Mercury General (MCY) 10-Q 31 Oct 17 2017 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Oct. 26, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Entity Registrant Name	MERCURY GENERAL CORP
Entity Central Index Key	64,996
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		55,332,077

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
ASSETS
Fixed maturity securities (amortized cost $2,776,887; $2,795,410)	$ 2,841,736	$ 2,814,553
Equity securities (cost $479,410; $331,770)	519,194	357,327
Short-term investments (cost $366,512; $375,700)	366,402	375,680
Total investments	3,727,332	3,547,560
Cash	284,639	220,318
Receivables:
Premium	485,868	459,152
Accrued investment income	42,535	41,205
Other	18,041	24,635
Total receivables	546,444	524,992
Deferred policy acquisition costs	201,919	200,826
Fixed assets (net of accumulated depreciation $335,477; $319,429)	144,478	155,910
Deferred income taxes	30,339	45,277
Goodwill	42,796	42,796
Other intangible assets, net	21,611	25,625
Other assets	26,041	25,414
Total assets	5,025,599	4,788,718
Liabilities
Loss and loss adjustment expense reserves	1,372,164	1,290,248
Unearned premiums	1,119,973	1,074,437
Notes payable	371,236	320,000
Accounts payable and accrued expenses	130,825	112,334
Current income taxes	13,173	9,962
Other liabilities	242,037	229,335
Total liabilities	3,249,408	3,036,316
Commitments and contingencies
Shareholders’ equity:
Common stock without par value or stated value: Authorized 70,000 shares; issued and outstanding 55,332; 55,289	97,523	95,529
Retained earnings	1,678,668	1,656,873
Total shareholders’ equity	1,776,191	1,752,402
Total liabilities and shareholders’ equity	$ 5,025,599	$ 4,788,718

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Amortized cost on fixed maturities trading investments	$ 2,776,887	$ 2,795,410
Cost - equity security trading investments	479,410	331,770
Cost - short-term investments	366,512	375,700
Fixed assets, accumulated depreciation	$ 335,477	$ 319,429
Common Stock
Common stock, no par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	70,000	70,000
Common stock, shares issued (in shares)	55,332	55,289
Common stock, shares outstanding (in shares)	55,332	55,289

Consolidated Statements Of Oper

Consolidated Statements Of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
Net premiums earned	$ 801,205	$ 790,850	$ 2,388,641	$ 2,337,256
Net investment income	30,988	30,371	94,058	91,440
Net realized investment gains (losses)	20,718	(15,465)	66,334	54,973
Other	5,446	2,406	9,675	6,416
Total revenues	858,357	808,162	2,558,708	2,490,085
Expenses:
Losses and loss adjustment expenses	595,290	576,316	1,790,550	1,765,484
Policy acquisition costs	136,290	140,203	416,728	421,685
Other operating expenses	64,339	59,006	182,959	178,000
Interest	4,191	1,012	10,873	2,922
Total expenses	800,110	776,537	2,401,110	2,368,091
Income before income taxes	58,247	31,625	157,598	121,994
Income tax expense	11,762	4,695	32,500	22,868
Net income	$ 46,485	$ 26,930	$ 125,098	$ 99,126
Net income per share:
Basic (in dollars per share)	$ 0.84	$ 0.49	$ 2.26	$ 1.79
Diluted (in dollars per share)	$ 0.84	$ 0.49	$ 2.26	$ 1.79
Weighted average shares outstanding:
Basic (in shares)	55,324	55,259	55,311	55,238
Diluted (in shares)	55,334	55,328	55,323	55,304
Dividends paid per share (in dollars per share)	$ 0.6225	$ 0.6200	$ 1.8675	$ 1.8600

