Selective Insurance (SIGI) 10-Q 3 Aug 23 2023 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Jul. 31, 2023
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-33067
Entity Registrant Name	SELECTIVE INSURANCE GROUP, INC
Entity Incorporation, State or Country Code	NJ
Entity Tax Identification Number	22-2168890
Entity Address, Address Line One	40 Wantage Avenue
Entity Address, City or Town	Branchville
Entity Address, State or Province	NJ
Entity Address, Postal Zip Code	07890
City Area Code	(973)
Local Phone Number	948-3000
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		60,566,856
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Entity Central Index Key	0000230557
Current Fiscal Year End Date	--12-31
Noncumulative Preferred Stock
Document Information [Line Items]
Title of 12(b) Security	Depositary Shares, each representing a 1/1,000th interest in a share of 4.60% Non-Cumulative Preferred Stock, Series B, without par value
Trading Symbol	SIGIP
Security Exchange Name	NASDAQ
Common Stock [Member]
Document Information [Line Items]
Title of 12(b) Security	Common Stock, par value $2 per share
Trading Symbol	SIGI
Security Exchange Name	NASDAQ

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
ASSETS
Fixed income securities, held-to-maturity - at carrying value	$ 23,676	$ 31,157
Less: allowance for credit losses	0	0
Fixed income securities, held-to-maturity, net of allowance for credit losses	23,676	31,157
Fixed income securities, available-for-sale - at fair value	7,032,348	6,612,107
Commercial mortgage loans - at carrying value	175,538	149,305
Less: allowance for credit losses	(177)	(116)
Commercial mortgage loans, net of allowance for credit losses	175,361	149,189
Equity securities - at fair value	121,640	162,000
Short-term investments	319,456	440,456
Alternative investments	389,173	371,316
Other investments	71,545	71,244
Total investments (Note 4 and 5)	8,133,199	7,837,469
Cash	354	26
Restricted cash	20,904	25,183
Accrued investment income	59,441	59,167
Premiums receivable	1,304,394	1,101,787
Less: allowance for credit losses (Note 6)	(17,900)	(16,100)
Premiums receivable, net of allowance for credit losses	1,286,494	1,085,687
Reinsurance recoverable, gross	648,591	784,410
Less: allowance for credit losses (Note 7)	(1,800)	(1,600)
Reinsurance recoverable, net of allowance for credit losses	646,791	782,810
Prepaid reinsurance premiums	190,425	172,371
Current federal income tax	0	3,545
Deferred federal income tax	171,915	172,733
Property and equipment - at cost, net of accumulated depreciation and amortization	81,255	84,306
Deferred policy acquisition costs	413,813	368,624
Goodwill	7,849	7,849
Other assets	204,800	202,491
Total assets	11,217,240	10,802,261
Liabilities:
Reserve for loss and loss expense (Note 8)	5,177,023	5,144,821
Unearned premiums	2,251,024	1,992,781
Long-term debt	503,622	504,676
Current federal income tax	2,555	0
Accrued salaries and benefits	91,993	115,185
Other liabilities	519,631	517,234
Total liabilities	8,545,848	8,274,697
Stockholders' Equity:
Preferred stock of $0 par value per share: Authorized shares 5,000,000; Issued shares: 8,000 with $25,000 liquidation preference per share - 2023 and 2022	200,000	200,000
Common stock of $2 par value per share: Authorized shares 360,000,000; Issued: 105,148,165 - 2023; 104,847,111 - 2022	210,296	209,694
Additional paid-in capital	512,040	493,488
Retained earnings	2,859,569	2,749,703
Accumulated other comprehensive income (loss) (Note 11)	(475,722)	(498,042)
Treasury stock, at cost (shares: 44,582,682 - 2023; 44,508,211 - 2022)	(634,791)	(627,279)
Total stockholders' equity	2,671,392	2,527,564
Commitments and contingencies
Total liabilities and stockholders' equity	$ 11,217,240	$ 10,802,261

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenues:
Net premiums earned	$ 942,150	$ 834,439	$ 1,844,486	$ 1,646,722
Net investment income earned	97,696	70,222	189,202	142,824
Net realized and unrealized investment gains (losses)	(5,426)	(42,880)	(2,082)	(83,232)
Other income	6,104	3,037	8,738	4,566
Total revenues	1,040,524	864,818	2,040,344	1,710,880
Expenses:
Loss and loss expense incurred	646,130	524,868	1,213,568	1,019,104
Amortization of deferred policy acquisition costs	194,793	173,381	384,554	343,138
Other insurance expenses	108,857	101,514	217,445	195,504
Interest expense	7,258	7,252	14,424	14,420
Corporate expenses	9,329	7,899	21,437	18,920
Total expenses	966,367	814,914	1,851,428	1,591,086
Income before federal income tax	74,157	49,904	188,916	119,794
Federal income tax expense:
Current	17,366	9,692	42,871	26,870
Deferred	(1,817)	692	(5,137)	(2,926)
Total federal income tax expense	15,549	10,384	37,734	23,944
Net income	58,608	39,520	151,182	95,850
Preferred stock dividends	2,300	2,300	4,600	4,600
Net income available to common stockholders	$ 56,308	$ 37,220	$ 146,582	$ 91,250
Earnings per common share (not in thousands):
Earnings per common share - net income available to common stockholders - Basic	$ 0.93	$ 0.62	$ 2.42	$ 1.51
Earnings per common share - net income available to common stockholders - Diluted	$ 0.92	$ 0.61	$ 2.41	$ 1.50

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net income	$ 58,608	$ 39,520	$ 151,182	$ 95,850
Unrealized holding gains (losses) arising during period	(47,937)	(176,093)	4,142	(382,941)
Unrealized gains (losses) on securities with credit loss recognized in earnings	(4,764)	(57,427)	12,957	(125,857)
Amounts reclassified into net income: Held-to-maturity securities	0	0	0	1
Amounts reclassified into net income: Net realized (gains) losses on disposals and losses on intent-to-sell AFS securities	7,413	14,354	12,235	26,987
Amounts reclassified into net income: Credit loss (benefit) expense	(683)	12,261	(8,210)	29,682
Total unrealized gains (losses) on investment securities	(45,971)	(206,905)	21,124	(452,128)
Amount reclassified into net income: Net actuarial loss	598	330	1,196	659
Total defined benefit pension and post-retirement plans, Net	598	330	1,196	659
Other comprehensive income (loss)	(45,373)	(206,575)	22,320	(451,469)
Comprehensive income (loss)	$ 13,235	$ (167,055)	$ 173,502	$ (355,619)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional paid-in capital [Member]	Retained Earnings [Member]	Accumulated other comprehensive income (loss) [Member]	Treasury stock [Member]
Preferred stock, shares outstanding	8,000
Beginning of period at Dec. 31, 2021		$ 200,000	$ 208,902	$ 464,347	$ 2,603,472	$ 115,099	$ (608,935)
Issuance of preferred stock		0
Dividend reinvestment plan			23	887
Stock purchase and compensation plans			581	16,146
Net income	$ 95,850				95,850
Dividends to preferred stockholders					(4,600)
Dividends to common stockholders					(34,138)
Other comprehensive income (loss)	(451,469)					(451,469)
Acquisition of treasury stock - share repurchase authorization							(6,492)
Acquisition of treasury stock - shares acquired related to employee-share based compensation plans							(5,583)
End of period at Jun. 30, 2022	$ 2,594,090	$ 200,000	209,506	481,380	2,660,584	(336,370)	(621,010)
Dividends declared per preferred share (in dollars per share)	$ 575
Dividends declared per common share (in dollars per share)	$ 0.56
Issuance of preferred stock, shares		0
Common stock, shares outstanding, beginning of period at Dec. 31, 2021	60,184,382
Dividend reinvestment plan, shares	11,505
Stock purchase and compensation plan, shares	290,687
Acquisition of treasury stock, share repurchase authorization, shares	(86,059)
Acquisition of treasury stock - shares acquired related to employee share-based compensation plans, shares	(72,781)
Common stock, shares outstanding, end of period at Jun. 30, 2022	60,327,734
Preferred stock, shares outstanding	8,000
Beginning of period at Mar. 31, 2022		$ 200,000	209,336	472,790	2,640,437	(129,795)	(614,527)
Issuance of preferred stock		0
Dividend reinvestment plan			12	444
Stock purchase and compensation plans			158	8,146
Net income	$ 39,520				39,520
Dividends to preferred stockholders					(2,300)
Dividends to common stockholders					(17,073)
Other comprehensive income (loss)	(206,575)					(206,575)
Acquisition of treasury stock - share repurchase authorization							(6,416)
Acquisition of treasury stock - shares acquired related to employee-share based compensation plans							(67)
End of period at Jun. 30, 2022	$ 2,594,090	$ 200,000	209,506	481,380	2,660,584	(336,370)	(621,010)
Dividends declared per preferred share (in dollars per share)	$ 287.50
Dividends declared per common share (in dollars per share)	$ 0.28
Issuance of preferred stock, shares		0
Common stock, shares outstanding, beginning of period at Mar. 31, 2022	60,335,472
Dividend reinvestment plan, shares	5,864
Stock purchase and compensation plan, shares	72,245
Acquisition of treasury stock, share repurchase authorization, shares	(85,059)
Acquisition of treasury stock - shares acquired related to employee share-based compensation plans, shares	(788)
Common stock, shares outstanding, end of period at Jun. 30, 2022	60,327,734
Preferred stock, shares outstanding	8,000
Preferred stock, shares outstanding	8,000
Beginning of period at Dec. 31, 2022	$ 2,527,564	$ 200,000	209,694	493,488	2,749,703	(498,042)	(627,279)
Issuance of preferred stock		0
Dividend reinvestment plan			19	908
Stock purchase and compensation plans			583	17,644
Net income	151,182				151,182
Dividends to preferred stockholders					(4,600)
Dividends to common stockholders					(36,716)
Other comprehensive income (loss)	22,320					22,320
Acquisition of treasury stock - share repurchase authorization							0
Acquisition of treasury stock - shares acquired related to employee-share based compensation plans							(7,512)
End of period at Jun. 30, 2023	$ 2,671,392	$ 200,000	210,296	512,040	2,859,569	(475,722)	(634,791)
Dividends declared per preferred share (in dollars per share)	$ 575
Dividends declared per common share (in dollars per share)	$ 0.60
Issuance of preferred stock, shares		0
Common stock, shares outstanding, beginning of period at Dec. 31, 2022	60,338,900
Dividend reinvestment plan, shares	9,315
Stock purchase and compensation plan, shares	291,739
Acquisition of treasury stock, share repurchase authorization, shares	0
Acquisition of treasury stock - shares acquired related to employee share-based compensation plans, shares	(74,471)
Common stock, shares outstanding, end of period at Jun. 30, 2023	60,565,483
Preferred stock, shares outstanding	8,000
Beginning of period at Mar. 31, 2023		$ 200,000	210,149	502,713	2,821,613	(430,349)	(634,722)
Issuance of preferred stock		0
Dividend reinvestment plan			10	449
Stock purchase and compensation plans			137	8,878
Net income	$ 58,608				58,608
Dividends to preferred stockholders					(2,300)
Dividends to common stockholders					(18,352)
Other comprehensive income (loss)	(45,373)					(45,373)
Acquisition of treasury stock - share repurchase authorization							0
Acquisition of treasury stock - shares acquired related to employee-share based compensation plans							(69)
End of period at Jun. 30, 2023	$ 2,671,392	$ 200,000	$ 210,296	$ 512,040	$ 2,859,569	$ (475,722)	$ (634,791)
Dividends declared per preferred share (in dollars per share)	$ 287.50
Dividends declared per common share (in dollars per share)	$ 0.30
Issuance of preferred stock, shares		0
Common stock, shares outstanding, beginning of period at Mar. 31, 2023	60,492,586
Dividend reinvestment plan, shares	4,665
Stock purchase and compensation plan, shares	68,923
Acquisition of treasury stock, share repurchase authorization, shares	0
Acquisition of treasury stock - shares acquired related to employee share-based compensation plans, shares	(691)
Common stock, shares outstanding, end of period at Jun. 30, 2023	60,565,483
Preferred stock, shares outstanding	8,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating Activities
Net income	$ 151,182	$ 95,850
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	17,179	21,998
Stock-based compensation expense	12,886	11,886
Undistributed gains of equity method investments	(13,478)	(12,890)
Distributions in excess of current year income of equity method investments	6,698	20,252
Net realized and unrealized (gains) losses	2,082	83,232
Loss (gain) on disposal of fixed assets	5	(1)
Changes in assets and liabilities:
Increase in reserve for loss and loss expense, net of reinsurance recoverable	168,221	169,114
Increase in unearned premiums, net of prepaid reinsurance	240,189	173,817
Decrease (increase) in net federal income taxes	1,006	(17,665)
Increase in premiums receivable	(200,807)	(172,231)
Increase in deferred policy acquisition costs	(45,189)	(32,464)
Increase in accrued investment income	(264)	(2,116)
Decrease in accrued salaries and benefits	(23,192)	(18,530)
Increase in other assets	(4,667)	(25,598)
Decrease in other liabilities	(18,205)	(51,171)
Net cash provided by (used in) operating activities	293,646	243,483
Investing Activities
Purchases of fixed income securities, held-to-maturity	0	(5,000)
Purchases of fixed income securities, available-for-sale	(1,562,206)	(1,478,298)
Purchases of commercial mortgage loans	(27,201)	(48,926)
Purchases of equity securities	(8,373)	(18,209)
Purchases of alternative investments and other investments	(21,161)	(32,179)
Purchases of short-term investments	(2,422,123)	(2,041,614)
Sales of fixed income securities, available-for-sale	959,248	705,039
Proceeds from commercial mortgage loans	968	7,504
Sales of short-term investments	2,543,683	2,200,624
Redemption and maturities of fixed income securities, held-to-maturity	7,481	1,684
Redemption and maturities of fixed income securities, available-for-sale	227,884	392,648
Sales of equity securities	51,763	85,162
Sales of other investments	892	2,156
Distributions from alternative investments and other investments	5,130	9,013
Purchases of property and equipment	(9,549)	(14,101)
Net cash provided by (used in) investing activities	(253,564)	(234,497)
Financing Activities
Dividends to preferred stockholders	(4,600)	(4,600)
Dividends to common stockholders	(35,385)	(32,886)
Acquisition of treasury stock	(7,512)	(12,075)
Net proceeds from stock purchase and compensation plans	4,695	4,280
Proceeds from borrowings	20,000	35,000
Repayments of borrowings	(20,000)	(35,000)
Repayments of finance lease obligations	(1,231)	(1,202)
Net cash provided by (used in) financing activities	(44,033)	(46,483)
Net increase (decrease) in cash and restricted cash	(3,951)	(37,497)
Cash and restricted cash, beginning of period	25,209	45,063
Cash and restricted cash, end of period	$ 21,258	$ 7,566

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Fixed income securities, held-to-maturity, fair value	$ 22,356	$ 29,837
Fixed income securities, available-for-sale, allowance for credit loss	31,425	45,721
Fixed income securities, available-for-sale, amortized cost	7,564,942	7,185,754
Commercial mortgage loans, fair value	163,068	139,243
Equity securities, cost	118,898	167,431
Property and equipment, accumulated depreciation and amortization	$ 262,013	$ 251,209
Preferred stock, shares outstanding	8,000	8,000
Preferred Stock [Member]
Preferred stock, par or stated value (in dollars per share)	$ 0	$ 0
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	8,000	8,000
Preferred stock, shares outstanding	8,000	8,000
Preferred stock, liquidation preference (in dollars per share)	$ 25,000	$ 25,000
Common Stock [Member]
Common stock, par or stated value (in dollars per share)	$ 2	$ 2
Common stock, shares authorized	360,000,000	360,000,000
Common stock, shares issued	105,148,165	104,847,111
Treasury stock [Member]
Treasury stock, shares	44,582,682	44,508,211

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2023
Basis of Presentation And Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of PresentationThe words "Company,” “we,” “us,” or “our” refer to Selective Insurance Group, Inc. (the "Parent") and its subsidiaries, except as expressly indicated or the context requires otherwise. We have prepared our interim unaudited consolidated financial statements (“Financial Statements”) in conformity with (i) United States ("U.S.") generally accepted accounting principles (“GAAP”), and (ii) the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. These require management to make estimates and assumptions that affect the reported financial statement balances and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. All significant intercompany accounts and transactions are eliminated in consolidation.Our Financial Statements reflect all adjustments that, in our opinion, are normal, recurring, and necessary for a fair presentation of our results of operations and financial condition. Our Financial Statements cover the second quarters ended June 30, 2023 (“Second Quarter 2023”) and June 30, 2022 (“Second Quarter 2022”), and the six-month periods ended June 30, 2023 ("Six Months 2023") and June 30, 2022 ("Six Months 2022"). Our Financial Statements do not include all information and disclosures required by GAAP and the SEC for audited annual financial statements. Because interim period results of operations are not necessarily indicative of full-year results, our Financial Statements should be read in conjunction with the consolidated financial statements in our Annual Report on Form 10-K for the year ended December 31, 2022 (“2022 Annual Report”) filed with the SEC.

Accounting Pronouncements

Accounting Pronouncements	6 Months Ended
	Jun. 30, 2023
Accounting Policies [Abstract]
Accounting Pronouncements	Adoption of Accounting Pronouncements In March 2020, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2020-04, Reference Rate Reform (Topic 848) — Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”). ASU 2020-04 provides optional expedients and exceptions to the GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burdens related to the market transition away from the London Interbank Offered Rate ("LIBOR") and other interbank offered rates to alternative reference rates. Companies can elect to adopt ASU 2020-04 as of the beginning of the interim period that includes March 2020, or any date thereafter through December 31, 2024, as permitted by the newly issued ASU 2022-06, Reference Rate Reform (Topic 848) — Deferral of the Sunset Date of Topic 848 . We adopted this guidance in the first quarter of 2023. We are not required to measure the effect of adoption on our financial position, cash flows, or net income because the guidance provides relief from accounting for the effects of the change to a replacement rate. Pronouncements to be effective in the future In June 2022, the FASB issued ASU 2022-03 , Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions (“ASU 2022-03”). ASU 2022-03 clarifies that a contractual sales restriction on an equity security is not considered when determining the security's fair value. This ASU was issued to eliminate diversity in practice by clarifying that contractual arrangements restricting an entity's ability to sell the security for a certain period of time is a characteristic of the reporting entity and should not be contemplated when determining the security's fair value. ASU 2022-03 requires new disclosures that provide investors with information about the restriction, including the nature and remaining duration of the restriction. The ASU is effective for annual periods beginning after December 15, 2023, including interim periods within those annual periods. Early adoption is permitted. We are currently evaluating the impact of this guidance. In March 2023, the FASB issued ASU 2023-02, Investments — Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method ("ASU 2023-02"). This ASU allows companies to elect to account for qualifying tax equity investments, regardless of the tax credit program from which the income tax credits are received, using the proportional amortization method if certain conditions are met. Companies were previously permitted to apply the proportional amortization method only to qualifying tax equity investments in low-income-housing tax credit structures. ASU 2023-02 extends the application of the proportional amortization method to qualifying tax equity investments that generate tax credits through other programs. It also requires new disclosures that provide a better understanding of the nature of the tax equity investments and the effect the tax equity investments and related income tax credits and other income tax benefits have on a company's financial position and results of operations. The ASU is effective for annual periods beginning after December 15, 2023, including interim periods within those fiscal years. Early adoption is permitted in any interim period. We are currently evaluating the impact of this guidance.

