5.21 2.1 Exercisable at December 31, 2017 20,000 5.21 2.1 Outstanding at January 1, 2018 20,000 5.21 2.1 Granted — — — Exercised (15,000 ) 4.46 0.9 Canceled, forfeited, or expired — — — Outstanding at December 31, 2018 5,000 3.95 1.9 Exercisable at December 31, 2018 5,000 3.95 1.9 2018 2017 2016 (in thousands) Cash received from option exercises $ 67 $ — $ 837 Total tax benefits realized for tax deductions from options exercised — — 833 Total intrinsic value of options exercised 766 — 2,967 Grant date fair value of options vested — — — Aggregate intrinsic value of vested options outstanding 264 1,128 1,073 The following table summarizes information about the restricted stock activity under the 2005 Incentive Plan: Shares Weighted- Average Grant- Date Fair Value per Share Nonvested balance at January 1, 2016 1,600 27.35 Granted — — Vested (800 ) 27.35 Forfeited — — Nonvested balance at December 31, 2016 800 27.35 Granted — — Vested (800 ) 27.35 Forfeited — — Nonvested balance at December 31, 2017 — — Granted — — Vested — — Forfeited — — Nonvested balance at December 31, 2018 — — The Company recognized compensation expense of $12,000 in 2018 and $56,000 in 2017 and $58,000 in 2016, related to awards made under the 2005 Incentive Plan. There were no tax benefits realized for tax deductions from vesting of restricted stock in 2018 and 2017. Tax benefits realized for tax deductions from vesting of restricted stock in 2016 were $110,000. 2012 Equity and Incentive Compensation Plan In 2012, the Company’s shareholders approved the AMERISAFE 2012 Equity and Incentive Compensation Plan (the “2012 Incentive Plan”). The 2012 Incentive Plan is administered by the Compensation Committee of the Board and is designed to attract, retain and motivate non-employee directors, officers, key employees and consultants by providing incentives for superior performance. The 2012 Incentive Plan authorizes the grant of equity-based compensation in the form of option rights, appreciation rights, restricted shares, restricted stock units, cash incentive awards, performance shares and units, and other types of awards. A maximum of 500,000 shares of common stock may be issued or transferred upon the exercise of option rights or appreciation rights, as restricted shares and released from substantial risk of forfeiture, in payment of restricted stock units, in payment of performance shares or performance units that have been earned, as awards of shares of common stock, as other awards granted under the 2012 Incentive Plan, or in payment of dividend equivalents paid with respect to awards made under the plan subject to adjustment in the event of a merger, stock dividend, stock split or similar event, which may be original issue shares or treasury shares or a combination of the two. In 2018, 3,304 shares of common stock were granted under the 2012 Incentive Plan. In 2017, 7,434 shares of common stock and 1,892 shares of restricted stock were granted under the 2012 Incentive Plan, which will vest through 2022. At December 31, 2018, there were 343,147 shares of common stock available for future awards under the 2012 Incentive Plan. The following table summarizes information about the common and restricted stock activity under the 2012 Incentive Plan: Shares Weighted- AverageGrant- Date Fair Value per Share Nonvested balance at January 1, 2016 77,528 40.57 Granted 27,077 54.44 Vested (26,294 ) 45.18 Forfeited (1,919 ) — Nonvested balance at December 31, 2016 76,392 43.91 Granted 9,326 55.58 Vested (24,839 ) 43.89 Forfeited — — Nonvested balance at December 31, 2017 60,879 45.71 Granted 3,304 59.16 Vested (24,608 ) 44.31 Forfeited — — Nonvested balance at December 31, 2018 39,575 48.93 The Company recognized compensation expense of $726,000, $884,000 and $849,000 in 2018, 2017 and 2016, respectively, related to share-based grants. The Company recognized compensation expense of $976,000, $724,000 and $334,000 in 2018 2017 and 2016, respectively, related to long-term incentive awards under the 2012 Incentive Plan. The long-term incentive award is a liability award. Non-Employee Director Restricted Stock Plan The AMERISAFE Non-Employee Director Restricted Stock Plan (the “Restricted Stock Plan”) is administered by the Compensation Committee of the Board and provides for the automatic grant of restricted stock awards to non-employee directors of the Company. Awards to non-employee directors are generally subject to terms including non-transferability, immediate vesting upon death or total disability of a director, forfeiture of unvested shares upon termination of service by a director and acceleration of vesting upon a change of control of the Company. The maximum number of shares of common stock that may be issued pursuant to restricted stock awards under the Restricted Stock Plan is 150,000 shares, subject to the authority of the Board to adjust this amount in the event of a merger, consolidation, reorganization, stock split, combination of shares, recapitalization or similar transaction affecting the common stock. At December 31, 2018, there were 57,907 shares of common stock available for future awards under the Restricted Stock Plan. Under the Restricted Stock Plan, each non-employee director is automatically granted a restricted stock award for a number of shares equal to $50,000 divided by the closing price of the Company’s common stock on the date of the annual meeting of shareholders at which the non-employee director is elected or is continuing as a member of the Board. Each restricted stock award vests on the date of the next annual meeting of shareholders following the date of grant, subject to the continued service of the non-employee director. Under the terms of the Restricted Stock Plan, the Company’s Board of Directors may increase the dollar amount of the annual award to an amount up to $75,000 without further shareholder approval. As of December 31, 2018, there were 5,761 shares of restricted stock outstanding under the Non-Employee Director Restricted Stock Plan, all of which will vest on the date of the annual meeting of shareholders in 2019. The following table summarizes information about the restricted stock activity under the Non-Employee Director Restricted Stock Plan: Shares Weighted- Average Grant- Date Fair Value per Share Nonvested balance at January 1, 2016 7,112 44.26 Granted 5,952 63.57 Vested (7,488 ) 44.54 Forfeited — — Nonvested balance at December 31, 2016 5,576 64.50 Granted 6,454 54.20 Vested (5,576 ) 64.50 Forfeited — — Nonvested balance at December 31, 2017 6,454 54.20 Granted 5,761 60.75 Vested (6,454 ) 54.20 Forfeited — — Nonvested balance at December 31, 2018 5,761 60.75 The Company recognized compensation expense of $351,000 in 2018, $355,000 in 2017 and $361,000 in 2016 related to the Non-Employee Director Restricted Stock Plan. There were no tax benefits realized for tax deductions from vesting of restricted stock in 2018 and 2017. Total tax benefits realized for tax deductions from vesting of restricted stock in 2016 was $52,000.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	13. Earnings Per Share Diluted earnings per share includes common shares assumed issued under the “treasury stock method,” which reflects the potential dilution that would occur if any outstanding options are exercised. Diluted earnings per share also includes the “if converted” method for participating securities if the result is dilutive. The calculation of basic and diluted EPS for the years ended December 31, 2018, 2017 and 2016 are presented below. For the Year Ended December 31, 2018 2017 2016 (in thousands, except earnings per share amounts) Basic EPS: Net income – basic $ 71,632 $ 46,231 $ 77,865 Basic weighted-average common shares 19,209 19,165 19,106 Basic earnings per share $ 3.73 $ 2.41 $ 4.08 Diluted EPS: Net income - diluted $ 71,632 $ 46,231 $ 77,865 Diluted weighted average common shares: Weighted average common shares 19,209 19,165 19,106 Stock options and restricted stock 84 81 98 Diluted weighted average common shares 19,293 19,246 19,204 Diluted earnings per common share $ 3.71 $ 2.40 $ 4.05 The table below sets forth the reconciliation of the weighted average shares used for the basic and diluted EPS calculation. Years Ended 2018 2017 2016 Basic weighted average common shares 19,208,978 19,165,489 19,105,806 Add: Other common shares eligible for common dividends: Weighted average restricted shares and stock options (including tax benefit component) 84,104 80,377 97,844 Diluted weighted average common shares 19,293,082 19,245,866 19,203,650

Comprehensive Income and Accumu

Comprehensive Income and Accumulated Other Comprehensive Income	12 Months Ended
	Dec. 31, 2018
Equity [Abstract]
Comprehensive Income and Accumulated Other Comprehensive Income	14. Comprehensive income includes net income plus unrealized gains/losses on our available-for-sale investment securities, net of tax. The following table illustrates the changes in the balance of each component of accumulated other comprehensive income (loss) for each period presented in the financial statements. Year Ended December 31, 2018 2017 2016 (in thousands) Beginning balance $ 3,612 $ (492 ) $ 2,587 Impact of adoption of ASU 2016-01 (615 ) — — Impact of adoption of ASU 2018-02 414 — — Adjusted beginning balance 3,411 (492 ) 2,587 Other comprehensive income (loss) before reclassification (4,551 ) 4,823 (3,231 ) Amounts reclassified from accumulated other comprehensive income (loss) 308 (719 ) 152 Net current period other comprehensive income (loss) (4,243 ) 4,104 (3,079 ) Ending balance $ (832 ) $ 3,612 $ (492 ) The sale or other-than-temporary impairment (OTTI) 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 Comprehensive Income (Loss) Year Ended December 31, Affected line item in the statement of income 2018 2017 2016 (in thousands) Unrealized gains (losses) on available-for- sale securities $ (390 ) $ 1,106 $ (234 ) Net realized losses on investments (390 ) 1,106 (234 ) Income before income taxes 82 (387 ) 82 Income tax expense $ (308 ) $ 719 $ (152 ) Net income Pre-Tax Amount Tax Expense (Benefit) Net-of-Tax Amount (in thousands) December 31, 2018 Unrealized loss on securities: Unrealized loss on available-for-sale securities $ (5,760 ) $ (1,209 ) $ (4,551 ) Reclassification adjustment for gains realized in net income 390 82 308 Net unrealized loss (5,370 ) (1,127 ) (4,243 ) Other comprehensive loss $ (5,370 ) $ (1,127 ) $ (4,243 ) December 31, 2017 Unrealized gain on securities: Unrealized gain on available-for-sale securities $ 6,960 $ 2,137 $ 4,823 Reclassification adjustment for losses realized in net income (1,106 ) (387 ) (719 ) Net unrealized gain 5,854 1,750 4,104 Other comprehensive income $ 5,854 $ 1,750 $ 4,104 December 31, 2016 Unrealized loss on securities: Unrealized loss on available-for-sale securities $ (4,908 ) $ (1,718 ) $ (3,190 ) Less amortization of differences between fair value and amortized cost for fixed maturity security transfer (63 ) (22 ) (41 ) Reclassification adjustment for gains realized in net income 234 82 152 Net unrealized loss (4,737 ) (1,658 ) (3,079 ) Other comprehensive loss $ (4,737 ) $ (1,658 ) $ (3,079 )

Employee Benefit Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2018
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plan	15. Employee Benefit Plan The Company’s 401(k) benefit plan is available to all employees. The Company matches up to 3% of employee compensation for participating employees, subject to certain limitations. Employees are fully vested in employer contributions to this plan after five years. Company contributions to this plan were $0.7 million in 2018, $0.6 million in 2017, and $0.4 million in 2016.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	16. Commitments and Contingencies The Company is a party to various legal actions arising principally from claims made under insurance policies and contracts. Those actions are considered by the Company in estimating reserves for loss and loss adjustment expenses. In the opinion of management, the ultimate disposition of these matters will not have a material adverse effect on the Company’s consolidated financial position or results of operations. The Company provides workers’ compensation insurance in several states that maintain second-injury funds. Incurred losses on qualifying claims that exceed certain amounts may be recovered from these state funds. There is no assurance that the applicable states will continue to provide funding under these programs. The Company manages risk on certain long-duration claims by settling these claims through the purchase of annuities from unaffiliated carriers. In the event these carriers are unable to meet their obligations under these contracts, the Company could be liable to the claimants. The following table summarizes (in thousands) the fair value of the annuities at December 31, 2018, that the Company has purchased to satisfy its obligations. Life Insurance Company A.M. Best Rating Statement Value of Annuities Exceeding 1% of Statutory Surplus Pacific Life and Annuity Company A+ $ 18,028 American General Life Insurance Company A 14,802 New York Life Insurance Company A++ 10,335 Travelers Life and Annuity A 12,414 Metropolitan Life Insurance Company A+ 6,799 John Hancock Life Insurance Company A+ 7,153 Athene Annuity and Life Company A 4,638 United of Omaha Life Insurance Company A+ 5,435 Other 20,470 $ 100,074 Substantially all of the annuities are issued or guaranteed by life insurance companies that have an A.M. Best Company rating of “A” (Excellent) or better. The Company leases equipment and office space under noncancelable operating leases. At December 31, 2018, future minimum lease payments are as follows (in thousands): 2019 $ 128 2020 118 2021 109 2022 110 2023 75 2024 6 $ 546 Rental expense was $0.2 million in 2018, $0.1 million in 2017 and $0.2 million in 2016, respectively.

Concentration of Operations

Concentration of Operations	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Concentration of Operations	17. Concentration of Operations The Company derives its premium revenues from its operations in the workers’ compensation insurance line of business. Net premiums earned during 2018, 2017 and 2016 for the top ten states in 2018 and all others are shown below: 2018 2017 2016 Dollars Percent Dollars Percent Dollars Percent (Dollars in thousands) Georgia $ 40,351 11.5 % $ 40,801 11.8 % $ 38,168 10.4 % Florida 39,672 11.3 % 34,615 10.0 % 29,051 7.9 % Pennsylvania 31,708 9.1 % 32,931 9.5 % 39,460 10.7 % Louisiana 25,810 7.4 % 25,422 7.3 % 30,426 8.3 % Illinois 19,710 5.6 % 22,169 6.4 % 25,796 7.0 % North Carolina 19,537 5.6 % 18,388 5.3 % 20,784 5.6 % Virginia 15,228 4.3 % 16,298 4.7 % 16,599 4.5 % Wisconsin 14,101 4.0 % 13,790 4.0 % 13,544 3.7 % South Carolina 13,924 4.0 % 13,327 3.9 % 13,897 3.8 % Minnesota 12,900 3.7 % 13,968 4.0 % 15,130 4.1 % All others 117,385 33.5 % 114,447 33.1 % 125,849 34.0 % Total net premiums earned $ 350,326 100.0 % $ 346,156 100.0 % $ 368,704 100.0 %

Fair Values of Financial Instru

Fair Values of Financial Instruments	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Values of Financial Instruments	18. Fair Values of Financial Instruments 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. Cash and Cash Equivalents —The carrying amounts reported in the accompanying consolidated balance sheets for these financial instruments approximate their fair values. Investments —The Company’s fixed maturity securities are priced by an independent pricing service. The prices provided by the independent pricing service are estimated based on observable market data in active markets utilizing pricing models and processes, which may include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, benchmark securities, bids, offers, sector groupings, matrix pricing and reference data. The Company reviews the prices provided by pricing services for reasonableness and compares them to prices provided by the Company’s custodian which uses different pricing services. Short Term Investments —The carrying amounts reported in the accompanying consolidated balance sheets for these financial instruments approximate their fair value. Other Investments — Other investments consisted of a limited partnership interest that was accounted for under the equity method valued using the net asset value provided by the general partner of the limited partnership, which approximates the fair value of the interest. The limited partnership’s objective was to generate absolute returns by investing long and short in publicly-traded global securities. The investment in the limited partnership was fully redeemed during 2017. The Company has no unfunded commitments to the limited partnership. The following table summarizes the carrying or reported values and corresponding fair values for financial instruments: December 31, 2018 2017 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Assets: Fixed maturity securities—held to maturity $ 613,878 $ 616,772 $ 629,668 $ 639,309 Fixed maturity securities—available-for-sale 478,730 478,730 465,594 465,594 Equity securities 18,651 18,651 9,282 9,282 Short-term investments 14,231 14,231 25,770 25,770 Cash and cash equivalents 40,344 40,344 55,559 55,559 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 year ended December 31, 2018. Assets and liabilities measured at fair value on a recurring basis as of December 31, 2018 and 2017 are as follows: 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 December 31, 2017 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 $ — $ 251,140 $ — $ 251,140 Corporate bonds — 130,222 — 130,222 U.S. agency-based mortgage-backed securities — 18,014 — 18,014 U.S. Treasury securities and obligations of U.S. government agencies 66,218 — — 66,218 Total available-for-sale—fixed maturity 66,218 399,376 — 465,594 Securities available-for-sale—equity: Domestic common stock 9,248 — 34 9,282 Total available-for-sale $ 75,466 $ 399,376 $ 34 $ 474,876 Assets and liabilities measured at amortized cost as of December 31, 2018 and 2017 are as follows: 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 December 31, 2017 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Securities held-to-maturity—fixed maturity: States and political subdivisions $ — $ 469,101 $ — $ 469,101 Corporate bonds — 100,047 — 100,047 U.S. agency-based mortgage-backed securities — 10,845 — 10,845 U.S. Treasury securities 6,750 — — 6,750 Obligations of U.S. government agencies — 51,257 — 51,257 Asset-backed securities — 1,309 — 1,309 Total held-to-maturity $ 6,750 $ 632,559 $ — $ 639,309 The following table presents summary information regarding changes in the fair value of assets measured at fair value using Level 3 input. Year Ended Twelve Months Ended December 31, 2018 December 31, 2017 (in thousands) Balance, beginning of period $ 34 $ — Transfer into Level 3 — 34 Unrealized loss on equity security (32 ) — Sale of equity security (2 ) Balance, end of period $ — $ 34 There was an immaterial transfer between Level 1 and Level 3 in 2017 due to the reclassification of a common stock security with unobservable fair value inputs. At December 31, 2018, the Company held one security measured at fair value on a nonrecurring basis due to a recognized impairment of $100,000. The security is valued using Level 2 inputs and had a value of $11,000 at December 31, 2018. The security was valued at fair value at the time of impairment and is currently being carried at the adjusted amortized cost. The fair value of the security is $31,000 at December 31, 2018.

