RLI (RLI) 10-K 18 Feb 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Feb. 02, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2021
Entity File Number	001-09463
Entity Registrant Name	RLI CORP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	37-0889946
Entity Address, Address Line One	9025 North Lindbergh Drive
Entity Address, City or Town	Peoria
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	61615
City Area Code	309
Local Phone Number	692-1000
Title of 12(b) Security	Common Stock $0.01 par value
Trading Symbol	RLI
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 4,592,962,657
Entity Common Stock, Shares Outstanding		45,289,337
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Central Index Key	0000084246
Amendment Flag	false
ICFR Auditor Attestation Flag	true
Auditor Name	Deloitte & Touche LLP
Auditor Location	Chicago, Illinois
Auditor Firm ID	34
Documents Incorporated by Reference	Portions of the Registrant’s definitive Proxy Statement for the 2022 annual meeting of shareholders are incorporated herein by reference into Part III of this document.

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
ASSETS
Available-for-sale, at fair value (amortized cost of $2,346,267 and allowance for credit losses of $441 in 2021) (amortized cost of $2,061,467 and allowance for credit losses of $397 in 2020)	$ 2,409,887	$ 2,196,626
Equity securities, at fair value (cost - $324,501 in 2021 and $293,190 in 2020)	613,776	524,006
Other invested assets	50,501	54,232
Cash	88,804	62,217
Total investments and cash	3,162,968	2,837,081
Accrued investment income	17,505	16,126
Premiums and reinsurance balances receivable, net of allowances for uncollectible amounts of $18,067 in 2021 and $17,658 in 2020	167,279	174,628
Ceded unearned premiums	130,916	113,488
Reinsurance balances recoverable on unpaid losses and settlement expenses, net of allowances for uncollectible amounts of $11,188 in 2021 and $8,634 in 2020	608,086	443,729
Deferred policy acquisition costs	103,553	88,425
Property and equipment, at cost, net of accumulated depreciation of $75,236 in 2021 and $68,682 in 2020	52,161	51,406
Investment in unconsolidated investees	171,311	128,382
Goodwill and intangibles	53,562	53,719
Other assets	40,961	31,501
TOTAL ASSETS	4,508,302	3,938,485
LIABILITIES
Unpaid losses and settlement expenses	2,043,555	1,750,049
Unearned premiums	680,444	586,386
Reinsurance balances payable	42,851	42,265
Funds held	89,773	81,747
Income taxes - deferred	83,509	80,235
Long-term debt	199,676	149,489
Accrued expenses	98,274	75,925
Other liabilities	40,859	36,411
TOTAL LIABILITIES	3,278,941	2,802,507
SHAREHOLDERS' EQUITY
Common stock ($0.01 par value) (Shares authorized - 200,000,000) (68,219,551 shares issued and 45,289,337 shares outstanding in 2021) (68,072,794 shares issued and 45,142,580 shares outstanding in 2020)	682	681
Paid-in capital	343,742	335,365
Accumulated other comprehensive earnings	49,826	108,714
Retained earnings	1,228,110	1,084,217
Deferred compensation	9,642	8,292
Treasury stock, at cost (22,930,214 shares in 2021 and 2020)	(402,641)	(401,291)
TOTAL SHAREHOLDERS' EQUITY	1,229,361	1,135,978
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 4,508,302	$ 3,938,485

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Available-for-sale, amortized cost	$ 2,346,267	$ 2,061,467
Available-for-sale, allowance for credit losses	441	397
Equity securities, cost	324,501	293,190
Premiums and reinsurance balances receivable, allowances for uncollectible amounts	18,067	17,658
Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts	11,188	8,634
Property and equipment, accumulated depreciation	$ 75,236	$ 68,682
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	68,219,551	68,072,794
Common stock, shares outstanding (in shares)	45,289,337	45,142,580
Treasury stock, shares (in shares)	22,930,214	22,930,214

Consolidated Statements of Earn

Consolidated Statements of Earnings and Comprehensive Earnings - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Net premiums earned	$ 980,903	$ 865,747	$ 839,111
Net investment income	68,862	67,893	68,870
Net realized gains	64,222	17,885	17,520
Net unrealized gains on equity securities	65,258	32,101	78,090
Consolidated revenue	1,179,245	983,626	1,003,591
Losses and settlement expenses	456,602	442,884	413,416
Policy acquisition costs	317,468	286,438	288,697
Insurance operating expenses	76,907	66,828	69,430
Interest expense on debt	7,677	7,603	7,588
General corporate expenses	13,330	10,265	12,686
Total expenses	871,984	814,018	791,817
Equity in earnings of unconsolidated investees	37,060	20,233	20,960
Earnings before income taxes	344,321	189,841	232,734
Income tax expense:
Current	46,040	24,174	26,426
Deferred	18,927	8,576	14,666
Income tax expense	64,967	32,750	41,092
Net earnings	279,354	157,091	191,642
Other comprehensive earnings (loss), net of tax	(58,888)	56,219	67,045
Comprehensive earnings	$ 220,466	$ 213,310	$ 258,687
Basic net earnings per share	$ 6.18	$ 3.49	$ 4.28
Diluted net earnings per share	$ 6.11	$ 3.46	$ 4.23
Weighted average number of common shares outstanding:
Basic	45,230	45,000	44,734
Diluted	45,712	45,376	45,257

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common stock	Paid-in Capital	Accumulated Other Comprehensive Earnings (Loss)	Accumulated Other Comprehensive Earnings (Loss)Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings	Retained EarningsCumulative Effect, Period of Adoption, Adjustment	Deferred Compensation	Treasury Stock at Cost
Stockholders' Equity Attributable to Parent, Beginning Balance at Dec. 31, 2018	$ 806,842		$ 674	$ 305,660	$ (14,572)		$ 908,079		$ 8,354	$ (401,353)
Shares, Outstanding, Beginning Balance at Dec. 31, 2018			44,504,043
Increase Decrease In Stockholders Equity Roll Forward
Net earnings	191,642						191,642
Other comprehensive earnings (loss), net of tax	67,045				67,045
Deferred compensation									(374)	374
Share-based compensation	15,534		$ 4	15,530
Share-based compensation (in shares)			364,972
Dividends and dividend equivalents	(85,675)						(85,675)
Stockholders' Equity Attributable to Parent, Ending Balance at Dec. 31, 2019	$ 995,388	$ 1,095	$ 678	321,190	52,473	$ 22	1,014,046	$ 1,073	7,980	(400,979)
Shares, Outstanding, Ending Balance at Dec. 31, 2019			44,869,015
Accounting Standards Update [Extensible List]	ASU 2016-13
Increase Decrease In Stockholders Equity Roll Forward
Net earnings	$ 157,091						157,091
Other comprehensive earnings (loss), net of tax	56,219				56,219
Deferred compensation									312	(312)
Share-based compensation	14,178		$ 3	14,175
Share-based compensation (in shares)			273,565
Dividends and dividend equivalents	(87,993)						(87,993)
Stockholders' Equity Attributable to Parent, Ending Balance at Dec. 31, 2020	1,135,978		$ 681	335,365	108,714		1,084,217		8,292	(401,291)
Shares, Outstanding, Ending Balance at Dec. 31, 2020			45,142,580
Increase Decrease In Stockholders Equity Roll Forward
Net earnings	279,354						279,354
Other comprehensive earnings (loss), net of tax	(58,888)				(58,888)
Deferred compensation									1,350	(1,350)
Share-based compensation	8,378		$ 1	8,377
Share-based compensation (in shares)			146,757
Dividends and dividend equivalents	(135,461)						(135,461)
Stockholders' Equity Attributable to Parent, Ending Balance at Dec. 31, 2021	$ 1,229,361		$ 682	$ 343,742	$ 49,826		$ 1,228,110		$ 9,642	$ (402,641)
Shares, Outstanding, Ending Balance at Dec. 31, 2021			45,289,337

Consolidated Statements of Sh_2

Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement Of Stockholders Equity [Abstract]
Cash dividends paid per common share	$ 2.99	$ 1.95	$ 1.91

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net earnings	$ 279,354	$ 157,091	$ 191,642
Adjustments to reconcile net earnings to net cash provided by operating activities:
Net realized gains	(64,222)	(17,885)	(17,520)
Net unrealized gains on equity securities	(65,258)	(32,101)	(78,090)
Depreciation	7,394	7,432	8,164
Deferred income tax expense	18,927	8,576	14,666
Other items, net	14,141	10,460	25,341
Change in:
Accrued investment income	(1,379)	(1,539)	(552)
Premiums and reinsurance balances receivable (net of direct write-offs and commutations)	7,349	(14,259)	(7,793)
Reinsurance balances payable	586	16,574	3,100
Funds held	8,026	(1,611)	11,049
Ceded unearned premiums	(17,428)	(19,832)	(22,482)
Reinsurance balances recoverable on unpaid losses and settlement expenses	(164,357)	(59,212)	(19,518)
Deferred policy acquisition costs	(15,128)	(3,381)	(110)
Accrued expenses	22,349	9,299	21,502
Unpaid losses and settlement expenses	293,506	175,697	113,004
Unearned premiums	94,058	46,173	43,708
Current income taxes payable	4,047	(2,665)	(1,434)
Changes in investment in unconsolidated investees:
Undistributed earnings	(37,060)	(20,233)	(20,960)
Dividends received		4,675	13,200
Net cash provided by operating activities	384,905	263,259	276,917
Purchase of:
Fixed income securities, available-for-sale	(733,811)	(518,362)	(539,726)
Equity securities	(140,721)	(77,863)	(89,486)
Property and equipment	(8,310)	(5,768)	(6,955)
Investment in equity method investee	(8,978)	(4,533)
Other	(11,428)	(12,851)	(22,751)
Proceeds from sale of:
Fixed income securities, available-for-sale	63,811	84,587	196,558
Equity securities	180,256	79,368	62,172
Other	7,605	4,328	2,502
Proceeds from call or maturity of:
Fixed income, available-for-sale	376,750	283,107	201,383
Net proceeds from sale of short-term investments			11,550
Net cash used in investing activities	(274,826)	(167,987)	(184,753)
Cash flows from financing activities:
Proceeds from issuance of long-term debt	50,000
Proceeds from stock option exercises	1,838	8,648	9,490
Cash dividends paid	(135,330)	(87,906)	(85,591)
Net cash used in financing activities	(83,492)	(79,258)	(76,101)
Net increase in cash	26,587	16,014	16,063
Cash at beginning of year	62,217	46,203	30,140
Cash at end of year	$ 88,804	$ 62,217	$ 46,203

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES A. DESCRIPTION OF BUSINESS RLI Corp. is an insurance holding company. References to “the Company,” “we,” “our,” “us” or like terms refer to the business of RLI Corp. and its subsidiaries. We underwrite select property and casualty insurance coverages through major subsidiaries collectively known as RLI Insurance Group. We conduct operations principally through three insurance companies. RLI Insurance Company (RLI Ins.), a subsidiary of RLI Corp. and our principal insurance subsidiary, writes multiple lines of insurance on an admitted basis in all 50 states, the District of Columbia, Puerto Rico, the Virgin Islands and Guam. Mt. Hawley Insurance Company (Mt. Hawley), a subsidiary of RLI Ins., writes excess and surplus lines insurance on a non-admitted basis in all 50 states, the District of Columbia, Puerto Rico, the Virgin Islands and Guam. Contractors Bonding and Insurance Company (CBIC), a subsidiary of RLI Ins., writes multiple lines of insurance on an admitted basis in all 50 states and the District of Columbia. B. PRINCIPLES OF CONSOLIDATION AND BASIS OF PRESENTATION The accompanying consolidated financial statements were prepared in conformity with generally accepted accounting principles in the United States of America (GAAP), which differ in some respects from those followed in reports to insurance regulatory authorities. The consolidated financial statements include the accounts of our holding company and our subsidiaries. Intercompany balances and transactions have been eliminated. The Company has evaluated subsequent events through the date these consolidated financial statements were issued. There were no subsequent events requiring adjustment to the financial statements or disclosure. C. ADOPTED ACCOUNTING STANDARDS No new accounting standards applicable in 2021 materially impacted our financial statements. D. PROSPECTIVE ACCOUNTING STANDARDS There are no prospective accounting standards which would have a material impact on our financial statements as of December 31, 2021. E . INVESTMENTS Equity securities are carried at fair value with unrealized gains and losses recorded within net earnings. Investments in fixed income securities are classified into one of three categories: trading, held-to-maturity or available-for-sale. All of our fixed income securities are classified as available-for-sale and reported at fair value. Unrealized gains and losses on these securities are excluded from net earnings but are recorded as a separate component of comprehensive earnings and shareholders’ equity, net of deferred income taxes. Interest on fixed maturities and short-term investments is credited to earnings on an accrual basis. Premiums and discounts are amortized or accreted over the lives of the related fixed maturities. Dividends on equity securities are credited to 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 settlement date. F . CASH AND OTHER INVESTED ASSETS Cash consists of uninvested balances in bank accounts. Other invested assets include investments in low income housing tax credit partnerships (LIHTC), membership in the Federal Home Loan Bank of Chicago (FHLBC) and investments in private funds. Our LIHTC investments are carried at amortized cost, and our investment in FHLBC stock is carried at cost. Due to the nature of cash, the LIHTCs and our membership in the FHLBC, their carrying amounts approximate fair value. The private funds are carried at fair value, using each investment’s net asset value. G . REINSURANCE Ceded unearned premiums and reinsurance balances recoverable on unpaid losses and settlement expenses are reported separately as an asset, rather than being netted with the related liability, since reinsurance does not relieve the Company of our liability to policyholders. Such balances are subject to the credit risk associated with the individual reinsurer. We continually monitor the financial condition of our reinsurers and actively follow up on any past due or disputed amounts. As part of our monitoring efforts, we review reinsurers’ annual financial statements and SEC filings for those that are publicly traded. We also review insurance industry developments that may impact the financial condition of our reinsurers. We analyze the credit risk associated with our reinsurance balances recoverable by monitoring the AM Best and S&P ratings of our reinsurers. In addition, we subject our reinsurance recoverables to detailed recoverability tests, including a segment-based analysis using the average default rating percentage by S&P rating, which assists the Company in assessing the sufficiency of its allowance. Additionally, we perform an in-depth reinsurer financial condition analysis prior to the renewal of our reinsurance placements. Our policy is to charge to earnings, in the form of an allowance, an estimate of unrecoverable amounts from reinsurers. This allowance is reviewed on an ongoing basis to ensure that the amount makes a reasonable provision for reinsurance balances that we may be unable to recover. Once regulatory action (such as receivership, finding of insolvency, order of conservation or order of liquidation) is taken against a reinsurer, the paid and unpaid recoverable for the reinsurer are specifically identified and written off through the use of our allowance for estimated unrecoverable amounts from reinsurers. When we write-off such a balance, it is done in full. We then re-evaluate the remaining allowance and determine whether the balance is sufficient and, if needed, an additional allowance is recognized. H . POLICY ACQUISITION COSTS We defer incremental direct costs that relate to the successful acquisition of new or renewal insurance contracts, including commissions and premium taxes. Acquisition-related costs may be deemed ineligible for deferral when they are based on contingent or performance criteria beyond the basic acquisition of the insurance contract or when efforts to obtain or renew the insurance contract are unsuccessful. All eligible costs are capitalized and charged to expense in proportion to premium revenue recognized. The method followed in computing deferred policy acquisition costs limits the amount of such deferred costs to their estimated realizable value. This process contemplates the premiums to be earned, anticipated losses and settlement expenses and certain other costs expected to be incurred, but does not consider investment income. Judgments as to the ultimate recoverability of such deferred costs are reviewed on a segment basis and are highly dependent upon estimated future loss costs associated with the premiums written. This deferral methodology applies to both gross and ceded premiums and acquisition costs. I . PROPERTY AND EQUIPMENT Property and equipment are presented at cost less accumulated depreciation and are depreciated on a straight-line basis for financial statement purposes over periods ranging from 3 to 10 years for equipment and up to 30 years for buildings and improvements. J . INVESTMENTS IN UNCONSOLIDATED INVESTEES Our investments accounted for under the equity method are primarily related to Maui Jim, Inc. (Maui Jim) and Prime Holdings Insurance Services, Inc. (Prime). We maintain a 40 percent interest in the equity and earnings of Maui Jim, a manufacturer of high-quality sunglasses, and a minority representation on their board of directors. Maui Jim’s chief executive officer owns a controlling majority of the outstanding shares of Maui Jim. We carry this investment at the holding company level as it is not core to our insurance operations. Our investment in Maui Jim was $113.1 million at December 31, 2021 and $90.9 million at December 31, 2020. In 2021, we recorded $22.8 million in investee earnings for Maui Jim, compared to $10.4 million in 2020 and $13.6 million in 2019. As of December 31, 2021, we had a 23 percent interest in the equity and earnings of Prime. Prime writes business through two Illinois domiciled insurance carriers, Prime Insurance Company, an excess and surplus lines company, and Prime Property and Casualty Insurance Inc., an admitted insurance company. Our investment in Prime was $47.2 million at December 31, 2021 and $32.7 million at December 31, 2020. In 2021, we recorded $17.0 million in investee earnings for Prime, compared to $10.8 million in 2020 and $7.4 million in 2019. Additionally, we maintain a quota share reinsurance treaty with Prime, which contributed $22.2 million of gross premiums written and $19.1 million of net premiums earned during 2021, compared to $15.7 million of gross premiums written and $14.3 million of net premiums earned during 2020 and $13.1 million of gross premiums written and $28.7 million of net premiums earned during 2019. The increase in net premiums earned in 2021 from 2020 reflected growth in written premium from Prime, while the decrease in net premiums earned in 2020 from 2019 reflected a reduction in our quota share participation with Prime. Our equity method investments recorded net income of $125.3 million in 2021, $70.4 million in 2020 and $77.3 million in 2019. Additional summarized financial information for our equity method investments as of 2021 and 2020 is outlined in the following table: (in millions) 2021 2020 Total assets $ 1,172.6 $ 837.2 Total liabilities 687.8 473.2 Total equity 484.8 364.0 Approximately $145.8 million of undistributed earnings from our equity method investees were included in our retained earnings as of December 31, 2021. We did not receive any dividends from our equity method investees during 2021, compared to $4.7 million and $13.2 million of dividends received in 2020 and 2019, respectively. We perform annual impairment reviews of our investments in unconsolidated investees, which take into consideration current valuation and operating results. Based upon the most recent reviews, the assets were not impaired. K . GOODWILL AND INTANGIBLE ASSETS The composition of goodwill and intangibles at December 31, 2021 and 2020, is detailed in the following table: (in thousands) 2021 2020 Goodwill Surety $ 40,816 $ 40,816 Casualty 5,246 5,246 Total goodwill $ 46,062 $ 46,062 Intangibles State insurance licenses $ 7,500 $ 7,500 Definite-lived intangibles, net of accumulated amortization of $4,035 at 12/31/21 and $3,878 at 12/31/20 - 157 Total intangibles $ 7,500 $ 7,657 Total goodwill and intangibles $ 53,562 $ 53,719 As the amortization of goodwill and indefinite-lived intangible assets is not permitted, the assets are tested for impairment on an annual basis, or earlier if there is reason to suspect that their values may have been diminished or impaired. Annual impairment testing was performed on each of our goodwill and indefinite-lived intangible assets during 2021. Based upon these reviews, our goodwill and state insurance license indefinite-lived intangible asset were not impaired. In addition, as of December 31, 2021, there were no triggering events on goodwill and intangible assets that would suggest an updated review was necessary. The definite-lived intangible assets are amortized against future operating results based on their estimated useful lives. Amortization of intangible assets was $0.2 million for 2021 and $0.4 million for 2020 and 2019. L . UNPAID LOSSES AND SETTLEMENT EXPENSES The liability for unpaid losses and settlement expenses represents estimates of amounts needed to pay reported and unreported claims and related expenses. The estimates are based on certain actuarial and other assumptions related to the ultimate cost to settle such claims. Such assumptions are subject to occasional changes due to evolving economic, social and political conditions. All estimates are periodically reviewed and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments are reflected in the results of operations in the period in which they are determined. Due to the inherent uncertainty in estimating reserves for losses and settlement expenses, there can be no assurance that the ultimate liability will not exceed recorded amounts. If actual liabilities do exceed recorded amounts, there will be an adverse effect. Furthermore, we may determine that recorded reserves are more than adequate to cover expected losses, which would lead to a reduction in our reserves. M . INSURANCE REVENUE RECOGNITION Insurance premiums are recognized ratably over the term of the contracts, net of ceded reinsurance. Unearned premiums are calculated on a monthly pro rata basis. N . INCOME TAXES We file a consolidated federal income tax return. Federal income taxes are accounted for using the asset and liability method under which deferred income taxes are recognized for the tax consequences of temporary differences by applying enacted statutory tax rates applicable to future years to differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities, operating losses and tax credit carry forwards. The effect on deferred taxes for a change in tax rates is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that all or some of the deferred tax assets will not be realized. We consider uncertainties in income taxes and recognize those in our financial statements as required. As it relates to uncertainties in income taxes, our unrecognized tax benefits, including interest and penalty accruals, are not considered material to the consolidated financial statements. Also, no tax uncertainties are expected to result in significant increases or decreases to unrecognized tax benefits within the next 12-month period. Penalties and interest related to income tax uncertainties, should they occur, would be included in income tax expense in the period in which they are incurred. As an insurance company, we are subject to minimal state income tax liabilities. Since the majority of our income on a state basis is from insurance operations, we pay premium taxes which are calculated as a percentage of gross premiums written in lieu of state income taxes. Premium taxes are a component of policy acquisition costs. O . EARNINGS PER SHARE Basic earnings per share (EPS) is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the dilution that could occur if securities or other contracts to issue common stock or common stock equivalents were exercised or converted into common stock. When inclusion of these items increases the earnings per share or reduces the loss per share, the effect on earnings is anti-dilutive. Under these circumstances, the diluted net earnings or net loss per share is computed excluding these items. The following represents a reconciliation of the numerator and denominator of the basic and diluted EPS computations contained in the consolidated financial statements: Weighted Average Income Shares Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount For the year ended December 31, 2021 Basic EPS Income available to common shareholders $ 279,354 45,230 $ 6.18 Stock options — 482 Diluted EPS Income available to common shareholders and assumed conversions $ 279,354 45,712 $ 6.11 Anti-dilutive options excluded from diluted EPS 214 For the year ended December 31, 2020 Basic EPS Income available to common shareholders $ 157,091 45,000 $ 3.49 Stock options — 376 Diluted EPS Income available to common shareholders and assumed conversions $ 157,091 45,376 $ 3.46 Anti-dilutive options excluded from diluted EPS 384 For the year ended December 31, 2019 Basic EPS Income available to common shareholders $ 191,642 44,734 $ 4.28 Stock options — 523 Diluted EPS Income available to common shareholders and assumed conversions $ 191,642 45,257 $ 4.23 Anti-dilutive options excluded from diluted EPS 65 P . COMPREHENSIVE EARNINGS Our comprehensive earnings include net earnings plus after-tax unrealized gains and losses on our available-for-sale fixed income portfolio. In reporting the components of comprehensive earnings, we used the federal statutory tax rate of 21 percent. Other comprehensive income (loss), as shown in the consolidated statements of earnings and comprehensive earnings, is net of tax expense (benefit) of $(15.7) million, $14.9 million and $17.8 million for 2021, 2020 and 2019, respectively. The table below illustrates the changes in the balance of each component of accumulated other comprehensive earnings for each period presented in the consolidated financial statements. The changes in accumulated other comprehensive earnings also reflect adjustments from the adoption of accounting standards. The adoption of ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, Unrealized Gains/Losses on Available-for-Sale Securities For the Year Ended December 31, (in thousands) 2021 2020 2019 Beginning balance $ 108,714 $ 52,473 $ (14,572 ) Cumulative-effect adjustment of ASU 2016-13 — 22 — Adjusted beginning balance $ 108,714 $ 52,495 $ (14,572 ) Other comprehensive earnings before reclassifications (57,454 ) 58,986 69,560 Amounts reclassified from accumulated other comprehensive earnings (1,434 ) (2,767 ) (2,515 ) Net current period other comprehensive earnings (loss) $ (58,888 ) $ 56,219 $ 67,045 Ending balance $ 49,826 $ 108,714 $ 52,473 Balance of securities for which an allowance for credit losses has not been recognized in net earnings $ 124 $ 470 $ — In 2021 and 2020, credit losses or the sale of an available-for-sale security resulted in amounts being reclassified from accumulated other comprehensive earnings to current period net earnings. In 2019, the sale or other-than-temporary impairment of an available-for-sale security resulted in amounts being reclassified from accumulated other comprehensive earnings to net earnings. The effects of reclassifications out of accumulated other comprehensive earnings by the respective line items of net earnings are presented in the following table. Amount Reclassified from Accumulated Other Comprehensive Earnings (in thousands) Component of Accumulated For the Year Ended December 31, Affected line item in the Other Comprehensive Earnings 2021 2020 2019 Consolidated Statement of Earnings Unrealized gains and losses on available-for-sale securities $ 1,859 $ 3,872 $ 3,184 Net (44 ) (369 ) — Credit losses presented within net realized gains $ 1,815 $ 3,503 $ 3,184 Earnings before income taxes (381 ) (736 ) (669 ) Income tax expense $ 1,434 $ 2,767 $ 2,515 Net earnings Q . FAIR VALUE DISCLOSURES Fair value is defined as the price in the principal market that would be received for an asset to facilitate an orderly transaction between market participants on the measurement date. We determined the fair value of certain financial instruments based on their underlying characteristics and relevant transactions in the marketplace. We maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The following are the levels of the fair value hierarchy and a brief description of the type of valuation inputs that are used to establish each level. Financial assets are classified based upon the lowest level of significant input that is used to determine fair value. Level 1 is applied to valuations based on readily available, unadjusted quoted prices in active markets for identical assets. Level 2 is applied to valuations based upon quoted prices for similar assets in active markets, quoted prices for identical or similar assets in inactive markets; or valuations based on models where the significant inputs are observable (e.g. interest rates, yield curves, prepayment speeds, default rates, loss severities) or can be corroborated by observable market data. Level 3 is applied to valuations that are derived from techniques in which one or more of the significant inputs are unobservable. As a part of management’s process to determine fair value, we utilize widely recognized, third-party pricing sources to determine our fair values. We have obtained an understanding of the third-party pricing sources’ valuation methodologies and inputs. The following is a description of the valuation techniques used for financial assets that are measured at fair value, including the general classification of such assets pursuant to the fair value hierarchy. Corporate, Agencies, Government and Municipal Bonds: The pricing vendor employs a multi-dimensional model which uses standard inputs including (listed in approximate order of priority for use) benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, market bids/offers and other reference data. The pricing vendor also monitors market indicators, as well as industry and economic events. All bonds valued using these techniques are classified as Level 2. All Corporate, Agencies, Government and Municipal securities are deemed Level 2. Mortgage-backed Securities (MBS)/Collateralized Mortgage-backed Securities (CMBS) and Asset-backed Securities (ABS): The pricing vendor evaluation methodology includes principally interest rate movements and new issue data. Evaluation of the tranches (nonvolatile, volatile or credit sensitivity) is based on the pricing vendors’ interpretation of accepted modeling and pricing conventions. This information is then used to determine the cash flows for each tranche, benchmark yields, pre-payment assumptions and to incorporate collateral performance. To evaluate MBS and CMBS volatility, an option adjusted spread model is used in combination with models that simulate interest rate paths to determine market price information. This process allows the pricing vendor to obtain evaluations of a broad universe of securities in a way that reflects changes in yield curve, index rates, implied volatility, mortgage rates and recent trade activity. MBS/CMBS and ABS with corroborated, observable inputs are classified as Level 2. All of our MBS/CMBS and ABS are deemed Level 2. Regulation D Private Placement Securities: The pricing vendor evaluation methodology for these securities includes a combination of observable and unobservable inputs. Observable inputs include public corporate spread matrices classified by sector, rating and average life, as well as investment and non-investment grade matrices created from fixed income indices. Unobservable inputs include a liquidity spread premium calculated based on public corporate spread and private corporate spread matrices. All Regulation D privately-placed bonds are classified as corporate securities and deemed Level 3. For all of our fixed income securities, we periodically conduct a review to assess the reasonableness of the fair values provided by our pricing services. Our review consists of a two-pronged approach. First, we compare prices provided by our pricing services to those provided by an additional source. In some cases, we obtain prices from securities brokers and compare them to the prices provided by our pricing services. In our comparisons, if discrepancies are found, we compare our prices to actual reported trade data for like securities. No changes to the fair values supplied by our pricing services have occurred as a result of our reviews. Based on these assessments, we have determined that the fair values of our fixed income securities provided by our pricing services are reasonable. Common Stock: As of December 31, 2021, nearly all of our common stock holdings were traded on an exchange. Exchange traded equities have readily observable price levels and are classified as Level 1 (fair value based on quoted market prices). Pricing for equity securities not traded on an exchange is provided by a third-party pricing source and is classified as Level 2. Due to the relatively short-term nature of cash, short-term investments, accounts receivable and accounts payable, their carrying amounts are reasonable estimates of fair value. Our investments in private funds, classified as other invested assets, are measured using the investments’ net asset value per share and are not categorized within the fair value hierarchy. The fair value of our long-term debt is discussed further in note 4. R . STOCK-BASED COMPENSATION We expense the estimated fair value of employee stock options and similar awards. We measure compensation cost for awards of equity instruments to employees based on the grant-date fair value of those awards and recognize compensation expense over the service period that the awards are expected to vest. The tax effects related to share-based payments are made through net earnings. See note 8 for further discussion and related disclosures regarding stock options. S . RISKS AND UNCERTAINTIES Certain risks and uncertainties are inherent in our day-to-day operations and in the process of preparing our consolidated financial statements. The more significant risks and uncertainties, as well as our attempt to mitigate, quantify and minimize such risks, are presented below and throughout the notes to the consolidated financial statements. Insurance Risks We compete with a large number of other companies in our selected lines of business. During periods of intense competition for premium, we are vulnerable to the actions of other companies who may seek to write business without the appropriate regard for risk and profitability. The insurance industry is often highly competitive, which can make it difficult to grow or maintain premium volume without sacrificing underwriting discipline and income. Our profitability can be significantly affected by the ability of our underwriters to accurately select and price risk and our claim personnel to appropriately deliver fair outcomes. We attempt to mitigate this risk by incentivizing our underwriters to maximize underwriting profit and remain disciplined in pricing and selecting risks. If we are unable to compete effectively in the markets in which we operate or expand our operations into new markets, our underwriting revenues may decline, as well as overall business results. Our loss reserves are based on estimates and may be inadequate to cover our actual insured losses, which would negatively impact our profitability. As of December 31, 2021, we had $2.0 billion of gross loss and LAE reserves. Significant periods of time often elapse between the occurrence of an insured loss, the reporting of the loss to the Company and our payment of that loss. As part of the reserving process, we review historical data and consider the impact of various factors such as trends in claim frequency and severity, emerging economic and social trends, inflation and changes in the regulatory and litigation environments. If the actual amount of insured losses is greater than the amount we have reserved for these losses, our profitability would suffer. Catastrophe Exposures Our insurance coverages include exposure to catastrophic events. We monitor all catastrophe exposures by quantifying our exposed policy limits in each region and by using computer-assisted modeling techniques. Additionally, we limit our risk to such catastrophes through restraining the total policy limits written in each region and by purchasing reinsurance. Our major catastrophe exposure is to losses caused by earthquakes, primarily on the West Coast. In 2021, we had reinsurance protection of $500 million in excess of $25 million first-dollar retention for earthquakes in California and $525 million in excess of a $25 million first-dollar retention for earthquakes outside of California. These amounts are subject to certain co-participations by the Company on losses in excess of the $25 million retentions. Our second largest catastrophe exposure is to losses caused by wind storms to commercial properties throughout the Gulf and East Coasts, as well as to homes we insure in Hawaii. In 2021, these coverages were supported by $375 million in excess of a $25 million first-dollar retention in traditional catastrophe reinsurance protection, subject to certain co-participations by the Company in the excess layers. In addition, we have incidental exposure to international catastrophic events. Our catastrophe reinsurance treaty renewed on January 1, 2022. We purchased reinsurance protections of $600 million in excess of $25 million first-dollar retention for earthquakes in California and $625 million in excess of a $25 million first-dollar retention for earthquakes outside of California. For other catastrophe events, such as hurricanes, we purchased reinsurance protection of $475 in excess of a $25 million first dollar retention. These amounts are subject to certain co-participations by the Company on losses in excess of the $25 million retentions. We actively manage our catastrophe program to keep our net retention in line with risk tolerances and to optimize the risk/return trade off. Environmental Exposures We are subject to environmental claims and exposures primarily through our commercial excess, general liability and discontinued assumed casualty reinsurance lines of business. Although exposure to environmental claims exists in these lines of business, we seek to mitigate or control the extent of this exposure on the vast majority of this business. Our policies include pollution exclusions that have been continually updated to further strengthen them and our policies primarily cover moderate hazard risks. We offer coverage for low to moderate environmental liability exposures for small contractors and asbestos and mold remediation specialists. We also provide limited coverage for individually underwritten underground storage tanks. The overall exposure is mitigated by focusing on smaller risks with low to moderate exposures. Risks that have large-scale exposures are avoided including petrochemical, chemical, mining, manufacturers and other risks that might be exposed to superfund sites. This business is covered under our casualty ceded reinsurance treaties. We made loss and settlement expense payments on environmental liability claims and have loss and settlement expense reserves for others. We include this historical environmental loss experience with the remaining loss experience in the applicable line of business to project ultimate incurred losses and settlement expenses as well as related incurred but not reported (IBNR) loss and settlement expense reserves. Although historical experience on environmental claims may not accurately reflect future environmental exposures, we used this experience to record loss and settlement expense reserves in the exposed lines of business. See further discussion of environmental exposures in note 6. Reinsurance Reinsurance does not discharge the Company from our primary liability to policyholders, and to the extent that a reinsurer is unable to meet its obligations, we would be liable. We continuously monitor the financial condition of prospective and existing reinsurers. As a result, we purchase reinsurance from a number of financially strong reinsurers. We provide an allowance for reinsurance balances deemed uncollectible. See further discussion of reinsurance exposures in note 5. Investment Risk Our investment portfolio is subject to market, credit and interest rate risks. The equity portfolio will fluctuate with movements in the overall stock market. While the equity portfolio has been constructed to have lower downside risk than the market, the portfolio is positively correlated with movements in domestic stocks. The bond portfolio is affected by interest rate changes and movement in credit spreads. We attempt to mitigate our interest rate and credit risks by constructing a well-diversified portfolio with high-quality securities with varied maturities. Downturns in the financial markets could have a negative effect on our portfolio. However, we attempt to manage this risk through asset allocation, duration and security selection. Liquidity Risk Liquidity is essential to our business and a key component of our concept of asset-liability matching. Our liquidity may be impaired by an inability to collect premium receivable or reinsurance recoverable balances in a timely manner, an inability to sell assets or redeem our investments, an inability to access funds from our insurance subsidiaries, unforeseen outflows of cash or large claim payments or an inability to access debt or equity capital

