Kinsale Capital (KNSL) 10-K 23 Feb 24 2023 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2023	Feb. 16, 2024	Jun. 30, 2023
Document and Entity Information [Abstract]
Entity Registrant Name	KINSALE CAPITAL GROUP, INC.
Trading Symbol	KNSL
Entity Listing, Description	Common Stock, par value $0.01 per share
Entity Address, Address Line One	2035 Maywill Street
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Richmond
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	23230
City Area Code	804
Local Phone Number	289-1300
Entity Incorporation, State or Country Code	DE
Entity Central Index Key	0001669162
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-37848
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		23,189,095
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Public Float			$ 8,197,188,903
Security Exchange Name	NYSE
Entity Tax Identification Number	98-0664337
ICFR Auditor Attestation Flag	true
Auditor Name	KPMG LLP
Auditor Location	Richmond, VA
Auditor Firm ID	185
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement relating to its 2024 annual meeting of stockholders (the "2024 Proxy Statement") are incorporated by reference into Part III of this Annual Report on Form 10-K. The 2024 Proxy Statement will be filed with the Securities and Exchange Commission within 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.
Document Financial Statement Error Correction [Flag]	true
Document Financial Statement Restatement Recovery Analysis [Flag]	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Investments:
Fixed-maturity securities available-for-sale, at fair value (amortized cost: $2,834,463 allowance for credit loss: $553 – 2023; $1,933,632 and $366 – 2022)	$ 2,711,759	$ 1,760,100
Equity securities, at fair value (cost: $193,543 – 2023; $126,478 – 2022)	234,813	152,471
Real Estate Investments, Net	14,791	76,387
Short-Term Investments	5,589	41,337
Total investments	2,966,952	2,030,295
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	126,694	156,274
Investment income due and accrued	21,689	14,451
Premiums and fees receivable, net of allowance for credit losses of $13,383 in 2023 and $8,067 in 2022	143,212	105,754
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	247,836	220,454
Ceded unearned premiums	52,516	42,935
Deferred policy acquisition costs, net of ceding commissions	88,395	61,594
Intangible assets	3,538	3,538
Deferred income tax asset, net	55,699	56,983
Other assets	66,443	54,844
Total assets	3,772,974	2,747,122
Liabilities:
Gross reserves for unpaid losses and loss adjustment expenses, beginning of year	1,692,875	1,238,402
Unearned premiums	701,351	499,677
Payable to reinsurers	47,582	32,024
Accounts payable and accrued expenses	44,922	31,361
Long-Term Debt	183,846	195,747
Other liabilities	15,566	4,462
Total liabilities	2,686,142	2,001,673
Contingencies
Stockholders' equity:
Common stock, $0.01 par value, 400,000,000 shares authorized, 23,181,919 shares issued and outstanding at December 31, 2023; 23,090,526 shares issued and outstanding at December 31, 2022	232	231
Additional paid-in capital	352,970	347,015
Retained earnings	828,247	533,121
Accumulated other comprehensive loss	(94,617)	(134,918)
Stockholders' equity	1,086,832	745,449
Total liabilities and stockholders' equity	$ 3,772,974	$ 2,747,122
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares outstanding (in shares)	23,181,919	23,090,526
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	$ 553	$ 366

Consolidated Balance Sheets - (

Consolidated Balance Sheets - (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Investments:
Amortized cost	$ 2,834,463	$ 1,933,632
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	553	366
Equity securities - cost	193,543	126,478
Allowance for credit losses	13,383	8,067
Reinsurance Recoverable, Allowance for Credit Loss	$ 744	$ 459
Stockholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	23,181,919	23,090,526
Common stock, shares outstanding (in shares)	23,181,919	23,090,526

Consolidated Statements of Inco

Consolidated Statements of Income and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Gross written premiums	$ 1,568,815	$ 1,102,092	$ 764,373
Ceded written premiums	(304,185)	(165,282)	(104,164)
Net written premiums	1,264,630	936,810	660,209
Change in unearned premiums	(192,093)	(142,691)	(77,330)
Net earned premiums	1,072,537	794,119	582,879
Insurance Fee Income	27,026	19,604	13,693
Net investment income	102,335	51,282	31,048
Change in the fair value of equity securities	15,277	(27,723)	22,812
Change in allowance for credit losses on investments	(187)	(366)	0
Net realized investment gains	6,040	1,191	2,828
Other income	1,421	697	212
Total revenues	1,224,449	838,804	653,472
Expenses:
Losses and loss adjustment expenses	600,219	457,913	324,415
Underwriting, acquisition and insurance expenses	228,970	180,322	138,593
Interest expense	10,301	4,284	994
Other expenses	942	721	669
Total expenses	840,432	643,240	464,671
Income before income taxes	384,017	195,564	188,801
Income tax expense	75,924	36,450	36,142
Net income	308,093	159,114	152,659
Other comprehensive income (loss):
Change in unrealized gains (losses) on available-for-sale investments, net of taxes	40,301	(153,043)	(23,255)
Total comprehensive income	$ 348,394	$ 6,071	$ 129,404
Earnings per share:
Basic	$ 13.37	$ 6.97	$ 6.73
Diluted	$ 13.22	$ 6.88	$ 6.62
Weighted-average common shares outstanding:
Basic	23,045	22,815	22,693
Diluted	23,307	23,125	23,062

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance, shares at Dec. 31, 2020		22,757,251
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation, shares		90,084
Restricted shares withheld for taxes, shares		(12,958)
Balance, shares at Dec. 31, 2021		22,834,377
Balance at Dec. 31, 2020	$ 576,238	$ 228	$ 291,315	$ 243,315	$ 41,380
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock under stock-based compensation plan	982	0	982
Stock-based compensation expense	4,844		4,844
Restricted shares withheld for taxes	(2,101)		(2,101)
Dividends declared	(10,032)			(10,032)
Other comprehensive income (loss), net of income tax	(23,255)				(23,255)
Net income	152,659			152,659
Balance at Dec. 31, 2021	$ 699,335	$ 228	295,040	385,942	18,125
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued, shares	155,000
Stock-based compensation, shares		116,140
Restricted shares withheld for taxes, shares		(14,991)
Balance, shares at Dec. 31, 2022	23,090,526	23,090,526
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net of issuance costs	$ 47,498	$ 2	47,496
Issuance of stock under stock-based compensation plan	1,090	1	1,089
Stock-based compensation expense	6,678		6,678
Restricted shares withheld for taxes	(3,288)		(3,288)
Dividends declared	(11,935)			(11,935)
Other comprehensive income (loss), net of income tax	(153,043)				(153,043)
Net income	159,114			159,114
Balance at Dec. 31, 2022	$ 745,449	$ 231	347,015	533,121	(134,918)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued, shares
Stock-based compensation, shares		104,949
Restricted shares withheld for taxes, shares		(13,556)
Balance, shares at Dec. 31, 2023	23,181,919	23,181,919
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net of issuance costs	$ 0
Issuance of stock under stock-based compensation plan	877	1	876
Stock-based compensation expense	9,361		9,361
Restricted shares withheld for taxes	(4,282)		(4,282)
Dividends declared	(12,967)			(12,967)
Other comprehensive income (loss), net of income tax	40,301				40,301
Net income	308,093			308,093
Balance at Dec. 31, 2023	$ 1,086,832	$ 232	$ 352,970	$ 828,247	$ (94,617)

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Stockholders' Equity (Parentheticals) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Stockholders' Equity [Abstract]
Dividends declared, per share	$ 0.56	$ 0.52	$ 0.44

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities:
Net income	$ 308,093	$ 159,114	$ 152,659
Adjustments to reconcile net income to net cash provided by operating activities:
Change in fair value of equity securities	(15,277)	27,723	(22,812)
Net investment gains	(6,040)	(1,191)	(2,828)
Change in allowance for credit losses on investments	187	366	0
Deferred tax (benefit) expense	(9,429)	(14,191)	(576)
Depreciation and amortization	3,274	2,721	2,308
Stock compensation expense	9,361	6,678	4,844
Change in operating assets and liabilities:
Investment income due and accrued	(7,238)	(6,793)	(1,021)
Premiums receivable, net	(37,458)	(34,750)	(22,363)
Reserves for unpaid loss and loss adjustment expenses	454,473	357,058	245,331
Unearned premiums	201,674	151,947	86,744
Reinsurance balances, net	(21,405)	(90,828)	(35,729)
Deferred policy acquisition costs	(26,801)	(19,626)	(10,056)
Income taxes (recoverable) payable	742	7,518	(3,882)
Accounts payable and accrued expenses	12,519	8,111	10,102
Other	(6,840)	3,958	4,321
Net cash provided by operating activities	859,835	557,815	407,042
Investing Activities:
Purchase of property and equipment	(6,607)	(6,901)	(5,920)
Purchase of real estate investment	(2,116)	(76,623)	0
Sale of property and equipment	62,036	0	0
Payments for (Proceeds from) Short-Term Investments	36,706	(40,638)	0
Purchases - fixed-maturity securities	(1,317,048)	(751,402)	(654,922)
Purchases - equity securities	(86,605)	(11,506)	(24,867)
Sales - fixed-maturity securities	245,618	63,092	113,006
Sales - equity securities	30,623	4,990	4,617
Maturities and calls - fixed-maturity securities	176,501	110,415	216,131
Net cash used in investing activities	(860,892)	(708,573)	(351,955)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	0	47,498	0
Proceeds from Lines of Credit	0	73,000	0
Repayments of Long-Term Lines of Credit	(62,000)	(43,000)	0
Debt issuance costs	(164)	(2,381)	0
Proceeds from Issuance of Long-Term Debt	50,000	125,000	0
Payroll taxes withheld and remitted on share-based payments	(4,282)	(3,288)	(2,101)
Common stock issued, stock options exercised	877	1,090	982
Dividends paid	(12,954)	(11,927)	(10,021)
Net cash provided by (used in) financing activities	(28,523)	185,992	(11,140)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Beginning Balance	156,274	121,040	77,093
Net change in cash and cash equivalents	(29,580)	35,234	43,947
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 126,694	$ 156,274	$ 121,040

Description of business

Description of business	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of business	Description of business

Summary of significant accounti

Summary of significant accounting policies	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Summary of significant accounting policies	Summary of significant accounting policies Principles of consolidation The accompanying consolidated financial statements include the accounts of Kinsale Capital Group, Inc. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Certain prior year amounts have been reclassified to conform to the current year's presentation. Use of estimates The preparation of consolidated financial statements in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities, if any, at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Management periodically reviews its estimates and assumptions. These reviews include evaluating the adequacy of reserves for unpaid losses and loss adjustment expenses, allowance for credit losses and uncollectible reinsurance, fair value of investments, as well as evaluating the investment portfolio for credit impairments. Cash and cash equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. Short-term investments Short-term investments are carried at amortized cost, which approximates fair value. Short-term investments have maturities greater than three months but less than one year at the date of purchase. Fixed-maturity and equity securities Fixed-maturity securities are classified as available-for-sale and reported at fair value. Unrealized gains and losses on these securities are excluded from earnings but are recorded as a separate component of other comprehensive income and stockholders' equity, net of deferred income taxes. Equity securities are reported at fair value. Changes in unrealized gains and losses in fair value of these investments are recognized in net income. The Company regularly reviews all its available-for-sale investments with unrealized losses to assess whether the decline in the fair value is deemed to be a credit loss. See Note 2 for further discussion regarding the determination of credit losses. Interest on fixed-maturity securities is credited to earnings as it accrues. Premiums and discounts are amortized or accreted using the effective interest method over the lives of the related fixed maturities, or to the earliest call date for securities purchased at a premium. This method includes an adjustment for estimated principal prepayments, if any, on asset- and mortgage-backed securities. To the extent that the estimated lives of such securities change as a result of changes in estimated prepayment rates, the adjustments are included in net investment income using the retrospective method. Dividends on equity securities are included in earnings on the ex-dividend date. Realized gains and losses on disposition of investments are based on specific identification of the investments sold on the trade date. Real estate investments Real estate investments include real estate and the related assets purchased for investment purposes. Real estate and the related depreciable assets are carried at cost, net of accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful life of the assets and is included in net investment income. Rental income is recognized on a straight-line basis over the term of the respective lease and is included in net investment income. Land is not depreciated. Real estate is evaluated for impairment when events or circumstances indicate the carrying value of the real estate may not be recoverable. Reinsurance Reinsurance premiums, commissions, and ceded unearned premiums on reinsured business are accounted for on a basis consistent with that used in accounting for the original policies issued and the terms of the reinsurance contracts. The Company receives ceding commissions in accordance with certain reinsurance treaties. The ceding commissions are capitalized and amortized as a reduction of underwriting, acquisition and insurance expenses. Reinsurance recoverables represent paid losses and loss adjustment expenses and reserves for unpaid losses and loss adjustment expenses ceded to reinsurers that are subject to reimbursement under reinsurance treaties. The method for determining reinsurance recoverables for unpaid losses and loss adjustment expenses involves reviewing actuarial estimates of gross unpaid losses and loss adjustment expenses to determine the Company's ability to cede unpaid losses and loss adjustment expenses under the Company's existing reinsurance contracts. This method is continually reviewed and updated and any resulting adjustments are reflected in earnings in the period identified. See Note 8 for a further discussion of the Company's reinsurance program. Premiums receivable, net Premiums receivable balances are carried at face value, net of any allowance for credit losses. The allowance for credit losses represents an estimate of amounts considered uncollectible based on the Company’s assessment of the collectability of receivables that are past due. The estimate considers historical loss data, current and future economic conditions and specific identification of collectability concerns where applicable. The following table presents the rollforward of the allowance for credit losses for premiums receivable for the years ended December 31, 2023 and 2022: Year Ended December 31, 2023 2022 (in thousands) Beginning balance $ 8,067 $ 3,391 Current period change for estimated uncollectible premiums 9,790 5,988 Write-offs of uncollectible premiums receivable (4,474) (1,312) Ending balance $ 13,383 $ 8,067 Deferred policy acquisition costs, net of ceding commissions The Company defers commissions, net of ceding commissions, and certain other costs that are directly related to the successful acquisition of insurance contracts. All eligible costs are capitalized and charged to expense in proportion to premium earned over the estimated policy life. To the extent that unearned premiums on existing policies are not adequate to cover the related costs and expenses, referred to as a premium deficiency, deferred policy acquisition costs are charged to earnings. The Company considers anticipated investment income in determining whether a premium deficiency exists. Property and equipment, net Property and equipment are stated at cost less accumulated depreciation. Depreciation of property and equipment is calculated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives range from 39 years for the building and parking deck, 15 to 20 years for land improvements, 7 to 10 years for furniture and equipment, and 3 to 7 years for electronic data processing hardware and software. Property and equipment are included in other assets in the accompanying consolidated balance sheets and consists of the following: December 31, 2023 2022 (in thousands) Building $ 37,181 $ 33,065 Parking deck 5,072 5,072 Land 3,068 3,068 Equipment 3,958 3,444 Software 15,375 11,410 Furniture and fixtures 3,065 2,615 Leasehold improvements 153 — Land improvements 474 474 Construction in progress - building 6,623 2,618 74,969 61,766 Accumulated depreciation (11,565) (8,291) Total property and equipment, net $ 63,404 $ 53,475 Indefinite-lived intangible assets Indefinite-lived intangible assets are recorded at fair value at the date of acquisition. The Company's indefinite-lived intangible assets are comprised solely of regulatory approvals granted by the various state insurance departments to write insurance business in the respective states on a non-admitted basis. In accordance with U.S. GAAP, amortization of indefinite-lived intangible assets is not permitted. Indefinite-lived intangible assets are tested for impairment during the fourth quarter on an annual basis, or earlier if there is reason to suspect that their values may have been diminished or impaired. There were no impairments recognized in December 31, 2023, 2022, or 2021. In addition, as of December 31, 2023, no triggering events occurred that suggested an updated review was necessary. Reserves for unpaid losses and loss adjustment expenses Reserves for unpaid losses and loss adjustment expenses represent management's best estimate of ultimate unpaid cost of all reported and unreported losses and loss adjustment expenses incurred prior to the financial statement date. The estimates are based on an actuarial method that uses management’s initial expected loss ratios, expected reporting patterns for losses based on industry data and the Company’s actual reported losses and loss adjustment expenses. All estimates are regularly reviewed and, as experience develops and new information becomes known, the reserves for unpaid losses and loss adjustment expenses are adjusted as necessary. Such adjustments are reflected in the results of operations in the period in which they are determined. Although management believes that the reserves for losses and loss adjustment expenses are reasonable, due to the inherent uncertainty in estimating reserves for unpaid losses and loss adjustment expenses, it is possible that the Company’s actual incurred losses and loss adjustment expenses will not develop in a manner consistent with the assumptions inherent in the determination of these reserves. If actual liabilities exceed recorded amounts, there will be an increase to the Company’s reserves resulting in a reduction in net income and stockholders’ equity in the period in which the deficiency is identified. Furthermore, management may determine that recorded reserves are more than adequate to cover expected losses which will result in a reduction to the reserves. The Company believes that the reserves for unpaid losses and loss adjustment expenses at December 31, 2023 and 2022 are adequate and represent a reasonable estimate of the Company's future obligations. See Note 7 for a further discussion of reserves for unpaid losses and loss adjustment expenses. Revenue recognition Premiums are recognized as revenue ratably over the term of the insurance contracts, net of ceded reinsurance. Unearned premiums are calculated on a daily pro rata basis. Fee income is recognized as revenue when the related premium is written. Income taxes Deferred income tax assets and liabilities are determined based on the differences between the recorded amounts and the tax bases of assets and liabilities, using enacted tax rates expected to be in effect during the year in which the basis differences reverse. The effect on deferred taxes of a change in tax rates is recognized in income in the period in which such change was enacted. Valuation allowances on deferred tax assets are estimated based on the Company's assessment of the realizability of such amounts. Valuation allowances are recorded when it is more likely than not that some portion, or all, of the deferred tax assets will not be realizable. The Company provides for uncertain tax positions, and the related interest and penalties, based upon management’s assessment of whether a tax benefit is more likely than not to be sustained upon examination by tax authorities. To the extent that the anticipated tax outcome of these uncertain tax positions changes, such changes in estimate will impact the income tax provision in the period in which such determination is made. The Company recognizes accrued interest and penalties related to uncertain tax positions as a component of income tax expense. The Company uses the portfolio approach to release stranded tax effects in accumulated other comprehensive income ("AOCI") related to its available-for-sale fixed-maturity securities. Under this approach, stranded tax effects remaining in AOCI are released only when the entire portfolio of the available-for-sale fixed-maturity securities are liquidated, sold or extinguished. Contingencies Liabilities for loss contingencies, arising from noninsurance policy claims, assessments, litigation, fines, and penalties and other sources, are recorded when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred. Fair value of financial instruments Fair value is estimated for each class of financial instrument based on the framework established in the fair value accounting guidance. This guidance requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Fair value hierarchy disclosures are based on the quality of inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). See Note 3 for further details regarding fair value disclosures. Stock-based compensation Stock-based compensation is expensed based upon the estimated fair value of employee stock awards. Compensation cost for awards of equity instruments to employees is measured based on the grant-date fair value of those awards and compensation expense is recognized over the service period that the awards vest. Forfeitures of stock-based compensation awards are recognized as they occur. See Note 9 for further discussion and related disclosures regarding stock-based compensation. Recently adopted accounting pronouncements There were no recently adopted accounting standards that had a material impact on the Company’s consolidated financial statements. Prospective accounting pronouncements ASU 2023-07, Segment Reporting - Improvements to Reportable Segment Disclosures In November 2023, the FASB issued ASU 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures," which expands reportable segment disclosure requirements by requiring disclosures of significant reportable segment expenses that are regularly provided to the Chief Operating Decision Maker ("CODM") and included within each reported measure of a segment's profit or loss. The ASU also requires disclosure of the title and position of the individual identified as the CODM and an explanation of how the CODM uses the reported measures of a segment's profit or loss in assessing segment performance and deciding how to allocate resources. Additionally, ASU 2023-07 requires all segment profit or loss and assets disclosures to be provided on an annual and interim basis. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning one year later. Early adoption is permitted and the amendments must be applied retrospectively to all prior periods presented. The Company does not expect the adoption of this guidance to materially affect the consolidated financial statements, and the Company is currently evaluating the effect the guidance will have on its disclosures.