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (Unaudited)	19. Quarterly Financial Data (Unaudited) The following table represents unaudited quarterly financial data for the years ended December 31, 2018 and 2017. Three Months Ended March 31 June 30 September 30 December 31 (in thousands, except per share amounts) 2018 Net premiums earned $ 87,310 $ 88,995 $ 85,184 $ 88,837 Net investment income 7,209 7,303 7,884 8,056 Net realized losses on investments (31 ) (1,111 ) (329 ) (65 ) Total revenues 94,175 95,380 93,529 94,669 Income before income taxes 19,414 20,930 24,460 22,777 Net income 16,169 16,956 19,701 18,806 Earnings per share: Basic $ 0.84 $ 0.88 $ 1.03 $ 0.98 Diluted $ 0.84 $ 0.88 $ 1.02 $ 0.98 Comprehensive income 10,321 17,109 17,582 22,176 Extraordinary cash dividends declared per common share $ — $ — $ — $ 3.50 Cash dividends declared per common share $ 0.22 $ 0.22 $ 0.22 $ 0.22 2017 Net premiums earned $ 90,912 $ 82,749 $ 85,118 $ 87,377 Net investment income 6,710 7,471 7,788 7,312 Net realized gains (losses) on investments (181 ) (388 ) (192 ) 114 Total revenues 97,542 89,925 92,804 94,937 Income before income taxes 18,733 22,151 23,556 17,800 Net income 13,524 15,481 16,577 649 Earnings per share: Basic $ 0.71 $ 0.81 $ 0.86 $ 0.03 Diluted $ 0.70 $ 0.81 $ 0.86 $ 0.03 Comprehensive income 14,476 17,437 17,194 1,228 Extraordinary cash dividends declared per common share $ — $ — $ — $ 3.50 Cash dividends declared per common share $ 0.20 $ 0.20 $ 0.20 $ 0.20

Capital Management

Capital Management	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Capital Management	20. Capital Management 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 2018. Since the beginning of this plan, the Company has repurchased a total of 1,258,250 shares for $22.4 million, or an average price of $17.78, including commissions. In 2013, the Company’s Board of Directors initiated a regular quarterly dividend. During 2018, the Company’s Board of Directors declared a quarterly dividend of $0.22 per share compared to $0.20 per share in 2017, $0.18 per share in 2016, $0.15 per share in 2015, $0.12 per share in 2014 and $0.08 per share in 2013. The Company declared extraordinary dividends totaling $3.50 per share in 2018 and 2017, $3.25 per share in 2016, $3.00 per share in 2015 and $1.50 per share in 2014. The Company did not pay any extraordinary cash dividends in 2013.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	21. Subsequent Events On February 26, 2019 the Company declared a regular quarterly cash dividend of $0.25 per share payable on March 22, 2019 to shareholders of record as of March 8, 2019. The Board intends to continue to consider the payment of a regular cash dividend each calendar quarter. On an annualized basis, the cash dividend is expected to be $1.00 per share.

Schedule II. Condensed Financia

Schedule II. Condensed Financial Information of Registrant	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Of Parent Company Only Disclosure [Abstract]
Schedule II. Condensed Financial Information of Registrant	AMERISAFE, INC. CONDENSED BALANCE SHEETS December 31, 2018 2017 (in thousands) Assets Investments: Equity securities, at fair value (cost $10,007 and $8,503 in 2018 and 2017, respectively) $ 9,803 $ 9,248 Short-term investments — 7,962 Investment in subsidiaries 388,797 386,844 Total investments 398,600 404,054 Cash and cash equivalents 5,509 16,351 Deferred income taxes 509 302 Notes receivable from subsidiaries 3,270 1,711 Property and equipment, net 1,536 1,359 Federal income tax recoverable 2,995 — Other assets 800 4,412 $ 413,219 $ 428,189 Liabilities, redeemable preferred stock and shareholders’ equity Total liabilities 3,457 2,766 Shareholders' equity (net of Treasury stock of $22,370 at December 31, 2018 and 2017) 409,762 425,423 $ 413,219 $ 428,189 Schedule II. Condensed Financial Information of Registrant – (Continued) AMERISAFE, INC. CONDENSED STATEMENTS OF INCOME Year Ended December 31, 2018 2017 2016 (in thousands) Revenues Net investment income $ 1,089 $ 679 $ 1,509 Net unrealized losses on equity securities (948 ) — — Fee and other income 7,389 6,890 5,843 Total revenues 7,530 7,569 7,352 Expenses Other operating costs 7,530 7,569 7,352 Total expenses 7,530 7,569 7,352 Income (loss) before income taxes and equity in earnings of subsidiaries — — — Income tax expense (benefit) (36 ) 125 (156 ) Gain (loss) before equity in earnings of subsidiaries 36 (125 ) 156 Equity in net income of subsidiaries 71,596 46,356 77,709 Net income $ 71,632 $ 46,231 $ 77,865 Schedule II. Condensed Financial Information of Registrant – (Continued) AMERISAFE, INC. CONDENSED STATEMENTS OF CASH FLOWS Year Ended December 31, 2018 2017 2016 (in thousands) Operating activities Net cash provided by operating activities $ 2,448 $ 15,138 $ 2,771 Investing activities Purchases of investments (47,825 ) (37,361 ) (11,940 ) Proceeds from sales of investments 54,600 33,000 — Purchases of property and equipment (1,041 ) (277 ) (924 ) Dividends from subsidiary 65,400 78,900 67,000 Net cash provided by investing activities 71,134 74,262 54,136 Financing activities Proceeds from stock option exercises 67 — 837 Tax benefit from share-based payments — — 995 Dividends to shareholders (84,491 ) (82,645 ) (76,111 ) Net cash used in financing activities (84,424 ) (82,645 ) (74,279 ) Change in cash and cash equivalents (10,842 ) 6,755 (17,372 ) Cash and cash equivalents at beginning of year 16,351 9,596 26,968 Cash and cash equivalents at end of year $ 5,509 $ 16,351 $ 9,596

Schedule VI. Supplemental Infor

Schedule VI. Supplemental Information Concerning Property-Casualty Insurance Operations	12 Months Ended
	Dec. 31, 2018
Supplemental Information For Property Casualty Insurance Underwriters [Abstract]
Schedule VI. Supplemental Information Concerning Property-Casualty Insurance Operations	AMERISAFE, INC. AND SUBSIDIARIES Deferred Policy Acquisition Costs Reserves for Unpaid Loss and Loss Adjustment Expense Unearned Premium Net Premiums Earned Net Investment Income Loss and LAE Related to Current Period Loss and LAE Related to Prior Periods Amortization of Deferred Policy Acquisition Costs Paid Claims and Claim Adjustment Expenses Net Premiums Written (in thousands) 2018 $ 19,734 $ 798,409 $ 149,296 $ 350,326 $ 30,452 $ 250,487 $ (45,596 ) $ (45,769 ) $ 200,654 $ 342,352 2017 20,251 771,845 157,270 346,156 29,281 244,094 (34,770 ) (43,009 ) 186,888 341,398 2016 19,300 742,776 162,028 368,704 28,106 250,337 (51,306 ) (44,321 ) 187,686 362,748