Statements of Cash Flows

Statements of Cash Flows	6 Months Ended
	Jun. 30, 2023
Supplemental Cash Flow Information [Abstract]
Statements of Cash Flows	Statements of Cash Flows Supplemental cash flow information was as follows: Six Months ended June 30, ($ in thousands) 2023 2022 Cash paid (received) during the period for: Interest $ 14,164 14,240 Federal income tax 34,000 40,200 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases 4,038 4,086 Operating cash flows from financing leases 20 20 Financing cash flows from finance leases 1,231 1,202 Non-cash items: Corporate actions related to fixed income securities, available-for-sale ("AFS") 1 23,150 17,287 Conversion of AFS fixed income securities to equity securities — 1,463 Assets acquired under finance lease arrangements — 41 Assets acquired under operating lease arrangements 4,509 5,781 Non-cash purchase of property and equipment — 17 1 Examples of corporate actions include like-kind exchanges, non-cash acquisitions, and stock splits. The following table provides a reconciliation of cash and restricted cash reported within the Consolidated Balance Sheets that equate to the amount reported in the Consolidated Statements of Cash Flows: ($ in thousands) June 30, 2023 December 31, 2022 Cash $ 354 26 Restricted cash 20,904 25,183 Total cash and restricted cash shown in the Consolidated Statements of Cash Flows $ 21,258 25,209 Amounts in restricted cash represent cash received from the National Flood Insurance Program ("NFIP") that can only be used to pay flood claims under the Write Your Own program.

Investments

Investments	6 Months Ended
	Jun. 30, 2023
Investments [Abstract]
Investments	Investments (a) Information regarding our AFS securities as of June 30, 2023 and December 31, 2022, were as follows: June 30, 2023 Cost/ Allowance for Credit Losses Unrealized Unrealized Fair ($ in thousands) AFS fixed income securities: U.S. government and government agencies $ 313,965 — — (20,943) 293,022 Foreign government 11,171 (34) — (1,318) 9,819 Obligations of states and political subdivisions 694,734 (769) 1,607 (37,544) 658,028 Corporate securities 2,585,819 (16,149) 4,964 (189,664) 2,384,970 Collateralized loan obligations ("CLO") and other asset-backed securities ("ABS") 1,739,788 (2,915) 3,353 (105,957) 1,634,269 Residential mortgage-backed securities ("RMBS") 1,520,170 (11,550) 1,024 (101,809) 1,407,835 Commercial mortgage-backed securities ("CMBS") 699,295 (8) 162 (55,044) 644,405 Total AFS fixed income securities $ 7,564,942 (31,425) 11,110 (512,279) 7,032,348 December 31, 2022 Cost/ Allowance for Credit Losses Unrealized Unrealized Fair ($ in thousands) AFS fixed income securities: U.S. government and government agencies $ 209,528 — 37 (20,326) 189,239 Foreign government 11,199 (284) — (1,307) 9,608 Obligations of states and political subdivisions 965,231 (1,024) 1,812 (48,001) 918,018 Corporate securities 2,558,655 (30,330) 3,509 (196,809) 2,335,025 CLO and other ABS 1,607,660 (2,375) 2,408 (121,720) 1,485,973 RMBS 1,169,546 (11,597) 1,148 (99,265) 1,059,832 CMBS 663,935 (111) 348 (49,760) 614,412 Total AFS fixed income securities $ 7,185,754 (45,721) 9,262 (537,188) 6,612,107 The following tables provide a roll forward of the allowance for credit losses on our AFS fixed income securities for the indicated periods: Quarter ended June 30, 2023 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 36 — — (2) — — 34 Obligations of states and political subdivisions 737 67 — (35) — — 769 Corporate securities 16,756 1,438 — (1,070) (939) (36) 16,149 CLO and other ABS 3,895 622 — (1,595) (7) — 2,915 RMBS 11,740 1 — (50) (141) — 11,550 CMBS 390 — — (240) (142) — 8 Total AFS fixed income securities $ 33,554 2,128 — (2,992) (1,229) (36) 31,425 Quarter ended June 30, 2022 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 150 117 — 12 (14) — 265 Obligations of states and political subdivisions 1,991 534 — (1,166) (153) — 1,206 Corporate securities 23,066 8,323 — 5,732 (1,944) (105) 35,072 CLO and other ABS 2,283 530 — 819 (9) — 3,623 RMBS 10,029 173 — 507 (93) — 10,616 CMBS 80 — — (62) — — 18 Total AFS fixed income securities $ 37,599 9,677 — 5,842 (2,213) (105) 50,800 Six Months ended June 30, 2023 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 284 — — (250) — — 34 Obligations of states and political subdivisions 1,024 67 — (239) (83) — 769 Corporate securities 30,330 4,141 — (14,884) (3,387) (51) 16,149 CLO and other ABS 2,375 677 — (127) (10) — 2,915 RMBS 11,597 8 — 174 (229) — 11,550 CMBS 111 1 — 39 (143) — 8 Total AFS fixed income securities $ 45,721 4,894 — (15,287) (3,852) (51) 31,425 Six Months ended June 30, 2022 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 46 236 — (3) (14) — 265 Obligations of states and political subdivisions 137 1,237 — (4) (164) — 1,206 Corporate securities 6,682 28,243 — 4,542 (3,191) (1,204) 35,072 CLO and other ABS 939 2,058 — 637 (11) — 3,623 RMBS 1,909 174 8,318 443 (228) — 10,616 CMBS 11 17 — (10) — — 18 Total AFS fixed income securities $ 9,724 31,965 8,318 5,605 (3,608) (1,204) 50,800 During Six Months 2023 and Six Months 2022, we had no write-offs or recoveries of our AFS fixed income securities. For information on our methodology and significant inputs used to measure expected credit losses, our accounting policy for recognizing write-offs of uncollectible amounts, and our treatment of accrued interest, refer to Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2022 Annual Report. Accrued interest on AFS securities was $58.1 million as of June 30, 2023, and $56.4 million as of December 31, 2022. We did not record any (i) write-offs of accrued interest during Six Months 2023, or (ii) material write-offs of accrued interest in Six Months 2022. (b) Quantitative information about unrealized losses on our AFS portfolio follows: June 30, 2023 Less than 12 months 12 months or longer Total ($ in thousands) Fair Value Unrealized Fair Value Unrealized Fair Value Unrealized AFS fixed income securities: U.S. government and government agencies $ 208,153 (2,831) 84,869 (18,112) 293,022 (20,943) Foreign government 4,380 (247) 5,439 (1,071) 9,819 (1,318) Obligations of states and political subdivisions 337,606 (5,554) 229,922 (31,990) 567,528 (37,544) Corporate securities 1,101,756 (40,711) 895,497 (148,953) 1,997,253 (189,664) CLO and other ABS 523,727 (17,268) 924,490 (88,689) 1,448,217 (105,957) RMBS 792,885 (26,269) 538,073 (75,540) 1,330,958 (101,809) CMBS 291,078 (12,882) 344,647 (42,162) 635,725 (55,044) Total AFS fixed income securities $ 3,259,585 (105,762) 3,022,937 (406,517) 6,282,522 (512,279) December 31, 2022 Less than 12 months 12 months or longer Total ($ in thousands) Fair Unrealized Fair Value Unrealized Fair Value Unrealized AFS fixed income securities: U.S. government and government agencies $ 166,975 (13,658) 16,011 (6,668) 182,986 (20,326) Foreign government 5,573 (608) 2,456 (699) 8,029 (1,307) Obligations of states and political subdivisions 681,795 (43,767) 16,618 (4,234) 698,413 (48,001) Corporate securities 1,889,492 (164,197) 133,223 (32,612) 2,022,715 (196,809) CLO and other ABS 916,423 (69,155) 411,283 (52,565) 1,327,706 (121,720) RMBS 887,229 (76,432) 108,041 (22,833) 995,270 (99,265) CMBS 512,953 (37,815) 77,181 (11,945) 590,134 (49,760) Total AFS fixed income securities $ 5,060,440 (405,632) 764,813 (131,556) 5,825,253 (537,188) We currently do not intend to sell any of the securities summarized in the tables above, nor do we believe we will be required to sell any of them. The decrease in gross unrealized losses as of June 30, 2023, compared to December 31, 2022, was primarily driven by a tightening of credit spreads, partially offset by an increase in benchmark U.S. Treasury rates. Considering these factors and our review of these securities under our credit loss policy as described in Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2022 Annual Report, we have concluded that no additional allowance for credit loss is required on these balances beyond the allowance for credit loss recorded as of June 30, 2023. This conclusion reflects our current judgment about the financial position and future prospects of the entities that issued the investment security and underlying collateral. (c) AFS and held-to-maturity ("HTM") fixed income securities at June 30, 2023, by contractual maturity are shown below. The maturities of RMBS, CMBS, CLO and other ABS securities were calculated using each security's estimated average life. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. AFS HTM ($ in thousands) Fair Value Carrying Value Fair Value Due in one year or less $ 369,240 443 442 Due after one year through five years 3,056,529 13,942 13,233 Due after five years through 10 years 2,912,169 9,291 8,681 Due after 10 years 694,410 — — Total fixed income securities $ 7,032,348 23,676 22,356 (d) The following table summarizes our alternative investment portfolio by strategy: June 30, 2023 December 31, 2022 ($ in thousands) Carrying Value Remaining Commitment Maximum Exposure to Loss Carrying Value Remaining Commitment Maximum Exposure to Loss Alternative Investments Private equity $ 298,219 124,213 422,432 280,980 134,676 415,656 Private credit 52,379 138,691 191,070 54,866 89,481 144,347 Real assets 38,575 19,553 58,128 35,470 21,945 57,415 Total alternative investments $ 389,173 282,457 671,630 371,316 246,102 617,418 We are contractually committed to make additional investments up to the remaining commitments stated above. We did not provide any non-contractual financial support during 2023 or 2022. The following table shows gross summarized financial information for our alternative investments portfolio, including the portion we do not own. As the majority of these investments report results to us on a one quarter lag, the summarized financial statement information is for the 3- and 6-month periods ended March 31: Income Statement Information Quarter ended June 30, Six Months ended June 30, ($ in millions) 2023 2022 2023 2022 Net investment income (loss) $ (70.6) 270.9 $ (141.3) 406.5 Realized gains 922.0 6,233.5 2,644.3 8,981.5 Net change in unrealized appreciation (depreciation) 3,754.0 (3,962.4) 5,197.8 1,215.9 Net income $ 4,605.4 2,542.0 $ 7,700.8 10,603.9 Alternative investment income included in "Net investment income earned" on our Consolidated Statements of Income $ 11.4 9.3 $ 19.2 28.4 (e) We have pledged certain AFS fixed income securities as collateral related to our borrowing relationships with the Federal Home Loan Bank of Indianapolis ("FHLBI") and the Federal Home Loan Bank of New York ("FHLBNY"). In addition, we had certain securities on deposit with various state and regulatory agencies at June 30, 2023 to comply with insurance laws. We retain all rights regarding all securities pledged as collateral. The following table summarizes the market value of these securities at June 30, 2023: ($ in millions) FHLBI Collateral FHLBNY Collateral State and Total U.S. government and government agencies $ — — 19.4 19.4 Obligations of states and political subdivisions — — 3.5 3.5 RMBS 62.1 26.9 — 89.0 CMBS 2.9 8.7 — 11.6 Total pledged as collateral $ 65.0 35.6 22.9 123.5 (f) We did not have exposure to any credit concentration risk of a single issuer greater than 10% of our stockholders' equity, other than to certain U.S. government agencies, as of June 30, 2023, or December 31, 2022. (g) The components of pre-tax net investment income earned were as follows: Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Fixed income securities $ 83,916 62,144 $ 164,003 116,069 Commercial mortgage loans ("CMLs") 2,199 1,192 4,164 2,162 Equity securities 2,236 2,639 3,441 5,057 Short-term investments 2,892 407 7,542 508 Alternative investments 11,396 9,274 19,164 28,402 Other investments 188 (214) 231 (37) Investment expenses (5,131) (5,220) (9,343) (9,337) Net investment income earned $ 97,696 70,222 $ 189,202 142,824 (h) The following table summarizes net realized and unrealized investment gains and losses for the periods indicated: Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Gross gains on sales $ 1,156 14,552 $ 4,940 16,749 Gross losses on sales (11,952) (19,345) (24,882) (32,905) Net realized gains (losses) on disposals (10,796) (4,793) (19,942) (16,156) Net unrealized gains (losses) on equity securities 4,925 (21,860) 8,173 (24,014) Net credit loss benefit (expense) on fixed income securities, AFS 864 (15,519) 10,393 (37,571) Net credit loss benefit (expense) on fixed income securities, HTM — (6) — 8 Net credit loss (expense) on CMLs (78) — (61) — Losses on securities for which we have the intent to sell (341) (702) (645) (5,499) Net realized and unrealized investment gains (losses) $ (5,426) (42,880) $ (2,082) (83,232) Net realized and unrealized investment losses decreased $37.5 million in Second Quarter 2023 and $81.2 million in Six Months 2023 compared to the same prior-year periods, primarily due to (i) a credit loss benefit recorded on our AFS fixed income securities portfolio in both current-year periods compared to credit loss expense recorded in both prior-year periods, and (ii) an increase in valuations reflecting the current public equities market. The credit loss benefit in both current-year periods reflected the tightening of credit spreads, partially offset by rising benchmark U.S. Treasury rates. Net unrealized gains and losses recognized in income on equity securities, as reflected in the table above, included the following: Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Unrealized gains (losses) recognized in income on equity securities: On securities remaining in our portfolio at end of period $ 2,784 (13,031) $ 2,685 (14,843) On securities sold in period 2,141 (8,829) 5,488 (9,171) Total unrealized gains (losses) recognized in income on equity securities $ 4,925 (21,860) $ 8,173 (24,014)