Investments

Investments	12 Months Ended
	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
Investments	2. INVESTMENTS Our investments are primarily composed of fixed income debt securities and common stock equity securities. All of our debt securities are classified as available-for-sale, which are carried at fair value. Our equity portfolio consists of common stocks and exchange traded funds (ETF), which are carried at fair value. A summary of net investment income is as follows: (in thousands) 2021 2020 2019 Interest on fixed income securities $ 60,624 $ 59,755 $ 60,364 Dividends on equity securities 11,787 9,728 9,950 Interest on cash, short-term investments and other invested assets 2,639 3,379 3,674 Gross investment income $ 75,050 $ 72,862 $ 73,988 Less investment expenses (6,188 ) (4,969 ) (5,118 ) Net investment income $ 68,862 $ 67,893 $ 68,870 Pretax net realized gains (losses) and net changes in unrealized gains (losses) on investments for the years ended December 31 are summarized below. (in thousands) 2021 2020 2019 Net realized gains (losses): Fixed income: Available-for-sale $ 1,859 $ 3,872 $ 3,184 Equity securities 62,512 15,796 14,445 Other (149 ) (1,783 ) (109 ) Total net realized gains (losses) $ 64,222 $ 17,885 $ 17,520 Net changes in unrealized gains (losses) on investments: Equity securities $ 58,459 $ 32,317 $ 78,389 Other invested assets 6,799 (216 ) (299 ) Total unrealized gains (losses) on equity securities recognized in net earnings $ 65,258 $ 32,101 $ 78,090 Fixed income: Available-for-sale $ (71,538 ) $ 67,350 $ 83,758 Investment in unconsolidated investees (3,047 ) 3,444 1,109 Other 44 369 — Total unrealized gains (losses) recognized in other comprehensive earnings $ (74,541 ) $ 71,163 $ 84,867 Net realized gains (losses) and changes in unrealized gains (losses) on investments $ 54,939 $ 121,149 $ 180,477 The change in unrealized gain (loss) position was due to an increase in interest rates, decreasing the fair value of fixed income securities, as well as strong equity market returns. The following is a summary of the disposition of fixed income securities and equities for the years ended December 31, with separate presentations for sales and calls/maturities: SALES Gross Realized Net Realized (in thousands) Proceeds Gains Losses Gain (Loss) 2021 Available-for-sale $ 65,262 $ 2,161 $ (815 ) $ 1,346 Equities 180,256 64,298 (1,786 ) 62,512 2020 Available-for-sale $ 84,697 $ 5,454 $ (1,777 ) $ 3,677 Equities 79,368 25,338 (9,542 ) 15,796 2019 Available-for-sale $ 196,799 $ 4,368 $ (2,167 ) $ 2,201 Equities 62,172 16,938 (2,493 ) 14,445 CALLS/MATURITIES Gross Realized Net Realized (in thousands) Proceeds Gains Losses Gain (Loss) 2021 Available-for-sale $ 376,751 $ 638 $ (125 ) $ 513 2020 Available-for-sale $ 283,107 $ 821 $ (27 ) $ 794 2019 Available-for-sale $ 201,698 $ 1,004 $ (21 ) $ 983 FAIR VALUE MEASUREMENTS Assets measured at fair value on a recurring basis as of December 31, 2021 and 2020, are summarized below: 2021 Quoted in Active Significant Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale U.S. government $ — $ 134,554 $ — $ 134,554 U.S. agency — 32,760 — 32,760 Non-U.S. government & agency — 8,481 — 8,481 Agency MBS — 367,187 — 367,187 ABS/CMBS/MBS* — 264,054 — 264,054 Corporate — 913,577 43,518 957,095 Municipal — 645,756 — 645,756 Total fixed income securities - available-for-sale $ — $ 2,366,369 $ 43,518 $ 2,409,887 Equity securities 613,712 64 — 613,776 Other invested assets — — — — Total $ 613,712 $ 2,366,433 $ 43,518 $ 3,023,663 2020 Quoted in Active Significant Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale U.S. government $ — $ 183,357 $ — $ 183,357 U.S. agency — 32,872 — 32,872 Non-U.S. government & agency — 10,965 — 10,965 Agency MBS — 402,071 — 402,071 ABS/CMBS/MBS* — 218,373 — 218,373 Corporate — 798,794 17,798 816,592 Municipal — 532,396 — 532,396 Total fixed income securities - available-for-sale $ — $ 2,178,828 $ 17,798 $ 2,196,626 Equity securities 523,923 83 — 524,006 Other invested assets 6,068 — — 6,068 Total $ 529,991 $ 2,178,911 $ 17,798 $ 2,726,700 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities The following table summarizes changes in the balance of Regulation D private placement fixed income securities whose fair value was measured using significant unobservable inputs (Level 3). (in thousands) Level 3 Securities Balance as of January 1, 2021 $ 17,798 Net realized and unrealized gains (losses) Included in net earnings as a part of: Net investment income (53 ) Net realized gains (367 ) Included in other comprehensive earnings (170 ) Total net realized and unrealized gains (losses) $ (590 ) Purchases 26,310 Balance as of December 31, 2021 $ 43,518 Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in net realized gains $ (367 ) Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in other comprehensive earnings $ (170 ) The amortized cost and estimated fair value of fixed income securities at December 31, 2021, by contractual maturity, are shown as follows: (in thousands) Amortized Cost Fair Value Due in one year or less $ 57,625 $ 58,134 Due after one year through five years 626,953 647,068 Due after five years through 10 years 537,777 560,653 Due after 10 years 496,778 512,791 ABS/CMBS/MBS* 627,134 631,241 Total available-for-sale $ 2,346,267 $ 2,409,887 * Asset-backed, commercial mortgage-backed and mortgage-backed securities Expected maturities may differ from contractual maturities due to call provisions on some existing securities. The amortized cost and fair value of available-for-sale securities at December 31, 2021 and 2020 are presented in the tables below. Amortized cost does not include the $16.4 million and $14.9 million of accrued interest receivable as of December 31, 2021 and 2020, respectively. 2021 Allowance Gross Gross Amortized for Credit Unrealized Unrealized (in thousands) Cost Losses Gains Losses Fair Value U.S. government $ 127,752 $ — $ 6,846 $ (44 ) $ 134,554 U.S. agency 30,403 — 2,374 (17 ) 32,760 Non-U.S. government & agency 8,297 — 338 (154 ) 8,481 Agency MBS 362,861 — 9,277 (4,951 ) 367,187 ABS/CMBS/MBS* 264,273 — 2,120 (2,339 ) 264,054 Corporate 925,394 (441 ) 37,247 (5,105 ) 957,095 Municipal 627,287 — 22,750 (4,281 ) 645,756 Total fixed income $ 2,346,267 $ (441 ) $ 80,952 $ (16,891 ) $ 2,409,887 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities 2020 Allowance Gross Gross Amortized for Credit Unrealized Unrealized (in thousands) Cost Losses Gains Losses Fair Value U.S. government $ 170,110 $ — $ 13,504 $ (257 ) $ 183,357 U.S. agency 28,902 — 3,970 — 32,872 Non-U.S. government & agency 10,298 — 667 — 10,965 Agency MBS 384,015 — 18,789 (733 ) 402,071 ABS/CMBS/MBS* 213,223 (17 ) 5,580 (413 ) 218,373 Corporate 753,404 (380 ) 64,501 (933 ) 816,592 Municipal 501,515 — 31,099 (218 ) 532,396 Total fixed income $ 2,061,467 $ (397 ) $ 138,110 $ (2,554 ) $ 2,196,626 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities Asset-Backed, Commercial Mortgage-Backed and Mortgage-Backed Securities Eighty-three percent of our collateralized securities carry the highest credit rating by one or more major rating agencies and continue to pay according to contractual terms. For all fixed income securities at an unrealized loss at December 31, 2021, we believe it is probable that we will receive all contractual payments in the form of principal and interest. In addition, we are not required to, nor do we intend to, sell these investments prior to recovering the entire amortized cost basis of each security, which may be at maturity. Municipal Bonds As of December 31, 2021, approximately 48 percent of the municipal fixed income securities in the investment portfolio were general obligations of state and local governments and the remaining 52 percent were revenue based. Ninety percent of our municipal fixed income securities were rated AA or better while 99 percent were rated A or better. Allowance for Credit Losses and Unrealized Losses on Fixed Income Securities We adopted ASU 2016-13, Financial Instruments – Credit Losses, on January 1, 2020, which required the recognition of a reversible allowance for credit losses on available-for-sale fixed income securities. Available-for-sale securities in the fixed income portfolio are subjected to several criteria to determine if those securities should be included in the allowance for expected credit loss evaluation, including: • Changes in technology that may impair the earnings potential of the investment, • The discontinuance of a segment of business that may affect future earnings potential, • Reduction of or non-payment of interest and/or principal, • Specific concerns related to the issuer’s industry or geographic area of operation, • Significant or recurring operating losses, poor cash flows and/or deteriorating liquidity ratios and • Downgrades in credit quality by a major rating agency. If changes in interest rates and credit spreads do not reasonably explain the unrealized loss for an available-for-sale security, or if any of the criteria above indicate a potential credit loss, the security is subjected to a discounted cash flow analysis. Inputs into the discounted cash flow analysis include prepayment assumptions for structured securities, default rates and recoverability rates based on credit rating. The allowance for any security is limited to the amount that the fair value is below amortized cost. As of December 31, 2021, the discounted cash flow analysis resulted in an allowance for credit losses on 7 securities. The following table presents changes in the allowance for expected credit losses on available-for-sale securities: (in thousands) 2021 2020 Beginning balance $ 397 $ — Adoption impact of ASU 2016-13 - $ 28 Increase to allowance from securities for which credit losses were not previously recorded 4 369 Reduction from securities sold during the period (4 ) - Net increase (decrease) from securities that had an allowance at the beginning of the period 44 - Ending balance $ 441 $ 397 No net realized losses were recognized on fixed income securities during 2021 in relation to securities for which we no longer had the intent to hold until recovery and for which the cost basis was written down to fair value, compared to $0.6 million in 2020. All fixed income securities continue to pay the expected coupon payments. We believe we will recover the amortized cost basis of available-for-sale securities that remain in an unrealized loss position. As of December 31, 2021, in addition to the securities included in the allowance for credit losses, the fixed income portfolio contained 443 securities with an unrealized loss position for which an allowance for credit losses had not been recorded. The $16.9 million in associated unrealized losses represents 0.7 percent of the fixed income portfolio’s cost basis and 0.5 nrealized losses at the end of 2021 increased compared to the previous year due to increasing interest rates which reduce the fair value of fixed income securities. The following table illustrates the total value of fixed income securities that were in an unrealized loss position as of December 31, 2021 and 2020. All fixed income securities continue to pay the expected coupon payments and we believe we will recover the amortized cost basis of available-for-sale securities that remain in an unrealized loss position. December 31, 2021 December 31, 2020 12 Mos. 12 Mos. (in thousands) < 12 Mos. & Greater Total < 12 Mos. & Greater Total U.S. government Fair value $ 2,942 $ — $ 2,942 $ 5,680 $ — $ 5,680 Amortized cost 2,986 — 2,986 5,937 — 5,937 Unrealized loss $ (44 ) $ — $ (44 ) $ (257 ) $ — $ (257 ) U.S. agency Fair value $ 1,498 $ — $ 1,498 $ — $ — $ — Amortized cost 1,515 — 1,515 — — — Unrealized loss $ (17 ) $ — $ (17 ) $ — $ — $ — Non-U.S. government & agency Fair value $ 4,346 $ — $ 4,346 $ — $ — $ — Amortized cost 4,500 — 4,500 — — — Unrealized loss $ (154 ) $ — $ (154 ) $ — $ — $ — Agency MBS Fair value $ 102,145 $ 62,669 $ 164,814 $ 43,999 $ — $ 43,999 Amortized cost 104,336 65,429 169,765 44,732 — 44,732 Unrealized loss $ (2,191 ) $ (2,760 ) $ (4,951 ) $ (733 ) $ — $ (733 ) ABS/CMBS/MBS* Fair value $ 150,997 $ 3,935 $ 154,932 $ 32,771 $ 16,161 $ 48,932 Amortized cost 153,235 4,036 157,271 33,094 16,251 49,345 Unrealized loss $ (2,238 ) $ (101 ) $ (2,339 ) $ (323 ) $ (90 ) $ (413 ) Corporate Fair value $ 217,791 $ 53,818 $ 271,609 $ 52,655 $ 6,235 $ 58,890 Amortized cost 221,010 55,704 276,714 53,440 6,383 59,823 Unrealized loss $ (3,219 ) $ (1,886 ) $ (5,105 ) $ (785 ) $ (148 ) $ (933 ) Municipal Fair value $ 162,998 $ 15,037 $ 178,035 $ 25,676 $ — $ 25,676 Amortized cost 166,602 15,714 182,316 25,894 — 25,894 Unrealized loss $ (3,604 ) $ (677 ) $ (4,281 ) $ (218 ) $ — $ (218 ) Total fixed income Fair value $ 642,717 $ 135,459 $ 778,176 $ 160,781 $ 22,396 $ 183,177 Amortized cost 654,184 140,883 795,067 163,097 22,634 185,731 Unrealized loss $ (11,467 ) $ (5,424 ) $ (16,891 ) $ (2,316 ) $ (238 ) $ (2,554 ) * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities Other Invested Assets We had $50.5 million of other invested assets at December 31, 2021, compared to $54.2 million at the end of 2020. Other invested assets include investments in low income housing tax credit (LIHTC) partnerships, membership stock in the Federal Home Loan Bank of Chicago (FHLBC) and investments in private funds. Our LIHTC investments are carried at amortized cost and our investment in FHLBC stock is carried at cost. Due to the nature of the LIHTC and our membership in the FHLBC, their carrying amounts approximate fair value. The private funds are carried at fair value, using each investments’ net asset value. Our LIHTC interests had a balance of $16.6 million at December 31, 2021, compared to $20.3 million at December 31, 2020, and recognized a total tax benefit of $3.6 million during 2021, compared to $3.5 million during 2020 and $2.5 million during 2019. Our unfunded commitment for our LIHTC investments totaled $1.4 million at December 31, 2021 and will be paid out in installments through 2035. Our investments in private funds totaled $28.6 million at December 31, 2021, compared to $32.1 million at December 31, 2020, and we had $8.8 million of associated unfunded commitments at December 31, 2021. Our interest in private funds is generally restricted from being transferred or otherwise redeemed without prior consent by the respective entities and the timed dissolution of the partnerships would trigger redemption. At December 31, 2020, we had a publicly traded common stock with short-term restrictions that limited our ability to sell the security without prior approval. During 2021, our investment in this security became unrestricted and the investment was included in our equity portfolio as of December 31, 2021. Restricted Assets As of December 31, 2021, $64.1 million of investments were pledged as collateral with the FHLBC to ensure timely access to the secured lending facility that ownership of the FHLBC stock provides. On November 10, 2021 RLI Insurance Company borrowed $50.0 million from the FHLBC, which was outstanding as of December 31, 2021. As of December 31, 2021, fixed income securities with a carrying value of $86.2 million were on deposit with regulatory authorities as required by law.

Policy Acquisition Costs

Policy Acquisition Costs	12 Months Ended
	Dec. 31, 2021
Deferred Policy Acquisition Costs Disclosures [Abstract]
Policy Acquisition Costs	3. POLICY ACQUISITION COSTS Policy acquisition costs deferred and amortized to income for the years ended December 31 are summarized as follows: (in thousands) 2021 2020 2019 Deferred policy acquisition costs (DAC), beginning of year $ 88,425 $ 85,044 $ 84,934 Deferred: Direct commissions $ 236,145 $ 200,917 $ 185,164 Premium taxes 17,012 14,783 14,395 Ceding commissions (47,592 ) (42,115 ) (31,140 ) Net deferred $ 205,565 $ 173,585 $ 168,419 Amortized 190,437 170,204 168,309 DAC, end of year $ 103,553 $ 88,425 $ 85,044 Policy acquisition costs: Amortized to expense - DAC $ 190,437 $ 170,204 $ 168,309 Period costs: Ceding commission - contingent (4,303 ) (4,053 ) (3,034 ) Other underwriting expenses 131,334 120,287 123,422 Total policy acquisition costs $ 317,468 $ 286,438 $ 288,697

Debt

Debt	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Debt	4. DEBT As of December 31, 2021, outstanding debt balances totaled $199.7 million, net of unamortized discount and debt issuance costs. On October 2, 2013, we completed a public debt offering, issuing $150.0 million in senior notes maturing September 15, 2023, and paying interest semi-annually at the rate of 4.875 percent. The notes were issued at a discount resulting in proceeds, net of discount and commission, of $148.6 million. The amount of the discount is being charged to income over the life of the debt on an effective yield basis. The carrying value of the senior note was $149.7 million and the estimated fair value was $159.3 million as of December 31, 2021. The fair value of our long-term debt is based on the limited observable prices that reflect thinly traded securities and is therefore classified as a Level 2 liability within the fair value hierarchy. On November 10, 2021, RLI Ins. borrowed $50.0 million from the Federal Home Loan Bank of Chicago. The borrowing matures on November 10, 2023 and has an option pay off the debt early on November 10, 2022. Interest is paid monthly at an annualized rate of 0.84 percent. We paid $7.3 million of interest on our debt in each of the last three years. The average rate on debt was 4.77 percent in 2021 and 4.91 percent in 2020 and 2019. We maintain a revolving line of credit with Bank of Montreal, Chicago Branch, which permits the Company to borrow up to an aggregate principal amount of $60.0 million. This facility was entered into during 2020 and replaced the previous $50.0 million facility with JP Morgan Chase Bank N.A. Under certain conditions, the line may be increased up to an aggregate principal amount of $120.0 million. This facility has a three-year

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2021
Reinsurance Disclosures [Abstract]
Reinsurance	5. REINSURANCE In the ordinary course of business, our insurance subsidiaries assume and cede premiums and selected insured risks with other insurance companies, known as reinsurance. A large portion of the reinsurance is put into effect under contracts known as treaties and, in some instances, by negotiation on each individual risk (known as facultative reinsurance). In addition, there are several types of treaties including quota share, excess of loss and catastrophe reinsurance contracts that protect against losses over stipulated amounts arising from any one occurrence or event. The arrangements allow the Company to pursue greater diversification of business and serve to limit the maximum net loss to a single event, such as a catastrophe. Through the quantification of exposed policy limits in each region and the extensive use of computer-assisted modeling techniques, we monitor the concentration of risks exposed to catastrophic events. Through the purchase of reinsurance, we also limit our net loss on any individual risk to a maximum of $9.7 million, although retentions can vary. Premiums written and earned along with losses and settlement expenses incurred for the years ended December 31 are summarized as follows: (in thousands) 2021 2020 2019 WRITTEN Direct $ 1,313,093 $ 1,107,303 $ 1,039,955 Reinsurance assumed 34,261 29,129 25,047 Reinsurance ceded (289,821 ) (244,344 ) (204,665 ) Net $ 1,057,533 $ 892,088 $ 860,337 EARNED Direct $ 1,222,346 $ 1,062,608 $ 981,121 Reinsurance assumed 30,950 27,651 40,173 Reinsurance ceded (272,393 ) (224,512 ) (182,183 ) Net $ 980,903 $ 865,747 $ 839,111 LOSSES AND SETTLEMENT EXPENSES INCURRED Direct $ 703,903 $ 608,638 $ 521,055 Reinsurance assumed 18,087 18,783 21,951 Reinsurance ceded (265,388 ) (184,537 ) (129,590 ) Net $ 456,602 $ 442,884 $ 413,416 More than 89 percent of our reinsurance recoverables are due from companies with financial strength ratings of A or better by AM Best and S&P rating services. The following table displays net reinsurance balances recoverable, after consideration of collateral, from our top reinsurers as of December 31, 2021. These reinsurers all have financial strength ratings of A or better by AM Best and S&P’s ratings services. Also shown are the amounts of written premium ceded to these reinsurers during the calendar year 2021. Net Reinsurer Ceded AM Best S&P Exposure as of Percent of Premiums Percent of (dollars in thousands) Rating Rating 12/31/2021 Total Written Total Munich Re / HSB A+, Superior AA-, Very Strong $ 102,632 14.5 % $ 34,462 11.9 % Renaissance Re A+, Superior A+, Strong 58,417 8.3 % 25,001 8.6 % Endurance Re A+, Superior A+, Strong 47,136 6.7 % 9,865 3.4 % Scor Re A+, Superior AA-, Very Strong 37,160 5.3 % 13,398 4.6 % Aspen UK Ltd. A, Excellent A-, Strong 36,164 5.1 % 9,402 3.2 % Berkley Insurance Co. A+, Superior A+, Strong 36,033 5.1 % 12,950 4.5 % Hannover Ruckversicherung A+, Superior AA-, Very Strong 33,125 4.7 % 12,942 4.5 % Safety National A++, Superior A+, Strong 32,196 4.6 % 15,544 5.4 % Nationwide Mutual A+, Superior A+, Strong 29,818 4.2 % 17,738 6.1 % Liberty Mutual A, Excellent A, Strong 23,236 3.3 % 7,240 2.5 % All other reinsurers* 270,331 38.2 % 131,279 45.3 % Total ceded exposure $ 706,248 100.0 % $ 289,821 100.0 % * All other reinsurance balances recoverable, when considered by individual reinsurer, are less than 2 percent of shareholders’ equity. The allowances for uncollectible amounts on paid and unpaid recoverables were $16.1 million and $11.2 million, respectively, at December 31, 2021. At December 31, 2020, the amounts were $15.9 million and $8.6 million, respectively. Changes in the allowances during 2021 were due to changes in the amount of reinsurance balances outstanding, the composition of reinsurers from whom the balances were recoverable and their associated S&P default ratings. No write-offs were applied to the allowances in 2021 and $0.2 million was recovered. We have no receivables with a due date that extends beyond one year that are not included in our allowance for uncollectible amounts.

