ProAssurance (PRA) 10-Q 7 Aug 19 2019 Q2 Quarterly report Financial data

COVER PAGE

COVER PAGE - shares	6 Months Ended
	Jun. 30, 2019	Jul. 31, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
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		53,760,019
Entity Central Index Key	0001127703
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investments
Fixed maturities, available for sale, at fair value; amortized cost, $2,188,547 and $2,116,825, respectively	$ 2,229,346	$ 2,093,798
Fixed maturities, trading, at fair value; cost, $42,905 and $38,445, respectively	43,156	38,188
Equity investments, at fair value; cost, $398,489 and $450,931, respectively	420,425	442,937
Short-term investments	287,009	308,319
Business owned life insurance	65,008	64,096
Investment in unconsolidated subsidiaries	385,631	367,757
Other investments, $33,824 and $31,344 at fair value, respectively, otherwise at cost or amortized cost	36,725	34,287
Total Investments	3,467,300	3,349,382
Cash and cash equivalents	91,879	80,471
Premiums receivable	278,828	261,466
Receivable from reinsurers on paid losses and loss adjustment expenses	17,418	11,558
Receivable from reinsurers on unpaid losses and loss adjustment expenses	352,012	343,820
Prepaid reinsurance premiums	48,392	40,631
Deferred policy acquisition costs	55,871	54,116
Deferred tax asset, net	11,290	29,108
Real estate, net	30,841	31,114
Operating lease ROU assets	20,374
Intangible assets, net	73,815	76,776
Goodwill	210,725	210,725
Other assets	127,373	111,559
Total Assets	4,786,118	4,600,726
Policy liabilities and accruals
Reserve for losses and loss adjustment expenses	2,195,460	2,119,847
Unearned premiums	441,923	415,211
Reinsurance premiums payable	54,891	55,614
Total Policy Liabilities	2,692,274	2,590,672
Operating lease liabilities	21,131
Other liabilities	203,940	199,295
Debt less debt issuance costs	287,217	287,757
Total Liabilities	3,204,562	3,077,724
Shareholders' Equity
Common shares, par value $0.01 per share, 100,000,000 shares authorized, 63,112,288 and 62,989,421 shares issued, respectively	631	630
Additional paid-in capital	385,200	384,713
Accumulated other comprehensive income (loss), net of deferred tax expense (benefit) of $8,627 and ($4,355), respectively	31,729	(16,911)
Retained earnings	1,581,273	1,571,847
Treasury shares, at cost, 9,352,373 shares as of each respective period end	(417,277)	(417,277)
Total Shareholders' Equity	1,581,556	1,523,002
Total Liabilities and Shareholders' Equity	$ 4,786,118	$ 4,600,726

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Available for sale securities, amortized cost	$ 2,188,547	$ 2,116,825
Trading securities, cost	42,905	38,445
Equity Investments, fair value, cost	398,489	450,931
Other investments, portion carried at fair value	$ 33,824	$ 31,344
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)	63,112,288	62,989,421
Deferred tax expense (benefit) on accumulated other comprehensive income (loss)	$ 8,627	$ (4,355)
Treasury shares, number of shares (in shares)	9,352,373	9,352,373

Condensed Consolidated Statemen

Condensed Consolidated Statements of Changes in Capital (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019	Jan. 01, 2018
Increase (Decrease) in Stockholders' Equity:
Beginning balance		$ 1,561,896	$ 1,569,169	$ 1,523,002	$ 1,594,795
Cumulative-effect adjustment adoption of ASU							$ 0
Common shares issued for compensation and effect of shares reissued to stock purchase plan		636	1,194	812	1,314
Share-based compensation		1,083	1,577	2,320	2,479
Net effect of restricted and performance shares issued		(13)	(20)	(2,644)	(3,869)
Dividends to shareholders		(16,656)	(17,630)	(33,316)	(34,246)
Other comprehensive income (loss)		23,074	(8,097)	48,640	(34,470)
Net income		11,536	28,423	43,186	40,279
Ending balance		1,581,556	1,574,616	1,581,556	1,574,616
Accounting Standards Update 2018-07
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU	[1]					$ (444)
Accounting Standards Update 2016-01
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU							8,334
Accounting Standards Update 2018-02
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU							0
Common Stock
Increase (Decrease) in Stockholders' Equity:
Beginning balance		631	630	630	628
Net effect of restricted and performance shares issued		0	0	1	2
Ending balance		631	630	631	630
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity:
Beginning balance		383,494	380,250	384,713	383,077
Common shares issued for compensation and effect of shares reissued to stock purchase plan		636	1,194	812	1,316
Share-based compensation		1,083	1,577	2,320	2,479
Net effect of restricted and performance shares issued		(13)	(20)	(2,645)	(3,871)
Ending balance		385,200	383,001	385,200	383,001
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity:
Beginning balance		8,655	(8,046)	(16,911)	14,911
Other comprehensive income (loss)		23,074	(8,097)	48,640	(34,470)
Ending balance		31,729	(16,143)	31,729	(16,143)
Accumulated Other Comprehensive Income (Loss) | Accounting Standards Update 2018-02
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU							3,416
Retained Earnings
Increase (Decrease) in Stockholders' Equity:
Beginning balance		1,586,393	1,614,344	1,571,847	1,614,186
Dividends to shareholders		(16,656)	(17,630)	(33,316)	(34,246)
Net income		11,536	28,423	43,186	40,279
Ending balance		1,581,273	1,625,137	1,581,273	1,625,137
Retained Earnings | Accounting Standards Update 2018-07
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU	[1]					$ (444)
Retained Earnings | Accounting Standards Update 2016-01
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU							8,334
Retained Earnings | Accounting Standards Update 2018-02
Increase (Decrease) in Stockholders' Equity:
Cumulative-effect adjustment adoption of ASU							$ (3,416)
Treasury Stock
Increase (Decrease) in Stockholders' Equity:
Beginning balance		(417,277)	(418,009)	(417,277)	(418,007)
Common shares issued for compensation and effect of shares reissued to stock purchase plan		0	0	0	(2)
Ending balance		$ (417,277)	$ (418,009)	$ (417,277)	$ (418,009)
[1]	See Note 1 for discussion of accounting guidance adopted during the period.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Income and Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues
Net premiums earned	$ 209,149	$ 223,591	$ 417,298	$ 410,750
Net investment income	23,539	22,384	46,357	44,411
Equity in earnings (loss) of unconsolidated subsidiaries	(5,152)	5,380	(5,962)	7,019
Net realized investment gains (losses):
OTTI losses	0	(404)	(136)	(404)
Portion of OTTI losses recognized in other comprehensive income before taxes	0	0	87	0
Net impairment losses recognized in earnings	0	(404)	(49)	(404)
Other net realized investment gains (losses)	9,308	3,199	45,980	(9,318)
Total net realized investment gains (losses)	9,308	2,795	45,931	(9,722)
Other income	2,777	2,044	4,872	4,767
Total revenues	239,621	256,194	508,496	457,225
Expenses
Net losses and loss adjustment expenses	168,440	161,728	328,195	291,515
Underwriting, policy acquisition and operating expenses
Operating expense	34,661	33,958	67,951	66,422
DPAC amortization	28,047	25,653	56,149	50,547
Segregated portfolio cells dividend expense (income)	(7,033)	2,785	(2,246)	4,532
Interest expense	4,247	3,958	8,576	7,663
Total expenses	228,362	228,082	458,625	420,679
Income before income taxes	11,259	28,112	49,871	36,546
Provision for income taxes
Current expense (benefit)	1,507	(1,175)	1,851	(2,503)
Deferred expense (benefit)	(1,784)	864	4,834	(1,230)
Total income tax expense (benefit)	(277)	(311)	6,685	(3,733)
Net income	11,536	28,423	43,186	40,279
Other comprehensive income (loss), after tax, net of reclassification adjustments	23,074	(8,097)	48,640	(34,470)
Comprehensive income (loss)	$ 34,610	$ 20,326	$ 91,826	$ 5,809
Earnings per share
Basic (in usd per share)	$ 0.21	$ 0.53	$ 0.80	$ 0.75
Diluted (in usd per share)	$ 0.21	$ 0.53	$ 0.80	$ 0.75
Weighted average number of common shares outstanding:
Basic (in shares)	53,750	53,610	53,716	53,567
Diluted (in shares)	53,828	53,741	53,818	53,716
Cash dividends declared per common share (in usd per share)	$ 0.31	$ 0.31	$ 0.62	$ 0.62

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) $ in Thousands, £ in Millions	6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)
Operating Activities
Net income	$ 43,186	$ 40,279
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, net of accretion	9,653	11,036
(Increase) decrease in cash surrender value of BOLI	(912)	(904)
Net realized investment (gains) losses	(45,931)	9,722
Share-based compensation	2,320	2,517
Deferred income tax expense (benefit)	4,834	(1,230)
Policy acquisition costs, net of amortization (net deferral)	(1,755)	(1,932)
Equity in (earnings) loss of unconsolidated subsidiaries	5,962	(7,019)
Distributed earnings from unconsolidated subsidiaries	7,298	4,595
Other	1,643	796
Other changes in assets and liabilities:
Premiums receivable	(17,362)	(41,560)
Reinsurance related assets and liabilities	(22,536)	11,980
Other assets	(2,557)	969
Reserve for losses and loss adjustment expenses	75,613	30,436
Unearned premiums	26,712	22,181
Other liabilities	(7,153)	(16,300)
Net cash provided (used) by operating activities	79,015	65,566
Purchases of:
Fixed maturities, available for sale	(350,937)	(552,451)
Fixed maturities, trading	(4,486)	(29,999)
Equity investments	(38,959)	(91,054)
Other investments	(13,769)	(15,228)
Funding of qualified affordable housing project tax credit partnerships	(322)	(74)
Investment in unconsolidated subsidiaries	(41,947)	(27,734)
Proceeds from sales or maturities of:
Fixed maturities, available for sale	277,592	658,337
Equity investments	102,410	75,376
Other investments	14,715	14,725
Return of invested capital from unconsolidated subsidiaries	10,800	36,154
Net sales or maturities (purchases) of short-term investments	21,623	219,053
Unsettled security transactions, net change	(4,171)	(3,044)
Purchases of capital assets	(5,042)	(5,113)
Repayments (advances) under Syndicate Credit Agreement	29,790	(1,050)
Other	(17)	0
Net cash provided (used) by investing activities	(2,720)	277,898
Financing Activities
Repayments under Revolving Credit Agreement	0	(123,000)
Repayments of Mortgage Loans	(724)	(698)
Dividends to shareholders	(59,956)	(283,313)
Capital contribution received from (return of capital to) external segregated portfolio cell participants	(1,544)	(329)
Other	(2,663)	(3,904)
Net cash provided (used) by financing activities	(64,887)	(411,244)
Increase (decrease) in cash and cash equivalents	11,408	(67,780)
Cash and cash equivalents at beginning of period	80,471	134,495
Cash and cash equivalents at end of period	91,879	66,715
Significant Non-Cash Transactions
Dividends declared and not yet paid	16,656	17,630
Operating ROU assets obtained in exchange for operating lease liabilities	$ 3,729	$ 0

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2019
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 and its consolidated subsidiaries (ProAssurance, PRA or the Company). 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, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 . The accompanying Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and Notes contained in ProAssurance’s December 31, 2018 report on Form 10-K. In connection with its preparation of the Condensed Consolidated Financial Statements, ProAssurance evaluated events that occurred subsequent to June 30, 2019 for recognition or disclosure in its financial statements and notes to financial statements. Beginning in the third quarter of 2018, 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 14 . Reclassifications As a result of the third quarter of 2018 segment reorganization, prior period segment information in Note 14 has been recast to conform to the Company's current segment reporting (see Note 14 for further information). Accounting Policies Except as added 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, 2018 report on Form 10-K. Leases ProAssurance is involved in a number of leases, primarily for office facilities. The Company determines if an arrangement is a lease at the inception date of the contract and classifies all leases as either financing or operating. Operating leases are included in operating lease ROU assets and operating lease liabilities on the Condensed Consolidated Balance Sheet as of June 30, 2019 . The ROU asset represents the right to use the underlying asset for the lease term. As of June 30, 2019 , ProAssurance has no leases that are classified as financing leases. Operating ROU assets and operating lease liabilities are initially recognized as of the lease commencement date based on the present value of the remaining lease payments, discounted over the term of the lease using a discount rate determined based on information available as of the commencement date. As the majority of ProAssurance's lessors do not provide an implicit discount rate, the Company uses its collateralized incremental borrowing rate in determining the present value of remaining lease payments. Due to the adoption of ASU 2016-02 (see further discussion that follows), the Company used its collateralized incremental borrowing rate as of January 1, 2019 for operating leases that commenced prior to that date. Subsequent to the initial recognition, the operating ROU asset is amortized over the lease term on a straight-line basis as operating lease expense which 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, 2019 and 2018. Leases with an initial term of twelve months or less are considered short-term and are not recorded on the Condensed Consolidated Balance Sheet; lease expense for these leases is also recognized on a straight-line basis over the lease term. Additionally, for leases entered into or reassessed after the adoption of ASU 2016-02, ProAssurance accounts for lease and non-lease components of a contract as a single lease component. Operating lease ROU assets are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The carrying amount of a ROU asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use of the underlying leased asset over the remaining lease term. That assessment is based on the carrying amount of the ROU asset at the date it is tested for recoverability and an impairment loss is measured and recognized as the amount by which the carrying amount of the ROU asset exceeds its fair value. Other Liabilities Other liabilities consisted of the following: (In thousands) June 30, 2019 December 31, 2018 SPC dividends payable $ 51,952 $ 53,604 Unpaid shareholder dividends 16,656 43,446 All other 135,332 102,245 Total other liabilities $ 203,940 $ 199,295 SPC dividends payable are the cumulative undistributed earnings contractually payable to the external cell participants of SPC s operated by ProAssurance's Cayman Islands subsidiaries, Inova Re and Eastern Re . Unpaid dividends represent common stock dividends declared by ProAssurance's Board that had not yet been paid as of June 30, 2019 . Unpaid dividends at December 31, 2018 included a special dividend declared in the fourth quarter of 2018 that was paid in January 2019 . Accounting Changes Adopted Leases ( ASU 2016-02) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance that requires a lessee to recognize for all leases (with the exception of short-term leases) a lease liability, which is a lessee's obligation to make lease payments arising from a lease, measured on a discounted basis, and a right-of-use asset, which is an asset that represents the lessee's right to use, or control the use of, a specified asset for the lease term. ProAssurance adopted the guidance as of January 1, 2019 using a modified retrospective application and elected the transition option provided that allows companies to continue to apply legacy GAAP in comparative periods. Also, ProAssurance elected the package of practical expedients permitted under the guidance, which allowed the Company to carryforward its historical lease classification, its assessment on whether a contract is or contains a lease and its initial direct costs for any leases that existed prior to adoption of the new standard. Furthermore, ProAssurance elected to combine lease and non-lease components and to keep leases with an initial term of 12 months or less off the Condensed Consolidated Balance Sheet and recognize the associated lease payments in the Condensed Consolidated Statements of Income and Comprehensive Income on a straight-line basis over the lease term. ProAssurance recognized total ROU assets and total lease liabilities of approximately $19 million on the Condensed Consolidated Balance Sheet as of January 1, 2019 which relate to ProAssurance's real estate operating leases; the Company does not consider these leases to be material to its financial position. Adoption of this guidance had no material impact on ProAssurance's results of operation or cash flows. ProAssurance's Revolving Credit Agreement contains a financial covenant regarding permitted leverage ratios based upon Consolidated Funded Indebtedness to Consolidated Total Capitalization; however, adoption of this guidance had no material impact on this covenant. ProAssurance’s Mortgage Loans also contain a financial covenant regarding permitted leverage ratios, principally based upon SAP Consolidated Net Worth; however, as the NAIC did not adopt the principles found in ASU 2016-02, adoption of the guidance had no impact on this covenant. Premium Amortization on Purchased Callable Debt Securities ( ASU 2017-08) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance that will require the premium for certain callable debt securities to be amortized over a shorter period than is currently required. Currently amortization is permitted over the contractual life of the instrument and the guidance shortens the amortization to the earliest call date. The purpose of the guidance is to more closely align the amortization period of premiums to expectations incorporated in market pricing on the underlying securities. ProAssurance adopted the guidance as of January 1, 2019. As ProAssurance amortizes premium on callable debt securities to the earliest call date, adoption of the guidance had no material effect on ProAssurance’s results of operations, financial position or cash flows. Derivatives and Hedging ( ASU 2017-12) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance to improve financial reporting of hedging relationships to better portray the entity's risk management activities in the consolidated financial statements. The new guidance eliminates the requirement to separately measure and report hedge ineffectiveness and requires the entire change in the fair value of a hedging instrument to be presented in the same income statement line as the hedged item. ProAssurance adopted the guidance as of January 1, 2019. ProAssurance's derivative instrument at June 30, 2019 is not designated as a hedging instrument; therefore, adoption had no effect on ProAssurance's results of operations, financial position or cash flows. Improvements to Nonemployee Share-Based Payment Accounting ( ASU 2018-07) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance which reduces the complexity in accounting for nonemployee share-based payment awards. The new guidance substantially aligns the accounting for nonemployee share-based payment awards with the accounting guidance for employee share-based payment awards with certain exceptions, including the inputs used in estimating the fair value of the nonemployee awards and the period of time and pattern of expense recognition. ProAssurance adopted the guidance as of January 1, 2019 using a modified retrospective application and recorded a cumulative-effect adjustment of approximately $0.4 million to beginning retained earnings in the Condensed Consolidated Statement of Changes in Capital for the six months ended June 30, 2019 . Adoption had no material effect of ProAssurance's results of operations or cash flows. Derivatives and Hedging - Inclusion of the Secured Overnight Financing Rate (SOFR) Overnight Index Swap as a Benchmark Interest Rate for Hedge Accounting Purposes (ASU 2018-16) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued new guidance that permits the use of the Overnight Index Swap Rate based on the Secured Financing Rate as a U.S. benchmark interest rate for hedge accounting purposes. ProAssurance adopted the guidance as of January 1, 2019. As of June 30, 2019 , ProAssurance's derivative instrument is not designated as a hedging instrument; therefore, adoption had no effect on ProAssurance's results of operations, financial position or cash flows. Accounting Changes Not Yet Adopted Improvements to Financial Instruments - Credit Losses ( ASU 2016-13) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued guidance that replaces the incurred loss impairment methodology, which delays recognition of credit losses until a probable loss has been incurred, with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. Under the new guidance, credit losses are required to be recorded through an allowance for credit losses account and the income statement will reflect the initial recognition of lifetime expected credit losses for any newly recognized financial assets as well as increases or decreases of expected credit losses that have taken place during the period. Credit losses on available-for-sale fixed maturity securities will be required to be presented as an allowance, rather than as a write-down of the asset, limited to the amount by which the fair value is below amortized cost. Adoption of this guidance is not expected to have a material impact on ProAssurance's available-for-sale fixed maturity portfolio. In addition, ProAssurance's premiums receivable and receivables from reinsurers are also included in the scope of this new guidance; however, ProAssurance has not historically experienced material credit losses due to the financial condition of an insured or reinsurer. ProAssurance plans to adopt the guidance beginning January 1, 2020 and is in the process of evaluating the effect the new guidance would have on its results of operations and financial position. Simplifying the Test for Goodwill Impairment ( ASU 2017-04) Effective for the fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued guidance that simplifies the requirements to test goodwill for impairment for business entities that have goodwill reported in their financial statements. The guidance eliminates the second step of the impairment test which measures a goodwill impairment loss by comparing the implied fair value of a reporting unit's goodwill with the carrying amount. In addition, the guidance also eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment. ProAssurance plans to adopt the guidance beginning January 1, 2020. Adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Changes to the Disclosure Requirements for Fair Value Measurement ( ASU 2018-13) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued guidance that eliminates, modifies and adds certain disclosure requirements related to fair value measurements. The new guidance eliminates the requirements to disclose the transfers between Level 1 and Level 2 of the fair value hierarchy, the policy for the timing of transfers between levels of the fair value hierarchy and the valuation process for Level 3 fair value measurements while it modifies existing disclosure requirements related to measurement uncertainty and the requirement to disclose the timing of liquidation of an investee's assets for investments in certain entities that calculate NAV . The new guidance also adds requirements to disclose changes in unrealized gains and losses included in OCI for recurring Level 3 fair value measurements as well as the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. An entity is permitted to early adopt any eliminated or modified disclosure requirements and delay adoption of the additional disclosure requirements until the guidance is effective. During the third quarter of 2018, ProAssurance elected to early adopt the provisions that eliminate and modify certain disclosure requirements within Note 2 on a retrospective basis and adoption of these certain provisions had no material effect on ProAssurance’s results of operations, financial position or cash flows as it affected disclosures only. ProAssurance plans to adopt the additional disclosure requirements beginning January 1, 2020 and adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Intangibles - Goodwill and Other-Internal-Use Software ( ASU 2018-15) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB amended the new standard regarding accounting for implementation costs in cloud computing arrangements. The amended guidance substantially aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. ProAssurance plans to adopt the guidance beginning January 1, 2020. Adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Targeted Improvements to Related Party Guidance for VIEs ( ASU 2018-17) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB amended guidance which improves the consistency of the application of the VIE guidance for common control arrangements. The amended guidance requires an entity to consider indirect interests held through related parties under common control on a proportional basis rather than as the equivalent of a direct interest in its entirety when determining whether a decision-making fee is a variable interest. ProAssurance plans to adopt the guidance beginning January 1, 2020. As of June 30, 2019 ProAssurance does not have any material indirect interests held through related parties under common control; therefore, adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Collaborative Arrangements ( ASU 2018-18) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued new guidance which clarifies how to assess whether certain transactions between participants in a collaborative arrangement should be accounted for under the revenue from contracts with customers accounting standard when the counterpart is a customer. In addition, the guidance precludes an entity from presenting consideration from a transaction in a collaborative arrangement as revenue from contracts with customers if the counterparty is not a customer for that transaction. ProAssurance plans to adopt the guidance beginning January 1, 2020 and adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows.

