ProAssurance (PRA) 10-Q 8 Aug 23 2023 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2023	Aug. 03, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	0-16533
Entity Registrant Name	ProAssurance Corporation
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	63-1261433
Entity Address, Address Line One	100 Brookwood Place,
Entity Address, City or Town	Birmingham,
Entity Address, State or Province	AL
Entity Address, Postal Zip Code	35209
City Area Code	(205)
Local Phone Number	877-4400
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	PRA
Security Exchange Name	NYSE
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 (in shares)		52,064,808
Entity Central Index Key	0001127703
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Investments
Fixed maturities, available-for-sale, at fair value (amortized cost, $3,699,049 and $3,852,411, respectively; allowance for expected credit losses, $419 as of June 30, 2023 and $427 as of December 31, 2022)	$ 3,352,331	$ 3,472,472
Fixed maturities, trading, at fair value (cost, $45,455 and $45,048, respectively)	45,732	43,434
Equity investments, at fair value (cost, $165,612 and $162,429, respectively)	149,529	143,738
Short-term investments	315,581	245,313
Business owned life insurance	80,930	81,746
Investment in unconsolidated subsidiaries	306,027	305,210
Other investments (at fair value, $62,287 and $92,447, respectively, otherwise at cost or amortized cost)	65,287	95,770
Total Investments	4,315,417	4,387,683
Cash and cash equivalents	46,034	29,959
Premiums receivable (allowance for expected credit losses, $7,876 as of June 30, 2023 and $7,658 as of December 31, 2022)	258,867	246,094
Receivable from reinsurers on paid losses and loss adjustment expenses	26,651	15,313
Receivable from reinsurers on unpaid losses and loss adjustment expenses	425,560	431,889
Prepaid reinsurance premiums	34,327	29,120
Deferred policy acquisition costs	62,999	58,148
Deferred tax asset, net	202,165	209,535
Real estate, net	30,202	29,968
Operating lease ROU assets	17,032	18,987
Intangible assets, net	63,571	66,835
Goodwill	49,610	49,610
Other assets	124,977	126,858
Total Assets	5,657,412	5,699,999
Policy liabilities and accruals
Reserve for losses and loss adjustment expenses	3,420,925	3,471,147
Unearned premiums	439,556	422,950
Reinsurance premiums payable	27,184	28,514
Total Policy Liabilities and Accruals	3,887,665	3,922,611
Operating lease liabilities	17,912	20,008
Other liabilities	206,095	226,379
Debt less unamortized debt issuance costs	426,026	426,983
Total Liabilities	4,537,698	4,595,981
Shareholders' Equity
Common shares (par value $0.01 per share, 100,000,000 shares authorized, 63,575,853 and 63,427,796 shares issued, respectively)	636	634
Additional paid-in capital	400,705	397,919
Accumulated other comprehensive income (loss) (net of deferred tax expense (benefit) of ($72,739) and ($80,810), respectively)	(267,480)	(298,607)
Retained earnings	1,425,038	1,423,286
Treasury shares, at cost (10,857,458 and 9,464,160 shares, respectively)	(439,185)	(419,214)
Total Shareholders' Equity	1,119,714	1,104,018
Total Liabilities and Shareholders' Equity	$ 5,657,412	$ 5,699,999

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Available for sale securities, amortized cost	$ 3,699,049	$ 3,852,411
Allowance for expected credit losses	419	427
Trading securities, cost	45,455	45,048
Equity investments at fair value, cost	165,612	162,429
Other investments, portion carried at fair value	62,287	92,447
Premium receivable, allowance for credit loss	$ 7,876	$ 7,658
Common shares, par value (in usd per share)	$ 0.01	$ 0.01
Common shares, shares authorized (in shares)	100,000,000	100,000,000
Common shares, shares issued (in shares)	63,575,853	63,427,796
Deferred tax expense (benefit) on accumulated other comprehensive income (loss)	$ (72,739)	$ (80,810)
Treasury shares (in shares)	10,857,458	9,464,160

Condensed Consolidated Statemen

Condensed Consolidated Statements of Changes in Capital (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Increase (Decrease) in Stockholders' Equity:
Beginning balance	$ 1,138,290	$ 1,281,768	$ 1,104,018	$ 1,428,387
Common shares reacquired	(19,971)		(19,971)
Common shares issued for compensation	1,054	1,061	1,064	1,068
Share-based compensation	1,228	1,048	2,374	2,390
Net effect of restricted and performance shares issued	(12)	(2)	(650)	(858)
Dividends to shareholders		(2,705)	(2,701)	(5,407)
Other comprehensive income (loss)	(11,502)	(109,622)	31,127	(250,472)
Net income (loss)	10,627	(1,659)	4,453	(5,219)
Ending balance	1,119,714	1,169,889	1,119,714	1,169,889
Common Stock
Increase (Decrease) in Stockholders' Equity:
Beginning balance	635	634	634	633
Net effect of restricted and performance shares issued	1		2	1
Ending balance	636	634	636	634
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity:
Beginning balance	398,436	393,433	397,919	392,941
Common shares issued for compensation	1,054	1,061	1,064	1,068
Share-based compensation	1,228	1,048	2,374	2,390
Net effect of restricted and performance shares issued	(13)	(2)	(652)	(859)
Ending balance	400,705	395,540	400,705	395,540
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity:
Beginning balance	(255,978)	(124,566)	(298,607)	16,284
Other comprehensive income (loss)	(11,502)	(109,622)	31,127	(250,472)
Ending balance	(267,480)	(234,188)	(267,480)	(234,188)
Retained Earnings
Increase (Decrease) in Stockholders' Equity:
Beginning balance	1,414,411	1,428,229	1,423,286	1,434,491
Dividends to shareholders		(2,705)	(2,701)	(5,407)
Net income (loss)	10,627	(1,659)	4,453	(5,219)
Ending balance	1,425,038	1,423,865	1,425,038	1,423,865
Treasury Stock
Increase (Decrease) in Stockholders' Equity:
Beginning balance	(419,214)	(415,962)	(419,214)	(415,962)
Common shares reacquired	(19,971)		(19,971)
Ending balance	$ (439,185)	$ (415,962)	$ (439,185)	$ (415,962)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Income and Comprehensive Income (Unaudited) - USD ($) shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenues
Net premiums earned	$ 247,862,000	$ 247,271,000	$ 487,649,000	$ 512,982,000
Net investment income	31,650,000	21,944,000	61,960,000	42,387,000
Equity in earnings (loss) of unconsolidated subsidiaries	6,632,000	5,180,000	5,511,000	12,799,000
Net investment gains (losses):
Impairment losses	43,000	972,000	2,976,000	972,000
Portion of impairment losses recognized in other comprehensive income (loss) before taxes	0	419,000	0	419,000
Net impairment losses recognized in earnings	43,000	553,000	2,976,000	553,000
Other net investment gains (losses)	2,989,000	(23,331,000)	8,834,000	(36,837,000)
Total net investment gains (losses)	2,946,000	(23,884,000)	5,858,000	(37,390,000)
Other income	2,741,000	5,314,000	3,528,000	8,119,000
Total revenues	291,831,000	255,825,000	564,506,000	538,897,000
Expenses
Net losses and loss adjustment expenses	191,058,000	177,670,000	396,354,000	387,093,000
Underwriting, policy acquisition and operating expenses:
Operating expense	42,177,000	42,938,000	77,261,000	81,748,000
DPAC amortization	34,799,000	34,395,000	67,503,000	67,361,000
SPC U.S. federal income tax expense	994,000	349,000	1,526,000	991,000
SPC dividend expense (income)	3,747,000	(854,000)	5,689,000	1,513,000
Interest expense	5,502,000	4,919,000	10,965,000	9,360,000
Total expenses	278,277,000	259,417,000	559,298,000	548,066,000
Income (loss) before income taxes	13,554,000	(3,592,000)	5,208,000	(9,169,000)
Provision for income taxes:
Current expense (benefit)	319,000	65,000	776,000	(542,000)
Deferred expense (benefit)	2,608,000	(1,998,000)	(21,000)	(3,408,000)
Total income tax expense (benefit)	2,927,000	(1,933,000)	755,000	(3,950,000)
Net income (loss)	10,627,000	(1,659,000)	4,453,000	(5,219,000)
Other comprehensive income (loss), after tax, net of reclassification adjustments	(11,502,000)	(109,622,000)	31,127,000	(250,472,000)
Comprehensive income (loss)	$ (875,000)	$ (111,281,000)	$ 35,580,000	$ (255,691,000)
Earnings (loss) per share:
Basic (in usd per share)	$ 0.20	$ (0.03)	$ 0.08	$ (0.10)
Diluted (in usd per share)	$ 0.20	$ (0.03)	$ 0.08	$ (0.10)
Weighted average number of common shares outstanding:
Basic (in shares)	53,815	54,068	53,900	54,040
Diluted (in shares)	53,918	54,186	54,017	54,165
Cash dividends declared per common share (in usd per share)	$ 0	$ 0.05	$ 0.05	$ 0.10

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating Activities
Net income (loss)	$ 4,453	$ (5,219)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization, net of accretion	13,631	20,409
(Increase) decrease in cash surrender value of BOLI	816	949
Net investment (gains) losses	(5,858)	37,390
Share-based compensation	2,374	2,392
Deferred income tax expense (benefit)	(21)	(3,408)
Policy acquisition costs, net of amortization (net deferral)	(4,851)	(4,173)
Equity in (earnings) loss of unconsolidated subsidiaries	(5,511)	(12,799)
Distributed earnings from unconsolidated subsidiaries	4,678	19,240
Other, net	913	(507)
Change in:
Premiums receivable	(12,773)	(3,955)
Reinsurance related assets and liabilities	(11,546)	(15,899)
Other assets	(328)	10,756
Reserve for losses and loss adjustment expenses	(50,222)	(7,078)
Unearned premiums	16,606	16,610
Other liabilities	(14,203)	(58,379)
Net cash provided (used) by operating activities	(61,842)	(3,671)
Purchases of:
Fixed maturities, available-for-sale	(134,223)	(340,746)
Equity investments	(932)	(30,266)
Other investments	(14,645)	(17,136)
Investment in unconsolidated subsidiaries	(16,072)	(20,129)
Proceeds from sales or maturities of:
Fixed maturities, available-for-sale	275,630	308,285
Equity investments	1,026	74,700
Other investments	47,257	10,930
Net sales or (purchases) of fixed maturities, trading	(2,253)	(2,449)
Return of invested capital from unconsolidated subsidiaries	16,087	27,352
Net sales or maturities (purchases) of short-term investments	(68,927)	(109,566)
Unsettled security transactions, net change	2,439	11,507
Purchases of capital assets	(2,120)	(2,232)
Other	2,659	(1,363)
Net cash provided (used) by investing activities	105,926	(91,113)
Financing Activities
Repurchase of common stock	(19,971)	0
Dividends to shareholders	(5,379)	(8,080)
Capital contribution received from (return of capital to) external segregated portfolio cell participants	50	(7,117)
Other	(2,709)	1,211
Net cash provided (used) by financing activities	(28,009)	(13,986)
Increase (decrease) in cash and cash equivalents	16,075	(108,770)
Cash and cash equivalents at beginning of period	29,959	143,602
Cash and cash equivalents at end of period	46,034	34,832
Significant Non-Cash Transactions
Increase (decrease) in fair value of contingent consideration issued in NORCAL acquisition	$ (4,000)	$ 0

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of ProAssurance Corporation, its wholly owned subsidiaries and VIEs in which ProAssurance is the primary beneficiary (ProAssurance, PRA or the Company). See Note 10 for more information on ProAssurance's VIE interests. The financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation, consisting of normal recurring adjustments, have been included. ProAssurance’s results for the six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The accompanying Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and Notes contained in ProAssurance’s December 31, 2022 report on Form 10-K. ProAssurance operates in five reportable segments as follows: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance, Lloyd's Syndicates and Corporate. For more information on the Company's segment reporting, including the nature of products and services provided and financial information by segment, refer to Note 12. Accounting Policies The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and disclosures related to these amounts at the date of the financial statements. The Company evaluates these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that the Company believes to be reasonable under the circumstances. The Company can make no assurance that actual results will conform to its estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions. Other than as disclosed below, the significant accounting policies followed by ProAssurance in making estimates that materially affect financial reporting are summarized in Note 1 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K. Derivatives ProAssurance records derivative instruments at fair value in the Condensed Consolidated Balance Sheets. ProAssurance accounts for the changes in fair value of derivatives depending on whether the derivative is designated as a hedging instrument and if so, the type of hedging relationship. For derivative instruments not designated as hedging instruments, ProAssurance recognizes the change in fair value of the derivative in earnings during the period of change. ProAssurance does not use derivative instruments for trading purposes. For derivative financial instruments designed as cash flow hedges, ProAssurance formally documents all relationships between the hedging instruments and the hedged items as well as its risk-management objective and strategy for undertaking various hedged transactions. ProAssurance also formally assesses, both at the hedge's inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in cash flows of hedged items. When it is determined that a derivative is not highly effective as a hedge or that it has ceased to be a highly effective hedge, ProAssurance discontinues hedge accounting prospectively. As of June 30, 2023, ProAssurance uses Interest Rate Swaps that are designated and qualify as highly effective cash flow hedges to manage its exposure to variability in cash flows of forecasted interest payments attributable to variability in the selected base rates on borrowings under the amended Revolving Credit Agreement. Changes in the fair value of derivatives that are designated and qualify as highly effective cash flow hedges are recorded in AOCI, net of tax, and are reclassified into earnings when the hedged cash flows impact earnings. When the change in the fair value of a qualifying cash flow hedge is included in earnings, it is included in the same line item on the Condensed Consolidated Statement of Income and Comprehensive Income as the cash flows from the hedged item. The Company has elected not to offset fair value amounts recognized for the Interest Rate Swaps and fair value of the amounts recognized to reclaim cash collateral or the obligation to return cash collateral executed with counterparties under a master netting arrangement. The cash flows of derivatives used in hedging relationships are classified as either operating, investing, or financing cash flows based on the classification of the hedged item. Accounting Changes Adopted Reference Rate Reform - Deferral of LIBOR Sunset Date (ASU 2022-06) Effective for fiscal years beginning after December 31, 2022 and interim periods within those fiscal years, the FASB amended guidance which defers the LIBOR transition date from December 31, 2022 to December 31, 2024. ProAssurance has exposure to LIBOR in its available-for-sale fixed maturities portfolio which represented approximately 1% of total investments, or $60 million as of June 30, 2023; 73% of these investments with exposure to LIBOR were issued since 2020 and include provisions for an alternative benchmark rate. ProAssurance adopted the guidance beginning January 1, 2023, and adoption had no material effect on ProAssurance's results of operations, financial position or cash flows. Presentation of Financial Statements, Income Statement—Reporting Comprehensive Income, Distinguishing Liabilities from Equity, Equity and Compensation—Stock Compensation (ASU 2023-03) Effective immediately, the FASB amended guidance on July 14, 2023 to align various SEC paragraphs in the Codification to reflect the issuance of SEC Staff Accounting Bulletin No. 120, among other things. ProAssurance adopted the guidance beginning July 14, 2023, and adoption had no material effect on ProAssurance's results of operations, financial position or cash flows. Accounting Changes Not Yet Adopted ProAssurance is not aware of any accounting changes not yet adopted as of June 30, 2023 that could have a material impact on its results of operations, financial position or cash flows. Employee Retention Credit In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations, including the initial version of the ERC. In December 2020 and March 2021, the ERC was extended and expanded from 50% of qualified wages to 70%. The 2020 rules limited qualified wages to $10,000 per employee and applied to employers with 100 or fewer full-time employees in 2019. The rules were expanded in 2021 to raise the qualified wage limit to $10,000 per employee, per quarter. As an eligible employer, NORCAL filed a claim during the second quarter of 2023 for a payroll tax refund of approximately $3.8 million. The Company recorded the expected payroll tax refund as a component of operating expenses on the Condensed Consolidated Statements of Income and Comprehensive Income for the six months ended June 30, 2023 and as a component of other assets on the Condensed Consolidated Balance Sheets as of June 30, 2023.