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 125,098	$ 99,126
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	41,617	39,580
Net realized investment gains	(66,334)	(54,973)
Increase in premiums receivable	(26,716)	(37,965)
Gain on sale of fixed assets	(3,307)	0
Changes in current and deferred income taxes	18,149	22,494
Increase in deferred policy acquisition costs	(1,093)	(4,995)
Increase in loss and loss adjustment expense reserves	81,916	97,865
Increase in unearned premiums	45,536	52,838
Increase (decrease) in accounts payable and accrued expenses	19,260	(2,172)
Share-based compensation	60	107
Other, net	42,279	1,910
Net cash provided by operating activities	276,465	213,815
CASH FLOWS FROM INVESTING ACTIVITIES
Fixed maturities available-for-sale in nature: Purchases	(527,418)	(742,671)
Fixed maturities available-for-sale in nature: Sales	86,970	230,909
Fixed maturities available-for-sale in nature: Calls or maturities	436,479	421,737
Equity securities available for sale in nature:
Equity securities available for sale in nature: Purchases	(626,097)	(535,155)
Equity securities available for sale in nature: Sales	480,293	499,126
Equity securities available for sale in nature: Calls	7,100	0
Changes in securities payable and receivable	(22,474)	17,272
Changes in short-term investments and purchased options	11,169	(24,366)
Purchase of fixed assets	(14,275)	(12,874)
Sale of fixed assets	6,239	3
Other, net	0	3,186
Net cash used in investing activities	(162,014)	(142,833)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid to shareholders	(103,303)	(102,783)
Employee taxes paid with shares related to share-based compensation	0	(3,269)
Proceeds from stock options exercised	2,162	706
Net proceeds from issuance of senior notes	371,011	0
Payoff of principal on loan and credit facilities	(320,000)	0
Net cash used in financing activities	(50,130)	(105,346)
Net increase (decrease) in cash	64,321	(34,364)
Cash:
Beginning of the year	220,318	264,221
End of period	284,639	229,857
SUPPLEMENTAL CASH FLOW DISCLOSURE
Interest paid	9,863	2,797
Income taxes paid	$ 14,350	$ 374

General

General	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	General Consolidation and Basis of Presentation The interim consolidated financial statements include the accounts of Mercury General Corporation and its subsidiaries (referred to herein collectively as the “Company”). For the list of the Company’s subsidiaries, see Note 1. Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 . These interim financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”), which differ in some respects from those filed in reports to insurance regulatory authorities. The financial data of the Company included herein are unaudited. In the opinion of management, all material adjustments of a normal recurring nature have been made to present fairly the Company’s financial position at September 30, 2017 and the results of operations and cash flows for the periods presented. All intercompany transactions and balances have been eliminated. Certain financial information that is normally included in annual financial statements prepared in accordance with GAAP, but that is not required for interim reporting purposes, has been omitted from the accompanying interim consolidated financial statements and related notes. Readers are urged to review the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 for more complete descriptions and discussions. Operating results and cash flows for the nine months ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 . Certain prior period amounts have been reclassified to conform to the current period presentation. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates require the Company to apply complex assumptions and judgments, and often the Company must make estimates about the effects of matters that are inherently uncertain and will likely change in subsequent periods. The most significant assumptions in the preparation of these consolidated financial statements relate to reserves for losses and loss adjustment expenses. Actual results could differ from those estimates. See Note 1. Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 . Earnings per Share Potentially dilutive securities representing approximately 22,000 and 29,000 shares of common stock for the three and nine months ended September 30, 2016 , respectively, were excluded from the computation of diluted earnings per common share because their effect would have been anti-dilutive. There were no potentially dilutive securities with anti-dilutive effect for the three and nine months ended September 30, 2017 . Deferred Policy Acquisition Costs Deferred policy acquisition costs consist of commissions paid to outside agents, premium taxes, salaries, and certain other underwriting costs that are incremental or directly related to the successful acquisition of new and renewal insurance contracts and are amortized over the life of the related policy in proportion to premiums earned. Deferred policy acquisition costs are limited to the amount that will remain after deducting from unearned premiums and anticipated investment income, the estimated losses and loss adjustment expenses, and the servicing costs that will be incurred as premiums are earned. The Company’s deferred policy acquisition costs are further limited by excluding those costs not directly related to the successful acquisition of insurance contracts. Deferred policy acquisition cost amortization was $136.3 million and $140.2 million for the three months ended September 30, 2017 and 2016 , respectively, and $416.7 million and $421.7 million for the nine months ended September 30, 2017 and 2016 , respectively. The Company does not defer advertising expenditures but expenses them as incurred. The Company recorded net advertising expense of approximately $32.0 million and $34.1 million for the nine months ended September 30, 2017 and 2016 , respectively. Fixed Assets In August 2017, the Company completed the sale of approximately six acres of land located in Brea, California (the "Property"), for a total sale price of approximately $12.2 million . Approximately $5.7 million of the total sale price was received in the form of a promissory note (the "Note") and the remainder in cash. The Note is secured by a first trust deed and an assignment of rents on the Property, and bears interest at an annual rate of 3.5% , payable in monthly installments. The Note matures in August 2020. Interest earned on the Note is recognized in other revenues in the consolidated statements of operations. The Company recognized a gain of approximately $3.3 million on the sale transaction, which is included in other revenues in the consolidated statements of operations.