Historical Loss And LAE Develop

Historical Loss And LAE Development	12 Months Ended
	Dec. 31, 2021
Historical Loss And L A E Development Disclosure [Abstract]
Historical Loss And LAE Development	6. HISTORICAL LOSS AND LAE DEVELOPMENT The following table is a reconciliation of our unpaid losses and settlement expenses (LAE) for the years 2021, 2020 and 2019: (in thousands) 2021 2020 2019 Unpaid losses and LAE at beginning of year: Gross $ 1,750,049 $ 1,574,352 $ 1,461,348 Ceded (443,729 ) (384,517 ) (364,999 ) Net $ 1,306,320 $ 1,189,835 $ 1,096,349 Adoption impact of ASU 2016-13 on reinsurance balances recoverable $ — $ (1,345 ) $ — Increase (decrease) in incurred losses and LAE: Current accident year $ 582,065 $ 543,937 $ 488,700 Prior accident years (125,463 ) (101,053 ) (75,284 ) Total incurred $ 456,602 $ 442,884 $ 413,416 Loss and LAE payments for claims incurred: Current accident year $ (101,590 ) $ (93,077 ) $ (80,055 ) Prior accident year (225,863 ) (231,977 ) (239,875 ) Total paid $ (327,453 ) $ (325,054 ) $ (319,930 ) Net unpaid losses and LAE at end of year $ 1,435,469 $ 1,306,320 $ 1,189,835 Unpaid losses and LAE at end of year: Gross $ 2,043,555 $ 1,750,049 $ 1,574,352 Ceded (608,086 ) (443,729 ) (384,517 ) Net $ 1,435,469 $ 1,306,320 $ 1,189,835 We adopted ASU 2016-13, Financial Instruments – Credit Losses, on January 1, 2020, which required financial assets, including reinsurance balances recoverable, to be presented at the net amount expected to be collected. We previously maintained an allowance for uncollectible reinsurance balances prior to the adoption of this update. However, in order to comply with the updated requirements, we released $1.3 million of the allowance on uncollectible reinsurance balances upon adoption. The implementation guidance required the cumulative-effect adjustment be made to the beginning balance of retained earnings, rather than through net earnings like historical changes have and ongoing modifications will continue to be recorded. Loss development occurs when our current estimate of ultimate losses, established through our reserve analysis processes, differs from the initial reserve estimate. The recognition of the changes in initial reserve estimates occurred over time as claims were reported, initial case reserves were established, initial reserves were reviewed in light of additional information and ultimate payments were made on the collective set of claims incurred as of that evaluation date. The new information on the ultimate settlement value of claims is continually updated until all claims in a defined set are settled. As a small specialty insurer with a diversified product portfolio, our experience will ordinarily exhibit fluctuations from period to period. While we attempt to identify and react to changes in the loss environment, we also must consider the volume of claim experience directly available to the Company and interpret any particular period’s indications with a realistic technical understanding of the reliability of those observations. The following is information about incurred and paid loss development as of December 31, 2021, net of reinsurance, as well as cumulative claim frequency, the total of IBNR liabilities included within the net incurred loss amounts and average historical claims duration as of December 31, 2021. The loss information has been disaggregated so that only losses that are expected to develop in a similar manner are grouped together. This has resulted in the presentation of loss information for our property and surety segments at the segment level, while information for our casualty segment has been separated in four groupings: primary occurrence, excess occurrence, claims made and transportation. Primary occurrence includes select lines within the professional services product along with general liability, small commercial and other casualty products. Excess occurrence encompasses commercial excess and personal umbrella, while claims made includes select lines within the professional services product, executive products and other casualty. Reported claim counts represent claim events on a specified policy rather than individual claimants and includes claims that did not or are not expected to result in an incurred loss. The information about incurred and paid claims development for the years ended December 31, 2012 to 2020 is presented as unaudited required supplementary information. Casualty - Primary Occurrence (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 91,807 $ 78,406 $ 65,893 $ 61,072 $ 59,028 $ 59,488 $ 60,328 $ 60,465 $ 60,591 $ 60,155 $ 1,589 5,192 2013 80,823 67,297 62,882 60,329 60,162 59,556 59,116 57,106 57,519 2,096 4,324 2014 88,092 79,497 71,592 67,237 66,389 66,702 65,636 63,727 3,034 4,295 2015 94,835 84,975 83,579 78,675 76,398 75,470 75,438 6,644 4,406 2016 101,950 96,753 90,611 85,449 83,374 79,440 10,352 4,315 2017 119,741 111,391 102,583 95,513 90,759 15,999 4,491 2018 141,513 130,281 125,731 115,076 32,268 4,822 2019 146,011 135,209 120,570 62,738 5,175 2020 145,171 137,439 88,880 4,394 2021 142,797 112,702 3,678 Total $ 942,920 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 5,897 $ 14,539 $ 23,889 $ 33,822 $ 43,276 $ 47,970 $ 51,611 $ 54,391 $ 55,679 $ 56,660 2013 6,334 13,021 22,366 34,786 40,609 45,753 47,783 49,411 50,597 2014 11,436 18,771 29,545 40,270 47,343 52,387 55,965 56,784 2015 10,157 19,902 33,020 45,056 54,270 58,866 62,997 2016 10,142 24,186 35,764 48,042 56,152 60,349 2017 13,154 25,933 38,783 52,823 62,236 2018 15,066 32,365 48,424 63,980 2019 15,698 30,673 41,911 2020 17,096 30,596 2021 14,428 * Presented as unaudited required supplementary information. Total $ 500,538 All outstanding liabilities before 2012, net of reinsurance 10,760 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 453,142 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 12.8 % 13.3 % 14.8 % 16.5 % 11.6 % 7.2 % 5.2 % 2.9 % 2.1 % 1.6 % Casualty - Excess Occurrence (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 29,042 $ 21,558 $ 21,021 $ 21,885 $ 21,231 $ 22,433 $ 23,020 $ 25,286 $ 26,129 $ 26,848 $ 783 867 2013 39,984 34,824 26,857 25,425 25,599 24,922 25,496 25,073 24,836 1,396 949 2014 50,889 39,095 35,119 32,274 33,372 33,458 35,128 35,683 2,622 923 2015 53,672 50,857 47,392 42,840 43,328 42,446 41,690 5,439 699 2016 56,341 49,385 37,676 33,125 30,251 29,671 11,023 646 2017 62,863 55,868 48,363 44,737 43,249 16,698 631 2018 69,362 62,646 54,626 51,023 26,824 590 2019 88,078 89,691 79,083 47,276 603 2020 107,579 98,409 74,182 471 2021 136,433 93,982 371 Total $ 566,925 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 1,315 $ 3,573 $ 8,843 $ 15,380 $ 16,879 $ 17,747 $ 19,310 $ 21,993 $ 22,202 $ 22,246 2013 1,060 5,701 10,967 14,545 16,967 17,956 18,524 21,229 22,154 2014 1,899 4,006 11,002 18,852 22,541 23,376 26,068 28,963 2015 2,048 10,127 19,571 23,184 28,756 31,352 32,752 2016 1,068 3,396 7,441 10,054 12,703 14,400 2017 17 5,679 9,275 15,441 18,470 2018 2,506 5,823 10,801 17,294 2019 4,213 19,044 25,389 2020 2,901 13,856 2021 5,317 * Presented as unaudited required supplementary information. Total $ 200,841 All outstanding liabilities before 2012, net of reinsurance 18,495 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 384,579 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 4.0 % 12.2 % 15.4 % 15.0 % 9.2 % 4.3 % 4.8 % 9.7 % 2.3 % 0.2 % Casualty - Claims Made (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 27,576 $ 26,144 $ 20,727 $ 19,590 $ 18,022 $ 17,612 $ 17,569 $ 20,785 $ 22,325 $ 22,236 $ 207 804 2013 40,095 41,488 44,054 40,288 38,473 37,959 38,352 37,974 37,950 767 1,042 2014 53,929 55,386 58,152 55,350 51,554 53,841 53,783 52,619 1,504 1,305 2015 55,006 47,831 42,206 39,906 39,653 39,619 38,609 2,759 1,338 2016 59,992 67,760 69,493 67,728 64,730 65,078 4,808 1,507 2017 60,572 62,450 62,714 57,450 59,907 9,039 1,648 2018 66,128 62,416 56,468 48,457 17,399 1,391 2019 62,918 61,712 52,224 26,387 1,508 2020 60,278 56,785 43,408 1,287 2021 51,219 42,451 1,112 Total $ 485,084 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 433 $ 4,086 $ 6,898 $ 9,218 $ 10,968 $ 14,378 $ 15,621 $ 16,450 $ 16,892 $ 17,148 2013 792 7,073 18,425 26,121 29,678 32,789 34,535 35,476 36,078 2014 1,705 9,775 27,923 35,755 40,080 44,127 46,122 50,714 2015 2,215 10,738 16,774 20,920 28,795 32,241 33,529 2016 2,060 14,558 27,465 39,370 47,999 52,846 2017 2,455 11,350 22,728 36,522 42,918 2018 1,964 11,965 18,840 24,918 2019 1,839 8,123 14,117 2020 1,488 5,687 2021 999 * Presented as unaudited required supplementary information. Total $ 278,954 All outstanding liabilities before 2012, net of reinsurance 3,575 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 209,705 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 3.2 % 16.1 % 19.6 % 15.7 % 11.6 % 9.5 % 4.3 % 5.0 % 1.8 % 1.2 % Casualty - Transportation (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 21,452 $ 22,203 $ 22,924 $ 23,511 $ 23,689 $ 23,620 $ 23,305 $ 23,731 $ 23,845 $ 23,955 $ 74 2,287 2013 32,742 32,853 32,989 37,673 38,811 39,974 39,309 39,183 39,586 118 2,853 2014 38,361 33,015 36,452 38,590 40,202 40,508 41,156 41,974 297 3,099 2015 38,561 46,258 47,021 46,395 45,162 45,525 45,807 708 3,186 2016 50,430 53,519 54,105 52,277 52,818 53,915 1,235 3,943 2017 55,640 53,641 45,017 43,764 45,351 2,257 3,639 2018 57,597 54,592 38,719 36,468 4,946 3,402 2019 58,297 56,129 43,976 9,024 3,313 2020 43,573 35,524 16,243 1,637 2021 51,322 9,745 2,161 Total $ 417,878 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 4,466 $ 8,533 $ 12,394 $ 17,318 $ 20,931 $ 22,566 $ 22,730 $ 23,180 $ 23,181 $ 23,181 2013 5,306 11,978 19,761 28,220 33,480 35,923 37,327 37,915 38,172 2014 7,125 13,933 19,676 27,457 33,190 38,282 40,006 40,427 2015 6,984 20,709 29,554 37,222 39,339 41,345 42,626 2016 8,923 18,354 30,354 38,001 43,564 47,488 2017 7,979 17,070 24,090 30,260 36,141 2018 6,980 12,827 19,216 24,503 2019 7,148 15,852 21,120 2020 3,986 7,876 2021 5,341 * Presented as unaudited required supplementary information. Total $ 286,875 All outstanding liabilities before 2012, net of reinsurance 528 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 131,531 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 15.5 % 18.3 % 17.0 % 17.1 % 11.7 % 7.4 % 2.8 % 1.5 % 0.3 % 0.0 % Property (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 85,485 $ 80,155 $ 79,181 $ 77,569 $ 79,175 $ 78,125 $ 78,161 $ 78,002 $ 77,924 $ 77,883 $ 7 2,640 2013 63,864 62,090 62,173 62,114 61,914 61,834 61,776 61,623 61,400 36 2,996 2014 56,587 49,441 48,801 48,761 49,217 49,444 49,479 49,520 52 4,562 2015 59,863 56,103 53,958 52,720 53,111 52,781 52,878 96 4,075 2016 62,900 55,594 55,384 55,930 55,424 55,383 177 3,377 2017 90,803 83,273 84,961 82,671 82,319 1,321 2,893 2018 89,091 83,457 79,961 80,470 3,642 2,337 2019 71,232 65,189 61,116 3,193 2,446 2020 118,247 110,466 17,071 2,837 2021 135,447 45,890 2,616 Total $ 766,882 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 39,074 $ 66,509 $ 72,057 $ 73,705 $ 75,640 $ 76,152 $ 77,159 $ 77,323 $ 77,347 $ 77,360 2013 32,208 50,840 57,407 59,259 60,520 61,195 61,325 61,335 61,188 2014 30,550 43,380 46,148 46,528 47,799 49,027 49,259 49,317 2015 32,184 49,348 50,197 51,290 52,078 52,342 52,400 2016 33,134 46,921 51,371 53,006 54,328 54,747 2017 41,314 66,818 74,415 78,360 80,581 2018 37,048 68,264 72,357 75,253 2019 30,703 51,740 55,092 2020 43,192 79,660 2021 57,272 * Presented as unaudited required supplementary information. Total $ 642,870 All outstanding liabilities before 2012, net of reinsurance 640 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 124,652 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 51.3 % 31.8 % 6.6 % 2.8 % 2.3 % 1.1 % 0.5 % 0.1 % -0.1 % 0.0 % Surety (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 17,114 $ 11,452 $ 8,667 $ 8,180 $ 7,867 $ 7,471 $ 7,099 $ 7,082 $ 6,985 $ 7,131 $ 2 1,480 2013 16,080 7,516 6,170 5,399 5,271 5,231 5,209 5,107 5,046 10 1,409 2014 16,450 8,106 5,225 4,427 4,267 4,319 4,266 4,227 8 1,355 2015 16,958 12,957 11,113 10,456 9,792 9,521 9,275 59 1,242 2016 18,928 11,062 9,351 8,895 8,391 7,948 125 1,381 2017 16,127 8,641 8,798 8,116 8,034 306 1,790 2018 16,765 7,227 4,564 3,947 713 1,323 2019 14,785 7,205 5,053 2,047 1,112 2020 19,241 14,840 7,212 748 2021 18,540 15,647 444 Total $ 84,041 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 1,883 $ 6,680 $ 6,726 $ 7,416 $ 7,536 $ 7,406 $ 7,065 $ 6,996 $ 6,941 $ 7,083 2013 1,116 2,856 4,701 4,911 5,098 5,150 5,128 5,061 5,029 2014 722 4,283 4,166 4,059 4,131 4,234 4,214 4,197 2015 3,192 6,719 7,695 9,436 9,183 9,186 9,168 2016 3,087 5,817 6,299 7,640 8,086 7,673 2017 979 2,862 7,062 7,221 7,362 2018 1,835 2,588 2,368 2,536 2019 336 2,433 2,765 2020 835 2,719 2021 1,197 * Presented as unaudited required supplementary information. Total $ 49,729 All outstanding liabilities before 2012, net of reinsurance (68 ) Liabilities for losses and loss adjustment expenses, net of reinsurance $ 34,244 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 21.6 % 39.5 % 13.0 % 7.6 % 2.0 % -0.7 % -1.5 % -0.9 % -0.7 % 2.0 % The following is a reconciliation of the net incurred and paid loss development tables to the liability for unpaid losses and settlement expenses in the consolidated balance sheet: (in thousands) December 31, 2021 December 31, 2020 Net outstanding liabilities: Casualty - Primary Occurrence $ 453,142 $ 432,823 Casualty - Excess Occurrence 384,579 312,827 Casualty - Claims Made 209,705 214,103 Casualty - Transportation 131,531 129,852 Property 124,652 103,383 Surety 34,244 27,009 Unallocated loss adjustment expenses 59,391 54,954 Allowance for uncollectible reinsurance balances recoverable on unpaid losses and settlement expenses 11,188 8,634 Other 27,037 22,735 Liabilities for unpaid loss and settlement expenses, net of reinsurance $ 1,435,469 $ 1,306,320 Reinsurance recoverable on unpaid claims: Casualty - Primary Occurrence $ 43,688 $ 35,202 Casualty - Excess Occurrence 122,092 88,528 Casualty - Claims Made 271,259 223,020 Casualty - Transportation 66,283 53,251 Property 65,098 40,257 Surety 50,743 4,017 Allowance for uncollectible reinsurance balances recoverable on unpaid losses and settlement expenses (11,188 ) (8,634 ) Other 111 8,088 Total reinsurance balances recoverable on unpaid losses and settlement expenses $ 608,086 $ 443,729 Total gross liability for unpaid loss and settlement expenses $ 2,043,555 $ 1,750,049 DETERMINATION OF IBNR Initial carried IBNR reserves are determined through a reserve estimation process. For most casualty and surety products, this process involves the use of an initial loss and allocated loss adjustment expense (ALAE) ratio that is applied to the earned premium for a given period. Payments and case reserves are subtracted from this initial estimate of ultimate loss and ALAE to determine a carried IBNR reserve. For most property products, the IBNR reserves are determined by IBNR percentages applied to premium earned. The percentages are determined based on historical reporting patterns and are updated periodically. No deductions for paid or case reserves are made. Shortly after natural or man-made catastrophes, we review insured locations exposed to the event and model losses based on our own exposures and industry loss estimates of the event. We also consider our knowledge of frequency and severity from early claim reports to determine an appropriate reserve for the catastrophe. Adjustments to the initial loss ratio by product and segment are made where necessary and reflect updated assumptions regarding loss experience, loss trends, price changes and prevailing risk factors. Actuaries perform a ground-up reserve study of the expected value of the unpaid loss and LAE derived using multiple standard actuarial methodologies on a quarterly basis. Each method produces an estimate of ultimate loss by accident year. We review all of these various estimates and assign weights to each based on the characteristics of the product being reviewed. These estimates are then compared to the carried loss reserves to determine the appropriateness of the current reserve balance. In addition, an emergence analysis is completed quarterly to determine if further adjustments are necessary. Upon completion of our loss and LAE estimation analysis, a review of the resulting variance between the indicated reserves and the carried reserves takes place. Our actuaries make a recommendation to management in regards to booked reserves that reflect their analytical assessment and view of estimation risk. After discussion of these analyses and all relevant risk factors, the Loss Reserve Committee, a panel of management including the lead reserving actuary, chief executive officer, chief operating officer, chief financial officer and other executives, confirms the appropriateness of the reserve balances. Actuarial models base future emergence on historic experience, with adjustments for current trends, and the appropriateness of these assumptions involved more uncertainty as of December 31, 2021. We expect the timing of loss emergence and ultimate loss ratios for certain coverages we underwrite will be affected as a result of the spread of COVID-19 and the related economic impact. The industry is experiencing new issues, including the postponement of civil court cases, the extension of various statutes of limitations and changes in settlement trends. Our recorded reserves include consideration of these factors, but the duration and degree to which these issues persist, along with potential legislative, regulatory or judicial actions, could result in loss reserve deficiencies and reduce earnings in future periods . DEVELOPMENT OF IBNR RESERVES The following table summarizes our prior accident years’ loss reserve development by segment for 2021, 2020 and 2019: (in thousands) 2021 2020 2019 Casualty $ (108,632 ) $ (75,075 ) $ (62,497 ) Property (10,981 ) (13,019 ) (4,461 ) Surety (5,850 ) (12,959 ) (8,326 ) Total $ (125,463 ) $ (101,053 ) $ (75,284 ) A discussion of significant components of reserve development for the three most recent calendar years follows: 2021. We experienced favorable emergence relative to prior years’ reserve estimates in all of our segments during 2021. Development from the casualty segment totaled $108.6 million, inclusive of ULAE . Favorable development was experienced across accident years 2014 through 2020, with the largest amounts attributable to accident years 2018 through 2020. We continued to experience emergence that was generally better than previously estimated. We attribute the favorable emergence to loss trends in most lines outperforming our long-term expectations, our underwriters’ ability to select risk and an increasing rate environment. Within the primary occurrence grouping, the general liability product contributed $25.3 million to our favorable development and small commercial was favorable by $7.5 million. Within the excess occurrence grouping, commercial excess was favorable by $10.5 million and personal umbrella developed favorably by $10.4 million. Within the claims made grouping, professional services coverages developed favorably by $14.2 million and executive products developed favorably by $5.9 million. Transportation had $20.1 million of favorable development. Our marine product was the predominant driver of the favorable development in the property segment, accounting for $6.6 million of the $11.0 million total favorable development for the segment, inclusive of ULAE. Accident years 2019 and 2020 made the largest contribution. Commercial property was favorable by $2.0 million. The surety segment experienced $5.9 million of favorable development, inclusive of ULAE. The majority of the favorable development came from the 2019 and 2020 accident years. Contract surety was the main contributor with favorable development of $4.6 million. 2020. We experienced favorable emergence relative to prior years’ reserve estimates in all of our segments during 2020. The casualty segment contributed $75.1 million in favorable development, inclusive of ULAE . Accident years 2017 through 2019 contributed significantly to the favorable development. This was predominantly caused by favorable frequency and severity trends that continued to be better than our long-term expectations. In addition, we believe this to be the result of our underwriters’ ability to select risk as well as an increasing rate environment within many of our casualty sublines. Nearly all of our casualty products contributed to the favorable development. Transportation contributed $19.1 million for the year. Within the primary occurrence grouping, the general liability product contributed $17.9 million to our favorable development. Within the excess occurrence grouping, commercial excess developed favorably by $12.5 million. Within the c laims made grouping, professional services coverages developed favorably by $7.8 million and medical professional liability had $6.1 million of favorable development. The marine product was the primary driver of the favorable development in the property segment. Marine contributed $6.5 million of the $13.0 million total favorable property development, inclusive of ULAE, primarily in accident years 2017 and 2018. Commercial property was favorable by $5.2 million. The surety segment experienced favorable development of $13.0 million, inclusive of ULAE. The majority of the favorable development was from accident year 2019. Contract and commercial surety products were the main contributors with favorable development of $5.9 million and $3.8 million, respectively. 2019. We experienced favorable emergence relative to prior years’ reserve estimates in all of our segments during 2019. The casualty segment contributed $62.5 million in favorable development, inclusive of unallocated loss and adjustment expenses (ULAE) , which is excluded from the incurred loss and loss adjustment expense tables above . Accident years 2017 and 2018 contributed the majority of the favorable development, with earlier years developing favorably in aggregate to a lesser extent. Risk selection by our underwriters continued to provide better results than estimated in our reserving process. Within the primary occurrence grouping, the general liability product contributed $11.8 million to our favorable development. Small commercial products were favorable by $6.3 million. Within the excess occurrence grouping, commercial excess was favorable by $6.8 million and our personal umbrella product developed favorably by $7.8 million. Within the claims made grouping, professional services coverages developed favorably by $10.2 million, which was offset by adverse development of $ 7.3 million on executive products and $ 2.3 million on medical professional liability coverages. Transportation experienced favorable development of $ million , primarily on accident years 201 6 through 201 8 . Marine contributed $2.4 million of the $4.5 million total favorable property development, inclusive of ULAE. Accident years 2017 and 2018 contributed to the marine products’ favorable development. Homeowners’ contributed $1.1 million of favorable development with other commercial property insurance and assumed reinsurance products contributing the balance. The surety segment experienced favorable development of $8.3 million, inclusive of ULAE. The majority of the favorable development was from accident year 2018, while earlier accident years developed slightly adversely. The commercial surety product was the main contributor with favorable development of $5.8 million. Contract surety had favorable development of $4.2 million, which offset $1.7 million of adverse development on miscellaneous surety. ENVIRONMENTAL, ASBESTOS AND MASS TORT EXPOSURES We are subject to environmental site cleanup, asbestos removal and mass tort claims and exposures through our commercial excess, general liability and discontinued assumed casualty reinsurance lines of business. The majority of the exposure is in the excess layers of our commercial excess and assumed reinsurance books of business. The following table represents paid and unpaid environmental, asbestos and mass tort claims data (including incurred but not reported losses) as of December 31, 2021, 2020 and 2019: (in thousands) 2021 2020 2019 Loss and LAE Payments (Cumulative): Gross $ 141,768 $ 139,804 $ 137,485 Ceded (69,576 ) (69,219 ) (68,849 ) Net $ 72,192 $ 70,585 $ 68,636 Unpaid Losses and LAE at End of Year: Gross $ 25,747 $ 22,485 $ 22,616 Ceded (5,718 ) (4,619 ) (5,149 ) Net $ 20,029 $ 17,866 $ 17,467 Our environmental, asbestos and mass tort exposure is limited, relative to other insurers, as a result of entering the affected liability lines after the insurance industry had already recognized environmental and asbestos exposure as a problem and adopted appropriate coverage exclusions. The majority of our reserves are associated with products that went into runoff at least two decades ago. Some are for assumed reinsurance, some are for excess liability business and some followed from the acquisition of Underwriters Indemnity Company in 1999. During 2021, RLI experienced modest emergence of asbestos, environmental and mass tort losses and we increased our IBNR reserves for these exposures. While our environmental exposure is limited, the ultimate liability for this exposure is difficult to assess because of the extensive and complicated litigation involved in the settlement of claims and evolving legislation on issues such as joint and several liability, retroactive liability and standards of cleanup. Additionally, we participate primarily in the excess layers of coverage, where accurate estimates of ultimate loss are more difficult to derive than for primary coverage.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	7. INCOME TAXES The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are summarized below. (in thousands) 2021 2020 Deferred tax assets: Tax discounting of unpaid losses and settlement expenses $ 22,637 $ 21,096 Unearned premium offset 23,080 19,862 Deferred compensation 3,469 2,829 Stock option expense 3,089 2,749 Lease liability 3,796 3,971 Other 367 389 Deferred tax assets before allowance $ 56,438 $ 50,896 Less valuation allowance — — Total deferred tax assets $ 56,438 $ 50,896 Deferred tax liabilities: Net unrealized appreciation of securities $ 76,533 $ 77,639 Deferred policy acquisition costs 21,746 18,569 Lease asset 3,101 3,402 Discounting of unpaid losses and settlement expenses - Tax Cuts and Jobs Act (TCJA) implementation offset 2,545 3,181 Fixed assets 3,518 3,439 Intangible assets 1,537 1,558 Undistributed earnings of unconsolidated investees 29,515 21,813 Other 1,452 1,530 Total deferred tax liabilities $ 139,947 $ 131,131 Net deferred tax liability $ (83,509 ) $ (80,235 ) Income tax expense (benefit) attributable to income from operations for the years ended December 31, 2021, 2020 and 2019, differed from the amounts computed by applying the U.S. federal tax rate of 21 percent to pretax income from continuing operations as demonstrated in the following table: (in thousands) 2021 2020 2019 Provision for income taxes at the statutory federal tax rates $ 72,307 21.0 % $ 39,867 21.0 % $ 48,874 21.0 % Increase (reduction) in taxes resulting from: Excess tax benefit on share-based compensation (3,090 ) (0.9 ) % (3,537 ) (1.8 ) % (3,958 ) (1.7 ) % Tax-exempt interest income (1,219 ) (0.3 ) % (1,293 ) (0.7 ) % (1,238 ) (0.5 ) % Dividends received deduction (891 ) (0.3 ) % (883 ) (0.5 ) % (823 ) (0.4 ) % Investment tax credit (3,491 ) (1.0 ) % (2,435 ) (1.3 ) % — — % ESOP dividends paid deduction (1,566 ) (0.5 ) % (1,083 ) (0.6 ) % (1,122 ) (0.5 ) % Unconsolidated investee dividends — — % (479 ) (0.2 ) % (1,802 ) (0.8 ) % Nondeductible expenses 3,834 1.1 % 1,878 1.0 % 1,649 0.7 % Other items, net (917 ) (0.2 ) % 715 0.4 % (488 ) (0.1 ) % Total $ 64,967 18.9 % $ 32,750 17.3 % $ 41,092 17.7 % Effective rates are dependent upon components of pretax earnings and the related tax effects. The effective rate was higher in 2021 due to higher levels of pretax income, which decreased the impact of tax-favored adjustments on a percentage basis. Our net earnings include equity in earnings of unconsolidated investees, Maui Jim and Prime. The investees do not have a policy or pattern of paying dividends. As a result, we record a deferred tax liability on the earnings at the corporate capital gains rate of 21 percent in anticipation of recovering our investments through means other than through the receipt of dividends, such as a sale. We received a $4.7 million dividend from Prime in 2020 and recognized a $0.5 million tax benefit from applying the lower tax rate applicable to affiliated dividends paid to insurance companies (10.8 percent in 2020), as compared to the corporate capital gains rate on which the deferred tax liabilities were based. In 2019, we received a $13.2 million dividend from Maui Jim and recognized a $1.8 million tax benefit from applying the lower tax rate applicable to affiliated dividends paid to non-insurance companies (7.4 percent in 2019), as compared to the corporate capital gains rate on which the deferred tax liabilities were based. Standing alone, the dividends resulted in a 0.2 percent and 0.8 percent reduction to the 2020 and 2019 effective tax rates, respectively. No dividends were declared from unconsolidated investees in 2021, therefore having no impact to the 2021 effective tax rate. Dividends paid to our Employee Stock Ownership Plan (ESOP) also result in a tax deduction. Dividends paid to the ESOP in 2021, 2020 and 2019 resulted in tax benefits of $1.6 million, $1.1 million and $1.1 million, respectively. These tax benefits reduced the effective tax rate for 2021, 2020 and 2019 by 0.5 percent, 0.6 percent and 0.5 percent and, respectively. We have recorded our deferred tax assets and liabilities using the statutory federal tax rate of 21 percent. We believe it is more likely than not that all deferred tax assets will be recovered, given the carry back availability as well as the results of future operations, which will generate sufficient taxable income to realize the deferred tax asset. In addition, we believe when these deferred items reverse in future years, our taxable income will be taxed at an effective rate of 21 percent. Federal and state income taxes paid in 2021, 2020 and 2019 amounted to $38.6 million, $23.7 million and $25.6 million, respectively. Although we are not currently under audit by the IRS, tax years 2018 through 2021 remain open and are subject to examination.

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2021
Compensation And Retirement Disclosure [Abstract]
Employee Benefits	8. EMPLOYEE BENEFITS EMPLOYEE STOCK OWNERSHIP, 401(K) AND INCENTIVE PLANS We maintain ESOP, 401(k) and incentive plans covering executives, managers and associates. Funding of these plans is primarily dependent upon reaching predetermined levels of operating return on equity, combined ratio and Market Value Potential (MVP). MVP is a compensation model that measures components of comprehensive earnings against a minimum required return on our capital. Bonuses are earned as we generate earnings in excess of this required return. While some management incentive plans may be affected somewhat by other performance factors, the larger influence of corporate performance ensures that the interests of our executives, managers and associates align with those of our shareholders. Our 401(k) plan allows voluntary contributions by employees and permits ESOP diversification transfers for employees meeting certain age and service requirements. We provide a basic 401(k) contribution of 3 percent of eligible compensation. Participants are 100 percent vested in both voluntary and basic contributions. Additionally, an annual discretionary profit-sharing contribution may be made to the ESOP and 401(k), subject to the achievement of certain overall financial goals and board approval. Profit-sharing contributions vest after three years of plan service. Our ESOP and 401(k) cover all employees meeting eligibility requirements. ESOP and 401(k) profit-sharing contributions are approved annually by our board of directors and are expensed in the year earned. ESOP and 401(k)-related expenses (basic and profit-sharing) were $18.0 million, $14.4 million and $15.7 million for 2021, 2020 and 2019, respectively. During 2021, the ESOP purchased 65,815 shares of RLI Corp. stock on the open market at an average price of $107.95 ($7.1 million) relating to the contribution for plan year 2020. Shares held by the ESOP as of December 31, 2021, totaled 2,495,777 and are treated as outstanding in computing our earnings per share. During 2020, the ESOP purchased 94,194 shares of RLI Corp. stock on the open market at an average price of $82.67 ($7.8 million) relating to the contribution for plan year 2019. During 2019, the ESOP purchased 60,768 shares of RLI Corp. stock on the open market at an average price of $69.99 ($4.3 million) relating to the contribution for plan year 2018. The above-mentioned ESOP purchases relate only to our annual contributions to the plan and do not include amounts or shares resulting from the reinvestment of dividends. Annual awards are provided to executives, managers and associates through our incentive plans, provided certain strategic and financial goals are met. Annual expenses for these incentive plans totaled $39.1 million, $26.6 million and $30.1 million for 2021, 2020 and 2019, respectively. DEFERRED COMPENSATION We maintain rabbi trusts for deferred compensation plans for directors, key employees and executive officers through which contributions can be invested in RLI Corp. stock or mutual funds. The employer stock in the plan cannot be diversified and is accounted for as equity, in a manner consistent with the accounting for treasury stock. At December 31, 2021, the trusts’ assets were valued at $51.4 million. STOCK PLANS Our RLI Corp. Long-Term Incentive Plan (2010 LTIP) was in place from 2010 to 2015. The 2010 LTIP provided for equity-based compensation, including stock options, up to a maximum of changes in our capitalization and other events). Between 2010 and 2015, we granted 2,878,000 stock options under the 2010 LTIP. The 2010 LTIP was replaced in 2015. In 2015, our shareholders approved the 2015 RLI Corp. Long-Term Incentive Plan (2015 LTIP), which provides for equity-based compensation and replaced the 2010 LTIP. In conjunction with the adoption of the 2015 LTIP, effective May 7, 2015, options were no longer granted under the 2010 LTIP. Awards under the 2015 LTIP may be in the form of restricted stock, restricted stock units, stock options (non-qualified only), stock appreciation rights, performance units as well as other stock-based awards. Eligibility under the 2015 LTIP is limited to employees and directors of the Company or any affiliate. The granting of awards under the 2015 LTIP is solely at the discretion of the board of directors. The maximum number of shares of common stock available for distribution under the 2015 LTIP is 4,000,000 shares (subject to adjustment for changes in our capitalization and other events). Since the plan’s approval in 2015, we have granted 2,900,420 awards under the 2015 LTIP, including 277,051 in 2021. Compensation expense is based on the probable number of awards expected to vest. The total compensation expense related to equity awards was $6.4 million, $5.4 million and $6.0 million for The total income tax benefit was $1.0 million for 2021 and Stock Options Under the 2015 LTIP, as under the 2010 LTIP, we grant stock options for shares with an exercise price equal to the fair market value of the shares at the date of grant (subject to adjustments for changes in our capitalization, including special dividends and other events as set forth in such plans). Options generally vest and become exercisable ratably over a five-year For most participants, the requisite service period and vesting period will be the same. For participants who are retirement eligible, defined by the plan as those individuals whose age and years of service equals 75, the requisite service period is deemed to be met and options are immediately expensed on the date of grant. For participants who will become retirement eligible during the vesting period, the requisite service period over which expense is recognized is the period between the grant date and the attainment of retirement eligibility. Shares issued upon option exercise are newly issued shares. The following table summarize option activity in 2021: Weighted Aggregate Weighted Average Intrinsic Average Remaining Value Options Exercise Price Contractual Life (in 000’s) Outstanding as of January 1, 2021 1,632,334 $ 70.67 Granted 260,271 109.67 Exercised (215,065 ) 55.50 Cancelled or forfeited (8,215 ) 84.29 Outstanding as of December 31, 2021 1,669,325 $ 78.63 4.90 $ 56,018 Exercisable at December 31, 2021 784,768 $ 67.14 3.66 $ 35,282 The intrinsic value, which is the difference between the fair value and the exercise price, of options exercised was $12.2 million, $15.5 million and $20.0 million during 2021, 2020 and 2019, respectively. The fair value of options were estimated using a Black-Scholes based option pricing model with the following weighted-average grant-date assumptions and weighted-average fair values as of December 31: 2021 2020 2019 Weighted-average fair value of grants $ 17.11 $ 13.24 $ 13.49 Risk-free interest rates 0.75 % 0.39 % 2.26 % Dividend yield 2.06 % 2.30 % 2.69 % Expected volatility 22.73 % 22.67 % 22.71 % Expected option life 4.97 years 4.96 years 4.96 years The risk-free rate was determined based on U.S. treasury yields that most closely approximated the option’s expected life. The dividend yield was determined based on the average annualized quarterly dividends paid during the most recent five-year period and incorporated a consideration for special dividends paid in recent history. The expected volatility was calculated based on the median of the rolling volatilities for the expected life of the options. The expected option life was determined based on historical exercise behavior and the assumption that all outstanding options will be exercised at the midpoint of the current date and remaining contractual term, adjusted for the demographics of the current year’s grant. Restricted Stock Units In addition to stock options, restricted stock units (RSUs) are granted with a value equal to the closing stock price of the Company’s stock on the dates the units are granted. For employees, these units generally have a three-year Weighted Average Grant Date RSUs Fair Value Nonvested at January 1, 2021 47,658 $ 81.53 Granted 16,780 113.02 Reinvested 1,233 108.00 Vested (19,725 ) 72.53 Forfeited (878 ) 94.28 Nonvested at December 31, 2021 45,068 $ 97.67

Statutory Information and Divid

Statutory Information and Dividend Restrictions	12 Months Ended
	Dec. 31, 2021
Statutory Information And Dividend Restrictions Disclosure [Abstract]
STATUTORY INFORMATION AND DIVIDEND RESTRICTIONS	9. STATUTORY INFORMATION AND DIVIDEND RESTRICTIONS The statutory financial statements of our three insurance companies are presented on the basis of accounting practices prescribed or permitted by the Illinois Department of Insurance (IDOI), which has adopted the NAIC’s statutory accounting principles (SAP). We do not use any permitted SAP that differ from NAIC prescribed SAP. In converting from SAP to GAAP, typical adjustments include deferral of policy acquisition costs, the inclusion of statutory non-admitted assets and the inclusion of net unrealized holding gains or losses in shareholders’ equity relating to fixed income securities. The NAIC has risk-based capital (RBC) requirements for insurance companies to calculate and report information under a risk-based formula, which measures statutory capital and surplus needs based upon a regulatory definition of risk relative to the company’s balance sheet and mix of products. As of December 31, 2021, each of our insurance subsidiaries had an RBC amount in excess of the authorized control level RBC, as defined by the NAIC. RLI Insurance Company (RLI Ins.), our principal insurance company subsidiary, had an authorized control level RBC of $225.1 million, $203.9 million and $191.0 million as of December 31, 2021, 2020 and 2019, respectively, compared to actual statutory capital and surplus of $1.2 billion, $1.1 billion and $1.0 billion, respectively, for these same periods. Year-end statutory surplus for 2021 presented in the table below includes $271.2 million of RLI Corp. stock (cost basis of $64.6 million) held by Mt. Hawley Insurance Company, compared to $238.0 million and $190.9 million in 2020 and 2019, respectively. The Securities Valuation Office provides specific guidance for valuing this investment, which is eliminated in our GAAP consolidated financial statements. The following table includes selected information for our insurance subsidiaries for the year ended and as of December 31: (in thousands) 2021 2020 2019 Consolidated net income, statutory basis $ 207,550 $ 120,329 $ 129,625 Consolidated surplus, statutory basis $ 1,240,649 $ 1,121,592 $ 1,029,671 As discussed in note 1.A., our three insurance companies are subsidiaries of RLI Corp., with RLI Ins. as the first-level, or principal, insurance subsidiary. At the holding company (RLI Corp.) level, we rely largely on dividends from our insurance company subsidiaries to meet our obligations for paying principal and interest on outstanding debt, corporate expenses and dividends to RLI Corp. shareholders. As discussed further below, dividend payments to RLI Corp. from our principal insurance subsidiary are restricted by state insurance laws as to the amount that may be paid without prior approval of the insurance regulatory authorities of Illinois. As a result, we may not be able to receive dividends from such subsidiary at times and in amounts necessary to pay desired dividends to RLI Corp. shareholders. On a GAAP basis, as of December 31, 2021, our holding company had $1.2 billion in equity. This includes amounts related to the equity of our insurance subsidiaries, which is subject to regulatory restrictions under state insurance laws. The unrestricted regular dividend payments to our shareholders. If necessary, the holding company also has other potential sources of liquidity that could provide for additional funding to meet corporate obligations or pay shareholder dividends, which include a revolving line of credit, as well as access to capital markets. Ordinary dividends, which may be paid by our principal insurance subsidiary without prior regulatory approval, are subject to certain limitations based upon statutory income, surplus and earned surplus. The maximum ordinary dividend distribution from our principal insurance subsidiary in a rolling 12-month period is limited by Illinois law to the greater of 10 percent of RLI Ins. policyholder surplus, as of December 31 of the preceding year, or the net income of RLI Ins. for the 12-month period ending December 31 of the preceding year. Ordinary dividends are further restricted by the requirement that they be paid from earned surplus. In 2021, 2020 and 2019, our principal insurance subsidiary paid ordinary dividends totaling $70.0 million, $110.0 million and $59.0 million, respectively, to RLI Corp. Any dividend distribution in excess of the ordinary dividend limits is deemed extraordinary and requires prior approval from the IDOI. In 2021, our principal insurance subsidiary sought and received regulatory approval prior to the payment of extraordinary dividends totaling $110.0 million. No extraordinary dividends were paid in 2020 or 2019. As of December 31, 2021, $26.1 million of the net assets of our principal insurance subsidiary are not restricted and could be distributed to RLI Corp. as ordinary dividends. Because the limitations are based upon a rolling 12-month period, the amount and impact of these restrictions vary over time. In addition to restrictions from our principal subsidiary’s insurance regulator, we also consider internal models and how capital adequacy is defined by our rating agencies in determining amounts available for distribution.

Commitments And Contingent Liab

Commitments And Contingent Liabilities	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments And Contingent Liabilities	10. COMMITMENTS AND CONTINGENT LIABILITIES COMMITMENTS As of December 31, 2021, we had $20.1 million of unfunded commitments related to our investments in private funds, low income housing tax credit investments and equity method investees. See note 2 for more information on our investments in private funds and low income housing tax credits. LITIGATION We are party to numerous claims, loss and litigation matters that arise in the normal course of our business. Many of such claims, loss or litigation matters involve claims under policies that we underwrite as an insurer. We believe that the resolution of these claims and losses is not reasonably likely to have a material adverse effect on our financial condition, results of operations or cash flows. From time to time, we are also involved in various other legal proceedings and litigation unrelated to our insurance business that arise in the ordinary course of business operations. Management believes that any liabilities that may arise as a result of these legal matters is not reasonably likely to have a material adverse effect on our financial condition, results of operations or cash flows.

Leases

Leases	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Leases	11. LEASES Right-of-use (ROU) assets are included in the other assets line item and lease liabilities are included in the other liabilities line item of the consolidated balance sheet. We determine if a contract contains a lease at inception and recognize operating lease ROU assets and operating lease liabilities based on the present value of the future minimum lease payments at the commencement date. As our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at the commencement date in determining the present value of future payments. Lease agreements may include options to extend or terminate. The options are exercised at our discretion and are included in operating lease liabilities if it is reasonably certain the option will be exercised. Lease agreements have lease and non-lease components, which are accounted for as a single lease component. Operating lease cost for future minimum lease payments is recognized on a straight-line basis over the lease term. Variable lease cost is expensed in the period in which the obligation is incurred. Sublease income is recognized on a straight-line basis over the sublease term. The components of lease expense and other lease information as of and during the years ended December 31, 2021, 2020 and 2019 are as follows: (in thousands) 2021 2020 2019 Operating lease cost $ 5,131 $ 5,504 $ 5,772 Variable lease cost 1,433 1,346 1,850 Sublease income (508 ) (262 ) — Total lease cost $ 6,056 $ 6,588 $ 7,622 Cash paid for amounts included in measurement of lease liabilities Operating cash flows from operating leases $ 5,738 $ 5,963 $ 5,711 ROU assets obtained in exchange for new operating lease liabilities $ 4,828 $ 81 $ 1,388 Reduction to ROU assets resulting from reduction to lease liabilities $ 1,042 $ 18 $ 1,279 Other non-cash reductions to ROU assets $ 48 $ 1,192 $ — (in thousands) 2021 2020 Operating lease ROU assets $ 14,765 $ 16,200 Operating lease liabilities $ 16,905 $ 19,072 Weighted-average remaining lease term - operating leases 4.52 years 3.87 years Weighted-average discount rate - operating leases 2.02 % 2.32 % Future minimum lease payments under non-cancellable leases as of December 31, 2021 were as follows: (in thousands) 2021 2022 $ 5,353 2023 4,826 2024 2,844 2025 1,481 2026 884 Thereafter 2,283 Total future minimum lease payments $ 17,671 Less imputed interest (766 ) Total operating lease liability $ 16,905

Operating Segment Information

Operating Segment Information	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Operating Segment Information	12. OPERATING SEGMENT INFORMATION The segments of our insurance operations include casualty, property and surety. The casualty portion of our business consists largely of commercial excess, personal umbrella, general liability, transportation and executive products coverages, as well as package business and other specialty coverages, such as professional liability and workers’ compensation for office-based professionals. We also assume a limited amount of hard-to-place risks through a quota share reinsurance agreement. The casualty business is subject to the risk of estimating losses and related loss reserves because the ultimate settlement of a casualty claim may take several years to fully develop. The casualty segment is also subject to inflation risk and may be affected by evolving legislation and court decisions that define the extent of coverage and the amount of compensation due for injuries or losses. Our property segment is comprised primarily of commercial fire, earthquake, difference in conditions and marine coverages. We also offer select personal lines policies, including homeowners’ coverages. Property insurance results are subject to the variability introduced by perils such as earthquakes, fires and hurricanes. Our major catastrophe exposure is to losses caused by earthquakes, primarily on the West Coast. Our second largest catastrophe exposure is to losses caused by wind storms to commercial properties throughout the Gulf and East Coast, as well as to homes we insure in Hawaii. We limit our net aggregate exposure to a catastrophic event by minimizing the total policy limits written in a particular region, purchasing reinsurance and maintaining policy terms and conditions throughout market cycles. We also use computer-assisted modeling techniques to provide estimates that help the Company carefully manage the concentration of risks exposed to catastrophic events. The surety segment specializes in writing small to large-sized commercial and contract surety coverages, including payment and performance bonds. We also offer miscellaneous bonds including license and permit, notary and court bonds. Often, our surety coverages involve a statutory requirement for bonds. While these bonds typically maintain a relatively low loss ratio, losses may fluctuate due to adverse economic conditions affecting the financial viability of our insureds. The contract surety product guarantees the construction work of a commercial contractor for a specific project. Generally, losses occur due to the deterioration of a contractor’s financial condition. This line has historically produced marginally higher loss ratios than other surety lines during economic downturns. Net investment income consists of the interest and dividend income streams from our investments in fixed income and equity securities. Interest and general corporate expenses include the cost of debt, other director and shareholder relations costs and other compensation-related expenses incurred for the benefit of the corporation, but not attributable to the operations of our insurance segments. Investee earnings represent our share in Maui Jim and Prime earnings. We own 40 percent of Maui Jim, a privately-held company which operates in the sunglass and optical goods industries, and 23 percent of Prime Holdings Insurance Services, Inc., a privately-held insurance company which specializes in hard-to-place risks. Our investment in Maui Jim, which is carried at the holding company, is unrelated to our core insurance operations. The following table summarizes our segment data based on the internal structure and reporting of information as it is used by management. The net earnings of each segment are before taxes and include revenues (if applicable), direct product or segment costs (such as commissions and claims costs), as well as allocated costs from various support departments. Assets are not managed at the segment level and therefore are not allocated to segments. REVENUES (in thousands) 2021 2020 2019 Casualty $ 633,639 $ 569,521 $ 558,458 Property 231,837 183,720 164,022 Surety 115,427 112,506 116,631 Net premiums earned $ 980,903 $ 865,747 $ 839,111 Net investment income 68,862 67,893 68,870 Net realized gains 64,222 17,885 17,520 Net unrealized gains on equity securities 65,258 32,101 78,090 Total $ 1,179,245 $ 983,626 $ 1,003,591 INSURANCE EXPENSES (in thousands) 2021 2020 2019 Loss and settlement expenses: Casualty $ 311,627 $ 322,099 $ 330,156 Property 129,924 111,356 73,614 Surety 15,051 9,429 9,646 Total loss and settlement expenses $ 456,602 $ 442,884 $ 413,416 Policy acquisition costs: Casualty $ 179,354 $ 162,058 $ 166,499 Property 72,008 59,926 55,986 Surety 66,106 64,454 66,212 Total policy acquisition costs $ 317,468 $ 286,438 $ 288,697 Other insurance expenses: Casualty $ 47,139 $ 40,937 $ 41,202 Property 18,605 15,620 16,279 Surety 11,163 10,271 11,949 Total other insurance expenses $ 76,907 $ 66,828 $ 69,430 Total $ 850,977 $ 796,150 $ 771,543 NET EARNINGS (in thousands) 2021 2020 2019 Casualty $ 95,519 $ 44,427 $ 20,601 Property 11,300 (3,182 ) 18,143 Surety 23,107 28,352 28,824 Net underwriting income $ 129,926 $ 69,597 $ 67,568 Net investment income 68,862 67,893 68,870 Net realized gains 64,222 17,885 17,520 Net unrealized gains on equity securities 65,258 32,101 78,090 Interest on debt (7,677 ) (7,603 ) (7,588 ) General corporate expense (13,330 ) (10,265 ) (12,686 ) Equity in earnings of unconsolidated investees 37,060 20,233 20,960 Total earnings before incomes taxes $ 344,321 $ 189,841 $ 232,734 Income tax expense 64,967 32,750 41,092 Net earnings $ 279,354 $ 157,091 $ 191,642 The following table further summarizes revenues by major product type within each segment: NET PREMIUMS EARNED Year ended December 31, (in thousands) 2021 2020 2019 CASUALTY Commercial excess and personal umbrella $ 219,437 $ 178,214 $ 140,483 General liability 90,853 91,653 98,880 Professional services 88,855 85,196 81,329 Commercial transportation 83,352 64,624 83,213 Small commercial 64,660 63,357 55,701 Executive products 21,873 26,509 27,088 Other casualty 64,609 59,968 71,764 Total $ 633,639 $ 569,521 $ 558,458 PROPERTY Commercial property $ 107,941 $ 79,406 $ 68,310 Marine 97,745 81,852 74,887 Specialty personal 21,385 19,596 19,316 Other property 4,766 2,866 1,509 Total $ 231,837 $ 183,720 $ 164,022 SURETY Miscellaneous $ 43,982 $ 42,292 $ 44,721 Commercial 43,738 42,872 43,553 Contract 27,707 27,342 28,357 Total $ 115,427 $ 112,506 $ 116,631 Grand total $ 980,903 $ 865,747 $ 839,111

Schedule I-Summary Of Investmen

Schedule I-Summary Of Investments-Other than Investments in Related Parties	12 Months Ended
	Dec. 31, 2021
Summary Of Investments Other Than Investments In Related Parties [Abstract]
Schedule I - Summary Of Investments - Other than Investments in Related Parties	RLI CORP. AND SUBSIDIARIES SCHEDULE I—SUMMARY OF INVESTMENTS—OTHER THAN INVESTMENTS IN RELATED PARTIES December 31, 2021 Column A Column B Column C Column D Amount at (in thousands) which shown in Type of Investment Cost (1) Fair Value the balance sheet Fixed maturities: Bonds: Available-for-sale: U.S. government $ 127,752 $ 134,554 $ 134,554 U.S. agency 30,403 32,760 32,760 Non-U.S. government & agency 8,297 8,481 8,481 Agency MBS 362,861 367,187 367,187 ABS/CMBS/MBS* 264,273 264,054 264,054 Corporate 925,394 957,095 957,095 Municipal 627,287 645,756 645,756 Total available-for-sale $ 2,346,267 $ 2,409,887 $ 2,409,887 Total fixed maturities $ 2,346,267 $ 2,409,887 $ 2,409,887 Equity securities: Common stock: Ind Misc and all other $ 103,261 $ 190,735 $ 190,735 ETFs (Ind/misc) 221,240 423,041 423,041 Total equity securities $ 324,501 $ 613,776 $ 613,776 Cash and short-term investments 88,804 88,804 88,804 Other invested assets 44,435 50,501 50,501 Total investments and cash $ 2,804,007 $ 3,162,968 $ 3,162,968 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities Note: See notes 1E and 2 of Notes to Consolidated Financial Statements. See also the accompanying reports of independent registered public accounting firms starting on page 89 of this report. (1) Original cost of equity securities and, as to fixed maturities, original cost reduced by repayments and adjusted for amortization of premiums or accrual of discounts.