Investments

Investments	12 Months Ended
	Dec. 31, 2023
Investments [Abstract]
Investments	Investments Available-for-sale investments The following tables summarize the Company’s available-for-sale investments at December 31, 2023 and 2022: December 31, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Allowance for Credit Losses Estimated Fair Value (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 28,003 $ 57 $ (806) $ — $ 27,254 Obligations of states, municipalities and political subdivisions 191,080 212 (20,248) — 171,044 Corporate and other securities 1,437,468 5,532 (54,755) (552) 1,387,693 Asset-backed securities 641,700 2,833 (2,773) — 641,760 Residential mortgage-backed securities 463,904 1,732 (48,530) — 417,106 Commercial mortgage-backed securities 72,308 11 (5,416) (1) 66,902 Total fixed-maturity investments $ 2,834,463 $ 10,377 $ (132,528) $ (553) $ 2,711,759 December 31, 2022 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Allowance for Credit Losses Estimated Fair Value (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 17,934 $ — $ (1,193) $ — $ 16,741 Obligations of states, municipalities and political subdivisions 230,746 330 (26,444) — 204,632 Corporate and other securities 909,285 730 (76,757) (366) 832,892 Asset-backed securities 361,248 292 (8,534) — 353,006 Residential mortgage-backed securities 349,066 52 (55,156) — 293,962 Commercial mortgage-backed securities 65,353 — (6,486) — 58,867 Total fixed-maturity investments $ 1,933,632 $ 1,404 $ (174,570) $ (366) $ 1,760,100 Available-for-sale investments in a loss position The Company regularly reviews all its available-for-sale investments with unrealized losses to assess whether the decline in the fair value is deemed to be a credit loss. The Company considers a number of factors in completing its review of credit losses, including the extent to which a security's fair value has been below cost and the financial condition of an issuer. In addition to specific issuer information, the Company also evaluates the current market and interest rate environment. Generally, a change in a security’s value caused by a change in the market or interest rate environment does not constitute a credit loss. For fixed-maturity securities, the Company also considers whether it intends to sell the security or if it is more likely than not that it will be required to sell the security before recovery and the ability to recover all amounts outstanding when contractually due. When assessing whether it intends to sell a fixed-maturity security or if it is likely to be required to sell a fixed-maturity security before recovery of its amortized cost, the Company evaluates facts and circumstances including, but not limited to, decisions to reposition the investment portfolio, potential sales of investments to meet cash flow needs and potential sales of investments to capitalize on favorable pricing. For fixed-maturity securities where a decline in fair value is below the amortized cost basis and the Company intends to sell the security, or it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost, an impairment is recognized in net income based on the fair value of the security at the time of assessment. For fixed-maturity securities that the Company does not intend to sell or for which it is more likely than not that the Company would not be required to sell before recovery of its amortized cost, the Company compares the estimated present value of the cash flows expected to be collected to the amortized cost of the security. Inputs into the present value cash flow analysis include default rates and recoverability rates based on credit rating. The extent to which the estimated present value of the cash flows expected to be collected is less than the amortized cost of the security represents the credit-related portion of the impairment, which is recognized in net income through an allowance for credit losses. Any remaining decline in fair value represents the noncredit portion of the impairment, which is recognized in other comprehensive income. The Company reports investment income due and accrued separately from fixed-maturity securities, available for sale, and has elected not to measure an allowance for credit losses for investment income due and accrued. Investment income due and accrued is written off through earnings at the time the issuer of the bond defaults or is expected to default on payments. As of December 31, 2023, the Company's credit loss review resulted in an allowance for credit losses on 6 securities. The following table presents changes in the allowance for expected credit losses on available-for-sale securities: Years Ended December 31, 2023 2022 (in thousands) Beginning balance $ 366 $ — Increase to allowance from securities for which credit losses were not previously recorded 1 366 Reduction from securities sold during the period (12) — Net increase from securities that had an allowance at the beginning of the period 198 — Ending balance $ 553 $ 366 The following tables summarize gross unrealized losses and estimated fair value for available-for-sale investments by length of time that the securities have continuously been in an unrealized loss position: December 31, 2023 Less than 12 Months 12 Months or Longer Total Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ — $ — $ 15,484 $ (806) $ 15,484 $ (806) Obligations of states, municipalities and political subdivisions 20,886 (221) 121,911 (20,027) 142,797 (20,248) Corporate and other securities 246,355 (1,444) 651,525 (53,311) 897,880 (54,755) Asset-backed securities 142,287 (872) 217,401 (1,901) 359,688 (2,773) Residential mortgage-backed securities 26,158 (49) 268,891 (48,481) 295,049 (48,530) Commercial mortgage-backed securities 8,775 (55) 56,731 (5,361) 65,506 (5,416) Total fixed-maturity investments $ 444,461 $ (2,641) $ 1,331,943 $ (129,887) $ 1,776,404 $ (132,528) At December 31, 2023, in addition to the securities included in the allowance for credit losses, the Company held 967 fixed-maturity securities with a total estimated fair value of $1.8 billion and gross unrealized losses of $132.5 million. Of those securities, 758 were in a continuous unrealized loss position for greater than one year. As discussed above, the Company regularly reviews all fixed-maturity securities within its investment portfolio to determine whether a credit loss has occurred. Based on the Company's review as of December 31, 2023, except for securities previously discussed, the securities' in unrealized loss positions were caused by interest rate changes or other market factors and were not credit-specific issues, nor did the Company intend to sell these securities. At December 31, 2023, 83.3% of the Company’s fixed-maturity securities were rated "A-" or better and all of Company's fixed-maturity securities made expected coupon payments under the contractual terms of the securities. December 31, 2022 Less than 12 Months 12 Months or Longer Total Estimated Fair Value Gross Unrealized Holding Losses Estimated Fair Value Gross Unrealized Holding Losses Estimated Fair Value Gross Unrealized Holding Losses (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 10,538 $ (447) $ 6,204 $ (746) $ 16,742 $ (1,193) Obligations of states, municipalities and political subdivisions 141,460 (20,347) 17,314 (6,097) 158,774 (26,444) Corporate and other securities 583,619 (42,675) 156,148 (34,082) 739,767 (76,757) Asset-backed securities 216,487 (5,429) 97,703 (3,105) 314,190 (8,534) Residential mortgage-backed securities 98,909 (12,324) 194,773 (42,832) 293,682 (55,156) Commercial mortgage-backed securities 50,666 (4,732) 8,201 (1,754) 58,867 (6,486) Total fixed-maturity investments $ 1,101,679 $ (85,954) $ 480,343 $ (88,616) $ 1,582,022 $ (174,570) Contractual maturities of available-for-sale fixed-maturity securities The amortized cost and estimated fair value of available-for-sale fixed-maturity securities at December 31, 2023 are summarized, by contractual maturity, as follows: Amortized Estimated Cost Fair Value (in thousands) Due in one year or less $ 193,054 $ 191,792 Due after one year through five years 1,051,112 1,038,158 Due after five years through ten years 184,603 167,555 Due after ten years 227,782 188,486 Asset-backed securities 641,700 641,760 Residential mortgage-backed securities 463,904 417,106 Commercial mortgage-backed securities 72,308 66,902 Total fixed maturities $ 2,834,463 $ 2,711,759 Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties, and the lenders may have the right to put the securities back to the borrower. Real estate investments During the year ended December 31, 2022, the Company purchased a real estate investment property. Real estate investments consisted of the following at December 31, 2023 and 2022: December 31, 2023 2022 (in thousands) Building $ — $ 44,931 Land 14,791 17,946 Intangible in-place lease — 9,749 Site improvements — 2,686 Parking deck — 1,311 14,791 76,623 Accumulated depreciation — (236) Total real estate investments, net $ 14,791 $ 76,387 During the third quarter of 2023, the Company sold the parking deck, one of the office buildings and the related in-place leases of its real estate investment property for approximately $62.0 million in cash, net of seller’s costs. The Company recognized a gain on the sale of $4.3 million, which is included in net realized investment gains on the consolidated statement of income. The Company used the net sale proceeds to pay down a portion of its Credit Facility. Concurrent with the sale of the investment property, the Company refined its plans for the remainder of the property and determined the predominant use of the remaining office building would be for future office space expansion. Upon this determination, the Company reclassified the carrying value of the building to construction in progress within property and equipment. Net investment income The following table presents the components of net investment income: Year Ended December 31, 2023 2022 2021 (in thousands) Interest: Taxable bonds $ 92,227 $ 44,806 $ 25,654 Municipal bonds (tax exempt) 2,217 3,380 3,501 Cash equivalents and short-term investments 3,004 1,251 12 Dividends on equity securities 5,097 4,406 3,962 Real estate investment income 3,716 234 — Gross investment income 106,261 54,077 33,129 Investment expenses (3,926) (2,795) (2,081) Net investment income $ 102,335 $ 51,282 $ 31,048 Investment expenses included depreciation expense related to real estate investments of $0.5 million and $0.2 million for the years ended December 31, 2023 and 2022, respectively. There were no real estate investments at December 31, 2021. Realized investment gains and losses The following table presents realized investment gains and losses: Year Ended December 31, 2023 2022 2021 (in thousands) Fixed-maturity securities: Realized gains $ 1,852 $ 1,078 $ 2,944 Realized losses (2,374) (904) (3) Net realized (losses) gains from fixed-maturity securities (522) 174 2,941 Equity securities: Realized gains 7,678 1,363 97 Realized losses (5,329) (297) (210) Net realized gains (losses) from equity securities 2,349 1,066 (113) Realized losses from the sales of short-term investments (37) (49) — Realized gain on sale of real estate investments 4,250 — — Net realized investment gains $ 6,040 $ 1,191 $ 2,828 The net realized gains or losses on sales of equity securities represent the total gains or losses from the purchase dates of the equity securities. The change in unrealized gains (losses) in the consolidated statement of income consists of two components: (1) the reversal of the gain or loss recognized in previous periods on equity securities sold and (2) the change in unrealized gain or loss resulting from mark-to-market adjustments on equity securities still held. Change in net unrealized gains (losses) on fixed-maturity securities The change in net unrealized gains (losses) for fixed-maturity securities was $51.0 million, $(193.7) million, and $(29.4) million for the years ended December 31, 2023, 2022, and 2021, respectively. Insurance – statutory deposits The Company had invested assets with a carrying value of $5.8 million and $5.9 million on deposit with state regulatory authorities at December 31, 2023 and 2022, respectively. Payable for investments purchased The Company recorded a payable for investments purchased, not yet settled, of $12.3 million and $1.8 million at December 31, 2023 and 2022, respectively. The payable balance was included in the other liabilities line item of the consolidated balance sheet.

Fair value measurements

Fair value measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair value measurements	Fair value measurements Fair value is estimated for each class of financial instrument based on the framework established in the fair value accounting guidance. Fair value is defined as the price in the principal market that would be received for an asset or paid to transfer a liability to facilitate an orderly transaction between market participants on the measurement date. Market participants are assumed to be independent, knowledgeable, able and willing to transact an exchange and not acting under duress. Fair value hierarchy disclosures are based on the quality of inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). Adjustments to transaction prices or quoted market prices may be required in illiquid or disorderly markets in order to estimate fair value. The three levels of the fair value hierarchy are defined as follows: Level 1 - Inputs to the valuation methodology are quoted prices (unadjusted) for identical assets or liabilities traded in active markets. Level 2 - Inputs to the valuation methodology 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 and market-corroborated inputs. Level 3 - Inputs to the valuation methodology are unobservable for the asset or liability and are significant to the fair value measurement. Fair values of the Company's investment portfolio are estimated using unadjusted prices obtained by its investment accounting vendor from nationally recognized third-party pricing services, where available. Values for U.S. Treasuries, exchange traded funds and common stocks are generally based on Level 1 inputs which use quoted prices in active markets for identical assets. For other fixed-maturity securities and non-redeemable preferred stock, the pricing vendors use a pricing methodology involving the market approach, including pricing models which use prices and relevant market information regarding a particular security or securities with similar characteristics to establish a valuation. The estimates of fair value of these investments are included in the amounts disclosed as Level 2. For those investments where significant inputs are unobservable, the Company's investment accounting vendor obtains valuations from pricing vendors or brokers using the market approach and income approach valuation techniques and are disclosed as Level 3. Management performs several procedures to ascertain the reasonableness of investment values included in the consolidated financial statements at December 31, 2023 and 2022, including 1) obtaining and reviewing internal control reports from the Company's investment accounting vendor that assess fair values from third party pricing services, 2) discussing with the Company's investment accounting vendor its process for reviewing and validating pricing obtained from third party pricing services and 3) reviewing the security pricing received from the Company's investment accounting vendor and monitoring changes in unrealized gains and losses at the individual security level. The Company has evaluated the various types of securities in its investment portfolio to determine an appropriate fair value hierarchy level based upon trading activity and the observability of market inputs. The following tables present the balances of assets measured at fair value on a recurring basis as of December 31, 2023 and 2022, by level within the fair value hierarchy: December 31, 2023 Level 1 Level 2 Level 3 Total (in thousands) Assets Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 22,235 $ 5,019 $ — $ 27,254 Obligations of states, municipalities and political subdivisions — 171,044 — 171,044 Corporate and other securities — 1,387,693 — 1,387,693 Asset-backed securities — 641,760 — 641,760 Residential mortgage-backed securities — 417,106 — 417,106 Commercial mortgage-backed securities — 66,902 — 66,902 Total fixed maturities 22,235 2,689,524 — 2,711,759 Equity securities: Exchange traded funds 106,300 — — 106,300 Non-redeemable preferred stock — 33,173 — 33,173 Common stocks 95,340 — — 95,340 Total equity securities 201,640 33,173 — 234,813 Short-term investments 1,862 3,727 — 5,589 Total $ 225,737 $ 2,726,424 $ — $ 2,952,161 December 31, 2022 Level 1 Level 2 Level 3 Total (in thousands) Assets Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 16,741 $ — $ — $ 16,741 Obligations of states, municipalities and political subdivisions — 204,632 — 204,632 Corporate and other securities — 832,892 — 832,892 Asset-backed securities — 353,006 — 353,006 Residential mortgage-backed securities — 293,962 — 293,962 Commercial mortgage-backed securities — 58,867 — 58,867 Total fixed maturities 16,741 1,743,359 — 1,760,100 Equity securities: Exchange traded funds 104,202 — — 104,202 Non-redeemable preferred stock — 38,162 — 38,162 Common stocks 10,107 — — 10,107 Total equity securities 114,309 38,162 — 152,471 Short-term investments 31,366 9,971 — 41,337 Total $ 162,416 $ 1,791,492 $ — $ 1,953,908 There were no assets or liabilities measured at fair value on a nonrecurring basis as of December 31, 2023 or 2022. The carrying amount of the Company's fixed-rate senior notes was $175.0 million and $125.0 million, less debt issuance cost, and the corresponding estimated fair value was $171.6 million and $117.2 million at December 31, 2023 and 2022, respectively. The fair value measurement was determined using a discounted cash flow analysis that factors in current market yields for comparable borrowing arrangements under the Company's credit profile. Since this methodology is based upon market yields for comparable arrangements, the measurement is categorized as Level 2. The estimated fair value of outstanding borrowings under the Company's revolving Credit Facility approximated its carrying value at December 31, 2023 and 2022. See Note 11 for further information regarding the Company's debt arrangements.

Deferred policy acquisition cos

Deferred policy acquisition costs	12 Months Ended
	Dec. 31, 2023
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred policy acquisition costs	Deferred policy acquisition costs The following table presents the amounts of policy acquisition costs deferred and amortized for the years ended: Year Ended December 31, 2023 2022 2021 (in thousands) Balance, beginning of year $ 61,594 $ 41,968 $ 31,912 Policy acquisition costs deferred: Direct commissions 227,755 160,523 111,463 Ceding commissions (88,449) (48,022) (28,965) Other underwriting and policy acquisition costs 10,982 8,155 6,191 Policy acquisition costs deferred 150,288 120,656 88,689 Amortization of net policy acquisition costs (123,487) (101,030) (78,633) Balance, end of year $ 88,395 $ 61,594 $ 41,968 Amortization of net policy acquisition costs is included in underwriting, acquisition and insurance expense in the accompanying consolidated statements of income and comprehensive income.

Underwriting, acquisition and i

Underwriting, acquisition and insurance expenses	12 Months Ended
	Dec. 31, 2023
Underwriting, Acquisition and Insurance Expenses [Abstract]
Underwriting, acquisition and insurance expenses	Underwriting, acquisition and insurance expenses Underwriting, acquisition and insurance expenses consist of the following: Year Ended December 31, 2023 2022 2021 (in thousands) Underwriting, acquisition and insurance expenses incurred: Direct commissions $ 198,715 $ 138,451 $ 98,847 Ceding commissions (84,998) (44,695) (25,702) Other underwriting expenses 115,253 86,566 65,448 Total $ 228,970 $ 180,322 $ 138,593 Other underwriting expenses within underwriting, acquisition and insurance expenses included salaries, employee benefits and bonus expense of $85.7 million, $64.8 million and $48.9 million, for the years ended December 31, 2023, 2022 and 2021, respectively.

Income taxes

Income taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income taxes	Income taxes The Company’s subsidiaries file a consolidated U.S. federal income tax return. Under a tax sharing agreement, Kinsale collects from or refunds to its subsidiaries the amount of taxes determined as if Kinsale and the subsidiaries filed separate returns. The Company is no longer subject to income tax examination by tax authorities for the years ended before January 1, 2020. Income tax expense includes the following components for the years ending December 31, 2023, 2022 and 2021: Year Ended December 31, 2023 2022 2021 (in thousands) Current federal income tax expense $ 85,353 $ 50,641 $ 36,718 Deferred federal income tax (benefit) expense (9,429) (14,191) (576) Income tax expense $ 75,924 $ 36,450 $ 36,142 The Company paid $84.6 million, $43.1 million and $40.6 million in federal income taxes during the years ended December 31, 2023, 2022 and 2021, respectively. Current income taxes payable were $3.2 million and $2.5 million at December 31, 2023 and 2022, respectively, and included in other liabilities in the accompanying consolidated balance sheets. The prevailing federal income tax rate was 21% in December 31, 2023, 2022 and 2021. The Company’s effective income tax rate on income before income taxes differs from the prevailing federal income tax rate and is summarized as follows: Year ended December 31, 2023 2022 2021 (in thousands) Income tax expense at federal income tax rate $ 80,644 $ 41,068 $ 39,648 Stock options exercised (3,676) (3,240) (2,148) Restricted stock award vesting (1,256) (1,048) (677) Tax-exempt investment income (347) (527) (546) Other 559 197 (135) Total $ 75,924 $ 36,450 $ 36,142 The significant components of the net deferred tax asset are summarized as follows: December 31, 2023 2022 (in thousands) Deferred tax assets: Unrealized losses on fixed-maturity securities $ 25,655 $ 36,370 Unpaid losses and loss adjustment expenses 27,422 20,256 Unearned premiums 27,251 19,183 State operating loss carryforwards 6,012 5,351 Stock compensation 2,155 1,521 Allowance for credit losses 2,810 1,694 Other 2,394 474 Deferred tax assets before allowance 93,699 84,849 Less: valuation allowance (6,182) (5,188) Total deferred tax assets 87,517 79,661 Deferred tax liabilities: Unrealized gains on equity securities 8,667 5,459 Deferred policy acquisition costs, net of ceding commissions 18,563 12,935 Property and equipment 3,005 2,670 Other 1,583 1,614 Total deferred tax liabilities 31,818 22,678 Net deferred tax asset $ 55,699 $ 56,983 At December 31, 2023 and 2022, the Company had state net operating losses ("NOLs") of $126.8 million and $112.9 million, respectively. The state NOLs are available to offset future taxable income or reduce taxes payable and begin expiring in 2029. Management evaluates the need for a valuation allowance related to its deferred tax assets. At December 31, 2023 and 2022, the Company recorded a tax valuation allowance equal to the state NOLs and the deferred tax assets, net of existing deferred tax liabilities that were expected to reverse in future periods, related to certain state jurisdictions. No other valuation allowances were established against the Company’s deferred tax assets at December 31, 2023 and 2022, as the Company believes that it is more likely than not that the remaining deferred tax assets will be realized given the carry back availability, reversal of existing temporary differences and future taxable income. With respect to deferred tax assets associated with unrealized losses on fixed-maturity securities, management has the ability and intent to execute a tax planning strategy to hold those securities to recovery or maturity to the extent not matched with realized capital gains or available carry back to ensure recognition of the deferred tax asset. After consideration of all available evidence, we concluded that it is more likely than not that these deferred tax assets will be realized. The Company did not have any material uncertain tax positions in 2023 or 2022. Management is not aware of any events that would give rise to any material uncertain tax positions.