Recently Issued Accounting Stan

Recently Issued Accounting Standards	9 Months Ended
	Sep. 30, 2017
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recently Issued Accounting Standards	Recently Issued Accounting Standards In May 2017, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2017-09, " Compensation - Stock Compensation (Topic 718), Scope of Modification Accounting. " ASU 2017-09 provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting in Topic 718. ASU 2017-09 will be effective for the Company beginning January 1, 2018 with early adoption permitted. The Company does not anticipate that ASU 2017-09 will have a material impact on its consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU 2017-04, " Intangibles - Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment. " ASU 2017-04 removes the requirement to compare the implied fair value of goodwill with its carrying amount as part of Step 2 of the goodwill impairment test and requires an entity to recognize an impairment charge for the amount by which the carrying amount of a reporting unit exceeds its fair value. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. ASU 2017-04 will be effective for the Company beginning January 1, 2020 with early adoption permitted. The Company does not anticipate that ASU 2017-04 will have a material impact on its consolidated financial statements and related disclosures. In October 2016, the FASB issued ASU 2016-16, " Income Taxes (Topic 740), Intra-Entity Transfers of Assets Other Than Inventory. " ASU 2016-16 requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Current GAAP prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. ASU 2016-16 will be effective for the Company beginning January 1, 2018. The Company is evaluating the impact that ASU 2016-16 will have on its consolidated financial statements and related disclosures. In August 2016, the FASB issued ASU 2016-15, " Classification of Certain Cash Receipts and Cash Payments (Topic 230). " The new guidance is intended to reduce diversity in how certain transactions are classified in the consolidated statement of cash flows. ASU 2016-15 will be effective for the Company beginning January 1, 2018. The Company is evaluating the impact that ASU 2016-15 will have on its consolidated financial statements and related disclosures. In June 2016, the FASB issued ASU 2016-13, " Financial Instruments - Credit Losses (Topic 326). " The amendments in this ASU replace the "incurred loss" methodology for recognizing credit losses with a methodology that reflects expected credit losses and requires consideration of a broader range of information including past events, current conditions and reasonable and supportable forecasts that affect the collectibility of reported amounts of financial assets that are not accounted for at fair value through net income, such as loans, certain debt securities, trade receivables, net investment in leases, off-balance sheet credit exposures and reinsurance receivables. Under the current GAAP incurred loss methodology, recognition of the full amount of credit losses is generally delayed until the loss is probable of occurring. Current GAAP restricts the ability to record credit losses that are expected, but do not yet meet the probability threshold. ASU 2016-13 will be effective for the Company beginning with the first quarter ending March 31, 2020. While the Company is in the process of evaluating the impact of ASU 2016-13, it does not expect this ASU to have a material impact on its consolidated financial statements and related disclosures as most of its financial instruments with potential exposure to material credit losses are accounted for at fair value through net income. In March 2016, the FASB issued ASU 2016-09, " Compensation - Stock Compensation (Topic 718) ," which simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The Company adopted ASU 2016-09 for the quarter ended March 31, 2017. As a result of the adoption, the Company recognizes excess tax benefits in its provision for income taxes rather than paid-in capital. Additional amendments to accounting for income taxes and minimum statutory withholding tax requirements had no impact to retained earnings as of January 1, 2017, where the cumulative effect of these changes are required to be recorded. The