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Organization	Organization AMERISAFE, Inc. is an insurance holding company incorporated in the state of Texas. The accompanying 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, agriculture, maritime, and oil and gas. Assets and revenues of AIIC and its subsidiaries represent at least 95% of comparable consolidated amounts of the Company for each of 2018, 2017 and 2016.
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Adopted Accounting Guidance	Adopted Accounting Guidance In January 2016, the Financial Accounting Standards Board (“FASB”) issued ASU 2016-01, Financial Instruments – Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. This guidance requires fair value measurement for equity investments (not including those that result in consolidation of the investee or use the equity method of accounting) and the recognition of changes in fair value to be presented as a component of net income. The guidance also revises the disclosure requirements related to fair value changes of liabilities presented in comprehensive income, eliminates disclosure related to the methods and assumptions underlying fair value for financial instruments measured at amortized cost, and simplifies impairment assessments for equity investments without readily determinable fair values. The adoption of this new guidance in the first quarter of 2018 resulted in an immaterial decrease in net income of $390 thousand or a $0.02 decrease to our diluted earnings per common share. At December 31, 2017, equity investments were classified as available-for-sale on the Company’s balance sheet. However, upon adoption, the updated guidance eliminated the available-for-sale balance sheet classification for equity investments. In May 2014, the FASB issued ASU 2014-09 (Topic 606): Revenue from Contract s In February 2018, the FASB issued ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220). This ASU provided new guidance on reclassification from Other Comprehensive Income (“OCI”) of tax effects related to the recently passed tax reform legislation (the “Tax Act”). The guidance gives entities the option to reclassify to retained earnings tax effects related to items in accumulated OCI deemed to be stranded as a result of tax reform. The guidance was effective for us in the first quarter of 2018 and was applied retrospectively. The Company’s policy for releasing income tax effects from accumulated OCI was the individual securities approach for available-for-sale securities. The adoption of this guidance did not have a material impact on our financial condition and results of operations. In December 2017, the SEC issued Staff Accounting Bulletin (SAB) 118 which provided guidance on accounting for tax effects of the Tax Act. Among many changes of the Tax Act which affected Property and Casualty Insurers, the Tax Act required property and casualty taxpayers to discount loss reserves based solely on IRS factors and no longer by reference to historical payment patterns. In December 2018, the IRS released its guidance for determining the Tax Act transition adjustment along with its 2018 loss reserves discounting factors. The Company has completed its analysis for the tax effects relating to the Tax Act. During the period ended December 31, 2018, the Company recognized an increase in the deferred tax balance of $1.5 million to the provisional amounts recorded at December 31, 2017.
Prospective Accounting Guidance	Prospective Accounting Guidance In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). Under current guidance for lessees, leases are only included on the balance sheet if certain criteria, classifying the contract as a capital lease, are met. The new guidance requires a lessee to recognize a lease liability and a right of use asset for all leases extending beyond twelve months. The new guidance is effective for us in the first quarter of 2019. We will elect the new transition method under the transition guidance within the new standard which means prior comparative periods will not be adjusted. We will also elect the package of practical expedients, which among other things, allows us to carryforward the historical lease classification. We will make an accounting policy election not to recognize lease assets and lease liabilities for short-term operating leases. Adoption of the guidance is not expected to have a material effect on the Company’s consolidated financial statements as the Company does not have any significant leases. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses. The new guidance replaces the methodology of credit loss impairment, which currently, delays the recognition of credit losses until a probable loss has been incurred. 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 allowance account that will run through the income statement. The same method will be used for available-for-sale securities, but the valuation allowance 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. The Company will continue to monitor and evaluate the impact as the implementation date approaches. All other issued but not yet effective accounting and reporting standards as of December 31, 2018 are either not applicable to the Company or are not expected to have a material impact on the Company.
Investments	Investments The Company has the ability and positive intent to hold certain investments until maturity. Therefore, fixed maturity securities classified as held-to-maturity are recorded at amortized cost. Fixed maturity securities classified as available-for-sale are recorded at fair value. Temporary changes in the fair value of these securities are reported in shareholders’ equity as a component of other comprehensive income, net of deferred income taxes. Changes in the fair value of equity securities are recorded in net income. 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. The Company regularly reviews the fair value of its investments. Impairment of an investment security results in a reduction of the carrying value of the security and the realization of a loss when the fair value of the security declines below the cost or amortized cost, as applicable, for the security and the impairment is deemed to be other-than-temporary. The Company regularly reviews its investment portfolio to evaluate the existence of other-than-temporary declines in the fair value of investments. The Company considers various factors in determining if a decline in the fair value of an individual security is other-than-temporary, including but not limited to a reduction or interruption in scheduled cash flows, the financial condition of the issuer, how long and by how much the fair value has been below amortized cost, losses due to credit concerns, downgrades and the Company’s intent to sell or ability to hold the security. Impairment losses on fixed maturities are recognized in the financial statements depending on the facts and circumstances related to the specific security. If we intend to sell a security or it is more likely than not that we would be required to sell a security before the recovery of its amortized cost, less any current period credit loss, an other-than-temporary impairment would be recognized in net income for the difference between amortized cost and fair value. If we do not expect to recover the amortized cost basis, we do not plan to sell the security and if it is not more likely than not that we would be required to sell a security before the recovery of its amortized cost, less any current period credit loss, the recognition of the other-than-temporary impairment is bifurcated. The credit loss portion would be recognized in net income and the noncredit loss portion in other comprehensive income.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents include short-term money market funds with an original maturity of 90 days or less.
Short-Term Investments	Short-Term Investments Short-term investments include municipal securities and corporate bonds with an original maturity greater than 90 days but less than one year.
Other Investments	Other Investments Other investments consisted of a limited partnership interest that was accounted for under the equity method, valued using the net asset value provided by the general partner of the limited partnership, which approximates the fair value of the interest. The limited partnership’s objective was to generate absolute returns by investing long and short in publicly-traded global securities. The investment in the limited partnership was fully redeemed during 2017. The Company has no unfunded commitments to the limited partnership.
Premiums Receivable	Premiums Receivable Premiums receivable consist primarily of premium-related balances due from policyholders. The Company considers premiums receivable as past due based on the payment terms of the underlying policy. The balance is shown net of the allowance for doubtful accounts. Receivables due from insureds are charged off when a determination has been made by management that a specific balance will not be collected. An estimate of amounts that are likely to be charged off is established as an allowance for doubtful accounts as of the balance sheet date. The estimate is primarily comprised of specific balances that are considered probable to be charged off after all collection efforts have ceased, as well as historical trends and an analysis of the aging of the receivables.
Property and Equipment	Property and Equipment The Company’s property and equipment, including certain costs incurred to develop or obtain software for internal use, are stated at cost less accumulated depreciation. Depreciation is calculated primarily by the straight-line method over the estimated useful lives of the respective assets, generally 39 years for buildings and three to seven years for all other fixed assets.
Deferred Policy Acquisition Costs	Deferred Policy Acquisition Costs The direct costs of successfully acquiring and renewing business are capitalized to the extent recoverable and are amortized over the effective period of the related insurance policies in proportion to premium revenue earned. These capitalized costs consist mainly of sales commissions, premium taxes and other underwriting costs. The Company evaluates deferred policy acquisition costs for recoverability by comparing the unearned premiums to the estimated total expected claim costs and related expenses, offset by anticipated investment income. The Company would reduce the deferred costs if the unearned premiums were less than expected claims and expenses after considering investment income, and report any adjustments in amortization of deferred policy acquisition costs. There were no adjustments necessary in 2018, 2017 or 2016.
Reserves for Loss and Loss Adjustment Expenses	Reserves for Loss and Loss Adjustment Expenses Reserves for loss and loss adjustment expenses represent the estimated ultimate cost of all reported and unreported losses incurred through December 31. The Company does not discount loss and loss adjustment expense reserves. 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 and adjusted as necessary as experience develops or new information becomes known. Any such adjustments are included in income from current operations. Subrogation recoverables, as well as deductible recoverables from policyholders, are estimated using individual case-basis valuations and aggregate estimates. Deductibles that are recoverable from policyholders and other recoverables from state funds decrease the liability for loss and loss adjustment expenses. The Company funds its obligations under certain settled claims where the payment pattern and ultimate cost are fixed and determinable on an individual claim basis through the purchase of annuities. These annuities are purchased from unaffiliated carriers and name the claimant as payee. The cost of purchasing the annuity is recorded as paid loss and loss adjustment expenses. To the extent the annuity funds estimated future claims, reserves for loss and loss adjustment expense are reduced.
Premium Revenue	Premium Revenue Premiums on workers’ compensation insurance are based on actual payroll costs or production during the policy term and are normally billed monthly in arrears or annually. However, the Company generally requires a deposit at the inception of a policy. Premium revenue is earned on a pro rata basis over periods covered by the policies. The reserve for unearned premiums on these policies is computed on a daily pro rata basis. The Company estimates the annual premiums to be paid by its policyholders when the Company issues the policies and records those amounts on the balance sheet as premiums receivable. The Company conducts premium audits on all of its voluntary business policyholders annually, upon the expiration of each policy, including when the policy is renewed. The purpose of these audits is to verify that policyholders have accurately reported their payroll expenses and employee job classifications, and therefore have paid the Company the premium required under the terms of the policies. The difference between the estimated premium and the ultimate premium is referred to as “earned but unbilled” premium, or EBUB premium. EBUB premium can be higher or lower than the estimated premium. EBUB premium is subject to significant variability and can either increase or decrease earned premium based upon several factors, including changes in premium growth, industry mix and economic conditions. Due to the timing of audits and other adjustments, ultimate premium earned is generally not determined for several months after the expiration of the policy. The Company estimates EBUB premiums on a quarterly basis using historical data and applying various assumptions based on the current market and economic conditions, and records an adjustment to premium, related losses, and expenses as warranted.
Reinsurance	Reinsurance Reinsurance premiums, losses and allocated loss adjustment expenses are accounted for on a basis consistent with those used in accounting for the original policies issued and the terms of the reinsurance contracts. Amounts recoverable from reinsurers include balances currently owed to the Company for losses and allocated loss adjustment expenses that have been paid to policyholders, amounts that are currently reserved for and will be recoverable once the related expense has been paid and experience-rated commissions recoverable upon commutation. Upon management’s determination that an amount due from a reinsurer is uncollectible due to the reinsurer’s insolvency or other matters, the amount is written off. Ceding commissions are earned from certain reinsurance companies and are intended to reimburse the Company for policy acquisition costs related to those premiums ceded to the reinsurers. Ceding commission income is recognized over the effective period of the related insurance policies in proportion to premium revenue earned and is reflected as a reduction in underwriting and certain other operating costs. Experience-rated commissions are earned from certain reinsurance companies based on the financial results of the applicable risks ceded to the reinsurers. These commission revenues on reinsurance contracts are recognized during the related reinsurance treaty period and are based on the same assumptions used for recording loss and allocated loss adjustment expenses. These commissions are reflected as a reduction in underwriting and certain other operating costs and are adjusted as necessary as experience develops or new information becomes known. Any such adjustments are included in income from current operations. Experience-rated commissions increased underwriting and certain other operating costs by $0.2 million in 2018 and 2017 and had minimal impact in 2016. In December 2016, the Company commuted reinsurance agreements with Hannover Reinsurance Limited (Ireland) (“Hannover”) and Tokio Millennium Re Limited (“Tokio”) covering portions of accident years 2011 through 2013. The Company received cash of $0.2 million and an additional $25.4 million payment effectuated solely through offset against the balance of the funds withheld account under the reinsurance agreements in exchange for releasing Hannover and Tokio from their reinsurance obligations under the commuted agreements. Both Hannover and Tokio remain obligated to the subsidiaries of the Company under other reinsurance agreements. As a result of the commutation, the effect on the Company’s net income in the year ended December 31, 2016 was immaterial.
Fee and Other Income	Fee and Other Income The Company recognizes income related to commissions earned by AGAI as the related services are performed.
Advertising	Advertising All advertising expenditures incurred by the Company are charged to expense in the period to which they relate and are included in underwriting and certain other operating costs in the consolidated statements of income. Total advertising expenses incurred were $0.5 million in 2018 and 2017, and $0.7 million in 2016.
Income Taxes	Income Taxes The Company accounts for income taxes using the liability method. The provision for income taxes has two components, amounts currently payable or receivable and deferred amounts. Deferred income tax assets and liabilities are recognized for the differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred income tax assets and liabilities are measured using tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred income tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company considers deferred tax assets to be recoverable if it is probable that the related tax losses can be offset by future taxable income. The Company includes reversal of existing temporary differences, tax planning strategies available and future operating income in this assessment. To the extent the deferred tax assets exceed the amount expected to be recovered in future years, the Company records a valuation allowance for the amount determined unrecoverable.
Insurance-Related Assessments	Insurance-Related Assessments Insurance-related assessments are accrued in the period in which they have been incurred. The Company is subject to a variety of assessments related to insurance commerce, including those by state guaranty funds and workers’ compensation second-injury funds. State guaranty fund assessments are used by state insurance oversight agencies to cover losses of policyholders of insolvent or rehabilitated insurance companies and for the operating expenses of such agencies. Assessments based on premiums are generally paid one year after the calendar year in which the premium is written, while assessments based on losses are generally paid within one year of the calendar year in which the loss is paid.
Policyholder Dividends	Policyholder Dividends The Company writes certain policies for which the policyholder may participate in favorable claims experience through a dividend. An estimated provision for workers’ compensation policyholders’ dividends is accrued as the related premiums are earned. Dividends do not become a fixed liability unless and until declared by the respective Boards of Directors of AMERISAFE’s insurance subsidiaries. The dividend to which a policyholder may be entitled is set forth in the policy and is related to the amount of losses sustained under the policy. Dividends are calculated after the policy expiration. The Company is able to estimate the policyholder dividend liability because the Company has information regarding the underlying loss experience of the policies written with dividend provisions and can estimate future dividend payments from the policy terms.
Earnings Per Share	Earnings Per Share The Company computes earnings per share (EPS) in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) Topic 260, Earnings Per Share. Basic EPS is calculated by dividing income available to common shareholders 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 or warrants were exercised or restricted stock becomes vested.
Share-Based Compensation	Share-Based Compensation The Company recognizes the impact of its share-based compensation in accordance with FASB ASC Topic 718, Compensation-Stock Compensation.
Fair Values of Financial Instruments	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.

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2018
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 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 held-to-maturity at December 31, 2017 are summarized as follows: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) States and political subdivisions $ 460,428 $ 9,628 $ (955 ) $ 469,101 Corporate bonds 100,024 190 (167 ) 100,047 U.S. agency-based mortgage-backed securities 10,260 625 (40 ) 10,845 U.S. Treasury securities and obligations of U.S. government agencies 57,657 548 (198 ) 58,007 Asset-backed securities 1,299 25 (15 ) 1,309 Totals $ 629,668 $ 11,016 $ (1,375 ) $ 639,309
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 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 or amortized cost and fair value of, those investments classified as available-for-sale at December 31, 2017 are summarized as follows: Cost or Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value (in thousands) Fixed maturity: States and political subdivisions $ 244,898 $ 6,819 $ (577 ) $ 251,140 Corporate bonds 130,210 224 (212 ) 130,222 U.S. agency-based mortgage-backed securities 18,813 — (799 ) 18,014 U.S. Treasury securities and obligations of U.S. government agencies 67,315 29 (1,126 ) 66,218 Total fixed maturity 461,236 7,072 (2,714 ) 465,594 Equity securities 8,503 779 — 9,282 Totals $ 469,739 $ 7,851 $ (2,714 ) $ 474,876
Gross Unrealized Gains and Losses and Cost of Equity	The gross unrealized gains and losses on, and the cost of equity securities at December 31, 2018 are summarized as follows: Cost Gross Unrealized Gains Gross Unrealized 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 Company's Realized Gains and Losses on Sales, Calls or Redemptions of Investments	A summary of the Company’s realized gains and losses on sales, calls or redemptions of investments for 2018, 2017 and 2016 is as follows: Fixed Maturity Securities Available for Sale Equity Securities Other Total (in thousands) Year ended December 31, 2018 Proceeds from sales $ 15,025 $ 3 $ — $ 15,028 Gross realized investment gains $ 238 $ 1 $ — $ 239 Gross realized investment losses (1,354 ) — — (1,354 ) Net realized investment gains (losses) (1,116 ) 1 — (1,115 ) Other, including losses on calls and redemptions (144 ) — (277 ) (421 ) Net realized gains (losses) on investments $ (1,260 ) $ 1 $ (277 ) $ (1,536 ) Year ended December 31, 2017 Proceeds from sales $ 14,591 $ 1 $ 13,172 $ 27,764 Gross realized investment gains $ 485 $ 1 $ — $ 486 Gross realized investment losses (5 ) — — (5 ) Net realized investment gains 480 1 — 481 Other, including losses on calls and redemptions (520 ) — (608 ) (1,128 ) Net realized gains (losses) on investments $ (40 ) $ 1 $ (608 ) $ (647 ) Year ended December 31, 2016 Proceeds from sales $ 54,730 $ — $ 4,609 $ 59,339 Gross realized investment gains $ 823 $ — $ 68 $ 891 Gross realized investment losses (1,728 ) — — (1,728 ) Net realized investment gains (losses) (905 ) — 68 (837 ) Other, including gains on calls and redemptions 274 — 69 343 Net realized gains (losses) on investments $ (631 ) $ — $ 137 $ (494 )
Major Categories of the Company's Net Investment Income	Major categories of the Company’s net investment income are summarized as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Gross investment income: Fixed maturity securities $ 28,762 $ 28,961 $ 27,837 Equity securities 448 201 — Short-term investments and cash and cash equivalents 2,208 1,117 348 Other investments — 104 1,568 Total gross investment income 31,418 30,383 29,753 Investment expenses (966 ) (1,102 ) (1,647 ) Net investment income $ 30,452 $ 29,281 $ 28,106
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) 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 December 31, 2017 Held-to-Maturity Fixed maturity securities: States and political subdivisions $ 110,698 $ 654 $ 19,895 $ 301 $ 130,593 $ 955 Corporate bonds 56,425 156 4,121 11 60,546 167 U.S. agency-based mortgage-backed securities 2,798 40 — — 2,798 40 U.S. Treasury securities and obligations of U.S. government agencies 48,153 122 3,948 76 52,101 198 Asset-backed securities — — 967 15 967 15 Total held-to-maturity securities 218,074 972 28,931 403 247,005 1,375 Available-for-Sale Fixed maturity securities: States and political subdivisions $ 23,365 $ 86 $ 19,153 $ 491 $ 42,518 $ 577 Corporate bonds 82,795 171 5,888 41 88,683 212 U.S. agency-based mortgage-backed securities 14,686 59 3,328 740 18,014 799 U.S. Treasury securities and obligations of U.S. government agencies 14,730 204 47,716 922 62,446 1,126 Total available-for-sale securities 135,576 520 76,085 2,194 211,661 2,714 Total $ 353,650 $ 1,492 $ 105,016 $ 2,597 $ 458,666 $ 4,089
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 December 31, 2018, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 76,875 $ 76,861 After one year through five years 256,614 257,530 After five years through ten years 81,311 81,755 After ten years 189,926 191,213 U.S. agency-based mortgage-backed securities 8,102 8,349 Asset-backed securities 1,050 1,064 Totals $ 613,878 $ 616,772
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 December 31, 2018, by contractual maturity, is as follows: Amortized Cost Fair Value (in thousands) Maturity: Within one year $ 61,650 $ 61,435 After one year through five years 175,743 174,213 After five years through ten years 47,058 46,725 After ten years 182,486 183,842 U.S. agency-based mortgage-backed securities 12,835 12,515 Totals $ 479,772 $ 478,730

Premiums Receivable (Tables)

Premiums Receivable (Tables)	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Components of Premiums Receivable	The components of premiums receivable are shown below: December 31, 2018 2017 (in thousands) Premiums receivable $ 167,868 $ 179,460 Allowance for doubtful accounts (5,390 ) (5,226 ) Premiums receivable, net $ 162,478 $ 174,234
Summary of Activity in Allowance for Doubtful Accounts	The following summarizes the activity in the allowance for doubtful accounts: December 31, 2018 2017 2016 (in thousands) Balance, beginning of year $ 5,226 $ 5,212 $ 4,852 Provision for bad debts 883 1,394 1,646 Write-offs (719 ) (1,380 ) (1,286 ) Balance, end of year $ 5,390 $ 5,226 $ 5,212

Deferred Policy Acquisition C_2

Deferred Policy Acquisition Costs (Tables)	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Schedule of Major Categories of the Deferred Policy Acquisition Costs	Major categories of the Company’s deferred policy acquisition costs are summarized as follows: December 31, 2018 2017 (in thousands) Agents’ commissions $ 14,953 $ 15,238 Premium taxes 3,161 3,395 Deferred underwriting expenses 1,620 1,618 Total deferred policy acquisition costs $ 19,734 $ 20,251
Schedule of the Activity in the Deferred Policy Acquisition Costs	The following summarizes the activity in the deferred policy acquisition costs: Year Ended December 31, 2018 2017 2016 (in thousands) Balance, beginning of year $ 20,251 $ 19,300 $ 20,412 Policy acquisition costs deferred 45,252 43,960 43,209 Amortization expense during the year (45,769 ) (43,009 ) (44,321 ) Balance, end of year $ 19,734 $ 20,251 $ 19,300

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2018
Property Plant And Equipment [Abstract]
Schedule of Property and Equipment	Property and equipment consist of the following: December 31, 2018 2017 (in thousands) Land and office building $ 7,798 $ 7,713 Furniture and equipment 6,150 6,578 Software 7,339 6,856 Automobiles 74 74 21,361 21,221 Accumulated depreciation (15,103 ) (15,093 ) Property and equipment, net $ 6,258 $ 6,128
Schedule of Future Minimum Lease Payments for Capital Lease Obligations	Future minimum lease payments related to the capital lease obligations are detailed below (in thousands): 2019 $ 47 2020 48 2021 4 Present value of net minimum lease payments $ 99

Reinsurance (Tables)