Reserves for unpaid losses and

Reserves for unpaid losses and loss adjustment expenses	12 Months Ended
	Dec. 31, 2023
Liability for Claims and Claims Adjustment Expense [Abstract]
Reserves for unpaid losses and loss adjustment expenses	Reserves for unpaid losses and loss adjustment expenses The reserves for unpaid losses and loss adjustment expenses represent the Company's estimated ultimate cost of all unreported and reported but unpaid insured claims and the cost to adjust these claims. Reserves are estimated using individual case-basis valuations of reported claims and statistical analyses. Case reserves are established for individual claims that have been reported to the Company, typically by the Company's insureds or their brokers. Based on the information provided, case reserves are established by estimating the ultimate losses from the claim, including defense costs associated with the ultimate settlement of the claim. Incurred-but-not-reported ("IBNR") reserves are determined using actuarial methods to estimate losses that have occurred but have not yet been reported to the Company. The incurred Bornhuetter-Ferguson actuarial method ("BF method") is used to arrive at the Company's loss reserve estimates for each line of business. This method estimates the reserves based on the initial expected loss ratio and expected reporting patterns for losses. Because the Company has a limited number of years of loss experience compared to the period over which losses are expected to be reported, the Company uses industry and peer-group data, in addition to its own data, as a basis for selecting its expected reporting patterns. As part of the reserving process, the Company reviews historical data and considers the effect of various factors on claims development patterns including polices written on a "claims made" versus "occurrence" basis. Policies written on a claims made basis provide coverage to the insured only for losses incurred during the coverage period, and only if the claim was reported during a specified reporting period. Policies written on an occurrence basis provide coverage to the insured for liabilities arising from events occurring during the term of the policy, regardless of when a claim is actually made. Accordingly, claims related to policies written on an occurrence basis may arise many years after a policy has lapsed. Property losses, while written on an occurrence basis, are generally reported within a short time from the date of loss, and in most instances, property claims are settled and paid within a relatively short period of time. The following table presents a reconciliation of consolidated beginning and ending reserves for unpaid losses and loss adjustment expenses: December 31, 2023 2022 2021 (in thousands) Gross reserves for unpaid losses and loss adjustment expenses, beginning of year $ 1,238,402 $ 881,344 $ 636,013 Less: reinsurance recoverable on unpaid losses 177,039 117,561 83,730 Net reserves for unpaid losses and loss adjustment expenses, beginning of year 1,061,363 763,783 552,283 Incurred losses and loss adjustment expenses: Current year 635,993 493,800 356,401 Prior years (35,774) (35,887) (31,986) Total net losses and loss adjustment expenses incurred 600,219 457,913 324,415 Payments: Current year 38,565 49,205 23,765 Prior years 171,499 111,128 89,150 Total payments 210,064 160,333 112,915 Net reserves for unpaid losses and loss adjustment expenses, end of year 1,451,518 1,061,363 763,783 Reinsurance recoverable on unpaid losses, net of allowance 241,357 177,039 117,561 Gross reserves for unpaid losses and loss adjustment expenses, end of year $ 1,692,875 $ 1,238,402 $ 881,344 During the year ended December 31, 2023, prior accident years developed favorably by $35.8 million, of which $49.0 million was attributable to the 2021 and 2022 accident years due to lower emergence of reported losses than expected across most lines of business. This favorable development was offset in part by adverse development largely from the 2017 through 2019 accident years due to long-tailed property damage claims within the construction-related primary casualty business that are more exposed to the increase in inflation. During the year ended December 31, 2022, prior accident years developed favorably by $35.9 million, of which $41.8 million was attributable to the 2020 and 2021 accident years due to lower emergence of reported losses than expected across most lines of business. This favorable development was offset in part by adverse development largely from the 2016 and 2018 accident years due to routine variability in reported losses and modest adjustments in actuarial assumptions. Current accident year incurred losses and loss adjustment expenses for the year ended December 31, 2022 included $26.6 million of catastrophe losses primarily related to Hurricane Ian. During the year ended December 31, 2021, prior accident years developed favorably by $32.0 million, of which $33.7 million was attributable to the 2020 accident year and was related to a lower-than-expected levels of reported losses. Although the Company did not have any significant direct COVID-19 loss exposure, the related disruption in the court system and the general economy created additional uncertainty in estimating loss reserves in 2020. As a result, accident year 2020 actuarial assumptions were adjusted in 2020 to increase IBNR to account for this additional uncertainty. In 2021, the Company's outlook was more favorable than in the prior year and, based on observed trends, the Company reevaluated and adjusted certain assumptions for accident year 2020 to reflect the favorable experience. In addition, $3.8 million of favorable development was attributable to accident year 2019 due to reported losses emerging at lower levels than expected. This favorable development was offset in part by adverse development, mostly attributable to the 2016 and 2018 accident years due to modest adjustments in actuarial assumptions. Current accident year incurred losses and loss adjustment expenses for the year ended December 31, 2021 included $8.6 million of catastrophe losses primarily related to Hurricane Ida and winter storms Uri and Viola in Texas. Incurred and Paid Claims Development The following is information about incurred and paid claims development as of December 31, 2023, net of reinsurance, as well as cumulative claim frequency and the total of IBNR liabilities plus expected development on reported claims included within the net incurred claims amounts. The development and claims duration tables below exclude commuted multi-line quota-share reinsurance treaty ("MLQS") contracts, which would distort development patterns related to those transactions. Cumulative number of reported claims is reported on a per claim basis. The information about incurred and paid claims development for the years ended December 31, 2014 to December 31, 2022, is presented as unaudited supplementary information. Property Incurred Claims and Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, As of December 31, 2023 Accident Year 2019 2020 2021 2022 2023 Total of IBNR Liabilities Plus Expected Development on Reported Claims Cumulative Number of Reported Claims ($ in thousands) 2019 $ 14,914 $ 13,909 $ 15,572 $ 16,748 $ 15,357 $ — 643 2020 40,612 37,939 36,807 37,078 214 2,309 2021 36,531 33,518 29,750 1,403 1,144 2022 67,127 53,676 4,744 2,330 2023 75,517 47,874 902 Total $ 211,378 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Accident Year 2019 2020 2021 2022 2023 ($ in thousands) 2019 $ 9,852 $ 12,581 $ 13,996 $ 14,511 $ 15,223 2020 19,897 30,321 31,765 35,023 2021 14,268 21,257 27,324 2022 33,004 46,965 2023 20,267 Total 144,802 All outstanding liabilities before 2019, net of reinsurance 3 Liabilities for claims and claim adjustment expenses, net of reinsurance $ 66,579 Historical Claims Duration The following is supplementary information about average historical claims duration as of December 31, 2023: Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Unaudited) Years 1 2 3 4 5 Property 50.8 % 23.8 % 11.2 % 6.1 % 4.6 % Casualty - Claims Made Incurred Claims and Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, As of December 31, 2023 Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 Total of IBNR Liabilities Plus Expected Development on Reported Claims Cumulative Number of Reported Claims ($ in thousands) 2014 $ 18,847 $ 14,289 $ 11,748 $ 11,217 $ 10,948 $ 10,988 $ 10,620 $ 10,266 $ 9,880 $ 9,868 $ 177 273 2015 18,883 16,777 14,896 13,583 13,942 13,548 13,414 13,066 12,759 93 259 2016 19,170 14,693 14,675 14,322 13,583 13,602 13,228 12,707 16 311 2017 18,116 17,097 16,120 15,794 14,989 13,698 13,471 661 372 2018 22,429 20,234 18,612 17,057 14,411 14,272 1,346 465 2019 34,693 29,056 26,426 24,489 21,788 4,227 562 2020 55,630 44,641 38,287 33,667 13,458 784 2021 84,018 66,191 52,935 36,436 1,077 2022 101,064 81,394 59,239 1,205 2023 115,858 98,185 1,336 Total $ 368,719 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 ($ in thousands) 2014 $ 435 $ 1,865 $ 5,039 $ 6,385 $ 8,290 $ 9,415 $ 9,491 $ 9,628 $ 9,638 $ 9,691 2015 217 4,496 7,563 9,238 11,372 11,522 12,142 12,463 12,474 2016 1,158 3,015 6,907 9,839 11,381 12,105 12,299 12,691 2017 340 4,897 8,252 10,484 11,357 12,235 12,335 2018 507 5,030 8,931 10,330 11,205 12,623 2019 2,487 6,005 10,123 14,476 15,406 2020 1,002 7,446 12,551 18,589 2021 1,146 8,437 12,895 2022 3,052 12,381 2023 4,830 Total 123,915 All outstanding liabilities before 2014, net of reinsurance 76 Liabilities for claims and claim adjustment expenses, net of reinsurance $ 244,880 Casualty - Occurrence Incurred Claims and Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, As of December 31, 2023 Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 Total of IBNR Liabilities Plus Expected Development on Reported Claims Cumulative Number of Reported Claims ($ in thousands) 2014 $ 47,805 $ 40,668 $ 38,049 $ 36,678 $ 39,313 $ 41,859 $ 42,434 $ 41,367 $ 41,677 $ 41,820 $ 2,546 1,261 2015 59,717 51,739 49,122 52,100 54,697 54,090 54,090 54,637 55,259 4,062 1,913 2016 61,440 55,680 53,549 55,534 57,401 60,861 64,612 65,323 6,331 1,640 2017 71,126 67,151 68,985 70,641 71,117 69,911 76,715 10,589 2,141 2018 86,157 78,331 78,386 83,952 93,215 97,005 17,691 2,380 2019 112,266 109,994 108,138 107,480 115,681 35,995 2,370 2020 154,619 136,212 131,082 135,045 86,636 2,681 2021 200,598 190,879 193,722 144,372 2,827 2022 272,692 271,399 227,940 3,064 2023 372,245 358,062 2,195 Total $ 1,424,214 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 ($ in thousands) 2014 $ 698 $ 3,081 $ 8,489 $ 17,576 $ 23,771 $ 31,026 $ 34,338 $ 35,807 $ 37,375 $ 38,169 2015 941 3,161 12,685 28,385 37,690 41,724 44,161 47,106 49,147 2016 1,099 6,015 17,225 28,924 34,437 43,311 51,533 55,595 2017 1,581 9,352 22,407 37,736 46,025 52,069 61,108 2018 2,638 10,995 22,860 35,138 54,441 72,174 2019 3,944 16,687 30,518 46,478 69,384 2020 2,400 8,673 17,805 32,606 2021 3,205 12,944 31,494 2022 4,658 23,084 2023 4,329 Total 437,090 All outstanding liabilities before 2014, net of reinsurance 2,868 Liabilities for claims and claim adjustment expenses, net of reinsurance $ 989,992 Historical Claims Duration The following is supplementary information about average historical claims duration as of December 31, 2023: Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Unaudited) Years 1 2 3 4 5 6 7 8 9 10 Casualty - claims made 4.6 % 21.0 % 22.7 % 16.3 % 10.8 % 6.9 % 2.0 % 2.3 % 0.1 % 0.5 % Casualty - occurrence 2.0 % 7.1 % 13.1 % 17.9 % 15.1 % 12.9 % 9.2 % 5.0 % 3.7 % 1.9 % Reconciliation of Incurred and Paid Claims Development to the Liability for Unpaid Claims and Claim Adjustment Expenses The reconciliation of the net incurred and paid claims development tables to the liability for unpaid claims and claim adjustment expenses in the consolidated statement of financial position is as follows: (in thousands) December 31, 2023 Net outstanding liabilities Property $ 66,579 Casualty - claims made 244,880 Casualty - occurrence 989,992 Liabilities for unpaid claims and claim adjustment expenses, net of reinsurance 1,301,451 Reinsurance recoverable on unpaid claims Property 60,888 Casualty - claims made 21,393 Casualty - occurrence 159,820 Allowance for credit losses (744) Total reinsurance recoverable on unpaid claims 241,357 Unallocated claims adjustment expenses 149,323 Allowance for credit losses 744 Gross liability for unpaid claims and claim adjustment expense $ 1,692,875

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2023
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance The Company purchases reinsurance from other insurance companies ("reinsurers") in order to limit its exposure to large losses and enable it to underwrite policies with sufficient limits to meet policyholder needs. In a reinsurance transaction, an insurance company transfers, or cedes, part or all of its exposure to the reinsurer that receives a portion of the premium. The ceding of insurance does not legally discharge the Company from its primary liability for the full amount of the policy coverage, and therefore the Company will be required to pay the loss and bear collection risk if the reinsurer fails to meet its obligations under the reinsurance agreement. The following table summarizes the effect of reinsurance on premiums written and earned: Year Ended December 31, 2023 2022 2021 (in thousands) Written: Direct $ 1,568,815 $ 1,102,092 $ 764,373 Ceded (304,185) (165,282) (104,164) Net written $ 1,264,630 $ 936,810 $ 660,209 Earned: Direct $ 1,367,141 $ 950,145 $ 677,630 Ceded (294,604) (156,026) (94,751) Net earned $ 1,072,537 $ 794,119 $ 582,879 Incurred losses and loss adjustment expenses were net of reinsurance recoverables (ceded incurred losses and loss adjustment expenses) of $115.9 million, $117.9 million and $49.7 million for the years ended December 31, 2023, 2022 and 2021, respectively. Reinsurance balances The following table presents reinsurance recoverables on paid and unpaid losses as of December 31, 2023 and 2022: December 31, 2023 December 31, 2022 (in thousands) Reinsurance recoverables on paid losses $ 6,479 $ 43,415 Reinsurance recoverables on unpaid losses 241,357 177,039 Reinsurance recoverables $ 247,836 $ 220,454 Credit risk exists with reinsurance ceded to the extent that any reinsurer is unable to meet the obligations assumed under the reinsurance agreements. Allowances are established for amounts deemed uncollectible. The Company evaluates the financial condition of its reinsurers and monitors concentration of credit risk arising from its exposure to individual reinsurers. All reinsurance recoverables are from companies with A.M. Best ratings of "A-" (Excellent) or better. To further reduce credit exposure to reinsurance recoverable balances, the Company has received letters of credit from certain reinsurers that are not authorized as reinsurers under U.S. state insurance regulations. The Company recorded an allowance for credit losses of $0.7 million and $0.5 million related to its reinsurance balances at December 31, 2023 and 2022, respectively; however, the deterioration in the credit quality of existing reinsurers or disputes over reinsurance agreements could result in future charges. At December 31, 2023, reinsurance recoverables on paid and unpaid losses from the Company’s five largest reinsurers were $64.1 million, $31.0 million, $27.3 million, $23.4 million and $17.7 million, representing 66.0% of the total balance. At December 31, 2023, unearned premiums ceded to five reinsurers were $11.9 million, $6.1 million, $5.5 million, $5.4 million, and $4.9 million representing 64.4% of the total balance.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2023
Equity, Attributable to Parent [Abstract]
Stockholders' equity	Stockholders’ equity Capital Stock The Company’s authorized capital stock consists of 400,000,000 shares of common stock, par value $0.01 per share, and 100,000,000 shares of preferred stock, par value $0.01 per share. There were no shares of preferred stock issued or outstanding at December 31, 2023 or 2022. Public Offerings In November 2022, the Company completed an underwritten public offering and sold and issued 155,000 shares of its common stock at a price of $308.30 per share, to the underwriter. The Company received net proceeds from the offering of $47.5 million. Equity-based Compensation On July 27, 2016, the Kinsale Capital Group, Inc. 2016 Omnibus Incentive Plan (the "2016 Incentive Plan") became effective. The 2016 Incentive Plan, which is administered by the Compensation, Nominating and Corporate Governance Committee of the Company's Board of Directors, provides for grants of stock options, restricted stock, restricted stock units and other stock-based awards to officers, employees, directors, independent contractors and consultants. The number of shares of common stock available for issuance under the 2016 Incentive Plan may not exceed 2,073,832. The Company recognized total equity-based compensation expense of $9.4 million, $6.7 million and $4.8 million for the years ended December 31, 2023, 2022 and 2021, respectively. Stock Options On July 27, 2016, the Board of Directors approved, and the Company granted, 1,036,916 stock options with an exercise price equal to the initial public offering price of $16.00 per share. The options have a maximum contractual term of 10 years and vested in 4 equal annual installments following the date of the grant. The weighted average grant date fair value of options granted during 2016 was $2.71 per share. The value of the options granted was estimated at the date of grant using the Black-Scholes pricing model. A summary of option activity as of December 31, 2023 and changes during the year then ended is presented below: Number of Shares Weighted-average exercise price Weighted-average remaining years of contractual life Aggregate intrinsic value (in thousands) Outstanding at December 31, 2022 256,357 $ 16.00 Granted — — Forfeited — — Exercised (54,797) 16.00 Outstanding at December 31, 2023 201,560 $ 16.00 2.6 $ 64,280 Exercisable at December 31, 2023 201,560 $ 16.00 2.6 $ 64,280 The total intrinsic value of options exercised was $17.7 million during the year ended December 31, 2023 and $15.6 million during the year ended December 31, 2022. Restricted Stock Awards During 2023, the Board of Directors approved, and the Company granted, restricted stock awards under the 2016 Incentive Plan. The restricted stock awards were valued on the date of grant and will vest over a period of 1 to 4 years corresponding to the anniversary date of the grants. The fair value of restricted stock awards was determined based on the closing trading price of the Company’s common stock on the grant date or, if no common stock was traded on the grant date, the last preceding date for which there was a sale of common stock. Except for restrictions placed on the transferability of restricted stock, holders of unvested restricted stock have full stockholder’s rights, including voting rights and the right to receive cash dividends. Unvested restricted stock awards and accrued dividends, if any, are forfeited upon the termination of service to or employment with the Company. A summary of restricted stock activity under the equity compensation plans for the year ended is as follows: December 31, 2023 Number of Shares Weighted Average Grant Date Fair Value per Share Nonvested outstanding at the beginning of the period 98,621 $ 182.37 Granted 51,176 $ 313.35 Vested (40,951) $ 163.98 Forfeited (1,024) $ 252.44 Nonvested outstanding at the end of the period 107,822 $ 250.86 Employees surrender restricted stock awards to pay for withholding tax obligations resulting from any vesting of those awards. During the year ended December 31, 2023, restricted stock awards withheld for taxes in connection with the vesting of those awards totaled 13,556. The per share weighted average grant-date fair value of the Company's restricted stock awards granted during the years ended December 31, 2023, 2022 and 2021 was $313.35, $211.86 and $185.00, respectively. The fair value of restricted stock awards that vested during the year ended December 31, 2023, 2022 and 2021 was $12.8 million, $10.0 million and $6.8 million, respectively. As of December 31, 2023, the Company had $19.2 million of total unrecognized stock-based compensation expense expected to be charged to earnings over a weighted-average period of 2.3 years. Subsequent Events The Board of Directors granted 3,576 restricted stock awards on January 1, 2024 under the 2016 Incentive Plan to the Company’s non-employee directors. The restricted stock awards had a fair value on the date of grant of $334.91 per share and will vest on the first anniversary date of the grant. On February 12, 2024, the Company’s Board of Directors declared a cash dividend of $0.15 per share of common stock. This dividend is payable on March 13, 2024 to all stockholders of record on February 27, 2024.

Earnings per share

Earnings per share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Earnings per share	Earnings per share The following table represents a reconciliation of the numerator and denominator of the basic and diluted earnings per share computations contained in the consolidated financial statements: Year ended December 31, 2023 2022 2021 (in thousands, except per share data) Net income $ 308,093 $ 159,114 $ 152,659 Weighted average common shares outstanding - basic 23,045 22,815 22,693 Dilutive effect of shares issued under stock compensation arrangements: Stock options 214 269 324 Restricted stock awards 48 41 45 Total dilutive effect of shares issued under stock compensation arrangements 262 310 369 Weighted average common shares outstanding - diluted 23,307 23,125 23,062 Earnings per common share: Basic $ 13.37 $ 6.97 $ 6.73 Diluted $ 13.22 $ 6.88 $ 6.62 There were 1 thousand, zero and 30 thousand anti-dilutive stock awards for the years ended December 31, 2023, 2022 and 2021, respectively.

Debt

Debt	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Credit Agreement	Debt Note Purchase and Private Shelf Agreement On July 22, 2022, the Company entered into a Note Purchase and Private Shelf Agreement (the "Note Purchase Agreement") with PGIM, Inc. ("Prudential") and the purchasers of the Series A Notes (as defined below), named in the Purchaser Schedule attached thereto (collectively, the "Note Purchasers"). Pursuant to the Note Purchase Agreement, on July 22, 2022, the Company issued $125.0 million aggregate principal amount of 5.15% Series A Senior Notes Due July 22, 2034 (collectively, the "Series A Notes") to the Note Purchasers. The Note Purchase Agreement also provides for the issuance of additional shelf notes issued thereunder (the "Shelf Notes" and, together with the Series A Notes, the "Notes") not to exceed $150.0 million of Notes outstanding thereunder. On September 18, 2023, the Company entered into a First Amendment to the Note Purchase Agreement and increased the additional Shelf Notes limit to $200.0 million. Pursuant to the First Amendment to the Note Purchase Agreement, on September 18, 2023, the Company issued a $50.0 million aggregate principal amount 6.21% Series B Senior Note due July 22, 2034 to the note purchaser. The Series A and B Notes are senior unsecured obligations of the Company and rank pari passu with the Company’s Amended and Restated Credit Agreement. The Series A Notes bear interest at 5.15% per annum and mature on July 22, 2034, unless paid earlier by the Company. Should the Company elect to prepay the Series A Notes, such aggregate prepayment will include the applicable make-whole amount(s), as defined within the applicable Note Purchase Agreement. Principal payments are required annually beginning on July 22, 2030 in equal installments of $25.0 million through July 22, 2034. The Series B Note bears interest at 6.21% per annum and matures on July 22, 2034, unless paid earlier by the Company. Should the Company elect to prepay the Series B Note, such aggregate prepayment will include the applicable make-whole amount(s), as defined within the applicable Note Purchase Agreement. Principal payments are required annually beginning on July 22, 2030 in equal installments of $10.0 million through July 22, 2034. Credit Agreement On May 28, 2019, the Company entered into a Credit Agreement (the "Credit Agreement") that provided the Company with a $50.0 million senior unsecured revolving credit facility (the "Credit Facility") and an uncommitted accordion feature that permits the Company to increase the commitments by an additional $30.0 million. On July 22, 2022, the Company entered into an Amended and Restated Credit Agreement, with JPMorgan Chase Bank, N.A., as administrative agent and as issuing bank, Truist Bank, as syndication agent, and the lenders party thereto (collectively, the "Lenders"). The Amended and Restated Credit Agreement extended the maturity date to July 22, 2027, and increased the aggregate commitment to $100.0 million, with the option to increase the aggregate commitment by $30.0 million, subject to the Company obtaining commitments from existing or new lenders and satisfying other conditions specified in the Amended and Restated Credit Agreement. The Company is required to pay a Commitment Fee Rate (as defined therein) of 0.25% on the average daily amount of the Available Revolving Commitment (as defined therein). Borrowings under the Amended and Restated Credit Agreement may be used for general corporate purposes (which may include, without limitation, to fund future growth, to finance working capital needs, to fund capital expenditures, and to refinance, redeem or repay indebtedness). In September 2023, the Company used proceeds from the sale of its real estate investment property to pay down $62.0 million from the Credit Facility. The loans under the Amended and Restated Credit Agreement bear interest, at the Company's option, at a rate equal to the Adjusted Term SOFR Rate (as defined therein) plus 1.625% or the Alternate Base Rate (as defined therein) plus 0.625%. For the year ended December 31, 2023, the annual weighted-average interest rate of borrowings under the Credit Facility was 6.84%. The following table presents the Company's outstanding debt as of December 31, 2023 and December 31, 2022: Issuance Maturities December 31, 2023 December 31, 2022 (in thousands) Credit Facility Various 7/22/2027 $ 11,000 $ 73,000 5.15% Series A Notes 7/22/2022 7/22/2034 125,000 125,000 6.21% Series B Note 9/18/2023 7/22/2034 50,000 — Less: Unamortized debt issuance costs (2,154) (2,253) Total debt $ 183,846 $ 195,747 Interest paid under both agreements totaled $10.5 million, $2.4 million and $0.9 million for the years ended December 31, 2023, 2022 and 2021, respectively.

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Contingencies arise in the normal conduct of the Company’s operations and are not expected to have a material effect on the Company’s financial condition or results of operations. However, adverse outcomes are possible and could negatively affect the Company’s financial condition and results of operations. In June 2019, Marie Hughes, as authorized administrator for the estate of George Hughes, filed a wrongful death claim against Venetian Hills Apartments, LLC ("Venetian Hills") in DeKalb County in Georgia state court. On December 20, 2023, the jury awarded a verdict to the plaintiff of $140 million. Venetian Hills was a policyholder of a $1 million general liability policy issued by Kinsale Insurance. The Company believes exclusions in the policy apply to the claim and intends to defend any action related to this proceeding vigorously. The Company expects to appeal the verdict at the conclusion of post trial motions and does not expect a resolution as to the Company’s liability, if any, with respect to this matter in the foreseeable future, and potentially for multiple years. The Company does not believe this legal proceeding will have a material adverse effect on its results of operations or business. The Company believes adequate provision has been made in its consolidated financial statements and its existing reserves account for liabilities to the Company relating to claims such as this legal proceeding.
Legal Matters and Contingencies	In June 2019, Marie Hughes, as authorized administrator for the estate of George Hughes, filed a wrongful death claim against Venetian Hills Apartments, LLC ("Venetian Hills") in DeKalb County in Georgia state court. On December 20, 2023, the jury awarded a verdict to the plaintiff of $140 million. Venetian Hills was a policyholder of a $1 million general liability policy issued by Kinsale Insurance. The Company believes exclusions in the policy apply to the claim and intends to defend any action related to this proceeding vigorously. The Company expects to appeal the verdict at the conclusion of post trial motions and does not expect a resolution as to the Company’s liability, if any, with respect to this matter in the foreseeable future, and potentially for multiple years. The Company does not believe this legal proceeding will have a material adverse effect on its results of operations or business. The Company believes adequate provision has been made in its consolidated financial statements and its existing reserves account for liabilities to the Company relating to claims such as this legal proceeding.

Employee benefit plan

Employee benefit plan	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Employee benefit plan	Employee benefit plan The Company has established a defined contribution employee retirement plan ("Plan") in accordance with Section 401(k) of the Internal Revenue Code. Expenses related to the Plan were $3.8 million, $3.1 million and $2.2 million in 2023, 2022 and 2021, respectively.

Other comprehensive income (los

Other comprehensive income (loss)	12 Months Ended
	Dec. 31, 2023
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other comprehensive income (loss)	Other comprehensive income (loss) The following table summarizes the components of other comprehensive income (loss): Year Ending December 31, 2023 2022 2021 (in thousands) Unrealized gains (losses) on fixed-maturity securities arising during the period, before income taxes: $ 49,384 $ (193,970) $ (26,792) Income tax (expense) benefit (10,371) 40,734 5,626 Unrealized gains (losses) arising during the period, net of income taxes 39,013 (153,236) (21,166) Less reclassification adjustment: Net realized investment (losses) gains on available-for-sale investments (1,443) 121 2,644 Income tax benefit (expense) 303 (25) (555) Reclassification adjustment included in net income (1,140) 96 2,089 Change in allowance for credit losses on investments, before income taxes (187) (366) — Income tax benefit 39 77 — Reclassification adjustment included in net income (148) (289) — Other comprehensive income (loss) $ 40,301 $ (153,043) $ (23,255) The sale of or credit loss on an available-for-sale security results in amounts being reclassified from accumulated other comprehensive income to realized gains or losses in current period earnings. The related tax effect of the reclassification adjustment is recorded in income tax expense in current period earnings. See Note 2 for additional information.