Fair Value Measurement

Fair Value Measurement	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. A three level hierarchy has been established for valuing assets and liabilities based on how transparent (observable) the inputs are that are used to determine fair value, with the inputs considered most observable categorized as Level 1 and those that are the least observable categorized as Level 3. Hierarchy levels are defined as follows: Level 1: quoted (unadjusted) market prices in active markets for identical assets and liabilities. For ProAssurance, Level 1 inputs are generally quotes for securities actively traded in exchange or over-the-counter markets. Level 2: market data obtained from sources independent of the reporting entity (observable inputs). For ProAssurance, Level 2 inputs generally include quoted prices in markets that are not active, quoted prices for similar assets or liabilities, and results from pricing models that use observable inputs such as interest rates and yield curves that are generally available at commonly quoted intervals. Level 3: the reporting entity’s own assumptions about market participant assumptions based on the best information available in the circumstances (non-observable inputs). For ProAssurance, Level 3 inputs are used in situations where little or no Level 1 or 2 inputs are available or are inappropriate given the particular circumstances. Level 3 inputs include results from pricing models for which some or all of the inputs are not observable, discounted cash flow methodologies, single non-binding broker quotes and adjustments to externally quoted prices that are based on management judgment or estimation. Fair values of assets measured at fair value on a recurring basis as of June 30, 2023 and December 31, 2022 are shown in the following tables. Where applicable, the tables also indicate the fair value hierarchy of the valuation techniques utilized to determine those fair values. For some assets, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. When this is the case, the asset is categorized based on the level of the most significant input to the fair value measurement. Assessments of the significance of a particular input to the fair value measurement require judgment and consideration of factors specific to the assets being valued. For more information on the valuation methodologies used regarding securities in the Level 2 and Level 3 categories, see Note 3 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K. June 30, 2023 Fair Value Measurements Using Total (In thousands) Level 1 Level 2 Level 3 Fair Value Assets: Fixed maturities, available-for-sale U.S. Treasury obligations $ — $ 230,214 $ — $ 230,214 U.S. Government-sponsored enterprise obligations — 18,863 — 18,863 State and municipal bonds — 440,231 — 440,231 Corporate debt, multiple observable inputs — 1,621,785 — 1,621,785 Corporate debt, limited observable inputs — — 67,394 67,394 Residential mortgage-backed securities — 376,263 288 376,551 Agency commercial mortgage-backed securities — 8,764 — 8,764 Other commercial mortgage-backed securities — 190,012 — 190,012 Other asset-backed securities — 397,576 941 398,517 Fixed maturities, trading — 45,732 — 45,732 Equity investments Financial 9,884 2,219 288 12,391 Utilities/Energy 892 — — 892 Industrial — — 4,946 4,946 Bond funds 113,164 — — 113,164 All other 18,136 — — 18,136 Short-term investments 205,896 109,685 — 315,581 Other investments 1,106 60,681 500 62,287 Other assets — 5,455 — 5,455 Total assets categorized within the fair value hierarchy $ 349,078 $ 3,507,480 $ 74,357 3,930,915 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Investment in unconsolidated subsidiaries 270,495 Total assets at fair value $ 4,201,410 Liabilities: Other liabilities $ 5,450 $ — $ 11,000 $ 16,450 Total liabilities categorized within the fair value hierarchy $ 5,450 $ — $ 11,000 $ 16,450 December 31, 2022 Fair Value Measurements Using Total (In thousands) Level 1 Level 2 Level 3 Fair Value Assets: Fixed maturities, available-for-sale U.S. Treasury obligations $ — $ 221,608 $ — $ 221,608 U.S. Government-sponsored enterprise obligations — 19,934 — 19,934 State and municipal bonds — 439,450 — 439,450 Corporate debt, multiple observable inputs — 1,717,479 — 1,717,479 Corporate debt, limited observable inputs — — 63,973 63,973 Residential mortgage-backed securities — 389,291 249 389,540 Agency commercial mortgage-backed securities — 9,704 — 9,704 Other commercial mortgage-backed securities — 194,090 — 194,090 Other asset-backed securities — 413,989 2,705 416,694 Fixed maturities, trading — 43,434 — 43,434 Equity investments Financial 9,850 2,219 303 12,372 Utilities/Energy 854 — — 854 Industrial — — 2,500 2,500 Bond funds 112,136 — — 112,136 All other 15,876 — — 15,876 Short-term investments 181,937 63,376 — 245,313 Other investments 1,881 88,783 1,783 92,447 Total assets categorized within the fair value hierarchy $ 322,534 $ 3,603,357 $ 71,513 3,997,404 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Investment in unconsolidated subsidiaries 262,485 Total assets at fair value $ 4,259,889 Liabilities: Other liabilities $ — $ — $ 15,000 $ 15,000 Total liabilities categorized within the fair value hierarchy $ — $ — $ 15,000 $ 15,000 Level 2 Valuations Other than as described below, see Note 3 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K for a summary description of the valuation methodologies used regarding securities in the Level 2 category, by security type. Level 2 Valuation Methodologies Other assets consisted of interest rate swap derivative instruments valued using a model which considers the volatilities from other instruments with similar maturities, strike prices and durations. Level 3 Valuations See Note 3 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K for a summary description of the valuation methodologies used regarding securities in the Level 3 category, by security type. Quantitative Information Regarding Level 3 Valuations Below is a quantitative information regarding securities in the Level 3 category, by security type: Fair Value at ($ in thousands) June 30, 2023 December 31, 2022 Valuation Technique Unobservable Input Range Assets: Corporate debt, limited observable inputs $67,394 $63,973 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Residential mortgage-backed securities $288 $249 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other asset-backed securities $941 $2,705 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Equity investments $5,234 $2,803 Discounted Cash Flows Comparability Adjustment 0% - 10% (5%) Other investments $500 $1,783 Discounted Cash Flows Comparability Adjustment 0% - 10% (5%) Liabilities: Other liabilities $11,000 $15,000 Stochastic Model/Discounted Cash Flows Weighted Average Cost of Capital 0% - 10% (9%) The significant unobservable inputs used in the fair value measurement of the above listed securities were the valuations of comparable securities with similar issuers, credit quality and maturity. Changes in the availability of comparable securities could result in changes in the fair value measurements. Fair Value Measurements - Level 3 Assets & Liabilities The following tables present summary information regarding changes in the fair value of assets and liabilities measured using Level 3 inputs. June 30, 2023 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Other Liabilities Total Liabilities Balance, March 31, 2023 $ 76,157 $ 5,054 $ 2,800 $ 500 $ 84,511 $ (13,000) $ (13,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (loss) (23) — — — (23) — — Net investment gains (losses) (3) — (737) — (740) 2,000 2,000 Included in other comprehensive income (loss) (142) (13) — — (155) — — Purchases 4,084 — 3,171 — 7,255 — — Sales (3,595) (396) — — (3,991) — — Transfers out (9,084) (3,416) — — (12,500) — — Balance, June 30, 2023 $ 67,394 $ 1,229 $ 5,234 $ 500 $ 74,357 $ (11,000) $ (11,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ (737) $ — $ (737) $ — $ — June 30, 2023 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Assets Other Liabilities Total Liabilities Balance, December 31, 2022 $ 63,973 $ 2,954 $ 2,803 $ 1,783 $ 71,513 $ (15,000) $ (15,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (loss) (23) — — — (23) — — Net investment gains (losses) 13 — (740) — (727) 3,000 3,000 Operating expense — — — — — 1,000 1,000 Included in other comprehensive income (loss) 67 26 — — 93 — — Purchases 10,406 1,863 3,171 — 15,440 — — Sales (4,027) (396) — — (4,423) — — Transfers in 11,220 1,779 — — 12,999 — — Transfers out (14,235) (4,997) — (1,283) (20,515) — — Balance, June 30, 2023 $ 67,394 $ 1,229 $ 5,234 $ 500 $ 74,357 $ (11,000) $ (11,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ (740) $ — $ (740) $ — $ — June 30, 2022 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Other Liabilities Total Liabilities Balance, March 31, 2022 $ 53,325 $ 9,303 $ 2,500 $ 3,440 $ 68,568 $ (24,000) $ (24,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment gains (losses) — — — (787) (787) — — Included in other comprehensive income (loss) (1,319) (177) — — (1,496) — — Purchases 8,787 1,473 — — 10,260 — — Sales (2,007) (192) — — (2,199) — — Transfers in 17,828 570 2,125 — 20,523 — — Transfers out (2,402) (6,939) — (1,752) (11,093) — — Balance, June 30, 2022 $ 74,212 $ 4,038 $ 4,625 $ 901 $ 83,776 $ (24,000) $ (24,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ — $ (787) $ (787) $ — $ — June 30, 2022 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Assets Other Liabilities Total Liabilities Balance, December 31, 2021 $ 47,129 $ 6,502 $ 2,500 $ 1,434 $ 57,565 $ (24,000) $ (24,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (loss) — 1 — — 1 — — Net investment gains (losses) — — — (677) (677) — — Included in other comprehensive income (loss) (2,312) (437) — — (2,749) — — Purchases 18,498 7,058 — 1,483 27,039 — — Sales (3,026) (197) — (116) (3,339) — — Transfers in 18,828 570 2,125 529 22,052 — — Transfers out (4,905) (9,459) — (1,752) (16,116) — — Balance, June 30, 2022 $ 74,212 $ 4,038 $ 4,625 $ 901 $ 83,776 $ (24,000) $ (24,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ — $ (723) $ (723) $ — $ — Transfers Transfers shown in the preceding Level 3 tables were as of the end of the period in which the transfer occurred. All transfers were to or from Level 2. All transfers in and out of Level 3 during the three and six months ended June 30, 2023 and 2022 related to securities held for which the level of market activity for identical or nearly identical securities varies from period to period. The securities were valued using multiple observable inputs when those inputs were available; otherwise the securities were valued using limited observable inputs. Fair Values Not Categorized At June 30, 2023 and December 31, 2022, certain LPs/LLCs and investment funds measure fund assets at fair value on a recurring basis and provide a NAV for ProAssurance's interest. The carrying value of these interests is based on the NAV provided and was considered to approximate the fair value of the interests. For investment in unconsolidated subsidiaries, ProAssurance recognizes any changes in the NAV of its interests in equity in earnings (loss) of unconsolidated subsidiaries during the period of change. In accordance with GAAP, the fair value of these investments was not classified within the fair value hierarchy. The amount of ProAssurance's unfunded commitments related to these investments as of June 30, 2023 and fair values of these investments as of June 30, 2023 and December 31, 2022 were as follows: Unfunded Fair Value (In thousands) June 30, June 30, December 31, Investment in unconsolidated subsidiaries: Private debt funds (1) $1,885 $ 19,970 $ 19,620 Long/short equity funds (2) None 4,876 5,089 Non-public equity funds (3) $51,582 144,908 144,560 Credit funds (4) $31,251 50,178 49,245 Strategy focused funds (5) $9,016 50,563 43,971 Total investments carried at NAV $ 270,495 $ 262,485 Below is additional information regarding each of the investments listed in the table above as of June 30, 2023. (1) This investment is comprised of interests in two unrelated LP funds that are structured to provide interest distributions primarily through diversified portfolios of private debt instruments. One LP allows redemption by special consent, while the other does not permit redemption. Income and capital are to be periodically distributed at the discretion of the LPs over an anticipated time frame that spans from three (2) This investment is comprised of one LP fund, which holds long and short publicly traded securities that will passively generate income. Redemptions are permitted with 30 days written notice if outside of a lock-up period. (3) This investment is comprised of interests in multiple unrelated LP funds, each structured to provide capital appreciation through diversified investments in private equity, which can include investments in buyout, venture capital, debt including senior, second lien and mezzanine, distressed debt, collateralized loan obligations and other private equity-oriented LPs. Two of the LPs allow redemption by terms set forth in the LP agreements; the others do not permit redemption. Income and capital are to be periodically distributed at the discretion of the LP over time frames that are anticipated to span up to ten years. (4) This investment is comprised of multiple unrelated LP funds. Two funds seek to obtain superior risk-adjusted absolute returns through a diversified portfolio of debt securities, including bonds, loans and other asset-backed instruments. The remaining funds focus on private middle market company mezzanine and senior secured loans, opportunities across the credit spectrum, mortgage backed-loans, as well as various types of loan-backed investments. One fund allows redemptions at any quarter-end with prior notice requirements of 180 days, while two other funds allow for redemptions with consent of the General Partner. The remaining funds do not allow redemptions. For the funds that do not allow redemptions, income and capital are to be periodically distributed at the discretion of the LP over time frames throughout the remaining life of the funds. (5) This investment is comprised of multiple unrelated LPs/LLCs funds. One fund is an LLC focused on investing in North American consumer products companies, comprised of equity and equity-related securities, as well as debt instruments. A second fund is focused on aircraft investments, along with components and assets related to aircrafts. For both funds, redemptions are not permitted. The remaining funds are real estate focused LPs, one of which allows for redemption with prior notice. ProAssurance may not sell, transfer or assign its interest in any of the above LPs/LLCs without special consent from the LPs/LLCs. Nonrecurring Fair Value Measurement ProAssurance did not have any assets or liabilities that were measured at fair value on a nonrecurring basis at June 30, 2023 or December 31, 2022. Financial Instruments - Methodologies Other Than Fair Value The following table provides the estimated fair value of the Company's financial instruments that, in accordance with GAAP for the type of investment, are measured using a methodology other than fair value. Fair values provided primarily fall within the Level 3 fair value category. June 30, 2023 December 31, 2022 (In thousands) Carrying Fair Carrying Fair Financial assets: BOLI $ 80,930 $ 80,930 $ 81,746 $ 81,746 Other investments $ 3,000 $ 3,000 $ 3,322 $ 3,322 Other assets $ 31,464 $ 31,432 $ 28,819 $ 28,790 Financial liabilities: Senior notes due 2023* $ 250,000 $ 248,463 $ 250,000 $ 248,153 Contribution Certificates $ 178,437 $ 132,515 $ 177,525 $ 134,479 Other liabilities $ 30,241 $ 30,241 $ 27,905 $ 27,905 * Carrying value excludes unamortized debt issuance costs. The fair value of the BOLI was equal to the cash surrender value associated with the policies on the valuation date. Other investments listed in the table above include FHLB common stock carried at cost and an annuity investment carried at amortized cost. Three of ProAssurance's insurance subsidiaries are members of an FHLB. The estimated fair value of the FHLB common stock was based on the amount the subsidiaries would receive if their memberships were canceled, as the memberships cannot be sold. The fair value of the annuity represents the present value of the expected future cash flows discounted using a rate available in active markets for similarly structured instruments. Other assets and other liabilities primarily consisted of related investment assets and liabilities associated with funded deferred compensation agreements. The fair value of the funded deferred compensation assets was based upon quoted market prices, which is categorized as a Level 1 valuation, and had a fair value of $30.5 million and $27.9 million at June 30, 2023 and December 31, 2022, respectively. Other assets also included an unsecured note receivable. The fair value of the note receivable was based on the present value of expected cash flows from the note receivable, discounted at market rates on the valuation date for receivables with similar credit standings and similar payment structures. Other liabilities primarily consisted of liabilities associated with funded deferred compensation agreements. The reported balance is determined based on the amount of elective deferrals and employer contributions adjusted for periodic changes in the fair value of the participant balances based on the performance of the funds selected by the participants and had a fair value of $30.2 million and $27.9 million at June 30, 2023 and December 31, 2022, respectively. The fair value of the debt, excluding the Contribution Certificates, was estimated based on the present value of expected future cash outflows, discounted at rates available on the valuation date for similar debt issued by entities with a similar credit standing to ProAssurance.

Investments

Investments	6 Months Ended
	Jun. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Available-for-sale fixed maturities at June 30, 2023 and December 31, 2022 included the following: June 30, 2023 (In thousands) Amortized Allowance for Expected Credit Losses Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available-for-sale U.S. Treasury obligations $ 251,504 $ — $ 44 $ 21,334 $ 230,214 U.S. Government-sponsored enterprise obligations 20,339 — 1 1,477 18,863 State and municipal bonds 476,863 — 351 36,983 440,231 Corporate debt 1,871,577 — 903 183,301 1,689,179 Residential mortgage-backed securities 435,406 223 485 59,117 376,551 Agency commercial mortgage-backed securities 9,733 — — 969 8,764 Other commercial mortgage-backed securities 213,545 — 35 23,568 190,012 Other asset-backed securities 420,082 196 297 21,666 398,517 $ 3,699,049 $ 419 $ 2,116 $ 348,415 $ 3,352,331 December 31, 2022 (In thousands) Amortized Allowance for Expected Credit Losses Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available-for-sale U.S. Treasury obligations $ 243,999 $ — $ 8 $ 22,399 $ 221,608 U.S. Government-sponsored enterprise obligations 21,562 — — 1,628 19,934 State and municipal bonds 483,584 — 177 44,311 439,450 Corporate debt 1,980,579 — 735 199,862 1,781,452 Residential mortgage-backed securities 450,870 229 555 61,656 389,540 Agency commercial mortgage-backed securities 10,576 — — 872 9,704 Other commercial mortgage-backed securities 217,021 — 63 22,994 194,090 Other asset-backed securities 444,220 198 289 27,617 416,694 $ 3,852,411 $ 427 $ 1,827 $ 381,339 $ 3,472,472 The recorded cost basis and estimated fair value of available-for-sale fixed maturities at June 30, 2023, by contractual maturity, are shown below. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. (In thousands) Amortized Due in one Due after Due after Due after Total Fair Fixed maturities, available-for-sale U.S. Treasury obligations $ 251,504 $ 26,685 $ 167,068 $ 33,749 $ 2,712 $ 230,214 U.S. Government-sponsored enterprise obligations 20,339 2,676 12,714 3,473 — 18,863 State and municipal bonds 476,863 33,736 149,666 148,179 108,650 440,231 Corporate debt 1,871,577 207,118 825,556 570,714 85,791 1,689,179 Residential mortgage-backed securities 435,406 376,551 Agency commercial mortgage-backed securities 9,733 8,764 Other commercial mortgage-backed securities 213,545 190,012 Other asset-backed securities 420,082 398,517 $ 3,699,049 $ 3,352,331 Excluding obligations of the U.S. Government, U.S. Government-sponsored enterprises and a U.S. Government obligations money market fund, no investment in any entity or its affiliates exceeded 10% of shareholders’ equity at June 30, 2023. Cash and securities with a carrying value of $56.7 million at June 30, 2023 were on deposit with various state insurance departments to meet regulatory requirements. ProAssurance also held securities with a carrying value of $107.8 million at June 30, 2023 that are pledged as collateral security for advances under the Company's borrowing relationships with FHLBs. As a member of Lloyd's, ProAssurance is required to maintain capital at Lloyd's, referred to as FAL, to support underwriting by Syndicate 1729. At June 30, 2023, ProAssurance's FAL investments were comprised of available-for-sale fixed maturities with a fair value of $18.7 million and cash and cash equivalents of $0.6 million on deposit with Lloyd's in order to satisfy these FAL requirements. During the second quarter of 2023, ProAssurance received a return of approximately $4.1 million of cash from its FAL balances related to the settlement of the Company's participation in the results of Syndicate 1729 and Syndicate 6121 for the 2020 underwriting year. Investments Held in a Loss Position The following tables provide summarized information with respect to investments held in an unrealized loss position at June 30, 2023 and December 31, 2022, including the length of time the investment had been held in a continuous unrealized loss position. June 30, 2023 Total Less than 12 months 12 months or longer Fair Unrealized Fair Unrealized Fair Unrealized (In thousands) Value Loss Value Loss Value Loss Fixed maturities, available-for-sale U.S. Treasury obligations $ 224,346 $ 21,334 $ 72,417 $ 5,047 $ 151,929 $ 16,287 U.S. Government-sponsored enterprise obligations 18,746 1,477 6,625 419 12,121 1,058 State and municipal bonds 411,244 36,983 103,378 4,625 307,866 32,358 Corporate debt 1,614,792 183,301 298,741 15,412 1,316,051 167,889 Residential mortgage-backed securities 341,913 59,117 92,609 9,871 249,304 49,246 Agency commercial mortgage-backed securities 8,764 969 1,822 93 6,942 876 Other commercial mortgage-backed securities 189,038 23,568 26,552 1,991 162,486 21,577 Other asset-backed securities 378,243 21,666 71,035 2,035 307,208 19,631 $ 3,187,086 $ 348,415 $ 673,179 $ 39,493 $ 2,513,907 $ 308,922 December 31, 2022 Total Less than 12 months 12 months or longer Fair Unrealized Fair Unrealized Fair Unrealized (In thousands) Value Loss Value Loss Value Loss Fixed maturities, available-for-sale U.S. Treasury obligations $ 220,991 $ 22,399 $ 53,199 $ 2,393 $ 167,792 $ 20,006 U.S. Government-sponsored enterprise obligations 19,934 1,628 8,082 663 11,852 965 State and municipal bonds 421,769 44,311 177,393 12,352 244,376 31,959 Corporate debt 1,708,529 199,862 687,947 42,977 1,020,582 156,885 Residential mortgage-backed securities 363,945 61,656 155,212 15,275 208,733 46,381 Agency commercial mortgage-backed securities 9,704 872 3,086 110 6,618 762 Other commercial mortgage-backed securities 192,359 22,994 53,270 4,087 139,089 18,907 Other asset-backed securities 396,452 27,617 162,192 7,050 234,260 20,567 $ 3,333,683 $ 381,339 $ 1,300,381 $ 84,907 $ 2,033,302 $ 296,432 As of June 30, 2023, excluding U.S. Government or U.S. Government-sponsored enterprise obligations, there were 2,781 debt securities (73.0% of all available-for-sale fixed maturity securities held) in an unrealized loss position representing 1,402 issuers. The greatest and second greatest unrealized loss positions among those securities were approximately $5.5 million and $3.6 million, respectively. The securities were evaluated for impairment as of June 30, 2023. As of December 31, 2022, excluding U.S. Government or U.S. Government-sponsored enterprise obligations, there were 2,901 debt securities (74.4% of all available-for-sale fixed maturity securities held) in an unrealized loss position representing 1,433 issuers. The greatest and second greatest unrealized loss positions among those securities were approximately $5.7 million and $4.1 million, respectively. The securities were evaluated for impairment as of December 31, 2022. Each quarter, ProAssurance performs a detailed analysis for the purpose of assessing whether any of the securities it holds in an unrealized loss position has suffered an impairment due to credit or non-credit factors. A detailed discussion of the factors considered in the assessment is included in Note 1 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K. Fixed maturity securities held in an unrealized loss position at June 30, 2023, excluding asset-backed securities, have paid all scheduled contractual payments and are expected to continue. Expected future cash flows of asset-backed securities, excluding those issued by GNMA, FNMA and FHLMC, held in an unrealized loss position were estimated as part of the June 30, 2023 impairment evaluation using the most recently available six-month historical performance data for the collateral (loans) underlying the security or, if historical data was not available, sector based assumptions, and equaled or exceeded the current amortized cost basis of the security. The following tables present a roll forward of the allowance for expected credit losses on available-for-sale fixed maturities for the three and six months ended June 30, 2023 and 2022. Three Months Ended June 30, 2023 (In thousands) Residential mortgage-backed securities Other asset-backed securities Total Balance, at April 1, 2023 $ 227 $ 197 $ 424 Reductions related to: Securities sold during the period (4) (1) (5) Balance, at June 30, 2023 $ 223 $ 196 $ 419 Six Months Ended June 30, 2023 (In thousands) Residential mortgage-backed securities Other asset-backed securities Total Balance, at December 31, 2022 $ 229 $ 198 $ 427 Reductions related to: Securities sold during the period (6) (2) (8) Balance, at June 30, 2023 $ 223 $ 196 $ 419 Three Months Ended June 30, 2022 (In thousands) Corporate Debt Total Balance, at April 1, 2022 $ — $ — Additional credit losses related to securities for which: No allowance for credit losses has been previously recognized 553 553 Balance, at June 30, 2022 $ 553 $ 553 Six Months Ended June 30, 2022 (In thousands) Corporate Debt Total Balance, at December 31, 2021 $ — $ — Reductions related to: Securities sold during the period 553 553 Balance, at June 30, 2022 $ 553 $ 553 Other information regarding sales and purchases of fixed maturity available-for-sale securities is as follows: Three Months Ended June 30 Six Months Ended June 30 (In millions) 2023 2022 2023 2022 Proceeds from sales (exclusive of maturities and paydowns) $ 19.6 $ 38.8 $ 23.4 $ 102.3 Purchases $ 65.4 $ 109.1 $ 134.2 $ 340.7 Net Investment Income Net investment income (loss) by investment category was as follows: Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Fixed maturities $ 27,951 $ 22,006 $ 55,278 $ 43,550 Equities 1,105 967 1,912 1,668 Short-term investments, including Other 4,034 727 7,384 1,153 BOLI 459 261 1,116 214 Investment fees and expenses (1,899) (2,017) (3,730) (4,198) Net investment income $ 31,650 $ 21,944 $ 61,960 $ 42,387 Investment in Unconsolidated Subsidiaries ProAssurance's investment in unconsolidated subsidiaries were as follows: June 30, 2023 Carrying Value (In thousands) Percentage June 30, December 31, Qualified affordable housing project tax credit partnerships See below $ 1,216 $ 4,088 All other investments, primarily investment fund LPs/LLCs See below 304,811 301,122 $ 306,027 $ 305,210 Qualified affordable housing project tax credit partnership interests held by ProAssurance generate investment returns by providing tax benefits to fund investors in the form of tax credits and project operating losses. The carrying value of these investments reflects ProAssurance's total commitments (both funded and unfunded) to the partnerships, less any amortization. At June 30, 2023 and December 31, 2022, ProAssurance did not have an ownership percentage greater than 20% in any tax credit partnership interests. ProAssurance's ownership percentage relative to the tax credit partnership interests is less than 20%; these interests had a carrying value of $1.2 million at June 30, 2023 and $4.1 million at December 31, 2022. Since ProAssurance has the ability to exert influence over the partnerships but does not control them, all are accounted for using the equity method. See further discussion of the entities in which ProAssurance holds passive interests in Note 10. ProAssurance holds interests in investment fund LPs/LLCs and other equity method investments and LPs/LLCs which are not considered to be investment funds. ProAssurance's ownership percentage relative to four and three of the LPs/LLCs is greater than 25% at June 30, 2023 and December 31, 2022, respectively, which is likely to be reduced as the funds mature and other investors participate in the funds; these investments had a carrying value of $46.0 million at June 30, 2023 and $36.0 million at December 31, 2022. ProAssurance's ownership percentage relative to the remaining investments and LPs/LLCs is less than 25%; these interests had a carrying value of $258.8 million at June 30, 2023 and $265.1 million at December 31, 2022. ProAssurance does not have the ability to exert control over any of these funds. Equity in Earnings (Loss) of Unconsolidated Subsidiaries Equity in earnings (loss) of unconsolidated subsidiaries included losses from qualified affordable housing project tax credit partnerships and a historic tax credit partnership. Investment results recorded reflect ProAssurance's allocable portion of partnership operating results. Tax credits reduce income tax expense in the period they are utilized. The results recorded and tax credits recognized related to ProAssurance's tax credit partnership investments were as follows: Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Qualified affordable housing project tax credit partnerships Losses recorded $ 1,511 $ 2,809 $ 1,865 $ 5,197 Tax credits recognized $ 29 $ 1,198 $ 72 $ 2,403 Historic tax credit partnership* Losses (gains) recorded $ — $ (961) $ — $ (961) *ProAssurance holds a historic tax credit partnership which was fully amortized in 2020. This partnership generated investment returns by providing benefits to partnership investors in the form of tax credits, tax deductible project operating losses and distributions resulting from positive cash flows. ProAssurance received a distribution associated with this investment during the second quarter of 2022 as a result of positive cash flows from a completed project, which was recognized as an operating gain in each respective period. For the three and six months ended June 30, 2023 the Company generated a nominal amount of tax credits from its tax credit partnership investments which were deferred for use in future periods due to the Company's expected consolidated loss calculated on a tax basis. For the three and six months ended June 30, 2022, the tax credits generated from the Company's tax credit partnership investments of $1.2 million and $2.4 million, respectively, were deferred and are expected to be utilized in future periods. Not included in the table above is $1.9 million and $2.0 million of tax credits recaptured from the 2019 tax year during the six months ended June 30, 2023 and 2022, respectively, due to the carryback of the Company's estimated NOL for both periods to the 2021 tax year. The recaptured tax credits were earned in 2019 but not utilized until 2021 due to NOL's generated in both 2019 and 2020. As of June 30, 2023, the Company had approximately $53.2 million of available tax credit carryforwards generated from its investments in tax credit partnerships which they expect to utilize in future periods. Tax credits provided by the underlying projects of the Company's historic tax credit partnership are typically available in the tax year in which the project is put into active service, whereas the tax credits provided by qualified affordable housing project tax credit partnerships are provided over approximately a ten year period. Significant Equity Method Investees As previously discussed, ProAssurance holds certain investments that are measured using the equity method of accounting, primarily investments in LPs/LLCs, which are carried as a part of investment in unconsolidated subsidiaries on the Condensed Consolidated Balance Sheets. Each quarter, ProAssurance assesses the significance of its equity method investees. As of June 30, 2023, ProAssurance determined the following method investees to be significant: • A&M Capital Opportunities Fund is a private equity fund that is focused on middle-market investments. • Harbert Seniors Housing Fund I, LP is focused on investing in seniors housing real estate. • NB CO Investment Fund II, LP is a private equity fund that is a co-investor in small and mid-cap companies. • NB Secondary Opportunities Fund III, LP is a private equity fund focused on secondary investments. • Prime Storage Fund II, LP primarily invests in self-storage real estate. • WNG Aircraft Opportunities Fund II, LP is focused on investing in aviation assets and related interests. The following table presents aggregated gross summarized financial information for the funds that ProAssurance determined to be significant as of June 30, 2023, including the portion not attributable to ProAssurance, derived from the funds' financial statements which are prepared in accordance with GAAP. As the majority of ProAssurance's equity method investments report their results to the Company on a one quarter lag, the majority of the summarized financial information below is for the six months ended March 31, 2023 and 2022. (In thousands) Six Months Ended June 30 2023 2022 Net investment income (loss) $ (11,800) $ 6,042 Net investment gains (losses) 43,369 71,001 Net change in unrealized appreciation (depreciation) 53,349 186,575 Net gain (loss) $ 84,918 $ 263,618 Net gain (loss) attributable to ProAssurance (1) $ 464 $ 4,033 (1) Represents ProAssurance's share of the funds' aggregate income or loss, which is included as a component of equity in earnings (loss) of unconsolidated subsidiaries in its Condensed Consolidated Statements of Income and Comprehensive Income for the six months ended June 30, 2023 and 2022. Net Investment Gains (Losses) Realized investment gains and losses are recognized on the first-in, first-out basis. The following table provides detailed information regarding net investment gains (losses): Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Total impairment losses: Corporate debt $ (48) $ (972) $ (2,984) $ (972) Asset-backed securities 5 — 8 — Portion of impairment losses recognized in other comprehensive income before taxes: Corporate debt — 419 — 419 Net impairment losses recognized in earnings (43) (553) (2,976) (553) Gross realized gains, available-for-sale fixed maturities 460 265 539 1,452 Gross realized (losses), available-for-sale fixed maturities (767) (965) (1,224) (2,089) Net realized gains (losses), trading fixed maturities 2 (21) (106) (97) Net realized gains (losses), equity investments 17 (5,125) 101 (5,346) Net realized gains (losses), other investments (2,115) (760) (1,886) (110) Change in unrealized holding gains (losses), trading fixed maturities 54 (455) 151 (781) Change in unrealized holding gains (losses), equity investments (1,130) (5,923) 2,616 (17,408) Change in unrealized holding gains (losses), convertible securities, carried at fair value 2,929 (10,584) 4,061 (13,059) Other (1) 3,539 237 4,582 601 Net investment gains (losses) $ 2,946 $ (23,884) $ 5,858 $ (37,390) (1) Includes gains of $2.0 million and $3.0 million recognized during the 2023 three and six months ended, respectively, reflecting the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. See further discussion on the contingent consideration in Note 2 and discussion on the Company's accounting policy in Note 1 in its December 31, 2022 report on Form 10-K. For the three and six months ended June 30, 2023, ProAssurance recognized a nominal amount and $3.0 million of credit-related impairment losses in earnings, respectively. The Company did not recognize any non-credit impairment losses in OCI during the three and six months ended June 30, 2023. The credit-related impairment losses recognized during the three and six months ended June 30, 2023 related to two corporate bonds in the financial sector. For the three and six months ended June 30, 2022, ProAssurance recognized credit-related impairment losses in earnings of $0.6 million and non-credit impairment losses in OCI of $0.4 million. The credit-related impairment losses recognized during the three and six months ended June 30, 2022 related to a corporate bond in the consumer sector. The following table presents a roll forward of cumulative losses recorded in earning related to impaired debt securities for which a portion of the impairment was recorded in OCI. Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Balance beginning of period $ 57 $ — $ 57 $ — Additional credit losses recognized during the period, related to securities for which: No impairment has been previously recognized — 553 — 553 Balance June 30 $ 57 $ 553 $ 57 $ 553