Schedule II -Condensed Financia

Schedule II -Condensed Financial Information of Registrant (Parent Company)	12 Months Ended
	Dec. 31, 2021
Condensed Financial Information Of Parent Company Only Disclosure [Abstract]
Schedule II -Condensed Financial Information of Registrant (Parent Company)	RLI CORP. AND SUBSIDIARIES SCHEDULE II—CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY) CONDENSED BALANCE SHEETS December 31, (in thousands, except share data) 2021 2020 ASSETS Cash $ 1,433 $ 381 Accounts receivable, affiliates 848 — Investments in subsidiaries 1,197,997 1,148,342 Investments in unconsolidated investee 113,052 90,893 Fixed income: Available-for-sale, at fair value 86,483 64,211 (amortized cost of $84,823 and allowance for credit losses of $0 in 2021) (amortized cost of $60,657 and allowance for credit losses of $0 in 2020) Property and equipment, at cost, net of accumulated depreciation of $1,697 in 2021 and $1,629 in 2020 1,711 1,779 Income taxes receivable - current 211 1,500 Other assets 2,907 895 TOTAL ASSETS $ 1,404,642 $ 1,308,001 LIABILITIES AND SHAREHOLDERS’ EQUITY LIABILITIES Accounts payable, affiliates $ — $ 2,556 Income taxes - deferred 21,067 16,988 Bonds payable, long-term debt 149,676 149,489 Interest payable, long-term debt 2,153 2,153 Other liabilities 2,385 837 TOTAL LIABILITIES $ 175,281 $ 172,023 SHAREHOLDERS' EQUITY Common stock ($0.01 par value) (Shares authorized - 200,000,000) (68,219,551 shares issued and 45,289,337 shares outstanding in 2021) (68,072,794 shares issued and 45,142,580 shares outstanding in 2020) $ 682 $ 681 Paid-in capital 343,742 335,365 Accumulated other comprehensive earnings 49,826 108,714 Retained earnings 1,228,110 1,084,217 Deferred compensation 9,642 8,292 Treasury stock, at cost (22,930,214 shares in 2021 and 2020) (402,641 ) (401,291 ) TOTAL SHAREHOLDERS’ EQUITY $ 1,229,361 $ 1,135,978 TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY $ 1,404,642 $ 1,308,001 See Notes to Consolidated Financial Statements. See also the accompanying reports of independent registered public accounting firms starting on page 89 of this report. RLI CORP. AND SUBSIDIARIES SCHEDULE II—CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY)—(continued) CONDENSED STATEMENTS OF EARNINGS AND COMPREHENSIVE EARNINGS Years ended December 31, (in thousands) 2021 2020 2019 Net investment income $ 2,102 $ 1,412 $ 1,656 Net realized gains (losses) (625 ) 501 463 Equity in earnings of unconsolidated investee 22,786 10,368 13,592 Selling, general and administrative expenses (13,330 ) (10,265 ) (12,686 ) Interest expense on debt (7,616 ) (7,603 ) (7,588 ) Earnings (loss) before income taxes $ 3,317 $ (5,587 ) $ (4,563 ) Income tax benefit (1,585 ) (2,885 ) (4,989 ) Net earnings (loss) before equity in net earnings of subsidiaries $ 4,902 $ (2,702 ) $ 426 Equity in net earnings of subsidiaries 274,452 159,793 191,216 Net earnings $ 279,354 $ 157,091 $ 191,642 Other comprehensive earnings (loss), net of tax Unrealized gains (losses) on securities: Unrealized holding gains (losses) arising during the period $ (1,996 ) $ 994 $ 1,727 Less: reclassification adjustment for (gains) losses included in net earnings 500 (390 ) (365 ) Other comprehensive earnings (loss) - parent only $ (1,496 ) $ 604 $ 1,362 Equity in other comprehensive earnings (loss) of subsidiaries/investees (57,392 ) 55,615 65,683 Other comprehensive earnings (loss) $ (58,888 ) $ 56,219 $ 67,045 Comprehensive earnings $ 220,466 $ 213,310 $ 258,687 See Notes to Consolidated Financial Statements. See also the accompanying reports of independent registered public accounting firms starting on page 89 of this report. RLI CORP. AND SUBSIDIARIES SCHEDULE II—CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY)—(continued) CONDENSED STATEMENTS OF CASH FLOWS Years ended December 31, (in thousands) 2021 2020 2019 Cash flows from operating activities Earnings (loss) before equity in net earnings of subsidiaries $ 4,902 $ (2,702 ) $ 426 Adjustments to reconcile net losses to net cash provided by (used in) operating activities: Net realized (gains) losses 625 (501 ) (463 ) Depreciation 68 67 68 Other items, net 3,966 2,270 2,487 Change in: Affiliate balances receivable/payable (3,404 ) 1,246 1,180 Federal income taxes 5,901 1,399 (1,673 ) Changes in investment in unconsolidated investee: Undistributed earnings (22,786 ) (10,368 ) (13,592 ) Dividends received — — 13,200 Net cash provided by (used in) operating activities $ (10,728 ) $ (8,589 ) $ 1,633 Cash flows from investing activities Purchase of: Fixed income, available-for-sale $ (33,373 ) $ (24,950 ) $ (2,507 ) Other (2,904 ) (346 ) — Sale of: Fixed income, available-for-sale 5,306 3,767 14,273 Other 1,245 — — Call or maturity of: Fixed income, available-for-sale 2,878 3,492 29,501 Cash dividends received-subsidiaries 180,000 110,000 34,003 Net cash provided by investing activities $ 153,152 $ 91,963 $ 75,270 Cash flows from financing activities Proceeds from stock option exercises $ 1,838 $ 8,648 $ 9,490 Cash dividends paid (147,422 ) (95,793 ) (93,315 ) Other 4,212 3,802 4,058 Net cash used in financing activities $ (141,372 ) $ (83,343 ) $ (79,767 ) Net increase (decrease) in cash $ 1,052 $ 31 $ (2,864 ) Cash at beginning of year 381 350 3,214 Cash at end of year $ 1,433 $ 381 $ 350 Interest paid on outstanding debt amounted to $7.3 million for 2021, 2020 and 2019, respectively. See Notes to Consolidated Financial Statements. See also the accompanying reports of independent registered public accounting firms starting on page 89 of this report.

Schedule III-Supplementary Insu

Schedule III-Supplementary Insurance Information	12 Months Ended
	Dec. 31, 2021
Supplementary Insurance Information [Abstract]
Schedule III-Supplementary Insurance Information	RLI CORP. AND SUBSIDIARIES SCHEDULE III—SUPPLEMENTARY INSURANCE INFORMATION As of and for the years ended December 31, 2021, 2020 and 2019 Incurred losses Deferred policy Unpaid losses Unearned Net and settlement acquisition and settlement premiums, premiums expenses (in thousands) costs expenses, gross gross earned current year Year ended December 31, 2021 Casualty segment $ 55,760 $ 1,760,469 $ 438,248 $ 633,639 $ 420,259 Property segment 25,764 196,369 168,209 231,837 140,905 Surety segment 22,029 86,717 73,987 115,427 20,901 RLI Insurance Group $ 103,553 $ 2,043,555 $ 680,444 $ 980,903 $ 582,065 Year ended December 31, 2020 Casualty segment $ 48,255 $ 1,567,544 $ 385,736 $ 569,521 $ 397,174 Property segment 19,655 150,008 131,274 183,720 124,375 Surety segment 20,515 32,497 69,376 112,506 22,388 RLI Insurance Group $ 88,425 $ 1,750,049 $ 586,386 $ 865,747 $ 543,937 Year ended December 31, 2019 Casualty segment $ 47,805 $ 1,435,619 $ 354,118 $ 558,458 $ 392,653 Property segment 17,057 100,000 116,624 164,022 78,075 Surety segment 20,182 38,733 69,471 116,631 17,972 RLI Insurance Group $ 85,044 $ 1,574,352 $ 540,213 $ 839,111 $ 488,700 NOTE 1: Investment income is not allocated to the segments, therefore, net investment income has not been provided. See the accompanying reports of independent registered public accounting firms starting on page 89 of this report. RLI CORP. AND SUBSIDIARIES SCHEDULE III—SUPPLEMENTARY INSURANCE INFORMATION (continued) As of and for the years ended December 31, 2021, 2020 and 2019 Incurred losses and settlement Policy Other Net expenses acquisition operating premiums (in thousands) prior year costs expenses written Year ended December 31, 2021 Casualty segment $ (108,632 ) $ 179,354 $ 47,139 $ 674,709 Property segment (10,981 ) 72,008 18,605 262,816 Surety segment (5,850 ) 66,106 11,163 120,008 RLI Insurance Group $ (125,463 ) $ 317,468 $ 76,907 $ 1,057,533 Year ended December 31, 2020 Casualty segment $ (75,075 ) $ 162,058 $ 40,937 $ 583,244 Property segment (13,019 ) 59,926 15,620 196,603 Surety segment (12,959 ) 64,454 10,271 112,241 RLI Insurance Group $ (101,053 ) $ 286,438 $ 66,828 $ 892,088 Year ended December 31, 2019 Casualty segment $ (62,497 ) $ 166,499 $ 41,202 $ 564,979 Property segment (4,461 ) 55,986 16,279 181,974 Surety segment (8,326 ) 66,212 11,949 113,384 RLI Insurance Group $ (75,284 ) $ 288,697 $ 69,430 $ 860,337 See the accompanying reports of independent registered public accounting firms starting on page 89 of this report.

Schedule IV-Reinsurance

Schedule IV-Reinsurance	12 Months Ended
	Dec. 31, 2021
Supplemental Schedule Of Reinsurance Premiums For Insurance Companies [Abstract]
Schedule IV-Reinsurance	RLI CORP. AND SUBSIDIARIES SCHEDULE IV—REINSURANCE Years ended December 31, 2021, 2020 and 2019 Percentage Ceded to Assumed of amount Direct other from other Net assumed (in thousands) amount companies companies amount to net 2021 Casualty segment $ 788,741 $ 185,433 $ 30,331 $ 633,639 4.8 % Property segment 310,630 79,094 301 231,837 0.1 % Surety segment 122,975 7,866 318 115,427 0.3 % RLI Insurance Group premiums earned $ 1,222,346 $ 272,393 $ 30,950 $ 980,903 3.2 % 2020 Casualty segment $ 690,718 $ 148,271 $ 27,074 $ 569,521 4.8 % Property segment 253,781 70,398 337 183,720 0.2 % Surety segment 118,109 5,843 240 112,506 0.2 % RLI Insurance Group premiums earned $ 1,062,608 $ 224,512 $ 27,651 $ 865,747 3.2 % 2019 Casualty segment $ 641,159 $ 122,452 $ 39,751 $ 558,458 7.1 % Property segment 217,657 53,810 175 164,022 0.1 % Surety segment 122,305 5,921 247 116,631 0.2 % RLI Insurance Group premiums earned $ 981,121 $ 182,183 $ 40,173 $ 839,111 4.8 % See the accompanying reports of independent registered public accounting firms starting on page 89 of this report.

Schedule V-Valuation and Qualif

Schedule V-Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2021
Valuation And Qualifying Accounts [Abstract]
Schedule V-Valuation and Qualifying Accounts	RLI CORP. AND SUBSIDIARIES SCHEDULE V—VALUATION AND QUALIFYING ACCOUNTS Years ended December 31, 2021, 2020 and 2019 Balance Amounts Amounts Balance at beginning charged recovered at end of (in thousands) of period to expense (written off) period 2021 Allowance for uncollectible reinsurance $ 24,539 $ 2,863 $ (159 ) $ 27,243 2020 Allowance for uncollectible reinsurance $ 25,066 $ (522 ) $ (5 ) $ 24,539 2019 Allowance for uncollectible reinsurance $ 25,911 $ (647 ) $ (198 ) $ 25,066 See the accompanying reports of independent registered public accounting firms starting on page 89 of this report.

Schedule VI-Supplementary Infor

Schedule VI-Supplementary Information Concerning Property-Casualty Insurance Operations	12 Months Ended
	Dec. 31, 2021
Supplemental Information For Property Casualty Insurance Underwriters [Abstract]
Schedule VI-Supplementary Information Concerning Property-Casualty Insurance Operations	RLI CORP. AND SUBSIDIARIES SCHEDULE VI—SUPPLEMENTARY INFORMATION CONCERNING PROPERTY-CASUALTY INSURANCE OPERATIONS Years ended December 31, 2021, 2020 and 2019 (in thousands) Deferred policy Claims and Unearned Net Net acquisition claim adjustment premiums, premiums investment Affiliation with Registrant (1) costs expense reserves gross earned income 2021 $ 103,553 $ 2,043,555 $ 680,444 $ 980,903 $ 68,862 2020 $ 88,425 $ 1,750,049 $ 586,386 $ 865,747 $ 67,893 2019 $ 85,044 $ 1,574,352 $ 540,213 $ 839,111 $ 68,870 Claims and claim adjustment expenses incurred related to: Amortization Paid claims and Net Current Prior of deferred claim adjustment premiums year year acquisition costs expenses written 2021 $ 582,065 $ (125,463 ) $ 317,468 $ 327,453 $ 1,057,533 2020 $ 543,937 $ (101,053 ) $ 286,438 $ 325,054 $ 892,088 2019 $ 488,700 $ (75,284 ) $ 288,697 $ 319,930 $ 860,337 (1) Consolidated property-casualty insurance operations. See the accompanying reports of independent registered public accounting firms starting on page 89 of this report.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Description of Business	A. DESCRIPTION OF BUSINESS RLI Corp. is an insurance holding company. References to “the Company,” “we,” “our,” “us” or like terms refer to the business of RLI Corp. and its subsidiaries. We underwrite select property and casualty insurance coverages through major subsidiaries collectively known as RLI Insurance Group. We conduct operations principally through three insurance companies. RLI Insurance Company (RLI Ins.), a subsidiary of RLI Corp. and our principal insurance subsidiary, writes multiple lines of insurance on an admitted basis in all 50 states, the District of Columbia, Puerto Rico, the Virgin Islands and Guam. Mt. Hawley Insurance Company (Mt. Hawley), a subsidiary of RLI Ins., writes excess and surplus lines insurance on a non-admitted basis in all 50 states, the District of Columbia, Puerto Rico, the Virgin Islands and Guam. Contractors Bonding and Insurance Company (CBIC), a subsidiary of RLI Ins., writes multiple lines of insurance on an admitted basis in all 50 states and the District of Columbia.
Principles of Consolidation and Basis of Presentation	B. PRINCIPLES OF CONSOLIDATION AND BASIS OF PRESENTATION The accompanying consolidated financial statements were prepared in conformity with generally accepted accounting principles in the United States of America (GAAP), which differ in some respects from those followed in reports to insurance regulatory authorities. The consolidated financial statements include the accounts of our holding company and our subsidiaries. Intercompany balances and transactions have been eliminated. The Company has evaluated subsequent events through the date these consolidated financial statements were issued. There were no subsequent events requiring adjustment to the financial statements or disclosure.
Adopted Accounting Standards	C. ADOPTED ACCOUNTING STANDARDS No new accounting standards applicable in 2021 materially impacted our financial statements.
Prospective Accounting Standards	D. PROSPECTIVE ACCOUNTING STANDARDS There are no prospective accounting standards which would have a material impact on our financial statements as of December 31, 2021.
Investments	E . INVESTMENTS Equity securities are carried at fair value with unrealized gains and losses recorded within net earnings. Investments in fixed income securities are classified into one of three categories: trading, held-to-maturity or available-for-sale. All of our fixed income securities are classified as available-for-sale and reported at fair value. Unrealized gains and losses on these securities are excluded from net earnings but are recorded as a separate component of comprehensive earnings and shareholders’ equity, net of deferred income taxes. Interest on fixed maturities and short-term investments is credited to earnings on an accrual basis. Premiums and discounts are amortized or accreted over the lives of the related fixed maturities. Dividends on equity securities are credited to 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 settlement date.
Cash and Other Invested Assets	F . CASH AND OTHER INVESTED ASSETS Cash consists of uninvested balances in bank accounts. Other invested assets include investments in low income housing tax credit partnerships (LIHTC), membership in the Federal Home Loan Bank of Chicago (FHLBC) and investments in private funds. Our LIHTC investments are carried at amortized cost, and our investment in FHLBC stock is carried at cost. Due to the nature of cash, the LIHTCs and our membership in the FHLBC, their carrying amounts approximate fair value. The private funds are carried at fair value, using each investment’s net asset value.
Reinsurance	G . REINSURANCE Ceded unearned premiums and reinsurance balances recoverable on unpaid losses and settlement expenses are reported separately as an asset, rather than being netted with the related liability, since reinsurance does not relieve the Company of our liability to policyholders. Such balances are subject to the credit risk associated with the individual reinsurer. We continually monitor the financial condition of our reinsurers and actively follow up on any past due or disputed amounts. As part of our monitoring efforts, we review reinsurers’ annual financial statements and SEC filings for those that are publicly traded. We also review insurance industry developments that may impact the financial condition of our reinsurers. We analyze the credit risk associated with our reinsurance balances recoverable by monitoring the AM Best and S&P ratings of our reinsurers. In addition, we subject our reinsurance recoverables to detailed recoverability tests, including a segment-based analysis using the average default rating percentage by S&P rating, which assists the Company in assessing the sufficiency of its allowance. Additionally, we perform an in-depth reinsurer financial condition analysis prior to the renewal of our reinsurance placements. Our policy is to charge to earnings, in the form of an allowance, an estimate of unrecoverable amounts from reinsurers. This allowance is reviewed on an ongoing basis to ensure that the amount makes a reasonable provision for reinsurance balances that we may be unable to recover. Once regulatory action (such as receivership, finding of insolvency, order of conservation or order of liquidation) is taken against a reinsurer, the paid and unpaid recoverable for the reinsurer are specifically identified and written off through the use of our allowance for estimated unrecoverable amounts from reinsurers. When we write-off such a balance, it is done in full. We then re-evaluate the remaining allowance and determine whether the balance is sufficient and, if needed, an additional allowance is recognized.
Policy Acquisition Costs	H . POLICY ACQUISITION COSTS We defer incremental direct costs that relate to the successful acquisition of new or renewal insurance contracts, including commissions and premium taxes. Acquisition-related costs may be deemed ineligible for deferral when they are based on contingent or performance criteria beyond the basic acquisition of the insurance contract or when efforts to obtain or renew the insurance contract are unsuccessful. All eligible costs are capitalized and charged to expense in proportion to premium revenue recognized. The method followed in computing deferred policy acquisition costs limits the amount of such deferred costs to their estimated realizable value. This process contemplates the premiums to be earned, anticipated losses and settlement expenses and certain other costs expected to be incurred, but does not consider investment income. Judgments as to the ultimate recoverability of such deferred costs are reviewed on a segment basis and are highly dependent upon estimated future loss costs associated with the premiums written. This deferral methodology applies to both gross and ceded premiums and acquisition costs.
Property and Equipment	I . PROPERTY AND EQUIPMENT Property and equipment are presented at cost less accumulated depreciation and are depreciated on a straight-line basis for financial statement purposes over periods ranging from 3 to 10 years for equipment and up to 30 years for buildings and improvements.
Investments in Unconsolidated Investees	J . INVESTMENTS IN UNCONSOLIDATED INVESTEES Our investments accounted for under the equity method are primarily related to Maui Jim, Inc. (Maui Jim) and Prime Holdings Insurance Services, Inc. (Prime). We maintain a 40 percent interest in the equity and earnings of Maui Jim, a manufacturer of high-quality sunglasses, and a minority representation on their board of directors. Maui Jim’s chief executive officer owns a controlling majority of the outstanding shares of Maui Jim. We carry this investment at the holding company level as it is not core to our insurance operations. Our investment in Maui Jim was $113.1 million at December 31, 2021 and $90.9 million at December 31, 2020. In 2021, we recorded $22.8 million in investee earnings for Maui Jim, compared to $10.4 million in 2020 and $13.6 million in 2019. As of December 31, 2021, we had a 23 percent interest in the equity and earnings of Prime. Prime writes business through two Illinois domiciled insurance carriers, Prime Insurance Company, an excess and surplus lines company, and Prime Property and Casualty Insurance Inc., an admitted insurance company. Our investment in Prime was $47.2 million at December 31, 2021 and $32.7 million at December 31, 2020. In 2021, we recorded $17.0 million in investee earnings for Prime, compared to $10.8 million in 2020 and $7.4 million in 2019. Additionally, we maintain a quota share reinsurance treaty with Prime, which contributed $22.2 million of gross premiums written and $19.1 million of net premiums earned during 2021, compared to $15.7 million of gross premiums written and $14.3 million of net premiums earned during 2020 and $13.1 million of gross premiums written and $28.7 million of net premiums earned during 2019. The increase in net premiums earned in 2021 from 2020 reflected growth in written premium from Prime, while the decrease in net premiums earned in 2020 from 2019 reflected a reduction in our quota share participation with Prime. Our equity method investments recorded net income of $125.3 million in 2021, $70.4 million in 2020 and $77.3 million in 2019. Additional summarized financial information for our equity method investments as of 2021 and 2020 is outlined in the following table: (in millions) 2021 2020 Total assets $ 1,172.6 $ 837.2 Total liabilities 687.8 473.2 Total equity 484.8 364.0 Approximately $145.8 million of undistributed earnings from our equity method investees were included in our retained earnings as of December 31, 2021. We did not receive any dividends from our equity method investees during 2021, compared to $4.7 million and $13.2 million of dividends received in 2020 and 2019, respectively. We perform annual impairment reviews of our investments in unconsolidated investees, which take into consideration current valuation and operating results. Based upon the most recent reviews, the assets were not impaired.
Goodwill and Intangible Assets	K . GOODWILL AND INTANGIBLE ASSETS The composition of goodwill and intangibles at December 31, 2021 and 2020, is detailed in the following table: (in thousands) 2021 2020 Goodwill Surety $ 40,816 $ 40,816 Casualty 5,246 5,246 Total goodwill $ 46,062 $ 46,062 Intangibles State insurance licenses $ 7,500 $ 7,500 Definite-lived intangibles, net of accumulated amortization of $4,035 at 12/31/21 and $3,878 at 12/31/20 - 157 Total intangibles $ 7,500 $ 7,657 Total goodwill and intangibles $ 53,562 $ 53,719 As the amortization of goodwill and indefinite-lived intangible assets is not permitted, the assets are tested for impairment on an annual basis, or earlier if there is reason to suspect that their values may have been diminished or impaired. Annual impairment testing was performed on each of our goodwill and indefinite-lived intangible assets during 2021. Based upon these reviews, our goodwill and state insurance license indefinite-lived intangible asset were not impaired. In addition, as of December 31, 2021, there were no triggering events on goodwill and intangible assets that would suggest an updated review was necessary. The definite-lived intangible assets are amortized against future operating results based on their estimated useful lives. Amortization of intangible assets was $0.2 million for 2021 and $0.4 million for 2020 and 2019.
Unpaid Losses and Settlement Expense	L . UNPAID LOSSES AND SETTLEMENT EXPENSES The liability for unpaid losses and settlement expenses represents estimates of amounts needed to pay reported and unreported claims and related expenses. The estimates are based on certain actuarial and other assumptions related to the ultimate cost to settle such claims. Such assumptions are subject to occasional changes due to evolving economic, social and political conditions. All estimates are periodically reviewed and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments are reflected in the results of operations in the period in which they are determined. Due to the inherent uncertainty in estimating reserves for losses and settlement expenses, there can be no assurance that the ultimate liability will not exceed recorded amounts. If actual liabilities do exceed recorded amounts, there will be an adverse effect. Furthermore, we may determine that recorded reserves are more than adequate to cover expected losses, which would lead to a reduction in our reserves.
Insurance Revenue Recognition	M . INSURANCE REVENUE RECOGNITION Insurance premiums are recognized ratably over the term of the contracts, net of ceded reinsurance. Unearned premiums are calculated on a monthly pro rata basis.
Income Taxes	N . INCOME TAXES We file a consolidated federal income tax return. Federal income taxes are accounted for using the asset and liability method under which deferred income taxes are recognized for the tax consequences of temporary differences by applying enacted statutory tax rates applicable to future years to differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities, operating losses and tax credit carry forwards. The effect on deferred taxes for a change in tax rates is recognized in income in the period that includes the enactment date. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that all or some of the deferred tax assets will not be realized. We consider uncertainties in income taxes and recognize those in our financial statements as required. As it relates to uncertainties in income taxes, our unrecognized tax benefits, including interest and penalty accruals, are not considered material to the consolidated financial statements. Also, no tax uncertainties are expected to result in significant increases or decreases to unrecognized tax benefits within the next 12-month period. Penalties and interest related to income tax uncertainties, should they occur, would be included in income tax expense in the period in which they are incurred. As an insurance company, we are subject to minimal state income tax liabilities. Since the majority of our income on a state basis is from insurance operations, we pay premium taxes which are calculated as a percentage of gross premiums written in lieu of state income taxes. Premium taxes are a component of policy acquisition costs.
Earnings Per Share	O . EARNINGS PER SHARE Basic earnings per share (EPS) is computed by dividing income available to common shareholders by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the dilution that could occur if securities or other contracts to issue common stock or common stock equivalents were exercised or converted into common stock. When inclusion of these items increases the earnings per share or reduces the loss per share, the effect on earnings is anti-dilutive. Under these circumstances, the diluted net earnings or net loss per share is computed excluding these items. The following represents a reconciliation of the numerator and denominator of the basic and diluted EPS computations contained in the consolidated financial statements: Weighted Average Income Shares Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount For the year ended December 31, 2021 Basic EPS Income available to common shareholders $ 279,354 45,230 $ 6.18 Stock options — 482 Diluted EPS Income available to common shareholders and assumed conversions $ 279,354 45,712 $ 6.11 Anti-dilutive options excluded from diluted EPS 214 For the year ended December 31, 2020 Basic EPS Income available to common shareholders $ 157,091 45,000 $ 3.49 Stock options — 376 Diluted EPS Income available to common shareholders and assumed conversions $ 157,091 45,376 $ 3.46 Anti-dilutive options excluded from diluted EPS 384 For the year ended December 31, 2019 Basic EPS Income available to common shareholders $ 191,642 44,734 $ 4.28 Stock options — 523 Diluted EPS Income available to common shareholders and assumed conversions $ 191,642 45,257 $ 4.23 Anti-dilutive options excluded from diluted EPS 65
Comprehensive Earnings	P . COMPREHENSIVE EARNINGS Our comprehensive earnings include net earnings plus after-tax unrealized gains and losses on our available-for-sale fixed income portfolio. In reporting the components of comprehensive earnings, we used the federal statutory tax rate of 21 percent. Other comprehensive income (loss), as shown in the consolidated statements of earnings and comprehensive earnings, is net of tax expense (benefit) of $(15.7) million, $14.9 million and $17.8 million for 2021, 2020 and 2019, respectively. The table below illustrates the changes in the balance of each component of accumulated other comprehensive earnings for each period presented in the consolidated financial statements. The changes in accumulated other comprehensive earnings also reflect adjustments from the adoption of accounting standards. The adoption of ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, Unrealized Gains/Losses on Available-for-Sale Securities For the Year Ended December 31, (in thousands) 2021 2020 2019 Beginning balance $ 108,714 $ 52,473 $ (14,572 ) Cumulative-effect adjustment of ASU 2016-13 — 22 — Adjusted beginning balance $ 108,714 $ 52,495 $ (14,572 ) Other comprehensive earnings before reclassifications (57,454 ) 58,986 69,560 Amounts reclassified from accumulated other comprehensive earnings (1,434 ) (2,767 ) (2,515 ) Net current period other comprehensive earnings (loss) $ (58,888 ) $ 56,219 $ 67,045 Ending balance $ 49,826 $ 108,714 $ 52,473 Balance of securities for which an allowance for credit losses has not been recognized in net earnings $ 124 $ 470 $ — In 2021 and 2020, credit losses or the sale of an available-for-sale security resulted in amounts being reclassified from accumulated other comprehensive earnings to current period net earnings. In 2019, the sale or other-than-temporary impairment of an available-for-sale security resulted in amounts being reclassified from accumulated other comprehensive earnings to net earnings. The effects of reclassifications out of accumulated other comprehensive earnings by the respective line items of net earnings are presented in the following table. Amount Reclassified from Accumulated Other Comprehensive Earnings (in thousands) Component of Accumulated For the Year Ended December 31, Affected line item in the Other Comprehensive Earnings 2021 2020 2019 Consolidated Statement of Earnings Unrealized gains and losses on available-for-sale securities $ 1,859 $ 3,872 $ 3,184 Net (44 ) (369 ) — Credit losses presented within net realized gains $ 1,815 $ 3,503 $ 3,184 Earnings before income taxes (381 ) (736 ) (669 ) Income tax expense $ 1,434 $ 2,767 $ 2,515 Net earnings
Fair Value Disclosures	Q . FAIR VALUE DISCLOSURES Fair value is defined as the price in the principal market that would be received for an asset to facilitate an orderly transaction between market participants on the measurement date. We determined the fair value of certain financial instruments based on their underlying characteristics and relevant transactions in the marketplace. We maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The following are the levels of the fair value hierarchy and a brief description of the type of valuation inputs that are used to establish each level. Financial assets are classified based upon the lowest level of significant input that is used to determine fair value. Level 1 is applied to valuations based on readily available, unadjusted quoted prices in active markets for identical assets. Level 2 is applied to valuations based upon quoted prices for similar assets in active markets, quoted prices for identical or similar assets in inactive markets; or valuations based on models where the significant inputs are observable (e.g. interest rates, yield curves, prepayment speeds, default rates, loss severities) or can be corroborated by observable market data. Level 3 is applied to valuations that are derived from techniques in which one or more of the significant inputs are unobservable. As a part of management’s process to determine fair value, we utilize widely recognized, third-party pricing sources to determine our fair values. We have obtained an understanding of the third-party pricing sources’ valuation methodologies and inputs. The following is a description of the valuation techniques used for financial assets that are measured at fair value, including the general classification of such assets pursuant to the fair value hierarchy. Corporate, Agencies, Government and Municipal Bonds: The pricing vendor employs a multi-dimensional model which uses standard inputs including (listed in approximate order of priority for use) benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, market bids/offers and other reference data. The pricing vendor also monitors market indicators, as well as industry and economic events. All bonds valued using these techniques are classified as Level 2. All Corporate, Agencies, Government and Municipal securities are deemed Level 2. Mortgage-backed Securities (MBS)/Collateralized Mortgage-backed Securities (CMBS) and Asset-backed Securities (ABS): The pricing vendor evaluation methodology includes principally interest rate movements and new issue data. Evaluation of the tranches (nonvolatile, volatile or credit sensitivity) is based on the pricing vendors’ interpretation of accepted modeling and pricing conventions. This information is then used to determine the cash flows for each tranche, benchmark yields, pre-payment assumptions and to incorporate collateral performance. To evaluate MBS and CMBS volatility, an option adjusted spread model is used in combination with models that simulate interest rate paths to determine market price information. This process allows the pricing vendor to obtain evaluations of a broad universe of securities in a way that reflects changes in yield curve, index rates, implied volatility, mortgage rates and recent trade activity. MBS/CMBS and ABS with corroborated, observable inputs are classified as Level 2. All of our MBS/CMBS and ABS are deemed Level 2. Regulation D Private Placement Securities: The pricing vendor evaluation methodology for these securities includes a combination of observable and unobservable inputs. Observable inputs include public corporate spread matrices classified by sector, rating and average life, as well as investment and non-investment grade matrices created from fixed income indices. Unobservable inputs include a liquidity spread premium calculated based on public corporate spread and private corporate spread matrices. All Regulation D privately-placed bonds are classified as corporate securities and deemed Level 3. For all of our fixed income securities, we periodically conduct a review to assess the reasonableness of the fair values provided by our pricing services. Our review consists of a two-pronged approach. First, we compare prices provided by our pricing services to those provided by an additional source. In some cases, we obtain prices from securities brokers and compare them to the prices provided by our pricing services. In our comparisons, if discrepancies are found, we compare our prices to actual reported trade data for like securities. No changes to the fair values supplied by our pricing services have occurred as a result of our reviews. Based on these assessments, we have determined that the fair values of our fixed income securities provided by our pricing services are reasonable. Common Stock: As of December 31, 2021, nearly all of our common stock holdings were traded on an exchange. Exchange traded equities have readily observable price levels and are classified as Level 1 (fair value based on quoted market prices). Pricing for equity securities not traded on an exchange is provided by a third-party pricing source and is classified as Level 2. Due to the relatively short-term nature of cash, short-term investments, accounts receivable and accounts payable, their carrying amounts are reasonable estimates of fair value. Our investments in private funds, classified as other invested assets, are measured using the investments’ net asset value per share and are not categorized within the fair value hierarchy. The fair value of our long-term debt is discussed further in note 4.
Stock-Based Compensation	R . STOCK-BASED COMPENSATION We expense the estimated fair value of employee stock options and similar awards. We measure compensation cost for awards of equity instruments to employees based on the grant-date fair value of those awards and recognize compensation expense over the service period that the awards are expected to vest. The tax effects related to share-based payments are made through net earnings. See note 8 for further discussion and related disclosures regarding stock options.
Risk and Uncertainties	S . RISKS AND UNCERTAINTIES Certain risks and uncertainties are inherent in our day-to-day operations and in the process of preparing our consolidated financial statements. The more significant risks and uncertainties, as well as our attempt to mitigate, quantify and minimize such risks, are presented below and throughout the notes to the consolidated financial statements. Insurance Risks We compete with a large number of other companies in our selected lines of business. During periods of intense competition for premium, we are vulnerable to the actions of other companies who may seek to write business without the appropriate regard for risk and profitability. The insurance industry is often highly competitive, which can make it difficult to grow or maintain premium volume without sacrificing underwriting discipline and income. Our profitability can be significantly affected by the ability of our underwriters to accurately select and price risk and our claim personnel to appropriately deliver fair outcomes. We attempt to mitigate this risk by incentivizing our underwriters to maximize underwriting profit and remain disciplined in pricing and selecting risks. If we are unable to compete effectively in the markets in which we operate or expand our operations into new markets, our underwriting revenues may decline, as well as overall business results. Our loss reserves are based on estimates and may be inadequate to cover our actual insured losses, which would negatively impact our profitability. As of December 31, 2021, we had $2.0 billion of gross loss and LAE reserves. Significant periods of time often elapse between the occurrence of an insured loss, the reporting of the loss to the Company and our payment of that loss. As part of the reserving process, we review historical data and consider the impact of various factors such as trends in claim frequency and severity, emerging economic and social trends, inflation and changes in the regulatory and litigation environments. If the actual amount of insured losses is greater than the amount we have reserved for these losses, our profitability would suffer. Catastrophe Exposures Our insurance coverages include exposure to catastrophic events. We monitor all catastrophe exposures by quantifying our exposed policy limits in each region and by using computer-assisted modeling techniques. Additionally, we limit our risk to such catastrophes through restraining the total policy limits written in each region and by purchasing reinsurance. Our major catastrophe exposure is to losses caused by earthquakes, primarily on the West Coast. In 2021, we had reinsurance protection of $500 million in excess of $25 million first-dollar retention for earthquakes in California and $525 million in excess of a $25 million first-dollar retention for earthquakes outside of California. These amounts are subject to certain co-participations by the Company on losses in excess of the $25 million retentions. Our second largest catastrophe exposure is to losses caused by wind storms to commercial properties throughout the Gulf and East Coasts, as well as to homes we insure in Hawaii. In 2021, these coverages were supported by $375 million in excess of a $25 million first-dollar retention in traditional catastrophe reinsurance protection, subject to certain co-participations by the Company in the excess layers. In addition, we have incidental exposure to international catastrophic events. Our catastrophe reinsurance treaty renewed on January 1, 2022. We purchased reinsurance protections of $600 million in excess of $25 million first-dollar retention for earthquakes in California and $625 million in excess of a $25 million first-dollar retention for earthquakes outside of California. For other catastrophe events, such as hurricanes, we purchased reinsurance protection of $475 in excess of a $25 million first dollar retention. These amounts are subject to certain co-participations by the Company on losses in excess of the $25 million retentions. We actively manage our catastrophe program to keep our net retention in line with risk tolerances and to optimize the risk/return trade off. Environmental Exposures We are subject to environmental claims and exposures primarily through our commercial excess, general liability and discontinued assumed casualty reinsurance lines of business. Although exposure to environmental claims exists in these lines of business, we seek to mitigate or control the extent of this exposure on the vast majority of this business. Our policies include pollution exclusions that have been continually updated to further strengthen them and our policies primarily cover moderate hazard risks. We offer coverage for low to moderate environmental liability exposures for small contractors and asbestos and mold remediation specialists. We also provide limited coverage for individually underwritten underground storage tanks. The overall exposure is mitigated by focusing on smaller risks with low to moderate exposures. Risks that have large-scale exposures are avoided including petrochemical, chemical, mining, manufacturers and other risks that might be exposed to superfund sites. This business is covered under our casualty ceded reinsurance treaties. We made loss and settlement expense payments on environmental liability claims and have loss and settlement expense reserves for others. We include this historical environmental loss experience with the remaining loss experience in the applicable line of business to project ultimate incurred losses and settlement expenses as well as related incurred but not reported (IBNR) loss and settlement expense reserves. Although historical experience on environmental claims may not accurately reflect future environmental exposures, we used this experience to record loss and settlement expense reserves in the exposed lines of business. See further discussion of environmental exposures in note 6. Reinsurance Reinsurance does not discharge the Company from our primary liability to policyholders, and to the extent that a reinsurer is unable to meet its obligations, we would be liable. We continuously monitor the financial condition of prospective and existing reinsurers. As a result, we purchase reinsurance from a number of financially strong reinsurers. We provide an allowance for reinsurance balances deemed uncollectible. See further discussion of reinsurance exposures in note 5. Investment Risk Our investment portfolio is subject to market, credit and interest rate risks. The equity portfolio will fluctuate with movements in the overall stock market. While the equity portfolio has been constructed to have lower downside risk than the market, the portfolio is positively correlated with movements in domestic stocks. The bond portfolio is affected by interest rate changes and movement in credit spreads. We attempt to mitigate our interest rate and credit risks by constructing a well-diversified portfolio with high-quality securities with varied maturities. Downturns in the financial markets could have a negative effect on our portfolio. However, we attempt to manage this risk through asset allocation, duration and security selection. Liquidity Risk Liquidity is essential to our business and a key component of our concept of asset-liability matching. Our liquidity may be impaired by an inability to collect premium receivable or reinsurance recoverable balances in a timely manner, an inability to sell assets or redeem our investments, an inability to access funds from our insurance subsidiaries, unforeseen outflows of cash or large claim payments or an inability to access debt or equity capital markets. This situation may arise due to circumstances that we may be unable to control, such as a general market disruption, an operational problem that affects third parties or the Company, or even by the perception among market participants that we, or other market participants, are experiencing greater liquidity risk. Our credit ratings are important to our liquidity. A reduction in our credit ratings could adversely affect our liquidity and competitive position by increasing our borrowing costs or limiting our access to the capital markets. Financial Statements The preparation of the accompanying consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions about future events. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenues and expenses. The most significant of these amounts is the liability for unpaid losses and settlement expenses. Other estimates include investment valuation, the allowance for credit losses on fixed income securities, the collectability of reinsurance balances, recoverability of deferred tax assets and deferred policy acquisition costs. These estimates and assumptions are based on management’s best estimates and judgment. Management evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors, including the current economic environment, which management believes to be reasonable under the circumstances. We adjust such estimates and assumptions when facts and circumstances dictate. Although recorded estimates are supported by actuarial computations and other supportive data, the estimates are ultimately based on our expectations of future events. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in those estimates resulting from continuing changes in the economic environment will be reflected in the consolidated financial statements in future periods. External Factors Our insurance subsidiaries are highly regulated by the state in which they are incorporated and by the states in which they do business. Such regulations, among other things, limit the amount of dividends, impose restrictions on the amount and types of investments and regulate rates insurers may charge for various coverages. We are also subject to insolvency and guaranty fund assessments for various programs designed to ensure policyholder indemnification. We generally accrue an assessment during the period in which it becomes probable that a liability has been incurred from an insolvency and the amount of the related assessment can be reasonably estimated. The National Association of Insurance Commissioners (NAIC) has developed Property and Casualty Risk-Based Capital (RBC) standards that relate an insurer’s reported statutory surplus to the risks inherent in its overall operations. The RBC formula uses the statutory annual statement to calculate the minimum indicated capital level to support investment and underwriting risk. The NAIC model law calls for various levels of regulatory action based on the magnitude of an indicated RBC capital deficiency, if any. We regularly monitor our subsidiaries’ internal capital requirements and the NAIC’s RBC developments. As of December 31, 2021, we determined that our capital levels are well in excess of the minimum capital requirements for all RBC action levels and that our capital levels are sufficient to support the level of risk inherent in our operations. See note 9 for further discussion of statutory information and related insurance regulatory restrictions. In addition, ratings are a critical factor in establishing the competitive position of insurance companies. Our insurance companies are rated by AM Best, S&P and Moody’s. Their ratings reflect their opinions of an insurance company’s and an insurance holding company’s financial strength, operating performance, strategic position and ability to meet its obligations to policyholders.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Schedule of Summarized Financial Information of Equity Method Investments	(in millions) 2021 2020 Total assets $ 1,172.6 $ 837.2 Total liabilities 687.8 473.2 Total equity 484.8 364.0
Schedule of Goodwill and Intangible Assets	(in thousands) 2021 2020 Goodwill Surety $ 40,816 $ 40,816 Casualty 5,246 5,246 Total goodwill $ 46,062 $ 46,062 Intangibles State insurance licenses $ 7,500 $ 7,500 Definite-lived intangibles, net of accumulated amortization of $4,035 at 12/31/21 and $3,878 at 12/31/20 - 157 Total intangibles $ 7,500 $ 7,657 Total goodwill and intangibles $ 53,562 $ 53,719
Schedule of Reconciliation of Numerator and Denominator of the Basic and Diluted Earnings Per Share Computations	Weighted Average Income Shares Per Share (in thousands, except per share data) (Numerator) (Denominator) Amount For the year ended December 31, 2021 Basic EPS Income available to common shareholders $ 279,354 45,230 $ 6.18 Stock options — 482 Diluted EPS Income available to common shareholders and assumed conversions $ 279,354 45,712 $ 6.11 Anti-dilutive options excluded from diluted EPS 214 For the year ended December 31, 2020 Basic EPS Income available to common shareholders $ 157,091 45,000 $ 3.49 Stock options — 376 Diluted EPS Income available to common shareholders and assumed conversions $ 157,091 45,376 $ 3.46 Anti-dilutive options excluded from diluted EPS 384 For the year ended December 31, 2019 Basic EPS Income available to common shareholders $ 191,642 44,734 $ 4.28 Stock options — 523 Diluted EPS Income available to common shareholders and assumed conversions $ 191,642 45,257 $ 4.23 Anti-dilutive options excluded from diluted EPS 65
Schedule of Changes in the Balance of Each Component of Accumulated Other Comprehensive Earnings	Unrealized Gains/Losses on Available-for-Sale Securities For the Year Ended December 31, (in thousands) 2021 2020 2019 Beginning balance $ 108,714 $ 52,473 $ (14,572 ) Cumulative-effect adjustment of ASU 2016-13 — 22 — Adjusted beginning balance $ 108,714 $ 52,495 $ (14,572 ) Other comprehensive earnings before reclassifications (57,454 ) 58,986 69,560 Amounts reclassified from accumulated other comprehensive earnings (1,434 ) (2,767 ) (2,515 ) Net current period other comprehensive earnings (loss) $ (58,888 ) $ 56,219 $ 67,045 Ending balance $ 49,826 $ 108,714 $ 52,473 Balance of securities for which an allowance for credit losses has not been recognized in net earnings $ 124 $ 470 $ —
Schedule of Effects of Reclassifications out of Accumulated Other Comprehensive Earnings	Amount Reclassified from Accumulated Other Comprehensive Earnings (in thousands) Component of Accumulated For the Year Ended December 31, Affected line item in the Other Comprehensive Earnings 2021 2020 2019 Consolidated Statement of Earnings Unrealized gains and losses on available-for-sale securities $ 1,859 $ 3,872 $ 3,184 Net (44 ) (369 ) — Credit losses presented within net realized gains $ 1,815 $ 3,503 $ 3,184 Earnings before income taxes (381 ) (736 ) (669 ) Income tax expense $ 1,434 $ 2,767 $ 2,515 Net earnings