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Schedule of the Effect of Reinsurance on Premiums Written and Earned	The effect of reinsurance on premiums written and earned in 2018, 2017 and 2016 was as follows: 2018 Premiums 2017 Premiums 2016 Premiums Written Earned Written Earned Written Earned (in thousands) Gross $ 351,696 $ 359,670 $ 350,267 $ 355,025 $ 373,055 $ 379,011 Ceded (9,344 ) (9,344 ) (8,869 ) (8,869 ) (10,307 ) (10,307 ) Net premiums $ 342,352 $ 350,326 $ 341,398 $ 346,156 $ 362,748 $ 368,704
Schedule of the Amounts Recoverable from Reinsurers	The amounts recoverable from reinsurers consist of the following: December 31, 2018 2017 (in thousands) Unpaid losses recoverable: Case basis $ 76,525 $ 66,061 Incurred but not reported 30,691 18,828 Paid losses recoverable 325 554 Experience-rated commissions recoverable 4,465 4,690 Total $ 112,006 $ 90,133
Schedule of Unsecured Reinsurance Recoverables from Reinsurers	Reinsurer A.M. Best Rating Amounts Recoverable as of December 31, 2018 (in thousands) Hannover Reinsurance (Ireland) Limited (1) A+ $ 53,609 Allianz Risk Transfer AG (Bermuda) (1) A+ 13,084 Odyssey America Reinsurance Corporation A 11,754 Minnesota Workers’ Compensation Reinsurance Association (1) NR 8,823 Other reinsurers 24,736 Total amounts recoverable from reinsurers 112,006 Funds withheld and letters of credit related to the above recoverables (69,932 ) Total unsecured amounts recoverable from reinsurers $ 42,074 (1) Current participant in our 2019 reinsurance program.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Company's Deferred Income Tax Assets and Liabilities	The Company’s deferred income tax assets and liabilities are as follows: December 31, 2018 2017 (in thousands) Deferred income tax assets: Discounting of net unpaid loss and loss adjustment expenses $ 21,377 $ 8,830 Unearned premiums 8,069 8,466 Accrued expenses and other 2,636 2,359 State income tax 855 782 Accrued policyholder dividends 2,188 1,918 Impaired securities 21 42 Capital loss carryforward — 190 Accrued insurance-related assessments 3,139 3,256 Net unrealized loss on securities 496 — Total deferred tax assets 38,781 25,843 Deferred income tax liabilities: Deferred policy acquisition costs (5,207 ) (5,317 ) Callable bond amortization (5 ) (8 ) Unrealized gain on securities available-for-sale — (1,070 ) Property and equipment and other (178 ) (3 ) Salvage and subrogation (719 ) (183 ) Loss reserves adjustment due to the Tax Act (10,820 ) — Total deferred income tax liabilities (16,929 ) (6,581 ) Net deferred income taxes $ 21,852 $ 19,262
Components of Consolidated Income Tax Expense (Benefit)	The components of consolidated income tax expense (benefit) are as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Current: Federal $ 16,407 $ 22,477 $ 35,602 State 1,004 732 1,603 17,411 23,209 37,205 Deferred: Federal (1,389 ) 12,965 (2,120 ) State (73 ) (165 ) (129 ) (1,462 ) 12,800 (2,249 ) Total $ 15,949 $ 36,009 $ 34,956
Income Tax Expense from Operations from the Amount Computed by Applying the U.S. Federal Income Tax Statutory Rate of 35% to Income Before Income Taxes	Income tax expense from operations is different from the amount computed by applying the U.S. federal income tax statutory rate of 21% in 2018 and 35% in 2017 and 2016 to income before income taxes as follows: Year Ended December 31, 2018 2017 2016 (in thousands) Income tax computed at federal statutory tax rate $ 18,392 $ 28,784 $ 39,487 Tax-exempt interest, net (2,965 ) (5,707 ) (5,370 ) State income tax 720 311 913 Dividends received deduction (44 ) (48 ) (125 ) Revaluation of net deferred income tax assets — 12,620 — Other (154 ) 49 51 $ 15,949 $ 36,009 $ 34,956

Loss and Loss Adjustment Expe_2

Loss and Loss Adjustment Expenses (Tables)	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Summary of Development Tables of Incurred and Paid Claims and Allocated Claim Adjustment Expenses Net of Reinsurance	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance As of For the Years Ended December 31, December 31, 2018 (Dollars in thousands) Total IBNR Plus Expected Cumulative Development Number of Accident Unaudited (1) on Reported Claims Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Claims Reported 2009 $ 185,359 $ 188,746 $ 188,462 $ 187,943 $ 184,006 $ 182,274 $ 177,795 $ 176,586 $ 177,015 $ 174,731 $ 3,407 5,372 2010 — 179,156 202,479 208,035 205,769 198,861 193,029 191,000 189,403 189,040 5,612 5,970 2011 — — 196,384 199,522 199,163 198,213 195,262 192,988 191,126 189,327 7,045 6,043 2012 — — — 222,549 222,075 212,738 193,515 184,460 182,859 180,387 7,454 5,749 2013 — — — — 241,810 241,811 233,656 220,457 214,701 210,588 10,210 5,763 2014 — — — — — 268,846 268,846 249,097 235,058 226,933 12,576 5,833 2015 — — — — — — 262,573 262,573 252,514 235,471 22,038 5,510 2016 — — — — — — — 250,491 250,491 241,406 19,874 5,378 2017 — — — — — — — — 244,094 244,098 9,887 5,178 2018 — — — — — — — — — 250,487 15,423 5,186 Total $ 2,142,468 $ 113,526 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, (Dollars in thousands) Accident Unaudited (1) Claim Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Frequency (2) 2009 $ 42,332 $ 96,173 $ 123,946 $ 142,667 $ 150,925 $ 155,365 $ 158,214 $ 159,345 $ 160,580 $ 162,253 19.82 2010 — 47,520 108,714 141,029 156,974 165,834 169,565 172,426 175,019 176,663 24.93 2011 — — 53,329 111,029 140,831 153,968 161,639 165,967 167,757 169,994 22.81 2012 — — — 50,579 107,467 133,658 149,161 154,553 157,207 159,807 18.73 2013 — — — — 51,396 119,507 150,304 165,994 172,479 177,724 16.54 2014 — — — — — 53,060 119,820 153,320 169,736 180,683 14.97 2015 — — — — — — 54,141 121,599 151,818 170,461 14.23 2016 — — — — — — — 52,238 115,713 143,016 14.19 2017 — — — — — — — — 56,951 122,552 14.58 2018 — — — — — — — — — 62,061 14.42 Total 1,525,214 All outstanding claim liabilities before 2008, net of reinsurance 73,939 Liabilities for claims and claim adjustment expenses, net of reinsurance 691,193 (1) Data presented for these calendar years is required supplementary information, which is unaudited. (2) Frequency, as calculated above, refers to reported claims divided by gross premium earned.
Summary of Average Annual Percentage Payout of Incurred Claims by Age Net of Reinsurance for Worker's Compensation and General Liability	The average annual percentage payout of incurred claims by age, net of reinsurance, for workers’ compensation and general liability as of December 31, 2018 is summarized below. Since workers’ compensation has long payout periods, the table below shows less than 100% in the years disclosed. This is required supplementary information, which is unaudited. Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Unaudited) Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Year 9 Year 10 24.6% 29.9% 14.6% 8.2% 4.1% 2.2% 1.4% 1.1% 0.8% 1.0%
Reconciliation of Beginning and Ending Reserve Balances, Net of Related Amounts Recoverable from Reinsurers	The following table provides a reconciliation of the beginning and ending reserve balances, net of related amounts recoverable from reinsurers, for 2018, 2017 and 2016: Year Ended December 31, 2018 2017 2016 (in thousands) Balance, beginning of period $ 771,845 $ 742,776 $ 718,033 Less amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 84,889 78,256 64,858 Net balance, beginning of period 686,956 664,520 653,175 Add incurred related to: Current accident year 250,487 244,094 250,337 Prior accident years (45,596 ) (34,770 ) (51,306 ) Total incurred 204,891 209,324 199,031 Less paid related to: Current accident year 62,061 56,951 52,085 Prior accident years 138,593 129,937 135,601 Total paid 200,654 186,888 187,686 Net balance, end of period 691,193 686,956 664,520 Add amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses 107,216 84,889 78,256 Balance, end of period $ 798,409 $ 771,845 $ 742,776
Summary Exposures to Various Asbestos Related Claims	The following table details our exposures to various asbestos related claims: Year Ended December 31, 2018 2017 2016 (in thousands) Reserves for loss and LAE at beginning of year $ 1,748 $ 1,487 $ 958 Incurred losses and LAE during the current year 108 556 816 Loss and LAE payments (301 ) (295 ) (287 ) Reserves for loss and LAE at end of year $ 1,555 $ 1,748 $ 1,487

Statutory Accounting and Regu_2

Statutory Accounting and Regulatory Requirements (Tables)	12 Months Ended
	Dec. 31, 2018
Insurance [Abstract]
Insurance Subsidiaries	Statutory-basis shareholders’ capital and surplus at December 31, 2018, 2017 and 2016 of the directly owned insurance subsidiary, AIIC, and the combined statutory-basis net income and realized investment gains for all AMERISAFE’s insurance subsidiaries for the three years in the period ended December 31, 2018, were as follows (in thousands): 2018 2017 2016 Capital and surplus $ 383,575 $ 382,062 $ 394,016 Net income 72,979 61,628 79,858 Net realized losses on investments (1,536 ) (647 ) (504 )

Stock Options and Restricted _2

Stock Options and Restricted Stock (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Option Activity	The following table summarizes information about the stock option activity under the 2005 Incentive Plan: Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Life (in years) Outstanding at January 1, 2016 88,879 12.10 4.3 Granted — — — Exercised (68,879 ) 12.14 3.3 Canceled, forfeited, or expired — — — Outstanding at December 31, 2016 20,000 8.71 3.1 Exercisable at December 31, 2016 20,000 8.71 3.1 Outstanding at January 1, 2017 20,000 8.71 3.1 Granted — — — Exercised — — — Canceled, forfeited, or expired — — — Outstanding at December 31, 2017 20,000 5.21 2.1 Exercisable at December 31, 2017 20,000 5.21 2.1 Outstanding at January 1, 2018 20,000 5.21 2.1 Granted — — — Exercised (15,000 ) 4.46 0.9 Canceled, forfeited, or expired — — — Outstanding at December 31, 2018 5,000 3.95 1.9 Exercisable at December 31, 2018 5,000 3.95 1.9
Weighted Average Grant Date Fair Values of Options Granted	2018 2017 2016 (in thousands) Cash received from option exercises $ 67 $ — $ 837 Total tax benefits realized for tax deductions from options exercised — — 833 Total intrinsic value of options exercised 766 — 2,967 Grant date fair value of options vested — — — Aggregate intrinsic value of vested options outstanding 264 1,128 1,073
Restricted Stock Activity	The following table summarizes information about the restricted stock activity under the 2005 Incentive Plan: Shares Weighted- Average Grant- Date Fair Value per Share Nonvested balance at January 1, 2016 1,600 27.35 Granted — — Vested (800 ) 27.35 Forfeited — — Nonvested balance at December 31, 2016 800 27.35 Granted — — Vested (800 ) 27.35 Forfeited — — Nonvested balance at December 31, 2017 — — Granted — — Vested — — Forfeited — — Nonvested balance at December 31, 2018 — — The following table summarizes information about the common and restricted stock activity under the 2012 Incentive Plan: Shares Weighted- AverageGrant- Date Fair Value per Share Nonvested balance at January 1, 2016 77,528 40.57 Granted 27,077 54.44 Vested (26,294 ) 45.18 Forfeited (1,919 ) — Nonvested balance at December 31, 2016 76,392 43.91 Granted 9,326 55.58 Vested (24,839 ) 43.89 Forfeited — — Nonvested balance at December 31, 2017 60,879 45.71 Granted 3,304 59.16 Vested (24,608 ) 44.31 Forfeited — — Nonvested balance at December 31, 2018 39,575 48.93 The following table summarizes information about the restricted stock activity under the Non-Employee Director Restricted Stock Plan: Shares Weighted- Average Grant- Date Fair Value per Share Nonvested balance at January 1, 2016 7,112 44.26 Granted 5,952 63.57 Vested (7,488 ) 44.54 Forfeited — — Nonvested balance at December 31, 2016 5,576 64.50 Granted 6,454 54.20 Vested (5,576 ) 64.50 Forfeited — — Nonvested balance at December 31, 2017 6,454 54.20 Granted 5,761 60.75 Vested (6,454 ) 54.20 Forfeited — — Nonvested balance at December 31, 2018 5,761 60.75

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Earnings Per Share	The calculation of basic and diluted EPS for the years ended December 31, 2018, 2017 and 2016 are presented below. For the Year Ended December 31, 2018 2017 2016 (in thousands, except earnings per share amounts) Basic EPS: Net income – basic $ 71,632 $ 46,231 $ 77,865 Basic weighted-average common shares 19,209 19,165 19,106 Basic earnings per share $ 3.73 $ 2.41 $ 4.08 Diluted EPS: Net income - diluted $ 71,632 $ 46,231 $ 77,865 Diluted weighted average common shares: Weighted average common shares 19,209 19,165 19,106 Stock options and restricted stock 84 81 98 Diluted weighted average common shares 19,293 19,246 19,204 Diluted earnings per common share $ 3.71 $ 2.40 $ 4.05
Reconciliation of Weighted Average Shares used for Basic and Diluted Earnings Per Share Calculation	The table below sets forth the reconciliation of the weighted average shares used for the basic and diluted EPS calculation. Years Ended 2018 2017 2016 Basic weighted average common shares 19,208,978 19,165,489 19,105,806 Add: Other common shares eligible for common dividends: Weighted average restricted shares and stock options (including tax benefit component) 84,104 80,377 97,844 Diluted weighted average common shares 19,293,082 19,245,866 19,203,650

Comprehensive Income and Accu_2

Comprehensive Income and Accumulated Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2018
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 (loss) for each period presented in the financial statements. Year Ended December 31, 2018 2017 2016 (in thousands) Beginning balance $ 3,612 $ (492 ) $ 2,587 Impact of adoption of ASU 2016-01 (615 ) — — Impact of adoption of ASU 2018-02 414 — — Adjusted beginning balance 3,411 (492 ) 2,587 Other comprehensive income (loss) before reclassification (4,551 ) 4,823 (3,231 ) Amounts reclassified from accumulated other comprehensive income (loss) 308 (719 ) 152 Net current period other comprehensive income (loss) (4,243 ) 4,104 (3,079 ) Ending balance $ (832 ) $ 3,612 $ (492 )
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 Comprehensive Income (Loss) Year Ended December 31, Affected line item in the statement of income 2018 2017 2016 (in thousands) Unrealized gains (losses) on available-for- sale securities $ (390 ) $ 1,106 $ (234 ) Net realized losses on investments (390 ) 1,106 (234 ) Income before income taxes 82 (387 ) 82 Income tax expense $ (308 ) $ 719 $ (152 ) Net income
Other Comprehensive Income	Pre-Tax Amount Tax Expense (Benefit) Net-of-Tax Amount (in thousands) December 31, 2018 Unrealized loss on securities: Unrealized loss on available-for-sale securities $ (5,760 ) $ (1,209 ) $ (4,551 ) Reclassification adjustment for gains realized in net income 390 82 308 Net unrealized loss (5,370 ) (1,127 ) (4,243 ) Other comprehensive loss $ (5,370 ) $ (1,127 ) $ (4,243 ) December 31, 2017 Unrealized gain on securities: Unrealized gain on available-for-sale securities $ 6,960 $ 2,137 $ 4,823 Reclassification adjustment for losses realized in net income (1,106 ) (387 ) (719 ) Net unrealized gain 5,854 1,750 4,104 Other comprehensive income $ 5,854 $ 1,750 $ 4,104 December 31, 2016 Unrealized loss on securities: Unrealized loss on available-for-sale securities $ (4,908 ) $ (1,718 ) $ (3,190 ) Less amortization of differences between fair value and amortized cost for fixed maturity security transfer (63 ) (22 ) (41 ) Reclassification adjustment for gains realized in net income 234 82 152 Net unrealized loss (4,737 ) (1,658 ) (3,079 ) Other comprehensive loss $ (4,737 ) $ (1,658 ) $ (3,079 )