Fair Value Measurement

Fair Value Measurement	6 Months Ended
	Jun. 30, 2019
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 debt or equity 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, 2019 and December 31, 2018 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. June 30, 2019 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 $ — $ 110,449 $ — $ 110,449 U.S. Government-sponsored enterprise obligations — 29,147 — 29,147 State and municipal bonds — 290,243 — 290,243 Corporate debt, multiple observable inputs — 1,304,560 — 1,304,560 Corporate debt, limited observable inputs — — 2,304 2,304 Residential mortgage-backed securities — 182,258 — 182,258 Agency commercial mortgage-backed securities — 11,475 — 11,475 Other commercial mortgage-backed securities — 62,769 1,171 63,940 Other asset-backed securities — 231,978 2,992 234,970 Fixed maturities, trading — 43,156 — 43,156 Equity investments Financial 58,517 — — 58,517 Utilities/Energy 42,788 — — 42,788 Consumer oriented 40,588 — — 40,588 Industrial 39,186 — — 39,186 Bond funds 174,795 — — 174,795 All other 43,268 — — 43,268 Short-term investments 243,908 43,101 — 287,009 Other investments — 33,200 624 33,824 Other assets — 1,085 — 1,085 Total assets categorized within the fair value hierarchy $ 643,050 $ 2,343,421 $ 7,091 2,993,562 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Equity investments 21,283 Investment in unconsolidated subsidiaries 291,000 Total assets at fair value $ 3,305,845 December 31, 2018 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 $ — $ 120,201 $ — $ 120,201 U.S. Government-sponsored enterprise obligations — 35,354 — 35,354 State and municipal bonds — 293,772 — 293,772 Corporate debt, multiple observable inputs 2,319 1,216,834 — 1,219,153 Corporate debt, limited observable inputs — — 4,322 4,322 Residential mortgage-backed securities — 181,238 — 181,238 Agency commercial mortgage-backed securities — 13,108 — 13,108 Other commercial mortgage-backed securities — 30,993 — 30,993 Other asset-backed securities — 191,807 3,850 195,657 Fixed maturities, trading — 38,188 — 38,188 Equity investments Financial 62,344 — — 62,344 Utilities/Energy 46,533 — — 46,533 Consumer oriented 47,462 — — 47,462 Industrial 41,487 — — 41,487 Bond funds 174,753 — — 174,753 All other 50,066 — — 50,066 Short-term investments 265,910 42,409 — 308,319 Other investments — 31,341 3 31,344 Other assets — 1,884 — 1,884 Total assets categorized within the fair value hierarchy $ 690,874 $ 2,197,129 $ 8,175 2,896,178 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Equity investments 20,292 Investment in unconsolidated subsidiaries 268,436 Total assets at fair value $ 3,184,906 The fair values for securities included in the Level 2 category, with the few exceptions described below, were developed by one of several third party, nationally recognized pricing services, including services that price only certain types of securities. Each service uses complex methodologies to determine values for securities and subject the values they develop to quality control reviews. Management selected a primary source for each type of security in the portfolio and reviewed the values provided for reasonableness by comparing data to alternate pricing services and to available market and trade data. Values that appeared inconsistent were further reviewed for appropriateness. Any value that did not appear reasonable was discussed with the service that provided the value and adjusted, if necessary. There were no material changes to the values supplied by the pricing services during the three and six months ended June 30, 2019 . Level 2 Valuations Below is a summary description of the valuation methodologies primarily used by the pricing services for securities in the Level 2 category, by security type: U.S. Treasury obligations were valued based on quoted prices for identical assets, or, in markets that are not active, quotes for similar assets, taking into consideration adjustments for variations in contractual cash flows and yields to maturity. U.S. Government-sponsored enterprise obligations were valued using pricing models that consider current and historical market data, normal trading conventions, credit ratings, and the particular structure and characteristics of the security being valued, such as yield to maturity, redemption options, and contractual cash flows. Adjustments to model inputs or model results were included in the valuation process when necessary to reflect recent regulatory, government or corporate actions or significant economic, industry or geographic events affecting the security’s fair value. State and municipal bonds were valued using a series of matrices that considered credit ratings, the structure of the security, the sector in which the security falls, yields, and contractual cash flows. Valuations were further adjusted, when necessary, to reflect the expected effect on fair value of recent significant economic or geographic events or ratings changes. Corporate debt, multiple observable inputs consisted primarily of corporate bonds, but also included a small number of bank loans. The methodology used to value Level 2 corporate bonds was the same as the methodology previously described for U.S. Government-sponsored enterprise obligations. Bank loans were valued based on an average of broker quotes for the loans in question, if available. If quotes were not available, the loans were valued based on quoted prices for comparable loans or, if the loan was newly issued, by comparison to similar seasoned issues. Broker quotes were compared to actual trade prices to permit assessment of the reliability of the quotes; unreliable quotes were not considered in quoted averages. Residential and commercial mortgage-backed securities were valued using a pricing matrix which considers the issuer type, coupon rate and longest cash flows outstanding. The matrix used was based on the most recently available market information. Agency and non-agency collateralized mortgage obligations were both valued using models that consider the structure of the security, current and historical information regarding prepayment speeds, ratings and ratings updates, and current and historical interest rate and interest rate spread data. Other asset-backed securities were valued using models that consider the structure of the security, monthly payment information, current and historical information regarding prepayment speeds, ratings and ratings updates, and current and historical interest rate and interest rate spread data. Spreads and prepayment speeds consider collateral type. Fixed maturities, trading , are held by the Lloyd's Syndicates segment and include U.S. Treasury obligations, U.S. Government-sponsored enterprise obligations, corporate debt with multiple observable inputs and other asset-backed securities. These securities were valued using the respective valuation methodologies discussed above for each security type. Short-term investments were securities maturing within one year, carried at fair value which approximated the cost of the securities due to their short-term nature. Other investments consisted primarily of convertible bonds valued using a pricing model that incorporated selected dealer quotes as well as current market data regarding equity prices and risk free rates. If dealer quotes were unavailable for the security being valued, quotes for securities with similar terms and credit status were used in the pricing model. Dealer quotes selected for use were those considered most accurate based on parameters such as underwriter status and historical reliability. Other assets consisted of an interest rate cap derivative instrument, which is discussed in Note 10 , valued using a model which considers the volatilities from other instruments with similar maturities, strike prices, durations and forward yield curves. Level 3 Valuations Below is a summary description of the valuation methodologies used as well as quantitative information regarding securities in the Level 3 category, by security type: Level 3 Valuation Methodologies Corporate debt, limited observable inputs consisted of corporate bonds valued using dealer quotes for similar securities or discounted cash flow models using yields currently available for similar securities. Similar securities are defined as securities of comparable credit quality that have like terms and payment features. Assessments of credit quality were based on NRSRO ratings, if available, or were subjectively determined by management if not available. At June 30, 2019 , 100% of the securities were rated and the average rating was AA- . At December 31, 2018 , 54% of the securities were rated and the average rating was BBB+ . Other commercial mortgage-backed and other asset-backed securities consisted of securitizations of receivables valued using dealer quotes for similar securities or discounted cash flow models using yields currently available for similar securities. Similar securities are defined as securities of comparable credit quality that have like terms and payment features. Assessments of credit quality were based on NRSRO ratings, if available, or were subjectively determined by management if not available. At June 30, 2019 , 28% of the securities were rated and the average rating was A- . At December 31, 2018 , 25% of the securities were rated and the average rating was AAA . Other investments consisted of convertible securities for which limited observable inputs were available at June 30, 2019 and December 31, 2018 . The securities were valued internally based on expected cash flows, including the expected final recovery, discounted at a yield that considered the lack of liquidity and the financial status of the issuer. Quantitative Information Regarding Level 3 Valuations Fair Value at ($ in thousands) June 30, 2019 December 31, 2018 Valuation Technique Unobservable Input Range Assets: Corporate debt, limited observable inputs $2,304 $4,322 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other commercial mortgage-backed securities $1,171 — Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other asset-backed securities $2,992 $3,850 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other investments $624 $3 Discounted Cash Flows Comparability Adjustment 0% - 10% (5%) 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 The following tables (the Level 3 Tables) present summary information regarding changes in the fair value of assets measured at fair value using Level 3 inputs. June 30, 2019 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance March 31, 2019 $ 4,296 $ 4,132 $ 3 $ 8,431 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income — (22 ) — (22 ) Net realized investment gains (losses) — — 33 33 Included in other comprehensive income 8 53 — 61 Purchases — — 170 170 Sales (2,000 ) — — (2,000 ) Transfers in — — 418 418 Transfers out — — — — Balance June 30, 2019 $ 2,304 $ 4,163 $ 624 $ 7,091 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — June 30, 2019 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance December 31, 2018 $ 4,322 $ 3,850 $ 3 $ 8,175 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income 2 (140 ) — (138 ) Net realized investment gains (losses) — — 33 33 Included in other comprehensive income 11 210 — 221 Purchases 1,305 — 170 1,475 Sales (2,136 ) (6 ) — (2,142 ) Transfers in — 1,200 418 1,618 Transfers out (1,200 ) (951 ) — (2,151 ) Balance June 30, 2019 $ 2,304 $ 4,163 $ 624 $ 7,091 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — June 30, 2018 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance March 31, 2018 $ 15,097 $ 17,323 $ 365 $ 32,785 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (36 ) 1 — (35 ) Net realized investment gains (losses) (8 ) — 6 (2 ) Included in other comprehensive income (90 ) (111 ) — (201 ) Purchases — 3,225 — 3,225 Sales (1,644 ) (158 ) (366 ) (2,168 ) Transfers in 558 — — 558 Transfers out (5,497 ) (10,860 ) — (16,357 ) Balance June 30, 2018 $ 8,380 $ 9,420 $ 5 $ 17,805 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — June 30, 2018 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance December 31, 2017 $ 13,703 $ 4,986 $ 409 $ 19,098 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (74 ) 1 — (73 ) Net realized investment gains (losses) (8 ) — (38 ) (46 ) Included in other comprehensive income (128 ) (141 ) — (269 ) Purchases 6,005 16,678 — 22,683 Sales (4,549 ) (185 ) (366 ) (5,100 ) Transfers in 2,627 — — 2,627 Transfers out (9,196 ) (11,919 ) — (21,115 ) Balance June 30, 2018 $ 8,380 $ 9,420 $ 5 $ 17,805 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — Transfers Transfers shown in the preceding Level 3 tables were as of the end of the quarter in which the transfer occurred. All transfers were to or from Level 2. All transfers during the three and six months ended June 30, 2019 and 2018 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, 2019 and December 31, 2018 , certain LP s/ LLC s 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, 2019 and fair values of these investments as of June 30, 2019 and December 31, 2018 was as follows: Unfunded Fair Value (In thousands) June 30, June 30, December 31, Equity investments: Mortgage fund (1) None $ 21,283 $ 20,292 Investment in unconsolidated subsidiaries: Private debt funds (2) $18,333 14,032 18,196 Long equity fund (3) None 6,511 6,561 Long/short equity funds (4) None 29,066 28,805 Non-public equity funds (5) $82,544 122,411 114,811 Multi-strategy fund of funds (6) None 9,596 9,322 Credit funds (7) $2,971 40,838 29,164 Long/short commodities fund (8) None 14,287 12,958 Strategy focused funds (9) $48,228 54,259 48,619 291,000 268,436 Total investments carried at NAV $ 312,283 $ 288,728 Below is additional information regarding each of the investments listed in the table above as of June 30, 2019 . (1) This investment fund is focused on the structured mortgage market. The fund will primarily invest in U.S. Agency mortgage-backed securities. Redemptions are allowed at the end of any calendar quarter with a prior notice requirement of 65 days and are paid within 45 days at the end of the redemption dealing day. (2) This investment is comprised of interests in three 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; the other two do not permit redemption. Income and capital are to be periodically distributed at the discretion of the LP s over an anticipated time frame that spans from three to eight years . (3) This fund is a LP that holds long equities of public international companies. Redemptions are allowed at the end of any calendar month with a prior notice requirement of 15 days and are paid within 10 days of the end of the calendar month of the redemption request. (4) This investment is comprised of interests in multiple unrelated LP funds. The funds hold primarily long and short North American equities and target absolute returns using strategies designed to take advantage of market opportunities. The funds generally permit quarterly or semi-annual capital redemptions subject to notice requirements of 30 to 90 days . For some funds, redemptions above specified thresholds (lowest threshold is 90% ) may be only partially payable until after a fund audit is completed and are then payable within 30 days . (5) 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 LP s. Two of the LP s 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 . (6) This fund is a LLC structured to build and manage low volatility, multi-manager portfolios that have little or no correlation to the broader fixed income and equity security markets. Redemptions are not permitted but offers to repurchase units of the LLC may be extended periodically. (7) This investment is comprised of four 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. A third fund focuses on private middle market company mezzanine loans, while the remaining fund seeks event driven opportunities across the corporate credit spectrum. Two funds are allowed redemptions at any quarter-end with a prior notice requirement of 90 days , one fund permits redemption at any quarter-end with a prior notice requirement of 180 days and one fund does not allow redemptions. (8) This fund is a LLC invested across a broad range of commodities and focuses primarily on market neutral, relative value strategies, seeking to generate absolute returns with low correlation to broad commodity, equity and fixed income markets. Following an initial one-year lock-up period, redemptions are allowed with a prior notice requirement of 30 days and are payable within 30 days . (9) This investment is comprised of multiple unrelated LP s/ LLC s funds. One fund is a 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. Another fund is a LP focused on North American energy infrastructure assets that allows redemption with consent of the General Partner. The remaining funds are real estate focused LP s, one of which allows for redemption with prior notice. ProAssurance may not sell, transfer or assign its interest in any of the above LP s/ LLC s without special consent from the LP s/ LLC s. Nonrecurring Fair Value Measurement At June 30, 2019 and December 31, 2018 , ProAssurance did no t have any assets or liabilities that were measured at fair value on a nonrecurring basis. 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. All fair values provided primarily fall within the Level 3 fair value category. June 30, 2019 December 31, 2018 (In thousands) Carrying Fair Carrying Fair Financial assets: BOLI $ 65,008 $ 65,008 $ 64,096 $ 64,096 Other investments $ 2,901 $ 2,902 $ 2,943 $ 2,943 Other assets $ 27,324 $ 27,323 $ 35,921 $ 35,468 Financial liabilities: Senior notes due 2023* $ 250,000 $ 272,115 $ 250,000 $ 264,810 Mortgage Loans* $ 38,340 $ 38,340 $ 39,064 $ 39,064 Other liabilities $ 41,095 $ 41,095 $ 21,300 $ 21,300 * Carrying value excludes 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. Two 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 $25.0 million and $24.1 million at June 30, 2019 and December 31, 2018 , respectively. The deferred compensation liabilities are adjusted to match the fair value of the deferred compensation assets. Other assets also included a secured note receivable and unsecured note receivable under two separate line of credit agreements. Fair value of these notes receivable was based on the present value of expected cash flows from the notes receivable, discounted at market rates on the valuation date for receivables with similar credit standings and similar payment structures. The fair value of the debt 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, 2019
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Available-for-sale fixed maturities at June 30, 2019 and December 31, 2018 included the following: June 30, 2019 (In thousands) Amortized Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available for sale U.S. Treasury obligations $ 108,961 $ 1,655 $ 167 $ 110,449 U.S. Government-sponsored enterprise obligations 29,035 141 29 29,147 State and municipal bonds 279,664 10,591 12 290,243 Corporate debt 1,283,074 26,112 2,322 1,306,864 Residential mortgage-backed securities 181,183 2,140 1,065 182,258 Agency commercial mortgage-backed securities 11,271 224 20 11,475 Other commercial mortgage-backed securities 62,593 1,381 34 63,940 Other asset-backed securities 232,766 2,292 88 234,970 $ 2,188,547 $ 44,536 $ 3,737 $ 2,229,346 December 31, 2018 (In thousands) Amortized Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available for sale U.S. Treasury obligations $ 121,274 $ 331 $ 1,404 $ 120,201 U.S. Government-sponsored enterprise obligations 35,758 25 429 35,354 State and municipal bonds 289,544 4,877 649 293,772 Corporate debt 1,244,577 3,328 24,430 1,223,475 Residential mortgage-backed securities 184,463 814 4,039 181,238 Agency commercial mortgage-backed securities 13,296 12 200 13,108 Other commercial mortgage-backed securities 31,330 38 375 30,993 Other asset-backed securities 196,583 254 1,180 195,657 $ 2,116,825 $ 9,679 $ 32,706 $ 2,093,798 The recorded cost basis and estimated fair value of available-for-sale fixed maturities at June 30, 2019 , 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 $ 108,961 $ 16,545 $ 71,405 $ 22,076 $ 423 $ 110,449 U.S. Government-sponsored enterprise obligations 29,035 5,391 6,005 17,608 143 29,147 State and municipal bonds 279,664 14,647 116,908 133,199 25,489 290,243 Corporate debt 1,283,074 154,196 782,386 343,561 26,721 1,306,864 Residential mortgage-backed securities 181,183 182,258 Agency commercial mortgage-backed securities 11,271 11,475 Other commercial mortgage-backed securities 62,593 63,940 Other asset-backed securities 232,766 234,970 $ 2,188,547 $ 2,229,346 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, 2019 . Cash and securities with a carrying value of $45.2 million at June 30, 2019 were on deposit with various state insurance departments to meet regulatory requirements. As a member of Lloyd's and a capital provider to Syndicate 1729 and Syndicate 6131 , ProAssurance is required to maintain capital at Lloyd's , referred to as FAL . ProAssurance's FAL investments at June 30, 2019 included available-for-sale fixed maturities with a fair value of $129.6 million and short-term investments with a fair value of approximately $5.2 million on deposit with Lloyd's in order to satisfy these FAL requirements. 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, 2019 and December 31, 2018 , including the length of time the investment had been held in a continuous unrealized loss position. June 30, 2019 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 $ 34,577 $ 167 $ 2,006 $ 12 $ 32,571 $ 155 U.S. Government-sponsored enterprise obligations 9,372 29 1,986 14 7,386 15 State and municipal bonds 4,589 12 2,663 7 1,926 5 Corporate debt 242,882 2,322 46,959 514 195,923 1,808 Residential mortgage-backed securities 81,377 1,065 1,166 1 80,211 1,064 Agency commercial mortgage-backed securities 317 20 — — 317 20 Other commercial mortgage-backed securities 4,163 34 — — 4,163 34 Other asset-backed securities 42,436 88 4,660 1 37,776 87 $ 419,713 $ 3,737 $ 59,440 $ 549 $ 360,273 $ 3,188 December 31, 2018 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 $ 97,969 $ 1,405 $ 20,221 $ 119 $ 77,748 $ 1,286 U.S. Government-sponsored enterprise obligations 33,677 429 20,479 126 13,198 303 State and municipal bonds 63,094 648 30,924 143 32,170 505 Corporate debt 938,651 24,429 447,891 8,804 490,760 15,625 Residential mortgage-backed securities 157,120 4,039 27,311 209 129,809 3,830 Agency commercial mortgage-backed securities 9,822 200 4,566 22 5,256 178 Other commercial mortgage-backed securities 22,924 375 13,348 164 9,576 211 Other asset-backed securities 142,470 1,181 70,218 236 72,252 945 $ 1,465,727 $ 32,706 $ 634,958 $ 9,823 $ 830,769 $ 22,883 As of June 30, 2019 , excluding U.S. Government or U.S. Government-sponsored enterprise obligations, there were 328 debt securities ( 15.5% of all available-for-sale fixed maturity securities held) in an unrealized loss position representing 248 issuers. The greatest and second greatest unrealized loss positions among those securities were each approximately $0.2 million . The securities were evaluated for OTTI as of June 30, 2019 . As of December 31, 2018 , excluding U.S. Government or U.S. Government-sponsored enterprise obligations, there were 1,044 debt securities ( 50.6% of all available-for-sale fixed maturity securities held) in an unrealized loss position representing 550 issuers. The greatest and second greatest unrealized loss positions among those securities were approximately $0.6 million and $0.5 million , respectively. The securities were evaluated for OTTI as of December 31, 2018 . 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 OTTI . A detailed discussion of the factors considered in the assessment is included in Note 1 of the Notes to Consolidated Financial Statements included in ProAssurance's December 31, 2018 Form 10-K. Fixed maturity securities held in an unrealized loss position at June 30, 2019 , excluding asset-backed securities, have paid all scheduled contractual payments and are expected to continue doing so. 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, 2019 OTTI 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. 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) 2019 2018 2019 2018 Proceeds from sales (exclusive of maturities and paydowns) $ 61.8 $ 115.8 $ 93.3 $ 495.0 Purchases $ 171.8 $ 184.6 $ 350.9 $ 552.5 Equity Investments ProAssurance's equity investments are carried at fair value with changes in fair value recognized in income as a component of net realized investment gains (losses) during the period of change. Equity investments on the Condensed Consolidated Balance Sheets as of June 30, 2019 and December 31, 2018 primarily included stocks, bond funds and investment funds. Short-term Investments ProAssurance's short-term investments, which have a maturity at purchase of one year or less, are primarily comprised of investments in U.S. treasury obligations, commercial paper and money market funds. Short-term investments are carried at fair value which approximates the cost of the securities due to their short-term nature. BOLI ProAssurance holds BOLI policies that are carried at the current cash surrender value of the policies (original cost $33 million ). All insured individuals were members of ProAssurance management at the time the policies were acquired. The primary purpose of the program is to offset future employee benefit expenses through earnings on the cash value of the policies. ProAssurance is the owner and beneficiary of these policies. Net Investment Income Net investment income by investment category was as follows: Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Fixed maturities $ 18,275 $ 17,506 $ 35,792 $ 34,586 Equities 4,990 4,998 9,813 9,865 Short-term investments, including Other 1,619 1,332 3,454 2,639 BOLI 459 455 912 904 Investment fees and expenses (1,804 ) (1,907 ) (3,614 ) (3,583 ) Net investment income $ 23,539 $ 22,384 $ 46,357 $ 44,411 Investment in Unconsolidated Subsidiaries ProAssurance's investment in unconsolidated subsidiaries were as follows: June 30, 2019 Carrying Value (In thousands) Percentage June 30, December 31, Qualified affordable housing project tax credit partnerships See below $ 56,067 $ 65,677 Other tax credit partnerships See below 3,266 3,757 All other investments, primarily investment fund LPs/LLCs See below 326,298 298,323 $ 385,631 $ 367,757 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. ProAssurance's ownership percentage relative to two of the tax credit partnership interests is almost 100% ; these interests had a carrying value of $21.1 million at June 30, 2019 and $25.0 million at December 31, 2018 . ProAssurance's ownership percentage relative to the remaining tax credit partnership interests is less than 20% ; these interests had a carrying value of $35.0 million at June 30, 2019 and $40.7 million at December 31, 2018 . 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 12 . Other tax credit partnerships are comprised entirely of investments in historic tax credit partnerships. The historic tax credit partnerships generate investment returns by providing benefits to fund investors in the form of tax credits, tax deductible project operating losses and positive cash flows. The carrying value of these investments reflects ProAssurance's total funded commitments less any amortization. ProAssurance's ownership percentage relative to the historic tax credit partnerships is almost 100% . 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 12 . ProAssurance holds interests in investment fund LP s/ LLC s and other equity method investments and LP s/ LLC s which are not considered to be investment funds. ProAssurance's ownership percentage relative to two of the LP s/ LLC s is greater than 25%, which is expected to be reduced as the funds mature and other investors participate in the funds; these investments had a carrying value of $37.5 million at June 30, 2019 and $25.9 million at December 31, 2018 . ProAssurance's ownership percentage relative to the remaining investments and LP s/ LLC s is less than 25%; these interests had a carrying value of $288.8 million at June 30, 2019 and $272.4 million at December 31, 2018 . 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 historic tax credit partnerships. Losses recorded reflect ProAssurance's allocable portion of partnership operating losses. Tax credits reduce income tax expense in the period they are recognized. Losses recorded and tax credits recognized related to ProAssurance's tax credit partnership investments were as follows: Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Qualified affordable housing project tax credit partnerships Losses recorded $ 5,167 $ 5,612 $ 9,597 $ 9,712 Tax credits recognized $ 4,531 $ 4,624 $ 9,063 $ 9,237 Historic tax credit partnerships Losses recorded $ 302 $ 1,506 $ 491 $ 3,382 Tax credits recognized $ 103 $ 693 $ 206 $ 1,355 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 realized investment gains (losses): Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Total OTTI losses: Corporate debt $ — $ (404 ) $ (136 ) $ (404 ) Portion of OTTI losses recognized in other comprehensive income before taxes: Corporate debt — — 87 — Net impairment losses recognized in earnings — (404 ) (49 ) (404 ) Gross realized gains, available-for-sale fixed maturities 1,006 438 1,374 4,902 Gross realized (losses), available-for-sale fixed maturities (33 ) (1,725 ) (369 ) (3,772 ) Net realized gains (losses), trading fixed maturities 2 (73 ) (25 ) (73 ) Net realized gains (losses), equity investments 9,218 3,488 11,008 12,706 Net realized gains (losses), other investments 198 402 577 1,090 Change in unrealized holding gains (losses), trading fixed maturities 265 (170 ) 475 (219 ) Change in unrealized holding gains (losses), equity investments (2,459 ) 745 29,932 (23,099 ) Change in unrealized holding gains (losses), convertible securities, carried at fair value 1,110 90 3,006 (864 ) Other 1 4 2 11 Net realized investment gains (losses) $ 9,308 $ 2,795 $ 45,931 $ (9,722 ) ProAssurance did not recognize any OTTI for the three months ended June 30, 2019 . For the 2019 six-month period , ProAssurance recognized a nominal amount of both credit related OTTI in earnings and non-credit OTTI in OCI , both of which related to a corporate bond. ProAssurance recognized OTTI in earnings of $0.4 million during the 2018 three- and six- month periods related to debt instruments from one issuer in the energy sector. The following table presents a roll forward of cumulative credit losses recorded in earnings related to impaired debt securities for which a portion of the OTTI was recorded in OCI . Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Balance beginning of period $ 142 $ 1,313 $ 93 $ 1,313 Additional credit losses recognized during the period, related to securities for which: No OTTI has been previously recognized — — 49 — Balance June 30 $ 142 $ 1,313 $ 142 $ 1,313