Underwriting information

Underwriting information	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Underwriting information	Underwriting information The Company has one reportable segment, the Excess and Surplus Lines Insurance segment, which primarily offers commercial excess and surplus lines liability and property insurance products through its underwriting divisions. Gross written premiums by underwriting division are presented below: Year Ended December 31, 2023 2022 2021 (in thousands) Commercial: Commercial Property $ 411,956 $ 181,505 $ 72,392 Excess Casualty 194,049 147,485 108,487 Small Business Casualty 174,080 149,366 112,553 Construction 137,887 122,524 101,441 General Casualty 118,745 69,784 36,037 Allied Health 67,808 58,839 51,945 Products Liability 61,786 60,374 55,070 Small Business Property 43,893 21,002 6,160 Life Sciences 41,379 41,346 40,487 Entertainment 39,218 22,268 12,401 Energy 38,637 32,217 19,710 Professional Liability 35,743 30,313 22,626 Management Liability 26,617 28,856 28,031 Environmental 25,938 19,455 13,584 Excess Professional 24,033 22,826 21,340 Health Care 20,378 16,916 11,156 Public Entity 20,028 15,512 9,977 Commercial Auto 19,050 5,950 977 Inland Marine 18,669 14,396 9,752 Aviation 6,453 4,424 2,099 Ocean Marine 2,339 765 215 Product Recall 1,637 1,419 810 Railroad 15 — — Total commercial 1,530,338 1,067,542 737,250 Personal: Personal Insurance 24,182 31,289 27,002 High Value Homeowners 14,295 3,261 121 Total personal 38,477 34,550 27,123 Total $ 1,568,815 $ 1,102,092 $ 764,373 Certain prior year amounts are reclassified to conform to current year's divisions and the business underwritten within them. Commercial Property underwrites first-party coverage on manufacturing facilities, government and municipal buildings, professional buildings, offices and general commercial properties, vacant properties, as well as entertainment and retail facilities. Excess Casualty underwrites excess liability over risks that would fit within the general casualty, construction, products liability and small business casualty divisions. Coverage is written over the Company's primary liability policies as well as those of other insurers. This division also writes excess liability over primary commercial auto liability policies written by other carriers. Small Business Casualty underwrites commercial general liability on smaller risks, generally businesses with revenues not exceeding $2.5 million, with an emphasis on artisan contractors and premises related exposures. Construction underwrites commercial general liability coverage on contractors focusing on new residential construction, residential remodeling and renovation and commercial construction. General Casualty underwrites general liability and liquor liability on hospitality, habitational and retail risks, among others, with similar premises liability loss exposures. Allied Health underwrites commercial general liability, professional liability and excess liability on allied health and social service risks including assisted living facilities, home health care agencies and outpatient medical facilities. Products Liability underwrites commercial general liability on manufacturers, distributors and importers of a wide array of consumer, commercial and industrial products. Small Business Property underwrites Commercial Property coverage for smaller properties, generally with total insured values not exceeding $3.5 million, including banks, daycare centers, strip malls, and greenhouses, among others. Life Sciences underwrites general liability, products liability and professional liability coverage for manufacturers, distributors and developers of dietary supplements, medical devices, pharmaceuticals, biologics, health and beauty products, durable medical equipment and clinical trials. Entertainment underwrites commercial general liability for small-to-medium sized entertainment classes, including such classes as bowling alleys, campgrounds, escape rooms, fitness centers, museums and paintball facilities, among others. Energy underwrites commercial general liability, pollution liability, professional liability and excess liability on enterprises engaged in the business of energy production or distribution or mining including drillers, lease operators, contractors, product manufacturers and alternative energy. Professional Liability underwrites small-to-medium sized non-medical professional liability risks. The classes of risks include accountants, architects and engineers, financial planners, insurance agents, lawyers, realtors and certain other professions. Management Liability underwrites directors and officers liability, employment practices liability and fiduciary liability coverage on a variety of commercial and government risks. Environmental underwrites commercial general liability, pollution liability and professional liability on a wide range of commercial risks where environmental exposures exist that are operational in nature or related to the premises. Excess Professional underwrites excess coverage over an array of insurance products in Allied Health, Management Liability, Health Care and Professional Liability. Health Care underwrites medical professional liability for physicians, surgeons, dentists, chiropractors and podiatrists. Policies cover both individuals and small practice groups. Public Entity underwrites law enforcement professional liability and school board liability. Commercial Auto underwrites garage liability and excess auto coverages. Inland Marine underwrites a variety of inland marine coverages including builders risk, contractors' equipment, transportation risks and mobile equipment. Aviation underwrites general liability coverage for small-to-medium sized aviation-related businesses. Ocean Marine underwrites marine cargo coverage for small-to-medium sized risks that transport goods and products in domestic inland waterways and certain U.S. coastal waters. Product Recall underwrites recall expense and liability coverage for life sciences and general products sector consumable, commercial and consumer goods. Railroad underwrites excess liability for Class III short line railroads, railroad support activities and contractors and other miscellaneous railroad-related risks. Personal Insurance writes homeowners' coverage on manufactured homes with catastrophe exposure due to coastal location. High Value Homeowners underwrites first party homeowners' coverage on homes valued above $1.0 million on a primary and excess basis. The Company does business with three unaffiliated insurance brokers that generated $316.5 million, $286.8 million and $178.7 million of gross written premiums for the year ended December 31, 2023, representing 20.2%, 18.3% and 11.4% of gross written premiums, respectively. No other broker generated 10.0% or more of the gross written premiums for the year ended December 31, 2023.

Statutory financial information

Statutory financial information	12 Months Ended
	Dec. 31, 2023
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments [Abstract]
Statutory financial information	Statutory financial information Kinsale Insurance maintains its accounts in conformity with accounting practices prescribed or permitted by state regulatory authorities that vary in certain respects from U.S. GAAP. In converting from statutory accounting principles to U.S. GAAP, typical adjustments include deferral of policy acquisition costs, the inclusion of statutory non-admitted assets and the inclusion of net unrealized gains or losses relating to fixed maturities in stockholders’ equity. The Company does not use any permitted practices that are different from prescribed statutory accounting practices. Statutory net income and statutory capital and surplus for Kinsale Insurance as of December 31, 2023, 2022, and 2021 and for the years then ended are summarized as follows: Year ended December 31, 2023 2022 2021 (in thousands) Statutory net income $ 259,042 $ 151,105 $ 115,885 Statutory capital and surplus $ 1,167,382 $ 835,664 $ 606,910 Kinsale Insurance is subject to risk-based capital ("RBC") requirements. RBC is a method developed by the National Association of Insurance Commissioners ("NAIC") to determine the minimum amount of statutory capital appropriate for an insurance company to support its overall business operations in consideration of its size and risk profile. The formula for determining the amount of RBC is calculated using various factors, weighted based on the perceived degree of risk, which are applied to certain financial balances and financial activity. The adequacy of a company’s actual capital is evaluated by a comparison to the RBC results, as determined by the formula. Companies that do not maintain statutory capital and surplus at a level in excess of the company action level RBC are required to take specified actions. At December 31, 2023 and 2022, actual statutory capital and surplus for Kinsale Insurance substantially exceeded the regulatory requirements. Dividend payments to Kinsale from Kinsale Insurance are restricted by state insurance laws as to the amount that may be paid without prior approval of the regulatory authorities of Arkansas. The maximum dividend distribution is limited by Arkansas law to the greater of 10% of policyholder surplus as of December 31 of the previous year or statutory net income, not including realized capital gains, for the previous calendar year. Dividend payments are further limited to that part of available policyholder surplus which is derived from net profits on its business. The maximum dividend distribution that can be paid by Kinsale Insurance during 2024 without prior approval is $257.3 million.

SEC Schedule, Article 12-15, Su

SEC Schedule, Article 12-15, Summary of Investments - Other than Investments in Related Parties	12 Months Ended
	Dec. 31, 2023
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Abstract]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties	Schedule I KINSALE CAPITAL GROUP, INC. AND SUBSIDIARIES Summary of Investments—Other than Investments in Related Parties Type of Investment Cost or Amortized Cost Fair Value Amount at which shown on Balance Sheet (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 28,003 $ 27,254 $ 27,254 Obligations of states, municipalities and political subdivisions 191,080 171,044 171,044 Corporate and other securities 1,437,468 1,387,693 1,387,693 Asset-backed securities 641,700 641,760 641,760 Residential mortgage-backed securities 463,904 417,106 417,106 Commercial mortgage-backed securities 72,308 66,902 66,902 Total fixed maturities 2,834,463 2,711,759 2,711,759 Equity securities: Common stocks: ETFs (industrial, miscellaneous and all other) 65,401 106,300 106,300 Banks, trust and insurance companies 22,090 24,528 24,528 Industrial, miscellaneous and all other 67,763 70,812 70,812 Non-redeemable preferred stock 38,289 33,173 33,173 Total equity securities 193,543 234,813 234,813 Short-term investments 5,601 5,589 5,589 Real estate investments (none acquired in satisfaction of debt) 14,791 14,791 Total investments $ 3,048,398 $ 2,966,952

Schedule II - Condensed Financi

Schedule II - Condensed Financial Information of Registrant	12 Months Ended
	Dec. 31, 2023
Condensed Financial Information Disclosure [Abstract]
Condensed Financial Information of Parent Company Only Disclosure	KINSALE CAPITAL GROUP, INC. AND SUBSIDIARIES Condensed Financial Information of Registrant Balance Sheets (Parent Company Only) December 31, 2023 2022 (in thousands) Assets Cash and cash equivalents $ 17,082 $ 34,789 Due from subsidiaries 26,479 81,505 Investment in subsidiaries 1,230,371 827,911 Deferred income tax asset, net 1,673 1,301 Other assets 410 278 Total assets $ 1,276,015 $ 945,784 Liabilities and Stockholders' Equity Liabilities: Accounts payable and accrued expenses $ 2,042 $ 1,558 Income taxes payable 3,201 2,948 Debt 183,846 195,747 Other liabilities 94 82 Total liabilities 189,183 200,335 Stockholders’ equity: Common stock 232 231 Additional paid-in capital 352,970 347,015 Retained earnings 828,247 533,121 Accumulated other comprehensive income (94,617) (134,918) Stockholders’ equity 1,086,832 745,449 Total liabilities and stockholders’ equity $ 1,276,015 $ 945,784 See accompanying notes to condensed financial information. See accompanying Report of Independent Registered Public Accounting Firm. Schedule II KINSALE CAPITAL GROUP, INC. AND SUBSIDIARIES Condensed Financial Information of Registrant Statements of Income and Comprehensive Income (Parent Company Only) Years Ended December 31, 2023 2022 2021 (in thousands) Revenues: Management fees from subsidiaries $ 11,918 $ 8,686 $ 7,002 Net investment income — 121 — Net realized investment gains — 8 — Total revenues 11,918 8,815 7,002 Expenses: Operating expenses 13,007 9,765 7,972 Interest expense 10,301 4,284 994 Total expenses 23,308 14,049 8,966 Loss before income taxes (11,390) (5,234) (1,964) Income tax benefit (7,324) (5,387) (3,424) (Loss) income before equity in net income of subsidiaries (4,066) 153 1,460 Equity in net income of subsidiaries 312,159 158,961 151,199 Net income 308,093 159,114 152,659 Other comprehensive income (loss): Equity in other comprehensive earnings (losses) of subsidiaries 40,301 (153,043) (23,255) Total comprehensive income $ 348,394 $ 6,071 $ 129,404 See accompanying notes to condensed financial information. See accompanying Report of Independent Registered Public Accounting Firm. Schedule II KINSALE CAPITAL GROUP, INC. AND SUBSIDIARIES Condensed Financial Information of Registrant Statements of Cash Flows (Parent Company Only) Years Ended December 31, 2023 2022 2021 (in thousands) Operating activities Net income $ 308,093 $ 159,114 $ 152,659 Adjustments to reconcile net income to net cash (used in) provided by operating activities: Deferred tax benefit (372) (367) (347) Stock compensation expense 9,361 6,678 4,844 Equity in undistributed earnings of subsidiaries (312,159) (158,961) (151,199) Changes in operating assets and liabilities 55,893 (71,639) 3,955 Dividends received from subsidiary — — 8,000 Net cash provided by (used in) operating activities 60,816 (65,175) 17,912 Investing activities Contributions to subsidiary (50,000) (100,624) (571) Net cash used in investing activities (50,000) (100,624) (571) Financing activities Common stock issued, net of transaction costs — 47,498 — Proceeds from credit facility — 73,000 — Proceeds from notes payable 50,000 125,000 — Repayment of credit facility (62,000) (43,000) — Debt issuance costs (164) (2,381) — Payroll taxes withheld and remitted on share-based payments (4,282) (3,288) (2,101) Common stock issued, stock options exercised 877 1,090 982 Dividends paid (12,954) (11,927) (10,021) Net cash (used in) provided by financing activities (28,523) 185,992 (11,140) Net change in cash and cash equivalents (17,707) 20,193 6,201 Cash and cash equivalents at beginning of year 34,789 14,596 8,395 Cash and cash equivalents at end of year $ 17,082 $ 34,789 $ 14,596 See accompanying notes to condensed financial information. See accompanying Report of Independent Registered Public Accounting Firm. KINSALE CAPITAL GROUP, INC. Condensed Financial Information of Registrant Notes to Condensed Financial Information (Parent Company Only) 1. Accounting policies Organization Kinsale Capital Group, Inc. (the "Company"), a Delaware domiciled insurance holding company, was formed on June 3, 2009 for the purpose of acquiring and managing insurance entities. Basis of presentation The accompanying condensed financial statements have been prepared using the equity method. Under the equity method, the investment in consolidated subsidiaries is stated at cost plus equity in undistributed earnings of consolidated subsidiaries since the date of acquisition. These condensed financial statements should be read in conjunction with the Company’s consolidated financial statements. Estimates and assumptions Preparation of the condensed financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed financial statements and accompanying disclosures. Those estimates are inherently subject to change, and actual results may ultimately differ from those estimates. Debt Note Purchase and Private Shelf Agreement On July 22, 2022, the Company entered into a Note Purchase and Private Shelf Agreement (the "Note Purchase Agreement") with PGIM, Inc. ("Prudential") and the purchasers of the Series A Notes (as defined below), named in the Purchaser Schedule attached thereto (collectively, the "Note Purchasers"). Pursuant to the Note Purchase Agreement, on July 22, 2022, the Company issued $125.0 million aggregate principal amount of 5.15% Series A Senior Notes Due July 22, 2034 (collectively, the "Series A Notes") to the Note Purchasers. The Note Purchase Agreement also provides for the issuance of additional shelf notes issued thereunder (the "Shelf Notes" and, together with the Series A Notes, the "Notes") not to exceed $150.0 million of Notes outstanding thereunder. On September 18, 2023, the Company entered into a First Amendment to the Note Purchase Agreement and increased the additional Shelf Notes limit to $200.0 million. Pursuant to the First Amendment to the Note Purchase Agreement, on September 18, 2023, the Company issued a $50.0 million aggregate principal amount 6.21% Series B Senior Note due July 22, 2034 to the note purchaser. The Series A and B Notes are senior unsecured obligations of the Company and rank pari passu with the Company’s Amended and Restated Credit Agreement. The Series A Notes bear interest at 5.15% per annum and mature on July 22, 2034, unless paid earlier by the Company. Should the Company elect to prepay the Series A Notes, such aggregate prepayment will include the applicable make-whole amount(s), as defined within the applicable Note Purchase Agreement. Principal payments are required annually beginning on July 22, 2030 in equal installments of $25.0 million through July 22, 2034. The Series B Note bears interest at 6.21% per annum and matures on July 22, 2034, unless paid earlier by the Company. Should the Company elect to prepay the Series B Note, such aggregate prepayment will include the applicable make-whole amount(s), as defined within the applicable Note Purchase Agreement. Principal payments are required annually beginning on July 22, 2030 in equal installments of $10.0 million through July 22, 2034. Credit Agreement On May 28, 2019, the Company entered into a Credit Agreement (the "Credit Agreement") that provided the Company with a $50.0 million senior unsecured revolving credit facility (the "Credit Facility") and an uncommitted accordion feature that permits the Company to increase the commitments by an additional $30.0 million. On July 22, 2022, the Company entered into an Amended and Restated Credit Agreement, with JPMorgan Chase Bank, N.A., as administrative agent and as issuing bank, Truist Bank, as syndication agent, and the lenders party thereto (collectively, the "Lenders"). The Amended and Restated Credit Agreement extended the maturity date to July 22, 2027, and increased the aggregate commitment to $100.0 million, with the option to increase the aggregate commitment by $30.0 million, subject to the Company obtaining commitments from existing or new lenders and satisfying other conditions specified in the Amended and Restated Credit Agreement. The Company is required to pay a Commitment Fee Rate (as defined therein) of 0.25% on the average daily amount of the Available Revolving Commitment (as defined therein). Borrowings under the Amended and Restated Credit Agreement may be used for general corporate purposes (which may include, without limitation, to fund future growth, to finance working capital needs, to fund capital expenditures, and to refinance, redeem or repay indebtedness). In September 2023, the Company used proceeds from the sale of its real estate investment property to pay down $62.0 million from the Credit Facility. The loans under the Amended and Restated Credit Agreement bear interest, at the Company's option, at a rate equal to the Adjusted Term SOFR Rate (as defined therein) plus 1.625% or the Alternate Base Rate (as defined therein) plus 0.625%. For the year ended December 31, 2023, the annual weighted-average interest rate of borrowings under the Credit Facility was 6.84%. The following table presents the Company's outstanding debt as of December 31, 2023 and December 31, 2022: Issuance Maturities September 30, 2023 December 31, 2022 (in thousands) Credit Facility Various 7/22/2027 $ 11,000 $ 73,000 5.15% Series A Notes 7/22/2022 7/22/2034 125,000 125,000 6.21% Series B Note 9/18/2023 7/22/2034 50,000 — Less: Unamortized debt issuance costs (2,154) (2,253) Total debt $ 183,846 $ 195,747 Interest paid under both agreements totaled $10.5 million, $2.4 million and $0.9 million for the years ended December 31, 2023, 2022 and 2021, respectively. Both the Note Purchase Agreement and the Amended and Restated Credit Agreement contain representations and affirmative and negative covenants, including financial covenants customary for agreements of this type, as well as customary events of default provisions. As of December 31, 2023, the Company was in compliance with all of its financial covenants under both the Note Purchase Agreement and the Credit Facility. Dividends from subsidiary There were no cash dividends paid to Kinsale Capital Group, Inc. by its wholly-owned subsidiary, Kinsale Insurance Company for the years ended December 31, 2023 or 2022. Cash dividends paid by the insurance subsidiary were $8.0 million for the year ended December 31, 2021. Contingencies Liabilities for loss contingencies, arising from non-insurance policy claims, assessments, litigation, fines, and penalties and other sources, are recorded when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred.

Schedule V - Valuation and Qual

Schedule V - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2023
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule V - Valuation and Qualifying Accounts	Schedule V KINSALE CAPITAL GROUP, INC. AND SUBSIDIARIES Valuation and Qualifying Accounts Additions Deductions (in thousands) Balance Amounts Amounts Balance Year Ended December 31, 2023: Allowance for premiums receivable $ 8,067 $ 9,790 $ 4,474 $ 13,383 Valuation allowance for deferred tax assets 5,188 994 — 6,182 Allowance for reinsurance recoverables 459 285 — 744 Allowance for credit losses on fixed-maturity investments 366 199 12 553 Year Ended December 31, 2022: Allowance for premiums receivable 3,391 5,988 1,312 8,067 Valuation allowance for deferred tax assets 4,159 1,029 — 5,188 Allowance for reinsurance recoverables 400 59 — 459 Allowance for credit losses on fixed-maturity investments — 366 — 366 Year Ended December 31, 2021: Allowance for premiums receivable 3,087 2,189 1,885 3,391 Valuation allowance for deferred tax assets 3,491 668 — 4,159 Allowance for reinsurance recoverables 282 118 — 400

Accounting Changes and Error Co

Accounting Changes and Error Corrections	12 Months Ended
	Dec. 31, 2023
Accounting Changes and Error Corrections [Abstract]
Error Correction	Immaterial Correction to Prior Period Financial Statements for Accounting Policy Change The Company charges insureds certain policy fees and recognizes such fees into earnings when the related premium is written. Previously, the Company presented these fees as a reduction of underwriting, acquisition and insurance expenses. Effective April 1, 2023, the Company corrected its accounting policy to present these fees as fee income in the consolidated statements of income and comprehensive income in accordance with ASC 944, Financial Services–Insurance. The Company presented $27.0 million as fee income for the year ended December 31, 2023 in the consolidated statements of income and comprehensive income. The Company reclassified $19.6 million and $13.7 million to fee income from underwriting, acquisition and insurance expenses in the previously issued financial statements on Form 10-K for the years ended December 31, 2022 and 2021, respectively, to correct prior periods’ presentation. The Company considered the qualitative and quantitative impacts and determined that the correction was not material to the Company's previously issued consolidated financial statements.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net income	$ 308,093	$ 159,114	$ 152,659

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Securities Trading Plans of Directors and Executive Officers Transactions in our securities by our non-employee directors and executive officers are required to be made in accordance with our Policy on the Prevention of Insider Trading and Selective Disclosure (the "Insider Trading Policy"), which, among other things, requires that the transactions be in accordance with applicable U.S. federal securities laws that prohibit trading while in possession of material nonpublic information. Rule 10b5-1 under the Exchange Act provides an affirmative defense that enables prearranged transactions in securities in a manner that avoids concerns about initiating transactions at a future date while possibly in possession of material nonpublic information. Our Insider Trading Policy permits our non-employee directors and executive officers to enter into trading plans designed to comply with Rule 10b5-1. During the fourth quarter of 2023, none of our non-employee directors or executive officers adopted, modified or terminated a Rule 10b5-1 trading plan or adopted, modified or terminated a non-Rule 10b5-1 trading arrangement (as defined in Item 408(c) of Regulation S-K).
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Summary of significant accoun_2