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Fair Value of Annuities	The following table summarizes (in thousands) the fair value of the annuities at December 31, 2018, that the Company has purchased to satisfy its obligations. Life Insurance Company A.M. Best Rating Statement Value of Annuities Exceeding 1% of Statutory Surplus Pacific Life and Annuity Company A+ $ 18,028 American General Life Insurance Company A 14,802 New York Life Insurance Company A++ 10,335 Travelers Life and Annuity A 12,414 Metropolitan Life Insurance Company A+ 6,799 John Hancock Life Insurance Company A+ 7,153 Athene Annuity and Life Company A 4,638 United of Omaha Life Insurance Company A+ 5,435 Other 20,470 $ 100,074
Future Minimum Lease Payments	The Company leases equipment and office space under noncancelable operating leases. At December 31, 2018, future minimum lease payments are as follows (in thousands): 2019 $ 128 2020 118 2021 109 2022 110 2023 75 2024 6 $ 546

Concentration of Operations (Ta

Concentration of Operations (Tables)	12 Months Ended
	Dec. 31, 2018
Text Block [Abstract]
Net Premiums Earned for the Top Ten States	Net premiums earned during 2018, 2017 and 2016 for the top ten states in 2018 and all others are shown below: 2018 2017 2016 Dollars Percent Dollars Percent Dollars Percent (Dollars in thousands) Georgia $ 40,351 11.5 % $ 40,801 11.8 % $ 38,168 10.4 % Florida 39,672 11.3 % 34,615 10.0 % 29,051 7.9 % Pennsylvania 31,708 9.1 % 32,931 9.5 % 39,460 10.7 % Louisiana 25,810 7.4 % 25,422 7.3 % 30,426 8.3 % Illinois 19,710 5.6 % 22,169 6.4 % 25,796 7.0 % North Carolina 19,537 5.6 % 18,388 5.3 % 20,784 5.6 % Virginia 15,228 4.3 % 16,298 4.7 % 16,599 4.5 % Wisconsin 14,101 4.0 % 13,790 4.0 % 13,544 3.7 % South Carolina 13,924 4.0 % 13,327 3.9 % 13,897 3.8 % Minnesota 12,900 3.7 % 13,968 4.0 % 15,130 4.1 % All others 117,385 33.5 % 114,447 33.1 % 125,849 34.0 % Total net premiums earned $ 350,326 100.0 % $ 346,156 100.0 % $ 368,704 100.0 %

Fair Values of Financial Inst_2

Fair Values of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Carrying or Reported Values and Corresponding Fair Values for Financial Instruments	The following table summarizes the carrying or reported values and corresponding fair values for financial instruments: December 31, 2018 2017 Carrying Amount Fair Value Carrying Amount Fair Value (in thousands) Assets: Fixed maturity securities—held to maturity $ 613,878 $ 616,772 $ 629,668 $ 639,309 Fixed maturity securities—available-for-sale 478,730 478,730 465,594 465,594 Equity securities 18,651 18,651 9,282 9,282 Short-term investments 14,231 14,231 25,770 25,770 Cash and cash equivalents 40,344 40,344 55,559 55,559
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis	Assets and liabilities measured at fair value on a recurring basis as of December 31, 2018 and 2017 are as follows: 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 December 31, 2017 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 $ — $ 251,140 $ — $ 251,140 Corporate bonds — 130,222 — 130,222 U.S. agency-based mortgage-backed securities — 18,014 — 18,014 U.S. Treasury securities and obligations of U.S. government agencies 66,218 — — 66,218 Total available-for-sale—fixed maturity 66,218 399,376 — 465,594 Securities available-for-sale—equity: Domestic common stock 9,248 — 34 9,282 Total available-for-sale $ 75,466 $ 399,376 $ 34 $ 474,876
Schedule of Assets and Liabilities Measured at Amortized Cost	Assets and liabilities measured at amortized cost as of December 31, 2018 and 2017 are as follows: 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 December 31, 2017 Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (in thousands) Securities held-to-maturity—fixed maturity: States and political subdivisions $ — $ 469,101 $ — $ 469,101 Corporate bonds — 100,047 — 100,047 U.S. agency-based mortgage-backed securities — 10,845 — 10,845 U.S. Treasury securities 6,750 — — 6,750 Obligations of U.S. government agencies — 51,257 — 51,257 Asset-backed securities — 1,309 — 1,309 Total held-to-maturity $ 6,750 $ 632,559 $ — $ 639,309
Summary of Information Regarding Changes in Fair Value of Assets Measured at Fair Value	The following table presents summary information regarding changes in the fair value of assets measured at fair value using Level 3 input. Year Ended Twelve Months Ended December 31, 2018 December 31, 2017 (in thousands) Balance, beginning of period $ 34 $ — Transfer into Level 3 — 34 Unrealized loss on equity security (32 ) — Sale of equity security (2 ) Balance, end of period $ — $ 34

Quarterly Financial Data (Una_2

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Unaudited Quarterly Financial Data	The following table represents unaudited quarterly financial data for the years ended December 31, 2018 and 2017. Three Months Ended March 31 June 30 September 30 December 31 (in thousands, except per share amounts) 2018 Net premiums earned $ 87,310 $ 88,995 $ 85,184 $ 88,837 Net investment income 7,209 7,303 7,884 8,056 Net realized losses on investments (31 ) (1,111 ) (329 ) (65 ) Total revenues 94,175 95,380 93,529 94,669 Income before income taxes 19,414 20,930 24,460 22,777 Net income 16,169 16,956 19,701 18,806 Earnings per share: Basic $ 0.84 $ 0.88 $ 1.03 $ 0.98 Diluted $ 0.84 $ 0.88 $ 1.02 $ 0.98 Comprehensive income 10,321 17,109 17,582 22,176 Extraordinary cash dividends declared per common share $ — $ — $ — $ 3.50 Cash dividends declared per common share $ 0.22 $ 0.22 $ 0.22 $ 0.22 2017 Net premiums earned $ 90,912 $ 82,749 $ 85,118 $ 87,377 Net investment income 6,710 7,471 7,788 7,312 Net realized gains (losses) on investments (181 ) (388 ) (192 ) 114 Total revenues 97,542 89,925 92,804 94,937 Income before income taxes 18,733 22,151 23,556 17,800 Net income 13,524 15,481 16,577 649 Earnings per share: Basic $ 0.71 $ 0.81 $ 0.86 $ 0.03 Diluted $ 0.70 $ 0.81 $ 0.86 $ 0.03 Comprehensive income 14,476 17,437 17,194 1,228 Extraordinary cash dividends declared per common share $ — $ — $ — $ 3.50 Cash dividends declared per common share $ 0.20 $ 0.20 $ 0.20 $ 0.20

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule Of Accounting Policies [Line Items]
Percentage of comparable consolidated amounts		95.00%	95.00%	95.00%
Provisional amounts an increase in the deferred tax balance		$ 1,500,000
Original maturity of cash equivalent		90 days
Experience rated commission and other operating costs		$ 200,000	$ 200,000
Cash received, under reinsurance agreements			200,000
Commutation payment adjusted through offset against balance of funds			25,400,000
Advertising expense		$ 500,000	$ 500,000	$ 700,000
Assessment Related premium Payment period		1 year
Assessment Related loss Payment period		1 year
Buildings [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful life of assets		39 years
Limited Partnership [Member]
Schedule Of Accounting Policies [Line Items]
Unfunded commitments		$ 0
Minimum [Member]
Schedule Of Accounting Policies [Line Items]
Short-term investments maturity period		90 days
Minimum [Member] | Other Fixed Assets [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful life of assets		3 years
Maximum [Member]
Schedule Of Accounting Policies [Line Items]
Short-term investments maturity period		1 year
Maximum [Member] | Other Fixed Assets [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful life of assets		7 years
ASU 2016-01 [Member]
Schedule Of Accounting Policies [Line Items]
Decrease in net income	$ 390,000
ASU 2016-01 [Member] | Common Shares [Member]
Schedule Of Accounting Policies [Line Items]
Decrease to diluted earnings per common share	$ 0.02

Investments - Additional Inform

Investments - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018USD ($)Security	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Investment [Line Items]
Short-term investments	$ 14,231,000	$ 25,770,000
Sale of securities classified as held to maturity			$ 3,000,000
Gain of held-to-maturity investment securities			100,000
Individual fixed maturity held in unrealized loss position | Security	398
Individual fixed maturity held in unrealized loss position longer than 12 months | Security	323
Impairment losses recognized	$ 0	0	$ 0
Held-to-Maturity Securities [Member]
Investment [Line Items]
Investments on deposit with regulatory agencies	16,100,000
Available-for-Sale Securities [Member]
Investment [Line Items]
Investments on deposit with regulatory agencies	2,500,000
Corporate Bonds [Member]
Investment [Line Items]
Short-term investments	13,400,000
States and Political Subdivisions [Member]
Investment [Line Items]
Short-term investments	$ 800,000
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Short-term investments		$ 25,800,000

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	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	$ 613,878	$ 629,668
Held-to-Maturity, Gross Unrealized Gains	5,860	11,016
Held-to-Maturity, Gross Unrealized Losses	(2,966)	(1,375)
Held-to-Maturity, Fair Value	616,772	639,309
States and Political Subdivisions [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	445,922	460,428
Held-to-Maturity, Gross Unrealized Gains	5,109	9,628
Held-to-Maturity, Gross Unrealized Losses	(2,084)	(955)
Held-to-Maturity, Fair Value	448,947	469,101
Corporate Bonds [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	91,762	100,024
Held-to-Maturity, Gross Unrealized Gains	62	190
Held-to-Maturity, Gross Unrealized Losses	(455)	(167)
Held-to-Maturity, Fair Value	91,369	100,047
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	8,102	10,260
Held-to-Maturity, Gross Unrealized Gains	327	625
Held-to-Maturity, Gross Unrealized Losses	(80)	(40)
Held-to-Maturity, Fair Value	8,349	10,845
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	67,042	57,657
Held-to-Maturity, Gross Unrealized Gains	340	548
Held-to-Maturity, Gross Unrealized Losses	(339)	(198)
Held-to-Maturity, Fair Value	67,043	58,007
Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost, Totals	1,050	1,299
Held-to-Maturity, Gross Unrealized Gains	22	25
Held-to-Maturity, Gross Unrealized Losses	(8)	(15)
Held-to-Maturity, Fair Value	$ 1,064	$ 1,309

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	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Fixed maturity, Cost or Amortized Cost	$ 479,772	$ 461,236
Fixed maturity, Gross Unrealized Gains	3,758	7,072
Fixed maturity, Gross Unrealized Losses	(4,800)	(2,714)
Fixed maturity, Fair Value	478,730	465,594
Equity securities, Cost or Amortized Cost	19,962	8,503
Equity securities, Gross Unrealized Gains	30	779
Equity securities, Gross Unrealized Losses	(1,341)
Equity securities, Fair Value	18,651	9,282
Totals, Cost or Amortized Cost		469,739
Totals, Gross Unrealized Gains		7,851
Totals, Gross Unrealized Losses		(2,714)
Totals, Fair Value		474,876
States and Political Subdivisions [Member]
Investment [Line Items]
Fixed maturity, Cost or Amortized Cost	231,848	244,898
Fixed maturity, Gross Unrealized Gains	3,515	6,819
Fixed maturity, Gross Unrealized Losses	(2,118)	(577)
Fixed maturity, Fair Value	233,245	251,140
Corporate Bonds [Member]
Investment [Line Items]
Fixed maturity, Cost or Amortized Cost	173,904	130,210
Fixed maturity, Gross Unrealized Gains	243	224
Fixed maturity, Gross Unrealized Losses	(933)	(212)
Fixed maturity, Fair Value	173,214	130,222
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Fixed maturity, Cost or Amortized Cost	12,835	18,813
Fixed maturity, Gross Unrealized Losses	(320)	(799)
Fixed maturity, Fair Value	12,515	18,014
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Fixed maturity, Cost or Amortized Cost	61,185	67,315
Fixed maturity, Gross Unrealized Gains		29
Fixed maturity, Gross Unrealized Losses	(1,429)	(1,126)
Fixed maturity, Fair Value	$ 59,756	$ 66,218

Investments - Gross Unrealize_3

Investments - Gross Unrealized Gains and Losses and Cost of Equity (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Equity securities, Cost or Amortized Cost	$ 19,962	$ 8,503
Equity securities, Gross Unrealized Gains	30	779
Equity securities, Gross Unrealized Losses	(1,341)
Equity securities, Fair Value	18,651	$ 9,282
Domestic Common Stock [Member]
Investment [Line Items]
Equity securities, Cost or Amortized Cost	19,962
Equity securities, Gross Unrealized Gains	30
Equity securities, Gross Unrealized Losses	(1,341)
Equity securities, Fair Value	$ 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	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Within one year, Amortized Cost	$ 76,875
After one year through five years, Amortized Cost	256,614
After five years through ten years, Amortized Cost	81,311
After ten years, Amortized Cost	189,926
Held-to-maturity, Amortized Cost, Totals	613,878	$ 629,668
Within one year, Fair Value	76,861
After one year through five years, Fair Value	257,530
After five years through ten years, Fair Value	81,755
After ten years, Fair Value	191,213
Held-to-maturity, Fair Value, Totals	616,772	639,309
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost	8,102
Held-to-maturity, Amortized Cost, Totals	8,102	10,260
Held-to-maturity, Fair Value	8,349
Held-to-maturity, Fair Value, Totals	8,349	10,845
Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity, Amortized Cost	1,050
Held-to-maturity, Amortized Cost, Totals	1,050	1,299
Held-to-maturity, Fair Value	1,064
Held-to-maturity, Fair Value, Totals	$ 1,064	$ 1,309

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	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Within one year, Amortized Cost	$ 61,650
After one year through five years, Amortized Cost	175,743
After five years through ten years, Amortized Cost	47,058
After ten years, Amortized Cost	182,486
Fixed maturity, Cost or Amortized Cost	479,772	$ 461,236
Within one year, Fair Value	61,435
After one year through five years, Fair Value	174,213
After five years through ten years, Fair Value	46,725
After ten years, Fair Value	183,842
Total, Fair Value	478,730	465,594
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Available-for-sale securities, Amortized Cost	12,835
Fixed maturity, Cost or Amortized Cost	12,835	18,813
Available-for-sale securities, Fair value	12,515
Total, Fair Value	$ 12,515	$ 18,014

Investments - A Summary of the

Investments - A Summary of the Company's Realized Gains and Losses on Sales, Calls or Redemptions of Investments (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Proceeds from sales									$ 15,028	$ 27,764	$ 59,339
Gross realized investment gains									239	486	891
Gross realized investment (losses)									(1,354)	(5)	(1,728)
Net realized investment gains (losses)									(1,115)	481	(837)
Other, including gains (losses) on calls and redemptions									(421)	(1,128)	343
Net realized gains (losses) on investments	$ (65)	$ (329)	$ (1,111)	$ (31)	$ 114	$ (192)	$ (388)	$ (181)	(1,536)	(647)	(494)
Fixed Maturity Securities Available for Sale [Member]
Investment [Line Items]
Proceeds from sales									15,025	14,591	54,730
Gross realized investment gains									238	485	823
Gross realized investment (losses)									(1,354)	(5)	(1,728)
Net realized investment gains (losses)									(1,116)	480	(905)
Other, including gains (losses) on calls and redemptions									(144)	(520)	274
Net realized gains (losses) on investments									(1,260)	(40)	(631)
Equity Securities [Member]
Investment [Line Items]
Proceeds from sales									3	1
Gross realized investment gains									1	1
Net realized investment gains (losses)									1	1
Net realized gains (losses) on investments									1	1
Other [Member]
Investment [Line Items]
Proceeds from sales										13,172	4,609
Gross realized investment gains											68
Net realized investment gains (losses)											68
Other, including gains (losses) on calls and redemptions									(277)	(608)	69
Net realized gains (losses) on investments									$ (277)	$ (608)	$ 137