Retroactive Insurance Contracts

Retroactive Insurance Contracts	6 Months Ended
	Jun. 30, 2019
Insurance [Abstract]
Retroactive Insurance Contracts	Retroactive Insurance Contracts ProAssurance offers custom alternative risk solutions including loss portfolio transfers for large healthcare entities who, most commonly, are exiting a line of business, changing an insurance approach or simply preferring to transfer risk. A loss portfolio transfer is a form of retroactive insurance coverage as the Company is assuming and accepting an entity’s existing open and future claim liabilities through the transfer of the entity’s loss reserves. In the second quarter of 2018, ProAssurance entered into a loss portfolio transfer with a large healthcare organization to cover a specific inventory of existing claims as well as provide tail coverage. As the contract included both prospective (tail) coverage and retroactive coverage, ProAssurance bifurcated the provisions of the contract and accounted for each component separately. As of the contract effective date, ProAssurance recognized total net premiums written and earned of $26.6 million , comprised of $7.9 million of prospective coverage and $18.7 million of retroactive coverage, and total net losses and loss adjustment expenses of $25.4 million in the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2018 . In addition, ProAssurance recorded a deferred gain of $0.6 million in the reserve for losses and loss adjustment expenses on the Condensed Consolidated Balance Sheet in the second quarter of 2018 representing the excess of premiums received over losses assumed related to the retroactive coverage which are amortized into earnings over the estimated claim payment period. Amortization of this deferred gain was insignificant for the three and six months ended June 30, 2019 and 2018 . For additional information regarding ProAssurance's accounting policy for retroactive insurance contracts, see Note 1 of the Notes to Consolidated Financial Statements included in ProAssurance's December 31, 2018 report on Form 10-K.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes ProAssurance estimates its annual effective tax rate at the end of each quarterly reporting period and uses this estimated rate as well as the tax effect of discrete items to record the provision for income taxes in the interim financial statements. The provision for income taxes is different from that which would be obtained by applying the statutory federal income tax rate to income before income taxes primarily because ProAssurance utilizes tax credit benefits transferred from tax credit partnership investments and because a portion of ProAssurance’s investment income is tax-exempt. ProAssurance had a receivable for federal and U.K. income taxes carried as a part of other assets of $4.1 million at June 30, 2019 and $3.5 million at December 31, 2018 . The liability for unrecognized tax benefits, which is included in the total receivable for federal and U.K. income taxes, was $4.5 million and $4.2 million at June 30, 2019 and December 31, 2018 , respectively, which included an accrued liability for interest of approximately $0.8 million and $0.6 million , respectively. Tax Cuts and Jobs Act ProAssurance recognized a nominal amount of tax expense related to the GILTI provision of the TCJA during the three and six months ended June 30, 2019 . ProAssurance has not recognized any incremental tax expense related to the BEAT provision of the TCJA during the three and six months ended June 30, 2019 . For additional information regarding ProAssurance's accounting for certain provisions of the TCJA, see Note 6 of the Notes to Consolidated Financial Statements in ProAssurance's December 31, 2018

Reserve for Losses and Loss Adj

Reserve for Losses and Loss Adjustment Expenses	6 Months Ended
	Jun. 30, 2019
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. ProAssurance believes that the methods it uses to establish reserves are reasonable and appropriate. Each year, ProAssurance uses internal actuaries to review the reserve for losses of each insurance subsidiary. ProAssurance also engages consulting actuaries to review ProAssurance claims data and provide observations regarding cost trends, rate adequacy and ultimate loss costs. ProAssurance considers the views of the actuaries as well as other factors, such as known, anticipated or estimated changes in frequency and severity of claims, loss retention levels and premium rates, in establishing the amount of its reserve for losses. The statutory filings of each insurance company with the insurance regulators must be accompanied by a consulting actuary's certification as to their respective reserves. ProAssurance partitions its reserve by accident year, which is the year in which the claim becomes its liability. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. ProAssurance also partitions its reserve by reserve type: case reserves and IBNR reserves. Case reserves are established by the claims department based upon the particular circumstances of each reported claim and represent ProAssurance’s estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; a reported loss for an individual claim equates to the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves represent an estimate, in the aggregate, of future development on losses that have been reported to ProAssurance plus an estimate of losses that have been incurred but not reported. Development of Prior Accident Years In addition to setting the initial reserve for the current accident year, each period ProAssurance reassesses the amount of reserve required for prior accident years. The foundation of ProAssurance’s reserve re-estimation process is an actuarial analysis that is performed by both the internal and consulting actuaries. This detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. In all, there are over 200 different partitions of ProAssurance's business for purposes of this analysis. ProAssurance believes that the use of consulting actuaries provides an independent view of the loss data as well as a broader perspective on industry loss trends. Activity in the reserve for losses and loss adjustment expenses is summarized as follows: (In thousands) Six Months Ended June 30, 2019 Six Months Ended June 30, 2018 Year Ended December 31, 2018 Balance, beginning of year $ 2,119,847 $ 2,048,381 $ 2,048,381 Less reinsurance recoverables on unpaid losses and loss adjustment expenses 343,820 335,585 335,585 Net balance, beginning of year 1,776,027 1,712,796 1,712,796 Net losses: Current year* 354,466 337,116 685,326 Favorable development of reserves established in prior years, net (26,271 ) (45,601 ) (92,116 ) Total 328,195 291,515 593,210 Paid related to: Current year (39,396 ) (34,174 ) (117,268 ) Prior years (221,378 ) (215,488 ) (412,711 ) Total paid (260,774 ) (249,662 ) (529,979 ) Net balance, end of period 1,843,448 1,754,649 1,776,027 Plus reinsurance recoverables on unpaid losses and loss adjustment expenses 352,012 324,168 343,820 Balance, end of period $ 2,195,460 $ 2,078,817 $ 2,119,847 * Current year net losses for the six months ended June 30, 2018 and year ended December 31, 2018 included incurred losses of $25.4 million related to a loss portfolio transfer entered into during 2018. For additional information regarding the loss portfolio transfer see Note 4. The favorable loss development recognized in the six months ended June 30, 2019 primarily reflected a lower than anticipated claims severity trend (i.e., the average size of a claim) for accident years 2012 through 2015 . The favorable loss development recognized in the six months ended June 30, 2018 primarily reflected a lower than anticipated claims severity trend for accident years 2011 through 2015 . The favorable loss development recognized in the twelve months ended December 31, 2018 primarily reflected a lower than anticipated claims severity trend for accident years 2011 through 2014. 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, 2018 report on Form 10-K.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2019
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, 2018 Form 10-K. As a member of Lloyd's , ProAssurance is required to provide capital to support its Lloyd's Syndicates through 2019 of up to $200 million , referred to as FAL . The Board, through a non-binding resolution, extended this commitment through 2022. At June 30, 2019 , ProAssurance's FAL was comprised of investment securities on deposit with Lloyd's with a carrying value of $134.8 million (see Note 3 ). ProAssurance has issued an unconditional revolving credit agreement to the Premium Trust Fund of Syndicate 1729 for the purpose of providing working capital with permitted borrowings of £30.0 million . In January 2019, the Syndicate Credit Agreement was amended to extend the current maturity to December 31, 2020 and to implement an annual auto-renewal feature which allows 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. Under the Syndicate Credit Agreement , advances bear interest at 3.8% annually and may be repaid at any time but are repayable upon demand after December 31, 2020 , subject to extension through the auto-renewal feature. During the second quarter of 2019, Syndicate 1729 repaid £24.2 million (approximately $30.7 million ) of the balance outstanding and as of June 30, 2019 , the unused commitment under this agreement approximated £28.4 million (approximately $36.1 million ). On occasion, 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, 2019 , ProAssurance had total funding commitments of approximately $263.9 million which primarily represented funding commitments related to non-public investment entities as well as the short-term loan commitment 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. In October 2018, ProAssurance entered into an agreement with a company to provide data analytics services for certain product lines within the Company's HCPL book of business. The agreement contains a minimum two year commitment with optional extension features for an annual fee of approximately $4.8 million per year with additional variable quarterly incentive fees based on service utilization metrics prescribed in the contract. ProAssurance incurred operating expense associated with this agreement of $1.3 million and $2.3 million during the 2019 three- and six- month periods , respectively, and as of June 30, 2019 , the remaining commitment under this agreement was approximately $6.3 million .

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Leases	Leases ProAssurance is involved in a number of operating leases primarily for office facilities. Office facility leases have remaining lease terms ranging from one year to thirteen years ; some of which include options to extend the leases for up to ten years , and some of which include an option to terminate the lease within one year. ProAssurance subleases certain office facilities to third parties and classifies these leases as operating leases. The following table provides a summary of the components of lease expense as well as the reporting location in the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2019 and 2018 . (In thousands) Location in the Condensed Consolidated Statements of Income and Comprehensive Income Three Months Ended June 30 Six Months Ended June 30 2019 2018 2019 2018 Operating lease expense (1) Operating expense $ 1,141 $ 1,261 $ 1,915 $ 2,528 Sublease income (2) Other income (38 ) (34 ) (76 ) (72 ) Net lease expense $ 1,103 $ 1,227 $ 1,839 $ 2,456 (1) Includes short-term lease costs and variable lease costs. For the three and six months ended June 30, 2019, no short-term lease costs were recognized and variable lease costs were nominal in amount. For the three and six months ended June 30, 2018, short-term lease costs and variable lease costs were each nominal in amount. (2) Sublease income excludes rental income from owned properties of $0.6 million and $1.2 million during the three and six months ended June 30, 2019, respectively, and $0.5 million and $1.1 million during the same respective periods of 2018, which is included in other income. See “Item 2. Properties” in ProAssurance's December 31, 2018 report on Form 10-K for a listing of currently owned properties. The following table provides supplemental lease information for operating leases on the Condensed Consolidated Balance Sheet as of June 30, 2019 . ($ in thousands) June 30, 2019 Operating lease ROU assets $ 20,374 Operating lease liabilities $ 21,131 Weighted-average remaining lease term 8.89 years Weighted-average discount rate 3.21 % The following table provides supplemental lease information for the Condensed Consolidated Statements of Cash Flows for the six months ended June 30, 2019 and 2018. Six Months Ended June 30 (In thousands) 2019 2018 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 757 $ 178 The following table is a schedule of remaining future minimum lease payments for operating leases that had an initial or remaining non-cancellable lease term in excess of one year as of June 30, 2019 . Operating lease payments exclude $1.9 million of future minimum lease payments for a lease signed but not yet commenced as of June 30, 2019 . This lease will commence in the third quarter of 2019 with a lease term of approximately eleven years . (In thousands) 2019 $ 2,178 2020 3,883 2021 3,530 2022 2,648 2023 1,955 Thereafter 10,142 Total future minimum lease payments $ 24,336 Less: Imputed interest 3,205 Total operating lease liabilities $ 21,131

Debt

Debt	6 Months Ended
	Jun. 30, 2019
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 Revolving Credit Agreement, outstanding borrowings are not permitted to exceed $250 million aggregately; Revolving Credit Agreement expires in 2020. The interest rate on borrowings is set at the time the borrowing is initiated or renewed. — — Mortgage Loans, outstanding borrowings are secured by first priority liens on two office buildings, and bear an interest rate of three-month LIBOR plus 1.325% (3.77% and 4.10%, respectively) determined on a quarterly basis. 38,340 39,064 Total principal 288,340 289,064 Less debt issuance costs 1,123 1,307 Debt less debt issuance costs $ 287,217 $ 287,757 Covenant Compliance There are no financial covenants associated with the Senior Notes due 2023. The Revolving Credit Agreement contains customary representations, covenants and events constituting default, and remedies for default. The Revolving Credit Agreement also defines financial covenants regarding permitted leverage ratios. ProAssurance is currently in compliance with all covenants of the Revolving Credit Agreement . The Mortgage Loans contain customary representations, covenants and events constituting default, and remedies for default. The Mortgage Loans also define a financial covenant regarding a permitted leverage ratio for each of the two ProAssurance subsidiaries that entered into the Mortgage Loans. ProAssurance's subsidiaries are currently in compliance with the financial covenant of the Mortgage Loans. Additional Information For additional information regarding ProAssurance's debt, see Note 10 of the Notes to Consolidated Financial Statements included in ProAssurance's December 31, 2018 report on Form 10-K.

Derivatives

Derivatives	6 Months Ended
	Jun. 30, 2019
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. As of June 30, 2019 , ProAssurance has not designated any derivative instruments as hedging instruments and does not use derivative instruments for trading purposes. ProAssurance utilizes an interest rate cap agreement with the objective of reducing the Company's exposure to interest rate risk related to its variable-rate Mortgage Loans. Additional information regarding the Company's Mortgage Loans is provided in Note 9 . Under the terms of the interest rate cap agreement, ProAssurance paid a premium of $2 million for the right to receive cash payments based upon a notional amount of $35 million if and when the three-month LIBOR rises above 2.35% . The Company's variable-rate Mortgage Loans bear an interest rate of three-month LIBOR plus 1.325% . Therefore, this derivative instrument is effectively ensuring the interest rate related to the Mortgage Loans is capped at a maximum of 3.675% until expiration of the interest rate cap agreement in October 2027 . During each of the three and six months ended June 30, 2019 , ProAssurance received a nominal cash payment associated with this agreement as a result of the three-month LIBOR rising above 2.35% , which was recorded as a reduction to interest expense. ProAssurance has designated the interest rate cap as an economic hedge (non-hedging instrument) of interest rate exposure and any change in fair value of the derivative is immediately recognized in earnings during the period of change. The following table provides a summary of the volume and fair value position of the interest rate cap as well as the reporting location in the Condensed Consolidated Balance Sheets as of June 30, 2019 and December 31, 2018 . ($ in thousands) June 30, 2019 December 31, 2018 Derivatives Not Designated as Hedging Instruments Location in the Condensed Consolidated Balance Sheets Number of Instruments Notional Amount (1) Estimated Fair Value (2) Number of Instruments Notional Amount (1) Estimated Fair Value (2) Interest Rate Cap Other assets 1 $ 35,000 $ 1,085 1 $ 35,000 $ 1,884 (1) Volume is represented by the derivative instrument's notional amount. (2) Additional information regarding the fair value of the Company's interest rate cap is provided in Note 2. The following table presents the pre-tax impact of the change in the fair value of the interest rate cap and the reporting location in the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2019 and 2018 . Gains (Losses) Recognized in Income on Derivatives (In thousands) Three Months Ended June 30 Six Months Ended June 30 Derivatives Not Designated as Hedging Instruments Location in the Condensed Consolidated Statements of Income and Comprehensive Income 2019 2018 2019 2018 Interest Rate Cap Interest expense $ (362 ) $ 282 $ (799 ) $ 857 As a result of this derivative instrument, ProAssurance is exposed to risk that the counterparty will fail to meet its contractual obligations. To mitigate this counterparty credit risk, ProAssurance only enters into derivative contracts with carefully selected major financial institutions based upon their credit ratings and monitors their creditworthiness. As of June 30, 2019 , the counterparty had an investment grade rating of BBB- and has performed in accordance with their contractual obligations.

Shareholders' Equity

Shareholders' Equity	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Shareholders' Equity	Shareholders’ Equity At June 30, 2019 and December 31, 2018 , 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. To date, the Board has not approved the issuance of preferred stock. ProAssurance declared cash dividends of $0.31 per share during each of the first two quarters of both 2019 and 2018 , totaling $33.3 million and $34.2 million , for each respective six-month period . At June 30, 2019 , Board authorizations for the repurchase of common shares or the retirement of outstanding debt of $110 million remained available for use. ProAssurance did no t repurchase any common shares during the six months ended June 30, 2019 and 2018 . Share-based compensation expense and related tax benefits were as follows: Three Months Ended June 30 Six Months Ended June 30 (In thousands) 2019 2018 2019 2018 Share-based compensation expense $ 1,092 $ 1,615 $ 2,320 $ 2,517 Related tax benefits $ 229 $ 339 $ 487 $ 529 ProAssurance awarded approximately 109,000 restricted share units and 25,000 base performance share units to employees in February 2019 . The fair value of each unit awarded was estimated at $40.18 , equal to the market value of a ProAssurance common share on the date of grant less the estimated present value of dividends during the vesting period. The majority of awards are charged to expense as an increase to additional paid-in capital over the service period (generally the vesting period) associated with the award. However, a nominal amount of awards are recorded as a liability as they are structured to be settled in cash. Restricted share units and performance share units vest in their entirety at the end of a three -year period following the grant date based on a continuous service requirement and, for performance share units, achievement of a performance objective. Partial vesting is permitted for retirees. For equity classified awards, a ProAssurance common share is issued for each unit once vesting requirements are met, except that units sufficient to satisfy required tax withholdings are paid in cash. The number of common shares issued for performance share units varies from 50% to 200% of base awards depending upon the degree to which stated performance objectives are achieved. ProAssurance issued approximately 64,500 and 34,300 common shares to employees in February 2019 related to restricted share units and performance share units, respectively, granted in 2016. Performance share units for the 2016 award were issued at a level of 95% . Liability classified awards, which are nominal in amount, are settled in cash at the end of the vesting period. ProAssurance issued approximately 2,000 common shares to employees in February 2019 as bonus compensation, as approved by the Compensation Committee of the Board. The shares issued were valued at fair value (the market price of a ProAssurance common share on the date of award). Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) For the three and six months ended June 30, 2019 and 2018 , OCI was almost entirely comprised of unrealized gains and losses, including non-credit impairment losses, arising during the period related to fixed maturity available-for-sale securities, less reclassification adjustments, as shown in the table that follows, net of tax. For the three and six months ended June 30, 2019 and 2018 , OCI included changes related to the reestimation of the defined benefit plan liability assumed in the Eastern acquisition which were nominal in amount. The defined benefit plan is frozen as to the earnings of additional benefits and the benefit plan liability is reestimated annually. At June 30, 2019 and December 31, 2018 , AOCI was almost entirely comprised of accumulated unrealized gains and losses from fixed maturity available-for-sale securities, including accumulated non-credit impairments recognized through OCI of $0.2 million and $0.1 million , respectively, net of tax. At June 30, 2019 and December 31, 2018 , accumulated changes in the defined benefit plan liability not yet recognized in earnings were nominal in amount. Due to the adoption of accounting guidance in the first quarter of 2018 related to certain impacts of the TCJA , ProAssurance increased AOCI by approximately $3.4 million with a corresponding decrease to retained earnings of the same amount as of the beginning of 2018. At June 30, 2019 and December 31, 2018 , tax effects were computed using the enacted federal corporate tax rate of 21% with the exception of unrealized gains and losses on available-for-sale securities held at the Company's U.K. and Cayman Islands entities which in both periods were immaterial in amount. Amounts reclassified from AOCI to net income and the amounts of deferred tax expense (benefit) included in OCI were as follows: Three Months Ended June 30 Six Months Ended June 30 (In thousands) 2019 2018 2019 2018 Reclassifications from AOCI to net income: Realized investment gains (losses) $ 974 $ (1,691 ) $ 957 $ 726 Tax effect, calculated using the 21% federal statutory tax rate (205 ) 355 (201 ) (153 ) Net reclassification adjustments $ 769 $ (1,336 ) $ 756 $ 573 Deferred tax expense (benefit) included in OCI $ 6,177 $ (2,185 ) $ 12,982 $ (9,245 )

Variable Interest Entities

Variable Interest Entities	6 Months Ended
	Jun. 30, 2019
Variable Interest Entities [Abstract]
Variable Interest Entities	Variable Interest Entities ProAssurance holds passive interests in a number of entities that are considered to be VIE s under GAAP guidance. ProAssurance's VIE interests principally consist of interests in LP s/ LLC s 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 $303.2 million at June 30, 2019 and $285.8 million at December 31, 2018 . ProAssurance does not have power over the activities that most significantly impact the economic performance of these VIE s and thus is not the primary beneficiary. Therefore, ProAssurance has not consolidated these VIE s. ProAssurance’s involvement with each VIE is limited to its direct ownership interest in the VIE . Except for the funding commitments disclosed in Note 7 , ProAssurance has no arrangements with any of the VIE s to provide other financial support to or on behalf of the VIE . At June 30, 2019 , ProAssurance’s maximum loss exposure relative to these investments was limited to the carrying value of ProAssurance’s investment in the VIE .