Summary of significant accounting policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Principles of consolidation	Principles of consolidation The accompanying consolidated financial statements include the accounts of Kinsale Capital Group, Inc. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Certain prior year amounts have been reclassified to conform to the current year's presentation.
Use of estimates	Use of estimates
Cash and cash equivalents	Cash and cash equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents.
Short-term investments	Short-term investments
Fixed maturity and equity securities	Fixed-maturity and equity securities Fixed-maturity securities are classified as available-for-sale and reported at fair value. Unrealized gains and losses on these securities are excluded from earnings but are recorded as a separate component of other comprehensive income and stockholders' equity, net of deferred income taxes. Equity securities are reported at fair value. Changes in unrealized gains and losses in fair value of these investments are recognized in net income. The Company regularly reviews all its available-for-sale investments with unrealized losses to assess whether the decline in the fair value is deemed to be a credit loss. See Note 2 for further discussion regarding the determination of credit losses. Interest on fixed-maturity securities is credited to earnings as it accrues. Premiums and discounts are amortized or accreted using the effective interest method over the lives of the related fixed maturities, or to the earliest call date for securities purchased at a premium. This method includes an adjustment for estimated principal prepayments, if any, on asset- and mortgage-backed securities. To the extent that the estimated lives of such securities change as a result of changes in estimated prepayment rates, the adjustments are included in net investment income using the retrospective method. Dividends on equity securities are included in earnings on the ex-dividend date. Realized gains and losses on disposition of investments are based on specific identification of the investments sold on the trade date.
Investment Real Estate	Real estate investments Real estate investments include real estate and the related assets purchased for investment purposes. Real estate and the related depreciable assets are carried at cost, net of accumulated depreciation. Depreciation is calculated on a straight-line basis over the estimated useful life of the assets and is included in net investment income. Rental income is recognized on a straight-line basis over the term of the respective lease and is included in net investment income. Land is not depreciated. Real estate is evaluated for impairment when events or circumstances indicate the carrying value of the real estate may not be recoverable.
Reinsurance	Reinsurance Reinsurance premiums, commissions, and ceded unearned premiums on reinsured business are accounted for on a basis consistent with that used in accounting for the original policies issued and the terms of the reinsurance contracts. The Company receives ceding commissions in accordance with certain reinsurance treaties. The ceding commissions are capitalized and amortized as a reduction of underwriting, acquisition and insurance expenses. Reinsurance recoverables represent paid losses and loss adjustment expenses and reserves for unpaid losses and loss adjustment expenses ceded to reinsurers that are subject to reimbursement under reinsurance treaties. The method for determining reinsurance recoverables for unpaid losses and loss adjustment expenses involves reviewing actuarial estimates of gross unpaid losses and loss adjustment expenses to determine the Company's ability to cede unpaid losses and loss adjustment expenses under the Company's existing reinsurance contracts. This method is continually reviewed and updated and any resulting adjustments are reflected in earnings in the period identified. See Note 8 for a further discussion of the Company's reinsurance program.
Premiums receivable, net	Premiums receivable, net Premiums receivable balances are carried at face value, net of any allowance for credit losses. The allowance for credit losses represents an estimate of amounts considered uncollectible based on the Company’s assessment of the collectability of receivables that are past due. The estimate considers historical loss data, current and future economic conditions and specific identification of collectability concerns where applicable. The following table presents the rollforward of the allowance for credit losses for premiums receivable for the years ended December 31, 2023 and 2022: Year Ended December 31, 2023 2022 (in thousands) Beginning balance $ 8,067 $ 3,391 Current period change for estimated uncollectible premiums 9,790 5,988 Write-offs of uncollectible premiums receivable (4,474) (1,312) Ending balance $ 13,383 $ 8,067
Deferred policy acquisition costs, net of ceding commissions	Deferred policy acquisition costs, net of ceding commissions The Company defers commissions, net of ceding commissions, and certain other costs that are directly related to the successful acquisition of insurance contracts. All eligible costs are capitalized and charged to expense in proportion to premium earned over the estimated policy life. To the extent that unearned premiums on existing policies are not adequate to cover the related costs and expenses, referred to as a premium deficiency, deferred policy acquisition costs are charged to earnings. The Company considers anticipated investment income in determining whether a premium deficiency exists.
Property and equipment, net	Property and equipment, net Property and equipment are stated at cost less accumulated depreciation. Depreciation of property and equipment is calculated using the straight-line method over the estimated useful lives of the assets. The estimated useful lives range from 39 years for the building and parking deck, 15 to 20 years for land improvements, 7 to 10 years for furniture and equipment, and 3 to 7 years for electronic data processing hardware and software. Property and equipment are included in other assets in the accompanying consolidated balance sheets and consists of the following: December 31, 2023 2022 (in thousands) Building $ 37,181 $ 33,065 Parking deck 5,072 5,072 Land 3,068 3,068 Equipment 3,958 3,444 Software 15,375 11,410 Furniture and fixtures 3,065 2,615 Leasehold improvements 153 — Land improvements 474 474 Construction in progress - building 6,623 2,618 74,969 61,766 Accumulated depreciation (11,565) (8,291) Total property and equipment, net $ 63,404 $ 53,475
Indefinite-Lived intangible assets	Indefinite-lived intangible assets Indefinite-lived intangible assets are recorded at fair value at the date of acquisition. The Company's indefinite-lived intangible assets are comprised solely of regulatory approvals granted by the various state insurance departments to write insurance business in the respective states on a non-admitted basis. In accordance with U.S. GAAP, amortization of indefinite-lived intangible assets is not permitted. Indefinite-lived intangible assets are tested for impairment during the fourth quarter on an annual basis, or earlier if there is reason to suspect that their values may have been diminished or impaired. There were no impairments recognized in December 31, 2023, 2022, or 2021. In addition, as of December 31, 2023, no triggering events occurred that suggested an updated review was necessary.
Reserves for unpaid losses and loss adjustment expenses	Reserves for unpaid losses and loss adjustment expenses Reserves for unpaid losses and loss adjustment expenses represent management's best estimate of ultimate unpaid cost of all reported and unreported losses and loss adjustment expenses incurred prior to the financial statement date. The estimates are based on an actuarial method that uses management’s initial expected loss ratios, expected reporting patterns for losses based on industry data and the Company’s actual reported losses and loss adjustment expenses. All estimates are regularly reviewed and, as experience develops and new information becomes known, the reserves for unpaid losses and loss adjustment expenses are adjusted as necessary. Such adjustments are reflected in the results of operations in the period in which they are determined. Although management believes that the reserves for losses and loss adjustment expenses are reasonable, due to the inherent uncertainty in estimating reserves for unpaid losses and loss adjustment expenses, it is possible that the Company’s actual incurred losses and loss adjustment expenses will not develop in a manner consistent with the assumptions inherent in the determination of these reserves. If actual liabilities exceed recorded amounts, there will be an increase to the Company’s reserves resulting in a reduction in net income and stockholders’ equity in the period in which the deficiency is identified. Furthermore, management may determine that recorded reserves are more than adequate to cover expected losses which will result in a reduction to the reserves. The Company believes that the reserves for unpaid losses and loss adjustment expenses at December 31, 2023 and 2022 are
Revenue recognition	Revenue recognition Premiums are recognized as revenue ratably over the term of the insurance contracts, net of ceded reinsurance. Unearned premiums are calculated on a daily pro rata basis. Fee income is recognized as revenue when the related premium is written.
Income taxes	Income taxes Deferred income tax assets and liabilities are determined based on the differences between the recorded amounts and the tax bases of assets and liabilities, using enacted tax rates expected to be in effect during the year in which the basis differences reverse. The effect on deferred taxes of a change in tax rates is recognized in income in the period in which such change was enacted. Valuation allowances on deferred tax assets are estimated based on the Company's assessment of the realizability of such amounts. Valuation allowances are recorded when it is more likely than not that some portion, or all, of the deferred tax assets will not be realizable. The Company provides for uncertain tax positions, and the related interest and penalties, based upon management’s assessment of whether a tax benefit is more likely than not to be sustained upon examination by tax authorities. To the extent that the anticipated tax outcome of these uncertain tax positions changes, such changes in estimate will impact the income tax provision in the period in which such determination is made. The Company recognizes accrued interest and penalties related to uncertain tax positions as a component of income tax expense. The Company uses the portfolio approach to release stranded tax effects in accumulated other comprehensive income ("AOCI") related to its available-for-sale fixed-maturity securities. Under this approach, stranded tax effects remaining in AOCI are released only when the entire portfolio of the available-for-sale fixed-maturity securities are liquidated, sold or extinguished.
Commitments and contingencies	Contingencies Liabilities for loss contingencies, arising from noninsurance policy claims, assessments, litigation, fines, and penalties and other sources, are recorded when it is probable that a liability has been incurred and the amount of the assessment and/or remediation can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred.
Fair value of financial instruments	Fair value of financial instruments Fair value is estimated for each class of financial instrument based on the framework established in the fair value accounting guidance. This guidance requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Fair value hierarchy disclosures are based on the quality of inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). See Note 3 for further details regarding fair value disclosures.
Stock-based compensation	Stock-based compensation Stock-based compensation is expensed based upon the estimated fair value of employee stock awards. Compensation cost for awards of equity instruments to employees is measured based on the grant-date fair value of those awards and compensation expense is recognized over the service period that the awards vest. Forfeitures of stock-based compensation awards are recognized as they occur. See Note 9 for further discussion and related disclosures regarding stock-based compensation.
Prospective accounting pronouncements	Recently adopted accounting pronouncements There were no recently adopted accounting standards that had a material impact on the Company’s consolidated financial statements. Prospective accounting pronouncements ASU 2023-07, Segment Reporting - Improvements to Reportable Segment Disclosures In November 2023, the FASB issued ASU 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures," which expands reportable segment disclosure requirements by requiring disclosures of significant reportable segment expenses that are regularly provided to the Chief Operating Decision Maker ("CODM") and included within each reported measure of a segment's profit or loss. The ASU also requires disclosure of the title and position of the individual identified as the CODM and an explanation of how the CODM uses the reported measures of a segment's profit or loss in assessing segment performance and deciding how to allocate resources. Additionally, ASU 2023-07 requires all segment profit or loss and assets disclosures to be provided on an annual and interim basis. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning one year later. Early adoption is permitted and the amendments must be applied retrospectively to all prior periods presented. The Company does not expect the adoption of this guidance to materially affect the consolidated financial statements, and the Company is currently evaluating the effect the guidance will have on its disclosures.

Accounting Policies (Tables)

Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Property, Plant and Equipment	Property and equipment are included in other assets in the accompanying consolidated balance sheets and consists of the following: December 31, 2023 2022 (in thousands) Building $ 37,181 $ 33,065 Parking deck 5,072 5,072 Land 3,068 3,068 Equipment 3,958 3,444 Software 15,375 11,410 Furniture and fixtures 3,065 2,615 Leasehold improvements 153 — Land improvements 474 474 Construction in progress - building 6,623 2,618 74,969 61,766 Accumulated depreciation (11,565) (8,291) Total property and equipment, net $ 63,404 $ 53,475
Premium Receivable, Allowance for Credit Loss	The following table presents the rollforward of the allowance for credit losses for premiums receivable for the years ended December 31, 2023 and 2022: Year Ended December 31, 2023 2022 (in thousands) Beginning balance $ 8,067 $ 3,391 Current period change for estimated uncollectible premiums 9,790 5,988 Write-offs of uncollectible premiums receivable (4,474) (1,312) Ending balance $ 13,383 $ 8,067

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2023
Investments [Abstract]
Available-for-sale Investments	The following tables summarize the Company’s available-for-sale investments at December 31, 2023 and 2022: December 31, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Allowance for Credit Losses Estimated Fair Value (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 28,003 $ 57 $ (806) $ — $ 27,254 Obligations of states, municipalities and political subdivisions 191,080 212 (20,248) — 171,044 Corporate and other securities 1,437,468 5,532 (54,755) (552) 1,387,693 Asset-backed securities 641,700 2,833 (2,773) — 641,760 Residential mortgage-backed securities 463,904 1,732 (48,530) — 417,106 Commercial mortgage-backed securities 72,308 11 (5,416) (1) 66,902 Total fixed-maturity investments $ 2,834,463 $ 10,377 $ (132,528) $ (553) $ 2,711,759 December 31, 2022 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Allowance for Credit Losses Estimated Fair Value (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 17,934 $ — $ (1,193) $ — $ 16,741 Obligations of states, municipalities and political subdivisions 230,746 330 (26,444) — 204,632 Corporate and other securities 909,285 730 (76,757) (366) 832,892 Asset-backed securities 361,248 292 (8,534) — 353,006 Residential mortgage-backed securities 349,066 52 (55,156) — 293,962 Commercial mortgage-backed securities 65,353 — (6,486) — 58,867 Total fixed-maturity investments $ 1,933,632 $ 1,404 $ (174,570) $ (366) $ 1,760,100
Debt Securities, Available-for-Sale, Allowance for Credit Loss	The following table presents changes in the allowance for expected credit losses on available-for-sale securities: Years Ended December 31, 2023 2022 (in thousands) Beginning balance $ 366 $ — Increase to allowance from securities for which credit losses were not previously recorded 1 366 Reduction from securities sold during the period (12) — Net increase from securities that had an allowance at the beginning of the period 198 — Ending balance $ 553 $ 366
Available-for-sale Securities in a Unrealized Loss Position	The following tables summarize gross unrealized losses and estimated fair value for available-for-sale investments by length of time that the securities have continuously been in an unrealized loss position: December 31, 2023 Less than 12 Months 12 Months or Longer Total Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ — $ — $ 15,484 $ (806) $ 15,484 $ (806) Obligations of states, municipalities and political subdivisions 20,886 (221) 121,911 (20,027) 142,797 (20,248) Corporate and other securities 246,355 (1,444) 651,525 (53,311) 897,880 (54,755) Asset-backed securities 142,287 (872) 217,401 (1,901) 359,688 (2,773) Residential mortgage-backed securities 26,158 (49) 268,891 (48,481) 295,049 (48,530) Commercial mortgage-backed securities 8,775 (55) 56,731 (5,361) 65,506 (5,416) Total fixed-maturity investments $ 444,461 $ (2,641) $ 1,331,943 $ (129,887) $ 1,776,404 $ (132,528) December 31, 2022 Less than 12 Months 12 Months or Longer Total Estimated Fair Value Gross Unrealized Holding Losses Estimated Fair Value Gross Unrealized Holding Losses Estimated Fair Value Gross Unrealized Holding Losses (in thousands) Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 10,538 $ (447) $ 6,204 $ (746) $ 16,742 $ (1,193) Obligations of states, municipalities and political subdivisions 141,460 (20,347) 17,314 (6,097) 158,774 (26,444) Corporate and other securities 583,619 (42,675) 156,148 (34,082) 739,767 (76,757) Asset-backed securities 216,487 (5,429) 97,703 (3,105) 314,190 (8,534) Residential mortgage-backed securities 98,909 (12,324) 194,773 (42,832) 293,682 (55,156) Commercial mortgage-backed securities 50,666 (4,732) 8,201 (1,754) 58,867 (6,486) Total fixed-maturity investments $ 1,101,679 $ (85,954) $ 480,343 $ (88,616) $ 1,582,022 $ (174,570)
Contractual Maturities of Available-for-sale Fixed Maturity Securities	The amortized cost and estimated fair value of available-for-sale fixed-maturity securities at December 31, 2023 are summarized, by contractual maturity, as follows: Amortized Estimated Cost Fair Value (in thousands) Due in one year or less $ 193,054 $ 191,792 Due after one year through five years 1,051,112 1,038,158 Due after five years through ten years 184,603 167,555 Due after ten years 227,782 188,486 Asset-backed securities 641,700 641,760 Residential mortgage-backed securities 463,904 417,106 Commercial mortgage-backed securities 72,308 66,902 Total fixed maturities $ 2,834,463 $ 2,711,759
Net Investment Income	The following table presents the components of net investment income: Year Ended December 31, 2023 2022 2021 (in thousands) Interest: Taxable bonds $ 92,227 $ 44,806 $ 25,654 Municipal bonds (tax exempt) 2,217 3,380 3,501 Cash equivalents and short-term investments 3,004 1,251 12 Dividends on equity securities 5,097 4,406 3,962 Real estate investment income 3,716 234 — Gross investment income 106,261 54,077 33,129 Investment expenses (3,926) (2,795) (2,081) Net investment income $ 102,335 $ 51,282 $ 31,048
Schedule of Realized Gain (Loss)	The following table presents realized investment gains and losses: Year Ended December 31, 2023 2022 2021 (in thousands) Fixed-maturity securities: Realized gains $ 1,852 $ 1,078 $ 2,944 Realized losses (2,374) (904) (3) Net realized (losses) gains from fixed-maturity securities (522) 174 2,941 Equity securities: Realized gains 7,678 1,363 97 Realized losses (5,329) (297) (210) Net realized gains (losses) from equity securities 2,349 1,066 (113) Realized losses from the sales of short-term investments (37) (49) — Realized gain on sale of real estate investments 4,250 — — Net realized investment gains $ 6,040 $ 1,191 $ 2,828 The net realized gains or losses on sales of equity securities represent the total gains or losses from the purchase dates of the equity securities. The change in unrealized gains (losses) in the consolidated statement of income consists of two components: (1) the reversal of the gain or loss recognized in previous periods on equity securities sold and (2) the change in unrealized gain or loss resulting from mark-to-market adjustments on equity securities still held.
Schedule of Real Estate Properties	Real estate investments consisted of the following at December 31, 2023 and 2022: December 31, 2023 2022 (in thousands) Building $ — $ 44,931 Land 14,791 17,946 Intangible in-place lease — 9,749 Site improvements — 2,686 Parking deck — 1,311 14,791 76,623 Accumulated depreciation — (236) Total real estate investments, net $ 14,791 $ 76,387 During the third quarter of 2023, the Company sold the parking deck, one of the office buildings and the related in-place leases of its real estate investment property for approximately $62.0 million in cash, net of seller’s costs. The Company recognized a gain on the sale of $4.3 million, which is included in net realized investment gains on the consolidated statement of income. The Company used the net sale proceeds to pay down a portion of its Credit Facility. Concurrent with the sale of the investment property, the Company refined its plans for the remainder of the property and determined the predominant use of the remaining office building would be for future office space expansion. Upon this determination, the Company reclassified the carrying value of the building to construction in progress within property and equipment.

Fair value measurements (Tables

Fair value measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Assets Measured at Fair Value on a Recurring Basis	The following tables present the balances of assets measured at fair value on a recurring basis as of December 31, 2023 and 2022, by level within the fair value hierarchy: December 31, 2023 Level 1 Level 2 Level 3 Total (in thousands) Assets Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 22,235 $ 5,019 $ — $ 27,254 Obligations of states, municipalities and political subdivisions — 171,044 — 171,044 Corporate and other securities — 1,387,693 — 1,387,693 Asset-backed securities — 641,760 — 641,760 Residential mortgage-backed securities — 417,106 — 417,106 Commercial mortgage-backed securities — 66,902 — 66,902 Total fixed maturities 22,235 2,689,524 — 2,711,759 Equity securities: Exchange traded funds 106,300 — — 106,300 Non-redeemable preferred stock — 33,173 — 33,173 Common stocks 95,340 — — 95,340 Total equity securities 201,640 33,173 — 234,813 Short-term investments 1,862 3,727 — 5,589 Total $ 225,737 $ 2,726,424 $ — $ 2,952,161 December 31, 2022 Level 1 Level 2 Level 3 Total (in thousands) Assets Fixed maturities: U.S. Treasury securities and obligations of U.S. government agencies $ 16,741 $ — $ — $ 16,741 Obligations of states, municipalities and political subdivisions — 204,632 — 204,632 Corporate and other securities — 832,892 — 832,892 Asset-backed securities — 353,006 — 353,006 Residential mortgage-backed securities — 293,962 — 293,962 Commercial mortgage-backed securities — 58,867 — 58,867 Total fixed maturities 16,741 1,743,359 — 1,760,100 Equity securities: Exchange traded funds 104,202 — — 104,202 Non-redeemable preferred stock — 38,162 — 38,162 Common stocks 10,107 — — 10,107 Total equity securities 114,309 38,162 — 152,471 Short-term investments 31,366 9,971 — 41,337 Total $ 162,416 $ 1,791,492 $ — $ 1,953,908

Deferred policy acquisition c_2

Deferred policy acquisition costs (Tables)	12 Months Ended
	Dec. 31, 2023
Deferred Policy Acquisition Costs Disclosures [Abstract]
Deferred Policy Acquisition Costs	The following table presents the amounts of policy acquisition costs deferred and amortized for the years ended: Year Ended December 31, 2023 2022 2021 (in thousands) Balance, beginning of year $ 61,594 $ 41,968 $ 31,912 Policy acquisition costs deferred: Direct commissions 227,755 160,523 111,463 Ceding commissions (88,449) (48,022) (28,965) Other underwriting and policy acquisition costs 10,982 8,155 6,191 Policy acquisition costs deferred 150,288 120,656 88,689 Amortization of net policy acquisition costs (123,487) (101,030) (78,633) Balance, end of year $ 88,395 $ 61,594 $ 41,968

Underwriting, acquisition and_2

Underwriting, acquisition and insurance expenses (Tables)	12 Months Ended
	Dec. 31, 2023
Underwriting, Acquisition and Insurance Expenses [Abstract]
Underwriting, Acquisition and Insurance Expenses	Underwriting, acquisition and insurance expenses consist of the following: Year Ended December 31, 2023 2022 2021 (in thousands) Underwriting, acquisition and insurance expenses incurred: Direct commissions $ 198,715 $ 138,451 $ 98,847 Ceding commissions (84,998) (44,695) (25,702) Other underwriting expenses 115,253 86,566 65,448 Total $ 228,970 $ 180,322 $ 138,593

Income taxes (Tables)

Income taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Components of Income Tax Expense (Benefit)	Income tax expense includes the following components for the years ending December 31, 2023, 2022 and 2021: Year Ended December 31, 2023 2022 2021 (in thousands) Current federal income tax expense $ 85,353 $ 50,641 $ 36,718 Deferred federal income tax (benefit) expense (9,429) (14,191) (576) Income tax expense $ 75,924 $ 36,450 $ 36,142
Effective Income Tax Rate Reconciliation	The Company’s effective income tax rate on income before income taxes differs from the prevailing federal income tax rate and is summarized as follows: Year ended December 31, 2023 2022 2021 (in thousands) Income tax expense at federal income tax rate $ 80,644 $ 41,068 $ 39,648 Stock options exercised (3,676) (3,240) (2,148) Restricted stock award vesting (1,256) (1,048) (677) Tax-exempt investment income (347) (527) (546) Other 559 197 (135) Total $ 75,924 $ 36,450 $ 36,142
Deferred Tax Assets and Liabilities	The significant components of the net deferred tax asset are summarized as follows: December 31, 2023 2022 (in thousands) Deferred tax assets: Unrealized losses on fixed-maturity securities $ 25,655 $ 36,370 Unpaid losses and loss adjustment expenses 27,422 20,256 Unearned premiums 27,251 19,183 State operating loss carryforwards 6,012 5,351 Stock compensation 2,155 1,521 Allowance for credit losses 2,810 1,694 Other 2,394 474 Deferred tax assets before allowance 93,699 84,849 Less: valuation allowance (6,182) (5,188) Total deferred tax assets 87,517 79,661 Deferred tax liabilities: Unrealized gains on equity securities 8,667 5,459 Deferred policy acquisition costs, net of ceding commissions 18,563 12,935 Property and equipment 3,005 2,670 Other 1,583 1,614 Total deferred tax liabilities 31,818 22,678 Net deferred tax asset $ 55,699 $ 56,983