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The financial assets in our investment portfolio are primarily measured at fair value as disclosed on the Consolidated Balance Sheets. The following table presents the carrying amounts and fair values of our financial liabilities as of June 30, 2023, and December 31, 2022: June 30, 2023 December 31, 2022 ($ in thousands) Carrying Amount Fair Value Carrying Amount Fair Value Financial Liabilities Long-term debt: 7.25% Senior Notes $ 49,924 52,312 49,921 51,705 6.70% Senior Notes 99,553 102,386 99,542 99,264 5.375% Senior Notes 294,472 275,149 294,424 258,459 3.03% borrowings from FHLBI 60,000 57,011 60,000 57,175 Subtotal long-term debt 503,949 486,858 503,887 466,603 Unamortized debt issuance costs (2,814) (2,929) Finance lease obligations 2,487 3,718 Total long-term debt $ 503,622 504,676 For discussion regarding the fair value techniques of our financial instruments, refer to Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2022 Annual Report. The following tables provide quantitative disclosures of our financial assets that were measured and recorded at fair value at June 30, 2023, and December 31, 2022: June 30, 2023 Fair Value Measurements Using ($ in thousands) Assets Quoted Prices in Significant Other Significant Unobservable Description Measured on a recurring basis: AFS fixed income securities: U.S. government and government agencies $ 293,022 145,044 147,978 — Foreign government 9,819 — 9,819 — Obligations of states and political subdivisions 658,028 — 651,312 6,716 Corporate securities 2,384,970 — 2,139,481 245,489 CLO and other ABS 1,634,269 — 1,432,343 201,926 RMBS 1,407,835 — 1,407,835 — CMBS 644,405 — 644,028 377 Total AFS fixed income securities 7,032,348 145,044 6,432,796 454,508 Equity securities: Common stock 1 119,867 21,304 — 662 Preferred stock 1,773 1,773 — — Total equity securities 121,640 23,077 — 662 Short-term investments 319,456 315,574 3,882 — Total assets measured at fair value $ 7,473,444 483,695 6,436,678 455,170 December 31, 2022 Fair Value Measurements Using ($ in thousands) Assets Quoted Prices in Significant Significant Unobservable Description Measured on a recurring basis: AFS fixed income securities: U.S. government and government agencies $ 189,239 109,240 79,999 — Foreign government 9,608 — 9,608 — Obligations of states and political subdivisions 918,018 — 911,357 6,661 Corporate securities 2,335,025 — 2,147,045 187,980 CLO and other ABS 1,485,973 — 1,332,631 153,342 RMBS 1,059,832 — 1,059,832 — CMBS 614,412 — 614,037 375 Total AFS fixed income securities 6,612,107 109,240 6,154,509 348,358 Equity securities: Common stock 1 160,355 55,846 — 897 Preferred stock 1,645 1,645 — — Total equity securities 162,000 57,491 — 897 Short-term investments 440,456 418,199 22,257 — Total assets measured at fair value $ 7,214,563 584,930 6,176,766 349,255 1 Investments amounting to $97.9 million at June 30, 2023, and $103.6 million at December 31, 2022, were measured at fair value using the net asset value per share (or its practical expedient) and have not been classified in the fair value hierarchy. These investments are not redeemable and the timing of liquidations of the underlying assets is unknown at each reporting period. The fair value amounts in this table are intended to permit reconciliation of the fair value hierarchy to total assets measured at fair value. The following tables provide a summary of Level 3 changes in Six Months 2023 and Six Months 2022: June 30, 2023 ($ in thousands) Obligations of States and Political Subdivisions Corporate Securities CLO and Other ABS CMBS Common Stock Total Fair value, December 31, 2022 $ 6,661 187,980 153,342 375 897 349,255 Total net gains (losses) for the period included in: Other comprehensive income (loss) ("OCI") (7) 1,857 (1,168) 64 — 746 Net realized and unrealized gains (losses) 62 251 17 — (235) 95 Net investment income earned — 112 (20) (263) — (171) Purchases — 58,586 39,713 — — 98,299 Sales — — — — — — Issuances — — — — — — Settlements — (5,535) (3,153) (21) — (8,709) Transfers into Level 3 — 2,238 14,148 2,848 — 19,234 Transfers out of Level 3 — — (953) (2,626) — (3,579) Fair value, June 30, 2023 $ 6,716 245,489 201,926 377 662 455,170 Change in unrealized gains (losses) for the period included in earnings for assets held at period end 62 251 17 — (235) 95 Change in unrealized gains (losses) for the period included in OCI for assets held at period end (7) 1,846 (1,168) 64 — 735 June 30, 2022 ($ in thousands) Obligation of state and Political Subdivisions Corporate Securities CLO and Other ABS RMBS CMBS Total Fair value, December 31, 2021 $ 7,745 114,127 124,909 245 4,256 251,282 Total net gains (losses) for the period included in: OCI (581) (16,422) (8,592) (17) (446) (26,058) Net realized and unrealized gains (losses) (156) (2,047) (777) — (7) (2,987) Net investment income earned — 14 68 — 47 129 Purchases — 55,343 39,133 — — 94,476 Sales — — — — — — Issuances — — — — — — Settlements — (3,903) (6,479) (11) (12) (10,405) Transfers into Level 3 — 19,214 — — — 19,214 Transfers out of Level 3 — (7,037) (24,646) (217) (3,431) (35,331) Fair value, June 30, 2022 $ 7,008 159,289 123,616 — 407 290,320 Change in unrealized gains (losses) for the period included in earnings for assets held at period end (156) (2,047) (777) — (7) (2,987) Change in unrealized gains (losses) for the period included in OCI for assets held at period end (581) (16,424) (8,551) (17) (446) (26,019) The following tables present quantitative information about the significant unobservable inputs used in the fair value measurements of Level 3 assets at June 30, 2023, and December 31, 2022: June 30, 2023 ($ in thousands) Assets Measured at Fair Value Valuation Techniques Unobservable Inputs Range Weighted Average Internal valuations: Corporate securities $ 116,155 Discounted Cash Flow Illiquidity Spread (4.4)% - 5.3% 2.2% CLO and other ABS 90,768 Discounted Cash Flow Illiquidity Spread 0.01% - 19.6% 2.6% Total internal valuations 206,923 Other 1 248,247 Total Level 3 securities $ 455,170 December 31, 2022 ($ in thousands) Assets Measured at Fair Value Valuation Techniques Unobservable Inputs Range Weighted Average Internal valuations: Corporate securities $ 81,867 Discounted Cash Flow Illiquidity Spread (4.4)% - 5.3% 1.3% CLO and other ABS 59,452 Discounted Cash Flow Illiquidity Spread 0.01% - 19.6% 2.5% Total internal valuations 141,319 Other 1 207,936 Total Level 3 securities $ 349,255 1 Other is comprised of broker quotes or other third-party pricing for which there is a lack of transparency into the inputs used to develop the valuations. The quantitative details of these unobservable inputs are neither provided to us, nor reasonably available to us, and therefore are not included in the tables above. For the securities in the tables above valued using a discounted cash flow analysis, we apply an illiquidity spread in our determination of fair value. An increase in this assumption would result in a lower fair value measurement. The following tables provide quantitative information about our financial assets and liabilities that were not measured at fair value, but were disclosed as such at June 30, 2023, and December 31, 2022: June 30, 2023 Fair Value Measurements Using ($ in thousands) Assets/ Quoted Prices in Significant Other Significant Financial Assets HTM: Corporate securities $ 22,356 — 22,356 — Total HTM fixed income securities 22,356 — 22,356 — CMLs $ 163,068 — — 163,068 Financial Liabilities Long-term debt: 7.25% Senior Notes $ 52,312 — 52,312 — 6.70% Senior Notes 102,386 — 102,386 — 5.375% Senior Notes 275,149 — 275,149 — 3.03% borrowings from FHLBI 57,011 — 57,011 — Total long-term debt $ 486,858 — 486,858 — December 31, 2022 Fair Value Measurements Using ($ in thousands) Assets/ Quoted Prices in Significant Other Significant Financial Assets HTM: Obligations of states and political subdivisions $ 3,405 — 3,405 — Corporate securities 26,432 — 26,432 — Total HTM fixed income securities $ 29,837 — 29,837 — CMLs $ 139,243 — — 139,243 Financial Liabilities Long-term debt: 7.25% Senior Notes $ 51,705 — 51,705 — 6.70% Senior Notes 99,264 — 99,264 — 5.375% Senior Notes 258,459 — 258,459 — 3.03% borrowings from FHLBI 57,175 — 57,175 — Total long-term debt $ 466,603 — 466,603 —

Allowance for Credit Losses on

Allowance for Credit Losses on Premiums Receivable (Notes)	6 Months Ended
	Jun. 30, 2023
Premiums Receivable Disclosure [Abstract]
Premiums Receivable Note [Text Block]	Premiums Receivable The following table provides a roll forward of the allowance for credit losses on our premiums receivable balance for the indicated periods: Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Balance at beginning of period $ 17,100 $ 14,300 $ 16,100 $ 13,600 Current period change for expected credit losses 1,515 1,169 3,425 2,085 Write-offs charged against the allowance for credit losses (1,047) (918) (2,211) (1,438) Recoveries 332 349 586 653 Allowance for credit losses, end of period $ 17,900 $ 14,900 $ 17,900 $ 14,900 For a discussion of the methodology used to evaluate our estimate of expected credit losses on premiums receivable, refer to Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2022 Annual Report.

Reinsurance

Reinsurance	6 Months Ended
	Jun. 30, 2023
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance We evaluate and monitor the financial condition of our reinsurers under voluntary reinsurance arrangements to minimize our exposure to significant losses from reinsurer insolvencies. The following tables provide (i) a disaggregation of our reinsurance recoverable balance by financial strength rating, and (ii) an aging analysis of our past due reinsurance recoverable balances as of June 30, 2023, and December 31, 2022: June 30, 2023 ($ in thousands) Current Past Due Total Reinsurance Recoverables Financial strength rating of rated reinsurers A++ $ 80,117 $ 888 $ 81,005 A+ 347,802 5,367 353,169 A 117,592 5,316 122,908 A- 3,599 89 3,688 Total rated reinsurers $ 549,110 $ 11,660 $ 560,770 Non-rated reinsurers Federal and state pools $ 80,629 $ — $ 80,629 Other than federal and state pools 6,717 475 7,192 Total non-rated reinsurers $ 87,346 $ 475 $ 87,821 Total reinsurance recoverable, gross $ 636,456 $ 12,135 $ 648,591 Less: allowance for credit losses (1,800) Total reinsurance recoverable, net $ 646,791 December 31, 2022 ($ in thousands) Current Past Due Total Reinsurance Recoverables Financial strength rating of rated reinsurers A++ $ 46,282 $ 1 $ 46,283 A+ 425,395 3,191 428,586 A 106,102 1,315 107,417 A- 7,148 89 7,237 Total rated reinsurers $ 584,927 $ 4,596 $ 589,523 Non-rated reinsurers Federal and state pools $ 180,794 $ — $ 180,794 Other than federal and state pools 13,678 415 14,093 Total non-rated reinsurers $ 194,472 $ 415 $ 194,887 Total reinsurance recoverable, gross $ 779,399 $ 5,011 $ 784,410 Less: allowance for credit losses (1,600) Total reinsurance recoverable, net $ 782,810 The $100.2 million decrease in "Federal and state pools" as of June 30, 2023, compared to December 31, 2022, was primarily due to a decrease in the NFIP reserves recorded as of December 31, 2022, for flood losses in Florida and surrounding states as a result of Hurricane Ian, which are 100% ceded to the NFIP. The following table provides a roll forward of the allowance for credit losses on our reinsurance recoverable balance for the periods indicated: ($ in thousands) Quarter ended June 30, Six Months ended June 30, 2023 2022 2023 2022 Balance at beginning of period $ 2,300 1,600 $ 1,600 1,600 Current period change for expected credit losses (500) — 200 — Write-offs charged against the allowance for credit losses — — — — Recoveries — — — — Allowance for credit losses, end of period $ 1,800 1,600 $ 1,800 1,600 For a discussion of the methodology used to evaluate our estimate of expected credit losses on our reinsurance recoverable balance, refer to Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2022 Annual Report. The following table lists direct, assumed, and ceded reinsurance amounts for premiums written, premiums earned, and loss and loss expense incurred for the indicated periods. For more information about reinsurance, refer to Note 9. “Reinsurance” in Item 8. “Financial Statements and Supplementary Data.” of our 2022 Annual Report. Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Premiums written: Direct $ 1,232,496 1,050,506 $ 2,365,256 2,051,555 Assumed 5,577 8,552 10,971 13,866 Ceded (153,166) (128,317) (291,552) (244,882) Net $ 1,084,907 930,741 $ 2,084,675 1,820,539 Premiums earned: Direct $ 1,073,498 955,651 $ 2,105,726 1,887,027 Assumed 5,968 7,481 12,258 13,009 Ceded (137,316) (128,693) (273,498) (253,314) Net $ 942,150 834,439 $ 1,844,486 1,646,722 Loss and loss expenses incurred: Direct $ 698,994 559,913 $ 1,312,223 1,088,501 Assumed 5,678 5,125 10,933 9,403 Ceded (58,542) (40,170) (109,588) (78,800) Net $ 646,130 524,868 $ 1,213,568 1,019,104

Reserve for Loss and Loss Expen

Reserve for Loss and Loss Expense	6 Months Ended
	Jun. 30, 2023
Insurance Loss Reserves [Abstract]
Reserve for Loss and Loss Expense	Reserve for Loss and Loss Expense The table below provides a roll forward of the reserve for loss and loss expense for beginning and ending reserve balances: Six Months ended June 30, ($ in thousands) 2023 2022 Gross reserve for loss and loss expense, at beginning of period $ 5,144,821 4,580,903 Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of period 757,513 578,641 Net reserve for loss and loss expense, at beginning of period 4,387,308 4,002,262 Incurred loss and loss expense for claims occurring in the: Current year 1,221,635 1,041,778 Prior years (8,067) (22,674) Total incurred loss and loss expense 1,213,568 1,019,104 Paid loss and loss expense for claims occurring in the: Current year 320,026 272,401 Prior years 720,314 570,868 Total paid loss and loss expense 1,040,340 843,269 Net reserve for loss and loss expense, at end of period 4,560,536 4,178,097 Add: Reinsurance recoverable on unpaid loss and loss expense, at end of period 616,487 544,082 Gross reserve for loss and loss expense, at end of period $ 5,177,023 4,722,179 Prior year reserve development in Six Months 2023 was favorable by $8.1 million, consisting of $16.5 million of favorable casualty reserve development, partially offset by $8.4 million of unfavorable property reserve development. The favorable casualty reserve development included $17.5 million in our workers compensation line of business and $5.0 million in our Excess and Surplus ("E&S") casualty lines of business, partially offset by $6.0 million of unfavorable casualty reserve development in our personal automobile line of business. Prior year reserve development in Six Months 2022 was favorable by $22.7 million, consisting of $32.0 million of favorable casualty reserve development, partially offset by $9.3 million of unfavorable property reserve development. The favorable casualty reserve development included $20.0 million in our workers compensation line of business, $7.0 million in our bonds line of business, and $5.0 million in our general liability line of business.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2023
Segment Reporting [Abstract]
Segment Information	Segment Information We evaluate the results of our four reportable segments as follows: • Our Standard Commercial Lines, Standard Personal Lines, and E&S Lines are evaluated on (i) before and after-tax underwriting results (net premiums earned, incurred loss and loss expense, policyholder dividends, policy acquisition costs, and other underwriting expenses), (ii) their return on equity ("ROE") contribution, and (iii) their combined ratios. • Our Investments segment is primarily evaluated on after-tax net investment income and its ROE contribution. After-tax net realized and unrealized gains and losses are also included in our Investments segment results. In computing each segment's results, we do not make adjustments for interest expense or corporate expenses. No segment has a separate investment portfolio or allocated assets. The following summaries present revenues (net investment income and net realized and unrealized gains and losses on investments in the case of the Investments segment) and pre-tax income for the individual segments: Revenue by Segment Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Standard Commercial Lines: Net premiums earned: General liability $ 254,510 226,285 $ 497,859 442,610 Commercial automobile 225,067 198,381 442,438 392,211 Commercial property 141,348 123,562 276,640 243,624 Workers compensation 88,746 83,502 172,930 168,182 Businessowners' policies 34,385 31,508 67,556 61,552 Bonds 11,619 10,682 23,016 21,042 Other 7,034 6,317 13,885 12,485 Miscellaneous income 5,568 2,596 7,749 3,697 Total Standard Commercial Lines revenue 768,277 682,833 1,502,073 1,345,403 Standard Personal Lines: Net premiums earned: Personal automobile 48,230 39,952 93,144 79,668 Homeowners 36,902 31,630 71,915 62,817 Other 2,038 1,756 3,981 3,495 Miscellaneous income 536 441 989 869 Total Standard Personal Lines revenue 87,706 73,779 170,029 146,849 E&S Lines: Net premiums earned: Casualty lines 62,151 56,041 122,968 110,665 Property lines 30,120 24,823 58,154 48,371 Total E&S Lines revenue 92,271 80,864 181,122 159,036 Investments: Net investment income earned 97,696 70,222 189,202 142,824 Net realized and unrealized investment gains (losses) (5,426) (42,880) (2,082) (83,232) Total Investments revenue 92,270 27,342 187,120 59,592 Total revenues $ 1,040,524 864,818 $ 2,040,344 1,710,880 Income Before and After Federal Income Tax Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Standard Commercial Lines: Underwriting income (loss), before federal income tax $ 22,146 46,708 $ 61,067 89,092 Underwriting income (loss), after federal income tax 17,495 36,899 48,243 70,383 Combined ratio 97.1 % 93.1 95.9 93.4 ROE contribution 2.8 6.0 4.1 5.5 Standard Personal Lines: Underwriting income (loss), before federal income tax $ (23,060) (12,367) $ (36,133) (5,847) Underwriting income (loss), after federal income tax (18,217) (9,770) (28,545) (4,619) Combined ratio 126.5 % 116.9 121.4 104.0 ROE contribution (2.9) (1.6) (2.4) (0.4) E&S Lines: Underwriting income (loss), before federal income tax $ (612) 3,372 $ 12,723 10,297 Underwriting income (loss), after federal income tax (483) 2,664 10,051 8,135 Combined ratio 100.7 % 95.8 93.0 93.5 ROE contribution (0.1) 0.4 0.8 0.6 Investments: Net investment income earned $ 97,696 70,222 $ 189,202 142,824 Net realized and unrealized investment gains (losses) (5,426) (42,880) (2,082) (83,232) Total investments segment income, before federal income tax 92,270 27,342 187,120 59,592 Tax on investments segment income 18,745 4,559 37,901 10,172 Total investments segment income, after federal income tax $ 73,525 22,783 $ 149,219 49,420 ROE contribution of after-tax net investment income earned 12.6 9.1 12.5 8.9 Reconciliation of Segment Results to Income Before Federal Income Tax Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Underwriting income Standard Commercial Lines $ 22,146 46,708 $ 61,067 89,092 Standard Personal Lines (23,060) (12,367) (36,133) (5,847) E&S Lines (612) 3,372 12,723 10,297 Investment income 92,270 27,342 187,120 59,592 Total all segments 90,744 65,055 224,777 153,134 Interest expense (7,258) (7,252) (14,424) (14,420) Corporate expenses (9,329) (7,899) (21,437) (18,920) Income, before federal income tax $ 74,157 49,904 $ 188,916 119,794 Preferred stock dividends (2,300) (2,300) (4,600) (4,600) Income available to common stockholders, before federal income tax $ 71,857 47,604 $ 184,316 115,194

Retirement Plans

Retirement Plans	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Retirement Plans	Retirement Plans The primary pension plan for our employees is the Retirement Income Plan for Selective Insurance Company of America (the “Pension Plan”). The plan is closed to new entrants, and benefits ceased accruing under the Pension Plan after March 31, 2016. For more information about Selective Insurance Company of America's ("SICA") retirement plans, see Note 15. “Retirement Plans” in Item 8. “Financial Statements and Supplementary Data.” of our 2022 Annual Report. The following tables provide information about the Pension Plan: Pension Plan Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Net Periodic Pension Cost (Benefit): Interest cost $ 3,866 2,486 $ 7,732 4,972 Expected return on plan assets (5,772) (5,537) (11,545) (11,074) Amortization of unrecognized net actuarial loss 750 367 1,501 733 Total net periodic pension cost (benefit) 1 $ (1,156) (2,684) $ (2,312) (5,369) 1 The components of net periodic pension cost (benefit) are included within "Loss and loss expense incurred" and "Other insurance expenses" on the Consolidated Statements of Income. Pension Plan Six Months ended June 30, 2023 2022 Weighted-Average Expense Assumptions: Discount rate 5.21 % 2.98 % Effective interest rate for calculation of interest cost 5.09 2.48 Expected return on plan assets 6.90 5.00