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For interim periods, ProAssurance generally utilizes the estimated annual effective tax rate method under which the Company determines its provision (benefit) for income taxes based on the current estimate of its annual effective tax rate. For the three and six months ended June 30, 2023, ProAssurance utilized the estimated annual effective tax rate method. Under the estimated annual effective tax rate method, items which are unusual, infrequent, or that cannot be reliably estimated are considered in the effective tax rate in the period in which the item is included in income and are referred to as discrete items. For the three and six months ended June 30, 2022, ProAssurance utilized the discrete effective tax rate method for recording income taxes after the estimated annual effective tax rate method produced an unreliable estimated annual effective tax rate. See further discussion on this method in Note 4 of the Notes to Condensed Consolidated Financial Statements included in ProAssurance's June 30, 2022 report on Form 10-Q. In calculating the Company's year-to-date income tax expense (benefit) under the estimated annual effective tax rate method, it includes the estimated benefit of tax credits for the year-to-date period based on the most recently available information provided by the tax credit partnerships; the actual amounts of credits provided by the tax credit partnerships may prove to be different than the Company's estimates. The effect of such a difference is recognized in the period identified. For the six months ended June 30, 2023 the provision for income taxes is different from that which would be obtained by applying the statutory federal income tax rate to income (loss) before income taxes primarily due to the estimated tax rate differential between the Company's actual effective tax rate for the six months ended June 30, 2023 and the Company's projected annual effective tax rate as of June 30, 2023 as calculated under the estimated annual effective tax rate method. The provision for income taxes for the six months ended June 30, 2023 is also different from that which would be obtained by applying the statutory federal income tax rate to income (loss) before income taxes due to the $4 million decrease in the contingent consideration liability related to the NORCAL acquisition, all of which was non-taxable. See further discussion on the contingent consideration in Note 2. ProAssurance had a liability for U.S. federal and U.K. income taxes carried as a part of other liabilities of $5.2 million as of June 30, 2023 and a receivable of $8.0 million as of December 31, 2022 carried as a part of other assets. At June 30, 2023 and December 31, 2022, the liability for unrecognized tax benefits, which is included in the total liability for U.S. federal and U.K. income taxes, was $4.1 million in each period which included an accrued liability for interest of approximately $0.5 million in each period. Coronavirus Aid, Relief and Economic Security Act

Reserve for Losses and Loss Adj

Reserve for Losses and Loss Adjustment Expenses	6 Months Ended
	Jun. 30, 2023
Insurance [Abstract]
Reserve for Losses and Loss Adjustment Expenses	Reserve for Losses and Loss Adjustment Expenses The reserve for losses is established based on estimates of individual claims and actuarially determined estimates of future losses based on ProAssurance’s past loss experience, available industry data and projections as to future claims frequency, severity, inflationary trends and settlement patterns. Estimating the reserve, particularly the reserve appropriate for liability exposures, is a complex process. For a high proportion of the risks insured or reinsured by ProAssurance, claims may be resolved over an extended period of time, often five years or more, and may be subject to litigation. Estimating losses requires ProAssurance to make and revise judgments and assessments regarding multiple uncertainties over an extended period of time. As a result, the reserve estimate may vary considerably from the eventual outcome. The assumptions used in establishing ProAssurance’s reserve are regularly reviewed and updated by management as new data becomes available. Changes to estimates of previously established reserves are included in earnings in the period in which the estimate is changed. For additional information regarding ProAssurance's reserve for losses, see Note 1 and Note 8 of the Notes to Consolidated Financial Statements included in ProAssurance's December 31, 2022 report on Form 10-K. Activity in the reserve for losses and loss adjustment expenses is summarized as follows: (In thousands) Six Months Ended June 30, 2023 Six Months Ended June 30, 2022 Year Ended December 31, 2022 Balance, beginning of year $ 3,471,147 $ 3,579,940 $ 3,579,940 Less reinsurance recoverables on unpaid losses and loss adjustment expenses 431,889 451,741 451,741 Net balance, beginning of year 3,039,258 3,128,199 3,128,199 Net losses: Current year (1) 395,632 411,397 813,515 (Favorable) unfavorable development of reserves established in prior years, net (2) 722 (24,304) (36,753) Total 396,354 387,093 776,762 Paid related to: Current year (33,129) (44,903) (108,139) Prior years (407,118) (366,643) (757,564) Total paid (440,247) (411,546) (865,703) Net balance, end of period 2,995,365 3,103,746 3,039,258 Plus reinsurance recoverables on unpaid losses and loss adjustment expenses 425,560 469,116 431,889 Balance, end of period $ 3,420,925 $ 3,572,862 $ 3,471,147 (1) Current year net losses for both the six months ended June 30, 2022 and year ended December 31, 2022 included $4.9 million of purchase accounting amortization of the negative VOBA associated with NORCAL's assumed unearned premium, which was amortized over a period in proportion to the earn-out of the associated premium as a reduction to current accident year net losses (see Note 2 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K). As of June 30, 2022, the negative VOBA was fully amortized. (2) Net prior year reserve development recognized for the six months ended June 30, 2023 and 2022 as well as the year ended December 31, 2022 included $5.0 million, $5.8 million and $10.8 million, respectively, of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses (see Note 2 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K). Estimating liability reserves is complex and requires the use of many assumptions. As time passes and ultimate losses for prior years are either known or become subject to a more precise estimation, ProAssurance increases or decreases the reserve estimates established in prior periods. The consolidated net unfavorable prior year reserve development recognized in the six months ended June 30, 2023 primarily reflected the continued challenging loss environment in Specialty P&C segment, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. During the first quarter of 2023, the Company strengthened case reserves in its Specialty P&C segment related to four large claims resulting in net unfavorable prior year reserve development of $10.1 million recognized during the six months ended June 30, 2023, $7.5 million of which related to NORCAL's accident years 2016 and 2020. The net unfavorable prior year reserve development recognized in the Specialty P&C segment was partially offset by approximately $4.0 million of favorable prior year reserve development due to lower than anticipated loss emergence in the Company's Medical Technology Liability line of business, principally related to accident years 2014 through 2017. The consolidated net unfavorable loss development also reflected unfavorable development recognized during the first quarter of 2023 in the Workers' Compensation Insurance segment primarily attributable to one large claim from the 1997 accident year. The unfavorable reserve development recognized in the Lloyd's Syndicates segment was driven by higher than expected loss development on certain large claims, primarily catastrophe related losses. Consolidated net unfavorable loss development recognized in the six months ended June 30, 2023 was partially offset by favorable reserve development recognized in the Segregated Portfolio Cell Reinsurance segment driven by overall favorable trends in claim closing patterns primarily in accident years 2018 through 2021. The net favorable loss development recognized in the six months ended June 30, 2022 primarily reflected a lower than anticipated loss emergence in the Specialty P&C segment, primarily related to the 2018 through 2021 accident years. The net favorable development recognized in the Specialty P&C segment also included a $3.0 million reduction in the Company's prior accident year IBNR reserve for COVID-19 during the second quarter of 2022 as early first notices of potential claims related to anticipated COVID losses have not turned into claims. The favorable development also reflected overall favorable trends in claim closing patterns in the Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments. The net favorable loss development recognized in the Workers' Compensation Insurance segment is primarily related to the 2017 accident year and prior. The net favorable loss development recognized in the Segregated Portfolio Cell Reinsurance segment is primarily related to the 2019 and 2020 accident years. Net favorable development recognized during the six months ended June 30, 2022 was net of an increase to the Company's reserve for potential ECO/XPL claims of $4.0 million in the Specialty P&C segment. Consolidated net favorable loss development recognized in the six months ended June 30, 2022 was partially offset by unfavorable reserve development recognized in the Lloyd's Syndicates segment driven by certain catastrophe related losses. As of June 30, 2022, ProAssurance did not recognize any development related to NORCAL's accident years 2020 or prior since the date of acquisition on May 5, 2021. The net favorable loss development recognized for the year ended December 31, 2022 primarily reflected a lower than anticipated loss emergence in the Specialty P&C segment related to the 2017, 2020 and 2021 accident years, primarily attributable to NORCAL's 2021 accident year, and, to a lesser extent, the Medical Technology Liability line of business. The net favorable development recognized in the Specialty P&C segment also included a $9.0 million reduction in the Company's prior accident year IBNR reserve for COVID-19 as early first notices of potential claims related to anticipated COVID losses have not turned into claims. Further, the net favorable development recognized in the Specialty P&C segment was partially offset by higher than anticipated loss severity trends in select jurisdictions in the HCPL line of business, which emerged primarily in the fourth quarter of 2022. As of December 31, 2022, ProAssurance did not recognize any development related to NORCAL's accident years 2020 or prior since the date of acquisition on May 5, 2021. The net favorable development also reflected overall favorable trends in claim closing patterns in the Workers' Compensation Insurance and Segregated Portfolio Cell Reinsurance segments. The net favorable loss development recognized in the Workers' Compensation Insurance segment is primarily related to the 2017 through 2020 accident years. The net favorable loss development recognized in the Segregated Portfolio Cell Reinsurance segment is primarily related to the 2016 through 2021 accident years. Consolidated net favorable loss development recognized in 2022 was partially offset by unfavorable reserve development recognized in the Lloyd's Syndicates segment driven by higher than expected loss development on certain large claims, primarily catastrophe related losses.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies ProAssurance is involved in various legal actions related to insurance policies and claims handling including, but not limited to, claims asserted by policyholders. These types of legal actions arise in the Company's ordinary course of business and, in accordance with GAAP for insurance entities, are considered as a part of the Company's loss reserving process, which is described in detail under the heading "Losses and Loss Adjustment Expenses" in the Accounting Policies section in Note 1 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K. ProAssurance also has other direct actions against the Company unrelated to its claims activity which are evaluated and accounted for as a part of other liabilities. For these corporate legal actions, the Company evaluates each case separately and establishes what it believes is an appropriate reserve based on GAAP guidance related to contingent liabilities. As of June 30, 2023, there were no material reserves established for corporate legal actions. As a member of Lloyd's, ProAssurance has obligations to Syndicate 1729 including a Syndicate Credit Agreement and FAL requirements. The Syndicate Credit Agreement was an unconditional revolving credit agreement to the Premium Trust Fund of Syndicate 1729 for the purpose of providing working capital. The Syndicate Credit Agreement had a maturity date of June 30, 2023 and contained an annual auto-renewal feature which allowed for ProAssurance to elect to non-renew if notice is given at least 30 days prior to the next auto-renewal date, which is one year prior to the maturity date. On May 23, 2022, ProAssurance provided such notice of termination of the Syndicate Credit Agreements. As a result, the Syndicate Credit Agreements expired on June 30, 2023. ProAssurance provides FAL to support underwriting by Syndicate 1729 which is comprised of investment securities and cash and cash equivalents deposited with Lloyd's with a total fair value of approximately $19.3 million at June 30, 2023 (see Note 3). During the second quarter of 2023, the Company received a return of approximately $4.1 million of cash from its FAL balances related to the settlement of its participation in the results of Syndicate 1729 and Syndicate 6131 for the 2020 underwriting year. ProAssurance has entered into financial instrument transactions that may present off-balance sheet credit risk or market risk. These transactions include a short-term loan commitment and commitments to provide funding to non-public investment entities. Under the short-term loan commitment, ProAssurance has agreed to advance funds on a 30 day basis to a counterparty provided there is no violation of any condition established in the contract. As of June 30, 2023, ProAssurance had total funding commitments related to non-public investment entities as well as the short-term loan commitment of approximately $178.5 million which included the amount at risk if the full short-term loan is extended and the counterparties default. However, the credit risk associated with the short-term loan commitment is minimal as the counterparties to the contract are highly rated commercial institutions and to-date have been performing in accordance with their contractual obligations. As such, ProAssurance’s expected credit losses associated with this short-term loan commitment were nominal in amount as of June 30, 2023. ProAssurance entered into a services agreement with a company to provide data analytics services for certain product lines within the Company's HCPL book of business. Under the services agreement, the Company has committed to an annual fee of approximately $3.5 million for three years. In addition, the services agreement contains an annual one-year auto-extension feature, in November, unless either party elects to non-renew the services agreement by providing notice at least six-months prior to the end of the contract. ProAssurance incurred operating expenses associated with this services agreement of $0.8 million and $1.7 million for the three and six months ended June 30, 2023, respectively, as compared to $0.9 million and $1.8 million for the same respective periods of 2022. As of June 30, 2023, the remaining commitment under this agreement was estimated to be approximately $4.6 million.

Debt

Debt	6 Months Ended
	Jun. 30, 2023
Debt Disclosure [Abstract]
Debt	Debt ProAssurance’s outstanding debt consisted of the following: ($ in thousands) June 30, December 31, Senior Notes due 2023, unsecured, interest at 5.3% annually $ 250,000 $ 250,000 Contribution Certificates due 2031, interest at 3.0% (effective interest rate at 4.35%) paid annually in April 178,437 177,525 Total principal 428,437 427,525 Less unamortized debt issuance costs 2,411 542 Debt less unamortized debt issuance costs $ 426,026 $ 426,983 Revolving Credit Agreement and Term Loan On April 28, 2023, ProAssurance executed an amendment to the Revolving Credit Agreement, which extended the expiration from November 2024 to April 2028 and includes a $125 million delayed draw term loan ("Term Loan"). The Term Loan is available to be drawn during a five year period after closing, subject to customary borrowing conditions. The Company intends to draw on the amended Revolving Credit Agreement, including the Term Loan, to refinance its Senior Notes that mature November 2023 (see additional information on the Company's Senior Notes in Note 11 of the Notes to Consolidated Financial Statements included in ProAssurance's December 31, 2022 report on Form 10-K). The amended Revolving Credit Agreement may be used for general corporate purposes, including, but not limited to, short-term working capital, share repurchases as authorized by the Board and support for other activities. ProAssurance's amended Revolving Credit Agreement permits borrowings up to $250 million, and has available a $50 million accordion feature which, if successfully subscribed, would expand the permitted borrowings to a maximum of $300 million. As of June 30, 2023 and December 31, 2022, there were no outstanding borrowings on the Revolving Credit Agreement. The amended Revolving Credit Agreement permits ProAssurance to borrow, repay and reborrow from the lenders during the term of the amended Revolving Credit Agreement. All borrowings are required to be repaid prior to the expiration date of the amended Revolving Credit Agreement. ProAssurance is required to pay a commitment fee, ranging from 0.20% to 0.45% based on ProAssurance’s debt to capitalization ratio, on the average unused portion of the amended Revolving Credit Agreement during the term of the agreement. Borrowings under the agreements may be secured or unsecured and accrue interest at a selected base rate, adjusted by a margin, which can vary from 0% to 2.375%, based on ProAssurance’s debt to capitalization ratio and whether the borrowing is secured or unsecured. The base rate selected may either be the current one-, three- or six-month SOFR, with the SOFR term selected fixing the interest period for which the rate is effective. If no selection is made, the base rate defaults to the highest of (1) Zero, (2) the Prime rate, (3) the Federal Funds rate plus 0.5% or (4) the one-month SOFR Adjusted Screen Rate plus 1.0%, determined daily. Rates are reset each successive interest period until the borrowing is repaid. The amended Revolving Credit Agreement contains customary representations, covenants and events constituting default, and remedies for default. Additionally, the agreement carries the following financial covenants: (1) ProAssurance is not permitted to have a leverage ratio of consolidated funded indebtedness (principally, obligations for borrowed money, obligations evidenced by instruments such as notes or acceptances, standby and commercial letters of credit, and contingent obligations) to consolidated total capitalization (principally, total non-trade liabilities on a consolidated basis plus consolidated shareholders’ equity, exclusive of AOCI) greater than 0.35 to 1.0, determined at the end of each fiscal quarter. (2) ProAssurance is required to maintain a minimum net worth, excluding AOCI, of at least $912 million. (3) ProAssurance is required to maintain minimum liquidity, which will include cash, securities, and capacity on its revolving line, of at least $25 million. As of June 30, 2023, ProAssurance is in compliance with all covenants of the amended Revolving Credit Agreement. Covenant Compliance There are no financial covenants associated with the Senior Notes or the Contribution Certificates due 2023 and 2031, respectively. The amended Revolving Credit Agreement contains customary representations, covenants and events constituting default, and remedies for default, as previously discussed. As of June 30, 2023, ProAssurance is in compliance with all covenants of the amended Revolving Credit Agreement. Additional Information For additional information regarding ProAssurance's debt, see Note 11 of the Notes to Consolidated Financial Statements included in ProAssurance's December 31, 2022 report on Form 10-K.

Derivatives

Derivatives	6 Months Ended
	Jun. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives ProAssurance is exposed to certain risks relating to its ongoing business and investment activities. ProAssurance utilizes derivative instruments as part of its risk management strategy to reduce the market risk related to fluctuations in future interest rates associated with a portion of its variable-rate debt. See Note 1 for the Company's accounting policy regarding derivative instruments. To manage the Company's exposure to variability in cash flows of forecasted interest payments attributable to variability in the selected base rates on borrowings under both the amended Revolving Credit Agreement and Term Loan, ProAssurance entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps") on May 2, 2023, each with an effective date of December 29, 2023 and a maturity date of March 31, 2028. ProAssurance's Interest Rate Swaps are designated and qualify as highly effective cash flow hedges, consequently, changes in the fair value of the Interest Rate Swaps are recorded in AOCI, net of tax, and are reclassified into earnings when the hedged cash flows impact earnings. The Interest Rate Swap hedging the variability in cash flows associated with interest payments on the amended Revolving Credit Agreement will have a constant $125 million notional amount throughout the term of the swap, while the Interest Rate Swap hedging the variability in cash flows associated with interest payments on the Term Loan will have an amortizing $125 million notional amount, which is designed to match the outstanding principal on the Term Loan throughout the term of the swap. Borrowings under the amended Revolving Credit Agreement and Term Loan will accrue interest at a selected base rate, adjusted by a margin. The Interest Rate Swaps effectively fix the base rate on borrowings under the amended Revolving Credit Agreement and Term Loan to 3.187% and 3.207%, respectively. The margin component of the interest rate, which can vary from 0% to 2.375%, will remain variable and is based on ProAssurance’s debt to capitalization ratio. Additional information regarding the Company's amended Revolving Credit Agreement and Term Loan is provided in Note 7. ProAssurance received cash collateral from the counterparty to secure the net present value of future cash flows associated with the Interest Rate Swaps of $5.5 million and is reflected as a component of other liabilities on the Condensed Consolidated Balance Sheets as of June 30, 2023. The following table provides a summary of the volume and fair value position of the Interest Rate Swaps as well as the reporting location in the Condensed Consolidated Balance Sheets as of June 30, 2023. ($ in thousands) June 30, 2023 Derivatives Designated and Qualifying as Cash Flow Hedging Instruments Location in the Condensed Consolidated Balance Sheets Number of Instruments Aggregate Notional Amount (1) Estimated Fair Value (2) Interest Rate Swaps Other Assets 2 $250,000 $5,455 (1) Volume is represented by the derivative instruments' notional amount. (2) Additional information regarding the fair value of the Company's Interest Rate Swaps is provided in Note 2. For the three and six months ended June 30, 2023, ProAssurance did not reclassify any gain or loss on the Interest Rate Swaps from AOCI into earnings. At June 30, 2023, management estimates that it will reclassify approximately $2.4 million of pre-tax net gains on the Interest Rate Swaps from AOCI to earnings over the next twelve months, beginning on the effective date of the Interest Rate Swaps, which will be recorded to interest expense. See additional information on gains or losses related to the Interest Rate Swaps reported as a component of AOCI in Note 9.