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
Schedule of Net Investment Income	(in thousands) 2021 2020 2019 Interest on fixed income securities $ 60,624 $ 59,755 $ 60,364 Dividends on equity securities 11,787 9,728 9,950 Interest on cash, short-term investments and other invested assets 2,639 3,379 3,674 Gross investment income $ 75,050 $ 72,862 $ 73,988 Less investment expenses (6,188 ) (4,969 ) (5,118 ) Net investment income $ 68,862 $ 67,893 $ 68,870
Schedule of Pretax Net Realized Investment Gains (Losses) and Net Changes in Unrealized Gains (Losses) on Investments	(in thousands) 2021 2020 2019 Net realized gains (losses): Fixed income: Available-for-sale $ 1,859 $ 3,872 $ 3,184 Equity securities 62,512 15,796 14,445 Other (149 ) (1,783 ) (109 ) Total net realized gains (losses) $ 64,222 $ 17,885 $ 17,520 Net changes in unrealized gains (losses) on investments: Equity securities $ 58,459 $ 32,317 $ 78,389 Other invested assets 6,799 (216 ) (299 ) Total unrealized gains (losses) on equity securities recognized in net earnings $ 65,258 $ 32,101 $ 78,090 Fixed income: Available-for-sale $ (71,538 ) $ 67,350 $ 83,758 Investment in unconsolidated investees (3,047 ) 3,444 1,109 Other 44 369 — Total unrealized gains (losses) recognized in other comprehensive earnings $ (74,541 ) $ 71,163 $ 84,867 Net realized gains (losses) and changes in unrealized gains (losses) on investments $ 54,939 $ 121,149 $ 180,477
Schedule of Disposition of Fixed Income and Equity Securities	SALES Gross Realized Net Realized (in thousands) Proceeds Gains Losses Gain (Loss) 2021 Available-for-sale $ 65,262 $ 2,161 $ (815 ) $ 1,346 Equities 180,256 64,298 (1,786 ) 62,512 2020 Available-for-sale $ 84,697 $ 5,454 $ (1,777 ) $ 3,677 Equities 79,368 25,338 (9,542 ) 15,796 2019 Available-for-sale $ 196,799 $ 4,368 $ (2,167 ) $ 2,201 Equities 62,172 16,938 (2,493 ) 14,445 CALLS/MATURITIES Gross Realized Net Realized (in thousands) Proceeds Gains Losses Gain (Loss) 2021 Available-for-sale $ 376,751 $ 638 $ (125 ) $ 513 2020 Available-for-sale $ 283,107 $ 821 $ (27 ) $ 794 2019 Available-for-sale $ 201,698 $ 1,004 $ (21 ) $ 983
Fair Value, Assets Measured on Recurring Basis	Assets measured at fair value on a recurring basis as of December 31, 2021 and 2020, are summarized below: 2021 Quoted in Active Significant Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale U.S. government $ — $ 134,554 $ — $ 134,554 U.S. agency — 32,760 — 32,760 Non-U.S. government & agency — 8,481 — 8,481 Agency MBS — 367,187 — 367,187 ABS/CMBS/MBS* — 264,054 — 264,054 Corporate — 913,577 43,518 957,095 Municipal — 645,756 — 645,756 Total fixed income securities - available-for-sale $ — $ 2,366,369 $ 43,518 $ 2,409,887 Equity securities 613,712 64 — 613,776 Other invested assets — — — — Total $ 613,712 $ 2,366,433 $ 43,518 $ 3,023,663 2020 Quoted in Active Significant Other Significant Markets for Observable Unobservable Identical Assets Inputs Inputs (in thousands) (Level 1) (Level 2) (Level 3) Total Fixed income securities - available-for-sale U.S. government $ — $ 183,357 $ — $ 183,357 U.S. agency — 32,872 — 32,872 Non-U.S. government & agency — 10,965 — 10,965 Agency MBS — 402,071 — 402,071 ABS/CMBS/MBS* — 218,373 — 218,373 Corporate — 798,794 17,798 816,592 Municipal — 532,396 — 532,396 Total fixed income securities - available-for-sale $ — $ 2,178,828 $ 17,798 $ 2,196,626 Equity securities 523,923 83 — 524,006 Other invested assets 6,068 — — 6,068 Total $ 529,991 $ 2,178,911 $ 17,798 $ 2,726,700 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities
Summary of Changes in Balance of Level 3 Securities	(in thousands) Level 3 Securities Balance as of January 1, 2021 $ 17,798 Net realized and unrealized gains (losses) Included in net earnings as a part of: Net investment income (53 ) Net realized gains (367 ) Included in other comprehensive earnings (170 ) Total net realized and unrealized gains (losses) $ (590 ) Purchases 26,310 Balance as of December 31, 2021 $ 43,518 Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in net realized gains $ (367 ) Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in other comprehensive earnings $ (170 )
Schedule of Contractual Maturity of Securities	(in thousands) Amortized Cost Fair Value Due in one year or less $ 57,625 $ 58,134 Due after one year through five years 626,953 647,068 Due after five years through 10 years 537,777 560,653 Due after 10 years 496,778 512,791 ABS/CMBS/MBS* 627,134 631,241 Total available-for-sale $ 2,346,267 $ 2,409,887 * Asset-backed, commercial mortgage-backed and mortgage-backed securities
Schedule of Amortized Cost and Fair Value of Available-for-sale Securities	The amortized cost and fair value of available-for-sale securities at December 31, 2021 and 2020 are presented in the tables below. Amortized cost does not include the $16.4 million and $14.9 million of accrued interest receivable as of December 31, 2021 and 2020, respectively. 2021 Allowance Gross Gross Amortized for Credit Unrealized Unrealized (in thousands) Cost Losses Gains Losses Fair Value U.S. government $ 127,752 $ — $ 6,846 $ (44 ) $ 134,554 U.S. agency 30,403 — 2,374 (17 ) 32,760 Non-U.S. government & agency 8,297 — 338 (154 ) 8,481 Agency MBS 362,861 — 9,277 (4,951 ) 367,187 ABS/CMBS/MBS* 264,273 — 2,120 (2,339 ) 264,054 Corporate 925,394 (441 ) 37,247 (5,105 ) 957,095 Municipal 627,287 — 22,750 (4,281 ) 645,756 Total fixed income $ 2,346,267 $ (441 ) $ 80,952 $ (16,891 ) $ 2,409,887 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities 2020 Allowance Gross Gross Amortized for Credit Unrealized Unrealized (in thousands) Cost Losses Gains Losses Fair Value U.S. government $ 170,110 $ — $ 13,504 $ (257 ) $ 183,357 U.S. agency 28,902 — 3,970 — 32,872 Non-U.S. government & agency 10,298 — 667 — 10,965 Agency MBS 384,015 — 18,789 (733 ) 402,071 ABS/CMBS/MBS* 213,223 (17 ) 5,580 (413 ) 218,373 Corporate 753,404 (380 ) 64,501 (933 ) 816,592 Municipal 501,515 — 31,099 (218 ) 532,396 Total fixed income $ 2,061,467 $ (397 ) $ 138,110 $ (2,554 ) $ 2,196,626 * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities
Schedule of Debt Securities Available-for-sale Allowance for Credit Loss	(in thousands) 2021 2020 Beginning balance $ 397 $ — Adoption impact of ASU 2016-13 - $ 28 Increase to allowance from securities for which credit losses were not previously recorded 4 369 Reduction from securities sold during the period (4 ) - Net increase (decrease) from securities that had an allowance at the beginning of the period 44 - Ending balance $ 441 $ 397
Schedule of Securities in an Unrealized Loss Position Segregated by Type and Length of Time in an Unrealized Loss Position	December 31, 2021 December 31, 2020 12 Mos. 12 Mos. (in thousands) < 12 Mos. & Greater Total < 12 Mos. & Greater Total U.S. government Fair value $ 2,942 $ — $ 2,942 $ 5,680 $ — $ 5,680 Amortized cost 2,986 — 2,986 5,937 — 5,937 Unrealized loss $ (44 ) $ — $ (44 ) $ (257 ) $ — $ (257 ) U.S. agency Fair value $ 1,498 $ — $ 1,498 $ — $ — $ — Amortized cost 1,515 — 1,515 — — — Unrealized loss $ (17 ) $ — $ (17 ) $ — $ — $ — Non-U.S. government & agency Fair value $ 4,346 $ — $ 4,346 $ — $ — $ — Amortized cost 4,500 — 4,500 — — — Unrealized loss $ (154 ) $ — $ (154 ) $ — $ — $ — Agency MBS Fair value $ 102,145 $ 62,669 $ 164,814 $ 43,999 $ — $ 43,999 Amortized cost 104,336 65,429 169,765 44,732 — 44,732 Unrealized loss $ (2,191 ) $ (2,760 ) $ (4,951 ) $ (733 ) $ — $ (733 ) ABS/CMBS/MBS* Fair value $ 150,997 $ 3,935 $ 154,932 $ 32,771 $ 16,161 $ 48,932 Amortized cost 153,235 4,036 157,271 33,094 16,251 49,345 Unrealized loss $ (2,238 ) $ (101 ) $ (2,339 ) $ (323 ) $ (90 ) $ (413 ) Corporate Fair value $ 217,791 $ 53,818 $ 271,609 $ 52,655 $ 6,235 $ 58,890 Amortized cost 221,010 55,704 276,714 53,440 6,383 59,823 Unrealized loss $ (3,219 ) $ (1,886 ) $ (5,105 ) $ (785 ) $ (148 ) $ (933 ) Municipal Fair value $ 162,998 $ 15,037 $ 178,035 $ 25,676 $ — $ 25,676 Amortized cost 166,602 15,714 182,316 25,894 — 25,894 Unrealized loss $ (3,604 ) $ (677 ) $ (4,281 ) $ (218 ) $ — $ (218 ) Total fixed income Fair value $ 642,717 $ 135,459 $ 778,176 $ 160,781 $ 22,396 $ 183,177 Amortized cost 654,184 140,883 795,067 163,097 22,634 185,731 Unrealized loss $ (11,467 ) $ (5,424 ) $ (16,891 ) $ (2,316 ) $ (238 ) $ (2,554 ) * Non-agency asset-backed, commercial mortgage-backed and mortgage-backed securities

Policy Acquisition Costs (Table

Policy Acquisition Costs (Tables)	12 Months Ended
	Dec. 31, 2021
Deferred Policy Acquisition Costs Disclosures [Abstract]
Schedule of Policy Acquisition Costs Deferred and Amortized to Income	Policy acquisition costs deferred and amortized to income for the years ended December 31 are summarized as follows: (in thousands) 2021 2020 2019 Deferred policy acquisition costs (DAC), beginning of year $ 88,425 $ 85,044 $ 84,934 Deferred: Direct commissions $ 236,145 $ 200,917 $ 185,164 Premium taxes 17,012 14,783 14,395 Ceding commissions (47,592 ) (42,115 ) (31,140 ) Net deferred $ 205,565 $ 173,585 $ 168,419 Amortized 190,437 170,204 168,309 DAC, end of year $ 103,553 $ 88,425 $ 85,044 Policy acquisition costs: Amortized to expense - DAC $ 190,437 $ 170,204 $ 168,309 Period costs: Ceding commission - contingent (4,303 ) (4,053 ) (3,034 ) Other underwriting expenses 131,334 120,287 123,422 Total policy acquisition costs $ 317,468 $ 286,438 $ 288,697

Reinsurance (Tables)

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2021
Reinsurance Disclosures [Abstract]
Schedule of Premiums Written and Earned Along with Losses and Settlement Expenses Incurred	Premiums written and earned along with losses and settlement expenses incurred for the years ended December 31 are summarized as follows: (in thousands) 2021 2020 2019 WRITTEN Direct $ 1,313,093 $ 1,107,303 $ 1,039,955 Reinsurance assumed 34,261 29,129 25,047 Reinsurance ceded (289,821 ) (244,344 ) (204,665 ) Net $ 1,057,533 $ 892,088 $ 860,337 EARNED Direct $ 1,222,346 $ 1,062,608 $ 981,121 Reinsurance assumed 30,950 27,651 40,173 Reinsurance ceded (272,393 ) (224,512 ) (182,183 ) Net $ 980,903 $ 865,747 $ 839,111 LOSSES AND SETTLEMENT EXPENSES INCURRED Direct $ 703,903 $ 608,638 $ 521,055 Reinsurance assumed 18,087 18,783 21,951 Reinsurance ceded (265,388 ) (184,537 ) (129,590 ) Net $ 456,602 $ 442,884 $ 413,416
Schedule of Net Reinsurance Balances Recoverable, After Consideration of Collateral, from Top Reinsurers	The following table displays net reinsurance balances recoverable, after consideration of collateral, from our top reinsurers as of December 31, 2021. These reinsurers all have financial strength ratings of A or better by AM Best and S&P’s ratings services. Also shown are the amounts of written premium ceded to these reinsurers during the calendar year 2021. Net Reinsurer Ceded AM Best S&P Exposure as of Percent of Premiums Percent of (dollars in thousands) Rating Rating 12/31/2021 Total Written Total Munich Re / HSB A+, Superior AA-, Very Strong $ 102,632 14.5 % $ 34,462 11.9 % Renaissance Re A+, Superior A+, Strong 58,417 8.3 % 25,001 8.6 % Endurance Re A+, Superior A+, Strong 47,136 6.7 % 9,865 3.4 % Scor Re A+, Superior AA-, Very Strong 37,160 5.3 % 13,398 4.6 % Aspen UK Ltd. A, Excellent A-, Strong 36,164 5.1 % 9,402 3.2 % Berkley Insurance Co. A+, Superior A+, Strong 36,033 5.1 % 12,950 4.5 % Hannover Ruckversicherung A+, Superior AA-, Very Strong 33,125 4.7 % 12,942 4.5 % Safety National A++, Superior A+, Strong 32,196 4.6 % 15,544 5.4 % Nationwide Mutual A+, Superior A+, Strong 29,818 4.2 % 17,738 6.1 % Liberty Mutual A, Excellent A, Strong 23,236 3.3 % 7,240 2.5 % All other reinsurers* 270,331 38.2 % 131,279 45.3 % Total ceded exposure $ 706,248 100.0 % $ 289,821 100.0 % * All other reinsurance balances recoverable, when considered by individual reinsurer, are less than 2 percent of shareholders’ equity.

Historical Loss And LAE Devel_2

Historical Loss And LAE Development (Tables)	12 Months Ended
	Dec. 31, 2021
Historical Loss And L A E Development Disclosure [Abstract]
Schedule of Reconciliation of Unpaid Losses and Settlement Expenses (LAE)	The following table is a reconciliation of our unpaid losses and settlement expenses (LAE) for the years 2021, 2020 and 2019: (in thousands) 2021 2020 2019 Unpaid losses and LAE at beginning of year: Gross $ 1,750,049 $ 1,574,352 $ 1,461,348 Ceded (443,729 ) (384,517 ) (364,999 ) Net $ 1,306,320 $ 1,189,835 $ 1,096,349 Adoption impact of ASU 2016-13 on reinsurance balances recoverable $ — $ (1,345 ) $ — Increase (decrease) in incurred losses and LAE: Current accident year $ 582,065 $ 543,937 $ 488,700 Prior accident years (125,463 ) (101,053 ) (75,284 ) Total incurred $ 456,602 $ 442,884 $ 413,416 Loss and LAE payments for claims incurred: Current accident year $ (101,590 ) $ (93,077 ) $ (80,055 ) Prior accident year (225,863 ) (231,977 ) (239,875 ) Total paid $ (327,453 ) $ (325,054 ) $ (319,930 ) Net unpaid losses and LAE at end of year $ 1,435,469 $ 1,306,320 $ 1,189,835 Unpaid losses and LAE at end of year: Gross $ 2,043,555 $ 1,750,049 $ 1,574,352 Ceded (608,086 ) (443,729 ) (384,517 ) Net $ 1,435,469 $ 1,306,320 $ 1,189,835
Schedule of Incurred and Paid Claims Development	Casualty - Primary Occurrence (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 91,807 $ 78,406 $ 65,893 $ 61,072 $ 59,028 $ 59,488 $ 60,328 $ 60,465 $ 60,591 $ 60,155 $ 1,589 5,192 2013 80,823 67,297 62,882 60,329 60,162 59,556 59,116 57,106 57,519 2,096 4,324 2014 88,092 79,497 71,592 67,237 66,389 66,702 65,636 63,727 3,034 4,295 2015 94,835 84,975 83,579 78,675 76,398 75,470 75,438 6,644 4,406 2016 101,950 96,753 90,611 85,449 83,374 79,440 10,352 4,315 2017 119,741 111,391 102,583 95,513 90,759 15,999 4,491 2018 141,513 130,281 125,731 115,076 32,268 4,822 2019 146,011 135,209 120,570 62,738 5,175 2020 145,171 137,439 88,880 4,394 2021 142,797 112,702 3,678 Total $ 942,920 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 5,897 $ 14,539 $ 23,889 $ 33,822 $ 43,276 $ 47,970 $ 51,611 $ 54,391 $ 55,679 $ 56,660 2013 6,334 13,021 22,366 34,786 40,609 45,753 47,783 49,411 50,597 2014 11,436 18,771 29,545 40,270 47,343 52,387 55,965 56,784 2015 10,157 19,902 33,020 45,056 54,270 58,866 62,997 2016 10,142 24,186 35,764 48,042 56,152 60,349 2017 13,154 25,933 38,783 52,823 62,236 2018 15,066 32,365 48,424 63,980 2019 15,698 30,673 41,911 2020 17,096 30,596 2021 14,428 * Presented as unaudited required supplementary information. Total $ 500,538 All outstanding liabilities before 2012, net of reinsurance 10,760 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 453,142 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 12.8 % 13.3 % 14.8 % 16.5 % 11.6 % 7.2 % 5.2 % 2.9 % 2.1 % 1.6 % Casualty - Excess Occurrence (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 29,042 $ 21,558 $ 21,021 $ 21,885 $ 21,231 $ 22,433 $ 23,020 $ 25,286 $ 26,129 $ 26,848 $ 783 867 2013 39,984 34,824 26,857 25,425 25,599 24,922 25,496 25,073 24,836 1,396 949 2014 50,889 39,095 35,119 32,274 33,372 33,458 35,128 35,683 2,622 923 2015 53,672 50,857 47,392 42,840 43,328 42,446 41,690 5,439 699 2016 56,341 49,385 37,676 33,125 30,251 29,671 11,023 646 2017 62,863 55,868 48,363 44,737 43,249 16,698 631 2018 69,362 62,646 54,626 51,023 26,824 590 2019 88,078 89,691 79,083 47,276 603 2020 107,579 98,409 74,182 471 2021 136,433 93,982 371 Total $ 566,925 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 1,315 $ 3,573 $ 8,843 $ 15,380 $ 16,879 $ 17,747 $ 19,310 $ 21,993 $ 22,202 $ 22,246 2013 1,060 5,701 10,967 14,545 16,967 17,956 18,524 21,229 22,154 2014 1,899 4,006 11,002 18,852 22,541 23,376 26,068 28,963 2015 2,048 10,127 19,571 23,184 28,756 31,352 32,752 2016 1,068 3,396 7,441 10,054 12,703 14,400 2017 17 5,679 9,275 15,441 18,470 2018 2,506 5,823 10,801 17,294 2019 4,213 19,044 25,389 2020 2,901 13,856 2021 5,317 * Presented as unaudited required supplementary information. Total $ 200,841 All outstanding liabilities before 2012, net of reinsurance 18,495 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 384,579 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 4.0 % 12.2 % 15.4 % 15.0 % 9.2 % 4.3 % 4.8 % 9.7 % 2.3 % 0.2 % Casualty - Claims Made (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 27,576 $ 26,144 $ 20,727 $ 19,590 $ 18,022 $ 17,612 $ 17,569 $ 20,785 $ 22,325 $ 22,236 $ 207 804 2013 40,095 41,488 44,054 40,288 38,473 37,959 38,352 37,974 37,950 767 1,042 2014 53,929 55,386 58,152 55,350 51,554 53,841 53,783 52,619 1,504 1,305 2015 55,006 47,831 42,206 39,906 39,653 39,619 38,609 2,759 1,338 2016 59,992 67,760 69,493 67,728 64,730 65,078 4,808 1,507 2017 60,572 62,450 62,714 57,450 59,907 9,039 1,648 2018 66,128 62,416 56,468 48,457 17,399 1,391 2019 62,918 61,712 52,224 26,387 1,508 2020 60,278 56,785 43,408 1,287 2021 51,219 42,451 1,112 Total $ 485,084 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 433 $ 4,086 $ 6,898 $ 9,218 $ 10,968 $ 14,378 $ 15,621 $ 16,450 $ 16,892 $ 17,148 2013 792 7,073 18,425 26,121 29,678 32,789 34,535 35,476 36,078 2014 1,705 9,775 27,923 35,755 40,080 44,127 46,122 50,714 2015 2,215 10,738 16,774 20,920 28,795 32,241 33,529 2016 2,060 14,558 27,465 39,370 47,999 52,846 2017 2,455 11,350 22,728 36,522 42,918 2018 1,964 11,965 18,840 24,918 2019 1,839 8,123 14,117 2020 1,488 5,687 2021 999 * Presented as unaudited required supplementary information. Total $ 278,954 All outstanding liabilities before 2012, net of reinsurance 3,575 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 209,705 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 3.2 % 16.1 % 19.6 % 15.7 % 11.6 % 9.5 % 4.3 % 5.0 % 1.8 % 1.2 % Casualty - Transportation (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 21,452 $ 22,203 $ 22,924 $ 23,511 $ 23,689 $ 23,620 $ 23,305 $ 23,731 $ 23,845 $ 23,955 $ 74 2,287 2013 32,742 32,853 32,989 37,673 38,811 39,974 39,309 39,183 39,586 118 2,853 2014 38,361 33,015 36,452 38,590 40,202 40,508 41,156 41,974 297 3,099 2015 38,561 46,258 47,021 46,395 45,162 45,525 45,807 708 3,186 2016 50,430 53,519 54,105 52,277 52,818 53,915 1,235 3,943 2017 55,640 53,641 45,017 43,764 45,351 2,257 3,639 2018 57,597 54,592 38,719 36,468 4,946 3,402 2019 58,297 56,129 43,976 9,024 3,313 2020 43,573 35,524 16,243 1,637 2021 51,322 9,745 2,161 Total $ 417,878 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 4,466 $ 8,533 $ 12,394 $ 17,318 $ 20,931 $ 22,566 $ 22,730 $ 23,180 $ 23,181 $ 23,181 2013 5,306 11,978 19,761 28,220 33,480 35,923 37,327 37,915 38,172 2014 7,125 13,933 19,676 27,457 33,190 38,282 40,006 40,427 2015 6,984 20,709 29,554 37,222 39,339 41,345 42,626 2016 8,923 18,354 30,354 38,001 43,564 47,488 2017 7,979 17,070 24,090 30,260 36,141 2018 6,980 12,827 19,216 24,503 2019 7,148 15,852 21,120 2020 3,986 7,876 2021 5,341 * Presented as unaudited required supplementary information. Total $ 286,875 All outstanding liabilities before 2012, net of reinsurance 528 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 131,531 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 15.5 % 18.3 % 17.0 % 17.1 % 11.7 % 7.4 % 2.8 % 1.5 % 0.3 % 0.0 % Property (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 85,485 $ 80,155 $ 79,181 $ 77,569 $ 79,175 $ 78,125 $ 78,161 $ 78,002 $ 77,924 $ 77,883 $ 7 2,640 2013 63,864 62,090 62,173 62,114 61,914 61,834 61,776 61,623 61,400 36 2,996 2014 56,587 49,441 48,801 48,761 49,217 49,444 49,479 49,520 52 4,562 2015 59,863 56,103 53,958 52,720 53,111 52,781 52,878 96 4,075 2016 62,900 55,594 55,384 55,930 55,424 55,383 177 3,377 2017 90,803 83,273 84,961 82,671 82,319 1,321 2,893 2018 89,091 83,457 79,961 80,470 3,642 2,337 2019 71,232 65,189 61,116 3,193 2,446 2020 118,247 110,466 17,071 2,837 2021 135,447 45,890 2,616 Total $ 766,882 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 39,074 $ 66,509 $ 72,057 $ 73,705 $ 75,640 $ 76,152 $ 77,159 $ 77,323 $ 77,347 $ 77,360 2013 32,208 50,840 57,407 59,259 60,520 61,195 61,325 61,335 61,188 2014 30,550 43,380 46,148 46,528 47,799 49,027 49,259 49,317 2015 32,184 49,348 50,197 51,290 52,078 52,342 52,400 2016 33,134 46,921 51,371 53,006 54,328 54,747 2017 41,314 66,818 74,415 78,360 80,581 2018 37,048 68,264 72,357 75,253 2019 30,703 51,740 55,092 2020 43,192 79,660 2021 57,272 * Presented as unaudited required supplementary information. Total $ 642,870 All outstanding liabilities before 2012, net of reinsurance 640 Liabilities for losses and loss adjustment expenses, net of reinsurance $ 124,652 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 51.3 % 31.8 % 6.6 % 2.8 % 2.3 % 1.1 % 0.5 % 0.1 % -0.1 % 0.0 % Surety (in thousands, except number of claims) Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance As of December 31, 2021 For the Years Ended December 31, Cumulative Number of Reported AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 Total IBNR Claims 2012 $ 17,114 $ 11,452 $ 8,667 $ 8,180 $ 7,867 $ 7,471 $ 7,099 $ 7,082 $ 6,985 $ 7,131 $ 2 1,480 2013 16,080 7,516 6,170 5,399 5,271 5,231 5,209 5,107 5,046 10 1,409 2014 16,450 8,106 5,225 4,427 4,267 4,319 4,266 4,227 8 1,355 2015 16,958 12,957 11,113 10,456 9,792 9,521 9,275 59 1,242 2016 18,928 11,062 9,351 8,895 8,391 7,948 125 1,381 2017 16,127 8,641 8,798 8,116 8,034 306 1,790 2018 16,765 7,227 4,564 3,947 713 1,323 2019 14,785 7,205 5,053 2,047 1,112 2020 19,241 14,840 7,212 748 2021 18,540 15,647 444 Total $ 84,041 Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance For the Years Ended December 31, AY 2012* 2013* 2014* 2015* 2016* 2017* 2018* 2019* 2020* 2021 2012 $ 1,883 $ 6,680 $ 6,726 $ 7,416 $ 7,536 $ 7,406 $ 7,065 $ 6,996 $ 6,941 $ 7,083 2013 1,116 2,856 4,701 4,911 5,098 5,150 5,128 5,061 5,029 2014 722 4,283 4,166 4,059 4,131 4,234 4,214 4,197 2015 3,192 6,719 7,695 9,436 9,183 9,186 9,168 2016 3,087 5,817 6,299 7,640 8,086 7,673 2017 979 2,862 7,062 7,221 7,362 2018 1,835 2,588 2,368 2,536 2019 336 2,433 2,765 2020 835 2,719 2021 1,197 * Presented as unaudited required supplementary information. Total $ 49,729 All outstanding liabilities before 2012, net of reinsurance (68 ) Liabilities for losses and loss adjustment expenses, net of reinsurance $ 34,244 Average Annual Percentage Payout of Incurred Losses by Age, Net of Reinsurance* Years 1 2 3 4 5 6 7 8 9 10 21.6 % 39.5 % 13.0 % 7.6 % 2.0 % -0.7 % -1.5 % -0.9 % -0.7 % 2.0 %
Schedule of Reconciliation of the Net Incurred and Paid Loss Development Tables to the Liability for Unpaid Losses and Settlement Expenses in the Consolidated Balance Sheet	The following is a reconciliation of the net incurred and paid loss development tables to the liability for unpaid losses and settlement expenses in the consolidated balance sheet: (in thousands) December 31, 2021 December 31, 2020 Net outstanding liabilities: Casualty - Primary Occurrence $ 453,142 $ 432,823 Casualty - Excess Occurrence 384,579 312,827 Casualty - Claims Made 209,705 214,103 Casualty - Transportation 131,531 129,852 Property 124,652 103,383 Surety 34,244 27,009 Unallocated loss adjustment expenses 59,391 54,954 Allowance for uncollectible reinsurance balances recoverable on unpaid losses and settlement expenses 11,188 8,634 Other 27,037 22,735 Liabilities for unpaid loss and settlement expenses, net of reinsurance $ 1,435,469 $ 1,306,320 Reinsurance recoverable on unpaid claims: Casualty - Primary Occurrence $ 43,688 $ 35,202 Casualty - Excess Occurrence 122,092 88,528 Casualty - Claims Made 271,259 223,020 Casualty - Transportation 66,283 53,251 Property 65,098 40,257 Surety 50,743 4,017 Allowance for uncollectible reinsurance balances recoverable on unpaid losses and settlement expenses (11,188 ) (8,634 ) Other 111 8,088 Total reinsurance balances recoverable on unpaid losses and settlement expenses $ 608,086 $ 443,729 Total gross liability for unpaid loss and settlement expenses $ 2,043,555 $ 1,750,049
Schedule of Prior Accident Years' Loss Reserve Development by Segment	The following table summarizes our prior accident years’ loss reserve development by segment for 2021, 2020 and 2019: (in thousands) 2021 2020 2019 Casualty $ (108,632 ) $ (75,075 ) $ (62,497 ) Property (10,981 ) (13,019 ) (4,461 ) Surety (5,850 ) (12,959 ) (8,326 ) Total $ (125,463 ) $ (101,053 ) $ (75,284 )
Schedule of Paid and Unpaid Environmental, Asbestos and Mass Tort Claims Data (Including Incurred but not Reported Losses)	The following table represents paid and unpaid environmental, asbestos and mass tort claims data (including incurred but not reported losses) as of December 31, 2021, 2020 and 2019: (in thousands) 2021 2020 2019 Loss and LAE Payments (Cumulative): Gross $ 141,768 $ 139,804 $ 137,485 Ceded (69,576 ) (69,219 ) (68,849 ) Net $ 72,192 $ 70,585 $ 68,636 Unpaid Losses and LAE at End of Year: Gross $ 25,747 $ 22,485 $ 22,616 Ceded (5,718 ) (4,619 ) (5,149 ) Net $ 20,029 $ 17,866 $ 17,467