Investments - Major Categories

Investments - Major Categories of the Company's Net Investment Income (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investment [Line Items]
Total gross investment income									$ 31,418	$ 30,383	$ 29,753
Investment expenses									(966)	(1,102)	(1,647)
Net investment income	$ 8,056	$ 7,884	$ 7,303	$ 7,209	$ 7,312	$ 7,788	$ 7,471	$ 6,710	30,452	29,281	28,106
Fixed Maturity Securities Available for Sale [Member]
Investment [Line Items]
Total gross investment income									28,762	28,961	27,837
Equity Securities [Member]
Investment [Line Items]
Total gross investment income									448	201
Short-term Investments [Member]
Investment [Line Items]
Total gross investment income									$ 2,208	1,117	348
Other Investments [Member]
Investment [Line Items]
Total gross investment income										$ 104	$ 1,568

Investments - Investment Securi

Investments - Investment Securities Continuous Unrealized Loss Position (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months	$ 48,682	$ 218,074
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months	99	972
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	278,163	28,931
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	2,867	403
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	326,845	247,005
Held-to-maturity securities, Gross Unrealized Losses, Total	2,966	1,375
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months	75,208	135,576
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months	360	520
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	218,832	76,085
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	4,440	2,194
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	294,040	211,661
Available-for Sale, Gross Unrealized Losses, Total	4,800	2,714
Fair Value of Investments with Unrealized Losses, Less Than 12 months	123,890	353,650
Gross Unrealized Loss, Less Than 12 Months	459	1,492
Fair Value of Investments with Unrealized Losses, 12 Months or Greater	496,995	105,016
Gross Unrealized Losses, 12 Months or Greater	7,307	2,597
Fair Value of Investments with Unrealized Losses, Total	620,885	458,666
Gross Unrealized Losses, Total	7,766	4,089
States and Political Subdivisions [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months	28,369	110,698
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months	59	654
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	180,550	19,895
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	2,025	301
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	208,919	130,593
Held-to-maturity securities, Gross Unrealized Losses, Total	2,084	955
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months	16,109	23,365
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months	81	86
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	76,255	19,153
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	2,037	491
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	92,364	42,518
Available-for Sale, Gross Unrealized Losses, Total	2,118	577
Corporate Bonds [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months	17,448	56,425
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months	36	156
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	48,315	4,121
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	419	11
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	65,763	60,546
Held-to-maturity securities, Gross Unrealized Losses, Total	455	167
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months	59,099	82,795
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months	279	171
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	70,306	5,888
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	654	41
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	129,405	88,683
Available-for Sale, Gross Unrealized Losses, Total	933	212
U.S. Agency-Based Mortgage-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Less Than 12 Months		2,798
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months		40
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	2,287
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	80
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	2,287	2,798
Held-to-maturity securities, Gross Unrealized Losses, Total	80	40
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months		14,686
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months		59
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	12,515	3,328
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	320	740
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	12,515	18,014
Available-for Sale, Gross Unrealized Losses, Total	320	799
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	48,153
Held-to-maturity securities, Gross Unrealized Losses, Less Than 12 Months	4	122
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	46,486	3,948
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	335	76
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	49,351	52,101
Held-to-maturity securities, Gross Unrealized Losses, Total	339	198
Available-for Sale, Fair value of Investments with Unrealized Losses, Less Than 12 Months		14,730
Available-for Sale, Gross Unrealized Losses, Less Than 12 Months		204
Available-for Sale, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	59,756	47,716
Available-for Sale, Gross Unrealized Losses, 12 Months or Greater	1,429	922
Available-for Sale, Fair Value of Investments with Unrealized Losses, Total	59,756	62,446
Available-for Sale, Gross Unrealized Losses, Total	1,429	1,126
Asset-Backed Securities [Member]
Investment [Line Items]
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, 12 Months or Greater	525	967
Held-to-maturity securities, Gross Unrealized Losses, 12 Months or Greater	8	15
Held-to-maturity securities, Fair Value of Investments with Unrealized Losses, Total	525	967
Held-to-maturity securities, Gross Unrealized Losses, Total	$ 8	$ 15

Premiums Receivable - Component

Premiums Receivable - Components of Premiums Receivable (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Premiums Receivable, Net [Abstract]
Premiums receivable	$ 167,868	$ 179,460
Allowance for doubtful accounts	(5,390)	(5,226)	$ (5,212)	$ (4,852)
Premiums receivable, net	$ 162,478	$ 174,234

Premiums Receivable - Summary o

Premiums Receivable - Summary of Activity in Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Premiums Receivable, Allowance for Doubtful Accounts [Roll Forward]
Balance, beginning of year	$ 5,226	$ 5,212	$ 4,852
Provision for bad debts	883	1,394	1,646
Write-offs	(719)	(1,380)	(1,286)
Balance, end of year	$ 5,390	$ 5,226	$ 5,212

Premiums Receivable - Additiona

Premiums Receivable - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Premiums Receivable, Net [Abstract]
Earned but Unbilled	$ 7.5	$ 6.3	$ 7.7

Deferred Policy Acquisition C_3

Deferred Policy Acquisition Costs - Schedule of Major Categories of the Deferred Policy Acquisition Costs (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Charges Insurers [Abstract]
Agents’ commissions	$ 14,953	$ 15,238
Premium taxes	3,161	3,395
Deferred underwriting expenses	1,620	1,618
Total deferred policy acquisition costs	$ 19,734	$ 20,251	$ 19,300	$ 20,412

Deferred Policy Acquisition C_4

Deferred Policy Acquisition Costs - Schedule of Activity in the Deferred Policy Acquisition Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance, beginning of year	$ 20,251	$ 19,300	$ 20,412
Policy acquisition costs deferred	45,252	43,960	43,209
Amortization expense during the year	(45,769)	(43,009)	(44,321)
Balance, end of year	$ 19,734	$ 20,251	$ 19,300

Property and Equipment - Schedu

Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 21,361	$ 21,221
Accumulated depreciation	(15,103)	(15,093)
Property and equipment, net	6,258	6,128
Land and Office Building [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	7,798	7,713
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	6,150	6,578
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	7,339	6,856
Automobiles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 74	$ 74

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Abstract]
Property and equipment held under capital lease	$ 200,000	$ 200,000	$ 200,000
Accumulated depreciation	$ 120,000	$ 58,000	$ 80,000

Property and Equipment - Sche_2

Property and Equipment - Schedule of Future Minimum Lease Payments for Capital Lease Obligations (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Property Plant And Equipment [Abstract]
2,019	$ 47
2,020	48
2,021	4
Present value of net minimum lease payments	$ 99

Reinsurance - Schedule of the E

Reinsurance - Schedule of the Effect of Reinsurance on Premiums Written and Earned (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Premiums Written and Earned [Abstract]
Gross Written									$ 351,696	$ 350,267	$ 373,055
Ceded Written									(9,344)	(8,869)	(10,307)
Net premiums Written									342,352	341,398	362,748
Gross Earned									359,670	355,025	379,011
Ceded Earned									(9,344)	(8,869)	(10,307)
Net premiums Earned	$ 88,837	$ 85,184	$ 88,995	$ 87,310	$ 87,377	$ 85,118	$ 82,749	$ 90,912	$ 350,326	$ 346,156	$ 368,704

Reinsurance - Schedule of the A

Reinsurance - Schedule of the Amounts Recoverable from Reinsurers (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Unpaid losses recoverable:
Case basis	$ 76,525	$ 66,061
Incurred but not reported	30,691	18,828
Paid losses recoverable	325	554
Experience-rated commissions recoverable	4,465	4,690
Total reinsurance recoverables	$ 112,006	$ 90,133

Reinsurance - Additional Inform

Reinsurance - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Insurance [Abstract]
Paid losses recoverable outstanding due date	90 days
Paid losses recoverable past due	$ 0
Received reinsurance recoveries	$ 1,300,000	$ 1,600,000	$ 500,000
Unsecured reinsurance recoverable by reinsurer reporting threshold	1.50%

Reinsurance - Schedule of Unsec

Reinsurance - Schedule of Unsecured Reinsurance Recoverables from Reinsurers (Detail) - USD ($) $ in Thousands		Dec. 31, 2018	Dec. 31, 2017
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers		$ 112,006	$ 90,133
Funds withheld and letters of credit related to the above recoverables		(69,932)
Total unsecured amounts recoverable from reinsurers		42,074
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers		112,006
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Hannover Reinsurance (Ireland) Limited [Member] | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers	[1]	53,609
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Allianz Risk Transfer AG (Bermuda) [Member] | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers	[1]	13,084
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Odyssey America Reinsurance Corporation [Member] | A.M. Best Rating, A [Member]
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers		11,754
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Minnesota Workers’ Compensation Reinsurance Association [Member]
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers	[1]	8,823
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Other Reinsurers [Member]
Ceded Credit Risk [Line Items]
Amounts recoverable from reinsurers		$ 24,736
[1]	Current participant in our 2019 reinsurance program.

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Company's Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets:
Discounting of net unpaid loss and loss adjustment expenses	$ 21,377	$ 8,830
Unearned premiums	8,069	8,466
Accrued expenses and other	2,636	2,359
State income tax	855	782
Accrued policyholder dividends	2,188	1,918
Impaired securities	21	42
Capital loss carryforward		190
Accrued insurance-related assessments	3,139	3,256
Net unrealized loss on securities	496
Total deferred tax assets	38,781	25,843
Deferred income tax liabilities:
Deferred policy acquisition costs	(5,207)	(5,317)
Callable bond amortization	(5)	(8)
Unrealized gain on securities available-for-sale		(1,070)
Property and equipment and other	(178)	(3)
Salvage and subrogation	(719)	(183)
Loss reserves adjustment due to the Tax Act	(10,820)
Total deferred income tax liabilities	(16,929)	(6,581)
Net deferred income taxes	$ 21,852	$ 19,262

Income Taxes - Components of Co

Income Taxes - Components of Consolidated Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current:
Federal	$ 16,407	$ 22,477	$ 35,602
State	1,004	732	1,603
Total Current	17,411	23,209	37,205
Deferred:
Federal	(1,389)	12,965	(2,120)
State	(73)	(165)	(129)
Total Deferred	(1,462)	12,800	(2,249)
Income tax expense, Total	$ 15,949	$ 36,009	$ 34,956

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Valuation allowance	$ 0	$ 0	$ 0	$ 0
U.S. federal income tax statutory rate	21.00%	21.00%	35.00%	35.00%
Revaluation of net deferred income tax assets	$ 12,600,000		$ 12,620,000
Uncertain tax positions		$ 0	$ 0	$ 0

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense from Operations from the Amount Computed by Applying the U.S. Federal Income Tax Statutory Rate of 35% to Income Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income tax computed at federal statutory tax rate		$ 18,392	$ 28,784	$ 39,487
Tax-exempt interest, net		(2,965)	(5,707)	(5,370)
State income tax		720	311	913
Dividends received deduction		(44)	(48)	(125)
Revaluation of net deferred income tax assets	$ 12,600		12,620
Other		(154)	49	51
Income tax expense, Total		$ 15,949	$ 36,009	$ 34,956

Line of Credit - Additional Inf

Line of Credit - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Maximum amount of line of credit	$ 20,000,000
Line of credit facility expiration date	Dec. 31, 2019
Outstanding borrowings or letters of credit	$ 0	$ 0
Line of Credit Facility Expired December 2019 [Member]
Line of Credit Facility [Line Items]
Payment on unused portion of the loan	0.25%
Total fee	$ 50,000

Loss and Loss Adjustment Expe_3

Loss and Loss Adjustment Expenses - Development Tables of Incurred and Paid Claims and Allocated Claim Adjustment Expenses Net of Reinsurance (Detail) $ in Thousands		12 Months Ended
		Dec. 31, 2018USD ($)Claim	Dec. 31, 2017USD ($)		Dec. 31, 2016USD ($)		Dec. 31, 2015USD ($)		Dec. 31, 2014USD ($)		Dec. 31, 2013USD ($)		Dec. 31, 2012USD ($)		Dec. 31, 2011USD ($)		Dec. 31, 2010USD ($)		Dec. 31, 2009USD ($)
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 2,142,468
Total IBNR Plus Expected Development on Reported Claims		113,526
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		1,525,214
All outstanding claim liabilities before 2008, net of reinsurance		73,939
Liabilities for claims and claim adjustment expenses, net of reinsurance		691,193
Accident Year 2009 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	174,731	$ 177,015		$ 176,586		$ 177,795		$ 182,274		$ 184,006		$ 187,943		$ 188,462		$ 188,746		$ 185,359
Total IBNR Plus Expected Development on Reported Claims		$ 3,407
Cumulative Number of Claims Reported | Claim		5,372
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 162,253	160,580	[1]	159,345	[1]	158,214	[1]	155,365	[1]	150,925	[1]	142,667	[1]	123,946	[1]	96,173	[1]	$ 42,332	[1]
Claim Frequency	[2]	19.82%
Accident Year 2010 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 189,040	189,403		191,000		193,029		198,861		205,769		208,035		202,479		179,156
Total IBNR Plus Expected Development on Reported Claims		$ 5,612
Cumulative Number of Claims Reported | Claim		5,970
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 176,663	175,019	[1]	172,426	[1]	169,565	[1]	165,834	[1]	156,974	[1]	141,029	[1]	108,714	[1]	$ 47,520	[1]
Claim Frequency	[2]	24.93%
Accident Year 2011 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 189,327	191,126		192,988		195,262		198,213		199,163		199,522		196,384
Total IBNR Plus Expected Development on Reported Claims		$ 7,045
Cumulative Number of Claims Reported | Claim		6,043
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 169,994	167,757	[1]	165,967	[1]	161,639	[1]	153,968	[1]	140,831	[1]	111,029	[1]	$ 53,329	[1]
Claim Frequency	[2]	22.81%
Accident Year 2012 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 180,387	182,859		184,460		193,515		212,738		222,075		222,549
Total IBNR Plus Expected Development on Reported Claims		$ 7,454
Cumulative Number of Claims Reported | Claim		5,749
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 159,807	157,207	[1]	154,553	[1]	149,161	[1]	133,658	[1]	107,467	[1]	$ 50,579	[1]
Claim Frequency	[2]	18.73%
Accident Year 2013 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 210,588	214,701		220,457		233,656		241,811		241,810
Total IBNR Plus Expected Development on Reported Claims		$ 10,210
Cumulative Number of Claims Reported | Claim		5,763
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 177,724	172,479	[1]	165,994	[1]	150,304	[1]	119,507	[1]	$ 51,396	[1]
Claim Frequency	[2]	16.54%
Accident Year 2014 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 226,933	235,058		249,097		268,846		268,846
Total IBNR Plus Expected Development on Reported Claims		$ 12,576
Cumulative Number of Claims Reported | Claim		5,833
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 180,683	169,736	[1]	153,320	[1]	119,820	[1]	$ 53,060	[1]
Claim Frequency	[2]	14.97%
Accident Year 2015 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 235,471	252,514		262,573		262,573
Total IBNR Plus Expected Development on Reported Claims		$ 22,038
Cumulative Number of Claims Reported | Claim		5,510
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 170,461	151,818	[1]	121,599	[1]	$ 54,141	[1]
Claim Frequency	[2]	14.23%
Accident Year 2016 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 241,406	250,491		250,491
Total IBNR Plus Expected Development on Reported Claims		$ 19,874
Cumulative Number of Claims Reported | Claim		5,378
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 143,016	115,713	[1]	$ 52,238	[1]
Claim Frequency	[2]	14.19%
Accident Year 2017 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 244,098	244,094
Total IBNR Plus Expected Development on Reported Claims		$ 9,887
Cumulative Number of Claims Reported | Claim		5,178
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 122,552	$ 56,951	[1]
Claim Frequency	[2]	14.58%
Accident Year 2018 [Member]
Claims Development [Line Items]
Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance	[1]	$ 250,487
Total IBNR Plus Expected Development on Reported Claims		$ 15,423
Cumulative Number of Claims Reported | Claim		5,186
Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance		$ 62,061
Claim Frequency	[2]	14.42%
[1]	Data presented for these calendar years is required supplementary information, which is unaudited
[2]	Frequency, as calculated above, refers to reported claims divided by gross premium earned