Shareholders' Equity

Shareholders' Equity	6 Months Ended
	Jun. 30, 2023
Equity [Abstract]
Shareholders' Equity	Shareholders’ Equity At June 30, 2023 and December 31, 2022, ProAssurance had 100 million shares of authorized common stock and 50 million shares of authorized preferred stock. The Board has the authority to determine provisions for the issuance of preferred shares, including the number of shares to be issued, the designations, powers, preferences and rights, and the qualifications, limitations or restrictions of such shares. ProAssurance declared cash dividends of $0.05 per share during the first quarter of 2023 and each of the first two quarters of 2022, totaling $2.7 million and $5.4 million, respectively. In light of the price range in which the Company's stock traded in the second quarter of 2023, the Board decided to suspend payment of a quarterly cash dividend. Instead, the Company used available capital to repurchase shares pursuant to the existing share repurchase authorization. Any decision to pay future cash dividends is subject to the Board’s final determination after a comprehensive review of financial performance, future expectations and other factors deemed relevant by the Board. See Note 12 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K for additional information. At June 30, 2023, Board authorizations for the repurchase of common shares or the retirement of outstanding debt of $86.4 million remained available for use. ProAssurance repurchased approximately 1.4 million common shares at a cost of $20.0 million during the second quarter of 2023. ProAssurance did not repurchase any common shares during the six months ended June 30, 2022. Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) The following tables provide a detailed breakout of the components of AOCI and the amounts reclassified from AOCI to net income (loss). The tax effects of all amounts in the tables below, except for an immaterial amount of unrealized gains and losses on available-for-sale securities held at the Company's U.K. subsidiary, were computed using the enacted U.S. federal corporate tax rate of 21%. OCI included a deferred tax benefit of $2.7 million and a deferred tax expense of $8.1 million for the three and six months ended June 30, 2023, respectively, and a deferred tax benefit of $29.6 million and $67.8 million for the same respective periods of 2022. The changes in the balance of each component of AOCI for the three and six months ended June 30, 2023 and 2022 were as follows: (In thousands) Unrealized Investment Gains (Losses) on Securities Cash Flow Hedging Gains (Losses) (1) Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance April 1, 2023 $ (254,513) $ — $ (11) $ (1,454) $ (255,978) OCI, before reclassifications, net of tax (16,074) 4,310 — — (11,764) Amounts reclassified from AOCI, net of tax 262 — — — 262 Net OCI, current period (15,812) 4,310 — — (11,502) Balance at June 30, 2023 $ (270,325) $ 4,310 $ (11) $ (1,454) $ (267,480) (In thousands) Unrealized Investment Gains (Losses) on Securities Cash Flow Hedging Gains (Losses) (1) Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance, December 31, 2022 $ (297,142) $ — $ (11) $ (1,454) $ (298,607) OCI, before reclassifications, net of tax 23,933 4,310 — — 28,243 Amounts reclassified from AOCI, net of tax 2,884 — — — 2,884 Net OCI, current period 26,817 4,310 — — 31,127 Balance, June 30, 2023 $ (270,325) $ 4,310 $ (11) $ (1,454) $ (267,480) (In thousands) Unrealized Investment Gains (Losses) on Securities Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance April 1, 2022 $ (125,907) $ — $ 1,341 $ (124,566) OCI, before reclassifications, net of tax (110,191) (331) — (110,522) Amounts reclassified from AOCI, net of tax 1,053 — (153) 900 Net OCI, current period (109,138) (331) (153) (109,622) Balance at June 30, 2022 $ (235,045) $ (331) $ 1,188 $ (234,188) (In thousands) Unrealized Investment Gains (Losses) on Securities Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance, December 31, 2021 $ 14,929 $ — $ 1,355 $ 16,284 OCI, before reclassifications, net of tax (250,999) (331) — (251,330) Amounts reclassified from AOCI, net of tax 1,025 — (167) 858 Net OCI, current period (249,974) (331) (167) (250,472) Balance, June 30, 2022 $ (235,045) $ (331) $ 1,188 $ (234,188)

Variable Interest Entities

Variable Interest Entities	6 Months Ended
	Jun. 30, 2023
Variable Interest Entities [Abstract]
Variable Interest Entities	Variable Interest Entities ProAssurance holds passive interests in a number of entities that are considered to be VIEs under GAAP guidance. ProAssurance's VIE interests principally consist of interests in LPs/LLCs formed for the purpose of achieving diversified equity and debt returns. ProAssurance's VIE interests, carried as a part of investment in unconsolidated subsidiaries, totaled $277.6 million at June 30, 2023 and $277.5 million at December 31, 2022. ProAssurance does not have power over the activities that most significantly impact the economic performance of these VIEs and thus is not the primary beneficiary. Investments in entities where ProAssurance holds a greater than minor interest but does not hold a controlling interest are accounted for using the equity method. Therefore, ProAssurance has not consolidated these VIEs. ProAssurance’s involvement with each of these VIEs is limited to its direct ownership interest in the VIE. Except for the funding commitments disclosed in Note 6, ProAssurance has no arrangements with any of these VIEs to provide other financial support to or on behalf of the VIE. At June 30, 2023, ProAssurance’s maximum loss exposure relative to these investments was limited to the carrying value of ProAssurance’s investment in the VIE. ProAssurance is the primary beneficiary of PPM RRG. While there is no direct ownership of PPM RRG by ProAssurance, it manages the business operations of PPM RRG through its management services agreement and has effective control of the PPM RRG's Board of Directors through an irrevocable voting proxy. The management services agreement allows ProAssurance to provide management and oversight services to the RRG, which includes the ability to make business decisions impacting the operations of PPM RRG. PPM RRG has a $5 million surplus note to NORCAL which is its only source of capital. At June 30, 2023 and December 31, 2022, approximately $134 million and $154 million of ProAssurance's assets, respectively, and approximately $134 million and $154 million of its liabilities, respectively, included on the Condensed Consolidated Balance Sheet were related to PPM RRG.

Earnings (Loss) Per Share

Earnings (Loss) Per Share	6 Months Ended
	Jun. 30, 2023
Earnings Per Share [Abstract]
Earnings (Loss) Per Share	Earnings (Loss) Per Share Diluted weighted average shares is calculated as basic weighted average shares plus the effect, calculated using the treasury stock method, of assuming that restricted share units and performance share units have vested. The following table provides a reconciliation between the Company's basic weighted average number of common shares outstanding to its diluted weighted average number of common shares outstanding: (In thousands, except per share data) Three Months Ended Six Months Ended 2023 2022 2023 2022 Weighted average number of common shares outstanding, basic 53,815 54,068 53,900 54,040 Dilutive effect of securities: Restricted Share Units 87 104 95 109 Performance Share Units 16 14 22 16 Weighted average number of common shares outstanding, diluted 53,918 54,186 54,017 54,165 Effect of dilutive shares on earnings (loss) per share $ — $ — $ — $ — The diluted weighted average number of common shares outstanding for the three and six months ended June 30, 2023 excluded approximately 339,000 and 170,000, respectively, of common share equivalents issuable under the Company's stock compensation plans, as compared to approximately 4,000 and 2,000 during the same respective periods of 2022, as their effect would have been antidilutive.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2023
Segment Reporting [Abstract]
Segment Information	Segment Information ProAssurance's segments are based on the Company's internal management reporting structure for which financial results are regularly evaluated by the Company's CODM to determine resource allocation and assess operating performance. The Company continually assesses its internal management reporting structure and information evaluated by its CODM to determine whether any changes have occurred that would impact its segment reporting structure. The Company operates in five segments that are organized around the nature of the products and services provided: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance, Lloyd's Syndicates and Corporate. Additional information regarding ProAssurance's segments is included in Note 16 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K. A description of each of ProAssurance's five operating and reportable segments follows. • Specialty P&C includes professional liability insurance and medical technology liability insurance. • Workers' Compensation Insurance includes workers' compensation insurance products which are provided primarily to employers with 1,000 or fewer employees. • Segregated Portfolio Cell Reinsurance includes the results (underwriting profit or loss, plus investment results, net of U.S. federal income taxes) of SPCs at Inova Re and Eastern Re, the Company's Cayman Islands SPC operations. • Lloyd's Syndicates includes the results from ProAssurance's participation in Lloyd's of London Syndicate 1729 and Syndicate 6131. ProAssurance's participation in the results of Syndicate 1729 for the 2023 underwriting year remains unchanged from the 2022 underwriting year at 5% and the Company ceased participation in Syndicate 6131 beginning with the 2022 underwriting year. Due to the quarter lag, the Company's ceased participation in Syndicate 6131 was not reflected in its results until the second quarter of 2022. • Corporate includes ProAssurance's investment operations excluding those reported in the Company's Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments. In addition, this segment includes corporate expenses, interest expense, U.S. income taxes and non-premium revenues generated outside of the Company's insurance entities. The accounting policies of the segments are described in Note 1 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K. ProAssurance evaluates the performance of its Specialty P&C and Workers' Compensation Insurance segments based on before tax underwriting profit or loss. ProAssurance evaluates the performance of its Segregated Portfolio Cell Reinsurance segment based on operating profit or loss, which includes investment results of investment assets solely allocated to SPC operations, net of U.S. federal income taxes. Performance of the Lloyd's Syndicates segment is evaluated based on operating profit or loss, which includes investment results of investment assets solely allocated to Lloyd's Syndicate operations, net of U.K. income tax expense. Performance of the Corporate segment is evaluated based on the contribution made to consolidated after-tax results. ProAssurance accounts for inter-segment transactions as if the transactions were to third parties at current market prices. Assets are not allocated to segments because investments, other than the investments discussed above that are solely allocated to the Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments, and other assets are not managed at the segment level. The tabular information that follows shows the financial results of the Company's reportable segments reconciled to results reflected in the Condensed Consolidated Statements of Income and Comprehensive Income. ProAssurance does not consider changes in the fair value of contingent consideration or transaction-related costs for completed business combinations, including any related tax impacts, in assessing the financial performance of its operating and reportable segments, and thus are included in the reconciliation of segment results to consolidated results. Financial results by segment were as follows: Three Months Ended June 30, 2023 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 178,902 $ 41,018 $ 24,094 $ 3,848 $ — $ — $ 247,862 Net investment income — — 603 137 30,910 — 31,650 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 6,632 — 6,632 Net investment gains (losses) — — 1,194 33 (281) — 946 Other income (expense) (1) 1,021 651 1 5 2,173 (1,110) 2,741 Net losses and loss adjustment expenses (145,044) (29,762) (13,816) (2,436) — — (191,058) Underwriting, policy acquisition and operating expenses (1) (47,439) (14,400) (6,538) (1,434) (8,275) 1,110 (76,976) SPC U.S. federal income tax expense (2) — — (994) — — — (994) SPC dividend (expense) income — — (3,747) — — — (3,747) Interest expense — — — — (5,502) — (5,502) Income tax benefit (expense) — — — — (2,927) — (2,927) Segment results $ (12,560) $ (2,493) $ 797 $ 153 $ 22,730 $ — 8,627 Reconciliation of segments to consolidated results: Contingent Consideration Adjustment (3) 2,000 Net income (loss) $ 10,627 Significant non-cash items: Depreciation and amortization, net of accretion $ 2,559 $ 854 $ (552) $ 2 $ 3,091 $ — $ 5,954 Six Months Ended June 30, 2023 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 358,245 $ 81,821 $ 39,394 $ 8,189 $ — $ — $ 487,649 Net investment income — — 1,024 325 60,611 — 61,960 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 5,511 — 5,511 Net investment gains (losses) — — 2,355 22 481 — 2,858 Other income (expense) (1) 2,014 1,232 1 2 2,500 (2,221) 3,528 Net losses and loss adjustment expenses (309,096) (60,606) (22,238) (4,414) — — (396,354) Underwriting, policy acquisition and operating expenses (1) (88,399) (27,379) (11,575) (3,155) (16,477) 2,221 (144,764) SPC U.S. federal income tax expense (2) — — (1,526) — — — (1,526) SPC dividend (expense) income — — (5,689) — — — (5,689) Interest expense — — — — (10,965) — (10,965) Income tax benefit (expense) — — — — (755) — (755) Segment results $ (37,236) $ (4,932) $ 1,746 $ 969 $ 40,906 $ — 1,453 Reconciliation of segments to consolidated results: Contingent Consideration Adjustment (3) 3,000 Net income (loss) $ 4,453 Significant non-cash items: Depreciation and amortization, net of accretion $ 5,199 $ 1,723 $ (488) $ 3 $ 7,194 $ — $ 13,631 Three Months Ended June 30, 2022 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 183,547 $ 41,709 $ 16,222 $ 5,793 $ — $ — $ 247,271 Net investment income — — 211 143 21,590 — 21,944 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 5,180 — 5,180 Net investment gains (losses) — — (2,782) (485) (20,617) — (23,884) Other income (expense) (1) 1,903 517 1 129 3,626 (862) 5,314 Net losses and loss adjustment expenses (137,002) (27,947) (9,272) (3,449) — — (177,670) Underwriting, policy acquisition and operating expenses (1) (48,077) (13,669) (5,237) (1,508) (9,019) 862 (76,648) SPC U.S. federal income tax expense (2) — — (349) — — — (349) SPC dividend (expense) income — — 854 — — — 854 Interest expense — — — — (4,919) — (4,919) Income tax benefit (expense) — — — — 1,789 — 1,789 Segment results $ 371 $ 610 $ (352) $ 623 $ (2,370) $ — (1,118) Reconciliation of segments to consolidated results: Transaction-related costs, net (4) (541) Net income (loss) $ (1,659) Significant non-cash items: Depreciation and amortization, net of accretion $ 2,948 $ 874 $ 345 $ 10 $ 5,882 $ — $ 10,059 Six Months Ended June 30, 2022 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 381,514 $ 82,393 $ 35,536 $ 13,539 $ — $ — $ 512,982 Net investment income — — 323 355 41,709 — 42,387 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 12,799 — 12,799 Net investment gains (losses) — — (3,493) (884) (33,013) — (37,390) Other income (expense) (1) 2,924 1,199 1 263 5,691 (1,959) 8,119 Net losses and loss adjustment expenses (302,960) (55,158) (20,763) (8,212) — — (387,093) Underwriting, policy acquisition and operating expenses (1) (90,958) (26,669) (9,605) (4,218) (17,756) 1,959 (147,247) SPC U.S. federal income tax expense (2) — — (991) — — — (991) SPC dividend (expense) income — — (1,513) — — — (1,513) Interest expense — — — — (9,360) — (9,360) Income tax benefit (expense) — — — — 3,559 — 3,559 Segment results $ (9,480) $ 1,765 $ (505) $ 843 $ 3,629 $ — (3,748) Reconciliation of segments to consolidated results: Transaction-related costs (4) (1,471) Net income (loss) $ (5,219) Significant non-cash items: Depreciation and amortization, net of accretion $ 5,540 $ 1,748 $ 715 $ 24 $ 12,382 $ — $ 20,409 (1) Includes certain fees for services provided by the Workers' Compensation Insurance segment to the SPCs at Inova Re and Eastern Re which are recorded as expenses within the Segregated Portfolio Cell Reinsurance segment and as other income within the Workers' Compensation Insurance segment. These fees are primarily SPC rental fees and are eliminated between segments in consolidation. (2) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs. (3) Represents the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition included as a component of consolidated net investment gains (losses) on the Condensed Consolidated Statements of Income and Comprehensive Income. See further discussion on the contingent consideration in Note 2. (4) Represents the transaction-related costs, after-tax, associated with the acquisition of NORCAL. For the three and six months ended June 30, 2022 pre-tax transaction-related costs of approximately $0.7 million and $1.9 million, respectively, were included as a component of consolidated operating expense and the associated income tax benefit of approximately $0.2 million and $0.4 million, respectively, were included as a component of consolidated income tax benefit (expense) on the Condensed Consolidated Statements of Income and Comprehensive Income. The following table provides detailed information regarding ProAssurance's gross premiums earned by product as well as a reconciliation to net premiums earned. All gross premiums earned are from external customers except as noted. ProAssurance's insured risks are primarily within the U.S. Three Months Ended June 30 Six Months Ended June 30 (In thousands) 2023 2022 2023 2022 Specialty P&C Segment Gross premiums earned: HCPL $ 168,928 $ 165,496 $ 331,315 $ 341,043 Small Business Unit 25,931 26,188 52,005 52,726 Medical Technology Liability 10,610 9,968 21,156 19,968 Other — 203 — 397 Ceded premiums earned (26,567) (18,308) (46,231) (32,620) Segment net premiums earned 178,902 183,547 358,245 381,514 Workers' Compensation Insurance Segment Gross premiums earned: Traditional business 44,660 45,395 88,200 88,551 Alternative market business 17,484 18,126 35,110 36,004 Ceded premiums earned (21,126) (21,812) (41,489) (42,162) Segment net premiums earned 41,018 41,709 81,821 82,393 Segregated Portfolio Cell Reinsurance Segment Gross premiums earned: Workers' compensation (1) 16,329 17,092 32,633 34,270 HCPL (2) 10,061 1,504 11,360 5,990 Ceded premiums earned (2,296) (2,374) (4,599) (4,724) Segment net premiums earned 24,094 16,222 39,394 35,536 Lloyd's Syndicates Segment Gross premiums earned: Property and casualty 4,522 6,443 9,568 15,675 Ceded premiums earned (674) (650) (1,379) (2,136) Segment net premiums earned 3,848 5,793 8,189 13,539 Consolidated net premiums earned $ 247,862 $ 247,271 $ 487,649 $ 512,982 (1) Premium for all periods is assumed from the Workers' Compensation Insurance segment. (2) Premium for all periods is assumed from the Specialty P&C segment.

Benefit Plans

Benefit Plans	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Benefit Plans	Benefit Plans ProAssurance sponsors a defined benefit pension plan which covers substantially all NORCAL employees (except those that were previous employees of Medicus Insurance Company and FD Insurance Company, employees of PPM RRG as well as new hires after December 31, 2013). Benefits are based on years of service and the employee’s average of the highest five years of annual compensation. Annual contributions to the defined benefit pension plan are above the minimum funding standards outlined in the Employee Retirement Income Security Act of 1974, as amended. ProAssurance makes contributions to the defined benefit pension plan with the goal of ensuring that it is adequately funded to meet its future obligations. ProAssurance did not make any contributions to the pension plan during the three and six months ended June 30, 2023 and does not anticipate making any contributions for the remainder of 2023. The defined benefit pension plan no longer has future service accruals or compensation increases because this plan was frozen effective December 31, 2015. See Note 17 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K for more information regarding the defined benefit pension plan. The components of the net periodic benefit cost (income) for the three and six months ended June 30, 2023 and 2022 were as follows: ($ in thousands) Three Months Ended Six Months Ended 2023 2022 2023 2022 Components of net periodic benefit cost (income): Interest cost $ 914 $ 720 $ 1,818 $ 1,431 Expected return on Plan assets (884) (1,001) (1,758) (1,990) Total net periodic benefit cost (income)* $ 30 $ (281) $ 60 $ (559) *Net periodic benefit cost (income) is included as a component of operating expense on the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2023 and 2022.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Pay vs Performance Disclosure
Net income (loss)	$ 10,627	$ (1,659)	$ 4,453	$ (5,219)

Insider Trading Arrangements

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

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of PresentationThe accompanying unaudited Condensed Consolidated Financial Statements include the accounts of ProAssurance Corporation, its wholly owned subsidiaries and VIEs in which ProAssurance is the primary beneficiary (ProAssurance, PRA or the Company). See Note 10 for more information on ProAssurance's VIE interests. The financial statements have been prepared in accordance with GAAP for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation, consisting of normal recurring adjustments, have been included. ProAssurance’s results for the six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The accompanying Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and Notes contained in ProAssurance’s December 31, 2022 report on Form 10-K. ProAssurance operates in five reportable segments as follows: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance, Lloyd's Syndicates and Corporate.
Accounting Policies	Accounting Policies The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, revenues and expenses, and disclosures related to these amounts at the date of the financial statements. The Company evaluates these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that the Company believes to be reasonable under the circumstances. The Company can make no assurance that actual results will conform to its estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions. Other than as disclosed below, the significant accounting policies followed by ProAssurance in making estimates that materially affect financial reporting are summarized in Note 1 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K. Derivatives ProAssurance records derivative instruments at fair value in the Condensed Consolidated Balance Sheets. ProAssurance accounts for the changes in fair value of derivatives depending on whether the derivative is designated as a hedging instrument and if so, the type of hedging relationship. For derivative instruments not designated as hedging instruments, ProAssurance recognizes the change in fair value of the derivative in earnings during the period of change. ProAssurance does not use derivative instruments for trading purposes. For derivative financial instruments designed as cash flow hedges, ProAssurance formally documents all relationships between the hedging instruments and the hedged items as well as its risk-management objective and strategy for undertaking various hedged transactions. ProAssurance also formally assesses, both at the hedge's inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in cash flows of hedged items. When it is determined that a derivative is not highly effective as a hedge or that it has ceased to be a highly effective hedge, ProAssurance discontinues hedge accounting prospectively. As of June 30, 2023, ProAssurance uses Interest Rate Swaps that are designated and qualify as highly effective cash flow hedges to manage its exposure to variability in cash flows of forecasted interest payments attributable to variability in the selected base rates on borrowings under the amended Revolving Credit Agreement. Changes in the fair value of derivatives that are designated and qualify as highly effective cash flow hedges are recorded in AOCI, net of tax, and are reclassified into earnings when the hedged cash flows impact earnings. When the change in the fair value of a qualifying cash flow hedge is included in earnings, it is included in the same line item on the Condensed Consolidated Statement of Income and Comprehensive Income as the cash flows from the hedged item. The Company has elected not to offset fair value amounts recognized for the Interest Rate Swaps and fair value of the amounts recognized to reclaim cash collateral or the obligation to return cash collateral executed with counterparties under a master netting arrangement. The cash flows of derivatives used in hedging relationships are classified as either operating, investing, or financing cash flows based on the classification of the hedged item.
Accounting Changes Adopted and Not Yet Adopted	Accounting Changes Adopted Reference Rate Reform - Deferral of LIBOR Sunset Date (ASU 2022-06) Effective for fiscal years beginning after December 31, 2022 and interim periods within those fiscal years, the FASB amended guidance which defers the LIBOR transition date from December 31, 2022 to December 31, 2024. ProAssurance has exposure to LIBOR in its available-for-sale fixed maturities portfolio which represented approximately 1% of total investments, or $60 million as of June 30, 2023; 73% of these investments with exposure to LIBOR were issued since 2020 and include provisions for an alternative benchmark rate. ProAssurance adopted the guidance beginning January 1, 2023, and adoption had no material effect on ProAssurance's results of operations, financial position or cash flows. Presentation of Financial Statements, Income Statement—Reporting Comprehensive Income, Distinguishing Liabilities from Equity, Equity and Compensation—Stock Compensation (ASU 2023-03) Effective immediately, the FASB amended guidance on July 14, 2023 to align various SEC paragraphs in the Codification to reflect the issuance of SEC Staff Accounting Bulletin No. 120, among other things. ProAssurance adopted the guidance beginning July 14, 2023, and adoption had no material effect on ProAssurance's results of operations, financial position or cash flows. Accounting Changes Not Yet Adopted ProAssurance is not aware of any accounting changes not yet adopted as of June 30, 2023 that could have a material impact on its results of operations, financial position or cash flows.
Employee Retention Credit	Employee Retention Credit In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations, including the initial version of the ERC. In December 2020 and March 2021, the ERC was extended and expanded from 50% of qualified wages to 70%. The 2020 rules limited qualified wages to $10,000 per employee and applied to employers with 100 or fewer full-time employees in 2019. The rules were expanded in 2021 to raise the qualified wage limit to $10,000 per employee, per quarter. As an eligible employer, NORCAL filed a claim during the second quarter of 2023 for a payroll tax refund of approximately $3.8 million. The Company recorded the expected payroll tax refund as a component of operating expenses on the Condensed Consolidated Statements of Income and Comprehensive Income for the six months ended June 30, 2023 and as a component of other assets on the Condensed Consolidated Balance Sheets as of June 30, 2023.