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Earnings Per Share	Earnings 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, performance share units and purchase match units have vested. The following table provides the weighted average number of common shares outstanding used in the calculation of the Company's basic and diluted earnings per share: (In thousands, except per share data) Three Months Ended June 30 Six Months Ended June 30 2019 2018 2019 2018 Weighted average number of common shares outstanding, basic 53,750 53,610 53,716 53,567 Dilutive effect of securities: Restricted Share Units 53 69 67 75 Performance Share Units 10 42 20 54 Purchase Match Units 15 20 15 20 Weighted average number of common shares outstanding, diluted 53,828 53,741 53,818 53,716 Effect of dilutive shares on earnings per share $ — $ — $ — $ — All dilutive common share equivalents are reflected in the earnings per share calculation while antidilutive common share equivalents are not reflected in the earnings per share calculation. There were no antidilutive common share equivalents for the three and six months ended June 30, 2019 . The diluted weighted average number of common shares outstanding for the three and six months ended June 30, 2018 excludes approximately 8,000 common share equivalents issuable under the Company's stock compensation plans, as their effect would be antidilutive.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2019
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. Segment Reorganization During the third quarter of 2018, ProAssurance altered its internal management reporting structure and the financial results evaluated by its CODM ; therefore, ProAssurance changed its operating segments to align with how the CODM currently oversees the business, allocates resources and evaluates operating performance. As a result of the segment reorganization, ProAssurance added an operating and reportable segment: Segregated Portfolio Cell Reinsurance. The Segregated Portfolio Cell Reinsurance segment provides the operating results of SPC s that predominately assume workers’ compensation insurance, healthcare professional liability insurance or a combination of the two. The underwriting results of the SPC s that assume workers’ compensation business and healthcare professional liability business were previously reported in the Company's Workers’ Compensation and Specialty P&C segments, respectively, and the results of investment assets solely allocated to SPC operations, previously reported in the Company's Corporate segment, are now reported in the Segregated Portfolio Cell Reinsurance segment. The Workers' Compensation segment has also been renamed "Workers' Compensation Insurance." All prior period segment information has been recast to conform to the current period presentation. The segment reorganization had no impact on previously reported consolidated financial results. Descriptions of ProAssurance's five operating and reportable segments are as follows: Specialty P&C is primarily focused on professional liability insurance and medical technology liability insurance. Professional liability insurance is primarily offered to healthcare providers and institutions and to attorneys and their firms. Medical technology liability insurance is offered to medical technology and life sciences companies that manufacture or distribute products including entities conducting human clinical trials. Prior to 2018, the Specialty P&C segment ceded certain premium to the Lloyd's Syndicates segment under a quota share agreement with Syndicate 1729 ; however, this agreement was not renewed on January 1, 2018. As discussed below, the Lloyd's Syndicates segment results are typically reported on a quarter delay. For consistency purposes, results from this ceding arrangement, other than cash receipts or disbursements, are reported within the Specialty P&C segment on the same one-quarter delay. Additionally, the Specialty P&C segment cedes healthcare professional liability business to certain SPCs in the Segregated Portfolio Cell Reinsurance segment. Workers' Compensation Insurance provides workers' compensation products primarily to employers with 1,000 or fewer employees. The segment's products include guaranteed cost, policyholder dividend policies, retrospectively-rated policies, deductible polices and alternative market solutions. Alternative market products include program design, fronting, claims administration, risk management, SPC rental, asset management and SPC management services. Alternative market premiums are 100% ceded to either SPCs in the Company's Segregated Portfolio Cell Reinsurance segment or, to a limited extent, to a captive insurer unaffiliated with ProAssurance. Segregated Portfolio Cell Reinsurance reflects the operating results (underwriting profit or loss, plus investment results) of SPC s at Inova Re and Eastern Re , the Company's Cayman Islands SPC operations. Each SPC is owned, fully or in part, by an agency, group or association, and the operating results of the SPC s are due to the participants of that cell. ProAssurance participates to a varying degree in the results of selected SPC s. SPC operating results due to external cell participants are reflected as an SPC dividend expense (income) in the Segregated Portfolio Cell Reinsurance segment and in ProAssurance's Condensed Consolidated Statements of Income and Comprehensive Income. In addition, the Segregated Portfolio Cell Reinsurance segment includes the SPC investment results as the investments are solely for the benefit of the cell participants, and investment results due to external cell participants are reflected in the SPC dividend expense (income). The majority of SPCs assume workers' compensation insurance, healthcare professional liability insurance or a combination of the two from the Workers' Compensation Insurance and Specialty P&C segments. In addition, one SPC at Eastern Re assumed an errors and omissions liability policy from a captive insurer unaffiliated with ProAssurance; the Company does not participate in the SPC that assumed this policy; therefore, the operating results of this policy are reflected in the SPC dividend expense (income). Lloyd's Syndicates includes operating results from ProAssurance's participation in Lloyd's of London Syndicate 1729 and Syndicate 6131 , which is an SPA that underwrites on a quota share basis with Syndicate 1729 . The results of this segment are normally reported on a quarter delay, except when information is available that is material to the current period. Furthermore, investment results associated with the majority of investment assets solely allocated to Lloyd's Syndicate operations and certain U.S. paid administrative expenses are reported concurrently as that information is available on an earlier time frame. For the 2019 underwriting year, ProAssurance slightly decreased its participation in the operating results of Syndicate 1729 from 62% to 61% ; however, due to the quarter delay these changes were not reflected in the Lloyd's Syndicates segment results until the second quarter of 2019. Furthermore, ProAssurance's 100% participation in Syndicate 6131 was not reflected in the Lloyd's Syndicates segment results until the second quarter of 2018 as Syndicate 6131 began writing business effective January 1, 2018. Syndicate 1729 underwrites risks over a wide range of property and casualty insurance and reinsurance lines in both the U.S. and international markets. Syndicate 6131 focuses on contingency and specialty property business, also within the U.S. and international markets. Corporate includes ProAssurance's investment operations, other than those reported in the Segregated Portfolio Cell Reinsurance and Lloyd's Syndicates segments, interest expense and U.S. income taxes. The segment also includes non-premium revenues generated outside of the Company's insurance entities and corporate expenses. The accounting policies of the segments are the same as those described in Note 1 of the Notes to Consolidated Financial Statements in ProAssurance’s December 31, 2018 report on Form 10-K and Note 1 herein. ProAssurance evaluates the performance of its Specialty P&C and Workers' Compensation Insurance segments based on before tax underwriting profit or loss, which excludes investment performance. ProAssurance evaluates the performance of its Segregated Portfolio Cell Reinsurance segment based on before tax operating profit or loss, which includes the investment performance of assets solely allocated to SPC operations. Performance of the Lloyd's Syndicates segment is evaluated based on underwriting profit or loss, plus 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. Financial results by segment were as follows: Three Months Ended June 30, 2019 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 126,011 $ 46,574 $ 19,284 $ 17,280 $ — $ — $ 209,149 Net investment income — — 368 1,199 21,972 — 23,539 Equity in earnings (loss) of unconsolidated subsidiaries — — — — (5,152 ) — (5,152 ) Net realized gains (losses) — — (94 ) 262 9,140 — 9,308 Other income (expense)* 1,470 725 135 32 833 (418 ) 2,777 Net losses and loss adjustment expenses (106,017 ) (30,625 ) (19,973 ) (11,825 ) — — (168,440 ) Underwriting, policy acquisition and operating expenses* (29,863 ) (14,368 ) (5,905 ) (7,564 ) (5,426 ) 418 (62,708 ) Segregated portfolio cells dividend (expense) income — — 7,033 — — — 7,033 Interest expense — — — — (4,247 ) — (4,247 ) Income tax benefit (expense) — — — 304 (27 ) — 277 Segment operating results $ (8,399 ) $ 2,306 $ 848 $ (312 ) $ 17,093 $ — $ 11,536 Significant non-cash items: Depreciation and amortization, net of accretion $ 1,623 $ 959 $ (32 ) $ (4 ) $ 2,071 $ — $ 4,617 Six Months Ended June 30, 2019 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 250,079 $ 92,512 $ 38,787 $ 35,920 $ — $ — $ 417,298 Net investment income — — 815 2,205 43,337 — 46,357 Equity in earnings (loss) of unconsolidated subsidiaries — — — — (5,962 ) — (5,962 ) Net realized gains (losses) — — 2,047 440 43,444 — 45,931 Other income (expense)* 2,680 1,454 221 (114 ) 1,738 (1,107 ) 4,872 Net losses and loss adjustment expenses (213,675 ) (61,068 ) (30,719 ) (22,733 ) — — (328,195 ) Underwriting, policy acquisition and operating expenses* (59,480 ) (28,559 ) (11,138 ) (16,033 ) (9,997 ) 1,107 (124,100 ) Segregated portfolio cells dividend (expense) income — — 2,246 — — — 2,246 Interest expense — — — — (8,576 ) — (8,576 ) Income tax benefit (expense) — — — — (6,685 ) — (6,685 ) Segment operating results $ (20,396 ) $ 4,339 $ 2,259 $ (315 ) $ 57,299 $ — $ 43,186 Significant non-cash items: Depreciation and amortization, net of accretion $ 3,359 $ 1,936 $ 14 $ (7 ) $ 4,351 $ — $ 9,653 Three Months Ended June 30, 2018 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 142,619 $ 45,234 $ 18,248 $ 17,490 $ — $ — $ 223,591 Net investment income — — 373 836 21,175 — 22,384 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 5,380 — 5,380 Net realized gains (losses) — — (457 ) (252 ) 3,504 — 2,795 Other income (expense)* 1,262 602 60 (436 ) 1,095 (539 ) 2,044 Net losses and loss adjustment expenses (110,856 ) (29,319 ) (9,048 ) (12,505 ) — — (161,728 ) Underwriting, policy acquisition and operating expenses* (27,922 ) (13,107 ) (5,440 ) (8,060 ) (5,621 ) 539 (59,611 ) Segregated portfolio cells dividend (expense) income — — (2,785 ) — — — (2,785 ) Interest expense — — — — (3,958 ) — (3,958 ) Income tax benefit (expense) — — — — 311 — 311 Segment operating results $ 5,103 $ 3,410 $ 951 $ (2,927 ) $ 21,886 $ — $ 28,423 Significant non-cash items: Depreciation and amortization, net of accretion $ 1,761 $ 958 $ 149 $ (2 ) $ 2,091 $ — $ 4,957 Six Months Ended June 30, 2018 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 257,567 $ 87,934 $ 35,284 $ 29,965 $ — $ — $ 410,750 Net investment income — — 729 1,587 42,095 — 44,411 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 7,019 — 7,019 Net realized gains (losses) — — (930 ) (306 ) (8,486 ) — (9,722 ) Other income (expense)* 2,519 1,453 90 (105 ) 2,037 (1,227 ) 4,767 Net losses and loss adjustment expenses (194,380 ) (57,143 ) (19,001 ) (20,991 ) — — (291,515 ) Underwriting, policy acquisition and operating expenses* (55,902 ) (26,137 ) (10,554 ) (15,306 ) (10,297 ) 1,227 (116,969 ) Segregated portfolio cells dividend (expense) income — — (4,532 ) — — — (4,532 ) Interest expense — — — — (7,663 ) — (7,663 ) Income tax benefit (expense) — — — (6 ) 3,739 — 3,733 Segment operating results $ 9,804 $ 6,107 $ 1,086 $ (5,162 ) $ 28,444 $ — $ 40,279 Significant non-cash items: Depreciation and amortization, net of accretion $ 3,628 $ 1,914 $ 310 $ (3 ) $ 5,187 $ — $ 11,036 * As a result of the third quarter 2018 segment reorganization, certain fees for services provided to the SPCs at Inova Re and Eastern Re are recorded as expenses within the Segregated Portfolio Cell Reinsurance segment and as other income within the Workers' Compensation Insurance segment. These fees are eliminated between segments in consolidation. These services primarily include SPC rental fees and were previously eliminated within the Company's Workers' Compensation segment. 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) 2019 2018 2019 2018 Specialty P&C Segment Gross premiums earned: Healthcare professional liability $ 128,893 $ 146,208 $ 256,914 $ 264,892 Legal professional liability 6,708 6,489 13,268 12,880 Medical technology liability 8,356 8,780 16,658 17,292 Other 1,212 119 1,346 230 Ceded premiums earned (19,158 ) (18,977 ) (38,107 ) (37,727 ) Segment net premiums earned 126,011 142,619 250,079 257,567 Workers' Compensation Insurance Segment Gross premiums earned: Traditional business 50,036 48,830 99,321 95,063 Alternative market business 20,846 20,648 41,837 40,029 Ceded premiums earned (24,308 ) (24,244 ) (48,646 ) (47,158 ) Segment net premiums earned 46,574 45,234 92,512 87,934 Segregated Portfolio Cell Reinsurance Segment Gross premiums earned: Workers' compensation (1) 20,229 19,197 40,726 37,036 Healthcare professional liability (2) 1,349 1,228 2,672 2,558 Other 120 — 240 — Ceded premiums earned (2,414 ) (2,177 ) (4,851 ) (4,310 ) Segment net premiums earned 19,284 18,248 38,787 35,284 Lloyd's Syndicates Segment Gross premiums earned: Property and casualty (3) 21,997 19,273 45,825 37,240 Ceded premiums earned (4,717 ) (1,783 ) (9,905 ) (7,275 ) Segment net premiums earned 17,280 17,490 35,920 29,965 Consolidated net premiums earned $ 209,149 $ 223,591 $ 417,298 $ 410,750 (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. (3) Includes premium assumed from the Specialty P&C segment of $0.1 million for the six months ended June 30, 2019 and $1.4 million and $3.3 million for three and six months ended June 30, 2018 , respectively.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2019
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 and its consolidated subsidiaries (ProAssurance, PRA or the Company). 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, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 . The accompanying Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and Notes contained in ProAssurance’s December 31, 2018 report on Form 10-K. In connection with its preparation of the Condensed Consolidated Financial Statements, ProAssurance evaluated events that occurred subsequent to June 30, 2019 for recognition or disclosure in its financial statements and notes to financial statements. Beginning in the third quarter of 2018, 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 14 .
Reclassifications	Reclassifications As a result of the third quarter of 2018 segment reorganization, prior period segment information in Note 14 has been recast to conform to the Company's current segment reporting (see Note 14 for further information).
Leases	Leases ProAssurance is involved in a number of leases, primarily for office facilities. The Company determines if an arrangement is a lease at the inception date of the contract and classifies all leases as either financing or operating. Operating leases are included in operating lease ROU assets and operating lease liabilities on the Condensed Consolidated Balance Sheet as of June 30, 2019 . The ROU asset represents the right to use the underlying asset for the lease term. As of June 30, 2019 , ProAssurance has no leases that are classified as financing leases. Operating ROU assets and operating lease liabilities are initially recognized as of the lease commencement date based on the present value of the remaining lease payments, discounted over the term of the lease using a discount rate determined based on information available as of the commencement date. As the majority of ProAssurance's lessors do not provide an implicit discount rate, the Company uses its collateralized incremental borrowing rate in determining the present value of remaining lease payments. Due to the adoption of ASU 2016-02 (see further discussion that follows), the Company used its collateralized incremental borrowing rate as of January 1, 2019 for operating leases that commenced prior to that date. Subsequent to the initial recognition, the operating ROU asset is amortized over the lease term on a straight-line basis as operating lease expense which 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, 2019 and 2018. Leases with an initial term of twelve months or less are considered short-term and are not recorded on the Condensed Consolidated Balance Sheet; lease expense for these leases is also recognized on a straight-line basis over the lease term. Additionally, for leases entered into or reassessed after the adoption of ASU 2016-02, ProAssurance accounts for lease and non-lease components of a contract as a single lease component. Operating lease ROU assets are evaluated for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The carrying amount of a ROU asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use of the underlying leased asset over the remaining lease term. That assessment is based on the carrying amount of the ROU asset at the date it is tested for recoverability and an impairment loss is measured and recognized as the amount by which the carrying amount of the ROU asset exceeds its fair value.
Accounting Changes Adopted and Not Yet Adopted	Accounting Changes Adopted Leases ( ASU 2016-02) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance that requires a lessee to recognize for all leases (with the exception of short-term leases) a lease liability, which is a lessee's obligation to make lease payments arising from a lease, measured on a discounted basis, and a right-of-use asset, which is an asset that represents the lessee's right to use, or control the use of, a specified asset for the lease term. ProAssurance adopted the guidance as of January 1, 2019 using a modified retrospective application and elected the transition option provided that allows companies to continue to apply legacy GAAP in comparative periods. Also, ProAssurance elected the package of practical expedients permitted under the guidance, which allowed the Company to carryforward its historical lease classification, its assessment on whether a contract is or contains a lease and its initial direct costs for any leases that existed prior to adoption of the new standard. Furthermore, ProAssurance elected to combine lease and non-lease components and to keep leases with an initial term of 12 months or less off the Condensed Consolidated Balance Sheet and recognize the associated lease payments in the Condensed Consolidated Statements of Income and Comprehensive Income on a straight-line basis over the lease term. ProAssurance recognized total ROU assets and total lease liabilities of approximately $19 million on the Condensed Consolidated Balance Sheet as of January 1, 2019 which relate to ProAssurance's real estate operating leases; the Company does not consider these leases to be material to its financial position. Adoption of this guidance had no material impact on ProAssurance's results of operation or cash flows. ProAssurance's Revolving Credit Agreement contains a financial covenant regarding permitted leverage ratios based upon Consolidated Funded Indebtedness to Consolidated Total Capitalization; however, adoption of this guidance had no material impact on this covenant. ProAssurance’s Mortgage Loans also contain a financial covenant regarding permitted leverage ratios, principally based upon SAP Consolidated Net Worth; however, as the NAIC did not adopt the principles found in ASU 2016-02, adoption of the guidance had no impact on this covenant. Premium Amortization on Purchased Callable Debt Securities ( ASU 2017-08) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance that will require the premium for certain callable debt securities to be amortized over a shorter period than is currently required. Currently amortization is permitted over the contractual life of the instrument and the guidance shortens the amortization to the earliest call date. The purpose of the guidance is to more closely align the amortization period of premiums to expectations incorporated in market pricing on the underlying securities. ProAssurance adopted the guidance as of January 1, 2019. As ProAssurance amortizes premium on callable debt securities to the earliest call date, adoption of the guidance had no material effect on ProAssurance’s results of operations, financial position or cash flows. Derivatives and Hedging ( ASU 2017-12) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance to improve financial reporting of hedging relationships to better portray the entity's risk management activities in the consolidated financial statements. The new guidance eliminates the requirement to separately measure and report hedge ineffectiveness and requires the entire change in the fair value of a hedging instrument to be presented in the same income statement line as the hedged item. ProAssurance adopted the guidance as of January 1, 2019. ProAssurance's derivative instrument at June 30, 2019 is not designated as a hedging instrument; therefore, adoption had no effect on ProAssurance's results of operations, financial position or cash flows. Improvements to Nonemployee Share-Based Payment Accounting ( ASU 2018-07) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued guidance which reduces the complexity in accounting for nonemployee share-based payment awards. The new guidance substantially aligns the accounting for nonemployee share-based payment awards with the accounting guidance for employee share-based payment awards with certain exceptions, including the inputs used in estimating the fair value of the nonemployee awards and the period of time and pattern of expense recognition. ProAssurance adopted the guidance as of January 1, 2019 using a modified retrospective application and recorded a cumulative-effect adjustment of approximately $0.4 million to beginning retained earnings in the Condensed Consolidated Statement of Changes in Capital for the six months ended June 30, 2019 . Adoption had no material effect of ProAssurance's results of operations or cash flows. Derivatives and Hedging - Inclusion of the Secured Overnight Financing Rate (SOFR) Overnight Index Swap as a Benchmark Interest Rate for Hedge Accounting Purposes (ASU 2018-16) Effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years, the FASB issued new guidance that permits the use of the Overnight Index Swap Rate based on the Secured Financing Rate as a U.S. benchmark interest rate for hedge accounting purposes. ProAssurance adopted the guidance as of January 1, 2019. As of June 30, 2019 , ProAssurance's derivative instrument is not designated as a hedging instrument; therefore, adoption had no effect on ProAssurance's results of operations, financial position or cash flows. Accounting Changes Not Yet Adopted Improvements to Financial Instruments - Credit Losses ( ASU 2016-13) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued guidance that replaces the incurred loss impairment methodology, which delays recognition of credit losses until a probable loss has been incurred, with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. Under the new guidance, credit losses are required to be recorded through an allowance for credit losses account and the income statement will reflect the initial recognition of lifetime expected credit losses for any newly recognized financial assets as well as increases or decreases of expected credit losses that have taken place during the period. Credit losses on available-for-sale fixed maturity securities will be required to be presented as an allowance, rather than as a write-down of the asset, limited to the amount by which the fair value is below amortized cost. Adoption of this guidance is not expected to have a material impact on ProAssurance's available-for-sale fixed maturity portfolio. In addition, ProAssurance's premiums receivable and receivables from reinsurers are also included in the scope of this new guidance; however, ProAssurance has not historically experienced material credit losses due to the financial condition of an insured or reinsurer. ProAssurance plans to adopt the guidance beginning January 1, 2020 and is in the process of evaluating the effect the new guidance would have on its results of operations and financial position. Simplifying the Test for Goodwill Impairment ( ASU 2017-04) Effective for the fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued guidance that simplifies the requirements to test goodwill for impairment for business entities that have goodwill reported in their financial statements. The guidance eliminates the second step of the impairment test which measures a goodwill impairment loss by comparing the implied fair value of a reporting unit's goodwill with the carrying amount. In addition, the guidance also eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment. ProAssurance plans to adopt the guidance beginning January 1, 2020. Adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Changes to the Disclosure Requirements for Fair Value Measurement ( ASU 2018-13) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued guidance that eliminates, modifies and adds certain disclosure requirements related to fair value measurements. The new guidance eliminates the requirements to disclose the transfers between Level 1 and Level 2 of the fair value hierarchy, the policy for the timing of transfers between levels of the fair value hierarchy and the valuation process for Level 3 fair value measurements while it modifies existing disclosure requirements related to measurement uncertainty and the requirement to disclose the timing of liquidation of an investee's assets for investments in certain entities that calculate NAV . The new guidance also adds requirements to disclose changes in unrealized gains and losses included in OCI for recurring Level 3 fair value measurements as well as the range and weighted average used to develop significant unobservable inputs for Level 3 fair value measurements. An entity is permitted to early adopt any eliminated or modified disclosure requirements and delay adoption of the additional disclosure requirements until the guidance is effective. During the third quarter of 2018, ProAssurance elected to early adopt the provisions that eliminate and modify certain disclosure requirements within Note 2 on a retrospective basis and adoption of these certain provisions had no material effect on ProAssurance’s results of operations, financial position or cash flows as it affected disclosures only. ProAssurance plans to adopt the additional disclosure requirements beginning January 1, 2020 and adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Intangibles - Goodwill and Other-Internal-Use Software ( ASU 2018-15) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB amended the new standard regarding accounting for implementation costs in cloud computing arrangements. The amended guidance substantially aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. ProAssurance plans to adopt the guidance beginning January 1, 2020. Adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Targeted Improvements to Related Party Guidance for VIEs ( ASU 2018-17) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB amended guidance which improves the consistency of the application of the VIE guidance for common control arrangements. The amended guidance requires an entity to consider indirect interests held through related parties under common control on a proportional basis rather than as the equivalent of a direct interest in its entirety when determining whether a decision-making fee is a variable interest. ProAssurance plans to adopt the guidance beginning January 1, 2020. As of June 30, 2019 ProAssurance does not have any material indirect interests held through related parties under common control; therefore, adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows. Collaborative Arrangements ( ASU 2018-18) Effective for fiscal years beginning after December 15, 2019 and interim periods within those fiscal years, the FASB issued new guidance which clarifies how to assess whether certain transactions between participants in a collaborative arrangement should be accounted for under the revenue from contracts with customers accounting standard when the counterpart is a customer. In addition, the guidance precludes an entity from presenting consideration from a transaction in a collaborative arrangement as revenue from contracts with customers if the counterparty is not a customer for that transaction. ProAssurance plans to adopt the guidance beginning January 1, 2020 and adoption is not expected to have a material effect on ProAssurance’s results of operations, financial position or cash flows.
Fair Value Measurement	The fair values for securities included in the Level 2 category, with the few exceptions described below, were developed by one of several third party, nationally recognized pricing services, including services that price only certain types of securities. Each service uses complex methodologies to determine values for securities and subject the values they develop to quality control reviews. Management selected a primary source for each type of security in the portfolio and reviewed the values provided for reasonableness by comparing data to alternate pricing services and to available market and trade data. Values that appeared inconsistent were further reviewed for appropriateness. Any value that did not appear reasonable was discussed with the service that provided the value and adjusted, if necessary. There were no material changes to the values supplied by the pricing services during the three and six months ended June 30, 2019 . Level 2 Valuations Below is a summary description of the valuation methodologies primarily used by the pricing services for securities in the Level 2 category, by security type: U.S. Treasury obligations were valued based on quoted prices for identical assets, or, in markets that are not active, quotes for similar assets, taking into consideration adjustments for variations in contractual cash flows and yields to maturity. U.S. Government-sponsored enterprise obligations were valued using pricing models that consider current and historical market data, normal trading conventions, credit ratings, and the particular structure and characteristics of the security being valued, such as yield to maturity, redemption options, and contractual cash flows. Adjustments to model inputs or model results were included in the valuation process when necessary to reflect recent regulatory, government or corporate actions or significant economic, industry or geographic events affecting the security’s fair value. State and municipal bonds were valued using a series of matrices that considered credit ratings, the structure of the security, the sector in which the security falls, yields, and contractual cash flows. Valuations were further adjusted, when necessary, to reflect the expected effect on fair value of recent significant economic or geographic events or ratings changes. Corporate debt, multiple observable inputs consisted primarily of corporate bonds, but also included a small number of bank loans. The methodology used to value Level 2 corporate bonds was the same as the methodology previously described for U.S. Government-sponsored enterprise obligations. Bank loans were valued based on an average of broker quotes for the loans in question, if available. If quotes were not available, the loans were valued based on quoted prices for comparable loans or, if the loan was newly issued, by comparison to similar seasoned issues. Broker quotes were compared to actual trade prices to permit assessment of the reliability of the quotes; unreliable quotes were not considered in quoted averages. Residential and commercial mortgage-backed securities were valued using a pricing matrix which considers the issuer type, coupon rate and longest cash flows outstanding. The matrix used was based on the most recently available market information. Agency and non-agency collateralized mortgage obligations were both valued using models that consider the structure of the security, current and historical information regarding prepayment speeds, ratings and ratings updates, and current and historical interest rate and interest rate spread data. Other asset-backed securities were valued using models that consider the structure of the security, monthly payment information, current and historical information regarding prepayment speeds, ratings and ratings updates, and current and historical interest rate and interest rate spread data. Spreads and prepayment speeds consider collateral type. Fixed maturities, trading , are held by the Lloyd's Syndicates segment and include U.S. Treasury obligations, U.S. Government-sponsored enterprise obligations, corporate debt with multiple observable inputs and other asset-backed securities. These securities were valued using the respective valuation methodologies discussed above for each security type. Short-term investments were securities maturing within one year, carried at fair value which approximated the cost of the securities due to their short-term nature. Other investments consisted primarily of convertible bonds valued using a pricing model that incorporated selected dealer quotes as well as current market data regarding equity prices and risk free rates. If dealer quotes were unavailable for the security being valued, quotes for securities with similar terms and credit status were used in the pricing model. Dealer quotes selected for use were those considered most accurate based on parameters such as underwriter status and historical reliability. Other assets consisted of an interest rate cap derivative instrument, which is discussed in Note 10 , valued using a model which considers the volatilities from other instruments with similar maturities, strike prices, durations and forward yield curves. Level 3 Valuations Below is a summary description of the valuation methodologies used as well as quantitative information regarding securities in the Level 3 category, by security type: Level 3 Valuation Methodologies Corporate debt, limited observable inputs consisted of corporate bonds valued using dealer quotes for similar securities or discounted cash flow models using yields currently available for similar securities. Similar securities are defined as securities of comparable credit quality that have like terms and payment features. Assessments of credit quality were based on NRSRO ratings, if available, or were subjectively determined by management if not available. At June 30, 2019 , 100% of the securities were rated and the average rating was AA- . At December 31, 2018 , 54% of the securities were rated and the average rating was BBB+ . Other commercial mortgage-backed and other asset-backed securities consisted of securitizations of receivables valued using dealer quotes for similar securities or discounted cash flow models using yields currently available for similar securities. Similar securities are defined as securities of comparable credit quality that have like terms and payment features. Assessments of credit quality were based on NRSRO ratings, if available, or were subjectively determined by management if not available. At June 30, 2019 , 28% of the securities were rated and the average rating was A- . At December 31, 2018 , 25% of the securities were rated and the average rating was AAA . Other investments consisted of convertible securities for which limited observable inputs were available at June 30, 2019 and December 31, 2018 . The securities were valued internally based on expected cash flows, including the expected final recovery, discounted at a yield that considered the lack of liquidity and the financial status of the issuer.