Company elected to continue to estimate forfeitures expected to occur to determine the amount of compensation cost to be recognized in each period. The Company also elected to apply the presentation requirements for cash flows related to excess tax benefits retrospectively to all periods presented, which resulted in an increase to both net cash provided by operating activities and net cash used in financing activities of approximately $995,000 for the nine months ended September 30, 2016 . The adoption of the presentation requirements for cash flows related to employee taxes paid with shares resulted in an increase to both net cash provided by operating activities and net cash used in financing activities of approximately $3,270,000 for the nine months ended September 30, 2016 . In February 2016, the FASB issued ASU 2016-02, " Leases (Topic 842) ," which supersedes the guidance in Accounting Standards Codification ("ASC") 840, "Leases." ASU 2016-02 requires a lessee to recognize lease assets and lease liabilities resulting from all leases. ASU 2016-02 retains the distinction between a finance lease and an operating lease. Lessor accounting is largely unchanged from ASC 840. ASU 2016-02 will be effective for the Company beginning January 1, 2019. However, in transition, the Company will be required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. While the Company is in the process of evaluating the impact of ASU 2016-02, it does not expect this ASU to have a material impact on its consolidated financial statements, except for recognizing lease assets and lease liabilities for its operating leases. The Company's lease obligations under various non-cancellable operating lease agreements amounted to approximately $27,000,000 at December 31, 2016. In January 2016, the FASB issued ASU 2016-01, " Financial Instruments-Overall (Subtopic 825-10) , Recognition and Measurement of Financial Assets and Financial Liabilities. " The amendments in this ASU address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU 2016-01: (1) requires equity investments (except those accounted for under the equity method or those that result in the consolidation of the investee) to be measured at fair value with changes in the fair value recognized in net income; (2) simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; (3) eliminates the requirement for public business entities to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet; (4) requires the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (5) requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the notes to the financial statements; and (6) clarifies that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity’s other deferred tax assets. ASU 2016-01 will be effective for the Company beginning January 1, 2018. The Company does not anticipate that ASU 2016-01 will have a material impact on its consolidated financial statements and related disclosures. In May 2014, the FASB issued ASU 2014-09, " Revenue from Contracts with Customers (Topic 606). " ASU 2014-09 requires entities to apply a five-step model to determine the amount and timing of revenue recognition. The model specifies, among other criteria, that revenue should be recognized when an entity transfers control of goods or services to a customer in the amount to which the entity expects to be entitled. In August 2015, the FASB issued ASU 2015-14, " Revenue from Contracts with Customers (Topic 606), Deferral of the Effective Date ," which deferred the effective date of ASU 2014-09 for the Company to January 1, 2018. Subsequently, the FASB has issued additional ASUs on Topic 606 that do not change the core principle of the guidance in ASU 2014-09 but merely clarify certain aspects of it. The additional ASUs will also be effective for the Company beginning January 1, 2018. Two methods of transition are permitted upon adoption: full retrospective and modified retrospective. The Company is evaluating both methods of transition and it is currently anticipated that a modified retrospective adoption approach will be used. However, as the accounting for insurance contracts is outside of the scope of ASU 2014-09, the Company does not expect the adoption of this ASU to have a material impact on its consolidated financial statements and related disclosures.