Reserves for unpaid losses an_2

Reserves for unpaid losses and loss adjustment expenses (Tables)	12 Months Ended
	Dec. 31, 2023
Liability for Claims and Claims Adjustment Expense [Abstract]
Unpaid Losses and Loss Adjustment Expenses	The following table presents a reconciliation of consolidated beginning and ending reserves for unpaid losses and loss adjustment expenses: December 31, 2023 2022 2021 (in thousands) Gross reserves for unpaid losses and loss adjustment expenses, beginning of year $ 1,238,402 $ 881,344 $ 636,013 Less: reinsurance recoverable on unpaid losses 177,039 117,561 83,730 Net reserves for unpaid losses and loss adjustment expenses, beginning of year 1,061,363 763,783 552,283 Incurred losses and loss adjustment expenses: Current year 635,993 493,800 356,401 Prior years (35,774) (35,887) (31,986) Total net losses and loss adjustment expenses incurred 600,219 457,913 324,415 Payments: Current year 38,565 49,205 23,765 Prior years 171,499 111,128 89,150 Total payments 210,064 160,333 112,915 Net reserves for unpaid losses and loss adjustment expenses, end of year 1,451,518 1,061,363 763,783 Reinsurance recoverable on unpaid losses, net of allowance 241,357 177,039 117,561 Gross reserves for unpaid losses and loss adjustment expenses, end of year $ 1,692,875 $ 1,238,402 $ 881,344
Claims Development
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability	The reconciliation of the net incurred and paid claims development tables to the liability for unpaid claims and claim adjustment expenses in the consolidated statement of financial position is as follows: (in thousands) December 31, 2023 Net outstanding liabilities Property $ 66,579 Casualty - claims made 244,880 Casualty - occurrence 989,992 Liabilities for unpaid claims and claim adjustment expenses, net of reinsurance 1,301,451 Reinsurance recoverable on unpaid claims Property 60,888 Casualty - claims made 21,393 Casualty - occurrence 159,820 Allowance for credit losses (744) Total reinsurance recoverable on unpaid claims 241,357 Unallocated claims adjustment expenses 149,323 Allowance for credit losses 744 Gross liability for unpaid claims and claim adjustment expense $ 1,692,875
Property [Member]
Claims Development
Short-duration Insurance Contracts, Claims Development	Property Incurred Claims and Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, As of December 31, 2023 Accident Year 2019 2020 2021 2022 2023 Total of IBNR Liabilities Plus Expected Development on Reported Claims Cumulative Number of Reported Claims ($ in thousands) 2019 $ 14,914 $ 13,909 $ 15,572 $ 16,748 $ 15,357 $ — 643 2020 40,612 37,939 36,807 37,078 214 2,309 2021 36,531 33,518 29,750 1,403 1,144 2022 67,127 53,676 4,744 2,330 2023 75,517 47,874 902 Total $ 211,378 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Accident Year 2019 2020 2021 2022 2023 ($ in thousands) 2019 $ 9,852 $ 12,581 $ 13,996 $ 14,511 $ 15,223 2020 19,897 30,321 31,765 35,023 2021 14,268 21,257 27,324 2022 33,004 46,965 2023 20,267 Total 144,802 All outstanding liabilities before 2019, net of reinsurance 3 Liabilities for claims and claim adjustment expenses, net of reinsurance $ 66,579
Short-duration Insurance Contracts, Schedule of Historical Claims Duration	The following is supplementary information about average historical claims duration as of December 31, 2023: Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Unaudited) Years 1 2 3 4 5 Property 50.8 % 23.8 % 11.2 % 6.1 % 4.6 %
Casualty - claims made [Member]
Claims Development
Short-duration Insurance Contracts, Claims Development	Casualty - Claims Made Incurred Claims and Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, As of December 31, 2023 Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 Total of IBNR Liabilities Plus Expected Development on Reported Claims Cumulative Number of Reported Claims ($ in thousands) 2014 $ 18,847 $ 14,289 $ 11,748 $ 11,217 $ 10,948 $ 10,988 $ 10,620 $ 10,266 $ 9,880 $ 9,868 $ 177 273 2015 18,883 16,777 14,896 13,583 13,942 13,548 13,414 13,066 12,759 93 259 2016 19,170 14,693 14,675 14,322 13,583 13,602 13,228 12,707 16 311 2017 18,116 17,097 16,120 15,794 14,989 13,698 13,471 661 372 2018 22,429 20,234 18,612 17,057 14,411 14,272 1,346 465 2019 34,693 29,056 26,426 24,489 21,788 4,227 562 2020 55,630 44,641 38,287 33,667 13,458 784 2021 84,018 66,191 52,935 36,436 1,077 2022 101,064 81,394 59,239 1,205 2023 115,858 98,185 1,336 Total $ 368,719 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 ($ in thousands) 2014 $ 435 $ 1,865 $ 5,039 $ 6,385 $ 8,290 $ 9,415 $ 9,491 $ 9,628 $ 9,638 $ 9,691 2015 217 4,496 7,563 9,238 11,372 11,522 12,142 12,463 12,474 2016 1,158 3,015 6,907 9,839 11,381 12,105 12,299 12,691 2017 340 4,897 8,252 10,484 11,357 12,235 12,335 2018 507 5,030 8,931 10,330 11,205 12,623 2019 2,487 6,005 10,123 14,476 15,406 2020 1,002 7,446 12,551 18,589 2021 1,146 8,437 12,895 2022 3,052 12,381 2023 4,830 Total 123,915 All outstanding liabilities before 2014, net of reinsurance 76 Liabilities for claims and claim adjustment expenses, net of reinsurance $ 244,880
Casualty - occurrence [Member]
Claims Development
Short-duration Insurance Contracts, Claims Development	Casualty - Occurrence Incurred Claims and Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, As of December 31, 2023 Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 Total of IBNR Liabilities Plus Expected Development on Reported Claims Cumulative Number of Reported Claims ($ in thousands) 2014 $ 47,805 $ 40,668 $ 38,049 $ 36,678 $ 39,313 $ 41,859 $ 42,434 $ 41,367 $ 41,677 $ 41,820 $ 2,546 1,261 2015 59,717 51,739 49,122 52,100 54,697 54,090 54,090 54,637 55,259 4,062 1,913 2016 61,440 55,680 53,549 55,534 57,401 60,861 64,612 65,323 6,331 1,640 2017 71,126 67,151 68,985 70,641 71,117 69,911 76,715 10,589 2,141 2018 86,157 78,331 78,386 83,952 93,215 97,005 17,691 2,380 2019 112,266 109,994 108,138 107,480 115,681 35,995 2,370 2020 154,619 136,212 131,082 135,045 86,636 2,681 2021 200,598 190,879 193,722 144,372 2,827 2022 272,692 271,399 227,940 3,064 2023 372,245 358,062 2,195 Total $ 1,424,214 Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, Accident Year 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 ($ in thousands) 2014 $ 698 $ 3,081 $ 8,489 $ 17,576 $ 23,771 $ 31,026 $ 34,338 $ 35,807 $ 37,375 $ 38,169 2015 941 3,161 12,685 28,385 37,690 41,724 44,161 47,106 49,147 2016 1,099 6,015 17,225 28,924 34,437 43,311 51,533 55,595 2017 1,581 9,352 22,407 37,736 46,025 52,069 61,108 2018 2,638 10,995 22,860 35,138 54,441 72,174 2019 3,944 16,687 30,518 46,478 69,384 2020 2,400 8,673 17,805 32,606 2021 3,205 12,944 31,494 2022 4,658 23,084 2023 4,329 Total 437,090 All outstanding liabilities before 2014, net of reinsurance 2,868 Liabilities for claims and claim adjustment expenses, net of reinsurance $ 989,992
Casualty [Member]
Claims Development
Short-duration Insurance Contracts, Schedule of Historical Claims Duration	The following is supplementary information about average historical claims duration as of December 31, 2023: Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance (Unaudited) Years 1 2 3 4 5 6 7 8 9 10 Casualty - claims made 4.6 % 21.0 % 22.7 % 16.3 % 10.8 % 6.9 % 2.0 % 2.3 % 0.1 % 0.5 % Casualty - occurrence 2.0 % 7.1 % 13.1 % 17.9 % 15.1 % 12.9 % 9.2 % 5.0 % 3.7 % 1.9 %

Reinsurance (Tables)

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2023
Reinsurance Disclosures [Abstract]
Effects of Reinsurance on Premiums Written and Earned	The following table summarizes the effect of reinsurance on premiums written and earned: Year Ended December 31, 2023 2022 2021 (in thousands) Written: Direct $ 1,568,815 $ 1,102,092 $ 764,373 Ceded (304,185) (165,282) (104,164) Net written $ 1,264,630 $ 936,810 $ 660,209 Earned: Direct $ 1,367,141 $ 950,145 $ 677,630 Ceded (294,604) (156,026) (94,751) Net earned $ 1,072,537 $ 794,119 $ 582,879
Reinsurance Recoverables	The following table presents reinsurance recoverables on paid and unpaid losses as of December 31, 2023 and 2022: December 31, 2023 December 31, 2022 (in thousands) Reinsurance recoverables on paid losses $ 6,479 $ 43,415 Reinsurance recoverables on unpaid losses 241,357 177,039 Reinsurance recoverables $ 247,836 $ 220,454

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Equity, Attributable to Parent [Abstract]
Share-based Compensation, Stock Options, Activity	A summary of option activity as of December 31, 2023 and changes during the year then ended is presented below: Number of Shares Weighted-average exercise price Weighted-average remaining years of contractual life Aggregate intrinsic value (in thousands) Outstanding at December 31, 2022 256,357 $ 16.00 Granted — — Forfeited — — Exercised (54,797) 16.00 Outstanding at December 31, 2023 201,560 $ 16.00 2.6 $ 64,280 Exercisable at December 31, 2023 201,560 $ 16.00 2.6 $ 64,280
Nonvested Restricted Stock Shares Activity	A summary of restricted stock activity under the equity compensation plans for the year ended is as follows: December 31, 2023 Number of Shares Weighted Average Grant Date Fair Value per Share Nonvested outstanding at the beginning of the period 98,621 $ 182.37 Granted 51,176 $ 313.35 Vested (40,951) $ 163.98 Forfeited (1,024) $ 252.44 Nonvested outstanding at the end of the period 107,822 $ 250.86

Earnings per share (Tables)

Earnings per share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Earnings Per Share	The following table represents a reconciliation of the numerator and denominator of the basic and diluted earnings per share computations contained in the consolidated financial statements: Year ended December 31, 2023 2022 2021 (in thousands, except per share data) Net income $ 308,093 $ 159,114 $ 152,659 Weighted average common shares outstanding - basic 23,045 22,815 22,693 Dilutive effect of shares issued under stock compensation arrangements: Stock options 214 269 324 Restricted stock awards 48 41 45 Total dilutive effect of shares issued under stock compensation arrangements 262 310 369 Weighted average common shares outstanding - diluted 23,307 23,125 23,062 Earnings per common share: Basic $ 13.37 $ 6.97 $ 6.73 Diluted $ 13.22 $ 6.88 $ 6.62

Other comprehensive income (l_2

Other comprehensive income (loss) (Tables)	12 Months Ended
	Dec. 31, 2023
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other Comprehensive Income (Loss)	The following table summarizes the components of other comprehensive income (loss): Year Ending December 31, 2023 2022 2021 (in thousands) Unrealized gains (losses) on fixed-maturity securities arising during the period, before income taxes: $ 49,384 $ (193,970) $ (26,792) Income tax (expense) benefit (10,371) 40,734 5,626 Unrealized gains (losses) arising during the period, net of income taxes 39,013 (153,236) (21,166) Less reclassification adjustment: Net realized investment (losses) gains on available-for-sale investments (1,443) 121 2,644 Income tax benefit (expense) 303 (25) (555) Reclassification adjustment included in net income (1,140) 96 2,089 Change in allowance for credit losses on investments, before income taxes (187) (366) — Income tax benefit 39 77 — Reclassification adjustment included in net income (148) (289) — Other comprehensive income (loss) $ 40,301 $ (153,043) $ (23,255)

Underwriting information (Table

Underwriting information (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting [Abstract]
Gross Written Premiums by Underwriting Division	Gross written premiums by underwriting division are presented below: Year Ended December 31, 2023 2022 2021 (in thousands) Commercial: Commercial Property $ 411,956 $ 181,505 $ 72,392 Excess Casualty 194,049 147,485 108,487 Small Business Casualty 174,080 149,366 112,553 Construction 137,887 122,524 101,441 General Casualty 118,745 69,784 36,037 Allied Health 67,808 58,839 51,945 Products Liability 61,786 60,374 55,070 Small Business Property 43,893 21,002 6,160 Life Sciences 41,379 41,346 40,487 Entertainment 39,218 22,268 12,401 Energy 38,637 32,217 19,710 Professional Liability 35,743 30,313 22,626 Management Liability 26,617 28,856 28,031 Environmental 25,938 19,455 13,584 Excess Professional 24,033 22,826 21,340 Health Care 20,378 16,916 11,156 Public Entity 20,028 15,512 9,977 Commercial Auto 19,050 5,950 977 Inland Marine 18,669 14,396 9,752 Aviation 6,453 4,424 2,099 Ocean Marine 2,339 765 215 Product Recall 1,637 1,419 810 Railroad 15 — — Total commercial 1,530,338 1,067,542 737,250 Personal: Personal Insurance 24,182 31,289 27,002 High Value Homeowners 14,295 3,261 121 Total personal 38,477 34,550 27,123 Total $ 1,568,815 $ 1,102,092 $ 764,373

Statutory financial informati_2

Statutory financial information (Tables)	12 Months Ended
	Dec. 31, 2023
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments [Abstract]
Statutory Net Income and Statutory Capital and Surplus	Statutory net income and statutory capital and surplus for Kinsale Insurance as of December 31, 2023, 2022, and 2021 and for the years then ended are summarized as follows: Year ended December 31, 2023 2022 2021 (in thousands) Statutory net income $ 259,042 $ 151,105 $ 115,885 Statutory capital and surplus $ 1,167,382 $ 835,664 $ 606,910

Schedule II - Condensed Finan_2

Schedule II - Condensed Financial Information of Registrant (Tables)	12 Months Ended
	Dec. 31, 2023
Condensed Financial Information Disclosure [Abstract]
Condensed Balance Sheet	December 31, 2023 2022 (in thousands) Assets Cash and cash equivalents $ 17,082 $ 34,789 Due from subsidiaries 26,479 81,505 Investment in subsidiaries 1,230,371 827,911 Deferred income tax asset, net 1,673 1,301 Other assets 410 278 Total assets $ 1,276,015 $ 945,784 Liabilities and Stockholders' Equity Liabilities: Accounts payable and accrued expenses $ 2,042 $ 1,558 Income taxes payable 3,201 2,948 Debt 183,846 195,747 Other liabilities 94 82 Total liabilities 189,183 200,335 Stockholders’ equity: Common stock 232 231 Additional paid-in capital 352,970 347,015 Retained earnings 828,247 533,121 Accumulated other comprehensive income (94,617) (134,918) Stockholders’ equity 1,086,832 745,449 Total liabilities and stockholders’ equity $ 1,276,015 $ 945,784
Condensed Income Statement	Years Ended December 31, 2023 2022 2021 (in thousands) Revenues: Management fees from subsidiaries $ 11,918 $ 8,686 $ 7,002 Net investment income — 121 — Net realized investment gains — 8 — Total revenues 11,918 8,815 7,002 Expenses: Operating expenses 13,007 9,765 7,972 Interest expense 10,301 4,284 994 Total expenses 23,308 14,049 8,966 Loss before income taxes (11,390) (5,234) (1,964) Income tax benefit (7,324) (5,387) (3,424) (Loss) income before equity in net income of subsidiaries (4,066) 153 1,460 Equity in net income of subsidiaries 312,159 158,961 151,199 Net income 308,093 159,114 152,659 Other comprehensive income (loss): Equity in other comprehensive earnings (losses) of subsidiaries 40,301 (153,043) (23,255) Total comprehensive income $ 348,394 $ 6,071 $ 129,404
Condensed Cash Flow Statement	Years Ended December 31, 2023 2022 2021 (in thousands) Operating activities Net income $ 308,093 $ 159,114 $ 152,659 Adjustments to reconcile net income to net cash (used in) provided by operating activities: Deferred tax benefit (372) (367) (347) Stock compensation expense 9,361 6,678 4,844 Equity in undistributed earnings of subsidiaries (312,159) (158,961) (151,199) Changes in operating assets and liabilities 55,893 (71,639) 3,955 Dividends received from subsidiary — — 8,000 Net cash provided by (used in) operating activities 60,816 (65,175) 17,912 Investing activities Contributions to subsidiary (50,000) (100,624) (571) Net cash used in investing activities (50,000) (100,624) (571) Financing activities Common stock issued, net of transaction costs — 47,498 — Proceeds from credit facility — 73,000 — Proceeds from notes payable 50,000 125,000 — Repayment of credit facility (62,000) (43,000) — Debt issuance costs (164) (2,381) — Payroll taxes withheld and remitted on share-based payments (4,282) (3,288) (2,101) Common stock issued, stock options exercised 877 1,090 982 Dividends paid (12,954) (11,927) (10,021) Net cash (used in) provided by financing activities (28,523) 185,992 (11,140) Net change in cash and cash equivalents (17,707) 20,193 6,201 Cash and cash equivalents at beginning of year 34,789 14,596 8,395 Cash and cash equivalents at end of year $ 17,082 $ 34,789 $ 14,596

Description of business - (Deta

Description of business - (Details)	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of states in which company is authorized to write business	50

Summary of significant accoun_3

Summary of significant accounting policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Premium Receivable, Allowance for Credit Loss, Beginning Balance	$ 8,067	$ 3,391
Premium Receivable, Credit Loss Expense (Reversal)	9,790	5,988
Premium Receivable, Allowance for Credit Loss, Writeoff	(4,474)	(1,312)
Premium Receivable, Allowance for Credit Loss	$ 13,383	$ 8,067

Intangible assets and other inf

Intangible assets and other information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Excess and surplus lines insurance authorization [Member]
Indefinite-lived Intangible Assets [Line Items]
Impairment of intangible assets	$ 0	$ 0	$ 0

Summary of significant accoun_4

Summary of significant accounting policies Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 74,969	$ 61,766
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(11,565)	(8,291)
Property, Plant and Equipment, Net	63,404	53,475
Building [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 37,181	33,065
Building [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	39 years
Parking [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 5,072	5,072
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,068	3,068
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3,958	3,444
Software Development [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	15,375	11,410
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 3,065	2,615
Furniture and Fixtures [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	7 years
Furniture and Fixtures [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	10 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 153	0
Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 474	474
Land Improvements [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	15 years
Land Improvements [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	20 years
Technology Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Technology Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life	7 years
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 6,623	$ 2,618

Investments, Available-for-sale

Investments, Available-for-sale Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	$ 2,834,463	$ 1,933,632
Gross Unrealized Gains	10,377	1,404
Gross Unrealized Losses	132,528	174,570
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	(553)	(366)	$ 0
Estimated Fair Value	2,711,759	1,760,100
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	28,003	17,934
Gross Unrealized Gains	57	0
Gross Unrealized Losses	806	1,193
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Estimated Fair Value	27,254	16,741
Obligations of states, municipalities and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	191,080	230,746
Gross Unrealized Gains	212	330
Gross Unrealized Losses	20,248	26,444
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Estimated Fair Value	171,044	204,632
Corporate and other securities [Member]
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	1,437,468	909,285
Gross Unrealized Gains	5,532	730
Gross Unrealized Losses	54,755	76,757
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	(552)	(366)
Estimated Fair Value	1,387,693	832,892
Asset-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	641,700	361,248
Gross Unrealized Gains	2,833	292
Gross Unrealized Losses	2,773	8,534
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Estimated Fair Value	641,760	353,006
Residential mortgage-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	463,904	349,066
Gross Unrealized Gains	1,732	52
Gross Unrealized Losses	48,530	55,156
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Estimated Fair Value	417,106	293,962
Commercial mortgage-backed aecurities [Member]
Debt Securities, Available-for-sale [Line Items]
Total fixed maturities, Amortized Cost	72,308	65,353
Gross Unrealized Gains	11	0
Gross Unrealized Losses	5,416	6,486
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	(1)	0
Estimated Fair Value	$ 66,902	$ 58,867

Investments, Available-for-sa_2

Investments, Available-for-sale Securities in a Loss Position (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Rate	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	$ 444,461	$ 1,101,679
Less than 12 months, Gross Unrealized Losses	2,641	85,954
12 Months or Longer, Estimated Fair Value	1,331,943	480,343
12 Months or Longer, Gross Unrealized Losses	129,887	88,616
Total Estimated Fair Value	1,776,404	1,582,022
Total gross unrealized losses	(132,528)	(174,570)
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 1,776,404	1,582,022
Number of available-for-sale securities in unrealized loss positions	967
Number of available-for-sale securities in unrealized loss positions, greater than one year	758
Debt Securities, Available-for-Sale, Excluding Accrued Interest, Allowance for Credit Loss, Not Previously Recorded	$ 1	366
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Securities Sold	(12)	0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Period Increase (Decrease)	198	0
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	$ 553	366	$ 0
Debt Securities Available For Sale Allowance For Credit Loss Number Of Securities	6
Fixed Maturities [Member]
Debt Securities, Available-for-sale [Line Items]
Percentage of securities rated A- or better | Rate	83.30%
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	$ 0	10,538
Less than 12 months, Gross Unrealized Losses	0	447
12 Months or Longer, Estimated Fair Value	15,484	6,204
12 Months or Longer, Gross Unrealized Losses	806	746
Total Estimated Fair Value	15,484	16,742
Total gross unrealized losses	(806)	(1,193)
Debt Securities, Available-for-Sale, Unrealized Loss Position	15,484	16,742
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Obligations of states, municipalities and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	20,886	141,460
Less than 12 months, Gross Unrealized Losses	221	20,347
12 Months or Longer, Estimated Fair Value	121,911	17,314
12 Months or Longer, Gross Unrealized Losses	20,027	6,097
Total Estimated Fair Value	142,797	158,774
Total gross unrealized losses	(20,248)	(26,444)
Debt Securities, Available-for-Sale, Unrealized Loss Position	142,797	158,774
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Corporate and other securities [Member]
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	246,355	583,619
Less than 12 months, Gross Unrealized Losses	1,444	42,675
12 Months or Longer, Estimated Fair Value	651,525	156,148
12 Months or Longer, Gross Unrealized Losses	53,311	34,082
Total Estimated Fair Value	897,880	739,767
Total gross unrealized losses	(54,755)	(76,757)
Debt Securities, Available-for-Sale, Unrealized Loss Position	897,880	739,767
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	552	366
Asset-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	142,287	216,487
Less than 12 months, Gross Unrealized Losses	872	5,429
12 Months or Longer, Estimated Fair Value	217,401	97,703
12 Months or Longer, Gross Unrealized Losses	1,901	3,105
Total Estimated Fair Value	359,688	314,190
Total gross unrealized losses	(2,773)	(8,534)
Debt Securities, Available-for-Sale, Unrealized Loss Position	359,688	314,190
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Residential mortgage-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	26,158	98,909
Less than 12 months, Gross Unrealized Losses	49	12,324
12 Months or Longer, Estimated Fair Value	268,891	194,773
12 Months or Longer, Gross Unrealized Losses	48,481	42,832
Total Estimated Fair Value	295,049	293,682
Total gross unrealized losses	(48,530)	(55,156)
Debt Securities, Available-for-Sale, Unrealized Loss Position	295,049	293,682
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0	0
Commercial mortgage-backed aecurities [Member]
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months, Estimated Fair Value	8,775	50,666
Less than 12 months, Gross Unrealized Losses	55	4,732
12 Months or Longer, Estimated Fair Value	56,731	8,201
12 Months or Longer, Gross Unrealized Losses	5,361	1,754
Total Estimated Fair Value	65,506	58,867
Total gross unrealized losses	(5,416)	(6,486)
Debt Securities, Available-for-Sale, Unrealized Loss Position	65,506	58,867
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	$ 1	$ 0

Investments, Contractual Maturi

Investments, Contractual Maturities of Available-for-sale Fixed Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost [Abstract]
Due in one year or less, Amortized Cost	$ 193,054
Due after one year through five years, Amortized Cost	1,051,112
Due after five years through ten years, Amortized Cost	184,603
Due after ten years, Amortized Cost	227,782
Total fixed maturities, Amortized Cost	2,834,463	$ 1,933,632
Estimated Fair Value [Abstract]
Due in one year or less, Estimated Fair Value	191,792
Due after one year through five years, Estimated Fair Value	1,038,158
Due after five years through ten years, Estimated Fair Value	167,555
Due after ten years, Estimated Fair Value	188,486
Estimated Fair Value	2,711,759	1,760,100
Asset-backed securities [Member]
Amortized Cost [Abstract]
Without single maturity date, Amortized Cost	641,700
Total fixed maturities, Amortized Cost	641,700	361,248
Estimated Fair Value [Abstract]
Without single maturity date, Estimated Fair Value	641,760
Estimated Fair Value	641,760	353,006
Residential mortgage-backed securities [Member]
Amortized Cost [Abstract]
Without single maturity date, Amortized Cost	463,904
Total fixed maturities, Amortized Cost	463,904	349,066
Estimated Fair Value [Abstract]
Without single maturity date, Estimated Fair Value	417,106
Estimated Fair Value	417,106	293,962
Commercial mortgage-backed aecurities [Member]
Amortized Cost [Abstract]
Without single maturity date, Amortized Cost	72,308
Total fixed maturities, Amortized Cost	72,308	65,353
Estimated Fair Value [Abstract]
Without single maturity date, Estimated Fair Value	66,902
Estimated Fair Value	$ 66,902	$ 58,867