Loss and Loss Adjustment Expe_4

Loss and Loss Adjustment Expenses - Summary of Average Annual Percentage Payout Of Incurred Claims By Age Net of Reinsurance For Worker's Compensation and general Liability (Unaudited) (Detail)	Dec. 31, 2018
Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net [Abstract]
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 1	24.60%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 2	29.90%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 3	14.60%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 4	8.20%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 5	4.10%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 6	2.20%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 7	1.40%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 8	1.10%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 9	0.80%
Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance, Year 10	1.00%

Loss and Loss Adjustment Expe_5

Loss and Loss Adjustment Expenses - Reconciliation of Beginning and Ending Reserve Balances, Net of Related Amounts Recoverable from Reinsurers (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Roll Forward In Liability For Unpaid Claims And Claims Adjustment Expense [Abstract]
Balance, beginning of period	$ 771,845	$ 742,776	$ 718,033
Less amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses	84,889	78,256	64,858
Net balance, beginning of period	686,956	664,520	653,175
Add incurred related to:
Current accident year	250,487	244,094	250,337
Prior accident years	(45,596)	(34,770)	(51,306)
Total incurred	204,891	209,324	199,031
Less paid related to:
Current accident year	62,061	56,951	52,085
Prior accident years	138,593	129,937	135,601
Total paid	200,654	186,888	187,686
Net balance, end of period	691,193	686,956	664,520
Add amounts recoverable from reinsurers on unpaid loss and loss adjustment expenses	107,216	84,889	78,256
Balance, end of period	$ 798,409	$ 771,845	$ 742,776

Loss and Loss Adjustment Expe_6

Loss and Loss Adjustment Expenses - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Unpaid Losses And Loss Expenses [Line Items]
Loss and LAE Related to Prior Periods	$ 45,596	$ 34,770	$ 51,306
Accident Year 2014 [Member]
Unpaid Losses And Loss Expenses [Line Items]
Loss and LAE Related to Prior Periods	8,100
Accident Year 2015 [Member]
Unpaid Losses And Loss Expenses [Line Items]
Loss and LAE Related to Prior Periods	17,000
Accident Year 2016 [Member]
Unpaid Losses And Loss Expenses [Line Items]
Loss and LAE Related to Prior Periods	$ 9,100

Loss and Loss Adjustment Expe_7

Loss and Loss Adjustment Expenses - Summary Exposures to Various Asbestos Related Claims (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Asbestos Claims [Line Items]
Balance, beginning of period	$ 771,845	$ 742,776	$ 718,033
Incurred losses and LAE during the current year	204,891	209,324	199,031
Loss and LAE payments	(62,061)	(56,951)	(52,085)
Balance, end of period	798,409	771,845	742,776
Asbestos Issue [Member]
Asbestos Claims [Line Items]
Balance, beginning of period	1,748	1,487	958
Incurred losses and LAE during the current year	108	556	816
Loss and LAE payments	(301)	(295)	(287)
Balance, end of period	$ 1,555	$ 1,748	$ 1,487

Statutory Accounting and Regu_3

Statutory Accounting and Regulatory Requirements - Insurance Subsidiaries (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Insurance [Abstract]
Capital and surplus	$ 383,575	$ 382,062	$ 394,016
Net income	72,979	61,628	79,858
Net realized losses on investments	$ (1,536)	$ (647)	$ (504)

Statutory Accounting and Regu_4

Statutory Accounting and Regulatory Requirements - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Insurance [Abstract]
Dividends to the Company	10.00%
Dividends paid	$ 65.4	$ 78.9	$ 67
Dividends permissible to pay without seeking regulatory approval	$ 71

Capital Stock - Additional Info

Capital Stock - Additional Information (Detail) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Equity [Abstract]
Common stock, shares authorized	50,000,000	50,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares issued	20,528,230	20,504,165
Common stock, shares outstanding	19,269,980	19,245,915
Preferred stock, shares authorized	10,000,000
Preferred stock, par value	$ 0.01
Preferred stock, shares outstanding	0

Stock Options and Restricted _3

Stock Options and Restricted Stock - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018USD ($)Companyshares	Dec. 31, 2017USD ($)shares	Dec. 31, 2016USD ($)shares	Dec. 31, 2013USD ($)	Dec. 31, 2015shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total tax expense			$ 995,000
2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration for Stock option grants exercisable	10 years
Expiration of stock option	90 days
Unexercised portion of stock option remains exercisable	1 year
Number of companies used for the estimation of expected volatility | Company	6
Dividend yield assumed	0.00%
Cash dividends paid				$ 0
Compensation expense	$ 12,000	$ 56,000	58,000
Total tax expense	$ 0	$ 0	$ 110,000
2005 Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock outstanding | shares			800		1,600
2012 Equity and Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under incentive plan | shares	500,000
Common stock granted | shares	3,304	7,434
Common stock available for future awards | shares	343,147
2012 Equity and Incentive Compensation Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted | shares		1,892
2012 Equity and Incentive Compensation Plan [Member] | Share Based Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 726,000	$ 884,000	$ 849,000
2012 Equity and Incentive Compensation Plan [Member] | Long-Term Incentive Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	976,000	724,000	334,000
Non-Employee Director Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	351,000	355,000	361,000
Total tax expense	$ 0	$ 0	$ 52,000
Shares authorized under incentive plan | shares	150,000
Common stock granted | shares	5,761	6,454	5,952
Common stock available for future awards | shares	57,907
Restricted stock award for a number of shares	$ 50,000
Restricted stock outstanding | shares	5,761	6,454	5,576		7,112
Non-Employee Director Restricted Stock Plan [Member] | Restricted Stock [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in annual restricted stock award	$ 75,000

Stock Options and Restricted _4

Stock Options and Restricted Stock - Stock Option Activity (Detail) - 2005 Incentive Plan [Member] - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding, Beginning balance	20,000	20,000	88,879
Shares, Granted	0	0	0
Shares, Exercised	(15,000)	0	(68,879)
Shares Canceled, forfeited, or expired	0	0	0
Shares outstanding, Ending balance	5,000	20,000	20,000	88,879
Shares exercisable, Ending balance	5,000	20,000	20,000
Weighted- Average Exercise Price, Beginning balance	$ 5.21	$ 8.71	$ 12.10
Weighted- Average Exercise Price, Granted	0	0	0
Weighted- Average Exercise Price, Exercised	4.46	0	12.14
Weighted- Average Exercise Price, Canceled, forfeited, or expired	0	0	0
Weighted- Average Exercise Price, Ending balance	3.95	5.21	8.71	$ 12.10
Weighted- Average Exercise Price, Exercisable Ending balance	$ 3.95	$ 5.21	$ 8.71
Weighted- Average Remaining Contractual Life (in years)	1 year 10 months 24 days	2 years 1 month 6 days	3 years 1 month 6 days	4 years 3 months 18 days
Weighted- Average Remaining Contractual Life (in years), Exercised	10 months 24 days		3 years 3 months 18 days
Weighted- Average Remaining Contractual Life (in years), Exercisable	1 year 10 months 24 days	2 years 1 month 6 days	3 years 1 month 6 days

Stock Options and Restricted _5

Stock Options and Restricted Stock - Weighted Average Grant Date Fair Values of Options Granted (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Cash received from option exercises	$ 67		$ 837
Total tax benefits realized for tax deductions from options exercised			833
Total intrinsic value of options exercised	766		2,967
Aggregate intrinsic value of vested options outstanding	$ 264	$ 1,128	$ 1,073

Stock Options and Restricted _6

Stock Options and Restricted Stock - Restricted Stock Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
2005 Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Nonvested outstanding, Beginning balance		800	1,600
Shares, Vested		(800)	(800)
Shares, Nonvested outstanding, Ending balance			800
Weighted-Average Grant-Date Fair Value per Share, Beginning balance		$ 27.35	$ 27.35
Weighted-Average Grant-Date Fair Value per Share, Vested		$ 27.35	27.35
Weighted-Average Grant-Date Fair Value per Share, Ending balance			$ 27.35
2012 Incentive Plan [Member] | Common and Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Nonvested outstanding, Beginning balance	60,879	76,392	77,528
Shares, Granted	3,304	9,326	27,077
Shares, Vested	(24,608)	(24,839)	(26,294)
Shares, Forfeited			(1,919)
Shares, Nonvested outstanding, Ending balance	39,575	60,879	76,392
Weighted-Average Grant-Date Fair Value per Share, Beginning balance	$ 45.71	$ 43.91	$ 40.57
Weighted-Average Grant-Date Fair Value per Share, Granted	59.16	55.58	54.44
Weighted-Average Grant-Date Fair Value per Share, Vested	44.31	43.89	45.18
Weighted-Average Grant-Date Fair Value per Share, Ending balance	$ 48.93	$ 45.71	$ 43.91
Non-Employee Director Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Nonvested outstanding, Beginning balance	6,454	5,576	7,112
Shares, Granted	5,761	6,454	5,952
Shares, Vested	(6,454)	(5,576)	(7,488)
Shares, Nonvested outstanding, Ending balance	5,761	6,454	5,576
Weighted-Average Grant-Date Fair Value per Share, Beginning balance	$ 54.20	$ 64.50	$ 44.26
Weighted-Average Grant-Date Fair Value per Share, Granted	60.75	54.20	63.57
Weighted-Average Grant-Date Fair Value per Share, Vested	54.20	64.50	44.54
Weighted-Average Grant-Date Fair Value per Share, Ending balance	$ 60.75	$ 54.20	$ 64.50

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								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share Basic [Abstract]
Net income – basic	$ 18,806	$ 19,701	$ 16,956	$ 16,169	$ 649	$ 16,577	$ 15,481	$ 13,524	$ 71,632	$ 46,231	$ 77,865
Basic weighted-average common shares									19,208,978	19,165,489	19,105,806
Basic earnings per share	$ 0.98	$ 1.03	$ 0.88	$ 0.84	$ 0.03	$ 0.86	$ 0.81	$ 0.71	$ 3.73	$ 2.41	$ 4.08
Net income - diluted									$ 71,632	$ 46,231	$ 77,865
Weighted average common shares									19,208,978	19,165,489	19,105,806
Stock options and restricted stock									84,104	80,377	97,844
Diluted weighted average common shares									19,293,082	19,245,866	19,203,650
Diluted earnings per common share	$ 0.98	$ 1.02	$ 0.88	$ 0.84	$ 0.03	$ 0.86	$ 0.81	$ 0.70	$ 3.71	$ 2.40	$ 4.05

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Weighted Average Shares used for Basic and Diluted Earnings Per Share Calculation (Detail) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Basic weighted average common shares	19,208,978	19,165,489	19,105,806
Add: Other common shares eligible for common dividends:
Weighted average restricted shares and stock options (including tax benefit component)	84,104	80,377	97,844
Diluted weighted average common shares	19,293,082	19,245,866	19,203,650

Comprehensive Income and Accu_3

Comprehensive Income and Accumulated Other Comprehensive Income - Schedule of Changes in Accumulated Other Comprehensive Income (AOCI) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 425,423	$ 456,150	$ 453,981
Net current period other comprehensive income (loss)	(4,243)	4,104	(3,079)
Ending Balance	409,762	425,423	456,150
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	3,612	(492)	2,587
Adjusted beginning balance	3,411	(492)	2,587
Other comprehensive income (loss) before reclassification	(4,551)	4,823	(3,231)
Amounts reclassified from accumulated other comprehensive income (loss)	308	(719)	152
Net current period other comprehensive income (loss)	(4,243)	4,104	(3,079)
Ending Balance	(832)	$ 3,612	$ (492)
Accumulated Other Comprehensive Income (Loss) [Member] | ASU 2016-01 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Impact of adoption of ASU	(615)
Accumulated Other Comprehensive Income (Loss) [Member] | ASU 2018-02 [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Impact of adoption of ASU	$ 414

Comprehensive Income and Accu_4

Comprehensive Income and Accumulated Other Comprehensive Income - Reclassification Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Unrealized gains (losses) on available-for-sale securities	$ (65)	$ (329)	$ (1,111)	$ (31)	$ 114	$ (192)	$ (388)	$ (181)	$ (1,536)	$ (647)	$ (494)
Income before income taxes	22,777	24,460	20,930	19,414	17,800	23,556	22,151	18,733	87,581	82,240	112,821
Income tax expense									(15,949)	(36,009)	(34,956)
Net income	$ 18,806	$ 19,701	$ 16,956	$ 16,169	$ 649	$ 16,577	$ 15,481	$ 13,524	71,632	46,231	77,865
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]
Unrealized gains (losses) on available-for-sale securities									(390)	1,106	(234)
Income before income taxes									(390)	1,106	(234)
Income tax expense									82	(387)	82
Net income									$ (308)	$ 719	$ (152)

Comprehensive Income and Accu_5

Comprehensive Income and Accumulated Other Comprehensive Income - Other Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income Loss Net Of Tax [Abstract]
Unrealized gain (loss) on available-for-sale securities, Pre-Tax Amount	$ (5,760)	$ 6,960	$ (4,908)
Less amortization of differences between fair value and amortized cost for fixed maturity security transfer, Pre-Tax Amount			(63)
Reclassification adjustment for gains (losses) realized in net income, Pre-Tax Amount	390	(1,106)	234
Net unrealized gain loss, Pre-Tax Amount	(5,370)	5,854	(4,737)
Other comprehensive income (loss), Pre-Tax Amount	(5,370)	5,854	(4,737)
Unrealized gain loss on available-for-sale securities, Tax Expense (Benefit)	(1,209)	2,137	(1,718)
Less amortization of differences between fair value and amortized cost for fixed maturity security transfer, Tax Expense (Benefit)			(22)
Reclassification adjustment for gains (losses) realized in net income, Tax Expense (Benefit)	82	(387)	82
Net unrealized gain loss, Tax Expense (Benefit)	(1,127)	1,750	(1,658)
Other comprehensive income (loss), Tax Expense (Benefit)	(1,127)	1,750	(1,658)
Unrealized gain (loss) on available-for-sale securities, Net-of-Tax Amount	(4,551)	4,823	(3,190)
Less amortization of differences between fair value and amortized cost for fixed maturity security transfer, Net-of-Tax Amount			(41)
Reclassification adjustment for gains (losses) realized in net income, Net-of-Tax Amount	308	(719)	152
Net unrealized gain loss, Net-of-Tax Amount	(4,243)	4,104	(3,079)
Other comprehensive income (loss), Net-of-Tax Amount	$ (4,243)	$ 4,104	$ (3,079)