Basis of Presentation (Tables)

Basis of Presentation (Tables)	6 Months Ended
	Jun. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of other liabilities	Other liabilities consisted of the following: (In thousands) June 30, 2019 December 31, 2018 SPC dividends payable $ 51,952 $ 53,604 Unpaid shareholder dividends 16,656 43,446 All other 135,332 102,245 Total other liabilities $ 203,940 $ 199,295

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	6 Months Ended
	Jun. 30, 2019
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, 2019 and December 31, 2018 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. June 30, 2019 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 $ — $ 110,449 $ — $ 110,449 U.S. Government-sponsored enterprise obligations — 29,147 — 29,147 State and municipal bonds — 290,243 — 290,243 Corporate debt, multiple observable inputs — 1,304,560 — 1,304,560 Corporate debt, limited observable inputs — — 2,304 2,304 Residential mortgage-backed securities — 182,258 — 182,258 Agency commercial mortgage-backed securities — 11,475 — 11,475 Other commercial mortgage-backed securities — 62,769 1,171 63,940 Other asset-backed securities — 231,978 2,992 234,970 Fixed maturities, trading — 43,156 — 43,156 Equity investments Financial 58,517 — — 58,517 Utilities/Energy 42,788 — — 42,788 Consumer oriented 40,588 — — 40,588 Industrial 39,186 — — 39,186 Bond funds 174,795 — — 174,795 All other 43,268 — — 43,268 Short-term investments 243,908 43,101 — 287,009 Other investments — 33,200 624 33,824 Other assets — 1,085 — 1,085 Total assets categorized within the fair value hierarchy $ 643,050 $ 2,343,421 $ 7,091 2,993,562 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Equity investments 21,283 Investment in unconsolidated subsidiaries 291,000 Total assets at fair value $ 3,305,845 December 31, 2018 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 $ — $ 120,201 $ — $ 120,201 U.S. Government-sponsored enterprise obligations — 35,354 — 35,354 State and municipal bonds — 293,772 — 293,772 Corporate debt, multiple observable inputs 2,319 1,216,834 — 1,219,153 Corporate debt, limited observable inputs — — 4,322 4,322 Residential mortgage-backed securities — 181,238 — 181,238 Agency commercial mortgage-backed securities — 13,108 — 13,108 Other commercial mortgage-backed securities — 30,993 — 30,993 Other asset-backed securities — 191,807 3,850 195,657 Fixed maturities, trading — 38,188 — 38,188 Equity investments Financial 62,344 — — 62,344 Utilities/Energy 46,533 — — 46,533 Consumer oriented 47,462 — — 47,462 Industrial 41,487 — — 41,487 Bond funds 174,753 — — 174,753 All other 50,066 — — 50,066 Short-term investments 265,910 42,409 — 308,319 Other investments — 31,341 3 31,344 Other assets — 1,884 — 1,884 Total assets categorized within the fair value hierarchy $ 690,874 $ 2,197,129 $ 8,175 2,896,178 Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy, reported as a part of: Equity investments 20,292 Investment in unconsolidated subsidiaries 268,436 Total assets at fair value $ 3,184,906
Schedule of quantitative information regarding level 3 valuations	Quantitative Information Regarding Level 3 Valuations Fair Value at ($ in thousands) June 30, 2019 December 31, 2018 Valuation Technique Unobservable Input Range Assets: Corporate debt, limited observable inputs $2,304 $4,322 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other commercial mortgage-backed securities $1,171 — Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other asset-backed securities $2,992 $3,850 Market Comparable Comparability Adjustment 0% - 5% (2.5%) Discounted Cash Flows Comparability Adjustment 0% - 5% (2.5%) Other investments $624 $3 Discounted Cash Flows Comparability Adjustment 0% - 10% (5%)
Schedule of fair value measurements - level 3 assets	The following tables (the Level 3 Tables) present summary information regarding changes in the fair value of assets measured at fair value using Level 3 inputs. June 30, 2019 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance March 31, 2019 $ 4,296 $ 4,132 $ 3 $ 8,431 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income — (22 ) — (22 ) Net realized investment gains (losses) — — 33 33 Included in other comprehensive income 8 53 — 61 Purchases — — 170 170 Sales (2,000 ) — — (2,000 ) Transfers in — — 418 418 Transfers out — — — — Balance June 30, 2019 $ 2,304 $ 4,163 $ 624 $ 7,091 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — June 30, 2019 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance December 31, 2018 $ 4,322 $ 3,850 $ 3 $ 8,175 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income 2 (140 ) — (138 ) Net realized investment gains (losses) — — 33 33 Included in other comprehensive income 11 210 — 221 Purchases 1,305 — 170 1,475 Sales (2,136 ) (6 ) — (2,142 ) Transfers in — 1,200 418 1,618 Transfers out (1,200 ) (951 ) — (2,151 ) Balance June 30, 2019 $ 2,304 $ 4,163 $ 624 $ 7,091 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — June 30, 2018 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance March 31, 2018 $ 15,097 $ 17,323 $ 365 $ 32,785 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (36 ) 1 — (35 ) Net realized investment gains (losses) (8 ) — 6 (2 ) Included in other comprehensive income (90 ) (111 ) — (201 ) Purchases — 3,225 — 3,225 Sales (1,644 ) (158 ) (366 ) (2,168 ) Transfers in 558 — — 558 Transfers out (5,497 ) (10,860 ) — (16,357 ) Balance June 30, 2018 $ 8,380 $ 9,420 $ 5 $ 17,805 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ — June 30, 2018 Level 3 Fair Value Measurements – Assets (In thousands) Corporate Debt Asset-backed Securities Other investments Total Balance December 31, 2017 $ 13,703 $ 4,986 $ 409 $ 19,098 Total gains (losses) realized and unrealized: Included in earnings, as a part of: Net investment income (74 ) 1 — (73 ) Net realized investment gains (losses) (8 ) — (38 ) (46 ) Included in other comprehensive income (128 ) (141 ) — (269 ) Purchases 6,005 16,678 — 22,683 Sales (4,549 ) (185 ) (366 ) (5,100 ) Transfers in 2,627 — — 2,627 Transfers out (9,196 ) (11,919 ) — (21,115 ) Balance June 30, 2018 $ 8,380 $ 9,420 $ 5 $ 17,805 Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end $ — $ — $ — $ —
Schedule of investments in LLCs and limited partnerships	The amount of ProAssurance's unfunded commitments related to these investments as of June 30, 2019 and fair values of these investments as of June 30, 2019 and December 31, 2018 was as follows: Unfunded Fair Value (In thousands) June 30, June 30, December 31, Equity investments: Mortgage fund (1) None $ 21,283 $ 20,292 Investment in unconsolidated subsidiaries: Private debt funds (2) $18,333 14,032 18,196 Long equity fund (3) None 6,511 6,561 Long/short equity funds (4) None 29,066 28,805 Non-public equity funds (5) $82,544 122,411 114,811 Multi-strategy fund of funds (6) None 9,596 9,322 Credit funds (7) $2,971 40,838 29,164 Long/short commodities fund (8) None 14,287 12,958 Strategy focused funds (9) $48,228 54,259 48,619 291,000 268,436 Total investments carried at NAV $ 312,283 $ 288,728 Below is additional information regarding each of the investments listed in the table above as of June 30, 2019 . (1) This investment fund is focused on the structured mortgage market. The fund will primarily invest in U.S. Agency mortgage-backed securities. Redemptions are allowed at the end of any calendar quarter with a prior notice requirement of 65 days and are paid within 45 days at the end of the redemption dealing day. (2) This investment is comprised of interests in three 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; the other two do not permit redemption. Income and capital are to be periodically distributed at the discretion of the LP s over an anticipated time frame that spans from three to eight years . (3) This fund is a LP that holds long equities of public international companies. Redemptions are allowed at the end of any calendar month with a prior notice requirement of 15 days and are paid within 10 days of the end of the calendar month of the redemption request. (4) This investment is comprised of interests in multiple unrelated LP funds. The funds hold primarily long and short North American equities and target absolute returns using strategies designed to take advantage of market opportunities. The funds generally permit quarterly or semi-annual capital redemptions subject to notice requirements of 30 to 90 days . For some funds, redemptions above specified thresholds (lowest threshold is 90% ) may be only partially payable until after a fund audit is completed and are then payable within 30 days . (5) 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 LP s. Two of the LP s 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 . (6) This fund is a LLC structured to build and manage low volatility, multi-manager portfolios that have little or no correlation to the broader fixed income and equity security markets. Redemptions are not permitted but offers to repurchase units of the LLC may be extended periodically. (7) This investment is comprised of four 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. A third fund focuses on private middle market company mezzanine loans, while the remaining fund seeks event driven opportunities across the corporate credit spectrum. Two funds are allowed redemptions at any quarter-end with a prior notice requirement of 90 days , one fund permits redemption at any quarter-end with a prior notice requirement of 180 days and one fund does not allow redemptions. (8) This fund is a LLC invested across a broad range of commodities and focuses primarily on market neutral, relative value strategies, seeking to generate absolute returns with low correlation to broad commodity, equity and fixed income markets. Following an initial one-year lock-up period, redemptions are allowed with a prior notice requirement of 30 days and are payable within 30 days . (9) This investment is comprised of multiple unrelated LP s/ LLC s funds. One fund is a 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. Another fund is a LP focused on North American energy infrastructure assets that allows redemption with consent of the General Partner. The remaining funds are real estate focused LP s, 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. All fair values provided primarily fall within the Level 3 fair value category. June 30, 2019 December 31, 2018 (In thousands) Carrying Fair Carrying Fair Financial assets: BOLI $ 65,008 $ 65,008 $ 64,096 $ 64,096 Other investments $ 2,901 $ 2,902 $ 2,943 $ 2,943 Other assets $ 27,324 $ 27,323 $ 35,921 $ 35,468 Financial liabilities: Senior notes due 2023* $ 250,000 $ 272,115 $ 250,000 $ 264,810 Mortgage Loans* $ 38,340 $ 38,340 $ 39,064 $ 39,064 Other liabilities $ 41,095 $ 41,095 $ 21,300 $ 21,300 * Carrying value excludes debt issuance costs.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule of available-for-sale fixed maturities	Available-for-sale fixed maturities at June 30, 2019 and December 31, 2018 included the following: June 30, 2019 (In thousands) Amortized Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available for sale U.S. Treasury obligations $ 108,961 $ 1,655 $ 167 $ 110,449 U.S. Government-sponsored enterprise obligations 29,035 141 29 29,147 State and municipal bonds 279,664 10,591 12 290,243 Corporate debt 1,283,074 26,112 2,322 1,306,864 Residential mortgage-backed securities 181,183 2,140 1,065 182,258 Agency commercial mortgage-backed securities 11,271 224 20 11,475 Other commercial mortgage-backed securities 62,593 1,381 34 63,940 Other asset-backed securities 232,766 2,292 88 234,970 $ 2,188,547 $ 44,536 $ 3,737 $ 2,229,346 December 31, 2018 (In thousands) Amortized Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Fixed maturities, available for sale U.S. Treasury obligations $ 121,274 $ 331 $ 1,404 $ 120,201 U.S. Government-sponsored enterprise obligations 35,758 25 429 35,354 State and municipal bonds 289,544 4,877 649 293,772 Corporate debt 1,244,577 3,328 24,430 1,223,475 Residential mortgage-backed securities 184,463 814 4,039 181,238 Agency commercial mortgage-backed securities 13,296 12 200 13,108 Other commercial mortgage-backed securities 31,330 38 375 30,993 Other asset-backed securities 196,583 254 1,180 195,657 $ 2,116,825 $ 9,679 $ 32,706 $ 2,093,798
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, 2019 , 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 $ 108,961 $ 16,545 $ 71,405 $ 22,076 $ 423 $ 110,449 U.S. Government-sponsored enterprise obligations 29,035 5,391 6,005 17,608 143 29,147 State and municipal bonds 279,664 14,647 116,908 133,199 25,489 290,243 Corporate debt 1,283,074 154,196 782,386 343,561 26,721 1,306,864 Residential mortgage-backed securities 181,183 182,258 Agency commercial mortgage-backed securities 11,271 11,475 Other commercial mortgage-backed securities 62,593 63,940 Other asset-backed securities 232,766 234,970 $ 2,188,547 $ 2,229,346
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, 2019 and December 31, 2018 , including the length of time the investment had been held in a continuous unrealized loss position. June 30, 2019 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 $ 34,577 $ 167 $ 2,006 $ 12 $ 32,571 $ 155 U.S. Government-sponsored enterprise obligations 9,372 29 1,986 14 7,386 15 State and municipal bonds 4,589 12 2,663 7 1,926 5 Corporate debt 242,882 2,322 46,959 514 195,923 1,808 Residential mortgage-backed securities 81,377 1,065 1,166 1 80,211 1,064 Agency commercial mortgage-backed securities 317 20 — — 317 20 Other commercial mortgage-backed securities 4,163 34 — — 4,163 34 Other asset-backed securities 42,436 88 4,660 1 37,776 87 $ 419,713 $ 3,737 $ 59,440 $ 549 $ 360,273 $ 3,188 December 31, 2018 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 $ 97,969 $ 1,405 $ 20,221 $ 119 $ 77,748 $ 1,286 U.S. Government-sponsored enterprise obligations 33,677 429 20,479 126 13,198 303 State and municipal bonds 63,094 648 30,924 143 32,170 505 Corporate debt 938,651 24,429 447,891 8,804 490,760 15,625 Residential mortgage-backed securities 157,120 4,039 27,311 209 129,809 3,830 Agency commercial mortgage-backed securities 9,822 200 4,566 22 5,256 178 Other commercial mortgage-backed securities 22,924 375 13,348 164 9,576 211 Other asset-backed securities 142,470 1,181 70,218 236 72,252 945 $ 1,465,727 $ 32,706 $ 634,958 $ 9,823 $ 830,769 $ 22,883
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) 2019 2018 2019 2018 Proceeds from sales (exclusive of maturities and paydowns) $ 61.8 $ 115.8 $ 93.3 $ 495.0 Purchases $ 171.8 $ 184.6 $ 350.9 $ 552.5
Schedule of net investment income	Net investment income by investment category was as follows: Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Fixed maturities $ 18,275 $ 17,506 $ 35,792 $ 34,586 Equities 4,990 4,998 9,813 9,865 Short-term investments, including Other 1,619 1,332 3,454 2,639 BOLI 459 455 912 904 Investment fees and expenses (1,804 ) (1,907 ) (3,614 ) (3,583 ) Net investment income $ 23,539 $ 22,384 $ 46,357 $ 44,411
Schedule of investment in unconsolidated subsidiaries	ProAssurance's investment in unconsolidated subsidiaries were as follows: June 30, 2019 Carrying Value (In thousands) Percentage June 30, December 31, Qualified affordable housing project tax credit partnerships See below $ 56,067 $ 65,677 Other tax credit partnerships See below 3,266 3,757 All other investments, primarily investment fund LPs/LLCs See below 326,298 298,323 $ 385,631 $ 367,757
Schedule of losses and tax credits related to tax credit partnership investments	Losses recorded and tax credits recognized related to ProAssurance's tax credit partnership investments were as follows: Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Qualified affordable housing project tax credit partnerships Losses recorded $ 5,167 $ 5,612 $ 9,597 $ 9,712 Tax credits recognized $ 4,531 $ 4,624 $ 9,063 $ 9,237 Historic tax credit partnerships Losses recorded $ 302 $ 1,506 $ 491 $ 3,382 Tax credits recognized $ 103 $ 693 $ 206 $ 1,355
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 realized investment gains (losses): Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Total OTTI losses: Corporate debt $ — $ (404 ) $ (136 ) $ (404 ) Portion of OTTI losses recognized in other comprehensive income before taxes: Corporate debt — — 87 — Net impairment losses recognized in earnings — (404 ) (49 ) (404 ) Gross realized gains, available-for-sale fixed maturities 1,006 438 1,374 4,902 Gross realized (losses), available-for-sale fixed maturities (33 ) (1,725 ) (369 ) (3,772 ) Net realized gains (losses), trading fixed maturities 2 (73 ) (25 ) (73 ) Net realized gains (losses), equity investments 9,218 3,488 11,008 12,706 Net realized gains (losses), other investments 198 402 577 1,090 Change in unrealized holding gains (losses), trading fixed maturities 265 (170 ) 475 (219 ) Change in unrealized holding gains (losses), equity investments (2,459 ) 745 29,932 (23,099 ) Change in unrealized holding gains (losses), convertible securities, carried at fair value 1,110 90 3,006 (864 ) Other 1 4 2 11 Net realized investment gains (losses) $ 9,308 $ 2,795 $ 45,931 $ (9,722 )
Schedule of OTTI recorded in OCI	The following table presents a roll forward of cumulative credit losses recorded in earnings related to impaired debt securities for which a portion of the OTTI was recorded in OCI . Three Months Ended Six Months Ended (In thousands) 2019 2018 2019 2018 Balance beginning of period $ 142 $ 1,313 $ 93 $ 1,313 Additional credit losses recognized during the period, related to securities for which: No OTTI has been previously recognized — — 49 — Balance June 30 $ 142 $ 1,313 $ 142 $ 1,313