Investments, Net Investment Inc

Investments, Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Interest [Abstract]
Taxable bonds	$ 92,227	$ 44,806	$ 25,654
Municipal bonds (tax exempt)	2,217	3,380	3,501
Cash equivalents and short-term investments	3,004	1,251	12
Dividends on equity securities	5,097	4,406	3,962
Real estate investment income	106,261	54,077	33,129
Investment expenses	(3,926)	(2,795)	(2,081)
Net investment income	102,335	51,282	31,048
Real Estate Investment
Interest [Abstract]
Real estate investment income	3,716	234	0
Investment expenses	$ (500)	$ (200)	$ 0

Investments Realized Investment

Investments Realized Investment Gains and Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fixed-maturity securities - realized gains (losses) [Abstract]
Realized gains	$ 1,852	$ 1,078	$ 2,944
Realized losses	(2,374)	(904)	(3)
Net realized gains from fixed-maturity securities	(522)	174	2,941
Equity securities - realized gains (losses) [Abstract]
Realized gains	7,678	1,363	97
Realized losses	(5,329)	(297)	(210)
Net realized gains (losses) from equity securities	2,349	1,066	(113)
SalesOfShort-termAndOtherSecuritiesNetRealizedGains(Losses)	(37)	(49)	0
Gains (Losses) on Sales of Investment Real Estate	4,250	0	0
Gain (Loss) on Investments, Total	$ 6,040	$ 1,191	$ 2,828

Investments, Unrealized Gain (L

Investments, Unrealized Gain (Losses) on Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Change in unrealized gains (losses), fixed-maturity securities	$ 51	$ (193.7)	$ (29.4)

Investments Investment Deposits

Investments Investment Deposits and Payables (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Invested assets on deposit with state regulatory authorities	$ 5.8	$ 5.9
Payable for investments purchased	$ 12.3	$ 1.8

Investments (Details), Real Est

Investments (Details), Real Estate - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Real Estate Properties [Line Items]
Investment Building and Building Improvements	$ 0	$ 44,931
Land	14,791	17,946
Finite-Lived Intangible Asset, Acquired-in-Place Leases	0	9,749
Land Improvements	0	2,686
Investment in Real Estate - Parking deck	0	1,311
Real Estate Investment Property, at Cost	14,791	76,623
Real Estate Investment Property, Accumulated Depreciation	0	(236)
Real Estate Investments, Net	14,791	76,387
Gains (Losses) on Sales of Investment Real Estate	4,250	0	$ 0
Proceeds from Sale, Real Estate, Held-for-Investment	62,000
Investment Income, Investment Expense	3,926	2,795	2,081
Real Estate Investment
Real Estate Properties [Line Items]
Investment Income, Investment Expense	$ 500	$ 200	$ 0

Fair value measurements (Detail

Fair value measurements (Details) - Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 2,952,161	$ 1,953,908
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	225,737	162,416
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	2,726,424	1,791,492
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Fixed Maturities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	2,711,759	1,760,100
Fixed Maturities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	22,235	16,741
Fixed Maturities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	2,689,524	1,743,359
Fixed Maturities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
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]
Estimated Fair Value	27,254	16,741
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	22,235	16,741
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	5,019	0
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Obligations of states, municipalities and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	171,044	204,632
Obligations of states, municipalities and political subdivisions [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Obligations of states, municipalities and political subdivisions [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	171,044	204,632
Obligations of states, municipalities and political subdivisions [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Corporate and other securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	1,387,693	832,892
Corporate and other securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Corporate and other securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	1,387,693	832,892
Corporate and other securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Asset-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	641,760	353,006
Asset-backed securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Asset-backed securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	641,760	353,006
Asset-backed securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	417,106	293,962
Residential mortgage-backed securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Residential mortgage-backed securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	417,106	58,867
Residential mortgage-backed securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Commercial mortgage-backed aecurities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	66,902	58,867
Commercial mortgage-backed aecurities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Commercial mortgage-backed aecurities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	66,902	293,962
Commercial mortgage-backed aecurities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0	0
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	234,813	152,471
Equity Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	201,640	114,309
Equity Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	33,173	38,162
Equity Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Exchange Traded Fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	106,300	104,202
Exchange Traded Fund [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	106,300	104,202
Exchange Traded Fund [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Exchange Traded Fund [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Nonredeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	33,173	38,162
Nonredeemable Preferred Stock [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Nonredeemable Preferred Stock [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	33,173	38,162
Nonredeemable Preferred Stock [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	95,340	10,107
Common Stock [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	95,340	10,107
Common Stock [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Common Stock [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Short-Term Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	5,589	41,337
Short-Term Investments | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	1,862	31,366
Short-Term Investments | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,727	9,971
Short-Term Investments | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 0	$ 0

Fair value measurements 2 (Deta

Fair value measurements 2 (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents, Fair Value Disclosure	$ 11,800,000	$ 58,000,000
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured at fair value on a nonrecurring basis	0	0
Liabilities measured at fair value on a nonrecurring basis	0	0
Reported Value Measurement | Senior Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-Term Debt, Fair Value	175,000,000	125,000,000
Estimate of Fair Value Measurement | Senior Notes | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-Term Debt, Fair Value	$ 171,600,000	$ 117,200,000

Deferred policy acquisition c_3

Deferred policy acquisition costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Movement analysis of deferred policy acquisition costs [Roll Forward]
Balance, beginning of period	$ 61,594	$ 41,968	$ 31,912
Policy acquisition costs deferred:
Direct commissions deferred	227,755	160,523	111,463
Ceding commissions deferred	(88,449)	(48,022)	(28,965)
Other underwriting and policy acquisition costs deferred	10,982	8,155	6,191
Policy acquisition costs deferred	150,288	120,656	88,689
Amortization of net policy acquisition costs	(123,487)	(101,030)	(78,633)
Balance, end of period	$ 88,395	$ 61,594	$ 41,968

Underwriting, acquisition and_3

Underwriting, acquisition and insurance expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Underwriting, Acquisition and Insurance Expenses [Abstract]
Direct commissions	$ 198,715	$ 138,451	$ 98,847
Ceding commissions	(84,998)	(44,695)	(25,702)
Other expenses	115,253	86,566	65,448
Total	228,970	180,322	138,593
Salaries, employee benefits and bonus expense	$ 85,700	$ 64,800	$ 48,900

Income taxes (Details)

Income taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of income tax expense
Current federal income tax expense	$ 85,353	$ 50,641	$ 36,718
Deferred federal income tax benefit	(9,429)	(14,191)	(576)
Income tax expense	75,924	36,450	36,142
Federal income taxes paid	$ 84,600	$ 43,100	40,600
Statutory income tax rate, percent	21%	21%
Effective income tax rate reconciliation, amount [Abstract]
Income tax expense at federal income tax	$ 80,644	$ 41,068	39,648
Stock options exercised	(3,676)	(3,240)	2,148
Restricted stock award vesting	(1,256)	(1,048)	(677)
Tax-exempt investment income	(347)	(527)	(546)
Other	559	197	(135)
Income tax expense	75,924	36,450	$ 36,142
Unrecognized tax positions	0	0
Taxes Payable	$ 3,200	$ 2,500

Income taxes - Deferred Tax Ass

Income taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets [Abstract]
Deferred Tax Assets, Investments	$ 25,655	$ 36,370
Unpaid losses and loss adjustment expenses	27,422	20,256
Unearned premiums	27,251	19,183
State operating loss carryforwards	6,012	5,351
Stock compensation	2,155	1,521
Allowance for credit losses	2,810	1,694
Other	2,394	474
Deferred tax assets before allowance	93,699	84,849
Less: valuation allowance	(6,182)	(5,188)
Total deferred tax assets	87,517	79,661
Deferred tax liabilities [Abstract]
Unrealized gains on equity securities	8,667	5,459
Deferred policy acquisition costs, net of ceding commissions	18,563	12,935
Property and equipment	3,005	2,670
Other	1,583	1,614
Total deferred tax liabilities	31,818	22,678
Deferred income tax asset, net	55,699	56,983
State Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 126,800	$ 112,900

Reserves for unpaid losses an_3

Reserves for unpaid losses and loss adjustment expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reconciliation of consolidated beginning and ending reserves for unpaid losses and loss adjustment expenses [Roll Forward]
Gross reserves for unpaid losses and loss adjustment expenses, beginning of year	$ 1,692,875	$ 1,238,402	$ 881,344	$ 636,013
Allowance for credit losses - reinsurance recoverables	459
Net reserves for unpaid losses and loss adjustment expenses, beginning of period	1,061,363	763,783	552,283
Incurred losses and loss adjustment expenses [Abstract]
Current year	635,993	493,800	356,401
Prior year losses and loss adjustment expense	(35,774)	(35,887)	(31,986)
Total net losses and loss adjustment expenses incurred	600,219	457,913	324,415
Payments [Abstract]
Current year	38,565	49,205	23,765
Prior years	171,499	111,128	89,150
Total payments	210,064	160,333	112,915
Net reserves for unpaid losses and loss adjustment expenses, end of period	1,451,518	1,061,363	763,783
Reinsurance recoverable for unpaid Claims losses, net, ending balance	241,357	177,039	117,561
Gross reserves for unpaid losses and loss adjustment expenses, end of year	$ 1,692,875	$ 1,238,402	$ 881,344

Reserves for unpaid losses an_4

Reserves for unpaid losses and loss adjustment expenses Liability for Unpaid Losses and Loss Adjustment Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior Year Claims and Claims Adjustment Expense	$ (35,774)	$ (35,887)	$ (31,986)
Current year	635,993	493,800	356,401
Catastrophe [Member]
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Current year		26,600	8,600
Accident Year 2020 [Member]
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior Year Claims and Claims Adjustment Expense			(33,700)
Accident Year 2019 [Member]
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior Year Claims and Claims Adjustment Expense			$ 3,800
Accident Years 2020 and 2021
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior Year Claims and Claims Adjustment Expense		$ (41,800)
Accident Years 2021 and 2022
Causes of Increase (Decrease) in Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Prior Year Claims and Claims Adjustment Expense	$ (49,000)

Reserves for unpaid losses an_5

Reserves for unpaid losses and loss adjustment expenses Reserve Development (Details)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Claims Development
Liability for claims and claim adjustment expense, net	$ 1,301,451,000
Property [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	144,802,000
All outstanding liabilities not separately presented, net of reinsurance	3,000
Liability for claims and claim adjustment expense, net	66,579,000
Incurred claims and claim adjustment expense, net	211,378,000
Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	123,915,000
All outstanding liabilities not separately presented, net of reinsurance	76,000
Liability for claims and claim adjustment expense, net	244,880,000
Incurred claims and claim adjustment expense, net	368,719,000
Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	437,090,000
All outstanding liabilities not separately presented, net of reinsurance	2,868,000
Liability for claims and claim adjustment expense, net	989,992,000
Incurred claims and claim adjustment expense, net	1,424,214,000
Accident Year 2014 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	9,691,000	$ 9,638,000	$ 9,628,000	$ 9,491,000	$ 9,415,000	$ 8,290,000	$ 6,385,000	$ 5,039,000	$ 1,865,000	$ 435,000
Incurred claims and claim adjustment expense, net	9,868,000	9,880,000	10,266,000	10,620,000	10,988,000	10,948,000	11,217,000	11,748,000	14,289,000	18,847,000
Total of IBNR liabilities plus expected development on reported claims	$ 177,000
Cumulative number of reported claims	273
Accident Year 2014 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 38,169,000	37,375,000	35,807,000	34,338,000	31,026,000	23,771,000	17,576,000	8,489,000	3,081,000	698,000
Incurred claims and claim adjustment expense, net	41,820,000	41,677,000	41,367,000	42,434,000	41,859,000	39,313,000	36,678,000	38,049,000	40,668,000	$ 47,805,000
Total of IBNR liabilities plus expected development on reported claims	$ 2,546,000
Cumulative number of reported claims	1,261
Accident Year 2015 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 12,474,000	12,463,000	12,142,000	11,522,000	11,372,000	9,238,000	7,563,000	4,496,000	217,000
Incurred claims and claim adjustment expense, net	12,759,000	13,066,000	13,414,000	13,548,000	13,942,000	13,583,000	14,896,000	16,777,000	18,883,000
Total of IBNR liabilities plus expected development on reported claims	$ 93,000
Cumulative number of reported claims	259
Accident Year 2015 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 49,147,000	47,106,000	44,161,000	41,724,000	37,690,000	28,385,000	12,685,000	3,161,000	941,000
Incurred claims and claim adjustment expense, net	55,259,000	54,637,000	54,090,000	54,090,000	54,697,000	52,100,000	49,122,000	51,739,000	$ 59,717,000
Total of IBNR liabilities plus expected development on reported claims	$ 4,062,000
Cumulative number of reported claims	1,913
Accident Year 2016 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 12,691,000	12,299,000	12,105,000	11,381,000	9,839,000	6,907,000	3,015,000	1,158,000
Incurred claims and claim adjustment expense, net	12,707,000	13,228,000	13,602,000	13,583,000	14,322,000	14,675,000	14,693,000	19,170,000
Total of IBNR liabilities plus expected development on reported claims	$ 16,000
Cumulative number of reported claims	311
Accident Year 2016 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 55,595,000	51,533,000	43,311,000	34,437,000	28,924,000	17,225,000	6,015,000	1,099,000
Incurred claims and claim adjustment expense, net	65,323,000	64,612,000	60,861,000	57,401,000	55,534,000	53,549,000	55,680,000	$ 61,440,000
Total of IBNR liabilities plus expected development on reported claims	$ 6,331,000
Cumulative number of reported claims	1,640
Accident Year 2017 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 12,335,000	12,235,000	11,357,000	10,484,000	8,252,000	4,897,000	340,000
Incurred claims and claim adjustment expense, net	13,471,000	13,698,000	14,989,000	15,794,000	16,120,000	17,097,000	18,116,000
Total of IBNR liabilities plus expected development on reported claims	$ 661,000
Cumulative number of reported claims	372
Accident Year 2017 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 61,108,000	52,069,000	46,025,000	37,736,000	22,407,000	9,352,000	1,581,000
Incurred claims and claim adjustment expense, net	76,715,000	69,911,000	71,117,000	70,641,000	68,985,000	67,151,000	$ 71,126,000
Total of IBNR liabilities plus expected development on reported claims	$ 10,589,000
Cumulative number of reported claims	2,141
Accident Year 2018 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 12,623,000	11,205,000	10,330,000	8,931,000	5,030,000	507,000
Incurred claims and claim adjustment expense, net	14,272,000	14,411,000	17,057,000	18,612,000	20,234,000	22,429,000
Total of IBNR liabilities plus expected development on reported claims	$ 1,346,000
Cumulative number of reported claims	465
Accident Year 2018 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 72,174,000	54,441,000	35,138,000	22,860,000	10,995,000	2,638,000
Incurred claims and claim adjustment expense, net	97,005,000	93,215,000	83,952,000	78,386,000	78,331,000	$ 86,157,000
Total of IBNR liabilities plus expected development on reported claims	$ 17,691,000
Cumulative number of reported claims	2,380
Accident Year 2019 [Member] | Property [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 15,223,000	14,511,000	13,996,000	12,581,000	9,852,000
Incurred claims and claim adjustment expense, net	15,357,000	16,748,000	15,572,000	13,909,000	14,914,000
Total of IBNR liabilities plus expected development on reported claims	$ 0
Cumulative number of reported claims	643
Accident Year 2019 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 15,406,000	14,476,000	10,123,000	6,005,000	2,487,000
Incurred claims and claim adjustment expense, net	21,788,000	24,489,000	26,426,000	29,056,000	34,693,000
Total of IBNR liabilities plus expected development on reported claims	$ 4,227,000
Cumulative number of reported claims	562
Accident Year 2019 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 69,384,000	46,478,000	30,518,000	16,687,000	3,944,000
Incurred claims and claim adjustment expense, net	115,681,000	107,480,000	108,138,000	109,994,000	$ 112,266,000
Total of IBNR liabilities plus expected development on reported claims	$ 35,995,000
Cumulative number of reported claims	2,370
Accident Year 2020 [Member] | Property [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 35,023,000	31,765,000	30,321,000	19,897,000
Incurred claims and claim adjustment expense, net	37,078,000	36,807,000	37,939,000	40,612,000
Total of IBNR liabilities plus expected development on reported claims	$ 214,000
Cumulative number of reported claims	2,309
Accident Year 2020 [Member] | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 18,589,000	12,551,000	7,446,000	1,002,000
Incurred claims and claim adjustment expense, net	33,667,000	38,287,000	44,641,000	55,630,000
Total of IBNR liabilities plus expected development on reported claims	$ 13,458,000
Cumulative number of reported claims	784
Accident Year 2020 [Member] | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 32,606,000	17,805,000	8,673,000	2,400,000
Incurred claims and claim adjustment expense, net	135,045,000	131,082,000	136,212,000	$ 154,619,000
Total of IBNR liabilities plus expected development on reported claims	$ 86,636,000
Cumulative number of reported claims	2,681
Accident Year 2021 | Property [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 27,324,000	21,257,000	14,268,000
Incurred claims and claim adjustment expense, net	29,750,000	33,518,000	36,531,000
Total of IBNR liabilities plus expected development on reported claims	$ 1,403,000
Cumulative number of reported claims	1,144
Accident Year 2021 | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 12,895,000	8,437,000	1,146,000
Incurred claims and claim adjustment expense, net	52,935,000	66,191,000	84,018,000
Total of IBNR liabilities plus expected development on reported claims	$ 36,436,000
Cumulative number of reported claims	1,077
Accident Year 2021 | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 31,494,000	12,944,000	3,205,000
Incurred claims and claim adjustment expense, net	193,722,000	190,879,000	$ 200,598,000
Total of IBNR liabilities plus expected development on reported claims	$ 144,372,000
Cumulative number of reported claims	2,827
Accident Year 2022 | Property [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 46,965,000	33,004,000
Incurred claims and claim adjustment expense, net	53,676,000	67,127,000
Total of IBNR liabilities plus expected development on reported claims	$ 4,744,000
Cumulative number of reported claims	2,330
Accident Year 2022 | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 12,381,000	3,052,000
Incurred claims and claim adjustment expense, net	81,394,000	101,064,000
Total of IBNR liabilities plus expected development on reported claims	$ 59,239,000
Cumulative number of reported claims	1,205
Accident Year 2022 | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 23,084,000	4,658,000
Incurred claims and claim adjustment expense, net	271,399,000	$ 272,692,000
Total of IBNR liabilities plus expected development on reported claims	$ 227,940,000
Cumulative number of reported claims	3,064
Accident Year 2023 | Property [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 20,267,000
Incurred claims and claim adjustment expense, net	75,517,000
Total of IBNR liabilities plus expected development on reported claims	$ 47,874,000
Cumulative number of reported claims	902
Accident Year 2023 | Casualty - claims made [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 4,830,000
Incurred claims and claim adjustment expense, net	115,858,000
Total of IBNR liabilities plus expected development on reported claims	$ 98,185,000
Cumulative number of reported claims	1,336
Accident Year 2023 | Casualty - occurrence [Member]
Claims Development
Cumulative paid claims and allocated claim adjustment expense, net	$ 4,329,000
Incurred claims and claim adjustment expense, net	372,245,000
Total of IBNR liabilities plus expected development on reported claims	$ 358,062,000
Cumulative number of reported claims	2,195

Reserves for unpaid losses an_6

Reserves for unpaid losses and loss adjustment expenses Historical Claims Duration (Details)	Dec. 31, 2023 Rate
Property [Member]
Historical Claims Duration [Line Items]
Historical Claims Duration, Year One	50.80%
Historical Claims Duration, Year Two	23.80%
Historical Claims Duration, Year Three	11.20%
Historical Claims Duration, Year Four	6.10%
Historical Claims Duration, Year Five	4.60%
Casualty - claims made [Member]
Historical Claims Duration [Line Items]
Historical Claims Duration, Year One	4.60%
Historical Claims Duration, Year Two	21%
Historical Claims Duration, Year Three	22.70%
Historical Claims Duration, Year Four	16.30%
Historical Claims Duration, Year Five	10.80%
Historical Claims Duration, Year Six	6.90%
Historical Claims Duration, Year Seven	2%
Historical Claims Duration, Year Eight	2.30%
Historical Claims Duration, Year Nine	0.10%
Historical Claims Duration, Year Ten	0.50%
Casualty - occurrence [Member]
Historical Claims Duration [Line Items]
Historical Claims Duration, Year One	2%
Historical Claims Duration, Year Two	7.10%
Historical Claims Duration, Year Three	13.10%
Historical Claims Duration, Year Four	17.90%
Historical Claims Duration, Year Five	15.10%
Historical Claims Duration, Year Six	12.90%
Historical Claims Duration, Year Seven	9.20%
Historical Claims Duration, Year Eight	5%
Historical Claims Duration, Year Nine	3.70%
Historical Claims Duration, Year Ten	1.90%

Reserves for unpaid losses an_7

Reserves for unpaid losses and loss adjustment expenses Reconciliation of Claims Development to Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Liability for claims and claim adjustment expense, net	$ 1,301,451
Reinsurance recoverable for unpaid losses	241,357	$ 177,039	$ 117,561	$ 83,730
Reinsurance Recoverable, Allowance for Credit Loss	(744)	$ (459)
Unallocated claim adjustment expenses	149,323
Property [Member]
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Liability for claims and claim adjustment expense, net	66,579
Reinsurance recoverable for unpaid losses	60,888
Casualty - claims made [Member]
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Liability for claims and claim adjustment expense, net	244,880
Reinsurance recoverable for unpaid losses	21,393
Casualty - occurrence [Member]
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Liability for claims and claim adjustment expense, net	989,992
Reinsurance recoverable for unpaid losses	$ 159,820

Reinsurance, Effects of Reinsur

Reinsurance, Effects of Reinsurance on Premiums Written and Earned (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Written [Abstract]
Direct	$ 1,568,815	$ 1,102,092	$ 764,373
Ceded	(304,185)	(165,282)	(104,164)
Net written premiums	1,264,630	936,810	660,209
Earned [Abstract]
Direct	1,367,141	950,145	677,630
Ceded	(294,604)	(156,026)	(94,751)
Net earned premiums	1,072,537	794,119	582,879
Ceded incurred losses and loss adjustment expenses	$ 115,900	$ 117,900	$ 49,700