Comprehensive Income

Comprehensive Income	6 Months Ended
	Jun. 30, 2023
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Comprehensive Income	Comprehensive Income The components of comprehensive income, both gross and net of tax, for Second Quarter 2023 and Six Months 2023 and Second Quarter 2022 and Six Months 2022 were as follows: Second Quarter 2023 ($ in thousands) Gross Tax Net Net income $ 74,157 15,549 58,608 Components of OCI: Unrealized gains (losses) on investment securities : Unrealized holding gains (losses) during the period (60,681) (12,744) (47,937) Unrealized gains (losses) on securities with credit loss recognized in earnings (6,030) (1,266) (4,764) Amounts reclassified into net income: Net realized (gains) losses on disposals and intent-to-sell AFS securities 9,383 1,970 7,413 Credit loss (benefit) expense (864) (181) (683) Total unrealized gains (losses) on investment securities (58,192) (12,221) (45,971) Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 757 159 598 Total defined benefit pension and post-retirement plans 757 159 598 Other comprehensive income (loss) (57,435) (12,062) (45,373) Comprehensive income (loss) $ 16,722 3,487 13,235 Second Quarter 2022 ($ in thousands) Gross Tax Net Net income $ 49,904 10,384 39,520 Components of OCI: Unrealized gains (losses) on investment securities: Unrealized holding gains (losses) during the period (222,903) (46,810) (176,093) Unrealized gains (losses) on securities with credit loss recognized in earnings (72,691) (15,264) (57,427) Amounts reclassified into net income: Net realized (gains) losses on disposals and intent-to-sell AFS securities 18,170 3,816 14,354 Credit loss (benefit) expense 15,519 3,258 12,261 Total unrealized gains (losses) on investment securities (261,905) (55,000) (206,905) Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 417 87 330 Total defined benefit pension and post-retirement plans 417 87 330 Other comprehensive income (loss) (261,488) (54,913) (206,575) Comprehensive income (loss) $ (211,584) (44,529) (167,055) Six Months 2023 ($ in thousands) Gross Tax Net Net income $ 188,916 37,734 151,182 Components of OCI: Unrealized gains (losses) on investment securities : Unrealized holding gains (losses) during the period 5,244 1,102 4,142 Unrealized gains (losses) on securities with credit loss recognized in earnings 16,401 3,444 12,957 Amounts reclassified into net income: Net realized (gains) losses on disposals and intent-to-sell AFS securities 15,487 3,252 12,235 Credit loss (benefit) expense (10,393) (2,183) (8,210) Total unrealized gains (losses) on investment securities 26,739 5,615 21,124 Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 1,514 318 1,196 Total defined benefit pension and post-retirement plans 1,514 318 1,196 Other comprehensive income (loss) 28,253 5,933 22,320 Comprehensive income (loss) $ 217,169 43,667 173,502 Six Months 2022 ($ in thousands) Gross Tax Net Net income $ 119,794 23,944 95,850 Components of OCI: Unrealized gains (losses) on investment securities: Unrealized holding gains (losses) during the period (484,735) (101,794) (382,941) Unrealized gains (losses) on securities with credit loss recognized in earnings (159,312) (33,455) (125,857) Amounts reclassified into net income: HTM securities 1 — 1 Net realized (gains) losses on disposals and intent-to-sell AFS securities 34,161 7,174 26,987 Credit loss (benefit) expense 37,571 7,889 29,682 Total unrealized gains (losses) on investment securities (572,314) (120,186) (452,128) Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 834 175 659 Total defined benefit pension and post-retirement plans 834 175 659 Other comprehensive income (loss) (571,480) (120,011) (451,469) Comprehensive income (loss) $ (451,686) (96,067) (355,619) The balances of, and changes in, each component of accumulated other comprehensive income ("AOCI") (net of taxes) as of June 30, 2023, were as follows: June 30, 2023 Net Unrealized Gains (Losses) on Investment Securities Defined Benefit Pension and Post-Retirement Plans Total AOCI ($ in thousands) Credit Loss Related 1 All Investments Balance, December 31, 2022 $ (121,838) (295,197) (417,035) (81,007) (498,042) OCI before reclassifications 12,957 4,142 17,099 — 17,099 Amounts reclassified from AOCI (8,210) 12,235 4,025 1,196 5,221 Net current period OCI 4,747 16,377 21,124 1,196 22,320 Balance, June 30, 2023 $ (117,091) (278,820) (395,911) (79,811) (475,722) 1 Represents change in unrealized gains (losses) on securities with credit loss recognized in earnings. The reclassifications out of AOCI were as follows: Quarter ended June 30, Six Months ended June 30, Affected Line Item in the Unaudited Consolidated Statements of Income ($ in thousands) 2023 2022 2023 2022 HTM related Unrealized (gains) losses on HTM disposals $ — — $ — — Net realized and unrealized investment gains (losses) Amortization of net unrealized losses (gains) on HTM securities — — — 1 Net investment income earned — — — 1 Income before federal income tax — — — — Total federal income tax expense — — — 1 Net income Net realized (gains) losses on disposals and intent-to-sell AFS securities Net realized (gains) losses on disposals and intent-to-sell AFS securities 9,383 18,170 15,487 34,161 Net realized and unrealized investment gains (losses) 9,383 18,170 15,487 34,161 Income before federal income tax (1,970) (3,816) (3,252) (7,174) Total federal income tax expense 7,413 14,354 12,235 26,987 Net income Credit loss related Credit loss (benefit) expense (864) 15,519 (10,393) 37,571 Net realized and unrealized investment gains (losses) (864) 15,519 (10,393) 37,571 Income before federal income tax 181 (3,258) 2,183 (7,889) Total federal income tax expense (683) 12,261 (8,210) 29,682 Net income Defined benefit pension and post-retirement life plans Net actuarial loss 173 84 348 180 Loss and loss expense incurred 584 333 1,166 654 Other insurance expenses Total defined benefit pension and post-retirement life 757 417 1,514 834 Income before federal income tax (159) (87) (318) (175) Total federal income tax expense 598 330 1,196 659 Net income Total reclassifications for the period $ 7,328 26,945 $ 5,221 57,329 Net income

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2023
Earnings Per Share [Abstract]
Earnings Per Share	Earnings per Common Share The following table presents the calculations of earnings per common share ("EPS") on a basic and diluted basis: Quarter ended June 30, Six Months ended June 30, (in thousands, except per share amounts) 2023 2022 2023 2022 Net income available to common stockholders: $ 56,308 37,220 146,582 91,250 Weighted average common shares outstanding: Weighted average common shares outstanding - basic 60,614 60,440 60,575 60,412 Effect of dilutive securities - stock compensation plans 323 407 343 416 Weighted average common shares outstanding - diluted 60,937 60,847 60,918 60,828 EPS: Basic $ 0.93 0.62 2.42 1.51 Diluted 0.92 0.61 2.41 1.50

Litigation

Litigation	6 Months Ended
	Jun. 30, 2023
Loss Contingency, Information about Litigation Matters [Abstract]
Litigation	Litigation As of June 30, 2023, we do not believe we are involved in any legal action that could have a material adverse effect on our consolidated financial condition, results of operations, or cash flows. In the ordinary course of conducting business, we are parties in various legal actions. Most are claims litigation involving our ten insurance subsidiaries (collectively referred to as "Insurance Subsidiaries") as (i) liability insurers defending or providing indemnity for third-party claims brought against our customers, (ii) insurers defending first-party coverage claims brought against them, or (iii) liability insurers seeking declaratory judgment on our insurance coverage obligations. We account for such activity by establishing unpaid loss and loss expense reserves. Considering potential losses and defense costs reserves, we expect that any potential ultimate liability for ordinary course claims litigation will not be material to our consolidated financial condition, results of operations, or cash flows. All our commercial property and businessowners' policies require direct physical loss of or damage to property by a covered cause of loss. All our standard lines commercial property and businessowners' policies also include or attach an exclusion that states all loss or property damage caused by or resulting from any virus, bacterium, or other microorganism that induces or is capable of inducing physical distress, illness, or disease is not a covered cause of loss ("Virus Exclusion"). Whether COVID-19-related contamination, the existence of the COVID-19 pandemic, and the resulting COVID-19-related government shutdown orders cause physical loss of or damage to property is the subject of much public debate and first-party coverage litigation against some insurers, including us. The Virus Exclusion is also the subject of first-party coverage litigation against some insurers, including us. To date, insurers (including us) have prevailed in the majority of these suits, with most decisions holding that COVID-19 does not cause physical loss of or damage to property and the Virus Exclusion is valid. Nonetheless, these two matters continue to be litigated in trial courts, are subject to review by state and federal appellate courts, and their ultimate outcome cannot be assured. From time to time, our Insurance Subsidiaries also are named as defendants in other legal actions, some asserting claims for substantial amounts. Plaintiffs may style these actions as class actions and seek judicial certification of a state or national class for allegations involving our business practices, such as improper medical provider reimbursement under workers compensation and personal and commercial automobile insurance policies or improper reimbursement for automobile parts. Similarly, our Insurance Subsidiaries can be named defendants in individual actions seeking extra-contractual damages, punitive damages, or penalties, often alleging bad faith in handling insurance claims. We believe that we have valid defenses to these allegations, and we account for such activity by establishing unpaid loss and loss expense reserves. Considering estimated losses and defense costs reserves, we expect that any potential ultimate liability for these other legal actions will not be material to our consolidated financial condition. As litigation outcomes are inherently unpredictable and the amounts sought in certain actions are large or indeterminate, adverse outcomes could potentially have a material adverse effect on our consolidated results of operations or cash flows in particular quarterly or annual periods.

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Jun. 30, 2023
Trading Arrangements [Abstract]
Non-Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false

Statements of Cash Flows (Table

Statements of Cash Flows (Tables)	6 Months Ended
	Jun. 30, 2023
Supplemental Cash Flow Information [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	Six Months ended June 30, ($ in thousands) 2023 2022 Cash paid (received) during the period for: Interest $ 14,164 14,240 Federal income tax 34,000 40,200 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases 4,038 4,086 Operating cash flows from financing leases 20 20 Financing cash flows from finance leases 1,231 1,202 Non-cash items: Corporate actions related to fixed income securities, available-for-sale ("AFS") 1 23,150 17,287 Conversion of AFS fixed income securities to equity securities — 1,463 Assets acquired under finance lease arrangements — 41 Assets acquired under operating lease arrangements 4,509 5,781 Non-cash purchase of property and equipment — 17 1 Examples of corporate actions include like-kind exchanges, non-cash acquisitions, and stock splits.
Schedule of Cash and Restricted Cash	($ in thousands) June 30, 2023 December 31, 2022 Cash $ 354 26 Restricted cash 20,904 25,183 Total cash and restricted cash shown in the Consolidated Statements of Cash Flows $ 21,258 25,209

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2023
Schedule of Investments [Line Items]
Schedule of Available-for-sale Securities	June 30, 2023 Cost/ Allowance for Credit Losses Unrealized Unrealized Fair ($ in thousands) AFS fixed income securities: U.S. government and government agencies $ 313,965 — — (20,943) 293,022 Foreign government 11,171 (34) — (1,318) 9,819 Obligations of states and political subdivisions 694,734 (769) 1,607 (37,544) 658,028 Corporate securities 2,585,819 (16,149) 4,964 (189,664) 2,384,970 Collateralized loan obligations ("CLO") and other asset-backed securities ("ABS") 1,739,788 (2,915) 3,353 (105,957) 1,634,269 Residential mortgage-backed securities ("RMBS") 1,520,170 (11,550) 1,024 (101,809) 1,407,835 Commercial mortgage-backed securities ("CMBS") 699,295 (8) 162 (55,044) 644,405 Total AFS fixed income securities $ 7,564,942 (31,425) 11,110 (512,279) 7,032,348 December 31, 2022 Cost/ Allowance for Credit Losses Unrealized Unrealized Fair ($ in thousands) AFS fixed income securities: U.S. government and government agencies $ 209,528 — 37 (20,326) 189,239 Foreign government 11,199 (284) — (1,307) 9,608 Obligations of states and political subdivisions 965,231 (1,024) 1,812 (48,001) 918,018 Corporate securities 2,558,655 (30,330) 3,509 (196,809) 2,335,025 CLO and other ABS 1,607,660 (2,375) 2,408 (121,720) 1,485,973 RMBS 1,169,546 (11,597) 1,148 (99,265) 1,059,832 CMBS 663,935 (111) 348 (49,760) 614,412 Total AFS fixed income securities $ 7,185,754 (45,721) 9,262 (537,188) 6,612,107
Debt Securities, Available-for-sale, Allowance for Credit Loss	Quarter ended June 30, 2023 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 36 — — (2) — — 34 Obligations of states and political subdivisions 737 67 — (35) — — 769 Corporate securities 16,756 1,438 — (1,070) (939) (36) 16,149 CLO and other ABS 3,895 622 — (1,595) (7) — 2,915 RMBS 11,740 1 — (50) (141) — 11,550 CMBS 390 — — (240) (142) — 8 Total AFS fixed income securities $ 33,554 2,128 — (2,992) (1,229) (36) 31,425 Quarter ended June 30, 2022 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 150 117 — 12 (14) — 265 Obligations of states and political subdivisions 1,991 534 — (1,166) (153) — 1,206 Corporate securities 23,066 8,323 — 5,732 (1,944) (105) 35,072 CLO and other ABS 2,283 530 — 819 (9) — 3,623 RMBS 10,029 173 — 507 (93) — 10,616 CMBS 80 — — (62) — — 18 Total AFS fixed income securities $ 37,599 9,677 — 5,842 (2,213) (105) 50,800 Six Months ended June 30, 2023 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 284 — — (250) — — 34 Obligations of states and political subdivisions 1,024 67 — (239) (83) — 769 Corporate securities 30,330 4,141 — (14,884) (3,387) (51) 16,149 CLO and other ABS 2,375 677 — (127) (10) — 2,915 RMBS 11,597 8 — 174 (229) — 11,550 CMBS 111 1 — 39 (143) — 8 Total AFS fixed income securities $ 45,721 4,894 — (15,287) (3,852) (51) 31,425 Six Months ended June 30, 2022 Beginning Balance Current Provision for Securities without Prior Allowance Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration Increase (Decrease) on Securities with Prior Allowance, excluding intent (or Requirement) to Sell Securities Reductions for Securities Sold Reductions for Securities Identified as Intent (or Requirement) to Sell during the Period Ending Balance ($ in thousands) Foreign government $ 46 236 — (3) (14) — 265 Obligations of states and political subdivisions 137 1,237 — (4) (164) — 1,206 Corporate securities 6,682 28,243 — 4,542 (3,191) (1,204) 35,072 CLO and other ABS 939 2,058 — 637 (11) — 3,623 RMBS 1,909 174 8,318 443 (228) — 10,616 CMBS 11 17 — (10) — — 18 Total AFS fixed income securities $ 9,724 31,965 8,318 5,605 (3,608) (1,204) 50,800
Schedule of Fair Value and Gross Pre-Tax Net Unrealized Loss of Securities by Length of Time, AFS	June 30, 2023 Less than 12 months 12 months or longer Total ($ in thousands) Fair Value Unrealized Fair Value Unrealized Fair Value Unrealized AFS fixed income securities: U.S. government and government agencies $ 208,153 (2,831) 84,869 (18,112) 293,022 (20,943) Foreign government 4,380 (247) 5,439 (1,071) 9,819 (1,318) Obligations of states and political subdivisions 337,606 (5,554) 229,922 (31,990) 567,528 (37,544) Corporate securities 1,101,756 (40,711) 895,497 (148,953) 1,997,253 (189,664) CLO and other ABS 523,727 (17,268) 924,490 (88,689) 1,448,217 (105,957) RMBS 792,885 (26,269) 538,073 (75,540) 1,330,958 (101,809) CMBS 291,078 (12,882) 344,647 (42,162) 635,725 (55,044) Total AFS fixed income securities $ 3,259,585 (105,762) 3,022,937 (406,517) 6,282,522 (512,279) December 31, 2022 Less than 12 months 12 months or longer Total ($ in thousands) Fair Unrealized Fair Value Unrealized Fair Value Unrealized AFS fixed income securities: U.S. government and government agencies $ 166,975 (13,658) 16,011 (6,668) 182,986 (20,326) Foreign government 5,573 (608) 2,456 (699) 8,029 (1,307) Obligations of states and political subdivisions 681,795 (43,767) 16,618 (4,234) 698,413 (48,001) Corporate securities 1,889,492 (164,197) 133,223 (32,612) 2,022,715 (196,809) CLO and other ABS 916,423 (69,155) 411,283 (52,565) 1,327,706 (121,720) RMBS 887,229 (76,432) 108,041 (22,833) 995,270 (99,265) CMBS 512,953 (37,815) 77,181 (11,945) 590,134 (49,760) Total AFS fixed income securities $ 5,060,440 (405,632) 764,813 (131,556) 5,825,253 (537,188)
Schedule of Fixed Maturity Securities By Contractual Maturities	AFS HTM ($ in thousands) Fair Value Carrying Value Fair Value Due in one year or less $ 369,240 443 442 Due after one year through five years 3,056,529 13,942 13,233 Due after five years through 10 years 2,912,169 9,291 8,681 Due after 10 years 694,410 — — Total fixed income securities $ 7,032,348 23,676 22,356
Schedule of Other Investment Portfolio By Strategy And Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy	June 30, 2023 December 31, 2022 ($ in thousands) Carrying Value Remaining Commitment Maximum Exposure to Loss Carrying Value Remaining Commitment Maximum Exposure to Loss Alternative Investments Private equity $ 298,219 124,213 422,432 280,980 134,676 415,656 Private credit 52,379 138,691 191,070 54,866 89,481 144,347 Real assets 38,575 19,553 58,128 35,470 21,945 57,415 Total alternative investments $ 389,173 282,457 671,630 371,316 246,102 617,418
Schedule of Aggregated Summarized Income Statement Financial Information For Partnerships In Our Alternative Investment Portfolio	Income Statement Information Quarter ended June 30, Six Months ended June 30, ($ in millions) 2023 2022 2023 2022 Net investment income (loss) $ (70.6) 270.9 $ (141.3) 406.5 Realized gains 922.0 6,233.5 2,644.3 8,981.5 Net change in unrealized appreciation (depreciation) 3,754.0 (3,962.4) 5,197.8 1,215.9 Net income $ 4,605.4 2,542.0 $ 7,700.8 10,603.9 Alternative investment income included in "Net investment income earned" on our Consolidated Statements of Income $ 11.4 9.3 $ 19.2 28.4
Schedule of Securities Pledged As Collateral	($ in millions) FHLBI Collateral FHLBNY Collateral State and Total U.S. government and government agencies $ — — 19.4 19.4 Obligations of states and political subdivisions — — 3.5 3.5 RMBS 62.1 26.9 — 89.0 CMBS 2.9 8.7 — 11.6 Total pledged as collateral $ 65.0 35.6 22.9 123.5
Schedule of Pre-Tax Net Investment Income Earned	Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Fixed income securities $ 83,916 62,144 $ 164,003 116,069 Commercial mortgage loans ("CMLs") 2,199 1,192 4,164 2,162 Equity securities 2,236 2,639 3,441 5,057 Short-term investments 2,892 407 7,542 508 Alternative investments 11,396 9,274 19,164 28,402 Other investments 188 (214) 231 (37) Investment expenses (5,131) (5,220) (9,343) (9,337) Net investment income earned $ 97,696 70,222 $ 189,202 142,824
Schedule of realized and unrealized gains (losses) on securities	Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Gross gains on sales $ 1,156 14,552 $ 4,940 16,749 Gross losses on sales (11,952) (19,345) (24,882) (32,905) Net realized gains (losses) on disposals (10,796) (4,793) (19,942) (16,156) Net unrealized gains (losses) on equity securities 4,925 (21,860) 8,173 (24,014) Net credit loss benefit (expense) on fixed income securities, AFS 864 (15,519) 10,393 (37,571) Net credit loss benefit (expense) on fixed income securities, HTM — (6) — 8 Net credit loss (expense) on CMLs (78) — (61) — Losses on securities for which we have the intent to sell (341) (702) (645) (5,499) Net realized and unrealized investment gains (losses) $ (5,426) (42,880) $ (2,082) (83,232)
Unrealized Gain (Loss) on Equity Securities	Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Unrealized gains (losses) recognized in income on equity securities: On securities remaining in our portfolio at end of period $ 2,784 (13,031) $ 2,685 (14,843) On securities sold in period 2,141 (8,829) 5,488 (9,171) Total unrealized gains (losses) recognized in income on equity securities $ 4,925 (21,860) $ 8,173 (24,014)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Carrying Values and Estimated Fair Values of Financial Liabilities	June 30, 2023 December 31, 2022 ($ in thousands) Carrying Amount Fair Value Carrying Amount Fair Value Financial Liabilities Long-term debt: 7.25% Senior Notes $ 49,924 52,312 49,921 51,705 6.70% Senior Notes 99,553 102,386 99,542 99,264 5.375% Senior Notes 294,472 275,149 294,424 258,459 3.03% borrowings from FHLBI 60,000 57,011 60,000 57,175 Subtotal long-term debt 503,949 486,858 503,887 466,603 Unamortized debt issuance costs (2,814) (2,929) Finance lease obligations 2,487 3,718 Total long-term debt $ 503,622 504,676
Schedule of Quantitative Disclosures of Our Financial Assets That Were Measured At Fair Value	June 30, 2023 Fair Value Measurements Using ($ in thousands) Assets Quoted Prices in Significant Other Significant Unobservable Description Measured on a recurring basis: AFS fixed income securities: U.S. government and government agencies $ 293,022 145,044 147,978 — Foreign government 9,819 — 9,819 — Obligations of states and political subdivisions 658,028 — 651,312 6,716 Corporate securities 2,384,970 — 2,139,481 245,489 CLO and other ABS 1,634,269 — 1,432,343 201,926 RMBS 1,407,835 — 1,407,835 — CMBS 644,405 — 644,028 377 Total AFS fixed income securities 7,032,348 145,044 6,432,796 454,508 Equity securities: Common stock 1 119,867 21,304 — 662 Preferred stock 1,773 1,773 — — Total equity securities 121,640 23,077 — 662 Short-term investments 319,456 315,574 3,882 — Total assets measured at fair value $ 7,473,444 483,695 6,436,678 455,170 December 31, 2022 Fair Value Measurements Using ($ in thousands) Assets Quoted Prices in Significant Significant Unobservable Description Measured on a recurring basis: AFS fixed income securities: U.S. government and government agencies $ 189,239 109,240 79,999 — Foreign government 9,608 — 9,608 — Obligations of states and political subdivisions 918,018 — 911,357 6,661 Corporate securities 2,335,025 — 2,147,045 187,980 CLO and other ABS 1,485,973 — 1,332,631 153,342 RMBS 1,059,832 — 1,059,832 — CMBS 614,412 — 614,037 375 Total AFS fixed income securities 6,612,107 109,240 6,154,509 348,358 Equity securities: Common stock 1 160,355 55,846 — 897 Preferred stock 1,645 1,645 — — Total equity securities 162,000 57,491 — 897 Short-term investments 440,456 418,199 22,257 — Total assets measured at fair value $ 7,214,563 584,930 6,176,766 349,255
Schedule of Summary of the Changes in Fair Value of Securities Using Level 3 Inputs	June 30, 2023 ($ in thousands) Obligations of States and Political Subdivisions Corporate Securities CLO and Other ABS CMBS Common Stock Total Fair value, December 31, 2022 $ 6,661 187,980 153,342 375 897 349,255 Total net gains (losses) for the period included in: Other comprehensive income (loss) ("OCI") (7) 1,857 (1,168) 64 — 746 Net realized and unrealized gains (losses) 62 251 17 — (235) 95 Net investment income earned — 112 (20) (263) — (171) Purchases — 58,586 39,713 — — 98,299 Sales — — — — — — Issuances — — — — — — Settlements — (5,535) (3,153) (21) — (8,709) Transfers into Level 3 — 2,238 14,148 2,848 — 19,234 Transfers out of Level 3 — — (953) (2,626) — (3,579) Fair value, June 30, 2023 $ 6,716 245,489 201,926 377 662 455,170 Change in unrealized gains (losses) for the period included in earnings for assets held at period end 62 251 17 — (235) 95 Change in unrealized gains (losses) for the period included in OCI for assets held at period end (7) 1,846 (1,168) 64 — 735 June 30, 2022 ($ in thousands) Obligation of state and Political Subdivisions Corporate Securities CLO and Other ABS RMBS CMBS Total Fair value, December 31, 2021 $ 7,745 114,127 124,909 245 4,256 251,282 Total net gains (losses) for the period included in: OCI (581) (16,422) (8,592) (17) (446) (26,058) Net realized and unrealized gains (losses) (156) (2,047) (777) — (7) (2,987) Net investment income earned — 14 68 — 47 129 Purchases — 55,343 39,133 — — 94,476 Sales — — — — — — Issuances — — — — — — Settlements — (3,903) (6,479) (11) (12) (10,405) Transfers into Level 3 — 19,214 — — — 19,214 Transfers out of Level 3 — (7,037) (24,646) (217) (3,431) (35,331) Fair value, June 30, 2022 $ 7,008 159,289 123,616 — 407 290,320 Change in unrealized gains (losses) for the period included in earnings for assets held at period end (156) (2,047) (777) — (7) (2,987) Change in unrealized gains (losses) for the period included in OCI for assets held at period end (581) (16,424) (8,551) (17) (446) (26,019)
Fair Value Measurement Inputs and Valuation Techniques	June 30, 2023 ($ in thousands) Assets Measured at Fair Value Valuation Techniques Unobservable Inputs Range Weighted Average Internal valuations: Corporate securities $ 116,155 Discounted Cash Flow Illiquidity Spread (4.4)% - 5.3% 2.2% CLO and other ABS 90,768 Discounted Cash Flow Illiquidity Spread 0.01% - 19.6% 2.6% Total internal valuations 206,923 Other 1 248,247 Total Level 3 securities $ 455,170 December 31, 2022 ($ in thousands) Assets Measured at Fair Value Valuation Techniques Unobservable Inputs Range Weighted Average Internal valuations: Corporate securities $ 81,867 Discounted Cash Flow Illiquidity Spread (4.4)% - 5.3% 1.3% CLO and other ABS 59,452 Discounted Cash Flow Illiquidity Spread 0.01% - 19.6% 2.5% Total internal valuations 141,319 Other 1 207,936 Total Level 3 securities $ 349,255 1 Other is comprised of broker quotes or other third-party pricing for which there is a lack of transparency into the inputs used to develop the valuations. The quantitative details of these unobservable inputs are neither provided to us, nor reasonably available to us, and therefore are not included in the tables above.
Schedule of Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value	June 30, 2023 Fair Value Measurements Using ($ in thousands) Assets/ Quoted Prices in Significant Other Significant Financial Assets HTM: Corporate securities $ 22,356 — 22,356 — Total HTM fixed income securities 22,356 — 22,356 — CMLs $ 163,068 — — 163,068 Financial Liabilities Long-term debt: 7.25% Senior Notes $ 52,312 — 52,312 — 6.70% Senior Notes 102,386 — 102,386 — 5.375% Senior Notes 275,149 — 275,149 — 3.03% borrowings from FHLBI 57,011 — 57,011 — Total long-term debt $ 486,858 — 486,858 — December 31, 2022 Fair Value Measurements Using ($ in thousands) Assets/ Quoted Prices in Significant Other Significant Financial Assets HTM: Obligations of states and political subdivisions $ 3,405 — 3,405 — Corporate securities 26,432 — 26,432 — Total HTM fixed income securities $ 29,837 — 29,837 — CMLs $ 139,243 — — 139,243 Financial Liabilities Long-term debt: 7.25% Senior Notes $ 51,705 — 51,705 — 6.70% Senior Notes 99,264 — 99,264 — 5.375% Senior Notes 258,459 — 258,459 — 3.03% borrowings from FHLBI 57,175 — 57,175 — Total long-term debt $ 466,603 — 466,603 —