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Deferred Tax Assets and Deferred Tax Liabilities	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are summarized below. (in thousands) 2021 2020 Deferred tax assets: Tax discounting of unpaid losses and settlement expenses $ 22,637 $ 21,096 Unearned premium offset 23,080 19,862 Deferred compensation 3,469 2,829 Stock option expense 3,089 2,749 Lease liability 3,796 3,971 Other 367 389 Deferred tax assets before allowance $ 56,438 $ 50,896 Less valuation allowance — — Total deferred tax assets $ 56,438 $ 50,896 Deferred tax liabilities: Net unrealized appreciation of securities $ 76,533 $ 77,639 Deferred policy acquisition costs 21,746 18,569 Lease asset 3,101 3,402 Discounting of unpaid losses and settlement expenses - Tax Cuts and Jobs Act (TCJA) implementation offset 2,545 3,181 Fixed assets 3,518 3,439 Intangible assets 1,537 1,558 Undistributed earnings of unconsolidated investees 29,515 21,813 Other 1,452 1,530 Total deferred tax liabilities $ 139,947 $ 131,131 Net deferred tax liability $ (83,509 ) $ (80,235 )
Schedule of Reconciliation of Income Tax Expense (Benefit) Attributable to Income from Operations with Amounts Computed by Applying U.S. Federal Tax Rate to Pretax Income from Continuing Operations	Income tax expense (benefit) attributable to income from operations for the years ended December 31, 2021, 2020 and 2019, differed from the amounts computed by applying the U.S. federal tax rate of 21 percent to pretax income from continuing operations as demonstrated in the following table: (in thousands) 2021 2020 2019 Provision for income taxes at the statutory federal tax rates $ 72,307 21.0 % $ 39,867 21.0 % $ 48,874 21.0 % Increase (reduction) in taxes resulting from: Excess tax benefit on share-based compensation (3,090 ) (0.9 ) % (3,537 ) (1.8 ) % (3,958 ) (1.7 ) % Tax-exempt interest income (1,219 ) (0.3 ) % (1,293 ) (0.7 ) % (1,238 ) (0.5 ) % Dividends received deduction (891 ) (0.3 ) % (883 ) (0.5 ) % (823 ) (0.4 ) % Investment tax credit (3,491 ) (1.0 ) % (2,435 ) (1.3 ) % — — % ESOP dividends paid deduction (1,566 ) (0.5 ) % (1,083 ) (0.6 ) % (1,122 ) (0.5 ) % Unconsolidated investee dividends — — % (479 ) (0.2 ) % (1,802 ) (0.8 ) % Nondeductible expenses 3,834 1.1 % 1,878 1.0 % 1,649 0.7 % Other items, net (917 ) (0.2 ) % 715 0.4 % (488 ) (0.1 ) % Total $ 64,967 18.9 % $ 32,750 17.3 % $ 41,092 17.7 %

Employee Benefits (Tables)

Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2021
Compensation And Retirement Disclosure [Abstract]
Summary of Option Activity	The following table summarize option activity in 2021: Weighted Aggregate Weighted Average Intrinsic Average Remaining Value Options Exercise Price Contractual Life (in 000’s) Outstanding as of January 1, 2021 1,632,334 $ 70.67 Granted 260,271 109.67 Exercised (215,065 ) 55.50 Cancelled or forfeited (8,215 ) 84.29 Outstanding as of December 31, 2021 1,669,325 $ 78.63 4.90 $ 56,018 Exercisable at December 31, 2021 784,768 $ 67.14 3.66 $ 35,282
Summary of Weighted Average Grant-date Assumptions and Weighted Average Fair Values	The fair value of options were estimated using a Black-Scholes based option pricing model with the following weighted-average grant-date assumptions and weighted-average fair values as of December 31: 2021 2020 2019 Weighted-average fair value of grants $ 17.11 $ 13.24 $ 13.49 Risk-free interest rates 0.75 % 0.39 % 2.26 % Dividend yield 2.06 % 2.30 % 2.69 % Expected volatility 22.73 % 22.67 % 22.71 % Expected option life 4.97 years 4.96 years 4.96 years
Schedule of Restricted Stock Units Activity	Weighted Average Grant Date RSUs Fair Value Nonvested at January 1, 2021 47,658 $ 81.53 Granted 16,780 113.02 Reinvested 1,233 108.00 Vested (19,725 ) 72.53 Forfeited (878 ) 94.28 Nonvested at December 31, 2021 45,068 $ 97.67

Statutory Information and Div_2

Statutory Information and Dividend Restrictions (Tables)	12 Months Ended
	Dec. 31, 2021
Statutory Information And Dividend Restrictions Disclosure [Abstract]
Schedule of Selected Information for Insurance Subsidiaries	(in thousands) 2021 2020 2019 Consolidated net income, statutory basis $ 207,550 $ 120,329 $ 129,625 Consolidated surplus, statutory basis $ 1,240,649 $ 1,121,592 $ 1,029,671

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Schedule of Components of Lease Expense and Other lease Information	The components of lease expense and other lease information as of and during the years ended December 31, 2021, 2020 and 2019 are as follows: (in thousands) 2021 2020 2019 Operating lease cost $ 5,131 $ 5,504 $ 5,772 Variable lease cost 1,433 1,346 1,850 Sublease income (508 ) (262 ) — Total lease cost $ 6,056 $ 6,588 $ 7,622 Cash paid for amounts included in measurement of lease liabilities Operating cash flows from operating leases $ 5,738 $ 5,963 $ 5,711 ROU assets obtained in exchange for new operating lease liabilities $ 4,828 $ 81 $ 1,388 Reduction to ROU assets resulting from reduction to lease liabilities $ 1,042 $ 18 $ 1,279 Other non-cash reductions to ROU assets $ 48 $ 1,192 $ — (in thousands) 2021 2020 Operating lease ROU assets $ 14,765 $ 16,200 Operating lease liabilities $ 16,905 $ 19,072 Weighted-average remaining lease term - operating leases 4.52 years 3.87 years Weighted-average discount rate - operating leases 2.02 % 2.32 %
Schedule of Future Minimum Lease Payments under Non-cancellable Leases	Future minimum lease payments under non-cancellable leases as of December 31, 2021 were as follows: (in thousands) 2021 2022 $ 5,353 2023 4,826 2024 2,844 2025 1,481 2026 884 Thereafter 2,283 Total future minimum lease payments $ 17,671 Less imputed interest (766 ) Total operating lease liability $ 16,905

Operating Segment Information (

Operating Segment Information (Tables)	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Summary of Selected Information by Operating Segment	REVENUES (in thousands) 2021 2020 2019 Casualty $ 633,639 $ 569,521 $ 558,458 Property 231,837 183,720 164,022 Surety 115,427 112,506 116,631 Net premiums earned $ 980,903 $ 865,747 $ 839,111 Net investment income 68,862 67,893 68,870 Net realized gains 64,222 17,885 17,520 Net unrealized gains on equity securities 65,258 32,101 78,090 Total $ 1,179,245 $ 983,626 $ 1,003,591 INSURANCE EXPENSES (in thousands) 2021 2020 2019 Loss and settlement expenses: Casualty $ 311,627 $ 322,099 $ 330,156 Property 129,924 111,356 73,614 Surety 15,051 9,429 9,646 Total loss and settlement expenses $ 456,602 $ 442,884 $ 413,416 Policy acquisition costs: Casualty $ 179,354 $ 162,058 $ 166,499 Property 72,008 59,926 55,986 Surety 66,106 64,454 66,212 Total policy acquisition costs $ 317,468 $ 286,438 $ 288,697 Other insurance expenses: Casualty $ 47,139 $ 40,937 $ 41,202 Property 18,605 15,620 16,279 Surety 11,163 10,271 11,949 Total other insurance expenses $ 76,907 $ 66,828 $ 69,430 Total $ 850,977 $ 796,150 $ 771,543 NET EARNINGS (in thousands) 2021 2020 2019 Casualty $ 95,519 $ 44,427 $ 20,601 Property 11,300 (3,182 ) 18,143 Surety 23,107 28,352 28,824 Net underwriting income $ 129,926 $ 69,597 $ 67,568 Net investment income 68,862 67,893 68,870 Net realized gains 64,222 17,885 17,520 Net unrealized gains on equity securities 65,258 32,101 78,090 Interest on debt (7,677 ) (7,603 ) (7,588 ) General corporate expense (13,330 ) (10,265 ) (12,686 ) Equity in earnings of unconsolidated investees 37,060 20,233 20,960 Total earnings before incomes taxes $ 344,321 $ 189,841 $ 232,734 Income tax expense 64,967 32,750 41,092 Net earnings $ 279,354 $ 157,091 $ 191,642
Summary of Revenue by Major Product Type	The following table further summarizes revenues by major product type within each segment: NET PREMIUMS EARNED Year ended December 31, (in thousands) 2021 2020 2019 CASUALTY Commercial excess and personal umbrella $ 219,437 $ 178,214 $ 140,483 General liability 90,853 91,653 98,880 Professional services 88,855 85,196 81,329 Commercial transportation 83,352 64,624 83,213 Small commercial 64,660 63,357 55,701 Executive products 21,873 26,509 27,088 Other casualty 64,609 59,968 71,764 Total $ 633,639 $ 569,521 $ 558,458 PROPERTY Commercial property $ 107,941 $ 79,406 $ 68,310 Marine 97,745 81,852 74,887 Specialty personal 21,385 19,596 19,316 Other property 4,766 2,866 1,509 Total $ 231,837 $ 183,720 $ 164,022 SURETY Miscellaneous $ 43,982 $ 42,292 $ 44,721 Commercial 43,738 42,872 43,553 Contract 27,707 27,342 28,357 Total $ 115,427 $ 112,506 $ 116,631 Grand total $ 980,903 $ 865,747 $ 839,111

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Description of Business - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021companystate
DESCRIPTION OF BUSINESS
Number of insurance companies through which the entity conducts operations | company	3
RLI Ins.
DESCRIPTION OF BUSINESS
Number of states in which entity operates	50
Mt. Hawley Insurance Company
DESCRIPTION OF BUSINESS
Number of states in which entity operates	50
Contractors Bonding and Insurance Company
DESCRIPTION OF BUSINESS
Number of states in which entity operates	50

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Property and Equipment - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021
Equipment | Maximum
PROPERTY AND EQUIPMENT
Useful life	10 years
Equipment | Minimum
PROPERTY AND EQUIPMENT
Useful life	3 years
Buildings and improvements | Maximum
PROPERTY AND EQUIPMENT
Useful life	30 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Investment in Unconsolidated Investees (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)Item	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investment amount	$ 171,311	$ 128,382
Investee earnings recorded in income	37,060	20,233	$ 20,960
Reinsurance assumed	34,261	29,129	25,047
Net premiums earned	980,903	865,747	839,111
Undistributed earnings from equity method investees included in retained earnings	145,800
Dividends received		4,675	13,200
Investments in Unconsolidated Investees
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Investee earnings recorded in income	$ 125,300	70,400	77,300
Maui Jim Inc.
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)	40.00%
Investment amount	$ 113,100	90,900
Investee earnings recorded in income	$ 22,800	10,400	13,600
Dividends received			13,200
Prime Holdings Insurance Services, Inc. (Prime)
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Equity ownership interest (as a percent)	23.00%
Investment amount	$ 47,200	32,700
Investee earnings recorded in income	$ 17,000	10,800	7,400
Number of insurance carriers Company writes through | Item	2
Reinsurance assumed	$ 22,200	15,700	13,100
Net premiums earned	$ 19,100	14,300	$ 28,700
Dividends received		$ 4,700

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Schedule of Summarized Financial Information of Equity Method Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Total assets	$ 4,508,302	$ 3,938,485
Total liabilities	3,278,941	2,802,507
Total equity	1,229,361	1,135,978	$ 995,388	$ 806,842
Investments in Unconsolidated Investees
INVESTMENT IN UNCONSOLIDATED INVESTEES:
Total assets	1,172,600	837,200
Total liabilities	687,800	473,200
Total equity	$ 484,800	$ 364,000

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Goodwill and Intangible Assets - Schedule of Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill	$ 46,062	$ 46,062
State insurance licenses	7,500	7,500
Definite-lived intangibles, net of accumulated amortization of $4,035 at 12/31/21 and $3,878 at 12/31/20		157
Total intangibles	7,500	7,657
Total goodwill and intangibles	53,562	53,719
Surety
Business Acquisition [Line Items]
Goodwill	40,816	40,816
Casualty
Business Acquisition [Line Items]
Goodwill	$ 5,246	$ 5,246

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Goodwill and Intangible Assets - Schedule of Goodwill and Intangible Assets (Parenthetical) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Accumulated amortization of definite-lived intangibles	$ 4,035	$ 3,878

Summary of Significant Accou_10

Summary of Significant Accounting Policies - Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Amortization of intangible assets	$ 0.2	$ 0.4	$ 0.4

Summary of Significant Accou_11

Summary of Significant Accounting Policies - Schedule of Reconciliation of Numerator and Denominator of the Basic and Diluted Earnings Per Share Computations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic EPS, Income (Numerator)
Income available to common shareholders	$ 279,354	$ 157,091	$ 191,642
Diluted EPS, Income (Numerator)
Income available to common shareholders and assumed conversions	$ 279,354	$ 157,091	$ 191,642
Basic EPS, Weighted Average Shares (Denominator)
Number of shares outstanding	45,230	45,000	44,734
Effect of Dilutive Securities, Shares (Denominator)
Stock options	482	376	523
Diluted EPS, Weighted Average Shares (Denominator)
Number of shares outstanding	45,712	45,376	45,257
Earnings Per Share, Diluted, Other Disclosures
Anti-dilutive options excluded from diluted EPS	214	384	65
Basic EPS, Per Share Amount
Basic net earnings per share (in dollars per share)	$ 6.18	$ 3.49	$ 4.28
Diluted EPS, Per Share Amount
Diluted earnings per share (in dollars per share)	$ 6.11	$ 3.46	$ 4.23

Summary of Significant Accou_12

Summary of Significant Accounting Policies - Comprehensive Earnings - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2020
COMPREHENSIVE EARNINGS
Tax rate used (as a percent)	21.00%	21.00%	21.00%
Other comprehensive income (loss), tax	$ (15,700)	$ 14,900	$ 17,800
Accumulated other comprehensive earnings	$ 49,826	$ 108,714
Cumulative Effect, Period of Adoption, Adjustment | ASU 2016-13 | Maximum
COMPREHENSIVE EARNINGS
Accumulated other comprehensive earnings				$ (100)

Summary of Significant Accou_13

Summary of Significant Accounting Policies - Schedule of Changes in the Balance of Each Component of Accumulated Other Comprehensive Earnings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance	$ 108,714
Net current period other comprehensive earnings (loss)	(58,888)	$ 56,219	$ 67,045
Ending balance	49,826	108,714
Balance of securities for which an allowance for credit losses has not been recognized in net earnings	124	470
Unrealized Gains and Losses on Available-for-Sale Securities
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance	108,714	52,473	(14,572)
Other comprehensive earnings before reclassifications	(57,454)	58,986	69,560
Amounts reclassified from accumulated other comprehensive earnings	(1,434)	(2,767)	(2,515)
Ending balance	49,826	108,714	52,473
Unrealized Gains and Losses on Available-for-Sale Securities | Cumulative Effect, Period of Adoption, Adjustment | ASU 2016-13
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance		22
Ending balance			22
Unrealized Gains and Losses on Available-for-Sale Securities | Cumulative Effect, Period of Adoption, Adjusted Balance
Changes in the balance of each component of accumulated other comprehensive earnings
Beginning balance	$ 108,714	52,495	(14,572)
Ending balance		$ 108,714	$ 52,495

Summary of Significant Accou_14

Summary of Significant Accounting Policies - Schedule of Effects of Reclassifications out of Accumulated Other Comprehensive Earnings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reclassification Adjustment Out of Accumulated Other Comprehensive Income
Net realized gains	$ 64,222	$ 17,885	$ 17,520
Earnings before income taxes	344,321	189,841	232,734
Income tax expense	(64,967)	(32,750)	(41,092)
Net earnings	279,354	157,091	191,642
Unrealized Gains and Losses on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out of Accumulated Other Comprehensive Income
Net realized gains	1,859	3,872	3,184
Credit losses presented within net realized gains	(44)	(369)
Earnings before income taxes	1,815	3,503	3,184
Income tax expense	(381)	(736)	(669)
Net earnings	$ 1,434	$ 2,767	$ 2,515

Summary of Significant Accou_15

Summary of Significant Accounting Policies - Insurance Risk - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Unpaid losses and settlement expenses	$ 2,043,555	$ 1,750,049	$ 1,574,352	$ 1,461,348

Summary of Significant Accou_16

Summary of Significant Accounting Policies - Catastrophe Exposures - Additional Information (Details) - USD ($) $ in Millions	Jan. 01, 2022	Dec. 31, 2021
California Earthquake
Liability For Catastrophe Claims [Line Items]
Catastrophe reinsurance		$ 500
First-dollar retention		25
California Earthquake | Subsequent Event
Liability For Catastrophe Claims [Line Items]
Catastrophe reinsurance	$ 600
First-dollar retention	25
Non-California Earthquake
Liability For Catastrophe Claims [Line Items]
Catastrophe reinsurance		525
First-dollar retention		25
Non-California Earthquake | Subsequent Event
Liability For Catastrophe Claims [Line Items]
Catastrophe reinsurance	625
First-dollar retention	25
Earthquake
Liability For Catastrophe Claims [Line Items]
First-dollar retention		25
Earthquake | Subsequent Event
Liability For Catastrophe Claims [Line Items]
First-dollar retention	25
Other Perils
Liability For Catastrophe Claims [Line Items]
Catastrophe reinsurance		375
First-dollar retention		$ 25
Other Perils | Subsequent Event
Liability For Catastrophe Claims [Line Items]
Catastrophe reinsurance	475
First-dollar retention	$ 25

Investments - Net Investment In

Investments - Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	$ 75,050	$ 72,862	$ 73,988
Less investment expenses	(6,188)	(4,969)	(5,118)
Net investment income	68,862	67,893	68,870
Debt Securities
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	60,624	59,755	60,364
Equity Securities
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	11,787	9,728	9,950
Cash and Short-term Investments
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	$ 2,639	$ 3,379	$ 3,674

Investments - Schedule of Preta

Investments - Schedule of Pretax Net Realized Investment Gains (Losses) and Net Changes in Unrealized Gains (Losses) on Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investment1 [Line Items]
Net realized gains (losses)	$ 64,222	$ 17,885	$ 17,520
Net unrealized gains (losses) on equity securities	65,258	32,101	78,090
Net changes in unrealized gains (losses) on investments:	(74,541)	71,163	84,867
Net realized gains (losses) and changes in unrealized gains (losses) on investments	54,939	121,149	180,477
Debt Securities | Available for sale securities
Investment1 [Line Items]
Net realized gains (losses)	1,859	3,872	3,184
Net changes in unrealized gains (losses) on investments:	(71,538)	67,350	83,758
Equity Securities
Investment1 [Line Items]
Net realized gains (losses)	62,512	15,796	14,445
Net unrealized gains (losses) on equity securities	58,459	32,317	78,389
Other
Investment1 [Line Items]
Net realized gains (losses)	(149)	(1,783)	(109)
Net unrealized gains (losses) on equity securities	6,799	(216)	(299)
Net changes in unrealized gains (losses) on investments:	44	369
Equity Method Investments
Investment1 [Line Items]
Net changes in unrealized gains (losses) on investments:	$ (3,047)	$ 3,444	$ 1,109

Investments - Disposition of Fi

Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SALES | Debt Securities | Available for sale securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	$ 65,262	$ 84,697	$ 196,799
Gross Realized Gains	2,161	5,454	4,368
Gross Realized Losses	(815)	(1,777)	(2,167)
Net Realized Gain (Loss)	1,346	3,677	2,201
SALES | Equity Securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	180,256	79,368	62,172
Gross Realized Gains	64,298	25,338	16,938
Gross Realized Losses	(1,786)	(9,542)	(2,493)
Net Realized Gain (Loss)	62,512	15,796	14,445
CALLS/MATURITIES | Debt Securities | Available for sale securities
Summary of the disposition of fixed income and equity securities
Proceeds From Sales	376,751	283,107	201,698
Gross Realized Gains	638	821	1,004
Gross Realized Losses	(125)	(27)	(21)
Net Realized Gain (Loss)	$ 513	$ 794	$ 983

Investments - Assets Measured a

Investments - Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets measured at Fair Value
Available-for-sale fixed income	$ 2,409,887	$ 2,196,626
Equity securities	613,776	524,006
Municipal
Assets measured at Fair Value
Available-for-sale fixed income	645,756	532,396
Fair Value Measured on Recurring Basis
Assets measured at Fair Value
Available-for-sale fixed income	2,409,887	2,196,626
Equity securities	613,776	524,006
Other invested assets		6,068
Total assets at fair value	3,023,663	2,726,700
Fair Value Measured on Recurring Basis | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets measured at Fair Value
Equity securities	613,712	523,923
Other invested assets		6,068
Total assets at fair value	613,712	529,991
Fair Value Measured on Recurring Basis | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	2,366,369	2,178,828
Equity securities	64	83
Total assets at fair value	2,366,433	2,178,911
Fair Value Measured on Recurring Basis | Significant Unobservable Inputs (Level 3)
Assets measured at Fair Value
Available-for-sale fixed income	43,518	17,798
Total assets at fair value	43,518	17,798
Fair Value Measured on Recurring Basis | U.S. government
Assets measured at Fair Value
Available-for-sale fixed income	134,554	183,357
Fair Value Measured on Recurring Basis | U.S. government | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	134,554	183,357
Fair Value Measured on Recurring Basis | U.S. Agency
Assets measured at Fair Value
Available-for-sale fixed income	32,760	32,872
Fair Value Measured on Recurring Basis | U.S. Agency | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	32,760	32,872
Fair Value Measured on Recurring Basis | Non-U.S. govt. & agency
Assets measured at Fair Value
Available-for-sale fixed income	8,481	10,965
Fair Value Measured on Recurring Basis | Non-U.S. govt. & agency | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	8,481	10,965
Fair Value Measured on Recurring Basis | Agency MBS
Assets measured at Fair Value
Available-for-sale fixed income	367,187	402,071
Fair Value Measured on Recurring Basis | Agency MBS | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	367,187	402,071
Fair Value Measured on Recurring Basis | ABS/CMBS/MBS
Assets measured at Fair Value
Available-for-sale fixed income	264,054	218,373
Fair Value Measured on Recurring Basis | ABS/CMBS/MBS | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	264,054	218,373
Fair Value Measured on Recurring Basis | Corporate Debt
Assets measured at Fair Value
Available-for-sale fixed income	957,095	816,592
Fair Value Measured on Recurring Basis | Corporate Debt | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	913,577	798,794
Fair Value Measured on Recurring Basis | Corporate Debt | Significant Unobservable Inputs (Level 3)
Assets measured at Fair Value
Available-for-sale fixed income	43,518	17,798
Fair Value Measured on Recurring Basis | Municipal
Assets measured at Fair Value
Available-for-sale fixed income	645,756	532,396
Fair Value Measured on Recurring Basis | Municipal | Significant Other Observable Inputs (Level 2)
Assets measured at Fair Value
Available-for-sale fixed income	$ 645,756	$ 532,396

Investments - Summary of Change

Investments - Summary of Changes in Balance of Level 3 securities (Details) - Regulation D Private Placement Fixed Income Securities $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)
Summary of changes in Level 3 securities
Beginning balance	$ 17,798
Net investment income	(53)
Net realized gains	(367)
Included in other comprehensive earnings	(170)
Total net realized and unrealized gains (losses)	(590)
Purchases	26,310
Ending balance	43,518
Net Realized Gains (Losses)
Summary of changes in Level 3 securities
Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in net realized gains	(367)
Other Comprehensive Earnings (Loss)
Summary of changes in Level 3 securities
Change in unrealized gains (losses) during the period for Level 3 assets held at period-end - included in net realized gains	$ (170)

Investments - Amortized Cost an

Investments - Amortized Cost and Fair Value of Available-for-sale Fixed Income Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost
Due in one year or less	$ 57,625
Due after one year through five years	626,953
Due after five years through 10 years	537,777
Due after 10 years	496,778
ABS/CMBS/MBS*	627,134
Total available-for-sale	2,346,267	$ 2,061,467
Fair Value
Due in one year or less	58,134
Due after one year through five years	647,068
Due after five years through 10 years	560,653
Due after 10 years	512,791
ABS/CMBS/MBS*	631,241
Total available-for-sale	$ 2,409,887	$ 2,196,626

Investments - Additional Inform

Investments - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021USD ($)security	Dec. 31, 2020USD ($)
Investment Holdings [Line Items]
Accrued investment income	$ 17,505,000	$ 16,126,000
ASU 2016-13
Investment Holdings [Line Items]
Change in Accounting Principle, Accounting Standards Update, Adopted [true false]	true
Change in Accounting Principle, Accounting Standards Update, Adoption Date	Jan. 1, 2020
Debt Securities
Investment Holdings [Line Items]
Accrued investment income	$ 16,400	14,900
Number of debt securities for which there is an allowance for credit losses | security	7
Net realized gains (losses)	$ 0	(600,000)
Number of debt securities in an unrealized loss position for which an allowance for credit losses has not been recorded | security	443
Unrealized loss	$ 16,891,000	2,554,000
Unrealized losses as percentage of fixed income portfolio cost basis	0.70%
Unrealized losses relative to total invested assets (as a percent)	0.50%
Number of unrealized loss positions | security	443
Number of securities in unrealized loss positions for 12 months or longer | security	76
ABS/CMBS/MBS
Investment Holdings [Line Items]
Percentage of securities of portfolio rated with highest credit rating by by one or more major rating agency	83.00%
Municipal
Investment Holdings [Line Items]
General obligations to state and local governments Percentage	48.00%
Revenue based obligations percentage	52.00%
Percentage of securities of portfolio rated as AA or better	90.00%
Percentage of securities of portfolio rated as A or better	99.00%
Unrealized loss	$ 4,281,000	$ 218,000

Investments - Amortized Cost _2

Investments - Amortized Cost and Fair Value of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Investment1 [Line Items]
Total available-for-sale	$ 2,346,267	$ 2,061,467
Allowance for Credit Losses	(441)	(397)
Gross Unrealized Gains	80,952	138,110
Gross Unrealized Losses	(16,891)	(2,554)
Fair Value	2,409,887	2,196,626
U.S. government
Investment1 [Line Items]
Total available-for-sale	127,752	170,110
Gross Unrealized Gains	6,846	13,504
Gross Unrealized Losses	(44)	(257)
Fair Value	134,554	183,357
U.S. Agency
Investment1 [Line Items]
Total available-for-sale	30,403	28,902
Gross Unrealized Gains	2,374	3,970
Gross Unrealized Losses	(17)
Fair Value	32,760	32,872
Non-U.S. govt. & agency
Investment1 [Line Items]
Total available-for-sale	8,297	10,298
Gross Unrealized Gains	338	667
Gross Unrealized Losses	(154)
Fair Value	8,481	10,965
Agency MBS
Investment1 [Line Items]
Total available-for-sale	362,861	384,015
Gross Unrealized Gains	9,277	18,789
Gross Unrealized Losses	(4,951)	(733)
Fair Value	367,187	402,071
ABS/CMBS/MBS
Investment1 [Line Items]
Total available-for-sale	264,273	213,223
Allowance for Credit Losses		(17)
Gross Unrealized Gains	2,120	5,580
Gross Unrealized Losses	(2,339)	(413)
Fair Value	264,054	218,373
Corporate Debt
Investment1 [Line Items]
Total available-for-sale	925,394	753,404
Allowance for Credit Losses	(441)	(380)
Gross Unrealized Gains	37,247	64,501
Gross Unrealized Losses	(5,105)	(933)
Fair Value	957,095	816,592
Municipal
Investment1 [Line Items]
Total available-for-sale	627,287	501,515
Gross Unrealized Gains	22,750	31,099
Gross Unrealized Losses	(4,281)	(218)
Fair Value	$ 645,756	$ 532,396

Investments - Schedule of Debt

Investments - Schedule of Debt Securities Available-for-sale Allowance for Credit Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Investment Holdings [Line Items]
Beginning balance	$ 397
Increase to allowance from securities for which credit losses were not previously recorded	4	$ 369
Reduction from securities sold during the period	(4)
Net increase (decrease) from securities that had an allowance at the beginning of the period	44
Ending balance	$ 441	397
ASU 2016-13
Investment Holdings [Line Items]
Adoption impact of ASU 2016-13		$ 28