Employee Benefit Plan - Additio

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Compensation And Retirement Disclosure [Abstract]
Defined contribution plan name	401(k) benefit plan
Matches employee compensation for participating employees	3.00%
Fully vested in employer contributions	5 years
Defined contribution this plan	$ 0.7	$ 0.6	$ 0.4

Commitments and Contingencies -

Commitments and Contingencies - Fair Value of Annuities (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	$ 100,074
Pacific Life and Annuity Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	18,028
American General Life Insurance Company [Member] | A.M. Best Rating, A [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	14,802
New York Life Insurance Company [Member] | A.M. Best Rating, A++ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	10,335
Travelers Life and Annuity [Member] | A.M. Best Rating, A [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	12,414
Metropolitan Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	6,799
John Hancock Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	7,153
Athene Annuity and Life Company [Member] | A.M. Best Rating, A [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	4,638
United of Omaha Life Insurance Company [Member] | A.M. Best Rating, A+ [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	5,435
Other [Member]
Commitments And Contingencies [Line Items]
Statement value of annuities exceeding 1% of statutory surplus	$ 20,470

Commitments and Contingencies_2

Commitments and Contingencies - Future Minimum Lease Payments (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Operating Leases Future Minimum Payments Due [Abstract]
2,019	$ 128
2,020	118
2,021	109
2,022	110
2,023	75
2,024	6
Total future minimum lease payments	$ 546

Commitments and Contingencies_3

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Rent expense	$ 0.2	$ 0.1	$ 0.2

Concentration of Operations - N

Concentration of Operations - Net Premiums Earned for the Top Ten States (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned	$ 88,837	$ 85,184	$ 88,995	$ 87,310	$ 87,377	$ 85,118	$ 82,749	$ 90,912	$ 350,326	$ 346,156	$ 368,704
Premium earned percentage									100.00%	100.00%	100.00%
Georgia [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 40,351	$ 40,801	$ 38,168
Premium earned percentage									11.50%	11.80%	10.40%
Florida [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 39,672	$ 34,615	$ 29,051
Premium earned percentage									11.30%	10.00%	7.90%
Pennsylvania [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 31,708	$ 32,931	$ 39,460
Premium earned percentage									9.10%	9.50%	10.70%
Louisiana [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 25,810	$ 25,422	$ 30,426
Premium earned percentage									7.40%	7.30%	8.30%
Illinois [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 19,710	$ 22,169	$ 25,796
Premium earned percentage									5.60%	6.40%	7.00%
North Carolina [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 19,537	$ 18,388	$ 20,784
Premium earned percentage									5.60%	5.30%	5.60%
Virginia [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 15,228	$ 16,298	$ 16,599
Premium earned percentage									4.30%	4.70%	4.50%
Minnesota [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 12,900	$ 13,968	$ 15,130
Premium earned percentage									3.70%	4.00%	4.10%
Wisconsin [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 14,101	$ 13,790	$ 13,544
Premium earned percentage									4.00%	4.00%	3.70%
South Carolina [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 13,924	$ 13,327	$ 13,897
Premium earned percentage									4.00%	3.90%	3.80%
All Others [Member]
Schedule Of Premiums Earned Net By Segment [Line Items]
Net premiums earned									$ 117,385	$ 114,447	$ 125,849
Premium earned percentage									33.50%	33.10%	34.00%

Fair Values of Financial Inst_3

Fair Values of Financial Instruments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held to maturity, carrying value	$ 613,878,000	$ 629,668,000
Fair Value, Measurements, Nonrecurring [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held to maturity, carrying value	11,000
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Recognized impairment	100,000
Securities held to maturity, fair value	31,000
Limited Partnership [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Unfunded commitments	$ 0

Fair Values of Financial Inst_4

Fair Values of Financial Instruments - Summary of Carrying or Reported Values and Corresponding Fair Values for Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities—held to maturity	$ 613,878	$ 629,668
Fixed maturity securities—held to maturity	616,772	639,309
Fixed maturity securities—available-for-sale	478,730	465,594
Equity securities	18,651	9,282
Short-term investments	14,231	25,770
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities—held to maturity	616,772	639,309
Fixed maturity securities—available-for-sale	478,730	465,594
Equity securities	18,651	9,282
Short-term investments	14,231	25,770
Cash and cash equivalents	40,344	55,559
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed maturity securities—available-for-sale	478,730	465,594
Equity securities	18,651	9,282
Short-term investments	14,231	25,770
Cash and cash equivalents	$ 40,344	$ 55,559

Fair Values of Financial Inst_5

Fair Values of Financial Instruments - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	$ 478,730	$ 465,594
Equity securities, Fair Value	18,651	9,282
Total		474,876
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	478,730	465,594
Total	497,381	474,876
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	18,651	9,282
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	233,245	251,140
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	173,214	130,222
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	12,515	18,014
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	59,756	66,218
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	59,756	66,218
Total	78,407	75,466
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Common Stock [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities, Fair Value	18,651	9,248
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	59,756	66,218
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	418,974	399,376
Total	418,974	399,376
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [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	233,245	251,140
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Available-for-sale—fixed maturity, Fair Value	173,214	130,222
Fair Value, Measurements, Recurring [Member] | 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]
Available-for-sale—fixed maturity, Fair Value	$ 12,515	18,014
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total		34
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Common Stock [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Equity securities, Fair Value		$ 34

Fair Values of Financial Inst_6

Fair Values of Financial Instruments - Schedule of Assets and Liabilities Measured at Amortized Cost (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	$ 616,772	$ 639,309
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	7,111	6,750
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	609,661	632,559
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	448,947	469,101
States and Political Subdivisions [Member] | 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	448,947	469,101
Corporate Bonds [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Securities held-to-maturity-fixed maturity, Fair Value	91,369	100,047
Corporate Bonds [Member] | 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	91,369	100,047
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	8,349	10,845
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]
Securities held-to-maturity-fixed maturity, Fair Value	8,349	10,845
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	7,111	6,750
U.S. Treasury Securities [Member] | 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	7,111	6,750
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	59,932	51,257
Obligations of U.S. Government Agencies [Member] | 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	59,932	51,257
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	1,064	1,309
Asset-Backed Securities [Member] | 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	$ 1,064	$ 1,309

Fair Values of Financial Inst_7

Fair Values of Financial Instruments - Summary of Information Regarding Changes in Fair Value of Assets Measured at Fair Value (Detail) - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Balance, beginning of period	$ 34
Transfer into Level 3		$ 34
Unrealized loss on equity security	(32)
Sale of equity security	$ (2)
Balance, end of period		$ 34

Quarterly Financial Data (Una_3

Quarterly Financial Data (Unaudited) - Unaudited Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Net premiums earned	$ 88,837	$ 85,184	$ 88,995	$ 87,310	$ 87,377	$ 85,118	$ 82,749	$ 90,912	$ 350,326	$ 346,156	$ 368,704
Net investment income	8,056	7,884	7,303	7,209	7,312	7,788	7,471	6,710	30,452	29,281	28,106
Net realized gains (losses) on investments	(65)	(329)	(1,111)	(31)	114	(192)	(388)	(181)	(1,536)	(647)	(494)
Total revenues	94,669	93,529	95,380	94,175	94,937	92,804	89,925	97,542	377,753	375,208	396,662
Income before income taxes	22,777	24,460	20,930	19,414	17,800	23,556	22,151	18,733	87,581	82,240	112,821
Net income	$ 18,806	$ 19,701	$ 16,956	$ 16,169	$ 649	$ 16,577	$ 15,481	$ 13,524	$ 71,632	$ 46,231	$ 77,865
Earnings per share:
Basic	$ 0.98	$ 1.03	$ 0.88	$ 0.84	$ 0.03	$ 0.86	$ 0.81	$ 0.71	$ 3.73	$ 2.41	$ 4.08
Diluted	$ 0.98	$ 1.02	$ 0.88	$ 0.84	$ 0.03	$ 0.86	$ 0.81	$ 0.70	$ 3.71	$ 2.40	$ 4.05
Comprehensive income	$ 22,176	$ 17,582	$ 17,109	$ 10,321	$ 1,228	$ 17,194	$ 17,437	$ 14,476	$ 67,389	$ 50,335	$ 74,786
Extraordinary cash dividends declared per common share	$ 3.50				$ 3.50				$ 3.50	$ 3.50	$ 3.25	$ 3	$ 1.50	$ 0
Cash dividends declared per common share	$ 0.22	$ 0.22	$ 0.22	$ 0.22	$ 0.20	$ 0.20	$ 0.20	$ 0.20	$ 0.88	$ 0.80	$ 0.72

Capital Management - Additional

Capital Management - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 31, 2016
Equity [Abstract]
Share repurchase program, new limit amount									$ 25,000,000
Shares repurchased under the program			0
Shares repurchased	1,258,250	1,258,250	1,258,250	1,258,250
Shares repurchased, value	$ 22,370,000	$ 22,370,000	$ 22,370,000	$ 22,370,000
Shares repurchased, average price			$ 17.78
Quarterly dividend per share	$ 0.22	$ 0.20	0.22	$ 0.20	$ 0.18	$ 0.15	$ 0.12	$ 0.08
Extraordinary dividends declared per share	$ 3.50	$ 3.50	$ 3.50	$ 3.50	$ 3.25	$ 3	$ 1.50	$ 0

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - $ / shares	Feb. 26, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Subsequent Event [Line Items]
Cash dividend per share			$ 0.22	$ 0.20	$ 0.18	$ 0.15	$ 0.12	$ 0.08
Scenario, Forecast [Member]
Subsequent Event [Line Items]
Expected cash dividend per share		$ 1
Subsequent Event [Member] | Dividend Declared [Member]
Subsequent Event [Line Items]
Cash dividend per share	$ 0.25
Date of payment to shareholders entitled to dividends	Mar. 22, 2019
Date of record of shareholders entitled to dividends	Mar. 8, 2019

Schedule II. Condensed Financ_2

Schedule II. Condensed Financial Information of Registrant - Condensed Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets
Equity securities, at fair value (cost $10,007 and $8,503 in 2018 and 2017, respectively)	$ 18,651	$ 9,282
Short-term investments	14,231	25,770
Total investments	1,125,490	1,130,314
Cash and cash equivalents	40,344	55,559	$ 58,936	$ 69,481
Deferred income taxes	21,852	19,262
Property and equipment, net	6,258	6,128
Federal income tax recoverable		1,761
Other assets	17,572	9,959
Total assets	1,515,931	1,518,236
Liabilities, redeemable preferred stock and shareholders’ equity
Total liabilities	1,106,169	1,092,813
Shareholders' equity (net of Treasury stock of $22,370 at December 31, 2018 and 2017)	409,762	425,423	456,150	453,981
Total liabilities and shareholders’ equity	1,515,931	1,518,236
Parent Company [Member]
Assets
Equity securities, at fair value (cost $10,007 and $8,503 in 2018 and 2017, respectively)	9,803	9,248
Short-term investments		7,962
Investment in subsidiaries	388,797	386,844
Total investments	398,600	404,054
Cash and cash equivalents	5,509	16,351	$ 9,596	$ 26,968
Deferred income taxes	509	302
Notes receivable from subsidiaries	3,270	1,711
Property and equipment, net	1,536	1,359
Federal income tax recoverable	2,995
Other assets	800	4,412
Total assets	413,219	428,189
Liabilities, redeemable preferred stock and shareholders’ equity
Total liabilities	3,457	2,766
Shareholders' equity (net of Treasury stock of $22,370 at December 31, 2018 and 2017)	409,762	425,423
Total liabilities and shareholders’ equity	$ 413,219	$ 428,189

Schedule II. Condensed Financ_3

Schedule II. Condensed Financial Information of Registrant - Condensed Balance Sheets (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Condensed Balance Sheet Statements, Captions [Line Items]
Equity securities, cost	$ 19,962	$ 8,503
Net of Treasury stock	22,370	22,370
Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Equity securities, cost	10,007	8,503
Net of Treasury stock	$ 22,370	$ 22,370

Schedule II. Condensed Financ_4

Schedule II. Condensed Financial Information of Registrant - Condensed Statements of Income (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues
Net investment income	$ 8,056	$ 7,884	$ 7,303	$ 7,209	$ 7,312	$ 7,788	$ 7,471	$ 6,710	$ 30,452	$ 29,281	$ 28,106
Net unrealized losses on equity securities									(2,088)
Fee and other income									599	418	346
Total revenues	94,669	93,529	95,380	94,175	94,937	92,804	89,925	97,542	377,753	375,208	396,662
Expenses
Total expenses									290,172	292,968	283,841
Income tax expense (benefit)									15,949	36,009	34,956
Net income	$ 18,806	$ 19,701	$ 16,956	$ 16,169	$ 649	$ 16,577	$ 15,481	$ 13,524	71,632	46,231	77,865
Parent Company [Member]
Revenues
Net investment income									1,089	679	1,509
Net unrealized losses on equity securities									(948)
Fee and other income									7,389	6,890	5,843
Total revenues									7,530	7,569	7,352
Expenses
Other operating costs									7,530	7,569	7,352
Total expenses									7,530	7,569	7,352
Income tax expense (benefit)									(36)	125	(156)
Gain (loss) before equity in earnings of subsidiaries									36	(125)	156
Equity in net income of subsidiaries									71,596	46,356	77,709
Net income									$ 71,632	$ 46,231	$ 77,865

Schedule II. Condensed Financ_5

Schedule II. Condensed Financial Information of Registrant - Condensed Statements of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities
Net cash provided by operating activities	$ 98,268	$ 130,810	$ 114,212
Investing activities
Purchases of property and equipment	(1,126)	(478)	(1,638)
Net cash used in investing activities	(29,059)	(51,542)	(50,478)
Financing activities
Proceeds from stock option exercises	67		837
Tax benefit from share-based payments			995
Dividends to shareholders	(84,491)	(82,645)	(76,111)
Net cash used in financing activities	(84,424)	(82,645)	(74,279)
Change in cash and cash equivalents	(15,215)	(3,377)	(10,545)
Cash and cash equivalents at beginning of year	55,559	58,936	69,481
Cash and cash equivalents at end of year	40,344	55,559	58,936
Parent Company [Member]
Operating activities
Net cash provided by operating activities	2,448	15,138	2,771
Investing activities
Purchases of investments	(47,825)	(37,361)	(11,940)
Proceeds from sales of investments	54,600	33,000
Purchases of property and equipment	(1,041)	(277)	(924)
Dividends from subsidiary	65,400	78,900	67,000
Net cash used in investing activities	71,134	74,262	54,136
Financing activities
Proceeds from stock option exercises	67		837
Tax benefit from share-based payments			995
Dividends to shareholders	(84,491)	(82,645)	(76,111)
Net cash used in financing activities	(84,424)	(82,645)	(74,279)
Change in cash and cash equivalents	(10,842)	6,755	(17,372)
Cash and cash equivalents at beginning of year	16,351	9,596	26,968
Cash and cash equivalents at end of year	$ 5,509	$ 16,351	$ 9,596

Schedule VI. Supplemental Inf_2

Schedule VI. Supplemental Information Concerning Property-Casualty Insurance Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Information For Property Casualty Insurance Underwriters [Abstract]
Deferred Policy Acquisition Costs	$ 19,734	$ 20,251	$ 19,300
Reserves for Unpaid Loss and Loss Adjustment Expense	798,409	771,845	742,776
Unearned Premium	149,296	157,270	162,028
Net Premiums Earned	350,326	346,156	368,704
Net Investment Income	30,452	29,281	28,106
Loss and LAE Related to Current Period	250,487	244,094	250,337
Loss and LAE Related to Prior Periods	(45,596)	(34,770)	(51,306)
Amortization of Deferred Policy Acquisition Costs	(45,769)	(43,009)	(44,321)
Paid Claims and Claim Adjustment Expenses	200,654	186,888	187,686
Net Premiums Written	$ 342,352	$ 341,398	$ 362,748