Allowance for Credit Losses o_2

Allowance for Credit Losses on Premiums Receivable (Tables)	6 Months Ended
	Jun. 30, 2023
Premiums Receivable Disclosure [Abstract]
Allowance for Credit Losses on Premiums Receivable [Table Text Block]	Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Balance at beginning of period $ 17,100 $ 14,300 $ 16,100 $ 13,600 Current period change for expected credit losses 1,515 1,169 3,425 2,085 Write-offs charged against the allowance for credit losses (1,047) (918) (2,211) (1,438) Recoveries 332 349 586 653 Allowance for credit losses, end of period $ 17,900 $ 14,900 $ 17,900 $ 14,900

Reinsurance (Tables)

Reinsurance (Tables)	6 Months Ended
	Jun. 30, 2023
Reinsurance Disclosures [Abstract]
Reinsurance Recoverable, Credit Quality Indicator [Table Text Block]	June 30, 2023 ($ in thousands) Current Past Due Total Reinsurance Recoverables Financial strength rating of rated reinsurers A++ $ 80,117 $ 888 $ 81,005 A+ 347,802 5,367 353,169 A 117,592 5,316 122,908 A- 3,599 89 3,688 Total rated reinsurers $ 549,110 $ 11,660 $ 560,770 Non-rated reinsurers Federal and state pools $ 80,629 $ — $ 80,629 Other than federal and state pools 6,717 475 7,192 Total non-rated reinsurers $ 87,346 $ 475 $ 87,821 Total reinsurance recoverable, gross $ 636,456 $ 12,135 $ 648,591 Less: allowance for credit losses (1,800) Total reinsurance recoverable, net $ 646,791 December 31, 2022 ($ in thousands) Current Past Due Total Reinsurance Recoverables Financial strength rating of rated reinsurers A++ $ 46,282 $ 1 $ 46,283 A+ 425,395 3,191 428,586 A 106,102 1,315 107,417 A- 7,148 89 7,237 Total rated reinsurers $ 584,927 $ 4,596 $ 589,523 Non-rated reinsurers Federal and state pools $ 180,794 $ — $ 180,794 Other than federal and state pools 13,678 415 14,093 Total non-rated reinsurers $ 194,472 $ 415 $ 194,887 Total reinsurance recoverable, gross $ 779,399 $ 5,011 $ 784,410 Less: allowance for credit losses (1,600) Total reinsurance recoverable, net $ 782,810
Reinsurance Recoverable, Allowance for Credit Loss [Table Text Block]	($ in thousands) Quarter ended June 30, Six Months ended June 30, 2023 2022 2023 2022 Balance at beginning of period $ 2,300 1,600 $ 1,600 1,600 Current period change for expected credit losses (500) — 200 — Write-offs charged against the allowance for credit losses — — — — Recoveries — — — — Allowance for credit losses, end of period $ 1,800 1,600 $ 1,800 1,600
Schedule of List Of Direct, Assumed, And Ceded Reinsurance Amounts	Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Premiums written: Direct $ 1,232,496 1,050,506 $ 2,365,256 2,051,555 Assumed 5,577 8,552 10,971 13,866 Ceded (153,166) (128,317) (291,552) (244,882) Net $ 1,084,907 930,741 $ 2,084,675 1,820,539 Premiums earned: Direct $ 1,073,498 955,651 $ 2,105,726 1,887,027 Assumed 5,968 7,481 12,258 13,009 Ceded (137,316) (128,693) (273,498) (253,314) Net $ 942,150 834,439 $ 1,844,486 1,646,722 Loss and loss expenses incurred: Direct $ 698,994 559,913 $ 1,312,223 1,088,501 Assumed 5,678 5,125 10,933 9,403 Ceded (58,542) (40,170) (109,588) (78,800) Net $ 646,130 524,868 $ 1,213,568 1,019,104

Reserve for Loss and Loss Exp_2

Reserve for Loss and Loss Expense (Tables)	6 Months Ended
	Jun. 30, 2023
Insurance Loss Reserves [Abstract]
Schedule of Roll Forward of Reserve for Loss and Loss Expense	Six Months ended June 30, ($ in thousands) 2023 2022 Gross reserve for loss and loss expense, at beginning of period $ 5,144,821 4,580,903 Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of period 757,513 578,641 Net reserve for loss and loss expense, at beginning of period 4,387,308 4,002,262 Incurred loss and loss expense for claims occurring in the: Current year 1,221,635 1,041,778 Prior years (8,067) (22,674) Total incurred loss and loss expense 1,213,568 1,019,104 Paid loss and loss expense for claims occurring in the: Current year 320,026 272,401 Prior years 720,314 570,868 Total paid loss and loss expense 1,040,340 843,269 Net reserve for loss and loss expense, at end of period 4,560,536 4,178,097 Add: Reinsurance recoverable on unpaid loss and loss expense, at end of period 616,487 544,082 Gross reserve for loss and loss expense, at end of period $ 5,177,023 4,722,179

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2023
Segment Reporting [Abstract]
Schedule of Revenue By Segment	Revenue by Segment Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Standard Commercial Lines: Net premiums earned: General liability $ 254,510 226,285 $ 497,859 442,610 Commercial automobile 225,067 198,381 442,438 392,211 Commercial property 141,348 123,562 276,640 243,624 Workers compensation 88,746 83,502 172,930 168,182 Businessowners' policies 34,385 31,508 67,556 61,552 Bonds 11,619 10,682 23,016 21,042 Other 7,034 6,317 13,885 12,485 Miscellaneous income 5,568 2,596 7,749 3,697 Total Standard Commercial Lines revenue 768,277 682,833 1,502,073 1,345,403 Standard Personal Lines: Net premiums earned: Personal automobile 48,230 39,952 93,144 79,668 Homeowners 36,902 31,630 71,915 62,817 Other 2,038 1,756 3,981 3,495 Miscellaneous income 536 441 989 869 Total Standard Personal Lines revenue 87,706 73,779 170,029 146,849 E&S Lines: Net premiums earned: Casualty lines 62,151 56,041 122,968 110,665 Property lines 30,120 24,823 58,154 48,371 Total E&S Lines revenue 92,271 80,864 181,122 159,036 Investments: Net investment income earned 97,696 70,222 189,202 142,824 Net realized and unrealized investment gains (losses) (5,426) (42,880) (2,082) (83,232) Total Investments revenue 92,270 27,342 187,120 59,592 Total revenues $ 1,040,524 864,818 $ 2,040,344 1,710,880
Schedule of Income Before and After Federal Income Tax	Income Before and After Federal Income Tax Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Standard Commercial Lines: Underwriting income (loss), before federal income tax $ 22,146 46,708 $ 61,067 89,092 Underwriting income (loss), after federal income tax 17,495 36,899 48,243 70,383 Combined ratio 97.1 % 93.1 95.9 93.4 ROE contribution 2.8 6.0 4.1 5.5 Standard Personal Lines: Underwriting income (loss), before federal income tax $ (23,060) (12,367) $ (36,133) (5,847) Underwriting income (loss), after federal income tax (18,217) (9,770) (28,545) (4,619) Combined ratio 126.5 % 116.9 121.4 104.0 ROE contribution (2.9) (1.6) (2.4) (0.4) E&S Lines: Underwriting income (loss), before federal income tax $ (612) 3,372 $ 12,723 10,297 Underwriting income (loss), after federal income tax (483) 2,664 10,051 8,135 Combined ratio 100.7 % 95.8 93.0 93.5 ROE contribution (0.1) 0.4 0.8 0.6 Investments: Net investment income earned $ 97,696 70,222 $ 189,202 142,824 Net realized and unrealized investment gains (losses) (5,426) (42,880) (2,082) (83,232) Total investments segment income, before federal income tax 92,270 27,342 187,120 59,592 Tax on investments segment income 18,745 4,559 37,901 10,172 Total investments segment income, after federal income tax $ 73,525 22,783 $ 149,219 49,420 ROE contribution of after-tax net investment income earned 12.6 9.1 12.5 8.9
Schedule of Reconciliation of Segment Results to Income Before Federal Income Tax	Reconciliation of Segment Results to Income Before Federal Income Tax Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Underwriting income Standard Commercial Lines $ 22,146 46,708 $ 61,067 89,092 Standard Personal Lines (23,060) (12,367) (36,133) (5,847) E&S Lines (612) 3,372 12,723 10,297 Investment income 92,270 27,342 187,120 59,592 Total all segments 90,744 65,055 224,777 153,134 Interest expense (7,258) (7,252) (14,424) (14,420) Corporate expenses (9,329) (7,899) (21,437) (18,920) Income, before federal income tax $ 74,157 49,904 $ 188,916 119,794 Preferred stock dividends (2,300) (2,300) (4,600) (4,600) Income available to common stockholders, before federal income tax $ 71,857 47,604 $ 184,316 115,194

Retirement Plans (Table)

Retirement Plans (Table)	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Schedule of Components of Net Periodic Benefit Cost	Pension Plan Quarter ended June 30, Six Months ended June 30, ($ in thousands) 2023 2022 2023 2022 Net Periodic Pension Cost (Benefit): Interest cost $ 3,866 2,486 $ 7,732 4,972 Expected return on plan assets (5,772) (5,537) (11,545) (11,074) Amortization of unrecognized net actuarial loss 750 367 1,501 733 Total net periodic pension cost (benefit) 1 $ (1,156) (2,684) $ (2,312) (5,369) 1 The components of net periodic pension cost (benefit) are included within "Loss and loss expense incurred" and "Other insurance expenses" on the Consolidated Statements of Income.
Schedule of Weighted-Average Expense Assumptions	Pension Plan Six Months ended June 30, 2023 2022 Weighted-Average Expense Assumptions: Discount rate 5.21 % 2.98 % Effective interest rate for calculation of interest cost 5.09 2.48 Expected return on plan assets 6.90 5.00

Comprehensive Income (Tables)

Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2023
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Schedule of Components of Comprehensive Income-Gross and Net of Tax	Second Quarter 2023 ($ in thousands) Gross Tax Net Net income $ 74,157 15,549 58,608 Components of OCI: Unrealized gains (losses) on investment securities : Unrealized holding gains (losses) during the period (60,681) (12,744) (47,937) Unrealized gains (losses) on securities with credit loss recognized in earnings (6,030) (1,266) (4,764) Amounts reclassified into net income: Net realized (gains) losses on disposals and intent-to-sell AFS securities 9,383 1,970 7,413 Credit loss (benefit) expense (864) (181) (683) Total unrealized gains (losses) on investment securities (58,192) (12,221) (45,971) Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 757 159 598 Total defined benefit pension and post-retirement plans 757 159 598 Other comprehensive income (loss) (57,435) (12,062) (45,373) Comprehensive income (loss) $ 16,722 3,487 13,235 Second Quarter 2022 ($ in thousands) Gross Tax Net Net income $ 49,904 10,384 39,520 Components of OCI: Unrealized gains (losses) on investment securities: Unrealized holding gains (losses) during the period (222,903) (46,810) (176,093) Unrealized gains (losses) on securities with credit loss recognized in earnings (72,691) (15,264) (57,427) Amounts reclassified into net income: Net realized (gains) losses on disposals and intent-to-sell AFS securities 18,170 3,816 14,354 Credit loss (benefit) expense 15,519 3,258 12,261 Total unrealized gains (losses) on investment securities (261,905) (55,000) (206,905) Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 417 87 330 Total defined benefit pension and post-retirement plans 417 87 330 Other comprehensive income (loss) (261,488) (54,913) (206,575) Comprehensive income (loss) $ (211,584) (44,529) (167,055) Six Months 2023 ($ in thousands) Gross Tax Net Net income $ 188,916 37,734 151,182 Components of OCI: Unrealized gains (losses) on investment securities : Unrealized holding gains (losses) during the period 5,244 1,102 4,142 Unrealized gains (losses) on securities with credit loss recognized in earnings 16,401 3,444 12,957 Amounts reclassified into net income: Net realized (gains) losses on disposals and intent-to-sell AFS securities 15,487 3,252 12,235 Credit loss (benefit) expense (10,393) (2,183) (8,210) Total unrealized gains (losses) on investment securities 26,739 5,615 21,124 Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 1,514 318 1,196 Total defined benefit pension and post-retirement plans 1,514 318 1,196 Other comprehensive income (loss) 28,253 5,933 22,320 Comprehensive income (loss) $ 217,169 43,667 173,502 Six Months 2022 ($ in thousands) Gross Tax Net Net income $ 119,794 23,944 95,850 Components of OCI: Unrealized gains (losses) on investment securities: Unrealized holding gains (losses) during the period (484,735) (101,794) (382,941) Unrealized gains (losses) on securities with credit loss recognized in earnings (159,312) (33,455) (125,857) Amounts reclassified into net income: HTM securities 1 — 1 Net realized (gains) losses on disposals and intent-to-sell AFS securities 34,161 7,174 26,987 Credit loss (benefit) expense 37,571 7,889 29,682 Total unrealized gains (losses) on investment securities (572,314) (120,186) (452,128) Defined benefit pension and post-retirement plans: Amounts reclassified into net income: Net actuarial (gain) loss 834 175 659 Total defined benefit pension and post-retirement plans 834 175 659 Other comprehensive income (loss) (571,480) (120,011) (451,469) Comprehensive income (loss) $ (451,686) (96,067) (355,619)
Schedule of Components of Accumulated Other Comprehensive Income Net of Tax	June 30, 2023 Net Unrealized Gains (Losses) on Investment Securities Defined Benefit Pension and Post-Retirement Plans Total AOCI ($ in thousands) Credit Loss Related 1 All Investments Balance, December 31, 2022 $ (121,838) (295,197) (417,035) (81,007) (498,042) OCI before reclassifications 12,957 4,142 17,099 — 17,099 Amounts reclassified from AOCI (8,210) 12,235 4,025 1,196 5,221 Net current period OCI 4,747 16,377 21,124 1,196 22,320 Balance, June 30, 2023 $ (117,091) (278,820) (395,911) (79,811) (475,722) 1 Represents change in unrealized gains (losses) on securities with credit loss recognized in earnings.
Schedule of Reclassifications Out Of Accumulated Other Comprehensive Income	Quarter ended June 30, Six Months ended June 30, Affected Line Item in the Unaudited Consolidated Statements of Income ($ in thousands) 2023 2022 2023 2022 HTM related Unrealized (gains) losses on HTM disposals $ — — $ — — Net realized and unrealized investment gains (losses) Amortization of net unrealized losses (gains) on HTM securities — — — 1 Net investment income earned — — — 1 Income before federal income tax — — — — Total federal income tax expense — — — 1 Net income Net realized (gains) losses on disposals and intent-to-sell AFS securities Net realized (gains) losses on disposals and intent-to-sell AFS securities 9,383 18,170 15,487 34,161 Net realized and unrealized investment gains (losses) 9,383 18,170 15,487 34,161 Income before federal income tax (1,970) (3,816) (3,252) (7,174) Total federal income tax expense 7,413 14,354 12,235 26,987 Net income Credit loss related Credit loss (benefit) expense (864) 15,519 (10,393) 37,571 Net realized and unrealized investment gains (losses) (864) 15,519 (10,393) 37,571 Income before federal income tax 181 (3,258) 2,183 (7,889) Total federal income tax expense (683) 12,261 (8,210) 29,682 Net income Defined benefit pension and post-retirement life plans Net actuarial loss 173 84 348 180 Loss and loss expense incurred 584 333 1,166 654 Other insurance expenses Total defined benefit pension and post-retirement life 757 417 1,514 834 Income before federal income tax (159) (87) (318) (175) Total federal income tax expense 598 330 1,196 659 Net income Total reclassifications for the period $ 7,328 26,945 $ 5,221 57,329 Net income

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2023
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Quarter ended June 30, Six Months ended June 30, (in thousands, except per share amounts) 2023 2022 2023 2022 Net income available to common stockholders: $ 56,308 37,220 146,582 91,250 Weighted average common shares outstanding: Weighted average common shares outstanding - basic 60,614 60,440 60,575 60,412 Effect of dilutive securities - stock compensation plans 323 407 343 416 Weighted average common shares outstanding - diluted 60,937 60,847 60,918 60,828 EPS: Basic $ 0.93 0.62 2.42 1.51 Diluted 0.92 0.61 2.41 1.50

Statements of Cash Flows (Cash

Statements of Cash Flows (Cash Flow Supplemental Disclosures) (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022
Interest		$ 14,164	$ 14,240
Federal income tax		34,000	40,200
Operating cash flows from operating leases		4,038	4,086
Operating cash flows from financing leases		20	20
Financing cash flows from finance leases		1,231	1,202
Assets acquired under finance lease arrangements		0	41
Assets acquired under operating lease arrangements		4,509	5,781
Non-cash purchase of property and equipment		0	17
Available-for-sale Securities
Corporate actions related to securities	[1]	23,150	17,287
Equity Securities [Member]
Conversion of AFS fixed income securities to equity securities		$ 0	$ 1,463
[1]Examples of corporate actions include like-kind exchanges, non-cash acquisitions, and stock splits.

Statements of Cash Flows (Sched

Statements of Cash Flows (Schedule of Cash and Restricted Cash) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Schedule of Cash and Restricted Cash [Line Items]
Cash	$ 354	$ 26
Restricted cash	20,904	25,183
Total cash and restricted cash shown in the Consolidated Statements of Cash Flows	$ 21,258	$ 25,209	$ 7,566	$ 45,063

Investments (Available-For-Sale

Investments (Available-For-Sale Securities Disclosure) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	$ 7,564,942		$ 7,185,754
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(31,425)	$ (33,554)	(45,721)	$ (50,800)	$ (37,599)	$ (9,724)
Unrealized gains	11,110		9,262
Unrealized losses	(512,279)		(537,188)
Debt Securities, Available-for-sale, Fair Value	7,032,348		6,612,107
U.S. Government and Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	313,965		209,528
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	0		0
Unrealized gains	0		37
Unrealized losses	(20,943)		(20,326)
Debt Securities, Available-for-sale, Fair Value	293,022		189,239
Foreign Government [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	11,171		11,199
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(34)	(36)	(284)	(265)	(150)	(46)
Unrealized gains	0		0
Unrealized losses	(1,318)		(1,307)
Debt Securities, Available-for-sale, Fair Value	9,819		9,608
Obligations of States and Political Subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	694,734		965,231
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(769)	(737)	(1,024)	(1,206)	(1,991)	(137)
Unrealized gains	1,607		1,812
Unrealized losses	(37,544)		(48,001)
Debt Securities, Available-for-sale, Fair Value	658,028		918,018
Corporate Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	2,585,819		2,558,655
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(16,149)	(16,756)	(30,330)	(35,072)	(23,066)	(6,682)
Unrealized gains	4,964		3,509
Unrealized losses	(189,664)		(196,809)
Debt Securities, Available-for-sale, Fair Value	2,384,970		2,335,025
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	1,739,788		1,607,660
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(2,915)	(3,895)	(2,375)	(3,623)	(2,283)	(939)
Unrealized gains	3,353		2,408
Unrealized losses	(105,957)		(121,720)
Debt Securities, Available-for-sale, Fair Value	1,634,269		1,485,973
Residential Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	1,520,170		1,169,546
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(11,550)	(11,740)	(11,597)	(10,616)	(10,029)	(1,909)
Unrealized gains	1,024		1,148
Unrealized losses	(101,809)		(99,265)
Debt Securities, Available-for-sale, Fair Value	1,407,835		1,059,832
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed income securities, available-for-sale, amortized cost	699,295		663,935
Fixed Income Securities, Available-for-sale, Allowance for Credit Loss	(8)	$ (390)	(111)	$ (18)	$ (80)	$ (11)
Unrealized gains	162		348
Unrealized losses	(55,044)		(49,760)
Debt Securities, Available-for-sale, Fair Value	$ 644,405		$ 614,412

Investments (Available-for-sa_2

Investments (Available-for-sale allowance for credit losses roll forward) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	$ 33,554	$ 37,599	$ 45,721	$ 9,724
Current provision for securities without prior allowance	2,128	9,677	4,894	31,965
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	8,318
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(2,992)	5,842	(15,287)	5,605
Reductions for securities sold	(1,229)	(2,213)	(3,852)	(3,608)
Reductions for securities identified as intent (or requirement) to sell during the period	(36)	(105)	(51)	(1,204)
Allowance for Credit Losses, Period Ending Balance	31,425	50,800	31,425	50,800
Foreign Government [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	36	150	284	46
Current provision for securities without prior allowance	0	117	0	236
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	0
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(2)	12	(250)	(3)
Reductions for securities sold	0	(14)	0	(14)
Reductions for securities identified as intent (or requirement) to sell during the period	0	0	0	0
Allowance for Credit Losses, Period Ending Balance	34	265	34	265
Obligations of States and Political Subdivisions [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	737	1,991	1,024	137
Current provision for securities without prior allowance	67	534	67	1,237
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	0
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(35)	(1,166)	(239)	(4)
Reductions for securities sold	0	(153)	(83)	(164)
Reductions for securities identified as intent (or requirement) to sell during the period	0	0	0	0
Allowance for Credit Losses, Period Ending Balance	769	1,206	769	1,206
Corporate Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	16,756	23,066	30,330	6,682
Current provision for securities without prior allowance	1,438	8,323	4,141	28,243
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	0
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(1,070)	5,732	(14,884)	4,542
Reductions for securities sold	(939)	(1,944)	(3,387)	(3,191)
Reductions for securities identified as intent (or requirement) to sell during the period	(36)	(105)	(51)	(1,204)
Allowance for Credit Losses, Period Ending Balance	16,149	35,072	16,149	35,072
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	3,895	2,283	2,375	939
Current provision for securities without prior allowance	622	530	677	2,058
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	0
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(1,595)	819	(127)	637
Reductions for securities sold	(7)	(9)	(10)	(11)
Reductions for securities identified as intent (or requirement) to sell during the period	0	0	0	0
Allowance for Credit Losses, Period Ending Balance	2,915	3,623	2,915	3,623
Residential Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	11,740	10,029	11,597	1,909
Current provision for securities without prior allowance	1	173	8	174
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	8,318
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(50)	507	174	443
Reductions for securities sold	(141)	(93)	(229)	(228)
Reductions for securities identified as intent (or requirement) to sell during the period	0	0	0	0
Allowance for Credit Losses, Period Ending Balance	11,550	10,616	11,550	10,616
Commercial Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses, Period Beginning Balance	390	80	111	11
Current provision for securities without prior allowance	0	0	1	17
Initial Allowance for Purchased Credit Deteriorated Assets with Credit Deterioration	0	0	0	0
Increase (Decrease) on securities with prior allowance, excluding intent (or Requirements) to sell securities	(240)	(62)	39	(10)
Reductions for securities sold	(142)	0	(143)	0
Reductions for securities identified as intent (or requirement) to sell during the period	0	0	0	0
Allowance for Credit Losses, Period Ending Balance	$ 8	$ 18	$ 8	$ 18

Investments (Accrued Investment

Investments (Accrued Investment Income) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accrued Interest on Investments [Line Items]
Accrued investment income	$ 59,441	$ 59,167
Available-for-sale Securities [Member]
Accrued Interest on Investments [Line Items]
Accrued investment income	$ 58,100	$ 56,400

Investments (Fair Value and Gro

Investments (Fair Value and Gross Pre-Tax Net Unrealized Loss of Securities By Length of Time) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
U.S. Government and Government Agencies [Member]
AFS Fair Value, Less than 12 Months	$ 208,153	$ 166,975
AFS Unrealized Losses, Less than 12 months	(2,831)	(13,658)
AFS Fair Value, 12 months or longer	84,869	16,011
AFS Unrealized Losses, 12 months or longer	(18,112)	(6,668)
AFS Fair Value	293,022	182,986
AFS Unrealized Losses	(20,943)	(20,326)
Foreign Government [Member]
AFS Fair Value, Less than 12 Months	4,380	5,573
AFS Unrealized Losses, Less than 12 months	(247)	(608)
AFS Fair Value, 12 months or longer	5,439	2,456
AFS Unrealized Losses, 12 months or longer	(1,071)	(699)
AFS Fair Value	9,819	8,029
AFS Unrealized Losses	(1,318)	(1,307)
Obligations of States and Political Subdivisions [Member]
AFS Fair Value, Less than 12 Months	337,606	681,795
AFS Unrealized Losses, Less than 12 months	(5,554)	(43,767)
AFS Fair Value, 12 months or longer	229,922	16,618
AFS Unrealized Losses, 12 months or longer	(31,990)	(4,234)
AFS Fair Value	567,528	698,413
AFS Unrealized Losses	(37,544)	(48,001)
Corporate Securities [Member]
AFS Fair Value, Less than 12 Months	1,101,756	1,889,492
AFS Unrealized Losses, Less than 12 months	(40,711)	(164,197)
AFS Fair Value, 12 months or longer	895,497	133,223
AFS Unrealized Losses, 12 months or longer	(148,953)	(32,612)
AFS Fair Value	1,997,253	2,022,715
AFS Unrealized Losses	(189,664)	(196,809)
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
AFS Fair Value, Less than 12 Months	523,727	916,423
AFS Unrealized Losses, Less than 12 months	(17,268)	(69,155)
AFS Fair Value, 12 months or longer	924,490	411,283
AFS Unrealized Losses, 12 months or longer	(88,689)	(52,565)
AFS Fair Value	1,448,217	1,327,706
AFS Unrealized Losses	(105,957)	(121,720)
Residential Mortgage Backed Securities [Member]
AFS Fair Value, Less than 12 Months	792,885	887,229
AFS Unrealized Losses, Less than 12 months	(26,269)	(76,432)
AFS Fair Value, 12 months or longer	538,073	108,041
AFS Unrealized Losses, 12 months or longer	(75,540)	(22,833)
AFS Fair Value	1,330,958	995,270
AFS Unrealized Losses	(101,809)	(99,265)
Commercial Mortgage Backed Securities [Member]
AFS Fair Value, Less than 12 Months	291,078	512,953
AFS Unrealized Losses, Less than 12 months	(12,882)	(37,815)
AFS Fair Value, 12 months or longer	344,647	77,181
AFS Unrealized Losses, 12 months or longer	(42,162)	(11,945)
AFS Fair Value	635,725	590,134
AFS Unrealized Losses	(55,044)	(49,760)
Available-for-sale Securities [Member]
AFS Fair Value, Less than 12 Months	3,259,585	5,060,440
AFS Unrealized Losses, Less than 12 months	(105,762)	(405,632)
AFS Fair Value, 12 months or longer	3,022,937	764,813
AFS Unrealized Losses, 12 months or longer	(406,517)	(131,556)
AFS Fair Value	6,282,522	5,825,253
AFS Unrealized Losses	$ (512,279)	$ (537,188)

Investments (Fixed Income Secur

Investments (Fixed Income Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule of Fixed Income Securities [Line Items]
Due in one year or less fair value, AFS	$ 369,240
Due after one year through five years fair value, AFS	3,056,529
Due after five years through 10 years fair value, AFS	2,912,169
Due after 10 years fair value, AFS	694,410
Total AFS fixed income securities, Fair Value	7,032,348	$ 6,612,107
Due in one year or less carrying value, HTM	443
Due after one year through five years carrying value, HTM	13,942
Due after five years through 10 years carrying value, HTM	9,291
Due after 10 years carrying value, HTM	0
Fixed income securities, held-to-maturity, net of allowance for credit losses	23,676	31,157
Due in one year or less fair value, HTM	442
Due after one year through five years fair value, HTM	13,233
Due after five years through 10 years fair value, HTM	8,681
Due after 10 years fair value, HTM	0
Total HTM fixed income securities, Fair Value	$ 22,356	$ 29,837

Investments (Alternative Invest

Investments (Alternative Investment Portfolio by Strategy and the Remaining Commitment Amount and Maximum Exposure to Loss Associated With Each Strategy) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Carrying Amount	$ 389,173	$ 371,316
Private Equity Funds [Member]
Carrying Amount	298,219	280,980
Remaining Commitment	124,213	134,676
Maximum Exposure to Loss	422,432	415,656
Private Credit Funds [Member]
Carrying Amount	52,379	54,866
Remaining Commitment	138,691	89,481
Maximum Exposure to Loss	191,070	144,347
Real Assets [Member]
Carrying Amount	38,575	35,470
Remaining Commitment	19,553	21,945
Maximum Exposure to Loss	58,128	57,415
Alternative Investments [Member]
Carrying Amount	389,173	371,316
Remaining Commitment	282,457	246,102
Maximum Exposure to Loss	$ 671,630	$ 617,418

Investments (Aggregated Income

Investments (Aggregated Income Statement Summarized Financial Information for Partnerhips in our Alternative Investment Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 97,696	$ 70,222	$ 189,202	$ 142,824
Investments accounted for under the equity method [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income (loss)	(70,600)	270,900	(141,300)	406,500
Realized gains	922,000	6,233,500	2,644,300	8,981,500
Net change in unrealized appreciation (depreciation)	3,754,000	(3,962,400)	5,197,800	1,215,900
Net income	4,605,400	2,542,000	7,700,800	10,603,900
Alternative Investments [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 11,396	$ 9,274	$ 19,164	$ 28,402