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	6 Months Ended
	Jun. 30, 2023
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets	Fair values of assets measured at fair value on a recurring basis as of June 30, 2023 and December 31, 2022 are shown in the following tables. Where applicable, the tables also indicate the fair value hierarchy of the valuation techniques utilized to determine those fair values. For some assets, the inputs used to measure fair value may fall into different levels of the fair value hierarchy. When this is the case, the asset is categorized based on the level of the most significant input to the fair value measurement. Assessments of the significance of a particular input to the fair value measurement require judgment and consideration of factors specific to the assets being valued. For more information on the valuation methodologies used regarding securities in the Level 2 and Level 3 categories, see Note 3 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2022 report on Form 10-K. June 30, 2023 Fair Value Measurements Using Total (In thousands) Level 1 Level 2 Level 3 Fair Value Assets: Fixed maturities, available-for-sale U.S. Treasury obligations $ — $ 230,214 $ — $ 230,214 U.S. Government-sponsored enterprise obligations — 18,863 — 18,863 State and municipal bonds — 440,231 — 440,231 Corporate debt, multiple observable inputs — 1,621,785 — 1,621,785 Corporate debt, limited observable inputs — — 67,394 67,394 Residential mortgage-backed securities — 376,263 288 376,551 Agency commercial mortgage-backed securities — 8,764 — 8,764 Other commercial mortgage-backed securities — 190,012 — 190,012 Other asset-backed securities — 397,576 941 398,517 Fixed maturities, trading — 45,732 — 45,732 Equity investments Financial 9,884 2,219 288 12,391 Utilities/Energy 892 — — 892 Industrial — — 4,946 4,946 Bond funds 113,164 — — 113,164 All other 18,136 — — 18,136 Short-term investments 205,896 109,685 — 315,581 Other investments 1,106 60,681 500 62,287 Other assets — 5,455 — 5,455 Total assets categorized within the fair value hierarchy $ 349,078 $ 3,507,480 $ 74,357 3,930,915 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Investment in unconsolidated subsidiaries 270,495 Total assets at fair value $ 4,201,410 Liabilities: Other liabilities $ 5,450 $ — $ 11,000 $ 16,450 Total liabilities categorized within the fair value hierarchy $ 5,450 $ — $ 11,000 $ 16,450 December 31, 2022 Fair Value Measurements Using Total (In thousands) Level 1 Level 2 Level 3 Fair Value Assets: Fixed maturities, available-for-sale U.S. Treasury obligations $ — $ 221,608 $ — $ 221,608 U.S. Government-sponsored enterprise obligations — 19,934 — 19,934 State and municipal bonds — 439,450 — 439,450 Corporate debt, multiple observable inputs — 1,717,479 — 1,717,479 Corporate debt, limited observable inputs — — 63,973 63,973 Residential mortgage-backed securities — 389,291 249 389,540 Agency commercial mortgage-backed securities — 9,704 — 9,704 Other commercial mortgage-backed securities — 194,090 — 194,090 Other asset-backed securities — 413,989 2,705 416,694 Fixed maturities, trading — 43,434 — 43,434 Equity investments Financial 9,850 2,219 303 12,372 Utilities/Energy 854 — — 854 Industrial — — 2,500 2,500 Bond funds 112,136 — — 112,136 All other 15,876 — — 15,876 Short-term investments 181,937 63,376 — 245,313 Other investments 1,881 88,783 1,783 92,447 Total assets categorized within the fair value hierarchy $ 322,534 $ 3,603,357 $ 71,513 3,997,404 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Investment in unconsolidated subsidiaries 262,485 Total assets at fair value $ 4,259,889 Liabilities: Other liabilities $ — $ — $ 15,000 $ 15,000 Total liabilities categorized within the fair value hierarchy $ — $ — $ 15,000 $ 15,000
Schedule of Quantitative Information Regarding Level 3 Valuations	Quantitative Information Regarding Level 3 Valuations Below is a quantitative information regarding securities in the Level 3 category, by security type: Fair Value at ($ in thousands) June 30, 2023 December 31, 2022 Valuation Technique Unobservable Input Range Assets: Corporate debt, limited observable inputs $67,394 $63,973 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Residential mortgage-backed securities $288 $249 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other asset-backed securities $941 $2,705 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Equity investments $5,234 $2,803 Discounted Cash Flows Comparability Adjustment 0% - 10% (5%) Other investments $500 $1,783 Discounted Cash Flows Comparability Adjustment 0% - 10% (5%) Liabilities: Other liabilities $11,000 $15,000 Stochastic Model/Discounted Cash Flows Weighted Average Cost of Capital 0% - 10% (9%)
Schedule of Fair Value Measurements - Level 3 Assets	The following tables present summary information regarding changes in the fair value of assets and liabilities measured using Level 3 inputs. June 30, 2023 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Other Liabilities Total Liabilities Balance, March 31, 2023 $ 76,157 $ 5,054 $ 2,800 $ 500 $ 84,511 $ (13,000) $ (13,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (loss) (23) — — — (23) — — Net investment gains (losses) (3) — (737) — (740) 2,000 2,000 Included in other comprehensive income (loss) (142) (13) — — (155) — — Purchases 4,084 — 3,171 — 7,255 — — Sales (3,595) (396) — — (3,991) — — Transfers out (9,084) (3,416) — — (12,500) — — Balance, June 30, 2023 $ 67,394 $ 1,229 $ 5,234 $ 500 $ 74,357 $ (11,000) $ (11,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ (737) $ — $ (737) $ — $ — June 30, 2023 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Assets Other Liabilities Total Liabilities Balance, December 31, 2022 $ 63,973 $ 2,954 $ 2,803 $ 1,783 $ 71,513 $ (15,000) $ (15,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (loss) (23) — — — (23) — — Net investment gains (losses) 13 — (740) — (727) 3,000 3,000 Operating expense — — — — — 1,000 1,000 Included in other comprehensive income (loss) 67 26 — — 93 — — Purchases 10,406 1,863 3,171 — 15,440 — — Sales (4,027) (396) — — (4,423) — — Transfers in 11,220 1,779 — — 12,999 — — Transfers out (14,235) (4,997) — (1,283) (20,515) — — Balance, June 30, 2023 $ 67,394 $ 1,229 $ 5,234 $ 500 $ 74,357 $ (11,000) $ (11,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ (740) $ — $ (740) $ — $ — June 30, 2022 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Other Liabilities Total Liabilities Balance, March 31, 2022 $ 53,325 $ 9,303 $ 2,500 $ 3,440 $ 68,568 $ (24,000) $ (24,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment gains (losses) — — — (787) (787) — — Included in other comprehensive income (loss) (1,319) (177) — — (1,496) — — Purchases 8,787 1,473 — — 10,260 — — Sales (2,007) (192) — — (2,199) — — Transfers in 17,828 570 2,125 — 20,523 — — Transfers out (2,402) (6,939) — (1,752) (11,093) — — Balance, June 30, 2022 $ 74,212 $ 4,038 $ 4,625 $ 901 $ 83,776 $ (24,000) $ (24,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ — $ (787) $ (787) $ — $ — June 30, 2022 Level 3 Fair Value Measurements Assets Liabilities (In thousands) Corporate Debt Asset-backed Securities Equity Investments Other Investments Total Assets Other Liabilities Total Liabilities Balance, December 31, 2021 $ 47,129 $ 6,502 $ 2,500 $ 1,434 $ 57,565 $ (24,000) $ (24,000) Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (loss) — 1 — — 1 — — Net investment gains (losses) — — — (677) (677) — — Included in other comprehensive income (loss) (2,312) (437) — — (2,749) — — Purchases 18,498 7,058 — 1,483 27,039 — — Sales (3,026) (197) — (116) (3,339) — — Transfers in 18,828 570 2,125 529 22,052 — — Transfers out (4,905) (9,459) — (1,752) (16,116) — — Balance, June 30, 2022 $ 74,212 $ 4,038 $ 4,625 $ 901 $ 83,776 $ (24,000) $ (24,000) Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end $ — $ — $ — $ (723) $ (723) $ — $ —
Schedule of Investments in LLCs and Limited Partnerships	The amount of ProAssurance's unfunded commitments related to these investments as of June 30, 2023 and fair values of these investments as of June 30, 2023 and December 31, 2022 were as follows: Unfunded Fair Value (In thousands) June 30, June 30, December 31, Investment in unconsolidated subsidiaries: Private debt funds (1) $1,885 $ 19,970 $ 19,620 Long/short equity funds (2) None 4,876 5,089 Non-public equity funds (3) $51,582 144,908 144,560 Credit funds (4) $31,251 50,178 49,245 Strategy focused funds (5) $9,016 50,563 43,971 Total investments carried at NAV $ 270,495 $ 262,485 Below is additional information regarding each of the investments listed in the table above as of June 30, 2023. (1) This investment is comprised of interests in two unrelated LP funds that are structured to provide interest distributions primarily through diversified portfolios of private debt instruments. One LP allows redemption by special consent, while the other does not permit redemption. Income and capital are to be periodically distributed at the discretion of the LPs over an anticipated time frame that spans from three (2) This investment is comprised of one LP fund, which holds long and short publicly traded securities that will passively generate income. Redemptions are permitted with 30 days written notice if outside of a lock-up period. (3) This investment is comprised of interests in multiple unrelated LP funds, each structured to provide capital appreciation through diversified investments in private equity, which can include investments in buyout, venture capital, debt including senior, second lien and mezzanine, distressed debt, collateralized loan obligations and other private equity-oriented LPs. Two of the LPs allow redemption by terms set forth in the LP agreements; the others do not permit redemption. Income and capital are to be periodically distributed at the discretion of the LP over time frames that are anticipated to span up to ten years. (4) This investment is comprised of multiple unrelated LP funds. Two funds seek to obtain superior risk-adjusted absolute returns through a diversified portfolio of debt securities, including bonds, loans and other asset-backed instruments. The remaining funds focus on private middle market company mezzanine and senior secured loans, opportunities across the credit spectrum, mortgage backed-loans, as well as various types of loan-backed investments. One fund allows redemptions at any quarter-end with prior notice requirements of 180 days, while two other funds allow for redemptions with consent of the General Partner. The remaining funds do not allow redemptions. For the funds that do not allow redemptions, income and capital are to be periodically distributed at the discretion of the LP over time frames throughout the remaining life of the funds. (5) This investment is comprised of multiple unrelated LPs/LLCs funds. One fund is an LLC focused on investing in North American consumer products companies, comprised of equity and equity-related securities, as well as debt instruments. A second fund is focused on aircraft investments, along with components and assets related to aircrafts. For both funds, redemptions are not permitted. The remaining funds are real estate focused LPs, one of which allows for redemption with prior notice.
Schedule of Financial Instruments Not Measured at Fair Value	The following table provides the estimated fair value of the Company's financial instruments that, in accordance with GAAP for the type of investment, are measured using a methodology other than fair value. Fair values provided primarily fall within the Level 3 fair value category. June 30, 2023 December 31, 2022 (In thousands) Carrying Fair Carrying Fair Financial assets: BOLI $ 80,930 $ 80,930 $ 81,746 $ 81,746 Other investments $ 3,000 $ 3,000 $ 3,322 $ 3,322 Other assets $ 31,464 $ 31,432 $ 28,819 $ 28,790 Financial liabilities: Senior notes due 2023* $ 250,000 $ 248,463 $ 250,000 $ 248,153 Contribution Certificates $ 178,437 $ 132,515 $ 177,525 $ 134,479 Other liabilities $ 30,241 $ 30,241 $ 27,905 $ 27,905 * Carrying value excludes unamortized debt issuance costs.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-For-Sale Fixed Maturities	Available-for-sale fixed maturities at June 30, 2023 and December 31, 2022 included the following: June 30, 2023 (In thousands) Amortized Allowance for Expected Credit Losses Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available-for-sale U.S. Treasury obligations $ 251,504 $ — $ 44 $ 21,334 $ 230,214 U.S. Government-sponsored enterprise obligations 20,339 — 1 1,477 18,863 State and municipal bonds 476,863 — 351 36,983 440,231 Corporate debt 1,871,577 — 903 183,301 1,689,179 Residential mortgage-backed securities 435,406 223 485 59,117 376,551 Agency commercial mortgage-backed securities 9,733 — — 969 8,764 Other commercial mortgage-backed securities 213,545 — 35 23,568 190,012 Other asset-backed securities 420,082 196 297 21,666 398,517 $ 3,699,049 $ 419 $ 2,116 $ 348,415 $ 3,352,331 December 31, 2022 (In thousands) Amortized Allowance for Expected Credit Losses Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available-for-sale U.S. Treasury obligations $ 243,999 $ — $ 8 $ 22,399 $ 221,608 U.S. Government-sponsored enterprise obligations 21,562 — — 1,628 19,934 State and municipal bonds 483,584 — 177 44,311 439,450 Corporate debt 1,980,579 — 735 199,862 1,781,452 Residential mortgage-backed securities 450,870 229 555 61,656 389,540 Agency commercial mortgage-backed securities 10,576 — — 872 9,704 Other commercial mortgage-backed securities 217,021 — 63 22,994 194,090 Other asset-backed securities 444,220 198 289 27,617 416,694 $ 3,852,411 $ 427 $ 1,827 $ 381,339 $ 3,472,472
Schedule of Available-For-Sale Securities by Contractual Maturity	The recorded cost basis and estimated fair value of available-for-sale fixed maturities at June 30, 2023, by contractual maturity, are shown below. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. (In thousands) Amortized Due in one Due after Due after Due after Total Fair Fixed maturities, available-for-sale U.S. Treasury obligations $ 251,504 $ 26,685 $ 167,068 $ 33,749 $ 2,712 $ 230,214 U.S. Government-sponsored enterprise obligations 20,339 2,676 12,714 3,473 — 18,863 State and municipal bonds 476,863 33,736 149,666 148,179 108,650 440,231 Corporate debt 1,871,577 207,118 825,556 570,714 85,791 1,689,179 Residential mortgage-backed securities 435,406 376,551 Agency commercial mortgage-backed securities 9,733 8,764 Other commercial mortgage-backed securities 213,545 190,012 Other asset-backed securities 420,082 398,517 $ 3,699,049 $ 3,352,331
Schedule of Investments Held in an Unrealized Loss Position	The following tables provide summarized information with respect to investments held in an unrealized loss position at June 30, 2023 and December 31, 2022, including the length of time the investment had been held in a continuous unrealized loss position. June 30, 2023 Total Less than 12 months 12 months or longer Fair Unrealized Fair Unrealized Fair Unrealized (In thousands) Value Loss Value Loss Value Loss Fixed maturities, available-for-sale U.S. Treasury obligations $ 224,346 $ 21,334 $ 72,417 $ 5,047 $ 151,929 $ 16,287 U.S. Government-sponsored enterprise obligations 18,746 1,477 6,625 419 12,121 1,058 State and municipal bonds 411,244 36,983 103,378 4,625 307,866 32,358 Corporate debt 1,614,792 183,301 298,741 15,412 1,316,051 167,889 Residential mortgage-backed securities 341,913 59,117 92,609 9,871 249,304 49,246 Agency commercial mortgage-backed securities 8,764 969 1,822 93 6,942 876 Other commercial mortgage-backed securities 189,038 23,568 26,552 1,991 162,486 21,577 Other asset-backed securities 378,243 21,666 71,035 2,035 307,208 19,631 $ 3,187,086 $ 348,415 $ 673,179 $ 39,493 $ 2,513,907 $ 308,922 December 31, 2022 Total Less than 12 months 12 months or longer Fair Unrealized Fair Unrealized Fair Unrealized (In thousands) Value Loss Value Loss Value Loss Fixed maturities, available-for-sale U.S. Treasury obligations $ 220,991 $ 22,399 $ 53,199 $ 2,393 $ 167,792 $ 20,006 U.S. Government-sponsored enterprise obligations 19,934 1,628 8,082 663 11,852 965 State and municipal bonds 421,769 44,311 177,393 12,352 244,376 31,959 Corporate debt 1,708,529 199,862 687,947 42,977 1,020,582 156,885 Residential mortgage-backed securities 363,945 61,656 155,212 15,275 208,733 46,381 Agency commercial mortgage-backed securities 9,704 872 3,086 110 6,618 762 Other commercial mortgage-backed securities 192,359 22,994 53,270 4,087 139,089 18,907 Other asset-backed securities 396,452 27,617 162,192 7,050 234,260 20,567 $ 3,333,683 $ 381,339 $ 1,300,381 $ 84,907 $ 2,033,302 $ 296,432
Schedule of a Roll Forward of Cumulative Credit Losses Recorded in Earnings Related to Impaired Debt Securities	The following tables present a roll forward of the allowance for expected credit losses on available-for-sale fixed maturities for the three and six months ended June 30, 2023 and 2022. Three Months Ended June 30, 2023 (In thousands) Residential mortgage-backed securities Other asset-backed securities Total Balance, at April 1, 2023 $ 227 $ 197 $ 424 Reductions related to: Securities sold during the period (4) (1) (5) Balance, at June 30, 2023 $ 223 $ 196 $ 419 Six Months Ended June 30, 2023 (In thousands) Residential mortgage-backed securities Other asset-backed securities Total Balance, at December 31, 2022 $ 229 $ 198 $ 427 Reductions related to: Securities sold during the period (6) (2) (8) Balance, at June 30, 2023 $ 223 $ 196 $ 419 Three Months Ended June 30, 2022 (In thousands) Corporate Debt Total Balance, at April 1, 2022 $ — $ — Additional credit losses related to securities for which: No allowance for credit losses has been previously recognized 553 553 Balance, at June 30, 2022 $ 553 $ 553 Six Months Ended June 30, 2022 (In thousands) Corporate Debt Total Balance, at December 31, 2021 $ — $ — Reductions related to: Securities sold during the period 553 553 Balance, at June 30, 2022 $ 553 $ 553 The following table presents a roll forward of cumulative losses recorded in earning related to impaired debt securities for which a portion of the impairment was recorded in OCI. Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Balance beginning of period $ 57 $ — $ 57 $ — Additional credit losses recognized during the period, related to securities for which: No impairment has been previously recognized — 553 — 553 Balance June 30 $ 57 $ 553 $ 57 $ 553
Schedule of Other Information Regarding Available-For-Sale Securities	Other information regarding sales and purchases of fixed maturity available-for-sale securities is as follows: Three Months Ended June 30 Six Months Ended June 30 (In millions) 2023 2022 2023 2022 Proceeds from sales (exclusive of maturities and paydowns) $ 19.6 $ 38.8 $ 23.4 $ 102.3 Purchases $ 65.4 $ 109.1 $ 134.2 $ 340.7
Schedule of Net Investment Income	Net investment income (loss) by investment category was as follows: Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Fixed maturities $ 27,951 $ 22,006 $ 55,278 $ 43,550 Equities 1,105 967 1,912 1,668 Short-term investments, including Other 4,034 727 7,384 1,153 BOLI 459 261 1,116 214 Investment fees and expenses (1,899) (2,017) (3,730) (4,198) Net investment income $ 31,650 $ 21,944 $ 61,960 $ 42,387
Schedule of Investment in Unconsolidated Subsidiaries	ProAssurance's investment in unconsolidated subsidiaries were as follows: June 30, 2023 Carrying Value (In thousands) Percentage June 30, December 31, Qualified affordable housing project tax credit partnerships See below $ 1,216 $ 4,088 All other investments, primarily investment fund LPs/LLCs See below 304,811 301,122 $ 306,027 $ 305,210
Schedule of Equity Method Investments	The results recorded and tax credits recognized related to ProAssurance's tax credit partnership investments were as follows: Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Qualified affordable housing project tax credit partnerships Losses recorded $ 1,511 $ 2,809 $ 1,865 $ 5,197 Tax credits recognized $ 29 $ 1,198 $ 72 $ 2,403 Historic tax credit partnership* Losses (gains) recorded $ — $ (961) $ — $ (961) *ProAssurance holds a historic tax credit partnership which was fully amortized in 2020. This partnership generated investment returns by providing benefits to partnership investors in the form of tax credits, tax deductible project operating losses and distributions resulting from positive cash flows. ProAssurance received a distribution associated with this investment during the second quarter of 2022 as a result of positive cash flows from a completed project, which was recognized as an operating gain in each respective period. The following table presents aggregated gross summarized financial information for the funds that ProAssurance determined to be significant as of June 30, 2023, including the portion not attributable to ProAssurance, derived from the funds' financial statements which are prepared in accordance with GAAP. As the majority of ProAssurance's equity method investments report their results to the Company on a one quarter lag, the majority of the summarized financial information below is for the six months ended March 31, 2023 and 2022. (In thousands) Six Months Ended June 30 2023 2022 Net investment income (loss) $ (11,800) $ 6,042 Net investment gains (losses) 43,369 71,001 Net change in unrealized appreciation (depreciation) 53,349 186,575 Net gain (loss) $ 84,918 $ 263,618 Net gain (loss) attributable to ProAssurance (1) $ 464 $ 4,033 (1) Represents ProAssurance's share of the funds' aggregate income or loss, which is included as a component of equity in earnings (loss) of unconsolidated subsidiaries in its Condensed Consolidated Statements of Income and Comprehensive Income for the six months ended June 30, 2023 and 2022.
Schedule of Net Realized Investment Gains (Losses)	Realized investment gains and losses are recognized on the first-in, first-out basis. The following table provides detailed information regarding net investment gains (losses): Three Months Ended Six Months Ended (In thousands) 2023 2022 2023 2022 Total impairment losses: Corporate debt $ (48) $ (972) $ (2,984) $ (972) Asset-backed securities 5 — 8 — Portion of impairment losses recognized in other comprehensive income before taxes: Corporate debt — 419 — 419 Net impairment losses recognized in earnings (43) (553) (2,976) (553) Gross realized gains, available-for-sale fixed maturities 460 265 539 1,452 Gross realized (losses), available-for-sale fixed maturities (767) (965) (1,224) (2,089) Net realized gains (losses), trading fixed maturities 2 (21) (106) (97) Net realized gains (losses), equity investments 17 (5,125) 101 (5,346) Net realized gains (losses), other investments (2,115) (760) (1,886) (110) Change in unrealized holding gains (losses), trading fixed maturities 54 (455) 151 (781) Change in unrealized holding gains (losses), equity investments (1,130) (5,923) 2,616 (17,408) Change in unrealized holding gains (losses), convertible securities, carried at fair value 2,929 (10,584) 4,061 (13,059) Other (1) 3,539 237 4,582 601 Net investment gains (losses) $ 2,946 $ (23,884) $ 5,858 $ (37,390) (1) Includes gains of $2.0 million and $3.0 million recognized during the 2023 three and six months ended, respectively, reflecting the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. See further discussion on the contingent consideration in Note 2 and discussion on the Company's accounting policy in Note 1 in its December 31, 2022 report on Form 10-K.

Reserve for Losses and Loss A_2

Reserve for Losses and Loss Adjustment Expenses (Tables)	6 Months Ended
	Jun. 30, 2023
Insurance [Abstract]
Schedule of Reserve for Losses and Loss Adjustment Expenses	Activity in the reserve for losses and loss adjustment expenses is summarized as follows: (In thousands) Six Months Ended June 30, 2023 Six Months Ended June 30, 2022 Year Ended December 31, 2022 Balance, beginning of year $ 3,471,147 $ 3,579,940 $ 3,579,940 Less reinsurance recoverables on unpaid losses and loss adjustment expenses 431,889 451,741 451,741 Net balance, beginning of year 3,039,258 3,128,199 3,128,199 Net losses: Current year (1) 395,632 411,397 813,515 (Favorable) unfavorable development of reserves established in prior years, net (2) 722 (24,304) (36,753) Total 396,354 387,093 776,762 Paid related to: Current year (33,129) (44,903) (108,139) Prior years (407,118) (366,643) (757,564) Total paid (440,247) (411,546) (865,703) Net balance, end of period 2,995,365 3,103,746 3,039,258 Plus reinsurance recoverables on unpaid losses and loss adjustment expenses 425,560 469,116 431,889 Balance, end of period $ 3,420,925 $ 3,572,862 $ 3,471,147 (1) Current year net losses for both the six months ended June 30, 2022 and year ended December 31, 2022 included $4.9 million of purchase accounting amortization of the negative VOBA associated with NORCAL's assumed unearned premium, which was amortized over a period in proportion to the earn-out of the associated premium as a reduction to current accident year net losses (see Note 2 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K). As of June 30, 2022, the negative VOBA was fully amortized. (2) Net prior year reserve development recognized for the six months ended June 30, 2023 and 2022 as well as the year ended December 31, 2022 included $5.0 million, $5.8 million and $10.8 million, respectively, of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses (see Note 2 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2022 report on Form 10-K).