Investments - Schedule of Secur

Investments - Schedule of Securities in an Unrealized Loss Position Segregated by Type and Length of Time in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
U.S. government
Fair value
Less than 12 months	$ 2,942	$ 5,680
Total Fair Value	2,942	5,680
Amortized Cost
Amortized cost, less than 12 months	2,986	5,937
Total Cost or Amortized Cost	2,986	5,937
Unrealized Loss
Less than 12 months	(44)	(257)
Total Unrealized Loss	(44)	(257)
U.S. Agency
Fair value
Less than 12 months	1,498
Total Fair Value	1,498
Amortized Cost
Amortized cost, less than 12 months	1,515
Total Cost or Amortized Cost	1,515
Unrealized Loss
Less than 12 months	(17)
Total Unrealized Loss	(17)
Non-U.S. govt. & agency
Fair value
Less than 12 months	4,346
Total Fair Value	4,346
Amortized Cost
Amortized cost, less than 12 months	4,500
Total Cost or Amortized Cost	4,500
Unrealized Loss
Less than 12 months	(154)
Total Unrealized Loss	(154)
Agency MBS
Fair value
Less than 12 months	102,145	43,999
12 months and greater	62,669
Total Fair Value	164,814	43,999
Amortized Cost
Amortized cost, less than 12 months	104,336	44,732
12 months and greater	65,429
Total Cost or Amortized Cost	169,765	44,732
Unrealized Loss
Less than 12 months	(2,191)	(733)
12 months and greater	(2,760)
Total Unrealized Loss	(4,951)	(733)
ABS/CMBS/MBS
Fair value
Less than 12 months	150,997	32,771
12 months and greater	3,935	16,161
Total Fair Value	154,932	48,932
Amortized Cost
Amortized cost, less than 12 months	153,235	33,094
12 months and greater	4,036	16,251
Total Cost or Amortized Cost	157,271	49,345
Unrealized Loss
Less than 12 months	(2,238)	(323)
12 months and greater	(101)	(90)
Total Unrealized Loss	(2,339)	(413)
Corporate Debt
Fair value
Less than 12 months	217,791	52,655
12 months and greater	53,818	6,235
Total Fair Value	271,609	58,890
Amortized Cost
Amortized cost, less than 12 months	221,010	53,440
12 months and greater	55,704	6,383
Total Cost or Amortized Cost	276,714	59,823
Unrealized Loss
Less than 12 months	(3,219)	(785)
12 months and greater	(1,886)	(148)
Total Unrealized Loss	(5,105)	(933)
Municipal
Fair value
Less than 12 months	162,998	25,676
12 months and greater	15,037
Total Fair Value	178,035	25,676
Amortized Cost
Amortized cost, less than 12 months	166,602	25,894
12 months and greater	15,714
Total Cost or Amortized Cost	182,316	25,894
Unrealized Loss
Less than 12 months	(3,604)	(218)
12 months and greater	(677)
Total Unrealized Loss	(4,281)	(218)
Debt Securities
Fair value
Less than 12 months	642,717	160,781
12 months and greater	135,459	22,396
Total Fair Value	778,176	183,177
Amortized Cost
Amortized cost, less than 12 months	654,184	163,097
12 months and greater	140,883	22,634
Total Cost or Amortized Cost	795,067	185,731
Unrealized Loss
Less than 12 months	(11,467)	(2,316)
12 months and greater	(5,424)	(238)
Total Unrealized Loss	$ (16,891)	$ (2,554)

Investments - Debt and Short-te

Investments - Debt and Short-term Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Nov. 10, 2021
Investment Holdings [Line Items]
Other investments	$ 50,501	$ 54,232
Investment in federal home loan bank stock	us-gaap:AssetPledgedAsCollateralMember	us-gaap:AssetPledgedAsCollateralMember
Fair value investments entities that calculate net asset value per share unfunded commitments	$ 20,100
Fixed maturities and short-term investments on deposit with either regulatory authorities or banks	86,200
FHLBC
Investment Holdings [Line Items]
Investments pledged as collateral	64,100
Federal home loan bank borrowings fair value disclosure				$ 50,000
Investment In Low Income Housing Tax Credit Partnership Net Of Amortization
Investment Holdings [Line Items]
Other investments	16,600	$ 20,300
Total tax benefit on investments in housing tax credit partnership	3,600	3,500	$ 2,500
Qualified affordable housing project investments, commitment		1,400
Investment in Private Funds
Investment Holdings [Line Items]
Other investments	28,600	$ 32,100
Fair value investments entities that calculate net asset value per share unfunded commitments	$ 8,800

Policy Acquisition Costs - Sche

Policy Acquisition Costs - Schedule of Policy Acquisition Costs Deferred and Amortized to Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Policy acquisition costs deferred and amortized to income
Deferred policy acquisition costs (DAC), beginning of year	$ 88,425	$ 85,044	$ 84,934
Deferred:
Direct commissions	236,145	200,917	185,164
Premium taxes	17,012	14,783	14,395
Ceding commissions	(47,592)	(42,115)	(31,140)
Net deferred	205,565	173,585	168,419
Amortized	190,437	170,204	168,309
DAC, end of year	103,553	88,425	85,044
Policy acquisition costs:
Amortized	190,437	170,204	168,309
Period costs:
Ceding commission - contingent	(4,303)	(4,053)	(3,034)
Other underwriting expenses	131,334	120,287	123,422
Total policy acquisition costs	$ 317,468	$ 286,438	$ 288,697

Debt - Additional Information (

Debt - Additional Information (Details) - USD ($)	Oct. 02, 2013	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Nov. 10, 2021
Debt Instrument [Line Items]
Outstanding debt balance		$ 199,700,000
Long-term debt		199,676,000	$ 149,489,000
Interest paid		$ 7,300,000	$ 7,300,000	$ 7,300,000
FHLBC | RLI Ins.
Debt Instrument [Line Items]
Debt instrument maturity date		Nov. 10, 2023
Amount borrowed from FHLB					$ 50,000,000
Interest paid monthly at an annualized rate					0.84%
Frequency of interest payment		monthly
Senior Notes Maturing September 15, 2023
Debt Instrument [Line Items]
Issue of senior notes by public debt offering	$ 150,000,000
Debt instrument maturity date	Sep. 15, 2023
Stated interest rate, payable semi-annually (as a percent)	4.875%
Proceeds from issuance of debt, net of discount and commission	$ 148,600,000
Estimated fair value of senior notes		$ 159,300,000
Long-term debt		$ 149,700,000
Senior Notes
Debt Instrument [Line Items]
Average interest rate on debt (as a percent)		4.77%	4.91%	4.91%
Line of Credit
Debt Instrument [Line Items]
Borrowing capacity under revolving line of credit facility		$ 60,000,000	$ 50,000,000
Maximum borrowing capacity conditional expansion		$ 120,000,000
Term of facility		3 years
Line of credit facility expiration date		Mar. 27, 2023
Amount outstanding on this facility		$ 0	$ 0	$ 0

Reinsurance - Additional Inform

Reinsurance - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Reinsurance Disclosures [Abstract]
Maximum amount beyond which net loss on any individual risk is limited through the purchase of reinsurance	$ 9,700,000
Percentage of reinsurance recoverables due from companies with financial strength ratings of "A" or better by A.M. Best and S&P rating services	89.00%
Amount of allowance for uncollectible amounts on paid recoverables	$ 16,100,000	$ 15,900,000
Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts	11,188,000	$ 8,634,000
Financing receivable, allowance for credit loss, write-off	0
Financing receivable, allowance for credit loss, recovery	200,000
Amount of allowance for uncollectible amounts due beyond one year	$ 0
Threshold period for including reinsurance receivables in the allowance for uncollectible amounts	1 year

Reinsurance - Schedule of Premi

Reinsurance - Schedule of Premiums Written and Earned Along with Losses and Settlement Expenses Incurred (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
WRITTEN
Direct	$ 1,313,093	$ 1,107,303	$ 1,039,955
Reinsurance assumed	34,261	29,129	25,047
Reinsurance ceded	(289,821)	(244,344)	(204,665)
Net	1,057,533	892,088	860,337
EARNED
Direct	1,222,346	1,062,608	981,121
Reinsurance assumed	30,950	27,651	40,173
Reinsurance ceded	(272,393)	(224,512)	(182,183)
Net	980,903	865,747	839,111
LOSSES AND SETTLEMENT EXPENSES INCURRED
Direct	703,903	608,638	521,055
Reinsurance assumed	18,087	18,783	21,951
Reinsurance ceded	(265,388)	(184,537)	(129,590)
Net	$ 456,602	$ 442,884	$ 413,416

Reinsurance - Schedule of Net R

Reinsurance - Schedule of Net Reinsurance Balances Recoverable, After Consideration of Collateral, from Top Reinsurers (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 706,248
Ceded Premiums Written	$ 289,821	$ 244,344	$ 204,665
Percent of Total Ceded Premium Written	100.00%
Reinsurance balances recoverable as a percentage of shareholder's equity, threshold for disclosure	2.00%
Reinsurer Concentration Risk | Reinsurance Recoverable
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	100.00%
Munich Re America / HSB | AM Best Rating, A+, Superior | S&P Rating, AA-, Very Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 102,632
Ceded Premiums Written	$ 34,462
Percent of Total Ceded Premium Written	11.90%
Munich Re America / HSB | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, AA-, Very Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	14.50%
Renaissance Re | AM Best Rating, A+, Superior | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 58,417
Ceded Premiums Written	$ 25,001
Percent of Total Ceded Premium Written	8.60%
Renaissance Re | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	8.30%
Endurance Re | AM Best Rating, A+, Superior | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 47,136
Ceded Premiums Written	$ 9,865
Percent of Total Ceded Premium Written	3.40%
Endurance Re | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	6.70%
Scor Re | AM Best Rating, A+, Superior | S&P Rating, AA-, Very Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 37,160
Ceded Premiums Written	$ 13,398
Percent of Total Ceded Premium Written	4.60%
Scor Re | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, AA-, Very Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	5.30%
Aspen UK Ltd. | AM Best Rating, A, Excellent | S&P Rating, A-, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 36,164
Ceded Premiums Written	$ 9,402
Percent of Total Ceded Premium Written	3.20%
Aspen UK Ltd. | Reinsurer Concentration Risk | AM Best Rating, A, Excellent | Reinsurance Recoverable | S&P Rating, A-, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	5.10%
Berkley Insurance Co. | AM Best Rating, A+, Superior | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 36,033
Ceded Premiums Written	$ 12,950
Percent of Total Ceded Premium Written	4.50%
Berkley Insurance Co. | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	5.10%
Hannover Ruckversicherung | AM Best Rating, A+, Superior | S&P Rating, AA-, Very Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 33,125
Ceded Premiums Written	$ 12,942
Percent of Total Ceded Premium Written	4.50%
Hannover Ruckversicherung | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, AA-, Very Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	4.70%
Safety National | AM Best Rating, A++, Superior | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 32,196
Ceded Premiums Written	$ 15,544
Percent of Total Ceded Premium Written	5.40%
Safety National | Reinsurer Concentration Risk | AM Best Rating, A++, Superior | Reinsurance Recoverable | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	4.60%
Nationwide Mutual | AM Best Rating, A+, Superior | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 29,818
Ceded Premiums Written	$ 17,738
Percent of Total Ceded Premium Written	6.10%
Nationwide Mutual | Reinsurer Concentration Risk | AM Best Rating, A+, Superior | Reinsurance Recoverable | S&P Rating, A+, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	4.20%
Liberty Mutual | AM Best Rating, A, Excellent | S&P Rating, A, Strong
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 23,236
Ceded Premiums Written	$ 7,240
Percent of Total Ceded Premium Written	2.50%
Liberty Mutual | Reinsurer Concentration Risk | AM Best Rating, A, Excellent | Reinsurance Recoverable | S&P Rating, A, Strong
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	3.30%
All Other Reinsurers
Ceded Credit Risk [Line Items]
Net Reinsurer Exposure	$ 270,331
Ceded Premiums Written	$ 131,279
Percent of Total Ceded Premium Written	45.30%
All Other Reinsurers | Reinsurer Concentration Risk | Reinsurance Recoverable
Ceded Credit Risk [Line Items]
Percent of Total Net Reinsurer Exposure	38.20%

Historical Loss and LAE Devel_3

Historical Loss and LAE Development - Schedule of Reconciliation of Unpaid Losses and Settlement Expenses (LAE) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Unpaid losses and LAE at beginning of year:
Gross	$ 1,750,049	$ 1,574,352	$ 1,461,348
Ceded	(443,729)	(384,517)	(364,999)
Net	1,306,320	1,189,835	1,096,349
Increase (decrease) in incurred losses and LAE:
Current accident year	582,065	543,937	488,700
Prior accident years	(125,463)	(101,053)	(75,284)
Total incurred	456,602	442,884	413,416
Loss and LAE payments for claims incurred:
Current accident year	(101,590)	(93,077)	(80,055)
Prior accident year	(225,863)	(231,977)	(239,875)
Total paid	(327,453)	(325,054)	(319,930)
Net unpaid losses and LAE at end of year	1,435,469	1,306,320	1,189,835
Unpaid losses and LAE at end of year:
Gross	2,043,555	1,750,049	1,574,352
Ceded	(608,086)	(443,729)	(384,517)
Net unpaid losses and LAE at end of year	$ 1,435,469	1,306,320	1,189,835
ASU 2016-13 | Cumulative Effect, Period of Adoption, Adjustment
Unpaid losses and LAE at beginning of year:
Ceded		$ (1,345)
Unpaid losses and LAE at end of year:
Ceded			$ (1,345)

Historical Loss and LAE Devel_4

Historical Loss and LAE Development - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	$ 608,086	$ 443,729	$ 384,517	$ 364,999
(Favorable)/unfavorable reserve development	(125,463)	(101,053)	(75,284)
Casualty Segment
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(108,632)	(75,075)	(62,497)
Property segment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	65,098	40,257
(Favorable)/unfavorable reserve development	(10,981)	(13,019)	(4,461)
Property segment | Marine
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(6,600)	(6,500)	(2,400)
Property segment | Commercial Property
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(2,000)	(5,200)
Property segment | Specialty Personal
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development			(1,100)
Surety Segment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	50,743	4,017
(Favorable)/unfavorable reserve development	(5,850)	(12,959)	(8,326)
Surety Segment | Contract Surety Product
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(4,600)	(5,900)	(4,200)
Surety Segment | Commercial Surety Product
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development		(3,800)	(5,800)
Surety Segment | Miscellaneous Surety Product
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development			1,700
Primary Occurrence | Casualty Segment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	43,688	35,202
Primary Occurrence | Casualty Segment | General Liability
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(25,300)	(17,900)	(11,800)
Primary Occurrence | Casualty Segment | P&C Package
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(7,500)		(6,300)
Excess Occurrence | Casualty Segment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	122,092	88,528
Excess Occurrence | Casualty Segment | Commercial Products
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(10,500)	(12,500)	(6,800)
Excess Occurrence | Casualty Segment | Personal Umbrella
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(10,400)		(7,800)
Claims Made | Casualty Segment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	271,259	223,020
Claims Made | Casualty Segment | Miscellaneous Professional Liability
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(14,200)	(7,800)	(10,200)
Claims Made | Casualty Segment | Executive Products
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(5,900)		7,300
Claims Made | Casualty Segment | Medical Professional Liability
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development		(6,100)	2,300
Transportation | Casualty Segment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded	66,283	53,251
(Favorable)/unfavorable reserve development	$ (20,100)	$ (19,100)	(16,600)
ASU 2016-13 | Cumulative Effect, Period of Adoption, Adjustment
(Favorable)/Unfavorable Reserve Development
Unpaid losses and LAE, Ceded			$ 1,345

Historical Loss and LAE Devel_5

Historical Loss and LAE Development - Incurred Losses and Loss Adjustment Expenses, Net of Reinsurance (Details) $ in Thousands	Dec. 31, 2021USD ($)Claim	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Dec. 31, 2012USD ($)
Claims Development
Liabilities for losses and loss adjustment expenses, net of reinsurance	$ 1,435,469	$ 1,306,320
Casualty Segment | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	942,920
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	500,538
All outstanding liabilities before 2012, net of reinsurance	10,760
Liabilities for losses and loss adjustment expenses, net of reinsurance	453,142	432,823
Casualty Segment | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	566,925
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	200,841
All outstanding liabilities before 2012, net of reinsurance	18,495
Liabilities for losses and loss adjustment expenses, net of reinsurance	384,579	312,827
Casualty Segment | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	485,084
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	278,954
All outstanding liabilities before 2012, net of reinsurance	3,575
Liabilities for losses and loss adjustment expenses, net of reinsurance	209,705	214,103
Casualty Segment | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	417,878
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	286,875
All outstanding liabilities before 2012, net of reinsurance	528
Liabilities for losses and loss adjustment expenses, net of reinsurance	131,531	129,852
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2012 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	60,155	60,591	$ 60,465	$ 60,328	$ 59,488	$ 59,028	$ 61,072	$ 65,893	$ 78,406	$ 91,807
Total IBNR	$ 1,589
Cumulative number of reported claims | Claim	5,192
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 56,660	55,679	54,391	51,611	47,970	43,276	33,822	23,889	14,539	5,897
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2012 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	26,848	26,129	25,286	23,020	22,433	21,231	21,885	21,021	21,558	29,042
Total IBNR	$ 783
Cumulative number of reported claims | Claim	867
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 22,246	22,202	21,993	19,310	17,747	16,879	15,380	8,843	3,573	1,315
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2012 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	22,236	22,325	20,785	17,569	17,612	18,022	19,590	20,727	26,144	27,576
Total IBNR	$ 207
Cumulative number of reported claims | Claim	804
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 17,148	16,892	16,450	15,621	14,378	10,968	9,218	6,898	4,086	433
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2012 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	23,955	23,845	23,731	23,305	23,620	23,689	23,511	22,924	22,203	21,452
Total IBNR	$ 74
Cumulative number of reported claims | Claim	2,287
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 23,181	23,181	23,180	22,730	22,566	20,931	17,318	12,394	8,533	4,466
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2013 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	57,519	57,106	59,116	59,556	60,162	60,329	62,882	67,297	80,823
Total IBNR	$ 2,096
Cumulative number of reported claims | Claim	4,324
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 50,597	49,411	47,783	45,753	40,609	34,786	22,366	13,021	6,334
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2013 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	24,836	25,073	25,496	24,922	25,599	25,425	26,857	34,824	39,984
Total IBNR	$ 1,396
Cumulative number of reported claims | Claim	949
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 22,154	21,229	18,524	17,956	16,967	14,545	10,967	5,701	1,060
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2013 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	37,950	37,974	38,352	37,959	38,473	40,288	44,054	41,488	40,095
Total IBNR	$ 767
Cumulative number of reported claims | Claim	1,042
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 36,078	35,476	34,535	32,789	29,678	26,121	18,425	7,073	792
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2013 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	39,586	39,183	39,309	39,974	38,811	37,673	32,989	32,853	32,742
Total IBNR	$ 118
Cumulative number of reported claims | Claim	2,853
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 38,172	37,915	37,327	35,923	33,480	28,220	19,761	11,978	5,306
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2014 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	63,727	65,636	66,702	66,389	67,237	71,592	79,497	88,092
Total IBNR	$ 3,034
Cumulative number of reported claims | Claim	4,295
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 56,784	55,965	52,387	47,343	40,270	29,545	18,771	11,436
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2014 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	35,683	35,128	33,458	33,372	32,274	35,119	39,095	50,889
Total IBNR	$ 2,622
Cumulative number of reported claims | Claim	923
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 28,963	26,068	23,376	22,541	18,852	11,002	4,006	1,899
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2014 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	52,619	53,783	53,841	51,554	55,350	58,152	55,386	53,929
Total IBNR	$ 1,504
Cumulative number of reported claims | Claim	1,305
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 50,714	46,122	44,127	40,080	35,755	27,923	9,775	1,705
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2014 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	41,974	41,156	40,508	40,202	38,590	36,452	33,015	38,361
Total IBNR	$ 297
Cumulative number of reported claims | Claim	3,099
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 40,427	40,006	38,282	33,190	27,457	19,676	13,933	7,125
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2015 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	75,438	75,470	76,398	78,675	83,579	84,975	94,835
Total IBNR	$ 6,644
Cumulative number of reported claims | Claim	4,406
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 62,997	58,866	54,270	45,056	33,020	19,902	10,157
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2015 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	41,690	42,446	43,328	42,840	47,392	50,857	53,672
Total IBNR	$ 5,439
Cumulative number of reported claims | Claim	699
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 32,752	31,352	28,756	23,184	19,571	10,127	2,048
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2015 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	38,609	39,619	39,653	39,906	42,206	47,831	55,006
Total IBNR	$ 2,759
Cumulative number of reported claims | Claim	1,338
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 33,529	32,241	28,795	20,920	16,774	10,738	2,215
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2015 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	45,807	45,525	45,162	46,395	47,021	46,258	38,561
Total IBNR	$ 708
Cumulative number of reported claims | Claim	3,186
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 42,626	41,345	39,339	37,222	29,554	20,709	6,984
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2016 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	79,440	83,374	85,449	90,611	96,753	101,950
Total IBNR	$ 10,352
Cumulative number of reported claims | Claim	4,315
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 60,349	56,152	48,042	35,764	24,186	10,142
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2016 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	29,671	30,251	33,125	37,676	49,385	56,341
Total IBNR	$ 11,023
Cumulative number of reported claims | Claim	646
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 14,400	12,703	10,054	7,441	3,396	1,068
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2016 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	65,078	64,730	67,728	69,493	67,760	59,992
Total IBNR	$ 4,808
Cumulative number of reported claims | Claim	1,507
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 52,846	47,999	39,370	27,465	14,558	2,060
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2016 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	53,915	52,818	52,277	54,105	53,519	50,430
Total IBNR	$ 1,235
Cumulative number of reported claims | Claim	3,943
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 47,488	43,564	38,001	30,354	18,354	8,923
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2017 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	90,759	95,513	102,583	111,391	119,741
Total IBNR	$ 15,999
Cumulative number of reported claims | Claim	4,491
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 62,236	52,823	38,783	25,933	13,154
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2017 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	43,249	44,737	48,363	55,868	62,863
Total IBNR	$ 16,698
Cumulative number of reported claims | Claim	631
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 18,470	15,441	9,275	5,679	17
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2017 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	59,907	57,450	62,714	62,450	60,572
Total IBNR	$ 9,039
Cumulative number of reported claims | Claim	1,648
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 42,918	36,522	22,728	11,350	2,455
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2017 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	45,351	43,764	45,017	53,641	55,640
Total IBNR	$ 2,257
Cumulative number of reported claims | Claim	3,639
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 36,141	30,260	24,090	17,070	7,979
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2018 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	115,076	125,731	130,281	141,513
Total IBNR	$ 32,268
Cumulative number of reported claims | Claim	4,822
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 63,980	48,424	32,365	15,066
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2018 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	51,023	54,626	62,646	69,362
Total IBNR	$ 26,824
Cumulative number of reported claims | Claim	590
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 17,294	10,801	5,823	2,506
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2018 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	48,457	56,468	62,416	66,128
Total IBNR	$ 17,399
Cumulative number of reported claims | Claim	1,391
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 24,918	18,840	11,965	1,964
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2018 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	36,468	38,719	54,592	57,597
Total IBNR	$ 4,946
Cumulative number of reported claims | Claim	3,402
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 24,503	19,216	12,827	6,980
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2019 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	120,570	135,209	146,011
Total IBNR	$ 62,738
Cumulative number of reported claims | Claim	5,175
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 41,911	30,673	15,698
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2019 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	79,083	89,691	88,078
Total IBNR	$ 47,276
Cumulative number of reported claims | Claim	603
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 25,389	19,044	4,213
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2019 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	52,224	61,712	62,918
Total IBNR	$ 26,387
Cumulative number of reported claims | Claim	1,508
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 14,117	8,123	1,839
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2019 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	43,976	56,129	58,297
Total IBNR	$ 9,024
Cumulative number of reported claims | Claim	3,313
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 21,120	15,852	7,148
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2020 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	137,439	145,171
Total IBNR	$ 88,880
Cumulative number of reported claims | Claim	4,394
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 30,596	17,096
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2020 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	98,409	107,579
Total IBNR	$ 74,182
Cumulative number of reported claims | Claim	471
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 13,856	2,901
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2020 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	56,785	60,278
Total IBNR	$ 43,408
Cumulative number of reported claims | Claim	1,287
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 5,687	1,488
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2020 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	35,524	43,573
Total IBNR	$ 16,243
Cumulative number of reported claims | Claim	1,637
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 7,876	3,986
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2021 | Primary Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	142,797
Total IBNR	$ 112,702
Cumulative number of reported claims | Claim	3,678
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 14,428
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2021 | Excess Occurrence
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	136,433
Total IBNR	$ 93,982
Cumulative number of reported claims | Claim	371
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 5,317
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2021 | Claims Made
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	51,219
Total IBNR	$ 42,451
Cumulative number of reported claims | Claim	1,112
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 999
Casualty Segment | Short-duration Insurance Contracts, Accident Year 2021 | Transportation
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	51,322
Total IBNR	$ 9,745
Cumulative number of reported claims | Claim	2,161
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 5,341
Property segment
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	766,882
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	642,870
All outstanding liabilities before 2012, net of reinsurance	640
Liabilities for losses and loss adjustment expenses, net of reinsurance	124,652	103,383
Property segment | Short-duration Insurance Contracts, Accident Year 2012
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	77,883	77,924	78,002	78,161	78,125	79,175	77,569	79,181	80,155	85,485
Total IBNR	$ 7
Cumulative number of reported claims | Claim	2,640
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 77,360	77,347	77,323	77,159	76,152	75,640	73,705	72,057	66,509	39,074
Property segment | Short-duration Insurance Contracts, Accident Year 2013
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	61,400	61,623	61,776	61,834	61,914	62,114	62,173	62,090	63,864
Total IBNR	$ 36
Cumulative number of reported claims | Claim	2,996
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 61,188	61,335	61,325	61,195	60,520	59,259	57,407	50,840	32,208
Property segment | Short-duration Insurance Contracts, Accident Year 2014
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	49,520	49,479	49,444	49,217	48,761	48,801	49,441	56,587
Total IBNR	$ 52
Cumulative number of reported claims | Claim	4,562
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 49,317	49,259	49,027	47,799	46,528	46,148	43,380	30,550
Property segment | Short-duration Insurance Contracts, Accident Year 2015
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	52,878	52,781	53,111	52,720	53,958	56,103	59,863
Total IBNR	$ 96
Cumulative number of reported claims | Claim	4,075
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 52,400	52,342	52,078	51,290	50,197	49,348	32,184
Property segment | Short-duration Insurance Contracts, Accident Year 2016
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	55,383	55,424	55,930	55,384	55,594	62,900
Total IBNR	$ 177
Cumulative number of reported claims | Claim	3,377
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 54,747	54,328	53,006	51,371	46,921	33,134
Property segment | Short-duration Insurance Contracts, Accident Year 2017
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	82,319	82,671	84,961	83,273	90,803
Total IBNR	$ 1,321
Cumulative number of reported claims | Claim	2,893
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 80,581	78,360	74,415	66,818	41,314
Property segment | Short-duration Insurance Contracts, Accident Year 2018
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	80,470	79,961	83,457	89,091
Total IBNR	$ 3,642
Cumulative number of reported claims | Claim	2,337
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 75,253	72,357	68,264	37,048
Property segment | Short-duration Insurance Contracts, Accident Year 2019
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	61,116	65,189	71,232
Total IBNR	$ 3,193
Cumulative number of reported claims | Claim	2,446
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 55,092	51,740	30,703
Property segment | Short-duration Insurance Contracts, Accident Year 2020
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	110,466	118,247
Total IBNR	$ 17,071
Cumulative number of reported claims | Claim	2,837
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 79,660	43,192
Property segment | Short-duration Insurance Contracts, Accident Year 2021
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	135,447
Total IBNR	$ 45,890
Cumulative number of reported claims | Claim	2,616
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 57,272
Surety Segment
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	84,041
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	49,729
All outstanding liabilities before 2012, net of reinsurance	(68)
Liabilities for losses and loss adjustment expenses, net of reinsurance	34,244	27,009
Surety Segment | Short-duration Insurance Contracts, Accident Year 2012
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	7,131	6,985	7,082	7,099	7,471	7,867	8,180	8,667	11,452	17,114
Total IBNR	$ 2
Cumulative number of reported claims | Claim	1,480
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 7,083	6,941	6,996	7,065	7,406	7,536	7,416	6,726	6,680	$ 1,883
Surety Segment | Short-duration Insurance Contracts, Accident Year 2013
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	5,046	5,107	5,209	5,231	5,271	5,399	6,170	7,516	16,080
Total IBNR	$ 10
Cumulative number of reported claims | Claim	1,409
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 5,029	5,061	5,128	5,150	5,098	4,911	4,701	2,856	$ 1,116
Surety Segment | Short-duration Insurance Contracts, Accident Year 2014
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	4,227	4,266	4,319	4,267	4,427	5,225	8,106	16,450
Total IBNR	$ 8
Cumulative number of reported claims | Claim	1,355
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 4,197	4,214	4,234	4,131	4,059	4,166	4,283	$ 722
Surety Segment | Short-duration Insurance Contracts, Accident Year 2015
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	9,275	9,521	9,792	10,456	11,113	12,957	16,958
Total IBNR	$ 59
Cumulative number of reported claims | Claim	1,242
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 9,168	9,186	9,183	9,436	7,695	6,719	$ 3,192
Surety Segment | Short-duration Insurance Contracts, Accident Year 2016
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	7,948	8,391	8,895	9,351	11,062	18,928
Total IBNR	$ 125
Cumulative number of reported claims | Claim	1,381
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 7,673	8,086	7,640	6,299	5,817	$ 3,087
Surety Segment | Short-duration Insurance Contracts, Accident Year 2017
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	8,034	8,116	8,798	8,641	16,127
Total IBNR	$ 306
Cumulative number of reported claims | Claim	1,790
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 7,362	7,221	7,062	2,862	$ 979
Surety Segment | Short-duration Insurance Contracts, Accident Year 2018
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	3,947	4,564	7,227	16,765
Total IBNR	$ 713
Cumulative number of reported claims | Claim	1,323
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 2,536	2,368	2,588	$ 1,835
Surety Segment | Short-duration Insurance Contracts, Accident Year 2019
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	5,053	7,205	14,785
Total IBNR	$ 2,047
Cumulative number of reported claims | Claim	1,112
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 2,765	2,433	$ 336
Surety Segment | Short-duration Insurance Contracts, Accident Year 2020
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	14,840	19,241
Total IBNR	$ 7,212
Cumulative number of reported claims | Claim	748
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 2,719	$ 835
Surety Segment | Short-duration Insurance Contracts, Accident Year 2021
Claims Development
Incurred losses and loss adjustment expenses, net of reinsurance	18,540
Total IBNR	$ 15,647
Cumulative number of reported claims | Claim	444
Cumulative paid claims and allocated claim adjustment expenses, net of reinsurance	$ 1,197

Historical Loss and LAE Devel_6

Historical Loss and LAE Development - Cumulative Paid Loss and Loss Adjustment Expenses, Net of Reinsurance (Details)	Dec. 31, 2021
Property segment
Shortduration Insurance Contracts Historical Claims Duration [Line Items]
Average annual percentage payout of incurred losses by age, Year 1	51.30%
Average annual percentage payout of incurred losses by age, Year 2	31.80%
Average annual percentage payout of incurred losses by age, Year 3	6.60%
Average annual percentage payout of incurred losses by age, Year 4	2.80%
Average annual percentage payout of incurred losses by age, Year 5	2.30%
Average annual percentage payout of incurred losses by age, Year 6	1.10%
Average annual percentage payout of incurred losses by age, Year 7	0.50%
Average annual percentage payout of incurred losses by age, Year 8	0.10%
Average annual percentage payout of incurred losses by age, Year 9	(0.10%)
Average annual percentage payout of incurred losses by age, Year 10	0.00%
Surety Segment
Shortduration Insurance Contracts Historical Claims Duration [Line Items]
Average annual percentage payout of incurred losses by age, Year 1	21.60%
Average annual percentage payout of incurred losses by age, Year 2	39.50%
Average annual percentage payout of incurred losses by age, Year 3	13.00%
Average annual percentage payout of incurred losses by age, Year 4	7.60%
Average annual percentage payout of incurred losses by age, Year 5	2.00%
Average annual percentage payout of incurred losses by age, Year 6	(0.70%)
Average annual percentage payout of incurred losses by age, Year 7	(1.50%)
Average annual percentage payout of incurred losses by age, Year 8	(0.90%)
Average annual percentage payout of incurred losses by age, Year 9	(0.70%)
Average annual percentage payout of incurred losses by age, Year 10	2.00%
Primary Occurrence | Casualty Segment
Shortduration Insurance Contracts Historical Claims Duration [Line Items]
Average annual percentage payout of incurred losses by age, Year 1	12.80%
Average annual percentage payout of incurred losses by age, Year 2	13.30%
Average annual percentage payout of incurred losses by age, Year 3	14.80%
Average annual percentage payout of incurred losses by age, Year 4	16.50%
Average annual percentage payout of incurred losses by age, Year 5	11.60%
Average annual percentage payout of incurred losses by age, Year 6	7.20%
Average annual percentage payout of incurred losses by age, Year 7	5.20%
Average annual percentage payout of incurred losses by age, Year 8	2.90%
Average annual percentage payout of incurred losses by age, Year 9	2.10%
Average annual percentage payout of incurred losses by age, Year 10	1.60%
Excess Occurrence | Casualty Segment
Shortduration Insurance Contracts Historical Claims Duration [Line Items]
Average annual percentage payout of incurred losses by age, Year 1	4.00%
Average annual percentage payout of incurred losses by age, Year 2	12.20%
Average annual percentage payout of incurred losses by age, Year 3	15.40%
Average annual percentage payout of incurred losses by age, Year 4	15.00%
Average annual percentage payout of incurred losses by age, Year 5	9.20%
Average annual percentage payout of incurred losses by age, Year 6	4.30%
Average annual percentage payout of incurred losses by age, Year 7	4.80%
Average annual percentage payout of incurred losses by age, Year 8	9.70%
Average annual percentage payout of incurred losses by age, Year 9	2.30%
Average annual percentage payout of incurred losses by age, Year 10	0.20%
Claims Made | Casualty Segment
Shortduration Insurance Contracts Historical Claims Duration [Line Items]
Average annual percentage payout of incurred losses by age, Year 1	3.20%
Average annual percentage payout of incurred losses by age, Year 2	16.10%
Average annual percentage payout of incurred losses by age, Year 3	19.60%
Average annual percentage payout of incurred losses by age, Year 4	15.70%
Average annual percentage payout of incurred losses by age, Year 5	11.60%
Average annual percentage payout of incurred losses by age, Year 6	9.50%
Average annual percentage payout of incurred losses by age, Year 7	4.30%
Average annual percentage payout of incurred losses by age, Year 8	5.00%
Average annual percentage payout of incurred losses by age, Year 9	1.80%
Average annual percentage payout of incurred losses by age, Year 10	1.20%
Transportation | Casualty Segment
Shortduration Insurance Contracts Historical Claims Duration [Line Items]
Average annual percentage payout of incurred losses by age, Year 1	15.50%
Average annual percentage payout of incurred losses by age, Year 2	18.30%
Average annual percentage payout of incurred losses by age, Year 3	17.00%
Average annual percentage payout of incurred losses by age, Year 4	17.10%
Average annual percentage payout of incurred losses by age, Year 5	11.70%
Average annual percentage payout of incurred losses by age, Year 6	7.40%
Average annual percentage payout of incurred losses by age, Year 7	2.80%
Average annual percentage payout of incurred losses by age, Year 8	1.50%
Average annual percentage payout of incurred losses by age, Year 9	0.30%
Average annual percentage payout of incurred losses by age, Year 10	0.00%