Reserve for Losses and Loss A_2

Reserve for Losses and Loss Adjustment Expenses (Tables)	6 Months Ended
	Jun. 30, 2019
Insurance [Abstract]
Summary 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, 2019 Six Months Ended June 30, 2018 Year Ended December 31, 2018 Balance, beginning of year $ 2,119,847 $ 2,048,381 $ 2,048,381 Less reinsurance recoverables on unpaid losses and loss adjustment expenses 343,820 335,585 335,585 Net balance, beginning of year 1,776,027 1,712,796 1,712,796 Net losses: Current year* 354,466 337,116 685,326 Favorable development of reserves established in prior years, net (26,271 ) (45,601 ) (92,116 ) Total 328,195 291,515 593,210 Paid related to: Current year (39,396 ) (34,174 ) (117,268 ) Prior years (221,378 ) (215,488 ) (412,711 ) Total paid (260,774 ) (249,662 ) (529,979 ) Net balance, end of period 1,843,448 1,754,649 1,776,027 Plus reinsurance recoverables on unpaid losses and loss adjustment expenses 352,012 324,168 343,820 Balance, end of period $ 2,195,460 $ 2,078,817 $ 2,119,847 * Current year net losses for the six months ended June 30, 2018 and year ended December 31, 2018 included incurred losses of $25.4 million related to a loss portfolio transfer entered into during 2018. For additional information regarding the loss portfolio transfer see Note 4.

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases [Abstract]
Schedule of Lease Cost	The following table provides a summary of the components of lease expense as well as the reporting location in the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2019 and 2018 . (In thousands) Location in the Condensed Consolidated Statements of Income and Comprehensive Income Three Months Ended June 30 Six Months Ended June 30 2019 2018 2019 2018 Operating lease expense (1) Operating expense $ 1,141 $ 1,261 $ 1,915 $ 2,528 Sublease income (2) Other income (38 ) (34 ) (76 ) (72 ) Net lease expense $ 1,103 $ 1,227 $ 1,839 $ 2,456 (1) Includes short-term lease costs and variable lease costs. For the three and six months ended June 30, 2019, no short-term lease costs were recognized and variable lease costs were nominal in amount. For the three and six months ended June 30, 2018, short-term lease costs and variable lease costs were each nominal in amount. (2) Sublease income excludes rental income from owned properties of $0.6 million and $1.2 million during the three and six months ended June 30, 2019, respectively, and $0.5 million and $1.1 million during the same respective periods of 2018, which is included in other income. See “Item 2. Properties” in ProAssurance's December 31, 2018 report on Form 10-K for a listing of currently owned properties. The following table provides supplemental lease information for operating leases on the Condensed Consolidated Balance Sheet as of June 30, 2019 . ($ in thousands) June 30, 2019 Operating lease ROU assets $ 20,374 Operating lease liabilities $ 21,131 Weighted-average remaining lease term 8.89 years Weighted-average discount rate 3.21 % The following table provides supplemental lease information for the Condensed Consolidated Statements of Cash Flows for the six months ended June 30, 2019 and 2018. Six Months Ended June 30 (In thousands) 2019 2018 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 757 $ 178
Schedule of Lease Liability	The following table is a schedule of remaining future minimum lease payments for operating leases that had an initial or remaining non-cancellable lease term in excess of one year as of June 30, 2019 . Operating lease payments exclude $1.9 million of future minimum lease payments for a lease signed but not yet commenced as of June 30, 2019 . This lease will commence in the third quarter of 2019 with a lease term of approximately eleven years . (In thousands) 2019 $ 2,178 2020 3,883 2021 3,530 2022 2,648 2023 1,955 Thereafter 10,142 Total future minimum lease payments $ 24,336 Less: Imputed interest 3,205 Total operating lease liabilities $ 21,131

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 30, 2019
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 Revolving Credit Agreement, outstanding borrowings are not permitted to exceed $250 million aggregately; Revolving Credit Agreement expires in 2020. The interest rate on borrowings is set at the time the borrowing is initiated or renewed. — — Mortgage Loans, outstanding borrowings are secured by first priority liens on two office buildings, and bear an interest rate of three-month LIBOR plus 1.325% (3.77% and 4.10%, respectively) determined on a quarterly basis. 38,340 39,064 Total principal 288,340 289,064 Less debt issuance costs 1,123 1,307 Debt less debt issuance costs $ 287,217 $ 287,757

Derivatives (Tables)

Derivatives (Tables)	6 Months Ended
	Jun. 30, 2019
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 cap as well as the reporting location in the Condensed Consolidated Balance Sheets as of June 30, 2019 and December 31, 2018 . ($ in thousands) June 30, 2019 December 31, 2018 Derivatives Not Designated as Hedging Instruments Location in the Condensed Consolidated Balance Sheets Number of Instruments Notional Amount (1) Estimated Fair Value (2) Number of Instruments Notional Amount (1) Estimated Fair Value (2) Interest Rate Cap Other assets 1 $ 35,000 $ 1,085 1 $ 35,000 $ 1,884 (1) Volume is represented by the derivative instrument's notional amount. (2) Additional information regarding the fair value of the Company's interest rate cap is provided in Note 2. The following table presents the pre-tax impact of the change in the fair value of the interest rate cap and the reporting location in the Condensed Consolidated Statements of Income and Comprehensive Income for the three and six months ended June 30, 2019 and 2018 . Gains (Losses) Recognized in Income on Derivatives (In thousands) Three Months Ended June 30 Six Months Ended June 30 Derivatives Not Designated as Hedging Instruments Location in the Condensed Consolidated Statements of Income and Comprehensive Income 2019 2018 2019 2018 Interest Rate Cap Interest expense $ (362 ) $ 282 $ (799 ) $ 857

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2019
Equity [Abstract]
Schedule of share-based compensation expense and related tax benefits	Share-based compensation expense and related tax benefits were as follows: Three Months Ended June 30 Six Months Ended June 30 (In thousands) 2019 2018 2019 2018 Share-based compensation expense $ 1,092 $ 1,615 $ 2,320 $ 2,517 Related tax benefits $ 229 $ 339 $ 487 $ 529
Schedule of reclassification adjustments related to available-for-sale securities	Amounts reclassified from AOCI to net income and the amounts of deferred tax expense (benefit) included in OCI were as follows: Three Months Ended June 30 Six Months Ended June 30 (In thousands) 2019 2018 2019 2018 Reclassifications from AOCI to net income: Realized investment gains (losses) $ 974 $ (1,691 ) $ 957 $ 726 Tax effect, calculated using the 21% federal statutory tax rate (205 ) 355 (201 ) (153 ) Net reclassification adjustments $ 769 $ (1,336 ) $ 756 $ 573 Deferred tax expense (benefit) included in OCI $ 6,177 $ (2,185 ) $ 12,982 $ (9,245 )

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Schedule of earnings per share, basic and diluted	The following table provides the weighted average number of common shares outstanding used in the calculation of the Company's basic and diluted earnings per share: (In thousands, except per share data) Three Months Ended June 30 Six Months Ended June 30 2019 2018 2019 2018 Weighted average number of common shares outstanding, basic 53,750 53,610 53,716 53,567 Dilutive effect of securities: Restricted Share Units 53 69 67 75 Performance Share Units 10 42 20 54 Purchase Match Units 15 20 15 20 Weighted average number of common shares outstanding, diluted 53,828 53,741 53,818 53,716 Effect of dilutive shares on earnings per share $ — $ — $ — $ —

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Schedule of segment reporting information, by segment	Financial results by segment were as follows: Three Months Ended June 30, 2019 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 126,011 $ 46,574 $ 19,284 $ 17,280 $ — $ — $ 209,149 Net investment income — — 368 1,199 21,972 — 23,539 Equity in earnings (loss) of unconsolidated subsidiaries — — — — (5,152 ) — (5,152 ) Net realized gains (losses) — — (94 ) 262 9,140 — 9,308 Other income (expense)* 1,470 725 135 32 833 (418 ) 2,777 Net losses and loss adjustment expenses (106,017 ) (30,625 ) (19,973 ) (11,825 ) — — (168,440 ) Underwriting, policy acquisition and operating expenses* (29,863 ) (14,368 ) (5,905 ) (7,564 ) (5,426 ) 418 (62,708 ) Segregated portfolio cells dividend (expense) income — — 7,033 — — — 7,033 Interest expense — — — — (4,247 ) — (4,247 ) Income tax benefit (expense) — — — 304 (27 ) — 277 Segment operating results $ (8,399 ) $ 2,306 $ 848 $ (312 ) $ 17,093 $ — $ 11,536 Significant non-cash items: Depreciation and amortization, net of accretion $ 1,623 $ 959 $ (32 ) $ (4 ) $ 2,071 $ — $ 4,617 Six Months Ended June 30, 2019 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 250,079 $ 92,512 $ 38,787 $ 35,920 $ — $ — $ 417,298 Net investment income — — 815 2,205 43,337 — 46,357 Equity in earnings (loss) of unconsolidated subsidiaries — — — — (5,962 ) — (5,962 ) Net realized gains (losses) — — 2,047 440 43,444 — 45,931 Other income (expense)* 2,680 1,454 221 (114 ) 1,738 (1,107 ) 4,872 Net losses and loss adjustment expenses (213,675 ) (61,068 ) (30,719 ) (22,733 ) — — (328,195 ) Underwriting, policy acquisition and operating expenses* (59,480 ) (28,559 ) (11,138 ) (16,033 ) (9,997 ) 1,107 (124,100 ) Segregated portfolio cells dividend (expense) income — — 2,246 — — — 2,246 Interest expense — — — — (8,576 ) — (8,576 ) Income tax benefit (expense) — — — — (6,685 ) — (6,685 ) Segment operating results $ (20,396 ) $ 4,339 $ 2,259 $ (315 ) $ 57,299 $ — $ 43,186 Significant non-cash items: Depreciation and amortization, net of accretion $ 3,359 $ 1,936 $ 14 $ (7 ) $ 4,351 $ — $ 9,653 Three Months Ended June 30, 2018 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 142,619 $ 45,234 $ 18,248 $ 17,490 $ — $ — $ 223,591 Net investment income — — 373 836 21,175 — 22,384 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 5,380 — 5,380 Net realized gains (losses) — — (457 ) (252 ) 3,504 — 2,795 Other income (expense)* 1,262 602 60 (436 ) 1,095 (539 ) 2,044 Net losses and loss adjustment expenses (110,856 ) (29,319 ) (9,048 ) (12,505 ) — — (161,728 ) Underwriting, policy acquisition and operating expenses* (27,922 ) (13,107 ) (5,440 ) (8,060 ) (5,621 ) 539 (59,611 ) Segregated portfolio cells dividend (expense) income — — (2,785 ) — — — (2,785 ) Interest expense — — — — (3,958 ) — (3,958 ) Income tax benefit (expense) — — — — 311 — 311 Segment operating results $ 5,103 $ 3,410 $ 951 $ (2,927 ) $ 21,886 $ — $ 28,423 Significant non-cash items: Depreciation and amortization, net of accretion $ 1,761 $ 958 $ 149 $ (2 ) $ 2,091 $ — $ 4,957 Six Months Ended June 30, 2018 (In thousands) Specialty P&C Workers' Compensation Insurance Segregated Portfolio Cell Reinsurance Lloyd's Syndicates Corporate Inter-segment Eliminations Consolidated Net premiums earned $ 257,567 $ 87,934 $ 35,284 $ 29,965 $ — $ — $ 410,750 Net investment income — — 729 1,587 42,095 — 44,411 Equity in earnings (loss) of unconsolidated subsidiaries — — — — 7,019 — 7,019 Net realized gains (losses) — — (930 ) (306 ) (8,486 ) — (9,722 ) Other income (expense)* 2,519 1,453 90 (105 ) 2,037 (1,227 ) 4,767 Net losses and loss adjustment expenses (194,380 ) (57,143 ) (19,001 ) (20,991 ) — — (291,515 ) Underwriting, policy acquisition and operating expenses* (55,902 ) (26,137 ) (10,554 ) (15,306 ) (10,297 ) 1,227 (116,969 ) Segregated portfolio cells dividend (expense) income — — (4,532 ) — — — (4,532 ) Interest expense — — — — (7,663 ) — (7,663 ) Income tax benefit (expense) — — — (6 ) 3,739 — 3,733 Segment operating results $ 9,804 $ 6,107 $ 1,086 $ (5,162 ) $ 28,444 $ — $ 40,279 Significant non-cash items: Depreciation and amortization, net of accretion $ 3,628 $ 1,914 $ 310 $ (3 ) $ 5,187 $ — $ 11,036 * As a result of the third quarter 2018 segment reorganization, certain fees for services provided to the SPCs at Inova Re and Eastern Re are recorded as expenses within the Segregated Portfolio Cell Reinsurance segment and as other income within the Workers' Compensation Insurance segment. These fees are eliminated between segments in consolidation. These services primarily include SPC rental fees and were previously eliminated within the Company's Workers' Compensation segment.
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) 2019 2018 2019 2018 Specialty P&C Segment Gross premiums earned: Healthcare professional liability $ 128,893 $ 146,208 $ 256,914 $ 264,892 Legal professional liability 6,708 6,489 13,268 12,880 Medical technology liability 8,356 8,780 16,658 17,292 Other 1,212 119 1,346 230 Ceded premiums earned (19,158 ) (18,977 ) (38,107 ) (37,727 ) Segment net premiums earned 126,011 142,619 250,079 257,567 Workers' Compensation Insurance Segment Gross premiums earned: Traditional business 50,036 48,830 99,321 95,063 Alternative market business 20,846 20,648 41,837 40,029 Ceded premiums earned (24,308 ) (24,244 ) (48,646 ) (47,158 ) Segment net premiums earned 46,574 45,234 92,512 87,934 Segregated Portfolio Cell Reinsurance Segment Gross premiums earned: Workers' compensation (1) 20,229 19,197 40,726 37,036 Healthcare professional liability (2) 1,349 1,228 2,672 2,558 Other 120 — 240 — Ceded premiums earned (2,414 ) (2,177 ) (4,851 ) (4,310 ) Segment net premiums earned 19,284 18,248 38,787 35,284 Lloyd's Syndicates Segment Gross premiums earned: Property and casualty (3) 21,997 19,273 45,825 37,240 Ceded premiums earned (4,717 ) (1,783 ) (9,905 ) (7,275 ) Segment net premiums earned 17,280 17,490 35,920 29,965 Consolidated net premiums earned $ 209,149 $ 223,591 $ 417,298 $ 410,750 (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. (3) Includes premium assumed from the Specialty P&C segment of $0.1 million for the six months ended June 30, 2019 and $1.4 million and $3.3 million for three and six months ended June 30, 2018 , respectively.

Basis of Presentation (Narrativ

Basis of Presentation (Narrative) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2019USD ($)segment	Jan. 01, 2019USD ($)	Dec. 31, 2018USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of reportable segments (in segments) | segment	5,000
Operating lease ROU assets	$ 20,374	$ 19,000
Operating lease liabilities	21,131	19,000
Retained earnings	$ 1,581,273		$ 1,571,847
Accounting Standards Update 2018-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings		$ 400

Basis of Presentation (Other Li

Basis of Presentation (Other Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
SPC dividends payable	$ 51,952	$ 53,604
Unpaid shareholder dividends	16,656	43,446	$ 17,630
All other	135,332	102,245
Total other liabilities	$ 203,940	$ 199,295

Fair Value Measurement (Narrati

Fair Value Measurement (Narrative) (Details)	6 Months Ended	12 Months Ended
	Jun. 30, 2019USD ($)Agreement	Dec. 31, 2018USD ($)
Credit Derivatives [Line Items]
Fair value of funded deferred compensation assets	$ 25,000,000	$ 24,100,000
Separate line of credit agreements (in agreements) | Agreement	2
Fair Value, Measurements, Nonrecurring
Credit Derivatives [Line Items]
Fair value, net asset (liability)	$ 0	$ 0
Corporate debt, limited observable inputs | NRSRO | NRSRO, Rating AA Minus
Credit Derivatives [Line Items]
Credit rating	100.00%
Corporate debt, limited observable inputs | NRSRO | NRSRO, Rating BBB Plus
Credit Derivatives [Line Items]
Credit rating		54.00%
Other asset-backed securities | NRSRO | NRSRO, Rating A Minus
Credit Derivatives [Line Items]
Credit rating	28.00%
Other asset-backed securities | NRSRO | NRSRO, Rating AAA
Credit Derivatives [Line Items]
Credit rating		25.00%