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2023
Debt Disclosure [Abstract]
Schedule of Outstanding Debt	ProAssurance’s outstanding debt consisted of the following: ($ in thousands) June 30, December 31, Senior Notes due 2023, unsecured, interest at 5.3% annually $ 250,000 $ 250,000 Contribution Certificates due 2031, interest at 3.0% (effective interest rate at 4.35%) paid annually in April 178,437 177,525 Total principal 428,437 427,525 Less unamortized debt issuance costs 2,411 542 Debt less unamortized debt issuance costs $ 426,026 $ 426,983

Derivatives (Tables)

Derivatives (Tables)	6 Months Ended
	Jun. 30, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of interest rate caps	The following table provides a summary of the volume and fair value position of the Interest Rate Swaps as well as the reporting location in the Condensed Consolidated Balance Sheets as of June 30, 2023. ($ in thousands) June 30, 2023 Derivatives Designated and Qualifying as Cash Flow Hedging Instruments Location in the Condensed Consolidated Balance Sheets Number of Instruments Aggregate Notional Amount (1) Estimated Fair Value (2) Interest Rate Swaps Other Assets 2 $250,000 $5,455 (1) Volume is represented by the derivative instruments' notional amount. (2) Additional information regarding the fair value of the Company's Interest Rate Swaps is provided in Note 2.

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2023
Equity [Abstract]
Schedule of Components of AOCI, Net of Tax	The changes in the balance of each component of AOCI for the three and six months ended June 30, 2023 and 2022 were as follows: (In thousands) Unrealized Investment Gains (Losses) on Securities Cash Flow Hedging Gains (Losses) (1) Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance April 1, 2023 $ (254,513) $ — $ (11) $ (1,454) $ (255,978) OCI, before reclassifications, net of tax (16,074) 4,310 — — (11,764) Amounts reclassified from AOCI, net of tax 262 — — — 262 Net OCI, current period (15,812) 4,310 — — (11,502) Balance at June 30, 2023 $ (270,325) $ 4,310 $ (11) $ (1,454) $ (267,480) (In thousands) Unrealized Investment Gains (Losses) on Securities Cash Flow Hedging Gains (Losses) (1) Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance, December 31, 2022 $ (297,142) $ — $ (11) $ (1,454) $ (298,607) OCI, before reclassifications, net of tax 23,933 4,310 — — 28,243 Amounts reclassified from AOCI, net of tax 2,884 — — — 2,884 Net OCI, current period 26,817 4,310 — — 31,127 Balance, June 30, 2023 $ (270,325) $ 4,310 $ (11) $ (1,454) $ (267,480) (In thousands) Unrealized Investment Gains (Losses) on Securities Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance April 1, 2022 $ (125,907) $ — $ 1,341 $ (124,566) OCI, before reclassifications, net of tax (110,191) (331) — (110,522) Amounts reclassified from AOCI, net of tax 1,053 — (153) 900 Net OCI, current period (109,138) (331) (153) (109,622) Balance at June 30, 2022 $ (235,045) $ (331) $ 1,188 $ (234,188) (In thousands) Unrealized Investment Gains (Losses) on Securities Non-credit Impairments Unrecognized Change in Defined Benefit Plan Liabilities Accumulated Other Comprehensive Income (Loss) Balance, December 31, 2021 $ 14,929 $ — $ 1,355 $ 16,284 OCI, before reclassifications, net of tax (250,999) (331) — (251,330) Amounts reclassified from AOCI, net of tax 1,025 — (167) 858 Net OCI, current period (249,974) (331) (167) (250,472) Balance, June 30, 2022 $ (235,045) $ (331) $ 1,188 $ (234,188) (1) ProAssurance entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps") on May 2, 2023, each of which are designated and qualify as a cash flow hedge. See Note 8 for additional information on the Interest Rate Swaps.

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	6 Months Ended
	Jun. 30, 2023
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table provides a reconciliation between the Company's basic weighted average number of common shares outstanding to its diluted weighted average number of common shares outstanding: (In thousands, except per share data) Three Months Ended Six Months Ended 2023 2022 2023 2022 Weighted average number of common shares outstanding, basic 53,815 54,068 53,900 54,040 Dilutive effect of securities: Restricted Share Units 87 104 95 109 Performance Share Units 16 14 22 16 Weighted average number of common shares outstanding, diluted 53,918 54,186 54,017 54,165 Effect of dilutive shares on earnings (loss) per share $ — $ — $ — $ —

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2023
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The tabular information that follows shows the financial results of the Company's reportable segments reconciled to results reflected in the Condensed Consolidated Statements of Income and Comprehensive Income. ProAssurance does not consider changes in the fair value of contingent consideration or transaction-related costs for completed business combinations, including any related tax impacts, in assessing the financial performance of its operating and reportable segments, and thus are included in the reconciliation of segment results to consolidated results. Financial results by segment were as follows: Three Months Ended June 30, 2023 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 178,902 $ 41,018 $ 24,094 $ 3,848 $ — $ — $ 247,862 Net investment income — — 603 137 30,910 — 31,650 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 6,632 — 6,632 Net investment gains (losses) — — 1,194 33 (281) — 946 Other income (expense) (1) 1,021 651 1 5 2,173 (1,110) 2,741 Net losses and loss adjustment expenses (145,044) (29,762) (13,816) (2,436) — — (191,058) Underwriting, policy acquisition and operating expenses (1) (47,439) (14,400) (6,538) (1,434) (8,275) 1,110 (76,976) SPC U.S. federal income tax expense (2) — — (994) — — — (994) SPC dividend (expense) income — — (3,747) — — — (3,747) Interest expense — — — — (5,502) — (5,502) Income tax benefit (expense) — — — — (2,927) — (2,927) Segment results $ (12,560) $ (2,493) $ 797 $ 153 $ 22,730 $ — 8,627 Reconciliation of segments to consolidated results: Contingent Consideration Adjustment (3) 2,000 Net income (loss) $ 10,627 Significant non-cash items: Depreciation and amortization, net of accretion $ 2,559 $ 854 $ (552) $ 2 $ 3,091 $ — $ 5,954 Six Months Ended June 30, 2023 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 358,245 $ 81,821 $ 39,394 $ 8,189 $ — $ — $ 487,649 Net investment income — — 1,024 325 60,611 — 61,960 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 5,511 — 5,511 Net investment gains (losses) — — 2,355 22 481 — 2,858 Other income (expense) (1) 2,014 1,232 1 2 2,500 (2,221) 3,528 Net losses and loss adjustment expenses (309,096) (60,606) (22,238) (4,414) — — (396,354) Underwriting, policy acquisition and operating expenses (1) (88,399) (27,379) (11,575) (3,155) (16,477) 2,221 (144,764) SPC U.S. federal income tax expense (2) — — (1,526) — — — (1,526) SPC dividend (expense) income — — (5,689) — — — (5,689) Interest expense — — — — (10,965) — (10,965) Income tax benefit (expense) — — — — (755) — (755) Segment results $ (37,236) $ (4,932) $ 1,746 $ 969 $ 40,906 $ — 1,453 Reconciliation of segments to consolidated results: Contingent Consideration Adjustment (3) 3,000 Net income (loss) $ 4,453 Significant non-cash items: Depreciation and amortization, net of accretion $ 5,199 $ 1,723 $ (488) $ 3 $ 7,194 $ — $ 13,631 Three Months Ended June 30, 2022 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 183,547 $ 41,709 $ 16,222 $ 5,793 $ — $ — $ 247,271 Net investment income — — 211 143 21,590 — 21,944 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 5,180 — 5,180 Net investment gains (losses) — — (2,782) (485) (20,617) — (23,884) Other income (expense) (1) 1,903 517 1 129 3,626 (862) 5,314 Net losses and loss adjustment expenses (137,002) (27,947) (9,272) (3,449) — — (177,670) Underwriting, policy acquisition and operating expenses (1) (48,077) (13,669) (5,237) (1,508) (9,019) 862 (76,648) SPC U.S. federal income tax expense (2) — — (349) — — — (349) SPC dividend (expense) income — — 854 — — — 854 Interest expense — — — — (4,919) — (4,919) Income tax benefit (expense) — — — — 1,789 — 1,789 Segment results $ 371 $ 610 $ (352) $ 623 $ (2,370) $ — (1,118) Reconciliation of segments to consolidated results: Transaction-related costs, net (4) (541) Net income (loss) $ (1,659) Significant non-cash items: Depreciation and amortization, net of accretion $ 2,948 $ 874 $ 345 $ 10 $ 5,882 $ — $ 10,059 Six Months Ended June 30, 2022 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 381,514 $ 82,393 $ 35,536 $ 13,539 $ — $ — $ 512,982 Net investment income — — 323 355 41,709 — 42,387 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 12,799 — 12,799 Net investment gains (losses) — — (3,493) (884) (33,013) — (37,390) Other income (expense) (1) 2,924 1,199 1 263 5,691 (1,959) 8,119 Net losses and loss adjustment expenses (302,960) (55,158) (20,763) (8,212) — — (387,093) Underwriting, policy acquisition and operating expenses (1) (90,958) (26,669) (9,605) (4,218) (17,756) 1,959 (147,247) SPC U.S. federal income tax expense (2) — — (991) — — — (991) SPC dividend (expense) income — — (1,513) — — — (1,513) Interest expense — — — — (9,360) — (9,360) Income tax benefit (expense) — — — — 3,559 — 3,559 Segment results $ (9,480) $ 1,765 $ (505) $ 843 $ 3,629 $ — (3,748) Reconciliation of segments to consolidated results: Transaction-related costs (4) (1,471) Net income (loss) $ (5,219) Significant non-cash items: Depreciation and amortization, net of accretion $ 5,540 $ 1,748 $ 715 $ 24 $ 12,382 $ — $ 20,409 (1) Includes certain fees for services provided by the Workers' Compensation Insurance segment to the SPCs at Inova Re and Eastern Re which are recorded as expenses within the Segregated Portfolio Cell Reinsurance segment and as other income within the Workers' Compensation Insurance segment. These fees are primarily SPC rental fees and are eliminated between segments in consolidation. (2) Represents the provision for U.S. federal income taxes for SPCs at Inova Re, which have elected to be taxed as a U.S. corporation under Section 953(d) of the Internal Revenue Code. U.S. federal income taxes are included in the total SPC net results and are paid by the individual SPCs. (3) Represents the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition included as a component of consolidated net investment gains (losses) on the Condensed Consolidated Statements of Income and Comprehensive Income. See further discussion on the contingent consideration in Note 2. (4) Represents the transaction-related costs, after-tax, associated with the acquisition of NORCAL. For the three and six months ended June 30, 2022 pre-tax transaction-related costs of approximately $0.7 million and $1.9 million, respectively, were included as a component of consolidated operating expense and the associated income tax benefit of approximately $0.2 million and $0.4 million, respectively, were included as a component of consolidated income tax benefit (expense) on the Condensed Consolidated Statements of Income and Comprehensive Income.
Schedule of Gross Premiums by Product	The following table provides detailed information regarding ProAssurance's gross premiums earned by product as well as a reconciliation to net premiums earned. All gross premiums earned are from external customers except as noted. ProAssurance's insured risks are primarily within the U.S. Three Months Ended June 30 Six Months Ended June 30 (In thousands) 2023 2022 2023 2022 Specialty P&C Segment Gross premiums earned: HCPL $ 168,928 $ 165,496 $ 331,315 $ 341,043 Small Business Unit 25,931 26,188 52,005 52,726 Medical Technology Liability 10,610 9,968 21,156 19,968 Other — 203 — 397 Ceded premiums earned (26,567) (18,308) (46,231) (32,620) Segment net premiums earned 178,902 183,547 358,245 381,514 Workers' Compensation Insurance Segment Gross premiums earned: Traditional business 44,660 45,395 88,200 88,551 Alternative market business 17,484 18,126 35,110 36,004 Ceded premiums earned (21,126) (21,812) (41,489) (42,162) Segment net premiums earned 41,018 41,709 81,821 82,393 Segregated Portfolio Cell Reinsurance Segment Gross premiums earned: Workers' compensation (1) 16,329 17,092 32,633 34,270 HCPL (2) 10,061 1,504 11,360 5,990 Ceded premiums earned (2,296) (2,374) (4,599) (4,724) Segment net premiums earned 24,094 16,222 39,394 35,536 Lloyd's Syndicates Segment Gross premiums earned: Property and casualty 4,522 6,443 9,568 15,675 Ceded premiums earned (674) (650) (1,379) (2,136) Segment net premiums earned 3,848 5,793 8,189 13,539 Consolidated net premiums earned $ 247,862 $ 247,271 $ 487,649 $ 512,982 (1) Premium for all periods is assumed from the Workers' Compensation Insurance segment. (2) Premium for all periods is assumed from the Specialty P&C segment.

Benefit Plans (Tables)

Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2023
Retirement Benefits [Abstract]
Schedule of Net Periodic Benefit Cost	The components of the net periodic benefit cost (income) for the three and six months ended June 30, 2023 and 2022 were as follows: ($ in thousands) Three Months Ended Six Months Ended 2023 2022 2023 2022 Components of net periodic benefit cost (income): Interest cost $ 914 $ 720 $ 1,818 $ 1,431 Expected return on Plan assets (884) (1,001) (1,758) (1,990) Total net periodic benefit cost (income)* $ 30 $ (281) $ 60 $ (559) *Net periodic benefit cost (income) is included as a component of operating expense on the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2023 and 2022.

Basis of Presentation (Narrativ

Basis of Presentation (Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($) segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments | segment	5
Percent of investments with exposure to LIBOR	1%
Investments with exposure to LIBOR	$ 60
Percent of investments with exposure to LIBOR, with provision for alternative benchmark rate	73%
Refund payments	$ 3.8

Fair Value Measurement (Assets

Fair Value Measurement (Assets Measured at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets:
Fixed maturities, available-for-sale	$ 3,352,331	$ 3,472,472
Fixed maturities, trading	45,732	43,434
Equity investments	149,529	143,738
Level 3
Liabilities:
Other liabilities	11,000	15,000
U.S. Treasury obligations
Assets:
Fixed maturities, available-for-sale	230,214	221,608
U.S. Government-sponsored enterprise obligations
Assets:
Fixed maturities, available-for-sale	18,863	19,934
State and municipal bonds
Assets:
Fixed maturities, available-for-sale	440,231	439,450
Corporate debt, limited observable inputs | Level 3
Assets:
Fixed maturities, available-for-sale	67,394	63,973
Residential mortgage-backed securities
Assets:
Fixed maturities, available-for-sale	376,551	389,540
Agency commercial mortgage-backed securities
Assets:
Fixed maturities, available-for-sale	8,764	9,704
Other commercial mortgage-backed securities
Assets:
Fixed maturities, available-for-sale	190,012	194,090
Other asset-backed securities
Assets:
Fixed maturities, available-for-sale	398,517	416,694
Recurring
Assets:
Total assets categorized within the fair value hierarchy	4,201,410	4,259,889
Recurring | Level 1
Assets:
Fixed maturities, trading	0	0
Other assets	0
Total assets categorized within the fair value hierarchy	349,078	322,534
Liabilities:
Other liabilities	5,450	0
Total liabilities categorized within the fair value hierarchy	5,450	0
Recurring | Level 2
Assets:
Fixed maturities, trading	45,732	43,434
Other assets	5,455
Total assets categorized within the fair value hierarchy	3,507,480	3,603,357
Liabilities:
Other liabilities	0	0
Total liabilities categorized within the fair value hierarchy	0	0
Recurring | Level 3
Assets:
Fixed maturities, trading	0	0
Other assets	0
Total assets categorized within the fair value hierarchy	74,357	71,513
Liabilities:
Other liabilities	11,000	15,000
Total liabilities categorized within the fair value hierarchy	11,000	15,000
Recurring | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, trading	45,732	43,434
Other assets	5,455
Total assets categorized within the fair value hierarchy	3,930,915	3,997,404
Liabilities:
Other liabilities	16,450	15,000
Total liabilities categorized within the fair value hierarchy	16,450	15,000
Recurring | U.S. Treasury obligations | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | U.S. Treasury obligations | Level 2
Assets:
Fixed maturities, available-for-sale	230,214	221,608
Recurring | U.S. Treasury obligations | Level 3
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | U.S. Treasury obligations | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	230,214	221,608
Recurring | U.S. Government-sponsored enterprise obligations | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | U.S. Government-sponsored enterprise obligations | Level 2
Assets:
Fixed maturities, available-for-sale	18,863	19,934
Recurring | U.S. Government-sponsored enterprise obligations | Level 3
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | U.S. Government-sponsored enterprise obligations | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	18,863	19,934
Recurring | State and municipal bonds | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | State and municipal bonds | Level 2
Assets:
Fixed maturities, available-for-sale	440,231	439,450
Recurring | State and municipal bonds | Level 3
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | State and municipal bonds | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	440,231	439,450
Recurring | Corporate debt, multiple observable inputs | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Corporate debt, multiple observable inputs | Level 2
Assets:
Fixed maturities, available-for-sale	1,621,785	1,717,479
Recurring | Corporate debt, multiple observable inputs | Level 3
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Corporate debt, multiple observable inputs | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	1,621,785	1,717,479
Recurring | Corporate debt, limited observable inputs | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Corporate debt, limited observable inputs | Level 2
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Corporate debt, limited observable inputs | Level 3
Assets:
Fixed maturities, available-for-sale	67,394	63,973
Recurring | Corporate debt, limited observable inputs | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	67,394	63,973
Recurring | Residential mortgage-backed securities | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Residential mortgage-backed securities | Level 2
Assets:
Fixed maturities, available-for-sale	376,263	389,291
Recurring | Residential mortgage-backed securities | Level 3
Assets:
Fixed maturities, available-for-sale	288	249
Recurring | Residential mortgage-backed securities | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	376,551	389,540
Recurring | Agency commercial mortgage-backed securities | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Agency commercial mortgage-backed securities | Level 2
Assets:
Fixed maturities, available-for-sale	8,764	9,704
Recurring | Agency commercial mortgage-backed securities | Level 3
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Agency commercial mortgage-backed securities | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	8,764	9,704
Recurring | Other commercial mortgage-backed securities | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Other commercial mortgage-backed securities | Level 2
Assets:
Fixed maturities, available-for-sale	190,012	194,090
Recurring | Other commercial mortgage-backed securities | Level 3
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Other commercial mortgage-backed securities | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	190,012	194,090
Recurring | Other asset-backed securities | Level 1
Assets:
Fixed maturities, available-for-sale	0	0
Recurring | Other asset-backed securities | Level 2
Assets:
Fixed maturities, available-for-sale	397,576	413,989
Recurring | Other asset-backed securities | Level 3
Assets:
Fixed maturities, available-for-sale	941	2,705
Recurring | Other asset-backed securities | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Fixed maturities, available-for-sale	398,517	416,694
Recurring | Financial | Level 1
Assets:
Equity investments	9,884	9,850
Recurring | Financial | Level 2
Assets:
Equity investments	2,219	2,219
Recurring | Financial | Level 3
Assets:
Equity investments	288	303
Recurring | Financial | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Equity investments	12,391	12,372
Recurring | Utilities/Energy | Level 1
Assets:
Equity investments	892	854
Recurring | Utilities/Energy | Level 2
Assets:
Equity investments	0	0
Recurring | Utilities/Energy | Level 3
Assets:
Equity investments	0	0
Recurring | Utilities/Energy | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Equity investments	892	854
Recurring | Industrial | Level 1
Assets:
Equity investments	0	0
Recurring | Industrial | Level 2
Assets:
Equity investments	0	0
Recurring | Industrial | Level 3
Assets:
Equity investments	4,946	2,500
Recurring | Industrial | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Equity investments	4,946	2,500
Recurring | Bond funds | Level 1
Assets:
Equity investments	113,164	112,136
Recurring | Bond funds | Level 2
Assets:
Equity investments	0	0
Recurring | Bond funds | Level 3
Assets:
Equity investments	0	0
Recurring | Bond funds | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Equity investments	113,164	112,136
Recurring | All other | Level 1
Assets:
Equity investments	18,136	15,876
Recurring | All other | Level 2
Assets:
Equity investments	0	0
Recurring | All other | Level 3
Assets:
Equity investments	0	0
Recurring | All other | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Equity investments	18,136	15,876
Recurring | Short-term investments | Level 1
Assets:
Short-term and other investments	205,896	181,937
Recurring | Short-term investments | Level 2
Assets:
Short-term and other investments	109,685	63,376
Recurring | Short-term investments | Level 3
Assets:
Short-term and other investments	0	0
Recurring | Short-term investments | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Short-term and other investments	315,581	245,313
Recurring | Other investments | Level 1
Assets:
Short-term and other investments	1,106	1,881
Recurring | Other investments | Level 2
Assets:
Short-term and other investments	60,681	88,783
Recurring | Other investments | Level 3
Assets:
Short-term and other investments	500	1,783
Recurring | Other investments | Fair Value, Inputs, Level 1, 2 and 3
Assets:
Short-term and other investments	62,287	92,447
Recurring | Equity investments | Fair Value Measured at Net Asset Value Per Share | Investment in unconsolidated subsidiaries
Assets:
Total assets categorized within the fair value hierarchy	$ 270,495	$ 262,485