Investments (Investments Pledge

Investments (Investments Pledged as Collateral) (Details) $ in Millions	Jun. 30, 2023 USD ($)
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral on deposit with various state and regulatory agencies	$ 22.9
Securities owned and pledged as collateral, fair value	123.5
Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	65
Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	35.6
U.S. Government and Government Agencies [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral on deposit with various state and regulatory agencies	19.4
Securities owned and pledged as collateral, fair value	19.4
U.S. Government and Government Agencies [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	0
U.S. Government and Government Agencies [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	0
Obligations of States and Political Subdivisions [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral on deposit with various state and regulatory agencies	3.5
Securities owned and pledged as collateral, fair value	3.5
Obligations of States and Political Subdivisions [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	0
Obligations of States and Political Subdivisions [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	0
Residential Mortgage Backed Securities [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral on deposit with various state and regulatory agencies	0
Securities owned and pledged as collateral, fair value	89
Residential Mortgage Backed Securities [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	62.1
Residential Mortgage Backed Securities [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	26.9
Commercial Mortgage Backed Securities [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral on deposit with various state and regulatory agencies	0
Securities owned and pledged as collateral, fair value	11.6
Commercial Mortgage Backed Securities [Member] | Federal Home Loan Bank of Indianapolis [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	2.9
Commercial Mortgage Backed Securities [Member] | Federal Home Loan Bank of New York [Member]
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral with FHLB	$ 8.7

Investments (Credit Concentrati

Investments (Credit Concentration Risk) (Details)	Jun. 30, 2023	Dec. 31, 2022
Investments [Abstract]
Maximum exposure to credit concentration risk of a single issuer of the Company's stockholder's equity, other than to certain U.S. government-backed investments	10%	10%

Investments (Net Investment Inc

Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net Investment Income [Line Items]
Net investment income earned	$ 97,696	$ 70,222	$ 189,202	$ 142,824
Fixed Income Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	83,916	62,144	164,003	116,069
Commercial Mortgage Loans [Member]
Net Investment Income [Line Items]
Net investment income earned	2,199	1,192	4,164	2,162
Equity Securities [Member]
Net Investment Income [Line Items]
Net investment income earned	2,236	2,639	3,441	5,057
Short-Term Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	2,892	407	7,542	508
Alternative Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	11,396	9,274	19,164	28,402
Other Investments [Member]
Net Investment Income [Line Items]
Net investment income earned	188	(214)	231	(37)
Investment expenses [Member]
Net Investment Income [Line Items]
Net investment income earned	$ (5,131)	$ (5,220)	$ (9,343)	$ (9,337)

Investments (Net Realized and U

Investments (Net Realized and Unrealized Investment Gains and (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Gain (Loss) on Securities [Line Items]
Gross gains on sales	$ 1,156	$ 14,552	$ 4,940	$ 16,749
Gross losses on sales	(11,952)	(19,345)	(24,882)	(32,905)
Net realized gains (losses) on disposals	(10,796)	(4,793)	(19,942)	(16,156)
Net unrealized gains (losses) on equity securities	4,925	(21,860)	8,173	(24,014)
Losses on securities for which we have the intent to sell	(341)	(702)	(645)	(5,499)
Net realized and unrealized investment gains (losses)	(5,426)	(42,880)	(2,082)	(83,232)
Available-for-sale Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss benefit (expense) on fixed income securities	864	(15,519)	10,393	(37,571)
Held-to-maturity Securities [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss benefit (expense) on fixed income securities	0	(6)	0	8
Commercial Mortgage Loans [Member]
Gain (Loss) on Securities [Line Items]
Net credit loss benefit (expense) on fixed income securities	$ (78)	$ 0	$ (61)	$ 0

Investments, Change in Realized

Investments, Change in Realized and Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023
Gain (Loss) on Securities [Line Items]
Change in net realized and unrealized investment losses	$ 37,500	$ 81,200

Investments (Realized and Unrea

Investments (Realized and Unrealized Gains (Losses) on Equity Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Gain (Loss) on Securities [Line Items]
Unrealized gains (losses) recognized in income on equity securities remaining in our portfolio at end of period	$ 2,784	$ (13,031)	$ 2,685	$ (14,843)
Unrealized gains (losses) recognized in income on equity securities sold in period	2,141	(8,829)	5,488	(9,171)
Total unrealized gains (losses) recognized in income on equity securities	$ 4,925	$ (21,860)	$ 8,173	$ (24,014)

Fair Value Measurements (Carryi

Fair Value Measurements (Carrying Values and Estimated Fair Values of Financial Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 503,622	$ 504,676
Long-term debt, fair value	486,858	466,603
Finance lease obligations	2,487	3,718
Seven Point Twenty Five Percent Senior Notes [Member] | Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	49,924	49,921
Seven Point Twenty Five Percent Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	52,312	51,705
Six Point Seventy Percent Senior Notes [Member] | Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	99,553	99,542
Six Point Seventy Percent Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	102,386	99,264
Five Point Three Hundred Seventy Five Senior Notes [Member] | Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	294,472	294,424
Five Point Three Hundred Seventy Five Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	275,149	258,459
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] | Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	60,000	60,000
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	57,011	57,175
Long Term Debt Excluding Issuance Costs and Finance Lease Obligations [Member] | Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	503,949	503,887
Unamortized Debt Issuance Costs [Member] | Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt issuance costs	$ (2,814)	$ (2,929)

Fair Value Measurements (Quanti

Fair Value Measurements (Quantitative Disclosures of Fair Value Assets) (Details) - USD ($) $ in Thousands		Jun. 30, 2023	Dec. 31, 2022
AFS fixed income securities		$ 7,032,348	$ 6,612,107
Equity securities		121,640	162,000
Short-term investments		319,456	440,456
Investments measured at fair value using the net asset value per share	[1]	97,900	103,600
Fair Value, Recurring [Member]
AFS fixed income securities		7,032,348	6,612,107
Equity securities		121,640	162,000
Short-term investments		319,456	440,456
Total assets measured at fair value		7,473,444	7,214,563
US Government and Government Agencies [Member]
AFS fixed income securities		293,022	189,239
US Government and Government Agencies [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		293,022	189,239
Foreign Government [Member]
AFS fixed income securities		9,819	9,608
Foreign Government [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		9,819	9,608
Obligations of States and Political Subdivisions [Member]
AFS fixed income securities		658,028	918,018
Obligations of States and Political Subdivisions [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		658,028	918,018
Corporate Securities [Member]
AFS fixed income securities		2,384,970	2,335,025
Corporate Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		2,384,970	2,335,025
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
AFS fixed income securities		1,634,269	1,485,973
Collateralized Loan Obligations and Other Asset Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		1,634,269	1,485,973
Residential Mortgage Backed Securities [Member]
AFS fixed income securities		1,407,835	1,059,832
Residential Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		1,407,835	1,059,832
Commercial Mortgage Backed Securities [Member]
AFS fixed income securities		644,405	614,412
Commercial Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		644,405	614,412
Common Stock [Member] | Fair Value, Recurring [Member]
Equity securities	[1]	119,867	160,355
Preferred Stock [Member] | Fair Value, Recurring [Member]
Equity securities		1,773	1,645
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		145,044	109,240
Equity securities		23,077	57,491
Short-term investments		315,574	418,199
Total assets measured at fair value		483,695	584,930
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | US Government and Government Agencies [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		145,044	109,240
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Foreign Government [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Corporate Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Common Stock [Member] | Fair Value, Recurring [Member]
Equity securities	[1]	21,304	55,846
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Preferred Stock [Member] | Fair Value, Recurring [Member]
Equity securities		1,773	1,645
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		6,432,796	6,154,509
Equity securities		0	0
Short-term investments		3,882	22,257
Total assets measured at fair value		6,436,678	6,176,766
Significant Other Observable Inputs (Level 2) [Member] | US Government and Government Agencies [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		147,978	79,999
Significant Other Observable Inputs (Level 2) [Member] | Foreign Government [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		9,819	9,608
Significant Other Observable Inputs (Level 2) [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		651,312	911,357
Significant Other Observable Inputs (Level 2) [Member] | Corporate Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		2,139,481	2,147,045
Significant Other Observable Inputs (Level 2) [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		1,432,343	1,332,631
Significant Other Observable Inputs (Level 2) [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		1,407,835	1,059,832
Significant Other Observable Inputs (Level 2) [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		644,028	614,037
Significant Other Observable Inputs (Level 2) [Member] | Common Stock [Member] | Fair Value, Recurring [Member]
Equity securities	[1]	0	0
Significant Other Observable Inputs (Level 2) [Member] | Preferred Stock [Member] | Fair Value, Recurring [Member]
Equity securities		0	0
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		454,508	348,358
Equity securities		662	897
Short-term investments		0	0
Total assets measured at fair value		455,170	349,255
Significant Unobservable Inputs (Level 3) [Member] | US Government and Government Agencies [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Government [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Significant Unobservable Inputs (Level 3) [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		6,716	6,661
Significant Unobservable Inputs (Level 3) [Member] | Corporate Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		245,489	187,980
Significant Unobservable Inputs (Level 3) [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		201,926	153,342
Significant Unobservable Inputs (Level 3) [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		0	0
Significant Unobservable Inputs (Level 3) [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Recurring [Member]
AFS fixed income securities		377	375
Significant Unobservable Inputs (Level 3) [Member] | Common Stock [Member] | Fair Value, Recurring [Member]
Equity securities	[1]	662	897
Significant Unobservable Inputs (Level 3) [Member] | Preferred Stock [Member] | Fair Value, Recurring [Member]
Equity securities		$ 0	$ 0
[1]Investments amounting to $97.9 million at June 30, 2023, and $103.6 million at December 31, 2022, were measured at fair value using the net asset value per share (or its practical expedient) and have not been classified in the fair value hierarchy. These investments are not redeemable and the timing of liquidations of the underlying assets is unknown at each reporting period. The fair value amounts in this table are intended to permit reconciliation of the fair value hierarchy to total assets measured at fair value.

Fair Value Measurements (Change

Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Obligations of States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	$ 6,661	$ 7,745
Total net gains (losses) for the period included in OCI	(7)	(581)
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers into Level 3	0	0
Transfers out of Level 3	0	0
Fair value, June 30	6,716	7,008
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	62	(156)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end	(7)	(581)
Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	187,980	114,127
Total net gains (losses) for the period included in OCI	1,857	(16,422)
Purchases	58,586	55,343
Sales	0	0
Issuances	0	0
Settlements	(5,535)	(3,903)
Transfers into Level 3	2,238	19,214
Transfers out of Level 3	0	(7,037)
Fair value, June 30	245,489	159,289
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	251	(2,047)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end	1,846	(16,424)
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	153,342	124,909
Total net gains (losses) for the period included in OCI	(1,168)	(8,592)
Purchases	39,713	39,133
Sales	0	0
Issuances	0	0
Settlements	(3,153)	(6,479)
Transfers into Level 3	14,148	0
Transfers out of Level 3	(953)	(24,646)
Fair value, June 30	201,926	123,616
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	17	(777)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end	(1,168)	(8,551)
Residential Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31		245
Total net gains (losses) for the period included in OCI		(17)
Purchases		0
Sales		0
Issuances		0
Settlements		(11)
Transfers into Level 3		0
Transfers out of Level 3		(217)
Fair value, June 30		0
Change in unrealized gains (losses) for the period included in earnings for assets held at period end		0
Change in unrealized gains (losses) for the period included in OCI for assets held at period end		(17)
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	375	4,256
Total net gains (losses) for the period included in OCI	64	(446)
Purchases	0	0
Sales	0	0
Issuances	0	0
Settlements	(21)	(12)
Transfers into Level 3	2,848	0
Transfers out of Level 3	(2,626)	(3,431)
Fair value, June 30	377	407
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	0	(7)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end	64	(446)
Common Stock [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	897
Total net gains (losses) for the period included in OCI	0
Purchases	0
Sales	0
Issuances	0
Settlements	0
Transfers into Level 3	0
Transfers out of Level 3	0
Fair value, June 30	662
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	(235)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end	0
Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, December 31	349,255	251,282
Total net gains (losses) for the period included in OCI	746	(26,058)
Purchases	98,299	94,476
Sales	0	0
Issuances	0	0
Settlements	(8,709)	(10,405)
Transfers into Level 3	19,234	19,214
Transfers out of Level 3	(3,579)	(35,331)
Fair value, June 30	455,170	290,320
Change in unrealized gains (losses) for the period included in earnings for assets held at period end	95	(2,987)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end	735	(26,019)
Gain (Loss) on Investments [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	62	(156)
Gain (Loss) on Investments [Member] | Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	251	(2,047)
Gain (Loss) on Investments [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	17	(777)
Gain (Loss) on Investments [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income		0
Gain (Loss) on Investments [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	0	(7)
Gain (Loss) on Investments [Member] | Common Stock [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	(235)
Gain (Loss) on Investments [Member] | Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	95	(2,987)
Net Investment Income Earned [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	0	0
Net Investment Income Earned [Member] | Corporate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	112	14
Net Investment Income Earned [Member] | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	(20)	68
Net Investment Income Earned [Member] | Residential Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income		0
Net Investment Income Earned [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	(263)	47
Net Investment Income Earned [Member] | Common Stock [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	0
Net Investment Income Earned [Member] | Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Total net gains (losses) for the period included in net income	$ (171)	$ 129

Fair Value (Quantitative inform

Fair Value (Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets) (Details) $ in Thousands		Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Level 3 Securities		$ 245,489	$ 187,980	$ 159,289	$ 114,127
Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Level 3 Securities		201,926	153,342	123,616	124,909
Valuation Technique, Discounted Cash Flow | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		116,155	81,867
Valuation Technique, Discounted Cash Flow | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		$ 90,768	$ 59,452
Valuation Technique, Discounted Cash Flow | Measurement Input, Credit Spread | Minimum | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Measurement Input		(0.044)	(0.044)
Valuation Technique, Discounted Cash Flow | Measurement Input, Credit Spread | Minimum | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.0001	0.0001
Valuation Technique, Discounted Cash Flow | Measurement Input, Credit Spread | Maximum | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.053	0.053
Valuation Technique, Discounted Cash Flow | Measurement Input, Credit Spread | Maximum | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.196	0.196
Valuation Technique, Discounted Cash Flow | Measurement Input, Credit Spread | Weighted Average | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.022	0.013
Valuation Technique, Discounted Cash Flow | Measurement Input, Credit Spread | Weighted Average | Collateralized Loan Obligations and Other Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.026	0.025
Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investment assets measured at fair value	[1]	$ 248,247	$ 207,936
Total Level 3 Securities		455,170	349,255	$ 290,320	$ 251,282
Investments [Member] | Valuation Technique, Discounted Cash Flow
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		$ 206,923	$ 141,319
[1]Other is comprised of broker quotes or other third-party pricing for which there is a lack of transparency into the inputs used to develop the valuations. The quantitative details of these unobservable inputs are neither provided to us, nor reasonably available to us, and therefore are not included in the tables above.

Fair Value Measurements (Quan_2

Fair Value Measurements (Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	$ 22,356	$ 29,837
Commercial mortgage loans, fair value	163,068	139,243
Long-term debt, fair value	486,858	466,603
Obligations of States and Political Subdivisions [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value		3,405
Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	22,356	26,432
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	0	0
Commercial mortgage loans, fair value	0	0
Long-term debt, fair value	0	0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value		0
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	22,356	29,837
Commercial mortgage loans, fair value	0	0
Long-term debt, fair value	486,858	466,603
Significant Other Observable Inputs (Level 2) [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value		3,405
Significant Other Observable Inputs (Level 2) [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	22,356	26,432
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	0	0
Commercial mortgage loans, fair value	163,068	139,243
Long-term debt, fair value	0	0
Significant Unobservable Inputs (Level 3) [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value		0
Significant Unobservable Inputs (Level 3) [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed income securities, held-to-maturity - fair value	0	0
Seven Point Twenty Five Percent Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	52,312	51,705
Seven Point Twenty Five Percent Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Seven Point Twenty Five Percent Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	52,312	51,705
Seven Point Twenty Five Percent Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Six Point Seventy Percent Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	102,386	99,264
Six Point Seventy Percent Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Six Point Seventy Percent Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	102,386	99,264
Six Point Seventy Percent Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Five Point Three Hundred Seventy Five Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	275,149	258,459
Five Point Three Hundred Seventy Five Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Five Point Three Hundred Seventy Five Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	275,149	258,459
Five Point Three Hundred Seventy Five Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	57,011	57,175
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	57,011	57,175
Three Point Zero Three Percent Borrowing From Federal Home Loan Bank Due December 16, 2026 [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	0	0
Long-term Debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 486,858	$ 466,603

Allowance for Credit Losses o_3

Allowance for Credit Losses on Premiums Receivable (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for Credit Losses on Premiums Receivable [Line Items]
Premium Receivable, Allowance for Credit Loss, Beginning Balance	$ 17,100	$ 14,300	$ 16,100	$ 13,600
Current period change for expected credit losses	1,515	1,169	3,425	2,085
Write-offs charged against the allowance for credit losses	(1,047)	(918)	(2,211)	(1,438)
Recoveries	332	349	586	653
Premium Receivable, Allowance for Credit Loss, Ending Balance	$ 17,900	$ 14,900	$ 17,900	$ 14,900

Reinsurance Recoverable Credit

Reinsurance Recoverable Credit Ratings (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance recoverable, gross	$ 648,591		$ 784,410
Reinsurance Recoverable, Allowance for Credit Loss	(1,800)	$ (2,300)	(1,600)	$ (1,600)	$ (1,600)	$ (1,600)
Reinsurance recoverable, net of allowance for credit losses	646,791		782,810
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	12,135		5,011
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	636,456		779,399
Total federal and state pools [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	80,629		180,794
Total federal and state pools [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	0		0
Total federal and state pools [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	80,629		180,794
Other than Federal And State Pools [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	7,192		14,093
Other than Federal And State Pools [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	475		415
Other than Federal And State Pools [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	6,717		13,678
Non Rated Reinsurer [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	87,821		194,887
Non Rated Reinsurer [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	475		415
Non Rated Reinsurer [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	87,346		194,472
AM Best, A++ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	81,005		46,283
AM Best, A++ Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	888		1
AM Best, A++ Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	80,117		46,282
AM Best, A+ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	353,169		428,586
AM Best, A+ Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	5,367		3,191
AM Best, A+ Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	347,802		425,395
AM Best, A Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	122,908		107,417
AM Best, A Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	5,316		1,315
AM Best, A Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	117,592		106,102
AM Best, A- Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	3,688		7,237
AM Best, A- Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	89		89
AM Best, A- Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	3,599		7,148
AM Best Rated Reinsurer [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	560,770		589,523
AM Best Rated Reinsurer [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	11,660		4,596
AM Best Rated Reinsurer [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	$ 549,110		$ 584,927