Fair Value Measurement (Assets

Fair Value Measurement (Assets Measured at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets:
AFS debt securities	$ 2,229,346	$ 2,093,798
Fixed maturities, trading	43,156	38,188
Equity investments	420,425	442,937
Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy	312,283	288,728
U.S. Treasury obligations
Assets:
AFS debt securities	110,449	120,201
U.S. Government-sponsored enterprise obligations
Assets:
AFS debt securities	29,147	35,354
State and municipal bonds
Assets:
AFS debt securities	290,243	293,772
Corporate debt, limited observable inputs | Level 3
Assets:
AFS debt securities	2,304	4,322
Residential mortgage-backed securities
Assets:
AFS debt securities	182,258	181,238
Agency commercial mortgage-backed securities
Assets:
AFS debt securities	11,475	13,108
Other commercial mortgage-backed securities
Assets:
AFS debt securities	63,940	30,993
Other commercial mortgage-backed securities | Level 3
Assets:
AFS debt securities	1,171	0
Other asset-backed securities
Assets:
AFS debt securities	234,970	195,657
Other investments | Level 3
Assets:
Total assets categorized within the fair value hierarchy	624	3
Equity investments
Assets:
Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy	291,000	268,436
Recurring
Assets:
Fixed maturities, trading	43,156	38,188
Other assets	1,085	1,884
Total assets categorized within the fair value hierarchy	2,993,562	2,896,178
Recurring | Level 1
Assets:
Fixed maturities, trading	0	0
Other assets	0	0
Total assets categorized within the fair value hierarchy	643,050	690,874
Recurring | Level 2
Assets:
Fixed maturities, trading	43,156	38,188
Other assets	1,085	1,884
Total assets categorized within the fair value hierarchy	2,343,421	2,197,129
Recurring | Level 3
Assets:
Fixed maturities, trading	0	0
Other assets	0	0
Total assets categorized within the fair value hierarchy	7,091	8,175
Recurring | Fair Value Measured at Net Asset Value Per Share
Assets:
Total assets at fair value	3,305,845	3,184,906
Recurring | U.S. Treasury obligations
Assets:
AFS debt securities	110,449	120,201
Recurring | U.S. Treasury obligations | Level 1
Assets:
AFS debt securities	0	0
Recurring | U.S. Treasury obligations | Level 2
Assets:
AFS debt securities	110,449	120,201
Recurring | U.S. Treasury obligations | Level 3
Assets:
AFS debt securities	0	0
Recurring | U.S. Government-sponsored enterprise obligations
Assets:
AFS debt securities	29,147	35,354
Recurring | U.S. Government-sponsored enterprise obligations | Level 1
Assets:
AFS debt securities	0	0
Recurring | U.S. Government-sponsored enterprise obligations | Level 2
Assets:
AFS debt securities	29,147	35,354
Recurring | U.S. Government-sponsored enterprise obligations | Level 3
Assets:
AFS debt securities	0	0
Recurring | State and municipal bonds
Assets:
AFS debt securities	290,243	293,772
Recurring | State and municipal bonds | Level 1
Assets:
AFS debt securities	0	0
Recurring | State and municipal bonds | Level 2
Assets:
AFS debt securities	290,243	293,772
Recurring | State and municipal bonds | Level 3
Assets:
AFS debt securities	0	0
Recurring | Corporate debt, multiple observable inputs
Assets:
AFS debt securities	1,304,560	1,219,153
Recurring | Corporate debt, multiple observable inputs | Level 1
Assets:
AFS debt securities	0	2,319
Recurring | Corporate debt, multiple observable inputs | Level 2
Assets:
AFS debt securities	1,304,560	1,216,834
Recurring | Corporate debt, multiple observable inputs | Level 3
Assets:
AFS debt securities	0	0
Recurring | Corporate debt, limited observable inputs
Assets:
AFS debt securities	2,304	4,322
Recurring | Corporate debt, limited observable inputs | Level 1
Assets:
AFS debt securities	0	0
Recurring | Corporate debt, limited observable inputs | Level 2
Assets:
AFS debt securities	0	0
Recurring | Corporate debt, limited observable inputs | Level 3
Assets:
AFS debt securities	2,304	4,322
Recurring | Residential mortgage-backed securities
Assets:
AFS debt securities	182,258	181,238
Recurring | Residential mortgage-backed securities | Level 1
Assets:
AFS debt securities	0	0
Recurring | Residential mortgage-backed securities | Level 2
Assets:
AFS debt securities	182,258	181,238
Recurring | Residential mortgage-backed securities | Level 3
Assets:
AFS debt securities	0	0
Recurring | Agency commercial mortgage-backed securities
Assets:
AFS debt securities	11,475	13,108
Recurring | Agency commercial mortgage-backed securities | Level 1
Assets:
AFS debt securities	0	0
Recurring | Agency commercial mortgage-backed securities | Level 2
Assets:
AFS debt securities	11,475	13,108
Recurring | Agency commercial mortgage-backed securities | Level 3
Assets:
AFS debt securities	0	0
Recurring | Other commercial mortgage-backed securities
Assets:
AFS debt securities	63,940	30,993
Recurring | Other commercial mortgage-backed securities | Level 1
Assets:
AFS debt securities	0	0
Recurring | Other commercial mortgage-backed securities | Level 2
Assets:
AFS debt securities	62,769	30,993
Recurring | Other commercial mortgage-backed securities | Level 3
Assets:
AFS debt securities	1,171	0
Recurring | Other asset-backed securities
Assets:
AFS debt securities	234,970	195,657
Recurring | Other asset-backed securities | Level 1
Assets:
AFS debt securities	0	0
Recurring | Other asset-backed securities | Level 2
Assets:
AFS debt securities	231,978	191,807
Recurring | Other asset-backed securities | Level 3
Assets:
AFS debt securities	2,992	3,850
Recurring | Financial
Assets:
Equity investments	58,517	62,344
Recurring | Financial | Level 1
Assets:
Equity investments	58,517	62,344
Recurring | Financial | Level 2
Assets:
Equity investments	0	0
Recurring | Financial | Level 3
Assets:
Equity investments	0	0
Recurring | Utilities/Energy
Assets:
Equity investments	42,788	46,533
Recurring | Utilities/Energy | Level 1
Assets:
Equity investments	42,788	46,533
Recurring | Utilities/Energy | Level 2
Assets:
Equity investments	0	0
Recurring | Utilities/Energy | Level 3
Assets:
Equity investments	0	0
Recurring | Consumer oriented
Assets:
Equity investments	40,588	47,462
Recurring | Consumer oriented | Level 1
Assets:
Equity investments	40,588	47,462
Recurring | Consumer oriented | Level 2
Assets:
Equity investments	0	0
Recurring | Consumer oriented | Level 3
Assets:
Equity investments	0	0
Recurring | Industrial
Assets:
Equity investments	39,186	41,487
Recurring | Industrial | Level 1
Assets:
Equity investments	39,186	41,487
Recurring | Industrial | Level 2
Assets:
Equity investments	0	0
Recurring | Industrial | Level 3
Assets:
Equity investments	0	0
Recurring | Bond funds
Assets:
Equity investments	174,795	174,753
Recurring | Bond funds | Level 1
Assets:
Equity investments	174,795	174,753
Recurring | Bond funds | Level 2
Assets:
Equity investments	0	0
Recurring | Bond funds | Level 3
Assets:
Equity investments	0	0
Recurring | All other
Assets:
Equity investments	43,268	50,066
Recurring | All other | Level 1
Assets:
Equity investments	43,268	50,066
Recurring | All other | Level 2
Assets:
Equity investments	0	0
Recurring | All other | Level 3
Assets:
Equity investments	0	0
Recurring | Short-term investments
Assets:
Short-term and other investments	287,009	308,319
Recurring | Short-term investments | Level 1
Assets:
Short-term and other investments	243,908	265,910
Recurring | Short-term investments | Level 2
Assets:
Short-term and other investments	43,101	42,409
Recurring | Short-term investments | Level 3
Assets:
Short-term and other investments	0	0
Recurring | Other investments
Assets:
Short-term and other investments	33,824	31,344
Recurring | Other investments | Level 1
Assets:
Short-term and other investments	0	0
Recurring | Other investments | Level 2
Assets:
Short-term and other investments	33,200	31,341
Recurring | Other investments | Level 3
Assets:
Short-term and other investments	624	3
Equities | Recurring | Equities | Fair Value Measured at Net Asset Value Per Share
Assets:
Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy	21,283	20,292
Equity investments | Recurring | Fair Value Measured at Net Asset Value Per Share
Assets:
Assets carried at NAV, which approximates fair value and which are not categorized within the fair value hierarchy	$ 291,000	$ 268,436

Fair Value Measurement (Quantit

Fair Value Measurement (Quantitative Information Regarding Level 3 Valuations) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets:
AFS debt securities	$ 2,229,346	$ 2,093,798
Corporate debt, limited observable inputs | Level 3
Assets:
AFS debt securities	$ 2,304	4,322
Corporate debt, limited observable inputs | Level 3 | Measurement input, comparability adjustment | Market Comparable Securities | Minimum
Assets:
Available-for-sale, measurement input	0
Corporate debt, limited observable inputs | Level 3 | Measurement input, comparability adjustment | Market Comparable Securities | Maximum
Assets:
Available-for-sale, measurement input	0.05
Corporate debt, limited observable inputs | Level 3 | Measurement input, comparability adjustment | Market Comparable Securities | Weighted average
Assets:
Available-for-sale, measurement input	0.025
Corporate debt, limited observable inputs | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Minimum
Assets:
Available-for-sale, measurement input	0
Corporate debt, limited observable inputs | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Maximum
Assets:
Available-for-sale, measurement input	0.05
Corporate debt, limited observable inputs | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Weighted average
Assets:
Available-for-sale, measurement input	0.025
Other commercial mortgage-backed securities
Assets:
AFS debt securities	$ 63,940	30,993
Other commercial mortgage-backed securities | Level 3
Assets:
AFS debt securities	1,171	0
Other asset-backed securities | Level 3
Assets:
AFS debt securities	$ 2,992	3,850
Other asset-backed securities | Level 3 | Measurement input, comparability adjustment | Market Comparable Securities | Minimum
Assets:
Available-for-sale, measurement input	0
Other asset-backed securities | Level 3 | Measurement input, comparability adjustment | Market Comparable Securities | Maximum
Assets:
Available-for-sale, measurement input	0.05
Other asset-backed securities | Level 3 | Measurement input, comparability adjustment | Market Comparable Securities | Weighted average
Assets:
Available-for-sale, measurement input	0.025
Other asset-backed securities | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Minimum
Assets:
Available-for-sale, measurement input	0
Other asset-backed securities | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Maximum
Assets:
Available-for-sale, measurement input	0.05
Other asset-backed securities | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Weighted average
Assets:
Available-for-sale, measurement input	0.025
Other investments | Level 3
Assets:
Assets measured at fair value	$ 624	$ 3
Other investments | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Minimum
Assets:
Other assets, measurement input	0.00%
Other investments | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Maximum
Assets:
Other assets, measurement input	10.00%
Other investments | Level 3 | Measurement input, comparability adjustment | Discounted Cash Flows | Weighted average
Assets:
Other assets, measurement input	5.00%

Fair Value Measurement (Level 3

Fair Value Measurement (Level 3 Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	$ 8,431	$ 32,785	$ 8,175	$ 19,098
Included in earnings, as a part of:
Included in other comprehensive income	61	(201)	221	(269)
Purchases	170	3,225	1,475	22,683
Sales	(2,000)	(2,168)	(2,142)	(5,100)
Transfers in	418	558	1,618	2,627
Transfers out	0	(16,357)	(2,151)	(21,115)
Ending balance	7,091	17,805	7,091	17,805
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0	0	0
Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	(22)	(35)	(138)	(73)
Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	33	(2)	33	(46)
Corporate Debt
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	4,296	15,097	4,322	13,703
Included in earnings, as a part of:
Included in other comprehensive income	8	(90)	11	(128)
Purchases	0	0	1,305	6,005
Sales	(2,000)	(1,644)	(2,136)	(4,549)
Transfers in	0	558	0	2,627
Transfers out		(5,497)	(1,200)	(9,196)
Ending balance	2,304	8,380	2,304	8,380
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0	0	0
Corporate Debt | Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	(36)	2	(74)
Corporate Debt | Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	(8)	0	(8)
Asset-backed Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	4,132	17,323	3,850	4,986
Included in earnings, as a part of:
Included in other comprehensive income	53	(111)	210	(141)
Purchases	0	3,225	0	16,678
Sales	0	(158)	(6)	(185)
Transfers in	0	0	1,200	0
Transfers out	0	(10,860)	(951)	(11,919)
Ending balance	4,163	9,420	4,163	9,420
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0	0	0
Asset-backed Securities | Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	(22)	1	(140)	1
Asset-backed Securities | Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	0	0	0
Other investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning balance	3	365	3	409
Included in earnings, as a part of:
Included in other comprehensive income	0	0	0	0
Purchases	170	0	170	0
Sales	0	(366)	0	(366)
Transfers in	418	0	418	0
Transfers out	0	0	0	0
Ending balance	624	5	624	5
Change in unrealized gains (losses) included in earnings for the above period for Level 3 assets held at period-end	0	0	0	0
Other investments | Net investment income
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	0	0	0	0
Other investments | Net realized investment gains (losses)
Included in earnings, as a part of:
Total gains (losses) realized and unrealized, included in earnings	$ 33	$ 6	$ 33	$ (38)

Fair Value Measurement (Investm

Fair Value Measurement (Investments in LLCs and Limited Partnerships) (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 312,283,000	$ 288,728,000
Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	291,000,000	268,436,000
Mortgage fund | Equities
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0
Fair Value	21,283,000	20,292,000
Private debt funds | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	18,333,000
Fair Value	14,032,000	18,196,000
Long equity fund | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0
Fair Value	6,511,000	6,561,000
Long/short equity funds | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0
Fair Value	29,066,000	28,805,000
Non-public equity funds | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	82,544,000
Fair Value	122,411,000	114,811,000
Multi-strategy fund of funds | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0
Fair Value	9,596,000	9,322,000
Credit fund | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	2,971,000
Fair Value	40,838,000	29,164,000
Long/short commodities fund | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0
Fair Value	14,287,000	12,958,000
Strategy focused fund | Equity investments
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	48,228,000
Fair Value	$ 54,259,000	$ 48,619,000

Fair Value Measurement (Inves_2

Fair Value Measurement (Investments in LLCs and Limited Partnerships Footnote) (Details)	6 Months Ended
	Jun. 30, 2019
Mortgage fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investment redemption notice period	65 days
Payment period for redemption of LP valued at NAV	45 days
Secured debt fund | Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	3 years
Secured debt fund | Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	8 years
Long equity fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investment redemption notice period	15 days
Payment period for redemption of LP valued at NAV	10 days
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
Redemption percentage of LP at NAV for which initial payment is limited	90.00%
Long/short equity funds | Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investment redemption notice period	30 days
Long/short equity funds | Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investment redemption notice period	90 days
Non-public equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	10 years
Credit fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investment redemption notice period, two funds	90 days
Investment redemption notice period, one fund	180 days
Long/short commodities fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Investment redemption notice period	30 days
Long/short commodities fund | Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Payment period for redemption of LP valued at NAV	30 days

Fair Value Measurement (Financi

Fair Value Measurement (Financial Instruments Not Measured at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Carrying Value
Financial assets:
Other assets	$ 27,324	$ 35,921
Financial liabilities:
Other liabilities	41,095	21,300
Carrying Value | Senior notes due 2023
Financial liabilities:
Debt instruments	250,000	250,000
Carrying Value | Mortgage loans
Financial liabilities:
Debt instruments	38,340	39,064
Carrying Value | BOLI
Financial assets:
Short-term and other investments	65,008	64,096
Carrying Value | Other investments
Financial assets:
Short-term and other investments	2,901	2,943
Fair Value
Financial assets:
Other assets	27,323	35,468
Financial liabilities:
Other liabilities	41,095	21,300
Fair Value | Senior notes due 2023
Financial liabilities:
Debt instruments	272,115	264,810
Fair Value | Mortgage loans
Financial liabilities:
Debt instruments	38,340	39,064
Fair Value | BOLI
Financial assets:
Short-term and other investments	65,008	64,096
Fair Value | Other investments
Financial assets:
Short-term and other investments	$ 2,902	$ 2,943

Investments (Narrative) (Detail

Investments (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)Businessinvestment_interestIssuerSecurity	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)Businessinvestment_interestIssuerSecurity	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)IssuerSecurity
Reclassifications from AOCI to net income:
Securities on deposit with state insurance departments	$ 45,200		$ 45,200
Business owned life insurance cost	33,000		33,000
Investment in unconsolidated subsidiaries	$ 385,631		$ 385,631		$ 367,757
Number of LPs / LLCs with investment ownership percent over 25% (in businesses) | Business	2		2
Total OTTI losses:	$ 0	$ (404)	$ (136)	$ (404)
Tax Credit Partnerships Almost 100% Ownership
Reclassifications from AOCI to net income:
Number of tax credit partnerships almost 100% ownership percentage | investment_interest	2		2
Investment in unconsolidated subsidiaries	$ 21,100		$ 21,100		25,000
Tax Credit Partnerships Almost 100% Ownership | Maximum
Reclassifications from AOCI to net income:
Investment ownership percentage	100.00%		100.00%
Tax Credit Partnerships Less Than 20% Ownership
Reclassifications from AOCI to net income:
Investment in unconsolidated subsidiaries	$ 35,000		$ 35,000		40,700
Tax Credit Partnerships Less Than 20% Ownership | Maximum
Reclassifications from AOCI to net income:
Investment ownership percentage	20.00%		20.00%
Other Limited Partnerships and Limited Liability Company, Greater Than 25% Ownership
Reclassifications from AOCI to net income:
Investment in unconsolidated subsidiaries	$ 37,500		$ 37,500		25,900
Other Limited Partnerships and Limited Liability Company Less than 25% Ownership
Reclassifications from AOCI to net income:
Investment in unconsolidated subsidiaries	288,800		288,800		$ 272,400
Fixed maturities
Reclassifications from AOCI to net income:
Required FAL deposit	129,600		129,600
Short-term investments
Reclassifications from AOCI to net income:
Required FAL deposit	$ 5,200		$ 5,200
Non government-backed
Reclassifications from AOCI to net income:
Debt securities in unrealized loss position (in securities) | Security	328		328		1,044
Debt securities in unrealized loss position as percentage of total debt securities held	15.50%		15.50%		50.60%
Issuers in unrealized loss position (in issuers) | Issuer	248		248		550
Single greatest unrealized loss position	$ 200		$ 200		$ 600
Second greatest unrealized loss position	200		200		$ 500
Corporate Debt
Reclassifications from AOCI to net income:
Total OTTI losses:	$ 0	$ (404)	$ (136)	$ (404)

Investments (Available-For-Sale

Investments (Available-For-Sale Fixed Maturities) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Reclassifications from AOCI to net income:
Amortized Cost	$ 2,188,547	$ 2,116,825
Gross Unrealized Gains	44,536	9,679
Gross Unrealized Losses	3,737	32,706
Estimated Fair Value	2,229,346	2,093,798
U.S. Treasury obligations
Reclassifications from AOCI to net income:
Amortized Cost	108,961	121,274
Gross Unrealized Gains	1,655	331
Gross Unrealized Losses	167	1,404
Estimated Fair Value	110,449	120,201
U.S. Government-sponsored enterprise obligations
Reclassifications from AOCI to net income:
Amortized Cost	29,035	35,758
Gross Unrealized Gains	141	25
Gross Unrealized Losses	29	429
Estimated Fair Value	29,147	35,354
State and municipal bonds
Reclassifications from AOCI to net income:
Amortized Cost	279,664	289,544
Gross Unrealized Gains	10,591	4,877
Gross Unrealized Losses	12	649
Estimated Fair Value	290,243	293,772
Corporate debt
Reclassifications from AOCI to net income:
Amortized Cost	1,283,074	1,244,577
Gross Unrealized Gains	26,112	3,328
Gross Unrealized Losses	2,322	24,430
Estimated Fair Value	1,306,864	1,223,475
Residential mortgage-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	181,183	184,463
Gross Unrealized Gains	2,140	814
Gross Unrealized Losses	1,065	4,039
Estimated Fair Value	182,258	181,238
Agency commercial mortgage-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	11,271	13,296
Gross Unrealized Gains	224	12
Gross Unrealized Losses	20	200
Estimated Fair Value	11,475	13,108
Other commercial mortgage-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	62,593	31,330
Gross Unrealized Gains	1,381	38
Gross Unrealized Losses	34	375
Estimated Fair Value	63,940	30,993
Other asset-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	232,766	196,583
Gross Unrealized Gains	2,292	254
Gross Unrealized Losses	88	1,180
Estimated Fair Value	$ 234,970	$ 195,657

Investments (Available-For-Sa_2

Investments (Available-For-Sale Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Reclassifications from AOCI to net income:
Amortized Cost	$ 2,188,547	$ 2,116,825
Total Fair Value	2,229,346	2,093,798
U.S. Treasury obligations
Reclassifications from AOCI to net income:
Amortized Cost	108,961	121,274
Due in one year or less	16,545
Due after one year through five years	71,405
Due after five years through ten years	22,076
Due after ten years	423
Total Fair Value	110,449	120,201
U.S. Government-sponsored enterprise obligations
Reclassifications from AOCI to net income:
Amortized Cost	29,035	35,758
Due in one year or less	5,391
Due after one year through five years	6,005
Due after five years through ten years	17,608
Due after ten years	143
Total Fair Value	29,147	35,354
State and municipal bonds
Reclassifications from AOCI to net income:
Amortized Cost	279,664	289,544
Due in one year or less	14,647
Due after one year through five years	116,908
Due after five years through ten years	133,199
Due after ten years	25,489
Total Fair Value	290,243	293,772
Corporate debt
Reclassifications from AOCI to net income:
Amortized Cost	1,283,074	1,244,577
Due in one year or less	154,196
Due after one year through five years	782,386
Due after five years through ten years	343,561
Due after ten years	26,721
Total Fair Value	1,306,864	1,223,475
Residential mortgage-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	181,183	184,463
Total Fair Value	182,258	181,238
Agency commercial mortgage-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	11,271	13,296
Total Fair Value	11,475	13,108
Other commercial mortgage-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	62,593	31,330
Total Fair Value	63,940	30,993
Other asset-backed securities
Reclassifications from AOCI to net income:
Amortized Cost	232,766	196,583
Total Fair Value	$ 234,970	$ 195,657

Investments (Investments Held i

Investments (Investments Held in a Loss Position) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Fair value
Fair Value	$ 419,713	$ 1,465,727
Less than 12 Months, Fair Value	59,440	634,958
More than 12 Months, Fair Value	360,273	830,769
Unrealized Loss
Unrealized Loss	3,737	32,706
Less than 12 Months, Unrealized Loss	549	9,823
More than 12 Months, Unrealized Loss	3,188	22,883
U.S. Treasury obligations
Fair value
Fair Value	34,577	97,969
Less than 12 Months, Fair Value	2,006	20,221
More than 12 Months, Fair Value	32,571	77,748
Unrealized Loss
Unrealized Loss	167	1,405
Less than 12 Months, Unrealized Loss	12	119
More than 12 Months, Unrealized Loss	155	1,286
U.S. Government-sponsored enterprise obligations
Fair value
Fair Value	9,372	33,677
Less than 12 Months, Fair Value	1,986	20,479
More than 12 Months, Fair Value	7,386	13,198
Unrealized Loss
Unrealized Loss	29	429
Less than 12 Months, Unrealized Loss	14	126
More than 12 Months, Unrealized Loss	15	303
State and municipal bonds
Fair value
Fair Value	4,589	63,094
Less than 12 Months, Fair Value	2,663	30,924
More than 12 Months, Fair Value	1,926	32,170
Unrealized Loss
Unrealized Loss	12	648
Less than 12 Months, Unrealized Loss	7	143
More than 12 Months, Unrealized Loss	5	505
Corporate debt
Fair value
Fair Value	242,882	938,651
Less than 12 Months, Fair Value	46,959	447,891
More than 12 Months, Fair Value	195,923	490,760
Unrealized Loss
Unrealized Loss	2,322	24,429
Less than 12 Months, Unrealized Loss	514	8,804
More than 12 Months, Unrealized Loss	1,808	15,625
Residential mortgage-backed securities
Fair value
Fair Value	81,377	157,120
Less than 12 Months, Fair Value	1,166	27,311
More than 12 Months, Fair Value	80,211	129,809
Unrealized Loss
Unrealized Loss	1,065	4,039
Less than 12 Months, Unrealized Loss	1	209
More than 12 Months, Unrealized Loss	1,064	3,830
Agency commercial mortgage-backed securities
Fair value
Fair Value	317	9,822
Less than 12 Months, Fair Value	0	4,566
More than 12 Months, Fair Value	317	5,256
Unrealized Loss
Unrealized Loss	20	200
Less than 12 Months, Unrealized Loss	0	22
More than 12 Months, Unrealized Loss	20	178
Other commercial mortgage-backed securities
Fair value
Fair Value	4,163	22,924
Less than 12 Months, Fair Value	0	13,348
More than 12 Months, Fair Value	4,163	9,576
Unrealized Loss
Unrealized Loss	34	375
Less than 12 Months, Unrealized Loss	0	164
More than 12 Months, Unrealized Loss	34	211
Other asset-backed securities
Fair value
Fair Value	42,436	142,470
Less than 12 Months, Fair Value	4,660	70,218
More than 12 Months, Fair Value	37,776	72,252
Unrealized Loss
Unrealized Loss	88	1,181
Less than 12 Months, Unrealized Loss	1	236
More than 12 Months, Unrealized Loss	$ 87	$ 945