Reinsurance Reinsurance Balance

Reinsurance Reinsurance Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reinsurance Disclosure [Abstract]
Reinsurance recoverables on paid losses, gross	$ 6,479	$ 43,415
Reinsurance recoverable for unpaid losses	241,357	177,039	$ 117,561	$ 83,730
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	247,836	220,454
Reinsurance Recoverable, Allowance for Credit Loss	744	459
Concentration Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	247,836	220,454
Ceded unearned premiums	52,516	$ 42,935
Credit Risk Reinsurer One [Member]
Reinsurance Disclosure [Abstract]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	64,100
Concentration Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	64,100
Ceded unearned premiums	11,900
Credit Risk Reinsurer Two [Member]
Reinsurance Disclosure [Abstract]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	31,000
Concentration Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	31,000
Ceded unearned premiums	6,100
Credit Risk Reinsurer Three [Member]
Reinsurance Disclosure [Abstract]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	27,300
Concentration Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	27,300
Ceded unearned premiums	5,500
Credit Risk Reinsurer Four [Member]
Reinsurance Disclosure [Abstract]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	23,400
Concentration Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	23,400
Ceded unearned premiums	5,400
Credit Risk Reinsurer Five [Member]
Reinsurance Disclosure [Abstract]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	17,700
Concentration Risk [Line Items]
Reinsurance recoverables, net of allowance for credit losses of $744 in 2023 and $459 in 2022	17,700
Ceded unearned premiums	$ 4,900
Prepaid reinsurance premiums ceded to five reinsurers as a percentage of total ceded unearned premium balance [Member] | Major Reinsurers [Member] | Reinsurer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	64.40%
Reinsurance recoverables on paid and unpaid losses from the Company’s five largest reinsurers as percent of total reinsurance recoverables [Member] | Major Reinsurers [Member] | Reinsurer Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	66%

Stockholders' Equity Capital St

Stockholders' Equity Capital Stock (Details) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Equity, Attributable to Parent [Abstract]
Preferred stock, shares issued	0	0
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	100,000,000	100,000,000
Preferred stock, outstanding (in shares)	0	0
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01

Stockholders' Equity, Public Of

Stockholders' Equity, Public Offering (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 15, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Equity, Attributable to Parent [Abstract]
Stock issued, shares	155,000		155,000
Share price (in dollars per share)	$ 308.30
Net proceeds from public offering, net of discounts, commissions and other offering costs	$ 47,500	$ 0	$ 47,498	$ 0

Stockholders' Equity, Equity-ba

Stockholders' Equity, Equity-based Compensation, Options (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jul. 27, 2016	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation		$ 9,400	$ 6,700	$ 4,800
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Intrinsic value of options exercised		$ 17,700	$ 15,600
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term of option granted	10 years
Award vesting period	4 years
Granted (in dollars per share)	$ 2.71
Options outstanding, number of awards [Roll Forward]
Options, beginning of the year (in shares)		256,357
Granted, shares		0
Forfeited (in shares)		0
Exercised (in shares)		(54,797)
Options, end of year (in shares)		201,560	256,357
Exercisable, shares		201,560
Options outstanding, weighted average exercise price [Abstract]
Options beginning of the year (in dollars per share)		$ 16
Granted	$ 16	0
Forfeited		0
Exercised		16
Options end of the year (in dollars per share)		16	$ 16
Exercisable		$ 16
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding, weighted average remaining contractual term		2 years 7 months 6 days
Exercisable, weighted average remaining contractual term		2 years 7 months 6 days
Outstanding, aggregate intrinsic value		$ 64,280
Exercisable, aggregate intrinsic value		$ 64,280
2016 Omnibus Incentive Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance	2,073,832
2016 Omnibus Incentive Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	1,036,916

Stockholders' Equity - Equity-b

Stockholders' Equity - Equity-based Compensation, Restricted Stock (Details) - Restricted Stock [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares withheld for taxes	13,556
Vested in period, fair value	$ 12.8	$ 10	$ 6.8
Nonvested Restricted Stock, Number of Shares [Roll Forward]
Nonvested outstanding at the beginning of the period, shares		98,621
Granted, shares	51,176
Vested, shares	(40,951)
Forfeited, shares	(1,024)
Nonvested outstanding at the end of the period, shares	107,822
Nonvested Restricted Stock, Weighted Average Grant Date Fair Value [Abstract]
Nonvested outstanding at the beginning of the period	$ 182.37
Granted	313.35	$ 211.86	$ 185
Vested	163.98
Forfeited	252.44
Nonvested outstanding at the end of the period	$ 250.86	$ 182.37
Unrecognized stock-based compensation expense	$ 19.2
Compensation cost not yet recognized, period	2 years 3 months 18 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Period	4 years

Stockholders' Equity - Subseque

Stockholders' Equity - Subsequent Event (Details) - $ / shares			12 Months Ended
	Feb. 12, 2024	Jan. 01, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Subsequent Event [Member] | Dividend Declared [Member]
Subsequent Event [Line Items]
Dividend declared date	Feb. 12, 2024
Dividends payable, per share	$ 0.15
Dividend payable date	Mar. 13, 2024
Dividend record date	Feb. 27, 2024
Restricted Stock [Member]
Subsequent Event [Line Items]
Grant date fair value			$ 313.35	$ 211.86	$ 185
Restricted Stock [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Granted		3,576
Grant date fair value		$ 334.91

Earnings per share (Details)

Earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reconciliation of numerator and denominator of the basic and diluted earnings per share computations [Abstract]
Net income	$ 308,093	$ 159,114	$ 152,659
Basic earnings per share [Abstract]
Earnings per share - basic	$ 13.37	$ 6.97	$ 6.73
Diluted earnings per share [Abstract]
Earnings per share - diluted	$ 13.22	$ 6.88	$ 6.62
Basic weighted average shares outstanding [Abstract]
Weighted average shares outstanding - basic	23,045,000	22,815,000	22,693,000
Dilutive effect of shares issued under stock compensation arrangements [Abstract]
Dilutive effect of shares issued under stock compensation arrangements (in shares)	262,000	310,000	369,000
Diluted weighted average shares outstanding [Abstract]
Weighted average shares outstanding - diluted (in shares)	23,307,000	23,125,000	23,062,000
Antidilutive securities (in shares)	1,000	0	30,000
Stock options [Member]
Dilutive effect of shares issued under stock compensation arrangements [Abstract]
Dilutive effect of shares issued under stock compensation arrangements (in shares)	214,000	269,000	324,000
Restricted Stock [Member]
Dilutive effect of shares issued under stock compensation arrangements [Abstract]
Dilutive effect of shares issued under stock compensation arrangements (in shares)	48,000	41,000	45,000

Debt (Details)

Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Repayments of Long-Term Lines of Credit	$ 62,000	$ 43,000	$ 0
Lines of Credit, Maximum Borrowing Capacity under former agreement	50,000
Proceeds from Lines of Credit	0	73,000	0
Interest Paid, Excluding Capitalized Interest, Operating Activities	10,500	2,400	$ 900
Debt Issuance Costs, Net	(2,154)	(2,253)
Long-Term Debt	183,846	195,747
Amended debt instrument borrowing capacity	200,000
Senior Notes
Debt Instrument [Line Items]
Debt instrument borrowing capacity	$ 150,000
Line of Credit
Debt Instrument [Line Items]
Maturity date	Jul. 22, 2027
Accordion feature	$ 30,000
Line of Credit Facility, Commitment Fee Percentage	0.25%
Credit facility	$ 11,000	73,000
Interest rate description	The loans under the Amended and Restated Credit Agreement bear interest, at the Company's option, at a rate equal to the Adjusted Term SOFR Rate (as defined therein) plus 1.625% or the Alternate Base Rate (as defined therein) plus 0.625%.
Current borrowing capacity	$ 100,000
Weighted average interest rate	6.84%
2034 Series A Notes | Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	Jul. 22, 2022
Debt Instrument, Face Amount	$ 125,000	125,000
Debt Instrument, Interest Rate, Stated Percentage	5.15%
Debt Instrument, Maturity Date	Jul. 22, 2034
Debt Instrument, Date of First Required Payment	Jul. 22, 2030
Debt Instrument, Periodic Payment, Principal	$ 25,000
2034 Series B Notes | Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Issuance Date	Sep. 18, 2023
Debt Instrument, Face Amount	$ 50,000	$ 0
Debt Instrument, Interest Rate, Stated Percentage	6.21%
Debt Instrument, Maturity Date	Jul. 22, 2034
Debt Instrument, Date of First Required Payment	Jul. 22, 2030
Debt Instrument, Periodic Payment, Principal	$ 10,000

Employee benefit plan (Details)

Employee benefit plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Expenses related to employee benefit plan	$ 3.8	$ 3.1	$ 2.2

Other comprehensive income (l_3

Other comprehensive income (loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Unrealized gains (losses) arising during the period, before income taxes	$ 49,384	$ (193,970)	$ (26,792)
Income taxes	(10,371)	40,734	5,626
Unrealized gains (losses) arising during the period, net of income tax	39,013	(153,236)	(21,166)
Less reclassification adjustment [Abstract]
Net realized investment gains	(1,443)	121	2,644
Income taxes	303	(25)	(555)
Reclassification adjustment included in net income	(1,140)	96	2,089
Allowance for Credit losses expense, before Tax	(187)	(366)	0
Income taxes	39	77	0
Reclassification adjustment included in net income	(148)	(289)	0
Other comprehensive income (loss)	$ 40,301	$ (153,043)	$ (23,255)

Underwriting information (Detai

Underwriting information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Rate	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Revenue from External Customer [Line Items]
Gross written premiums	$ 1,568,815	$ 1,102,092	$ 764,373
Number of operating segments	1
Commercial Property [Member]
Revenue from External Customer [Line Items]
Gross written premiums	$ 411,956	181,505	72,392
Excess Casualty [Member]
Revenue from External Customer [Line Items]
Gross written premiums	194,049	147,485	108,487
Small Business [Member]
Revenue from External Customer [Line Items]
Gross written premiums	174,080	149,366	112,553
Construction [Member]
Revenue from External Customer [Line Items]
Gross written premiums	137,887	122,524	101,441
Allied Health [Member]
Revenue from External Customer [Line Items]
Gross written premiums	67,808	58,839	51,945
Products Liability [Member]
Revenue from External Customer [Line Items]
Gross written premiums	61,786	60,374	55,070
Life Sciences [Member]
Revenue from External Customer [Line Items]
Gross written premiums	41,379	41,346	40,487
General Casualty [Member]
Revenue from External Customer [Line Items]
Gross written premiums	118,745	69,784	36,037
Management Liability [Member]
Revenue from External Customer [Line Items]
Gross written premiums	26,617	28,856	28,031
Energy [Member]
Revenue from External Customer [Line Items]
Gross written premiums	38,637	32,217	19,710
Environmental [Member]
Revenue from External Customer [Line Items]
Gross written premiums	25,938	19,455	13,584
Entertainment
Revenue from External Customer [Line Items]
Gross written premiums	39,218	22,268	12,401
Health Care [Member]
Revenue from External Customer [Line Items]
Gross written premiums	20,378	16,916	11,156
Inland Marine [Member]
Revenue from External Customer [Line Items]
Gross written premiums	18,669	14,396	9,752
Public Entity [Member]
Revenue from External Customer [Line Items]
Gross written premiums	20,028	15,512	9,977
Personal Insurance [Member]
Revenue from External Customer [Line Items]
Gross written premiums	24,182	31,289	27,002
Small Property
Revenue from External Customer [Line Items]
Gross written premiums	43,893	21,002	6,160
Commercial Auto
Revenue from External Customer [Line Items]
Gross written premiums	19,050	5,950	977
Aviation
Revenue from External Customer [Line Items]
Gross written premiums	6,453	4,424	2,099
Product Recall
Revenue from External Customer [Line Items]
Gross written premiums	1,637	1,419	810
Ocean Marine
Revenue from External Customer [Line Items]
Gross written premiums	2,339	765	215
Railroad
Revenue from External Customer [Line Items]
Gross written premiums	15	0	0
Excess Professional
Revenue from External Customer [Line Items]
Gross written premiums	24,033	22,826	21,340
High Value Homeowners
Revenue from External Customer [Line Items]
Gross written premiums	14,295	3,261	121
Commercial [Member]
Revenue from External Customer [Line Items]
Gross written premiums	1,530,338	1,067,542	737,250
Personal [Member]
Revenue from External Customer [Line Items]
Gross written premiums	38,477	34,550	27,123
Professional Liability Insurance
Revenue from External Customer [Line Items]
Gross written premiums	$ 35,743	$ 30,313	$ 22,626
Revenue Benchmark [Member]
Revenue from External Customer [Line Items]
Number of insurance brokers	3
Insurance brokers greater than 10% of gross written premium	0
Major Insurance Brokers, Group One [Member] | Revenue Benchmark [Member]
Revenue from External Customer [Line Items]
Gross written premiums	$ 316,500
Major Insurance Brokers, Group One [Member] | Revenue Benchmark [Member] | Customer Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk, percentage | Rate	20.20%
Major Insurance Brokers, Group Two [Member] | Revenue Benchmark [Member]
Revenue from External Customer [Line Items]
Gross written premiums	$ 286,800
Major Insurance Brokers, Group Two [Member] | Revenue Benchmark [Member] | Customer Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk, percentage | Rate	18.30%
Major Insurance Brokers, Group Three [Member] | Revenue Benchmark [Member]
Revenue from External Customer [Line Items]
Gross written premiums	$ 178,700
Major Insurance Brokers, Group Three [Member] | Revenue Benchmark [Member] | Customer Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk, percentage | Rate	11.40%

Statutory financial informati_3

Statutory financial information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments [Abstract]
Statutory net income	$ 259,042	$ 151,105	$ 115,885
Statutory capital and surplus	$ 1,167,382	$ 835,664	$ 606,910
Percentage of policyholder surplus as of end of prior year used in determining maximum dividend distribution	10%
Maximum dividend distribution that can be paid without prior approval	$ 257,300

Schedule I-Summary of Investmen

Schedule I-Summary of Investments-Other than Related Parties (Details) $ in Thousands	Dec. 31, 2023 USD ($)
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	$ 3,048,398
Amount	2,966,952
Fixed Maturities [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	2,834,463
Fair Value	2,711,759
Amount	2,711,759
US Treasury and Government [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	28,003
Fair Value	27,254
Amount	27,254
US States and Political Subdivisions Debt Securities [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	191,080
Fair Value	171,044
Amount	171,044
Debt Security, Corporate, US [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	1,437,468
Fair Value	1,387,693
Amount	1,387,693
Asset-backed Securities [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	641,700
Fair Value	641,760
Amount	641,760
Residential Mortgage Backed Securities [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	463,904
Fair Value	417,106
Amount	417,106
Commercial mortgage-backed aecurities [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	72,308
Fair Value	66,902
Amount	66,902
Equity Securities, Investment Summary [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	193,543
Fair Value	234,813
Amount	234,813
Exchange Traded Funds [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	65,401
Fair Value	106,300
Amount	106,300
Banks, Trust and Insurance, Equities
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	22,090
Fair Value	24,528
Amount	24,528
Industrial, Miscellaneous, and All Others
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	67,763
Fair Value	70,812
Amount	70,812
Nonredeemable Preferred Stock [Member]
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	38,289
Fair Value	33,173
Amount	33,173
Short-Term Investments
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items]
Cost	5,601
Fair Value	5,589
Amount	$ 5,589

Schedule II - Condensed Finan_3

Schedule II - Condensed Financial Information of Registrant, Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Assets
Deferred income tax asset, net	$ 55,699	$ 56,983
Other assets	66,443	54,844
Total assets	3,772,974	2,747,122
Liabilities:
Accounts payable and accrued expenses	44,922	31,361
Long-Term Debt	183,846	195,747
Other liabilities	15,566	4,462
Total liabilities	2,686,142	2,001,673
Stockholders' Equity [Abstract]
Common stock	232	231
Additional paid-in capital	352,970	347,015
Retained earnings	828,247	533,121
Accumulated other comprehensive loss	(94,617)	(134,918)
Stockholders' equity	1,086,832	745,449	$ 699,335	$ 576,238
Total liabilities and stockholders' equity	3,772,974	2,747,122
Parent Company [Member]
Assets
Cash and cash equivalents	17,082	34,789	$ 14,596	$ 8,395
Investment in subsidiaries	1,230,371	827,911
Deferred income tax asset, net	1,673	1,301
Other assets	410	278
Total assets	1,276,015	945,784
Liabilities:
Accounts payable and accrued expenses	2,042	1,558
Income tax payable	3,201	2,948
Long-Term Debt	183,846	195,747
Other liabilities	94	82
Total liabilities	189,183	200,335
Stockholders' Equity [Abstract]
Common stock	232	231
Additional paid-in capital	352,970	347,015
Retained earnings	828,247	533,121
Accumulated other comprehensive loss	(94,617)	(134,918)
Stockholders' equity	1,086,832	745,449
Total liabilities and stockholders' equity	1,276,015	945,784
Parent Company [Member] | Related Party
Assets
Due from subsidiaries	$ 26,479	$ 81,505

Schedule II - Condensed Finan_4

Schedule II - Condensed Financial Information of Registrant, Statements of Income and Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Revenues	$ 1,224,449	$ 838,804	$ 653,472
Net investment income	102,335	51,282	31,048
Expenses [Abstract]
Other expenses	942	721	669
Total expenses	840,432	643,240	464,671
Income tax benefit	75,924	36,450	36,142
Net income	308,093	159,114	152,659
Other Comprehensive Income (Loss) [Abstract]
Comprehensive income	348,394	6,071	129,404
Interest expense	10,301	4,284	994
Parent Company [Member]
Revenues:
Revenues	11,918	8,815	7,002
Net investment income	0	121	0
Realized Investment Gains (Losses)	0	8	0
Expenses [Abstract]
Other operating expenses	13,007	9,765	7,972
Total expenses	23,308	14,049	8,966
Loss before equity in net income of subsidiaries	(11,390)	(5,234)	(1,964)
Income tax benefit	(7,324)	(5,387)	(3,424)
Income before equity in net income of subsidiaries	(4,066)	153	1,460
Equity in net income of subsidiaries	312,159	158,961	151,199
Net income	308,093	159,114	152,659
Other Comprehensive Income (Loss) [Abstract]
Equity in other comprehensive earnings (losses) of subsidiaries	40,301	(153,043)	(23,255)
Comprehensive income	348,394	6,071	129,404
Interest expense	10,301	4,284	$ 994
Parent Company [Member] | Related Party
Revenues:
Revenues	$ 11,918	$ 8,686

Schedule II - Condensed Finan_5

Schedule II - Condensed Financial Information of Registrant, Statements of Cash Flows (Details) - USD ($) $ in Thousands		12 Months Ended
	Nov. 15, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities:
Net income		$ 308,093	$ 159,114	$ 152,659
Adjustments to reconcile net income to net cash used in operating activities:
Deferred tax (benefit) expense		(9,429)	(14,191)	(576)
Stock compensation expense		9,361	6,678	4,844
Dividends received from subsidiary		0	0	8,000
Net cash provided by operating activities		859,835	557,815	407,042
Net Cash Provided by (Used in) Investing Activities [Abstract]
Net cash provided by (used in) investing activities		(860,892)	(708,573)	(351,955)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	$ 47,500	0	47,498	0
Proceeds from Lines of Credit		0	73,000	0
Dividends paid		(12,954)	(11,927)	(10,021)
Proceeds from Issuance of Long-Term Debt		50,000	125,000	0
Repayments of Long-Term Lines of Credit		(62,000)	(43,000)	0
Debt issuance costs		(164)	(2,381)	0
Payroll taxes withheld and remitted on share-based payments		(4,282)	(3,288)	(2,101)
Common stock issued, stock options exercised		877	1,090	982
Net cash provided by (used in) financing activities		(28,523)	185,992	(11,140)
Net change in cash and cash equivalents		(29,580)	35,234	43,947
Parent Company [Member]
Operating activities:
Net income		308,093	159,114	152,659
Adjustments to reconcile net income to net cash used in operating activities:
Deferred tax (benefit) expense		(372)	(367)	(347)
Stock compensation expense		9,361	6,678	4,844
Equity in undistributed earnings of subsidiaries		(312,159)	(158,961)	(151,199)
Changes in operating assets and liabilities		55,893	(71,639)	3,955
Dividends received from subsidiary		0	0	8,000
Net cash provided by operating activities		60,816	(65,175)	17,912
Net Cash Provided by (Used in) Investing Activities [Abstract]
Contribution to subsidiary		(50,000)	(100,624)	(571)
Net cash provided by (used in) investing activities		(50,000)	(100,624)	(571)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs		0	47,498	0
Proceeds from Lines of Credit		0	73,000	0
Dividends paid		(12,954)	(11,927)	(10,021)
Proceeds from Issuance of Long-Term Debt		50,000	125,000	0
Repayments of Long-Term Lines of Credit		(62,000)	(43,000)	0
Debt issuance costs		(164)	(2,381)	0
Payroll taxes withheld and remitted on share-based payments		(4,282)	(3,288)	(2,101)
Common stock issued, stock options exercised		877	1,090	982
Net cash provided by (used in) financing activities		(28,523)	185,992	(11,140)
Net change in cash and cash equivalents		(17,707)	20,193	6,201
Cash and cash equivalents at beginning of period		34,789	14,596	8,395
Cash and cash equivalents at end of period		$ 17,082	$ 34,789	$ 14,596

Schedule II - Condensed Finan_6

Schedule II - Condensed Financial Information of Registrant, Notes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Condensed Financial Information Disclosure [Abstract]
Interest expense	$ 10,301	$ 4,284	$ 994
Interest Paid, Excluding Capitalized Interest, Operating Activities	10,500	2,400	900
Cash dividends paid to parent company by consolidated subsidiaries	0	0	8,000
Amended debt instrument borrowing capacity	200,000
Lines of Credit, Maximum Borrowing Capacity under former agreement	50,000
Repayments of Long-Term Lines of Credit	$ (62,000)	$ (43,000)	$ 0

Schedule V - Valuation and Qu_2

Schedule V - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for Premiums Receivable [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 8,067	$ 3,391	$ 3,087
Additions amounts charged to expense	9,790	5,988	2,189
Deductions amounts written off or disposals	(4,474)	(1,312)	(1,885)
Balance at end of period	13,383	8,067	3,391
Valuation Allowance for Deferred Tax Assets [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	5,188	4,159	3,491
Additions amounts charged to expense	994	1,029	668
Deductions amounts written off or disposals	0	0	0
Balance at end of period	6,182	5,188	4,159
Allowance for Reinsurance Recoverable [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	459	400	282
Additions amounts charged to expense	285	59	118
Deductions amounts written off or disposals	0	0	0
Balance at end of period	744	459	400
SEC schedule, 12-09 Allowance Fixed-Maturity Securities
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	366	0
Additions amounts charged to expense	199	366
Deductions amounts written off or disposals	(12)	0
Balance at end of period	$ 553	$ 366	$ 0

Accounting Changes and Error _2

Accounting Changes and Error Corrections (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Insurance Fee Income	$ 27,026	$ 19,604	$ 13,693
Error Corrections and Prior Period Adjustments, Description	The Company charges insureds certain policy fees and recognizes such fees into earnings when the related premium is written. Previously, the Company presented these fees as a reduction of underwriting, acquisition and insurance expenses. Effective April 1, 2023, the Company corrected its accounting policy to present these fees as fee income in the consolidated statements of income and comprehensive income in accordance with ASC 944, Financial Services–Insurance. The Company presented $27.0 million as fee income for the year ended December 31, 2023 in the consolidated statements of income and comprehensive income. The Company reclassified $19.6 million and $13.7 million to fee income from underwriting, acquisition and insurance expenses in the previously issued financial statements on Form 10-K for the years ended December 31, 2022 and 2021, respectively, to correct prior periods’ presentation. The Company considered the qualitative and quantitative impacts and determined that the correction was not material to the Company's previously issued consolidated financial statements.
Revision of Prior Period, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Insurance Fee Income		$ 19,600	$ 13,700