Fair Value Measurement (Quantit

Fair Value Measurement (Quantitative Information Regarding Level 3 Valuations) (Details) $ in Thousands	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Assets:
Estimated Fair Value	$ 3,352,331	$ 3,472,472
Other investments	270,495	262,485
Level 3
Assets:
Equity investments	5,234	2,803
Other investments	500	1,783
Liabilities:
Other liabilities	$ 11,000	15,000
Level 3 | Comparability Adjustment | Minimum
Assets:
Equity securities measured at fair value	0
Level 3 | Comparability Adjustment | Maximum
Assets:
Equity securities measured at fair value	0.10
Level 3 | Comparability Adjustment | Weighted Average
Assets:
Equity securities measured at fair value	0.05
Level 3 | Comparability Adjustment | Discounted Cash Flows | Minimum
Assets:
Other investments, measurement input	0
Level 3 | Comparability Adjustment | Discounted Cash Flows | Maximum
Assets:
Other investments, measurement input	0.10
Level 3 | Comparability Adjustment | Discounted Cash Flows | Weighted Average
Assets:
Other investments, measurement input	0.05
Level 3 | Comparability Adjustment | Stochastic Model/Discounted Cash Flows | Minimum
Liabilities:
Other liabilities, measurement input	0%
Level 3 | Comparability Adjustment | Stochastic Model/Discounted Cash Flows | Maximum
Liabilities:
Other liabilities, measurement input	10%
Level 3 | Comparability Adjustment | Stochastic Model/Discounted Cash Flows | Weighted Average
Liabilities:
Other liabilities, measurement input	9%
Corporate debt, limited observable inputs | Level 3
Assets:
Estimated Fair Value	$ 67,394	63,973
Corporate debt, limited observable inputs | Level 3 | Comparability Adjustment | Market Comparable Securities | Minimum
Assets:
Assets measured at fair value	0
Corporate debt, limited observable inputs | Level 3 | Comparability Adjustment | Market Comparable Securities | Maximum
Assets:
Assets measured at fair value	0.05
Corporate debt, limited observable inputs | Level 3 | Comparability Adjustment | Market Comparable Securities | Weighted Average
Assets:
Assets measured at fair value	0.025
Corporate debt, limited observable inputs | Level 3 | Comparability Adjustment | Discounted Cash Flows | Minimum
Assets:
Assets measured at fair value	0
Corporate debt, limited observable inputs | Level 3 | Comparability Adjustment | Discounted Cash Flows | Maximum
Assets:
Assets measured at fair value	0.05
Corporate debt, limited observable inputs | Level 3 | Comparability Adjustment | Discounted Cash Flows | Weighted Average
Assets:
Assets measured at fair value	0.025
Residential mortgage-backed securities | Level 3
Assets:
Estimated Fair Value	$ 288	249
Residential mortgage-backed securities | Level 3 | Comparability Adjustment | Market Comparable Securities | Minimum
Assets:
Assets measured at fair value	0
Residential mortgage-backed securities | Level 3 | Comparability Adjustment | Market Comparable Securities | Maximum
Assets:
Assets measured at fair value	0.05
Residential mortgage-backed securities | Level 3 | Comparability Adjustment | Market Comparable Securities | Weighted Average
Assets:
Assets measured at fair value	0.025
Residential mortgage-backed securities | Level 3 | Comparability Adjustment | Discounted Cash Flows | Minimum
Assets:
Assets measured at fair value	0
Residential mortgage-backed securities | Level 3 | Comparability Adjustment | Discounted Cash Flows | Maximum
Assets:
Assets measured at fair value	0.05
Residential mortgage-backed securities | Level 3 | Comparability Adjustment | Discounted Cash Flows | Weighted Average
Assets:
Assets measured at fair value	0.025
Other asset-backed securities | Level 3
Assets:
Estimated Fair Value	$ 941	$ 2,705
Other asset-backed securities | Level 3 | Comparability Adjustment | Market Comparable Securities | Minimum
Assets:
Assets measured at fair value	0
Other asset-backed securities | Level 3 | Comparability Adjustment | Market Comparable Securities | Maximum
Assets:
Assets measured at fair value	0.05
Other asset-backed securities | Level 3 | Comparability Adjustment | Market Comparable Securities | Weighted Average
Assets:
Assets measured at fair value	0.025
Other asset-backed securities | Level 3 | Comparability Adjustment | Discounted Cash Flows | Minimum
Assets:
Assets measured at fair value	0
Other asset-backed securities | Level 3 | Comparability Adjustment | Discounted Cash Flows | Maximum
Assets:
Assets measured at fair value	0.05
Other asset-backed securities | Level 3 | Comparability Adjustment | Discounted Cash Flows | Weighted Average
Assets:
Assets measured at fair value	0.025

Fair Value Measurement (Level 3

Fair Value Measurement (Level 3 Assets and Liability) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 84,511	$ 68,568	$ 71,513	$ 57,565
Included in earnings, as a part of:
Included in earnings		(787)
Operating Expense			0
Included in other comprehensive income (loss)	(155)	(1,496)	$ 93	(2,749)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]			Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
Purchases	7,255	10,260	$ 15,440	27,039
Sales	(3,991)	(2,199)	(4,423)	(3,339)
Transfers in		20,523	12,999	22,052
Transfers out	(12,500)	(11,093)	(20,515)	(16,116)
Ending balance	74,357	83,776	74,357	83,776
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	(737)	(787)	$ (740)	(723)
Fair Value Asset Recurring Basis Still Held Unrealized Gain Loss Statement Of Income Extensible List Not Disclosed Flag			Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	(13,000)	(24,000)	$ (15,000)	(24,000)
Total gains (losses) realized and unrealized:
Net investment gains (losses)		0
Operating expense			1,000
Included in other comprehensive income (loss)	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Transfers in		0	0	0
Transfers out	0	0	0	0
Ending balance	(11,000)	(24,000)	(11,000)	(24,000)
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	0	0	0	0
Net investment gains (losses)
Included in earnings, as a part of:
Included in earnings	(740)		$ (727)	(677)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Gain (Loss) on Investments
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Gain (Loss) on Investments
Total gains (losses) realized and unrealized:
Net investment gains (losses)	2,000		$ 3,000	0
Net Investment Income
Included in earnings, as a part of:
Included in earnings	(23)		$ (23)	1
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Net investment income (loss)
Total gains (losses) realized and unrealized:
Net investment gains (losses)	0		$ 0	0
Corporate Debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	76,157	53,325	63,973	47,129
Included in earnings, as a part of:
Included in earnings		0
Operating Expense			0
Included in other comprehensive income (loss)	(142)	(1,319)	67	(2,312)
Purchases	4,084	8,787	10,406	18,498
Sales	(3,595)	(2,007)	(4,027)	(3,026)
Transfers in		17,828	11,220	18,828
Transfers out	(9,084)	(2,402)	(14,235)	(4,905)
Ending balance	67,394	74,212	67,394	74,212
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	0	0	0	0
Corporate Debt | Net investment gains (losses)
Included in earnings, as a part of:
Included in earnings	(3)		13	0
Corporate Debt | Net Investment Income
Included in earnings, as a part of:
Included in earnings	(23)		(23)	0
Asset-backed Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	5,054	9,303	2,954	6,502
Included in earnings, as a part of:
Included in earnings		0
Operating Expense			0
Included in other comprehensive income (loss)	(13)	(177)	26	(437)
Purchases	0	1,473	1,863	7,058
Sales	(396)	(192)	(396)	(197)
Transfers in		570	1,779	570
Transfers out	(3,416)	(6,939)	(4,997)	(9,459)
Ending balance	1,229	4,038	1,229	4,038
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	0	0	0	0
Asset-backed Securities | Net investment gains (losses)
Included in earnings, as a part of:
Included in earnings	0		0	0
Asset-backed Securities | Net Investment Income
Included in earnings, as a part of:
Included in earnings	0		0	1
Equity Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	2,800	2,500	2,803	2,500
Included in earnings, as a part of:
Included in earnings		0
Operating Expense			0
Included in other comprehensive income (loss)	0	0	0	0
Purchases	3,171	0	3,171	0
Sales	0	0	0	0
Transfers in		2,125	0	2,125
Transfers out	0	0	0	0
Ending balance	5,234	4,625	5,234	4,625
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	(737)	0	(740)	0
Equity Investments | Net investment gains (losses)
Included in earnings, as a part of:
Included in earnings	(737)		(740)
Equity Investments | Net Investment Income
Included in earnings, as a part of:
Included in earnings	0		0
Other Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	500	3,440	1,783	1,434
Included in earnings, as a part of:
Included in earnings		(787)
Operating Expense			0
Included in other comprehensive income (loss)	0	0	0	0
Purchases	0	0	0	1,483
Sales	0	0	0	(116)
Transfers in		0	0	529
Transfers out	0	(1,752)	(1,283)	(1,752)
Ending balance	500	901	500	901
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	0	(787)	0	(723)
Other Investments | Net investment gains (losses)
Included in earnings, as a part of:
Included in earnings	0		0	(677)
Other Investments | Net Investment Income
Included in earnings, as a part of:
Included in earnings	0		0	0
Other Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	(13,000)		(15,000)	(24,000)
Total gains (losses) realized and unrealized:
Operating expense			1,000
Included in other comprehensive income (loss)	0	0	0	0
Purchases	0	0	0	0
Sales	0	0	0	0
Transfers in		0	0	0
Transfers out	0	0	0	0
Ending balance	(11,000)	(24,000)	(11,000)	(24,000)
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets and liabilities held at period-end	0	0	0	0
Other Liabilities | Net investment gains (losses)
Total gains (losses) realized and unrealized:
Net investment gains (losses)	2,000		3,000
Operating expense				0
Other Liabilities | Net Investment Income
Included in earnings, as a part of:
Operating Expense		$ 0
Total gains (losses) realized and unrealized:
Net investment gains (losses)	$ 0		$ 0
Operating expense				$ 0

Fair Value Measurement (Investm

Fair Value Measurement (Investments in LLCs and Limited Partnerships) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($) fund	Dec. 31, 2022 USD ($)
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 270,495	$ 262,485
Private debt funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Number of limited partners in investment | fund	2
Number of limited partners to allow redemption by special consent | fund	1
Private debt funds | Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	3 years
Private debt funds | Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	8 years
Private debt funds | Investment in unconsolidated subsidiaries
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 1,885
Fair Value	$ 19,970	19,620
Long/short equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Payment period for redemption of LP valued at NAV	30 days
Long/short equity funds | Investment in unconsolidated subsidiaries
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 0
Fair Value	$ 4,876	5,089
Non-public equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	10 years
Non-public equity funds | Investment in unconsolidated subsidiaries
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 51,582
Fair Value	$ 144,908	144,560
Credit funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Number of limited partners to allow redemption by special consent | fund	1
Investment redemption notice period	180 days
Credit funds | Investment in unconsolidated subsidiaries
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 31,251
Fair Value	50,178	49,245
Strategy focused funds | Investment in unconsolidated subsidiaries
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	9,016
Fair Value	$ 50,563	$ 43,971

Fair Value Measurement (Narrati

Fair Value Measurement (Narrative) (Details)	Jun. 30, 2023 USD ($) subsidiary	Dec. 31, 2022 USD ($)
Credit Derivatives [Line Items]
Fair value of funded deferred compensation assets	$ 30,500,000	$ 27,900,000
FHLB
Credit Derivatives [Line Items]
Number of proassurance's insurance subsidiaries | subsidiary	3
Fair Value
Credit Derivatives [Line Items]
Deferred compensation liabilities	$ 30,200,000	27,900,000
Fair Value, Nonrecurring
Credit Derivatives [Line Items]
Fair value, net asset (liability)	$ 0	$ 0

Fair Value Measurement (Financi

Fair Value Measurement (Financial Instruments Not Measured at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Carrying Value
Financial assets:
Other assets	$ 31,464	$ 28,819
Financial liabilities:
Other liabilities	30,241	27,905
Carrying Value | Senior notes due 2023
Financial liabilities:
Senior notes due 2023	250,000	250,000
Carrying Value | Contribution Certificates
Financial liabilities:
Contribution Certificates	178,437	177,525
Carrying Value | BOLI
Financial assets:
Short-term and other investments	80,930	81,746
Carrying Value | Other investments
Financial assets:
Short-term and other investments	3,000	3,322
Fair Value
Financial assets:
Other assets	31,432	28,790
Financial liabilities:
Other liabilities	30,241	27,905
Fair Value | Senior notes due 2023
Financial liabilities:
Senior notes due 2023	248,463	248,153
Fair Value | Contribution Certificates
Financial liabilities:
Contribution Certificates	132,515	134,479
Fair Value | BOLI
Financial assets:
Short-term and other investments	80,930	81,746
Fair Value | Other investments
Financial assets:
Short-term and other investments	$ 3,000	$ 3,322

Investments (Available-For-Sale

Investments (Available-For-Sale Fixed Maturities) (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]
Amortized Cost	$ 3,699,049		$ 3,852,411
Allowance for Expected Credit Losses	419	$ 424	427	$ 553	$ 0	$ 0
Gross Unrealized Gains	2,116		1,827
Gross Unrealized Losses	348,415		381,339
Estimated Fair Value	3,352,331		3,472,472
U.S. Treasury obligations
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	251,504		243,999
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	44		8
Gross Unrealized Losses	21,334		22,399
Estimated Fair Value	230,214		221,608
U.S. Government-sponsored enterprise obligations
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	20,339		21,562
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	1		0
Gross Unrealized Losses	1,477		1,628
Estimated Fair Value	18,863		19,934
State and municipal bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	476,863		483,584
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	351		177
Gross Unrealized Losses	36,983		44,311
Estimated Fair Value	440,231		439,450
Corporate debt
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	1,871,577		1,980,579
Allowance for Expected Credit Losses	0		0	$ 553	$ 0	$ 0
Gross Unrealized Gains	903		735
Gross Unrealized Losses	183,301		199,862
Estimated Fair Value	1,689,179		1,781,452
Residential mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	435,406		450,870
Allowance for Expected Credit Losses	223	$ 227	229
Gross Unrealized Gains	485		555
Gross Unrealized Losses	59,117		61,656
Estimated Fair Value	376,551		389,540
Agency commercial mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	9,733		10,576
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	0		0
Gross Unrealized Losses	969		872
Estimated Fair Value	8,764		9,704
Other commercial mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	213,545		217,021
Allowance for Expected Credit Losses	0		0
Gross Unrealized Gains	35		63
Gross Unrealized Losses	23,568		22,994
Estimated Fair Value	190,012		194,090
Other asset-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	420,082		444,220
Allowance for Expected Credit Losses	196		198
Gross Unrealized Gains	297		289
Gross Unrealized Losses	21,666		27,617
Estimated Fair Value	$ 398,517		$ 416,694

Investments (Available-For-Sa_2

Investments (Available-For-Sale Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 3,699,049	$ 3,852,411
Total Fair Value	3,352,331	3,472,472
U.S. Treasury obligations
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	251,504	243,999
Due in one year or less	26,685
Due after one year through five years	167,068
Due after five years through ten years	33,749
Due after ten years	2,712
Total Fair Value	230,214	221,608
U.S. Government-sponsored enterprise obligations
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	20,339	21,562
Due in one year or less	2,676
Due after one year through five years	12,714
Due after five years through ten years	3,473
Due after ten years	0
Total Fair Value	18,863	19,934
State and municipal bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	476,863	483,584
Due in one year or less	33,736
Due after one year through five years	149,666
Due after five years through ten years	148,179
Due after ten years	108,650
Total Fair Value	440,231	439,450
Corporate debt
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	1,871,577	1,980,579
Due in one year or less	207,118
Due after one year through five years	825,556
Due after five years through ten years	570,714
Due after ten years	85,791
Total Fair Value	1,689,179	1,781,452
Residential mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	435,406	450,870
Total Fair Value	376,551	389,540
Agency commercial mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	9,733	10,576
Total Fair Value	8,764	9,704
Other commercial mortgage-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	213,545	217,021
Total Fair Value	190,012	194,090
Other asset-backed securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	420,082	444,220
Total Fair Value	$ 398,517	$ 416,694

Investments (Narrative) (Detail

Investments (Narrative) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($) security issuer investment business	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) security issuer investment business	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) security business issuer
Debt Securities, Available-for-Sale [Line Items]
Number of investment in any entity or affiliates greater than 10% of stockholders' equity | investment	0		0
Threshold limit of investments based on shareholders' equity	10%		10%
Securities on deposit with state insurance departments	$ 56,700,000		$ 56,700,000
FAL Deposit return by cash	4,100,000		4,100,000
Investment in unconsolidated subsidiaries	$ 306,027,000		$ 306,027,000		$ 305,210,000
Number of LPs / LLCs with investment ownership percent over 25% (in businesses) | business	4		4		3
Net impairment losses recognized in earnings	$ (43,000)	$ (553,000)	$ (2,976,000)	$ (553,000)
Portion of impairment losses recognized in other comprehensive income (loss) before taxes	0	419,000	0	419,000
Asset Pledged as Collateral
Debt Securities, Available-for-Sale [Line Items]
Securities on deposit with state insurance departments	107,800,000		107,800,000
Tax Year 2019
Debt Securities, Available-for-Sale [Line Items]
Tax credit partnership investments			1,900,000	2,000,000
Tax Year 2039
Debt Securities, Available-for-Sale [Line Items]
Tax credit carryforwards	53,200,000		53,200,000
Tax Credit Partnership Investment Tax Credit Carryforward | Tax Year 2020
Debt Securities, Available-for-Sale [Line Items]
Tax credit partnership investments		$ 1,200,000		$ 2,400,000
Tax Credit Partnerships Less Than 20% Ownership
Debt Securities, Available-for-Sale [Line Items]
Investment in unconsolidated subsidiaries	$ 1,200,000		$ 1,200,000		$ 4,100,000
Tax Credit Partnerships Less Than 20% Ownership | Maximum
Debt Securities, Available-for-Sale [Line Items]
Investment ownership percentage	20%		20%
Other Limited Partnerships and Limited Liability Company, Greater Than 25% Ownership
Debt Securities, Available-for-Sale [Line Items]
Investment ownership percentage	25%		25%
Investment in unconsolidated subsidiaries	$ 46,000,000		$ 46,000,000		36,000,000
Other Limited Partnerships and Limited Liability Company Less than 25% Ownership
Debt Securities, Available-for-Sale [Line Items]
Investment in unconsolidated subsidiaries	258,800,000		258,800,000		$ 265,100,000
Fixed maturities
Debt Securities, Available-for-Sale [Line Items]
Required FAL deposit	18,700,000		18,700,000
Cash and cash equivalents
Debt Securities, Available-for-Sale [Line Items]
Required FAL deposit	$ 600,000		$ 600,000
Non government-backed
Debt Securities, Available-for-Sale [Line Items]
Debt securities in unrealized loss position (in securities) | security	2,781		2,781		2,901
Debt securities in unrealized loss position as percentage of total debt securities held	73%		73%		74.40%
Issuers in unrealized loss position (in issuers) | issuer	1,402		1,402		1,433
Single greatest unrealized loss position	$ 5,500,000		$ 5,500,000		$ 5,700,000
Second greatest unrealized loss position	$ 3,600,000		$ 3,600,000		$ 4,100,000

Investments (Investments Held i

Investments (Investments Held in a Loss Position) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair value
Fair Value	$ 3,187,086	$ 3,333,683
Less than 12 months, Fair Value	673,179	1,300,381
12 months or longer, Fair Value	2,513,907	2,033,302
Unrealized Loss
Unrealized Loss	348,415	381,339
Less than 12 months, Unrealized Loss	39,493	84,907
12 months or longer, Unrealized Loss	308,922	296,432
U.S. Treasury obligations
Fair value
Fair Value	224,346	220,991
Less than 12 months, Fair Value	72,417	53,199
12 months or longer, Fair Value	151,929	167,792
Unrealized Loss
Unrealized Loss	21,334	22,399
Less than 12 months, Unrealized Loss	5,047	2,393
12 months or longer, Unrealized Loss	16,287	20,006
U.S. Government-sponsored enterprise obligations
Fair value
Fair Value	18,746	19,934
Less than 12 months, Fair Value	6,625	8,082
12 months or longer, Fair Value	12,121	11,852
Unrealized Loss
Unrealized Loss	1,477	1,628
Less than 12 months, Unrealized Loss	419	663
12 months or longer, Unrealized Loss	1,058	965
State and municipal bonds
Fair value
Fair Value	411,244	421,769
Less than 12 months, Fair Value	103,378	177,393
12 months or longer, Fair Value	307,866	244,376
Unrealized Loss
Unrealized Loss	36,983	44,311
Less than 12 months, Unrealized Loss	4,625	12,352
12 months or longer, Unrealized Loss	32,358	31,959
Corporate debt
Fair value
Fair Value	1,614,792	1,708,529
Less than 12 months, Fair Value	298,741	687,947
12 months or longer, Fair Value	1,316,051	1,020,582
Unrealized Loss
Unrealized Loss	183,301	199,862
Less than 12 months, Unrealized Loss	15,412	42,977
12 months or longer, Unrealized Loss	167,889	156,885
Residential mortgage-backed securities
Fair value
Fair Value	341,913	363,945
Less than 12 months, Fair Value	92,609	155,212
12 months or longer, Fair Value	249,304	208,733
Unrealized Loss
Unrealized Loss	59,117	61,656
Less than 12 months, Unrealized Loss	9,871	15,275
12 months or longer, Unrealized Loss	49,246	46,381
Agency commercial mortgage-backed securities
Fair value
Fair Value	8,764	9,704
Less than 12 months, Fair Value	1,822	3,086
12 months or longer, Fair Value	6,942	6,618
Unrealized Loss
Unrealized Loss	969	872
Less than 12 months, Unrealized Loss	93	110
12 months or longer, Unrealized Loss	876	762
Other commercial mortgage-backed securities
Fair value
Fair Value	189,038	192,359
Less than 12 months, Fair Value	26,552	53,270
12 months or longer, Fair Value	162,486	139,089
Unrealized Loss
Unrealized Loss	23,568	22,994
Less than 12 months, Unrealized Loss	1,991	4,087
12 months or longer, Unrealized Loss	21,577	18,907
Other asset-backed securities
Fair value
Fair Value	378,243	396,452
Less than 12 months, Fair Value	71,035	162,192
12 months or longer, Fair Value	307,208	234,260
Unrealized Loss
Unrealized Loss	21,666	27,617
Less than 12 months, Unrealized Loss	2,035	7,050
12 months or longer, Unrealized Loss	$ 19,631	$ 20,567

Investments (Credit Losses Rela

Investments (Credit Losses Related to Debt Securities) (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 [Roll Forward]
Allowance for credit loss beginning balance	$ 424	$ 0	$ 427	$ 0
Securities sold during the period	(5)		(8)	553
No allowance for credit losses has been previously recognized		553
Allowance for credit loss ending balance	419	553	419	553
Residential mortgage-backed securities
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	227		229
Securities sold during the period	(4)		(6)
Allowance for credit loss ending balance	223		223
Other asset-backed securities
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance	197		198
Securities sold during the period	(1)		(2)
Allowance for credit loss ending balance	196		196
Corporate Debt
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Allowance for credit loss beginning balance		0	0	0
Securities sold during the period				553
No allowance for credit losses has been previously recognized		553
Allowance for credit loss ending balance	$ 0	$ 553	$ 0	$ 553

Investments (Sales and Purchase

Investments (Sales and Purchases of Available-for-Sale Securities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Information regarding sales and purchases of available-for-sale securities
Proceeds from sales (exclusive of maturities and paydowns)	$ 19,600	$ 38,800	$ 23,400	$ 102,300
Purchases	$ 65,400	$ 109,100	$ 134,223	$ 340,746

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
Investment fees and expenses	$ (1,899)	$ (2,017)	$ (3,730)	$ (4,198)
Net investment income	31,650	21,944	61,960	42,387
Fixed maturities
Net Investment Income
Net investment income (loss)	27,951	22,006	55,278	43,550
Equities
Net Investment Income
Net investment income (loss)	1,105	967	1,912	1,668
Short-term investments, including Other
Net Investment Income
Net investment income (loss)	4,034	727	7,384	1,153
BOLI
Net Investment Income
BOLI	$ 459	$ 261	$ 1,116	$ 214

Investments (Unconsolidated Sub

Investments (Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated subsidiaries	$ 306,027	$ 305,210
Qualified affordable housing project tax credit partnerships
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated subsidiaries	1,216	4,088
All other investments, primarily investment fund LPs/LLCs
Schedule of Equity Method Investments [Line Items]
Investment in unconsolidated subsidiaries	$ 304,811	$ 301,122