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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Information regarding sales and purchases of available-for-sale securities
Proceeds from sales (exclusive of maturities and paydowns)	$ 61,800	$ 115,800	$ 93,300	$ 495,000
Purchases	$ 171,800	$ 184,600	$ 350,937	$ 552,451

Investments (Net Investment Inc

Investments (Net Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net Investment Income
Investment fees and expenses	$ (1,804)	$ (1,907)	$ (3,614)	$ (3,583)
Net investment income	23,539	22,384	46,357	44,411
Fixed maturities
Net Investment Income
Investment Income	18,275	17,506	35,792	34,586
Equities
Net Investment Income
Investment Income	4,990	4,998	9,813	9,865
Short-term investments, including Other
Net Investment Income
Investment Income	1,619	1,332	3,454	2,639
BOLI
Net Investment Income
Investment Income	$ 459	$ 455	$ 912	$ 904

Investments (Unconsolidated Sub

Investments (Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Unconsolidated Subsidiaries
Investment in unconsolidated subsidiaries	$ 385,631	$ 367,757
Qualified affordable housing project tax credit partnerships
Unconsolidated Subsidiaries
Investment in unconsolidated subsidiaries	56,067	65,677
Other tax credit partnerships
Unconsolidated Subsidiaries
Investment in unconsolidated subsidiaries	3,266	3,757
All other investments, primarily investment fund LPs/LLCs
Unconsolidated Subsidiaries
Investment in unconsolidated subsidiaries	$ 326,298	$ 298,323

Investments (Equity in Earnings

Investments (Equity in Earnings (Loss) of Unconsolidated Subsidiaries) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Losses recorded	$ 5,167	$ 5,612	$ 9,597	$ 9,712
Tax credits recognized	4,531	4,624	9,063	9,237
Losses recorded	302	1,506	491	3,382
Tax credits recognized	$ 103	$ 693	$ 206	$ 1,355

Investments (Net Realized Inves

Investments (Net Realized Investment Gains (Losses)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Marketable Securities [Line Items]
Total OTTI losses:	$ 0	$ (404)	$ (136)	$ (404)
Portion of OTTI losses recognized in other comprehensive income before taxes	0	0	87	0
Net impairment losses recognized in earnings	0	(404)	(49)	(404)
Gross realized gains, available-for-sale fixed maturities	1,006	438	1,374	4,902
Gross realized (losses), available-for-sale fixed maturities	(33)	(1,725)	(369)	(3,772)
Net realized gains (losses), trading fixed maturities	2	(73)	(25)	(73)
Net realized gains (losses), equity investments	9,218	3,488	11,008	12,706
Net realized gains (losses), other investments	198	402	577	1,090
Change in unrealized holding gains (losses), trading fixed maturities	265	(170)	475	(219)
Change in unrealized holding gains (losses), equity investments	(2,459)	745	29,932	(23,099)
Change in unrealized holding gains (losses), convertible securities, carried at fair value	1,110	90	3,006	(864)
Other	1	4	2	11
Total net realized investment gains (losses)	9,308	2,795	45,931	(9,722)
Corporate Debt
Marketable Securities [Line Items]
Total OTTI losses:	$ 0	$ (404)	(136)	$ (404)
Portion of OTTI losses recognized in other comprehensive income before taxes			$ 87

Investments (Credit Losses Reco

Investments (Credit Losses Recorded in Earnings) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Other than Temporary Impairment, Credit Losses Recognized in Earnings:
Balance beginning of period	$ 142	$ 1,313	$ 93	$ 1,313
No OTTI has been previously recognized	0	0	49	0
Balance ending of period	$ 142	$ 1,313	$ 142	$ 1,313

Retroactive Insurance Contrac_2

Retroactive Insurance Contracts (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Net premiums earned	$ 209,149	$ 223,591	$ 417,298	$ 410,750
Current Year Claims and Claims Adjustment Expense			354,466	337,116	$ 685,326
Net losses and loss adjustment expenses	168,440	161,728	328,195	291,515
Reserve for losses and loss adjustment expenses	$ 2,195,460	2,078,817	$ 2,195,460	2,078,817	2,119,847	$ 2,048,381
Retroactive Insurance Contract
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Net premiums earned				26,600
Current Year Claims and Claims Adjustment Expense				25,400	$ 25,400
Reserve for losses and loss adjustment expenses		$ 600		600
Retroactive Insurance Contract, Prospective Coverage
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Net premiums earned				7,900
Retroactive Insurance Contract, Retroactive Coverage
Liabilities for Guarantees on Long-Duration Contracts [Line Items]
Net premiums earned				$ 18,700

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income taxes receivable	$ 4.1	$ 3.5
Unrecognized tax benefits	4.5	4.2
Accrued liability for interest related to unrecognized tax benefits	$ 0.8	$ 0.6

Reserve for Losses and Loss A_3

Reserve for Losses and Loss Adjustment Expenses (Details) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2019USD ($)partition	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Liability for Claims and Claims Adjustment Expense [Line Items]
Minimum period for claims resolution (years)	5 years
Number of business partitions (in partitions) | partition	200
Summary of reserve for losses and loss adjustment expenses
Balance, beginning of year	$ 2,119,847	$ 2,048,381	$ 2,048,381
Less reinsurance recoverables on unpaid losses and loss adjustment expenses	343,820	335,585	335,585
Net balance, beginning of year	1,776,027	1,712,796	1,712,796
Net losses:
Current year	354,466	337,116	685,326
Favorable development of reserves established in prior years, net	(26,271)	(45,601)	(92,116)
Total	328,195	291,515	593,210
Paid related to:
Current year	(39,396)	(34,174)	(117,268)
Prior years	(221,378)	(215,488)	(412,711)
Total paid	(260,774)	(249,662)	(529,979)
Net balance, end of period	1,843,448	1,754,649	1,776,027
Plus reinsurance recoverables on unpaid losses and loss adjustment expenses	352,012	324,168	343,820
Balance, end of period	$ 2,195,460	2,078,817	2,119,847
Retroactive Insurance Contract
Net losses:
Current year		25,400	$ 25,400
Paid related to:
Balance, end of period		$ 600

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2019GBP (£)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019GBP (£)
Other Commitments [Line Items]
Repayments of Short-term Debt	$ 30,700	£ 24,200,000		$ (29,790)	$ 1,050
Operating expense	$ 34,661		$ 33,958	67,951	$ 66,422
Data analytics and services
Other Commitments [Line Items]
Purchase commitment, period (in years)	2 years	2 years
Annual fee	$ 4,800			4,800
Operating expense	1,300			2,300
Purchase obligation	6,300			6,300
Lloyd's Syndicates
Other Commitments [Line Items]
Required FAL deposit	$ 134,800			$ 134,800
Current lending capacity under revolving credit agreement | £						£ 30,000,000
Interest rate on revolving credit agreement (percent)	3.80%			3.80%		3.80%
Unused commitments to extend credit	$ 36,100			$ 36,100		£ 28,400,000
Commitment to provide capital | Lloyd's Syndicates
Other Commitments [Line Items]
Commitments total	200,000			200,000
Funding Commitments
Other Commitments [Line Items]
Commitments total	$ 263,900			$ 263,900

Leases (Narrative) (Details)

Leases (Narrative) (Details) $ in Millions	Jun. 30, 2019USD ($)
Lessee, Lease, Description [Line Items]
Renewal term	10 years
Excluded lease payments	$ 1.9
Lease term, not yet commenced	11 years
Minimum
Lessee, Lease, Description [Line Items]
Lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lease term	13 years

Leases (Lease Cost) (Details)

Leases (Lease Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Leases [Abstract]
Operating lease expense	$ 1,141	$ 1,261	$ 1,915	$ 2,528
Sublease income	(38)	(34)	(76)	(72)
Net lease expense	1,103	1,227	1,839	2,456
Rental income from owned properties	$ 600	$ 500	$ 1,200	$ 1,100

Leases (Supplemental Lease Info

Leases (Supplemental Lease Information) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019
Leases [Abstract]
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 757	$ 178
Operating lease ROU assets	20,374		$ 19,000
Operating lease liabilities	$ 21,131		$ 19,000
Weighted-average remaining lease term (in years)	8 years 10 months 20 days
Weighted-average discount rate	3.21%

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019
Leases [Abstract]
2019	$ 2,178
2020	3,883
2021	3,530
2022	2,648
2023	1,955
Thereafter	10,142
Total future minimum lease payments	24,336
Less: Imputed interest	3,205
Total operating lease liabilities	$ 21,131	$ 19,000

Debt (Details)

Debt (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Gross debt	$ 288,340,000	$ 289,064,000
Less debt issuance costs	1,123,000	1,307,000
Debt less debt issuance costs	287,217,000	287,757,000
Senior notes due 2023 | Senior notes due 2023
Debt Instrument [Line Items]
Gross debt	$ 250,000,000	$ 250,000,000
Stated interest rate on debt	5.30%	5.30%
Revolving credit agreement | Revolving credit agreement
Debt Instrument [Line Items]
Gross debt	$ 0	$ 0
Line of credit maximum borrowing capacity	250,000,000	250,000,000
Mortgage loans
Debt Instrument [Line Items]
Gross debt	$ 38,340,000	$ 39,064,000
Effective interest rate on debt	3.77%	4.10%
Mortgage loans | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate for debt	1.325%	1.325%

Derivatives (Narrative) (Detail

Derivatives (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Mortgage loans | LIBOR
Derivative [Line Items]
Basis spread on variable rate for debt	1.325%	1.325%
Interest Rate Cap
Derivative [Line Items]
Premium paid on derivative for right to receive cash payments	$ 2,000
Floor interest rate on derivative	2.35%
Cap interest rate on derivative	3.675%
Interest Rate Cap | Other assets
Derivative [Line Items]
Derivative asset, notional amount	$ 35,000	$ 35,000

Derivatives (Volume and Fair Va

Derivatives (Volume and Fair Value) (Details) - Interest Rate Cap - Other assets $ in Thousands	Jun. 30, 2019USD ($)derivative_instrument	Dec. 31, 2018USD ($)derivative_instrument
Derivative [Line Items]
Number of instruments (in derivative instruments) | derivative_instrument	1	1
Notional amount	$ 35,000	$ 35,000
Estimated fair value	$ 1,085	$ 1,884

Derivatives (Pre-tax Impact of

Derivatives (Pre-tax Impact of Change in Fair Value) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Interest Rate Cap | Interest expense
Derivative [Line Items]
Gains (Losses) Recognized in Income on Derivatives	$ (362)	$ 282	$ (799)	$ 857

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended				6 Months Ended
	Feb. 28, 2019	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized common stock (in shares)		100,000,000				100,000,000		100,000,000
Authorized preferred stock (in shares)		50,000,000				50,000,000		50,000,000
Quarterly dividend declared, per share (in usd per share)		$ 0.31	$ 0.31	$ 0.31	$ 0.31	$ 0.62	$ 0.62
Dividend declared						$ 33.3	$ 34.2
Total authorizations which remain available for use		$ 110				$ 110
Common shares acquired (in shares)						0	0
Bonus compensation shares issued (in shares)	2,000
Non-credit loss, net of tax		$ 0.2				$ 0.2		$ 0.1
Accumulated Other Comprehensive Income (Loss)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reclassification from AOCI to retained earnings for stranded tax effects							$ 3.4
Retained Earnings
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reclassification from AOCI to retained earnings for stranded tax effects						$ (3.4)
Restricted Share Units (in shares)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards in period (in shares)	109,000
Fair value of each unit awarded (in usd per share)	$ 40.18
Award vesting period						3 years
Shares issued in period for share-based compensation (in shares)	64,500
Performance Share Units (in shares)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards in period (in shares)	25,000
Shares issued in period for share-based compensation (in shares)	34,300
Performance Share Units (in shares) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award payout rate						50.00%
Performance Share Units (in shares) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award payout rate						200.00%
Level at which performance shares were granted in 2016 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award payout rate						95.00%

Shareholders' Equity (Share-bas

Shareholders' Equity (Share-based Compensation Expense and Related Tax Benefits) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Equity [Abstract]
Share-based compensation expense	$ 1,092	$ 1,615	$ 2,320	$ 2,517
Related tax benefits	$ 229	$ 339	$ 487	$ 529

Shareholders' Equity (AOCI Recl

Shareholders' Equity (AOCI Reclassification) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Reclassifications from AOCI to net income:
Tax effect, calculated using the 21% federal statutory tax rate	$ (205)	$ 355	$ (201)	$ (153)
Net reclassification adjustments	769	(1,336)	756	573
Deferred tax expense (benefit) included in OCI	6,177	(2,185)	12,982	(9,245)
Realized investment gains (losses)
Reclassifications from AOCI to net income:
Reclassifications from AOCI to net income:	$ 974	$ (1,691)	$ 957	$ 726

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Variable interest entity, not primary beneficiary | Equity investments
Variable Interest Entity [Line Items]
VIE interests carrying value	$ 303.2	$ 285.8

Earnings Per Share (Details)

Earnings Per Share (Details) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average number of common shares outstanding, basic (in shares)	53,750,000	53,610,000	53,716,000	53,567,000
Weighted average number of common shares outstanding, diluted (in shares)	53,828,000	53,741,000	53,818,000	53,716,000
Effect of dilutive shares on earnings per share (in usd per share)	$ 0	$ 0	$ 0	$ 0
Antidilutive shares excluded from computation of earnings per share (in shares)	0	8,000	0	8,000
Restricted Share Units (in shares)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive securities (in shares)	53,000	69,000	67,000	75,000
Performance Share Units (in shares)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive securities (in shares)	10,000	42,000	20,000	54,000
Purchase Match Units (in shares)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dilutive securities (in shares)	15,000	20,000	15,000	20,000

Segment Information (Narrative)

Segment Information (Narrative) (Details)	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018
Workers' Compensation Insurance
Segment Reporting Information [Line Items]
Worker's compensation SPC percentage ceded	100.00%
Syndicate 1729
Segment Reporting Information [Line Items]
Proportion of capital provided to support Lloyd's Syndicate 1729		61.00%	62.00%
Syndicate 6131
Segment Reporting Information [Line Items]
Proportion of capital provided to support Lloyd's Syndicate 1729				100.00%

Segment Information (Financial

Segment Information (Financial Data by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Net premiums earned	$ 209,149	$ 223,591	$ 417,298	$ 410,750
Net investment income	23,539	22,384	46,357	44,411
Equity in earnings (loss) of unconsolidated subsidiaries	(5,152)	5,380	(5,962)	7,019
Net realized gains (losses)	9,308	2,795	45,931	(9,722)
Other income (expense)	2,777	2,044	4,872	4,767
Net losses and loss adjustment expenses	(168,440)	(161,728)	(328,195)	(291,515)
Underwriting, policy acquisition and operating expenses	(62,708)	(59,611)	(124,100)	(116,969)
Segregated portfolio cells dividend expense (income)	(7,033)	2,785	(2,246)	4,532
Interest expense	(4,247)	(3,958)	(8,576)	(7,663)
Income tax benefit (expense)	277	311	(6,685)	3,733
Net income	11,536	28,423	43,186	40,279
Depreciation and amortization, net of accretion	4,617	4,957	9,653	11,036
Specialty P&C
Segment Reporting Information [Line Items]
Net premiums earned	126,011	142,619	250,079	257,567
Workers' Compensation Insurance
Segment Reporting Information [Line Items]
Net premiums earned	46,574	45,234	92,512	87,934
Segregated Portfolio Cell Reinsurance
Segment Reporting Information [Line Items]
Net premiums earned	19,284	18,248	38,787	35,284
Lloyd's Syndicates
Segment Reporting Information [Line Items]
Net premiums earned	17,280	17,490	35,920	29,965
Operating segments | Specialty P&C
Segment Reporting Information [Line Items]
Net premiums earned	126,011	142,619	250,079	257,567
Other income (expense)	1,470	1,262	2,680	2,519
Net losses and loss adjustment expenses	106,017	(110,856)	(213,675)	194,380
Underwriting, policy acquisition and operating expenses	29,863	(27,922)	(59,480)	55,902
Net income	(8,399)	5,103	(20,396)	9,804
Depreciation and amortization, net of accretion	1,623	1,761	3,359	3,628
Operating segments | Workers' Compensation Insurance
Segment Reporting Information [Line Items]
Net premiums earned	46,574	45,234	92,512	87,934
Other income (expense)	725	602	1,454	1,453
Net losses and loss adjustment expenses	30,625	(29,319)	(61,068)	57,143
Underwriting, policy acquisition and operating expenses	14,368	(13,107)	(28,559)	26,137
Net income	2,306	3,410	4,339	6,107
Depreciation and amortization, net of accretion	959	958	1,936	1,914
Operating segments | Segregated Portfolio Cell Reinsurance
Segment Reporting Information [Line Items]
Net premiums earned	19,284	18,248	38,787	35,284
Net investment income	368	373	815	729
Net realized gains (losses)	(94)	(457)	2,047	(930)
Other income (expense)	135	60	221	90
Net losses and loss adjustment expenses	19,973	(9,048)	(30,719)	(19,001)
Underwriting, policy acquisition and operating expenses	5,905	(5,440)	(11,138)	(10,554)
Segregated portfolio cells dividend expense (income)	7,033	2,785	(2,246)	(4,532)
Net income	848	951	2,259	1,086
Depreciation and amortization, net of accretion	(32)	149	14	310
Operating segments | Lloyd's Syndicates
Segment Reporting Information [Line Items]
Net premiums earned	17,280	17,490	35,920	29,965
Net investment income	1,199	836	2,205	1,587
Net realized gains (losses)	262	(252)	440	(306)
Other income (expense)	32	(436)	(114)	(105)
Net losses and loss adjustment expenses	11,825	(12,505)	(22,733)	20,991
Underwriting, policy acquisition and operating expenses	7,564	(8,060)	(16,033)	(15,306)
Segregated portfolio cells dividend expense (income)	0
Income tax benefit (expense)	(304)			6
Net income	(312)	(2,927)	(315)	(5,162)
Depreciation and amortization, net of accretion	(4)	(2)	(7)	(3)
Operating segments | Corporate
Segment Reporting Information [Line Items]
Net investment income	21,972	21,175	43,337	42,095
Equity in earnings (loss) of unconsolidated subsidiaries	(5,152)	5,380	(5,962)	7,019
Net realized gains (losses)	9,140	3,504	43,444	(8,486)
Other income (expense)	833	1,095	1,738	2,037
Underwriting, policy acquisition and operating expenses	5,426	(5,621)	(9,997)	10,297
Segregated portfolio cells dividend expense (income)			0
Interest expense	4,247	(3,958)	(8,576)	7,663
Income tax benefit (expense)	27	311	(6,685)	3,739
Net income	17,093	21,886	57,299	28,444
Depreciation and amortization, net of accretion	2,071	2,091	4,351	5,187
Inter-segment Eliminations
Segment Reporting Information [Line Items]
Other income (expense)	(418)	(539)	(1,107)	(1,227)
Underwriting, policy acquisition and operating expenses	(418)	539	1,107	(1,227)
Segregated portfolio cells dividend expense (income)	0
Net income	$ 0	$ 0	$ 0	$ 0

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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Segment net premiums earned	$ 209,149	$ 223,591	$ 417,298	$ 410,750
Specialty P&C
Segment Reporting Information [Line Items]
Ceded premiums earned	(19,158)	(18,977)	(38,107)	(37,727)
Segment net premiums earned	126,011	142,619	250,079	257,567
Specialty P&C | Healthcare professional liability
Segment Reporting Information [Line Items]
Gross premiums earned	128,893	146,208	256,914	264,892
Specialty P&C | Legal professional liability
Segment Reporting Information [Line Items]
Gross premiums earned	6,708	6,489	13,268	12,880
Specialty P&C | Medical technology liability
Segment Reporting Information [Line Items]
Gross premiums earned	8,356	8,780	16,658	17,292
Specialty P&C | Other
Segment Reporting Information [Line Items]
Gross premiums earned	1,212	119	1,346	230
Workers' Compensation Insurance
Segment Reporting Information [Line Items]
Ceded premiums earned	(24,308)	(24,244)	(48,646)	(47,158)
Segment net premiums earned	46,574	45,234	92,512	87,934
Workers' Compensation Insurance | Traditional business
Segment Reporting Information [Line Items]
Gross premiums earned	50,036	48,830	99,321	95,063
Workers' Compensation Insurance | Alternative market business
Segment Reporting Information [Line Items]
Gross premiums earned	20,846	20,648	41,837	40,029
Segregated Portfolio Cell Reinsurance
Segment Reporting Information [Line Items]
Ceded premiums earned	(2,414)	(2,177)	(4,851)	(4,310)
Segment net premiums earned	19,284	18,248	38,787	35,284
Segregated Portfolio Cell Reinsurance | Healthcare professional liability
Segment Reporting Information [Line Items]
Gross premiums earned	1,349	1,228	2,672	2,558
Segregated Portfolio Cell Reinsurance | Other
Segment Reporting Information [Line Items]
Gross premiums earned	120	0	240	0
Segregated Portfolio Cell Reinsurance | Workers' compensation
Segment Reporting Information [Line Items]
Gross premiums earned	20,229	19,197	40,726	37,036
Lloyd's Syndicates
Segment Reporting Information [Line Items]
Gross premiums earned	21,997	19,273	45,825	37,240
Ceded premiums earned	(4,717)	(1,783)	(9,905)	(7,275)
Segment net premiums earned	$ 17,280	17,490	35,920	29,965
Premiums assumed under Quota Share Agreement		$ 1,400	$ 100	$ 3,300