Historical Loss and LAE Devel_7

Historical Loss and LAE Development - Reconciliation of Incurred and Paid Loss Development to the Liability for Unpaid Losses and Settlement Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Unpaid losses and settlement expenses	$ 2,043,555	$ 1,750,049	$ 1,574,352	$ 1,461,348
Liabilities for losses and loss adjustment expenses, net of reinsurance	1,435,469	1,306,320
Unallocated loss adjustment expenses	59,391	54,954
Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts	11,188	8,634
Other	27,037	22,735
Reinsurance recoverable on unpaid claims	608,086	443,729	$ 384,517	$ 364,999
Other	111	8,088
Total gross liability for unpaid loss and settlement expenses	2,043,555	1,750,049
Casualty Segment | Primary Occurrence
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Liabilities for losses and loss adjustment expenses, net of reinsurance	453,142	432,823
Reinsurance recoverable on unpaid claims	43,688	35,202
Casualty Segment | Excess Occurrence
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Liabilities for losses and loss adjustment expenses, net of reinsurance	384,579	312,827
Reinsurance recoverable on unpaid claims	122,092	88,528
Casualty Segment | Claims Made
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Liabilities for losses and loss adjustment expenses, net of reinsurance	209,705	214,103
Reinsurance recoverable on unpaid claims	271,259	223,020
Casualty Segment | Transportation
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Liabilities for losses and loss adjustment expenses, net of reinsurance	131,531	129,852
Reinsurance recoverable on unpaid claims	66,283	53,251
Property segment
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Liabilities for losses and loss adjustment expenses, net of reinsurance	124,652	103,383
Reinsurance recoverable on unpaid claims	65,098	40,257
Surety Segment
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability
Liabilities for losses and loss adjustment expenses, net of reinsurance	34,244	27,009
Reinsurance recoverable on unpaid claims	$ 50,743	$ 4,017

Historical Loss and LAE Devel_8

Historical Loss and LAE Development - Reserve Development (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	$ (125,463)	$ (101,053)	$ (75,284)
Casualty Segment
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(108,632)	(75,075)	(62,497)
Property segment
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	(10,981)	(13,019)	(4,461)
Surety Segment
(Favorable)/Unfavorable Reserve Development
(Favorable)/unfavorable reserve development	$ (5,850)	$ (12,959)	$ (8,326)

Historical Loss and LAE Devel_9

Historical Loss and LAE Development - Environmental, Asbestos and Mass Tort Exposures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Unpaid losses and LAE at beginning of year:
Gross	$ 2,043,555	$ 1,750,049	$ 1,574,352	$ 1,461,348
Net	1,435,469	1,306,320	1,189,835	$ 1,096,349
Asbestos and Environmental Exposures
Loss and LAE Payments (Cumulative):
Gross	141,768	139,804	137,485
Ceded	(69,576)	(69,219)	(68,849)
Net	72,192	70,585	68,636
Unpaid losses and LAE at beginning of year:
Gross	25,747	22,485	22,616
Ceded	(5,718)	(4,619)	(5,149)
Net	$ 20,029	$ 17,866	$ 17,467

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Tax discounting of unpaid losses and settlement expenses	$ 22,637	$ 21,096
Unearned premium offset	23,080	19,862
Deferred compensation	3,469	2,829
Stock option expense	3,089	2,749
Lease liability	3,796	3,971
Other	367	389
Deferred tax assets before allowance	56,438	50,896
Total deferred tax assets	56,438	50,896
Deferred tax liabilities:
Net unrealized appreciation of securities	76,533	77,639
Deferred policy acquisition costs	21,746	18,569
Lease asset	3,101	3,402
Discounting of unpaid losses and settlement expenses - Tax Cuts and Jobs Act (TCJA) implementation offset	2,545	3,181
Fixed assets	3,518	3,439
Intangible assets	1,537	1,558
Undistributed earnings of unconsolidated investees	29,515	21,813
Other	1,452	1,530
Total deferred tax liabilities	139,947	131,131
Net deferred tax liability	$ (83,509)	$ (80,235)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax [Line Items]
U.S. federal tax rate	21.00%	21.00%	21.00%
Capital gains rate (as a percent)	21.00%
Dividends received		$ 4,675	$ 13,200
Unconsolidated investee dividends		$ 479	$ 1,802
Effective rate reduction due to unconsolidated investee dividends (as a percent)		0.20%	0.80%
ESOP dividends paid deduction	$ 1,566	$ 1,083	$ 1,122
Effective rate reduction due to dividends paid to ESOP (as a percent)	0.50%	0.60%	0.50%
Expected effective tax rate when deferred items reverse in future years (as a percent)	21.00%
Federal and state income taxes paid	$ 38,600	$ 23,700	$ 25,600
Maui Jim Inc.
Income Tax [Line Items]
Dividends received			13,200
Unconsolidated investee dividends			$ 1,800
Lower tax rate (as a percent)			7.40%
Prime Holdings Insurance Services, Inc. (Prime)
Income Tax [Line Items]
Dividends received		4,700
Unconsolidated investee dividends		$ 500
Lower tax rate (as a percent)		10.80%

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Income Tax Expense (Benefit) Attributable to Income from Operations with Amounts Computed by Applying U.S. Federal Tax Rate to Pretax Income from Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of income tax expense reported to amount computed by applying the U.S. federal tax rate
Provision for income taxes at the statutory federal tax rates	$ 72,307	$ 39,867	$ 48,874
Increase (reduction) in taxes resulting from:
Excess tax benefit on share-based compensation	(3,090)	(3,537)	(3,958)
Tax-exempt interest income	(1,219)	(1,293)	(1,238)
Dividends received deduction	(891)	(883)	(823)
Investment tax credit	(3,491)	(2,435)
ESOP dividends paid deduction	(1,566)	(1,083)	(1,122)
Unconsolidated investee dividends		(479)	(1,802)
Nondeductible expenses	3,834	1,878	1,649
Other items, net	(917)	715	(488)
Income tax expense	$ 64,967	$ 32,750	$ 41,092
Reconciliation of income tax expense rate to the U.S. federal tax rate
Tax rate used (as a percent)	21.00%	21.00%	21.00%
Excess tax benefit on share-based compensation (as a percent)	(0.90%)	(1.80%)	(1.70%)
Effective rate reduction due to tax exempt interest income (as a percent)	(0.30%)	(0.70%)	(0.50%)
Effective rate reduction due to dividend received (as a percent)	(0.30%)	(0.50%)	(0.40%)
Effective rate reduction due to investment tax credit (as a percent)	(1.00%)	(1.30%)
Effective rate reduction due to dividend paid to ESOP (as a percent)	(0.50%)	(0.60%)	(0.50%)
Effective rate reduction due to unconsolidated investee dividends (as a percent)		(0.20%)	(0.80%)
Effective rate reduction due to nondeductible expenses (as a percent)	1.10%	1.00%	0.70%
Effective rate reduction due to other items, net (as a percent)	(0.20%)	0.40%	(0.10%)
Total tax expense	18.90%	17.30%	17.70%

Employee Benefits - Employee St

Employee Benefits - Employee Stock Ownership, 401(K) and Deferred Compensation Plan - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Employee Stock Ownership, 401(K) And Deferred Compensation Plan
Annual expenses for incentive plans	$ 39.1	$ 26.6	$ 30.1
Employee 401(k) Plans
Employee Stock Ownership, 401(K) And Deferred Compensation Plan
Employer contribution as a percent of eligible compensation	3.00%
Vesting percentage in basic and voluntary contributions	100.00%
ESOP and 401(k) Plans
Employee Stock Ownership, 401(K) And Deferred Compensation Plan
Vesting period of profit sharing contributions	3 years
Expenses recognized	$ 18	$ 14.4	$ 15.7
Employee Stock Ownership Plan (ESOP)
Employee Stock Ownership, 401(K) And Deferred Compensation Plan
Shares purchased under defined contribution plan	65,815	94,194	60,768
Average price of shares purchased (in dollars per share)	$ 107.95	$ 82.67	$ 69.99
Aggregate price of shares purchased	$ 7.1	$ 7.8	$ 4.3
Shares held by the ESOP	2,495,777
Deferred Compensation Plan
Employee Stock Ownership, 401(K) And Deferred Compensation Plan
Assets held under trust	$ 51.4

Employee Benefits - Stock Plans

Employee Benefits - Stock Plans - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended			60 Months Ended	80 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	May 06, 2015	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options granted (in shares)	260,271
Intrinsic value of options	$ 12.2	$ 15.5	$ 20
RLI Corp. Long-Term Incentive Plan (2010 LTIP)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares authorized for grant				4,000,000
Options granted (in shares)				2,878,000
RLI Corp. Long-Term Incentive Plan (2015 LTIP)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares authorized for grant	4,000,000				4,000,000
Options granted (in shares)	277,051				2,900,420
Stock-based compensation expenses	$ 6.4	5.4	6
Income tax benefit from stock-based compensation	1	$ 0.9	$ 0.9
Unrecognized stock-based compensation expense	$ 6				$ 6
Stock-based compensation expenses, recognition period	2 years 3 months 29 days
RLI Corp. Long-Term Incentive Plan (LTIP 2010 and LTIP 2015) | Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	5 years
Term of options	8 years
Age and period of service of the participant to be eligible for retirement	75 years

Employee Benefits - Summary of

Employee Benefits - Summary of Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Weighted Number of Options Outstanding
Outstanding Options, Beginning Balance	1,632,334
Options Granted (in shares)	260,271
Options Exercised	(215,065)
Options Canceled or Forfeited	(8,215)
Outstanding Options, Ending Balance	1,669,325	1,632,334
Exercisable Options, Ending Balance	784,768
Weighted Average Exercise Price
Weighted Average Exercise Price, Outstanding Options, Beginning Balance	$ 70.67
Weighted Average Exercise Price, Options Granted	109.67
Weighted Average Exercise Price, Options Exercised	55.50
Weighted Average Exercise Price, Options Canceled or Forfeited	84.29
Weighted Average Exercise Price, Outstanding Options, Ending Balance	78.63	$ 70.67
Weighted Average Exercise Price, Exercisable Options	$ 67.14
Weighted Average Remaining Contractual Life
Weighted Average Remaining Contractual Life, Outstanding Options	4 years 10 months 24 days
Weighted Average Remaining Contractual Life, Exercisable Options	3 years 7 months 28 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Options Exercised	$ 12,200	$ 15,500	$ 20,000
Aggregate Intrinsic Value, Outstanding Options	56,018
Aggregate Intrinsic Value, Exercisable Options	$ 35,282

Employee Benefits - Summary o_2

Employee Benefits - Summary of Weighted Average Grant-date Assumptions and Weighted Average Fair Values (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Weighted average grant date assumptions and weighted average fair value
Weighted-average fair value of grants	$ 17.11	$ 13.24	$ 13.49
Risk-free interest rates	0.75%	0.39%	2.26%
Dividend yield	2.06%	2.30%	2.69%
Expected volatility	22.73%	22.67%	22.71%
Expected option life	4 years 11 months 19 days	4 years 11 months 15 days	4 years 11 months 15 days

Employee Benefits - Restricted

Employee Benefits - Restricted Stock Units - Additional Information (Details) - Restricted Stock Units (RSUs) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Age and period of service of the participant to be eligible for retirement	75 years
Fair value of restricted stock units vested	$ 2.2	$ 1.5	$ 0.7
Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	1 year

Employee Benefits - Schedule of

Employee Benefits - Schedule of Restricted Stock Units Activity (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2021$ / sharesshares
Number of RSUs
RSUs Nonvested, Beginning Balance | shares	47,658
RSUs Granted | shares	16,780
RSUs Reinvested | shares	1,233
RSUs Vested | shares	(19,725)
RSUs Forfeited | shares	(878)
RSUs Nonvested, Ending Balance | shares	45,068
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested, Beginning Balance | $ / shares	$ 81.53
Weighted Average Grant Date Fair Value, Granted | $ / shares	113.02
Weighted Average Grant Date Fair Value, Reinvested | $ / shares	108
Weighted Average Grant Date Fair Value, Vested | $ / shares	72.53
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	94.28
Weighted Average Grant Date Fair Value, Nonvested, Ending Balance | $ / shares	$ 97.67

Statutory Information and Div_3

Statutory Information and Dividend Restrictions - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)company	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Statutory Accounting Practices [Line Items]
Number of insurance companies | company	3
Fair value of investment in affiliate included in statutory surplus	$ 271,200	$ 238,000	$ 190,900
Cost basis of investment in affiliate included in statutory surplus	64,600
Equity	1,229,361	1,135,978	995,388	$ 806,842
Remaining unrestricted equity, liquid assets	87,900
RLI Ins.
Statutory Accounting Practices [Line Items]
Authorized control level RBC	225,100	203,900	191,000
Consolidated surplus, statutory basis	$ 1,200,000	1,100,000	1,000,000
Dividend restriction as percentage of policyholder surplus	10.00%
Payments of Ordinary Dividends	$ 70,000	110,000	59,000
Extraordinary dividend paid after seeking and receiving approval from the Illinois regulatory authorities	110,000	$ 0	$ 0
Non restricted net assets	$ 26,100

Statutory Information and Div_4

Statutory Information and Dividend Restrictions - Schedule of Selected Information for Insurance Subsidiaries (Details) - Insurance Subsidiaries - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Selected information for insurance subsidiaries
Consolidated net income, statutory basis	$ 207,550	$ 120,329	$ 129,625
Consolidated surplus, statutory basis	$ 1,240,649	$ 1,121,592	$ 1,029,671

Commitments And Contingent Li_2

Commitments And Contingent Liabilities (Details) $ in Millions	Dec. 31, 2021USD ($)
Other Assets
Fair value investments entities that calculate net asset value per share unfunded commitments	$ 20.1

Leases - Schedule of Components

Leases - Schedule of Components of Lease Expense and Other lease Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 5,131	$ 5,504	$ 5,772
Variable lease cost	1,433	1,346	1,850
Sublease income	(508)	(262)
Total lease cost	6,056	6,588	7,622
Cash paid for amounts included in measurement of lease liabilities
Operating cash flows from operating leases	5,738	5,963	5,711
ROU assets obtained in exchange for new operating lease liabilities	4,828	81	1,388
Reduction to ROU assets resulting from reduction to lease liabilities	1,042	18	$ 1,279
Other non-cash reductions to ROU assets	48	1,192
Operating lease ROU assets	$ 14,765	$ 16,200
Operating Lease, Right-of-Use Asset, Statement of Financial Position	Other assets	Other assets
Operating lease liabilities	$ 16,905	$ 19,072
Operating Lease, Liability, Statement of Financial Position	Other liabilities	Other liabilities
Weighted-average remaining lease term - operating leases	4 years 6 months 7 days	3 years 10 months 13 days
Weighted-average discount rate - operating leases	2.02%	2.32%

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Lease Payments under Non-cancellable Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Future minimum lease payments under non-cancellable leases
2022	$ 5,353
2023	4,826
2024	2,844
2025	1,481
2026	884
Thereafter	2,283
Total future minimum lease payments	17,671
Less imputed interest	(766)
Total operating lease liability	$ 16,905	$ 19,072

Operating Segment Information -

Operating Segment Information - Additional Information (Details)	Dec. 31, 2021
Maui Jim Inc.
Segment Reporting Information [Line Items]
Ownership percentage	40.00%
Prime Holdings Insurance Services, Inc. (Prime)
Segment Reporting Information [Line Items]
Ownership percentage	23.00%

Operating Segment Information_2

Operating Segment Information - Summary of Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
REVENUES
Net premiums earned	$ 980,903	$ 865,747	$ 839,111
Net investment income	68,862	67,893	68,870
Net realized gains	64,222	17,885	17,520
Net unrealized gains on equity securities	65,258	32,101	78,090
Consolidated revenue	1,179,245	983,626	1,003,591
INSURANCE EXPENSES
Loss and settlement expenses	456,602	442,884	413,416
Policy acquisition costs	317,468	286,438	288,697
Other insurance expenses	76,907	66,828	69,430
Insurance expenses	850,977	796,150	771,543
NET EARNINGS
Net underwriting income	129,926	69,597	67,568
Net investment income	68,862	67,893	68,870
Net realized gains	64,222	17,885	17,520
Net unrealized gains on equity securities	65,258	32,101	78,090
Interest on debt	(7,677)	(7,603)	(7,588)
General corporate expense	(13,330)	(10,265)	(12,686)
Equity in earnings of unconsolidated investees	37,060	20,233	20,960
Earnings before income taxes	344,321	189,841	232,734
Income tax expense	64,967	32,750	41,092
Net earnings	279,354	157,091	191,642
Casualty Segment
REVENUES
Net premiums earned	633,639	569,521	558,458
INSURANCE EXPENSES
Loss and settlement expenses	311,627	322,099	330,156
Policy acquisition costs	179,354	162,058	166,499
Other insurance expenses	47,139	40,937	41,202
NET EARNINGS
Net underwriting income	95,519	44,427	20,601
Property segment
REVENUES
Net premiums earned	231,837	183,720	164,022
INSURANCE EXPENSES
Loss and settlement expenses	129,924	111,356	73,614
Policy acquisition costs	72,008	59,926	55,986
Other insurance expenses	18,605	15,620	16,279
NET EARNINGS
Net underwriting income	11,300	(3,182)	18,143
Surety Segment
REVENUES
Net premiums earned	115,427	112,506	116,631
INSURANCE EXPENSES
Loss and settlement expenses	15,051	9,429	9,646
Policy acquisition costs	66,106	64,454	66,212
Other insurance expenses	11,163	10,271	11,949
NET EARNINGS
Net underwriting income	$ 23,107	$ 28,352	$ 28,824

Operating Segment Information_3

Operating Segment Information - Summary of Revenue by Major Product Type (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Net premiums earned	$ 980,903	$ 865,747	$ 839,111
Casualty Segment
Segment Reporting Information [Line Items]
Net premiums earned	633,639	569,521	558,458
Casualty Segment | Commercial excess and personal umbrella
Segment Reporting Information [Line Items]
Net premiums earned	219,437	178,214	140,483
Casualty Segment | General Liability
Segment Reporting Information [Line Items]
Net premiums earned	90,853	91,653	98,880
Casualty Segment | Professional services
Segment Reporting Information [Line Items]
Net premiums earned	88,855	85,196	81,329
Casualty Segment | Commercial transportation
Segment Reporting Information [Line Items]
Net premiums earned	83,352	64,624	83,213
Casualty Segment | Small commercial
Segment Reporting Information [Line Items]
Net premiums earned	64,660	63,357	55,701
Casualty Segment | Executive Products
Segment Reporting Information [Line Items]
Net premiums earned	21,873	26,509	27,088
Casualty Segment | Other casualty
Segment Reporting Information [Line Items]
Net premiums earned	64,609	59,968	71,764
Property segment
Segment Reporting Information [Line Items]
Net premiums earned	231,837	183,720	164,022
Property segment | Marine
Segment Reporting Information [Line Items]
Net premiums earned	97,745	81,852	74,887
Property segment | Commercial property
Segment Reporting Information [Line Items]
Net premiums earned	107,941	79,406	68,310
Property segment | Specialty Personal
Segment Reporting Information [Line Items]
Net premiums earned	21,385	19,596	19,316
Property segment | Other property
Segment Reporting Information [Line Items]
Net premiums earned	4,766	2,866	1,509
Surety Segment
Segment Reporting Information [Line Items]
Net premiums earned	115,427	112,506	116,631
Surety Segment | Commercial
Segment Reporting Information [Line Items]
Net premiums earned	43,738	42,872	43,553
Surety Segment | Miscellaneous
Segment Reporting Information [Line Items]
Net premiums earned	43,982	42,292	44,721
Surety Segment | Contract
Segment Reporting Information [Line Items]
Net premiums earned	$ 27,707	$ 27,342	$ 28,357

Schedule I-Summary Of Investm_2

Schedule I-Summary Of Investments-Other than Investments in Related Parties (Details) $ in Thousands	Dec. 31, 2021USD ($)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	$ 2,804,007
Fair Value	3,162,968
Amount at which shown in the balance sheet	3,162,968
Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	2,346,267
Fair Value	2,409,887
Amount at which shown in the balance sheet	2,409,887
Debt Securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	2,346,267
Fair Value	2,409,887
Amount at which shown in the balance sheet	2,409,887
U.S. government | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	127,752
Fair Value	134,554
Amount at which shown in the balance sheet	134,554
U.S. Agency | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	30,403
Fair Value	32,760
Amount at which shown in the balance sheet	32,760
Non-U.S. govt. & agency | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	8,297
Fair Value	8,481
Amount at which shown in the balance sheet	8,481
Agency MBS | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	362,861
Fair Value	367,187
Amount at which shown in the balance sheet	367,187
ABS/CMBS/MBS | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	264,273
Fair Value	264,054
Amount at which shown in the balance sheet	264,054
Corporate Debt | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	925,394
Fair Value	957,095
Amount at which shown in the balance sheet	957,095
Municipal | Available for sale securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	627,287
Fair Value	645,756
Amount at which shown in the balance sheet	645,756
Equity Securities
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	324,501
Fair Value	613,776
Amount at which shown in the balance sheet	613,776
Ind Misc & All Other
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	103,261
Fair Value	190,735
Amount at which shown in the balance sheet	190,735
ETFs (Ind/misc)
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	221,240
Fair Value	423,041
Amount at which shown in the balance sheet	423,041
Cash and Short-term Investments
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	88,804
Fair Value	88,804
Amount at which shown in the balance sheet	88,804
Other Invested Assets
SCHEDULE I - SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES
Cost	44,435
Fair Value	50,501
Amount at which shown in the balance sheet	$ 50,501

Schedule II - Condensed Financi

Schedule II - Condensed Financial Information of Registrant (Parent Company) - Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
ASSETS
Cash	$ 88,804	$ 62,217
Investment in unconsolidated investees	171,311	128,382
Fixed income:
Available-for-sale, at fair value (amortized cost of $84,823 and allowance for credit losses of $0 in 2021) (amortized cost of $60,657 and allowance for credit losses of $0 in 2020)	2,409,887	2,196,626
Property and equipment, at cost, net of accumulated depreciation of $1,697 in 2021 and $1,629 in 2020	52,161	51,406
TOTAL ASSETS	4,508,302	3,938,485
LIABILITIES
Bonds payable, long-term debt	199,700
TOTAL LIABILITIES	3,278,941	2,802,507
SHAREHOLDERS' EQUITY
Common stock ($0.01 par value) (Shares authorized - 200,000,000) (68,219,551 shares issued and 45,289,337 shares outstanding in 2021) (68,072,794 shares issued and 45,142,580 shares outstanding in 2020)	682	681
Paid-in capital	343,742	335,365
Accumulated other comprehensive earnings	49,826	108,714
Retained earnings	1,228,110	1,084,217
Deferred compensation	9,642	8,292
Treasury stock, at cost (22,930,214 shares in 2021 and 2020)	(402,641)	(401,291)
TOTAL SHAREHOLDERS' EQUITY	1,229,361	1,135,978	$ 995,388	$ 806,842
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	4,508,302	3,938,485
Parent Company
ASSETS
Cash	1,433	381
Accounts receivable, affiliates	848
Investments in subsidiaries	1,197,997	1,148,342
Investment in unconsolidated investees	113,052	90,893
Fixed income:
Available-for-sale, at fair value (amortized cost of $84,823 and allowance for credit losses of $0 in 2021) (amortized cost of $60,657 and allowance for credit losses of $0 in 2020)	86,483	64,211
Property and equipment, at cost, net of accumulated depreciation of $1,697 in 2021 and $1,629 in 2020	1,711	1,779
Income taxes receivable - current	211	1,500
Other assets	2,907	895
TOTAL ASSETS	1,404,642	1,308,001
LIABILITIES
Accounts payable, affiliates		2,556
Income taxes - deferred	21,067	16,988
Bonds payable, long-term debt	149,676	149,489
Interest payable, long-term debt	2,153	2,153
Other liabilities	2,385	837
TOTAL LIABILITIES	175,281	172,023
SHAREHOLDERS' EQUITY
Common stock ($0.01 par value) (Shares authorized - 200,000,000) (68,219,551 shares issued and 45,289,337 shares outstanding in 2021) (68,072,794 shares issued and 45,142,580 shares outstanding in 2020)	682	681
Paid-in capital	343,742	335,365
Accumulated other comprehensive earnings	49,826	108,714
Retained earnings	1,228,110	1,084,217
Deferred compensation	9,642	8,292
Treasury stock, at cost (22,930,214 shares in 2021 and 2020)	(402,641)	(401,291)
TOTAL SHAREHOLDERS' EQUITY	1,229,361	1,135,978
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 1,404,642	$ 1,308,001

Schedule II - Condensed Finan_2

Schedule II - Condensed Financial Information of Registrant (Parent Company) - Balance Sheets (Parenthetical) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Condensed Balance Sheet Statements Captions [Line Items]
Available-for-sale, amortized cost	$ 2,346,267	$ 2,061,467
Available-for-sale, allowance for credit losses	441	397
Property and equipment, accumulated depreciation	$ 75,236	$ 68,682
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	68,219,551	68,072,794
Common stock, shares outstanding (in shares)	45,289,337	45,142,580
Treasury stock, shares (in shares)	22,930,214	22,930,214
Parent Company
Condensed Balance Sheet Statements Captions [Line Items]
Available-for-sale, amortized cost	$ 84,823	$ 60,657
Available-for-sale, allowance for credit losses	0	0
Property and equipment, accumulated depreciation	$ 1,697	$ 1,629
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	68,219,551	68,072,794
Common stock, shares outstanding (in shares)	45,289,337	45,142,580
Treasury stock, shares (in shares)	22,930,214	22,930,214

Schedule II - Condensed Finan_3

Schedule II - Condensed Financial Information of Registrant (Parent Company) - Condensed Statements of Earnings and Comprehensive Earnings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Statement Of Income Captions [Line Items]
Net investment income	$ 68,862	$ 67,893	$ 68,870
Net realized gains	64,222	17,885	17,520
Equity in earnings of unconsolidated investees	37,060	20,233	20,960
Interest on debt	(7,677)	(7,603)	(7,588)
Earnings before income taxes	344,321	189,841	232,734
Income tax expense	64,967	32,750	41,092
Net earnings	279,354	157,091	191,642
Unrealized gains (losses) on securities:
Net current period other comprehensive earnings (loss)	(58,888)	56,219	67,045
Comprehensive earnings	220,466	213,310	258,687
Parent Company
Condensed Statement Of Income Captions [Line Items]
Net investment income	2,102	1,412	1,656
Net realized gains	(625)	501	463
Equity in earnings of unconsolidated investees	22,786	10,368	13,592
Selling, general and administrative expenses	(13,330)	(10,265)	(12,686)
Interest on debt	(7,616)	(7,603)	(7,588)
Earnings before income taxes	3,317	(5,587)	(4,563)
Income tax expense	(1,585)	(2,885)	(4,989)
Net earnings (loss) before equity in net earnings of subsidiaries	4,902	(2,702)	426
Equity in net earnings of subsidiaries	274,452	159,793	191,216
Net earnings	279,354	157,091	191,642
Unrealized gains (losses) on securities:
Unrealized holding gains (losses) arising during the period	(1,996)	994	1,727
Less: reclassification adjustment for (gains) losses included in net earnings	500	(390)	(365)
Other comprehensive earnings (loss) - parent only	(1,496)	604	1,362
Equity in other comprehensive earnings (loss) of subsidiaries/investees	(57,392)	55,615	65,683
Net current period other comprehensive earnings (loss)	(58,888)	56,219	67,045
Comprehensive earnings	$ 220,466	$ 213,310	$ 258,687

Schedule II - Condensed Finan_4

Schedule II - Condensed Financial Information of Registrant (Parent Company) - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net earnings	$ 279,354	$ 157,091	$ 191,642
Adjustments to reconcile net losses to net cash provided by (used in) operating activities:
Net realized (gains) losses	(64,222)	(17,885)	(17,520)
Depreciation	7,394	7,432	8,164
Other items, net	14,141	10,460	25,341
Changes in investment in unconsolidated investees:
Undistributed earnings	(37,060)	(20,233)	(20,960)
Dividends received		4,675	13,200
Net cash provided by operating activities	384,905	263,259	276,917
Purchase of:
Fixed income securities, available-for-sale	(733,811)	(518,362)	(539,726)
Other	(11,428)	(12,851)	(22,751)
Sale of:
Fixed income securities, available-for-sale	63,811	84,587	196,558
Call or maturity of:
Fixed income, available-for-sale	376,750	283,107	201,383
Net cash used in investing activities	(274,826)	(167,987)	(184,753)
Cash flows from financing activities:
Proceeds from stock option exercises	1,838	8,648	9,490
Net cash used in financing activities	(83,492)	(79,258)	(76,101)
Net increase in cash	26,587	16,014	16,063
Cash at beginning of year	62,217	46,203	30,140
Cash at end of year	88,804	62,217	46,203
Parent Company
Cash flows from operating activities:
Net earnings	4,902	(2,702)	426
Adjustments to reconcile net losses to net cash provided by (used in) operating activities:
Net realized (gains) losses	625	(501)	(463)
Depreciation	68	67	68
Other items, net	3,966	2,270	2,487
Change in:
Affiliate balances receivable/payable	(3,404)	1,246	1,180
Federal income taxes	5,901	1,399	(1,673)
Changes in investment in unconsolidated investees:
Undistributed earnings	(22,786)	(10,368)	(13,592)
Dividends received			13,200
Net cash provided by operating activities	(10,728)	(8,589)	1,633
Purchase of:
Fixed income securities, available-for-sale	(33,373)	(24,950)	(2,507)
Other	(2,904)	(346)
Sale of:
Fixed income securities, available-for-sale	5,306	3,767	14,273
Other	1,245
Call or maturity of:
Fixed income, available-for-sale	2,878	3,492	29,501
Cash dividends received-subsidiaries	180,000	110,000	34,003
Net cash used in investing activities	153,152	91,963	75,270
Cash flows from financing activities:
Proceeds from stock option exercises	1,838	8,648	9,490
Cash dividends paid	(147,422)	(95,793)	(93,315)
Other	4,212	3,802	4,058
Net cash used in financing activities	(141,372)	(83,343)	(79,767)
Net increase in cash	1,052	31	(2,864)
Cash at beginning of year	381	350	3,214
Cash at end of year	$ 1,433	$ 381	$ 350

Schedule II - Condensed Finan_5

Schedule II - Condensed Financial Information of Registrant (Parent Company) - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Cash Flow Statements Captions [Line Items]
Interest paid	$ 7.3	$ 7.3	$ 7.3
Parent Company
Condensed Cash Flow Statements Captions [Line Items]
Interest paid	$ 7.3	$ 7.3	$ 7.3

Schedule III-Supplementary In_2

Schedule III-Supplementary Insurance Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Supplementary insurance information
Deferred policy acquisition costs	$ 103,553	$ 88,425	$ 85,044
Unpaid losses and settlement expenses, gross	2,043,555	1,750,049	1,574,352
Unearned premiums, gross	680,444	586,386	540,213
Net premiums earned	980,903	865,747	839,111
Incurred losses and settlement expenses
Current accident year	582,065	543,937	488,700
Prior accident years	(125,463)	(101,053)	(75,284)
Policy acquisition costs	317,468	286,438	288,697
Other operating expenses	76,907	66,828	69,430
Net premiums written	1,057,533	892,088	860,337
Casualty Segment
Supplementary insurance information
Deferred policy acquisition costs	55,760	48,255	47,805
Unpaid losses and settlement expenses, gross	1,760,469	1,567,544	1,435,619
Unearned premiums, gross	438,248	385,736	354,118
Net premiums earned	633,639	569,521	558,458
Incurred losses and settlement expenses
Current accident year	420,259	397,174	392,653
Prior accident years	(108,632)	(75,075)	(62,497)
Policy acquisition costs	179,354	162,058	166,499
Other operating expenses	47,139	40,937	41,202
Net premiums written	674,709	583,244	564,979
Property segment
Supplementary insurance information
Deferred policy acquisition costs	25,764	19,655	17,057
Unpaid losses and settlement expenses, gross	196,369	150,008	100,000
Unearned premiums, gross	168,209	131,274	116,624
Net premiums earned	231,837	183,720	164,022
Incurred losses and settlement expenses
Current accident year	140,905	124,375	78,075
Prior accident years	(10,981)	(13,019)	(4,461)
Policy acquisition costs	72,008	59,926	55,986
Other operating expenses	18,605	15,620	16,279
Net premiums written	262,816	196,603	181,974
Surety Segment
Supplementary insurance information
Deferred policy acquisition costs	22,029	20,515	20,182
Unpaid losses and settlement expenses, gross	86,717	32,497	38,733
Unearned premiums, gross	73,987	69,376	69,471
Net premiums earned	115,427	112,506	116,631
Incurred losses and settlement expenses
Current accident year	20,901	22,388	17,972
Prior accident years	(5,850)	(12,959)	(8,326)
Policy acquisition costs	66,106	64,454	66,212
Other operating expenses	11,163	10,271	11,949
Net premiums written	$ 120,008	$ 112,241	$ 113,384

Schedule IV-Reinsurance (Detail

Schedule IV-Reinsurance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
RLI Insurance Group Premiums earned
Direct amount	$ 1,222,346	$ 1,062,608	$ 981,121
Ceded to other companies	272,393	224,512	182,183
Assumed from other companies	30,950	27,651	40,173
Net	$ 980,903	$ 865,747	$ 839,111
Percentage of amount assumed to net	3.20%	3.20%	4.80%
Casualty Segment
RLI Insurance Group Premiums earned
Direct amount	$ 788,741	$ 690,718	$ 641,159
Ceded to other companies	185,433	148,271	122,452
Assumed from other companies	30,331	27,074	39,751
Net	$ 633,639	$ 569,521	$ 558,458
Percentage of amount assumed to net	4.80%	4.80%	7.10%
Property segment
RLI Insurance Group Premiums earned
Direct amount	$ 310,630	$ 253,781	$ 217,657
Ceded to other companies	79,094	70,398	53,810
Assumed from other companies	301	337	175
Net	$ 231,837	$ 183,720	$ 164,022
Percentage of amount assumed to net	0.10%	0.20%	0.10%
Surety segment
RLI Insurance Group Premiums earned
Direct amount	$ 122,975	$ 118,109	$ 122,305
Ceded to other companies	7,866	5,843	5,921
Assumed from other companies	318	240	247
Net	$ 115,427	$ 112,506	$ 116,631
Percentage of amount assumed to net	0.30%	0.20%	0.20%

Schedule V-Valuation and Qual_2

Schedule V-Valuation and Qualifying Accounts (Details) - Allowance for Uncollectible Reinsurance - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Valuation allowances and qualifying accounts
Balance at beginning of period	$ 24,539	$ 25,066	$ 25,911
Amounts charged to expense	2,863	(522)	(647)
Amounts recovered (written off)	(159)	(5)	(198)
Balance at end of period	$ 27,243	$ 24,539	$ 25,066

Schedule VI-Supplementary Inf_2

Schedule VI-Supplementary Information Concerning Property-Casualty Insurance Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Claims and claim adjustment expenses incurred related to:
Current accident year	$ 582,065	$ 543,937	$ 488,700
Prior accident years	(125,463)	(101,053)	(75,284)
Amortization of deferred acquisition costs	317,468	286,438	288,697
Consolidated Property-Casualty Insurance Operations
Supplemental Information For Property Casualty Insurance Underwriters [Line Items]
Deferred policy acquisition costs	103,553	88,425	85,044
Claims and claim adjustment expense reserves	2,043,555	1,750,049	1,574,352
Unearned premiums, gross	680,444	586,386	540,213
Net premiums earned	980,903	865,747	839,111
Net investment income	68,862	67,893	68,870
Claims and claim adjustment expenses incurred related to:
Current accident year	582,065	543,937	488,700
Prior accident years	(125,463)	(101,053)	(75,284)
Amortization of deferred acquisition costs	317,468	286,438	288,697
Paid claims and claims adjustment expenses	327,453	325,054	319,930
Net premiums written	$ 1,057,533	$ 892,088	$ 860,337