Reinsurance NFIP (Details)

Reinsurance NFIP (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
National Flood Insurance Program [Member]
Reinsurance NFIP [Line Items]
Percentage of unpaid NFIP Claims ceded to federal government	100%
Total federal and state pools [Member]
Reinsurance NFIP [Line Items]
Change in Reinsurance Recoverable, Gross	$ (100,200)

Allowance for Credit Losses o_4

Allowance for Credit Losses on Reinsurance Recoverable (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Reinsurance Recoverable, Allowance for Credit Loss [Line Items]
Allowance for credit losses, beginning balance	$ 2,300	$ 1,600	$ 1,600	$ 1,600
Current period change for expected credit losses	(500)	0	200	0
Write-offs charged against the allowance for credit losses	0	0	0	0
Recoveries	0	0	0	0
Allowance for credit losses, ending balance	$ 1,800	$ 1,600	$ 1,800	$ 1,600

Reinsurance (List of Direct, As

Reinsurance (List of Direct, Assumed, and Ceded Reinsurance Amounts) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Premiums earned:
Net	$ 942,150	$ 834,439	$ 1,844,486	$ 1,646,722
Loss and loss expenses incurred:
Net	646,130	524,868	1,213,568	1,019,104
Direct Assumed and Ceded Reinsurance Amounts [Member]
Premiums written:
Direct	1,232,496	1,050,506	2,365,256	2,051,555
Assumed	5,577	8,552	10,971	13,866
Ceded	(153,166)	(128,317)	(291,552)	(244,882)
Net	1,084,907	930,741	2,084,675	1,820,539
Premiums earned:
Direct	1,073,498	955,651	2,105,726	1,887,027
Assumed	5,968	7,481	12,258	13,009
Ceded	(137,316)	(128,693)	(273,498)	(253,314)
Net	942,150	834,439	1,844,486	1,646,722
Loss and loss expenses incurred:
Direct	698,994	559,913	1,312,223	1,088,501
Assumed	5,678	5,125	10,933	9,403
Ceded	(58,542)	(40,170)	(109,588)	(78,800)
Net	$ 646,130	$ 524,868	$ 1,213,568	$ 1,019,104

Reserve for Loss and Loss Exp_3

Reserve for Loss and Loss Expense (Rollforward of Reserve for Loss and Loss Expense) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Gross reserve for loss and loss expense, at beginning of period	$ 5,144,821	$ 4,580,903
Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of period	757,513	578,641
Net reserve for loss and loss expense, at beginning of period	4,387,308	4,002,262
Incurred loss and loss expense for claims occurring in the current year	1,221,635	1,041,778
Prior year development	(8,067)	(22,674)
Total incurred loss and loss expense	1,213,568	1,019,104
Paid loss and loss expense for claims occurring in the current year	320,026	272,401
Paid loss and loss expense for claims occurring in the prior years	720,314	570,868
Total paid loss and loss expense	1,040,340	843,269
Net reserve for loss and loss expense, at end of period	4,560,536	4,178,097
Add: reinsurance recoverable on unpaid loss and loss expense, at end of period	616,487	544,082
Gross reserve for loss and loss expense, at end of period	$ 5,177,023	$ 4,722,179

Reserve for Loss and Loss Exp_4

Reserve for Loss and Loss Expense (Reserve Loss Development) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	$ (8,067)	$ (22,674)
Change in Historical Claim Rate Experience [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	(8,100)	(22,700)
Change in Historical Claim Rate Experience [Member] | Casualty Insurance Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	(16,500)	(32,000)
Change in Historical Claim Rate Experience [Member] | Property Insurance [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	8,400	9,300
Change in Historical Claim Rate Experience [Member] | Workers' Compensation Insurance [Member] | Casualty Insurance Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	(17,500)	(20,000)
Change in Historical Claim Rate Experience [Member] | E&S Lines | Casualty Insurance Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	(5,000)
Change in Historical Claim Rate Experience [Member] | Personal Automobile [Member] | Casualty Insurance Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development	$ 6,000
Change in Historical Claim Rate Experience [Member] | General Liability [Member] | Casualty Insurance Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development		(5,000)
Change in Historical Claim Rate Experience [Member] | Surety Lines | Casualty Insurance Product Line [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year development		$ (7,000)

Segment Information Narrative (

Segment Information Narrative (Details)	6 Months Ended
	Jun. 30, 2023
Number of Operating Segments	4

Segment Information (Revenue by

Segment Information (Revenue by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Net premiums earned	$ 942,150	$ 834,439	$ 1,844,486	$ 1,646,722
Other income	6,104	3,037	8,738	4,566
Net investment income earned	97,696	70,222	189,202	142,824
Net realized and unrealized investment gains (losses)	(5,426)	(42,880)	(2,082)	(83,232)
Total Investments revenue	92,270	27,342	187,120	59,592
Total revenues	1,040,524	864,818	2,040,344	1,710,880
Standard Commercial Lines
Segment Reporting Information [Line Items]
Total revenues	768,277	682,833	1,502,073	1,345,403
Standard Commercial Lines | General Liability [Member]
Segment Reporting Information [Line Items]
Net premiums earned	254,510	226,285	497,859	442,610
Standard Commercial Lines | Commercial Automobile [Member]
Segment Reporting Information [Line Items]
Net premiums earned	225,067	198,381	442,438	392,211
Standard Commercial Lines | Commercial Property [Member]
Segment Reporting Information [Line Items]
Net premiums earned	141,348	123,562	276,640	243,624
Standard Commercial Lines | Workers Compensation [Member]
Segment Reporting Information [Line Items]
Net premiums earned	88,746	83,502	172,930	168,182
Standard Commercial Lines | Business Owners Policies [Member]
Segment Reporting Information [Line Items]
Net premiums earned	34,385	31,508	67,556	61,552
Standard Commercial Lines | Bonds Segment [Member]
Segment Reporting Information [Line Items]
Net premiums earned	11,619	10,682	23,016	21,042
Standard Commercial Lines | Other Commercial [Member]
Segment Reporting Information [Line Items]
Net premiums earned	7,034	6,317	13,885	12,485
Standard Commercial Lines | Miscellaneous income
Segment Reporting Information [Line Items]
Other income	5,568	2,596	7,749	3,697
Standard Personal Lines
Segment Reporting Information [Line Items]
Total revenues	87,706	73,779	170,029	146,849
Standard Personal Lines | Personal Automobile [Member]
Segment Reporting Information [Line Items]
Net premiums earned	48,230	39,952	93,144	79,668
Standard Personal Lines | Homeowners [Member]
Segment Reporting Information [Line Items]
Net premiums earned	36,902	31,630	71,915	62,817
Standard Personal Lines | Other Personal [Member]
Segment Reporting Information [Line Items]
Net premiums earned	2,038	1,756	3,981	3,495
Standard Personal Lines | Miscellaneous income
Segment Reporting Information [Line Items]
Other income	536	441	989	869
E&S Lines
Segment Reporting Information [Line Items]
Total revenues	92,271	80,864	181,122	159,036
E&S Lines | Casualty Insurance Product Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	62,151	56,041	122,968	110,665
E&S Lines | Property Insurance [Member]
Segment Reporting Information [Line Items]
Net premiums earned	$ 30,120	$ 24,823	$ 58,154	$ 48,371

Segment Information (Income Bef

Segment Information (Income Before and After Federal Income Tax) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Net investment income earned	$ 97,696	$ 70,222	$ 189,202	$ 142,824
Net realized and unrealized investment gains (losses)	(5,426)	(42,880)	(2,082)	(83,232)
Total investments segment income, before federal income tax	92,270	27,342	187,120	59,592
Tax on investments segment income	18,745	4,559	37,901	10,172
Total investments segment income, after federal income tax	73,525	22,783	149,219	49,420
Standard Commercial Lines
Segment Reporting Information [Line Items]
Underwriting income (loss), before federal income tax	22,146	46,708	61,067	89,092
Underwriting income (loss), after federal income tax	$ 17,495	$ 36,899	$ 48,243	$ 70,383
Combined ratio	97.10%	93.10%	95.90%	93.40%
ROE contribution	2.80%	6%	4.10%	5.50%
Standard Personal Lines
Segment Reporting Information [Line Items]
Underwriting income (loss), before federal income tax	$ (23,060)	$ (12,367)	$ (36,133)	$ (5,847)
Underwriting income (loss), after federal income tax	$ (18,217)	$ (9,770)	$ (28,545)	$ (4,619)
Combined ratio	126.50%	116.90%	121.40%	104%
ROE contribution	(2.90%)	(1.60%)	(2.40%)	(0.40%)
E&S Lines
Segment Reporting Information [Line Items]
Underwriting income (loss), before federal income tax	$ (612)	$ 3,372	$ 12,723	$ 10,297
Underwriting income (loss), after federal income tax	$ (483)	$ 2,664	$ 10,051	$ 8,135
Combined ratio	100.70%	95.80%	93%	93.50%
ROE contribution	(0.10%)	0.40%	0.80%	0.60%
Investments
Segment Reporting Information [Line Items]
ROE contribution	12.60%	9.10%	12.50%	8.90%

Segment Information (Reconcilia

Segment Information (Reconciliation of Segment Results to Income Before Federal Income Tax (Details)) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Investment income	$ 92,270	$ 27,342	$ 187,120	$ 59,592
Interest expense	(7,258)	(7,252)	(14,424)	(14,420)
Corporate expenses	(9,329)	(7,899)	(21,437)	(18,920)
Income before federal income tax	74,157	49,904	188,916	119,794
Preferred stock dividends	(2,300)	(2,300)	(4,600)	(4,600)
Income available to common stockholders, before federal income tax	71,857	47,604	184,316	115,194
Standard Commercial Lines
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Underwriting income (loss), before federal income tax	22,146	46,708	61,067	89,092
Standard Personal Lines
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Underwriting income (loss), before federal income tax	(23,060)	(12,367)	(36,133)	(5,847)
E&S Lines
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Underwriting income (loss), before federal income tax	(612)	3,372	12,723	10,297
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Underwriting income (loss), total all segments	$ 90,744	$ 65,055	$ 224,777	$ 153,134

Retirement Plans (Components of

Retirement Plans (Components of Net Periodic Benefit Cost) (Details) - Pension Plan [Member] - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Interest cost		$ 3,866	$ 2,486	$ 7,732	$ 4,972
Expected return on plan assets		(5,772)	(5,537)	(11,545)	(11,074)
Amortization of unrecognized net actuarial loss		750	367	1,501	733
Total net periodic pension cost (benefit)	[1]	$ (1,156)	$ (2,684)	$ (2,312)	$ (5,369)
[1]The components of net periodic pension cost (benefit) are included within "Loss and loss expense incurred" and "Other insurance expenses" on the Consolidated Statements of Income.

Retirement Plans (Weighted-Aver

Retirement Plans (Weighted-Average Expense Assumptions) (Details) - Pension Plan [Member]	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate	5.21%	2.98%
Effective interest rate for calculation of interest cost	5.09%	2.48%
Expected return on plan assets	6.90%	5%

Comprehensive Income (Component

Comprehensive Income (Components of Comprehensive Income-Gross and Net of Tax) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net income, Gross	$ 74,157	$ 49,904	$ 188,916	$ 119,794
Unrealized holding gains (losses) during the period, Gross	(60,681)	(222,903)	5,244	(484,735)
Unrealized gains (losses) on securities with credit loss recognized in earnings, Gross	(6,030)	(72,691)	16,401	(159,312)
Amounts reclassified into net income: HTM securities, Gross				1
Amounts reclassified into net income: net realized (gains) losses on disposals and intent-to-sell AFS securities, Gross	9,383	18,170	15,487	34,161
Amounts reclassified into net income: Credit loss (benefit) expense, Gross	(864)	15,519	(10,393)	37,571
Total unrealized gains (losses) on investment securities, Gross	(58,192)	(261,905)	26,739	(572,314)
Amount reclassified into net income: Net actuarial (gain) loss, Gross	757	417	1,514	834
Total defined benefit pension and post-retirement plans, Gross	757	417	1,514	834
Other comprehensive income (loss), Gross	(57,435)	(261,488)	28,253	(571,480)
Comprehensive income (loss), Gross	16,722	(211,584)	217,169	(451,686)
Net income, Tax	15,549	10,384	37,734	23,944
Unrealized holding gains (losses) during the period, Tax	(12,744)	(46,810)	1,102	(101,794)
Unrealized gains (losses) on securities with credit loss recognized in earnings, Tax	(1,266)	(15,264)	3,444	(33,455)
Amounts reclassified into net income: HTM securities, Tax				0
Amounts reclassified into net income: net realized (gains) losses on disposals and intent-to-sell AFS securities, Tax	1,970	3,816	3,252	7,174
Amounts reclassified into net income: Credit loss (benefit) expense, Tax	(181)	3,258	(2,183)	7,889
Total unrealized gains (losses) on investment securities, Tax	(12,221)	(55,000)	5,615	(120,186)
Amount reclassified into net income: Net actuarial (gain) loss, Tax	159	87	318	175
Total defined benefit pension and post-retirement plans, Tax	159	87	318	175
Other comprehensive income (loss), Tax	(12,062)	(54,913)	5,933	(120,011)
Comprehensive income (loss), Tax	3,487	(44,529)	43,667	(96,067)
Net income	58,608	39,520	151,182	95,850
Unrealized holding gains (losses) during the period, Net	(47,937)	(176,093)	4,142	(382,941)
Unrealized gains (losses) on securities with credit loss recognized in earnings, Net	(4,764)	(57,427)	12,957	(125,857)
Amounts reclassified into net income: HTM securities, Net	0	0	0	1
Amounts reclassified into net income: net realized (gains) losses on disposals and intent-to-sell AFS securities, Net	7,413	14,354	12,235	26,987
Amounts reclassified into net income: Credit loss (benefit) expense, Net	(683)	12,261	(8,210)	29,682
Total unrealized gains (losses) on investment securities	(45,971)	(206,905)	21,124	(452,128)
Amount reclassified into net income: Net actuarial (gain) loss, Net	598	330	1,196	659
Total defined benefit pension and post-retirement plans, Net	598	330	1,196	659
Other comprehensive income (loss)	(45,373)	(206,575)	22,320	(451,469)
Comprehensive income (loss)	$ 13,235	$ (167,055)	$ 173,502	$ (355,619)

Comprehensive Income (Compone_2

Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, December 31, 2022				$ (498,042)
Net current period OCI		$ (45,373)	$ (206,575)	22,320	$ (451,469)
Ending Balance, June 30, 2023		(475,722)		(475,722)
Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, December 31, 2022				(295,197)
OCI before reclassifications				4,142
Amounts reclassified from AOCI				12,235
Net current period OCI				16,377
Ending Balance, June 30, 2023		(278,820)		(278,820)
Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, December 31, 2022				(417,035)
OCI before reclassifications				17,099
Amounts reclassified from AOCI				4,025
Net current period OCI				21,124
Ending Balance, June 30, 2023		(395,911)		(395,911)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, December 31, 2022	[1]			(121,838)
OCI before reclassifications	[1]			12,957
Amounts reclassified from AOCI	[1]			(8,210)
Net current period OCI	[1]			4,747
Ending Balance, June 30, 2023	[1]	(117,091)		(117,091)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, December 31, 2022				(81,007)
OCI before reclassifications				0
Amounts reclassified from AOCI				1,196
Net current period OCI				1,196
Ending Balance, June 30, 2023		(79,811)		(79,811)
Accumulated other comprehensive income (loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance, December 31, 2022				(498,042)
OCI before reclassifications				17,099
Amounts reclassified from AOCI				5,221
Net current period OCI		(45,373)	$ (206,575)	22,320	$ (451,469)
Ending Balance, June 30, 2023		$ (475,722)		$ (475,722)
[1] 1 Represents change in unrealized gains (losses) on securities with credit loss recognized in earnings.

Comprehensive Income (Reclassif

Comprehensive Income (Reclassification out of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net realized and unrealized investment gains (losses)	$ (5,426)	$ (42,880)	$ (2,082)	$ (83,232)
Net investment income earned	97,696	70,222	189,202	142,824
Loss and loss expense incurred	646,130	524,868	1,213,568	1,019,104
Other insurance expenses	108,857	101,514	217,445	195,504
Income before federal income tax	74,157	49,904	188,916	119,794
Total federal income tax expense	(15,549)	(10,384)	(37,734)	(23,944)
Net income (loss)	58,608	39,520	151,182	95,850
Reclassification out of AOCI
Net income (loss)	7,328	26,945	5,221	57,329
Pension Plan [Member] | Reclassification out of AOCI
Loss and loss expense incurred	173	84	348	180
Other insurance expenses	584	333	1,166	654
Income before federal income tax	757	417	1,514	834
Total federal income tax expense	(159)	(87)	(318)	(175)
Net income (loss)	598	330	1,196	659
Held-to-maturity Securities [Member] | Reclassification out of AOCI
Net realized and unrealized investment gains (losses)	0	0	0	0
Net investment income earned	0	0	0	1
Income before federal income tax	0	0	0	1
Total federal income tax expense	0	0	0	0
Net income (loss)	0	0	0	1
Available for sale securities, excluding credit losses [Member] | Reclassification out of AOCI
Net realized and unrealized investment gains (losses)	9,383	18,170	15,487	34,161
Income before federal income tax	9,383	18,170	15,487	34,161
Total federal income tax expense	(1,970)	(3,816)	(3,252)	(7,174)
Net income (loss)	7,413	14,354	12,235	26,987
Available for sale securities, including credit losses | Reclassification out of AOCI
Net realized and unrealized investment gains (losses)	(864)	15,519	(10,393)	37,571
Income before federal income tax	(864)	15,519	(10,393)	37,571
Total federal income tax expense	181	(3,258)	2,183	(7,889)
Net income (loss)	$ (683)	$ 12,261	$ (8,210)	$ 29,682

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items]
Net income available to common stockholders	$ 56,308	$ 37,220	$ 146,582	$ 91,250
Weighted average common shares outstanding - basic	60,614	60,440	60,575	60,412
Effect of dilutive securities - stock compensation plans	323	407	343	416
Weighted average common shares outstanding, diluted	60,937	60,847	60,918	60,828
Earnings per common share - net income available to common stockholders - Basic	$ 0.93	$ 0.62	$ 2.42	$ 1.51
Earnings per common share - net income available to common stockholders - Diluted	$ 0.92	$ 0.61	$ 2.41	$ 1.50