Investments (Equity in Earnings

Investments (Equity in Earnings (Loss) of Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Losses recorded	$ 1,511	$ 2,809	$ 1,865	$ 5,197
Tax credits recognized	29	1,198	72	2,403
Losses (gains) recorded	$ 0	$ (961)	$ 0	$ (961)

Investments (Summarized Financi

Investments (Summarized Financial Information for Significant Investment) (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 (loss)	$ 31,650	$ 21,944	$ 61,960	$ 42,387
Total net investment gains (losses)	2,946	(23,884)	5,858	(37,390)
Net gain (loss) attributable to proassurance	$ 10,627	$ (1,659)	4,453	(5,219)
Significant Equity Method Investees
Schedule of Equity Method Investments [Line Items]
Net investment income (loss)			(11,800)	6,042
Net investment gains (losses)			43,369	71,001
Net change in unrealized appreciation (depreciation)			53,349	186,575
Total net investment gains (losses)			84,918	263,618
Net gain (loss) attributable to proassurance			$ 464	$ 4,033

Investments (Net Realized Inves

Investments (Net Realized Investment Gains (Losses)) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Securities, Available-for-Sale [Line Items]
Total impairment losses:	$ (43,000)	$ (972,000)	$ (2,976,000)	$ (972,000)
Corporate debt	0	419,000	0	419,000
Net impairment losses recognized in earnings	(43,000)	(553,000)	(2,976,000)	(553,000)
Gross realized gains, available-for-sale fixed maturities	460,000	265,000	539,000	1,452,000
Gross realized (losses), available-for-sale fixed maturities	(767,000)	(965,000)	(1,224,000)	(2,089,000)
Net realized gains (losses), trading fixed maturities	2,000	(21,000)	(106,000)	(97,000)
Net realized gains (losses), equity investments	17,000	(5,125,000)	101,000	(5,346,000)
Net realized gains (losses), other investments	(2,115,000)	(760,000)	(1,886,000)	(110,000)
Change in unrealized holding gains (losses), trading fixed maturities	54,000	(455,000)	151,000	(781,000)
Change in unrealized holding gains (losses), equity investments	(1,130,000)	(5,923,000)	2,616,000	(17,408,000)
Change in unrealized holding gains (losses), convertible securities, carried at fair value	2,929,000	(10,584,000)	4,061,000	(13,059,000)
Other	3,539,000	237,000	4,582,000	601,000
Total net investment gains (losses)	2,946,000	(23,884,000)	5,858,000	(37,390,000)
Corporate Debt
Debt Securities, Available-for-Sale [Line Items]
Total impairment losses:	(48,000)	(972,000)	(2,984,000)	(972,000)
Asset-backed securities
Debt Securities, Available-for-Sale [Line Items]
Total impairment losses:	5,000	$ 0	8,000	$ 0
NORCAL Group
Debt Securities, Available-for-Sale [Line Items]
Gain on fair value of contingent consideration	$ 2,000,000		$ 3,000,000

Investments (Roll Forward of Cu

Investments (Roll Forward of Cumulative Credit Losses Recorded in Earnings) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Balance beginning of period	$ 57	$ 0	$ 57	$ 0
No impairment has been previously recognized	0	553	0	553
Balance ending of period	$ 57	$ 553	$ 57	$ 553

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Income Tax Contingency [Line Items]
Decrease in contingent consideration liability	$ 4
Income taxes payable	(5.2)
Income taxes receivable		$ 8
Unrecognized tax benefits	4.1
Accrued liability for interest related to unrecognized tax benefits	0.5
Tax Year 2020
Income Tax Contingency [Line Items]
Operating loss carryforwards	33.3
Income tax refund, CARES Act	$ 11.7

Reserve for Losses and Loss A_3

Reserve for Losses and Loss Adjustment Expenses (Details) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) claim	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Liability for Claims and Claims Adjustment Expense [Line Items]
Minimum period for claims resolution		5 years
Summary of reserve for losses and loss adjustment expenses
Balance, beginning of year		$ 3,471,147	$ 3,579,940	$ 3,579,940
Less reinsurance recoverables on unpaid losses and loss adjustment expenses		431,889	451,741	451,741
Net balance, beginning of year		3,039,258	3,128,199	3,128,199
Net losses:
Current year		395,632	411,397	813,515
Favorable development of reserves established in prior years, net		722	(24,304)	(36,753)
Total		396,354	387,093	776,762
Paid related to:
Current year		(33,129)	(44,903)	(108,139)
Prior years		(407,118)	(366,643)	(757,564)
Total paid		(440,247)	(411,546)	(865,703)
Net balance, end of period	$ 3,103,746	2,995,365	3,103,746	3,039,258
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses	469,116	425,560	469,116	431,889
Balance, end of period	3,572,862	$ 3,420,925	3,572,862	3,471,147
Number of claims | claim		4
Net unfavorable prior year reserve development		$ 10,100	4,000
Net unfavorable prior year reserve development, years 2016 and 2020		$ 7,500
Number of claims, net unfavorable prior year reserve development, from 1997 accident year | claim		1
Specialty P&C Segment
Net losses:
Favorable development of reserves established in prior years, net	3,000			9,000
Paid related to:
Increase in reserve for potential ECO/XPL claims	$ 4,000		4,000
NORCAL Group
Net losses:
Current year			4,900	4,900
Favorable development of reserves established in prior years, net		$ 5,000	$ 5,800	$ 10,800

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Nov. 30, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	May 05, 2021
NORCAL Group
Other Commitments [Line Items]
Contingent consideration, maximum estimate							$ 84
Fair value of contingent consideration in NORCAL acquisition		$ (11)		$ (11)		$ (15)
Data Analytics Services
Other Commitments [Line Items]
Non-renew notice, period				6 months
Annual fee	$ 3.5
Purchase commitment, period	3 years
Extension period for long-term purchase commitment				1 year
Operating expense		0.8	$ 0.9	$ 1.7	$ 1.8
Purchase obligation		4.6		4.6
Funding Commitments
Other Commitments [Line Items]
Commitments total		178.5		$ 178.5
Lloyd's Syndicates
Other Commitments [Line Items]
Non-renew notice, period				30 days
Auto-renewal period prior to maturity date				1 year
Required FAL deposit		19.3		$ 19.3
Settlement received		$ 4.1

Debt (Details)

Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Gross debt	$ 428,437	$ 427,525
Less unamortized debt issuance costs	2,411	542
Debt less unamortized debt issuance costs	426,026	426,983
Senior notes due 2023 | Senior Notes
Debt Instrument [Line Items]
Gross debt	$ 250,000	250,000
Stated interest rate on debt	5.30%
Contribution Certificates
Debt Instrument [Line Items]
Gross debt	$ 178,437	$ 177,525
Stated interest rate on debt	3%
Effective interest rate on debt	4.35%

Debt (Narrative) (Details)

Debt (Narrative) (Details) - Line of Credit - Revolving Credit Facility		6 Months Ended
	Apr. 28, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Construction loan	$ 125,000,000
Delayed term loan period	5 years
Line of credit borrowing capacity		$ 250,000,000
Accordion feature borrowing capacity		50,000,000
Line of credit, borrowing capacity including accordion feature		300,000,000
Outstanding borrowing		$ 0	$ 0
Maximum allowable consolidated funded indebtedness ratio (percent)		0.35
Minimum net worth required		$ 912,000,000
Minimum liquidity required		$ 25,000,000
Federal Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate for debt		0.50%
One Month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate for debt		1%
Minimum
Debt Instrument [Line Items]
Commitment fee percentages (percent)		0.20%
Maximum
Debt Instrument [Line Items]
Commitment fee percentages (percent)		0.45%

Derivatives (Narrative) (Detail

Derivatives (Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($) derivative_instrument
Derivative [Line Items]
Number of instruments (in derivative instruments) | derivative_instrument	2
Interest Rate Swap
Derivative [Line Items]
Interest rate swaps	$ 5.5
Expected gains reclassified	2.4
Revolving Credit Agreement | Interest Rate Swap
Derivative [Line Items]
Derivative, notional amount	125
Term Loan | Interest Rate Swap
Derivative [Line Items]
Derivative, notional amount	$ 125
Line of Credit | Revolving Credit Agreement | Secured Overnight Financing Rate (SOFR)
Derivative [Line Items]
Derivative, fixed interest rate	3.187%
Line of Credit | Minimum | Revolving Credit Agreement
Derivative [Line Items]
Basis spread on variable rate for debt	0%
Line of Credit | Maximum | Term Loan
Derivative [Line Items]
Basis spread on variable rate for debt	2.375%
Line of Credit | Maximum | Term Loan | Secured Overnight Financing Rate (SOFR)
Derivative [Line Items]
Derivative, fixed interest rate	3.207%

Derivatives (Volume and Fair Va

Derivatives (Volume and Fair Value) (Details) $ in Thousands	Jun. 30, 2023 USD ($) derivative_instrument
Derivative [Line Items]
Number of instruments (in derivative instruments) | derivative_instrument	2
Interest Rate Swap | Cash Flow Hedging
Derivative [Line Items]
Number of instruments (in derivative instruments) | derivative_instrument	2
Notional amount | $	$ 250,000
Estimated fair value | $	$ 5,455

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Equity [Abstract]
Common shares, shares authorized (in shares)	100,000,000				100,000,000		100,000,000
Preferred stock, shares authorized (in shares)	50,000,000				50,000,000		50,000,000
Cash dividends declared per common share (in usd per share)	$ 0	$ 0.05	$ 0.05	$ 0.05	$ 0.05	$ 0.10
Dividend declared					$ 2,700	$ 5,400
Total authorizations which remain available for use	$ 86,400				$ 86,400
Common shares acquired (in shares)					1,400,000	0
Common shares, at cost	19,971				$ 19,971
Deferred tax (benefit) expense included in OCI	$ 2,700		$ 29,600		$ 8,100	$ 67,800

Shareholders' Equity (Roll Forw

Shareholders' Equity (Roll Forward of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 1,138,290	$ 1,281,768	$ 1,104,018	$ 1,428,387
OCI, before reclassifications, net of tax	(11,764)	(110,522)	28,243	(251,330)
Amounts reclassified from AOCI, net of tax	262	900	2,884	858
Net OCI, current period	(11,502)	(109,622)	31,127	(250,472)
Ending balance	1,119,714	1,169,889	1,119,714	1,169,889
Unrealized Investment Gains (Losses) on Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(254,513)	(125,907)	(297,142)	14,929
OCI, before reclassifications, net of tax	(16,074)	(110,191)	23,933	(250,999)
Amounts reclassified from AOCI, net of tax	262	1,053	2,884	1,025
Net OCI, current period	(15,812)	(109,138)	26,817	(249,974)
Ending balance	(270,325)	(235,045)	(270,325)	(235,045)
Unrealized Investment Gains (Losses) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0		0
OCI, before reclassifications, net of tax	4,310		4,310
Amounts reclassified from AOCI, net of tax	0		0
Net OCI, current period	4,310		4,310
Ending balance	4,310		4,310
Non-credit Impairments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(11)	0	(11)	0
OCI, before reclassifications, net of tax	0	(331)	0	(331)
Amounts reclassified from AOCI, net of tax	0	0	0	0
Net OCI, current period	0	(331)	0	(331)
Ending balance	(11)	(331)	(11)	(331)
Unrecognized Change in Defined Benefit Plan Liabilities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,454)	1,341	(1,454)	1,355
OCI, before reclassifications, net of tax	0	0	0	0
Amounts reclassified from AOCI, net of tax	0	(153)	0	(167)
Net OCI, current period	0	(153)	0	(167)
Ending balance	(1,454)	1,188	(1,454)	1,188
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(255,978)	(124,566)	(298,607)	16,284
Ending balance	$ (267,480)	$ (234,188)	$ (267,480)	$ (234,188)

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
VIEs carrying value	$ 5,657,412	$ 5,699,999
Liabilities	4,537,698	4,595,981
Variable Interest Entity, Primary Beneficiary | PPM RRG
Variable Interest Entity [Line Items]
VIEs carrying value	134,000	154,000
Surplus Notes	5,000
Liabilities	134,000	154,000
Equity investments | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
VIEs carrying value	$ 277,600	$ 277,500

Earnings (Loss) Per Share (Earn

Earnings (Loss) Per Share (Earnings Per Share) (Details) - $ / shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average number of common shares outstanding, basic (in shares)	53,815	54,068	53,900	54,040
Weighted average number of common shares outstanding, diluted (in shares)	53,918	54,186	54,017	54,165
Effect of dilutive shares on earnings (loss) per share (in usd per share)	$ 0	$ 0	$ 0	$ 0
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive securities (in shares)	87	104	95	109
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive securities (in shares)	16	14	22	16

Earnings (Loss) Per Share (Narr

Earnings (Loss) Per Share (Narrative) (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Antidilutive shares excluded from computation of earnings per share (in shares)	339	4	170	2

Segment Information (Narrative)

Segment Information (Narrative) (Details)	6 Months Ended
	Jun. 30, 2023 segment
Segment Reporting Information [Line Items]
Number of reportable segments	5
Number of operating segments	5
Syndicate 1729
Segment Reporting Information [Line Items]
Proportion of capital provided to support Lloyd's Syndicate	5%

Segment Information (Financial

Segment Information (Financial Data 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	$ 247,862	$ 247,271	$ 487,649	$ 512,982
Net investment income	31,650	21,944	61,960	42,387
Equity in earnings (loss) of unconsolidated subsidiaries	6,632	5,180	5,511	12,799
Net investment gains (losses)	946		2,858
Net investment gains (losses)	2,946	(23,884)	5,858	(37,390)
Other income (expense)	2,741	5,314	3,528	8,119
Net losses and loss adjustment expenses	(191,058)	(177,670)	(396,354)	(387,093)
Underwriting, policy acquisition and operating expenses	(76,976)	(76,648)	(144,764)	(147,247)
SPC U.S. federal income taxes expense	(994)	(349)	(1,526)	(991)
SPC dividend (expense) income	(3,747)	854	(5,689)	(1,513)
Interest expense	(5,502)	(4,919)	(10,965)	(9,360)
Income tax benefit (expense)	(2,927)	1,789	(755)	3,559
Segment results	8,627	(1,118)	1,453	(3,748)
Contingent Consideration Adjustment			(4,000)	0
Net income (loss)	10,627	(1,659)	4,453	(5,219)
Depreciation and amortization, net of accretion	5,954	10,059	13,631	20,409
Income tax expense (benefit)	2,927	(1,933)	755	(3,950)
NORCAL Group
Segment Reporting Information [Line Items]
Transaction-related costs		(700)		(1,900)
Income tax expense (benefit)		200		400
Specialty P&C
Segment Reporting Information [Line Items]
Net premiums earned	178,902	183,547	358,245	381,514
Workers' Compensation Insurance
Segment Reporting Information [Line Items]
Net premiums earned	41,018	41,709	81,821	82,393
Segregated Portfolio Cell Reinsurance
Segment Reporting Information [Line Items]
Net premiums earned	24,094	16,222	39,394	35,536
Lloyd's Syndicates
Segment Reporting Information [Line Items]
Net premiums earned	3,848	5,793	8,189	13,539
Operating segments | Specialty P&C
Segment Reporting Information [Line Items]
Net premiums earned	178,902	183,547	358,245	381,514
Net investment income	0	0	0	0
Equity in earnings (loss) of unconsolidated subsidiaries	0	0	0	0
Net investment gains (losses)	0		0
Net investment gains (losses)		0		0
Other income (expense)	1,021	1,903	2,014	2,924
Net losses and loss adjustment expenses	(145,044)	(137,002)	(309,096)	(302,960)
Underwriting, policy acquisition and operating expenses	(47,439)	(48,077)	(88,399)	(90,958)
SPC U.S. federal income taxes expense	0	0	0	0
SPC dividend (expense) income	0	0	0	0
Interest expense	0	0	0	0
Income tax benefit (expense)	0	0	0	0
Segment results	(12,560)	371	(37,236)	(9,480)
Depreciation and amortization, net of accretion	2,559	2,948	5,199	5,540
Operating segments | Workers' Compensation Insurance
Segment Reporting Information [Line Items]
Net premiums earned	41,018	41,709	81,821	82,393
Net investment income	0	0	0	0
Equity in earnings (loss) of unconsolidated subsidiaries	0	0	0	0
Net investment gains (losses)	0		0
Net investment gains (losses)		0		0
Other income (expense)	651	517	1,232	1,199
Net losses and loss adjustment expenses	(29,762)	(27,947)	(60,606)	(55,158)
Underwriting, policy acquisition and operating expenses	(14,400)	(13,669)	(27,379)	(26,669)
SPC U.S. federal income taxes expense	0	0	0	0
SPC dividend (expense) income	0	0	0	0
Interest expense	0	0	0	0
Income tax benefit (expense)	0	0	0	0
Segment results	(2,493)	610	(4,932)	1,765
Depreciation and amortization, net of accretion	854	874	1,723	1,748
Operating segments | Segregated Portfolio Cell Reinsurance
Segment Reporting Information [Line Items]
Net premiums earned	24,094	16,222	39,394	35,536
Net investment income	603	211	1,024	323
Equity in earnings (loss) of unconsolidated subsidiaries	0	0	0	0
Net investment gains (losses)	1,194		2,355
Net investment gains (losses)		(2,782)		(3,493)
Other income (expense)	1	1	1	1
Net losses and loss adjustment expenses	(13,816)	(9,272)	(22,238)	(20,763)
Underwriting, policy acquisition and operating expenses	(6,538)	(5,237)	(11,575)	(9,605)
SPC U.S. federal income taxes expense	(994)	(349)	(1,526)	(991)
SPC dividend (expense) income	(3,747)	854	(5,689)	(1,513)
Interest expense	0	0	0	0
Income tax benefit (expense)	0	0	0	0
Segment results	797	(352)	1,746	(505)
Depreciation and amortization, net of accretion	(552)	345	(488)	715
Operating segments | Lloyd's Syndicates
Segment Reporting Information [Line Items]
Net premiums earned	3,848	5,793	8,189	13,539
Net investment income	137	143	325	355
Equity in earnings (loss) of unconsolidated subsidiaries	0	0	0	0
Net investment gains (losses)	33		22
Net investment gains (losses)		(485)		(884)
Other income (expense)	5	129	2	263
Net losses and loss adjustment expenses	(2,436)	(3,449)	(4,414)	(8,212)
Underwriting, policy acquisition and operating expenses	(1,434)	(1,508)	(3,155)	(4,218)
SPC U.S. federal income taxes expense	0	0	0	0
SPC dividend (expense) income	0	0	0	0
Interest expense	0	0	0	0
Income tax benefit (expense)	0	0	0	0
Segment results	153	623	969	843
Depreciation and amortization, net of accretion	2	10	3	24
Operating segments | Corporate
Segment Reporting Information [Line Items]
Net premiums earned	0	0	0	0
Net investment income	30,910	21,590	60,611	41,709
Equity in earnings (loss) of unconsolidated subsidiaries	6,632	5,180	5,511	12,799
Net investment gains (losses)	(281)		481
Net investment gains (losses)		(20,617)		(33,013)
Other income (expense)	2,173	3,626	2,500	5,691
Net losses and loss adjustment expenses	0	0	0	0
Underwriting, policy acquisition and operating expenses	(8,275)	(9,019)	(16,477)	(17,756)
SPC U.S. federal income taxes expense	0	0	0	0
SPC dividend (expense) income	0	0	0	0
Interest expense	(5,502)	(4,919)	(10,965)	(9,360)
Income tax benefit (expense)	(2,927)	1,789	(755)	3,559
Segment results	22,730	(2,370)	40,906	3,629
Depreciation and amortization, net of accretion	3,091	5,882	7,194	12,382
Inter-segment Eliminations
Segment Reporting Information [Line Items]
Net premiums earned	0	0	0	0
Net investment income	0	0	0	0
Equity in earnings (loss) of unconsolidated subsidiaries	0	0	0	0
Net investment gains (losses)	0		0
Net investment gains (losses)		0		0
Other income (expense)	(1,110)	(862)	(2,221)	(1,959)
Net losses and loss adjustment expenses	0	0	0	0
Underwriting, policy acquisition and operating expenses	1,110	862	2,221	1,959
SPC U.S. federal income taxes expense	0	0	0	0
SPC dividend (expense) income	0	0	0	0
Interest expense	0	0	0	0
Income tax benefit (expense)	0	0	0	0
Segment results	0	0	0	0
Depreciation and amortization, net of accretion	0	0	0	0
Segment reconciling items
Segment Reporting Information [Line Items]
Transaction-related costs		$ (541)		$ (1,471)
Contingent Consideration Adjustment	$ 2,000		$ 3,000

Segment Information (Gross Prem

Segment Information (Gross Premiums Earned and Reconciliation to Net Premiums) (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]
Segment net premiums earned	$ 247,862	$ 247,271	$ 487,649	$ 512,982
Specialty P&C Segment
Segment Reporting Information [Line Items]
Ceded premiums earned	(26,567)	(18,308)	(46,231)	(32,620)
Segment net premiums earned	178,902	183,547	358,245	381,514
Specialty P&C Segment | HCPL
Segment Reporting Information [Line Items]
Gross premiums earned:	168,928	165,496	331,315	341,043
Specialty P&C Segment | Small Business Unit
Segment Reporting Information [Line Items]
Gross premiums earned:	25,931	26,188	52,005	52,726
Specialty P&C Segment | Medical Technology Liability
Segment Reporting Information [Line Items]
Gross premiums earned:	10,610	9,968	21,156	19,968
Specialty P&C Segment | Other
Segment Reporting Information [Line Items]
Gross premiums earned:	0	203	0	397
Workers' Compensation Insurance Segment
Segment Reporting Information [Line Items]
Ceded premiums earned	(21,126)	(21,812)	(41,489)	(42,162)
Segment net premiums earned	41,018	41,709	81,821	82,393
Workers' Compensation Insurance Segment | Traditional business
Segment Reporting Information [Line Items]
Gross premiums earned:	44,660	45,395	88,200	88,551
Workers' Compensation Insurance Segment | Alternative market business
Segment Reporting Information [Line Items]
Gross premiums earned:	17,484	18,126	35,110	36,004
Segregated Portfolio Cell Reinsurance Segment
Segment Reporting Information [Line Items]
Ceded premiums earned	(2,296)	(2,374)	(4,599)	(4,724)
Segment net premiums earned	24,094	16,222	39,394	35,536
Segregated Portfolio Cell Reinsurance Segment | HCPL
Segment Reporting Information [Line Items]
Gross premiums earned:	10,061	1,504	11,360	5,990
Segregated Portfolio Cell Reinsurance Segment | Workers' compensation
Segment Reporting Information [Line Items]
Gross premiums earned:	16,329	17,092	32,633	34,270
Lloyd's Syndicates Segment
Segment Reporting Information [Line Items]
Gross premiums earned:	4,522	6,443	9,568	15,675
Ceded premiums earned	(674)	(650)	(1,379)	(2,136)
Segment net premiums earned	$ 3,848	$ 5,793	$ 8,189	$ 13,539

Benefit Plans (Components of Ne

Benefit Plans (Components of Net Periodic Benefit Cost Credit) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plan, benefit basis, average of highest annual compensation period			5 years
Pension Plan
Components of net periodic benefit cost (income):
Interest cost	$ 914	$ 720	$ 1,818	$ 1,431
Expected return on Plan assets	(884)	(1,001)	(1,758)	(1,990)
Total net periodic benefit cost (income)	$ 30	$ (281)	$ 60	$ (559)