Financial Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2017
Financial Instruments, Owned, at Fair Value [Abstract]
Financial Instruments	Financial Instruments Financial instruments recorded in the consolidated balance sheets include investments, note receivable, other receivables, options sold, total return swaps, accounts payable, and secured and unsecured notes payable. Due to their short-term maturities, the carrying values of other receivables and accounts payable approximate their fair values. All investments are carried at fair value in the consolidated balance sheets. The following table presents the fair values of financial instruments: September 30, 2017 December 31, 2016 (Amounts in thousands) Assets Investments $ 3,727,332 $ 3,547,560 Note receivable 5,585 — Total return swaps — 667 Liabilities Total return swaps $ 1,589 $ 765 Options sold 146 20 Secured notes — 140,000 Unsecured notes 385,733 180,000 Investments The Company applies the fair value option to all fixed maturity and equity securities and short-term investments at the time an eligible item is first recognized. The cost of investments sold is determined on a first-in and first-out method and realized gains and losses are included in net realized investment gains (losses) i n the Company's consolidated statements of operations . See Note 4. Fair Value Option for additional information. In the normal course of investing activities, the Company either forms or enters into relationships with variable interest entities ("VIEs"). A VIE is an entity that either has investors that lack certain essential characteristics of a controlling financial interest, such as simple majority kick-out rights, or lacks sufficient funds to finance its own activities without financial support provided by other entities. The Company performs ongoing qualitative assessments of the VIEs to determine whether the Company has a controlling financial interest in the VIE and therefore is the primary beneficiary. The Company is deemed to have a controlling financial interest when it has both the ability to direct the activities that most significantly impact the economic performance of the VIE and the obligation to absorb losses or right to receive benefits from the VIE that could potentially be significant to the VIE. Based on the Company's assessment, if it determines it is the primary beneficiary, the Company consolidates the VIE in its consolidated financial statements. The Company forms special purpose investment vehicles to facilitate its investment activities involving derivative instruments such as total return swaps, or limited partnerships such as private equity funds. These special purpose investment vehicles are consolidated VIEs as the Company has determined it is the primary beneficiary of such VIEs. Creditors have no recourse against the Company in the event of default by these VIEs. The Company had no implied or unfunded commitments to these VIEs at September 30, 2017 and December 31, 2016 . The Company's financial or other support provided to these VIEs and its loss exposure are limited to its collateral and original investment. The Company also invests directly in limited partnerships such as private equity funds. These investments are non-consolidated VIEs as the Company has determined it is not the primary beneficiary. The Company's maximum exposure to loss is limited to the total carrying value that is included in equity securities in the Company's consolidated balance sheets. At September 30, 2017 and December 31, 2016 , the Company had no outstanding unfunded commitments to these VIEs whereby the Company may be called by the partnerships during the commitment period to fund the purchase of new investments and the expenses of the partnerships. Note Receivable Note receivable was recognized as part of the sale of land in August 2017 (See Note 1. General for additional information on the sale transaction). The Company elected to apply the fair value option to this security at the time it was first recognized. The fair value of note receivable is included in other assets in the Company's consolidated balance sheets, while the changes in fair value of note receivable are included in net realized investment gains or losses i n the Company's consolidated statements of operations . Options Sold The Company writes covered call options through listed and over-the-counter exchanges. When the Company writes an option, an amount equal to the premium received by the Company is recorded as a liability and is subsequently adjusted to the current fair value of the option written. Premiums received from writing options that expire unexercised are treated by the Company as realized gains from investments on the expiration date. If a call option is exercised, the premium is added to the proceeds from the sale of the underlying security or currency in determining whether the Company has realized a gain or loss. The Company, as writer of an option, bears the market risk of an unfavorable change in the price of the security underlying the written option. Liabilities for covered call options are included in other liabilities in the Company's consolidated balance sheets. Total Return Swaps The fair values of the total return swaps reflect the estimated amounts that, upon termination of the contracts, would be received for selling an asset or paid to transfer a liability in an orderly transaction. Secured Notes The fair values of the Company’s $120 million secured note and $20 million secured note at December 31, 2016 approximate their carrying values. Unsecured Notes The fair value of the Company’s publicly traded $375 million unsecured note at September 30, 2017 was obtained from a third party pricing service. The fair value of the Company's $180 million unsecured note at December 31, 2016 approximates its carrying value. For additional disclosures regarding methods and assumptions used in estimating fair values, see Note 5. Fair Value Measurements.

Fair Value Option

Fair Value Option	9 Months Ended
	Sep. 30, 2017
Fair Value Option [Abstract]
Fair Value Option	Fair Value Option The Company applies the fair value option to all fixed maturity and equity investment securities and short-term investments at the time an eligible item is first recognized. In addition, the Company elected to apply the fair value option to note receivable recognized as part of the sale of land in August 2017 (See Note 1. General for additional information on the sale transaction). The primary reasons for electing the fair value option were simplification and cost-benefit considerations as well as the expansion of the use of fair value measurement by the Company consistent with the long-term measurement objectives of the FASB for accounting for financial instruments. Gains or losses due to changes in fair value of financial instruments measured at fair value pursuant to application of the fair value option are included in net realized investment gains or losses in the Company’s consolidated statements of operations. Interest and dividend income on investment holdings are recognized on an accrual basis at each measurement date and are included in net investment income in the Company’s consolidated statements of operations, while interest earned on note receivable is included in other revenues in the Company’s consolidated statements of operations. The following table presents gains (losses) due to changes in fair value of investments and note receivable that are measured at fair value pursuant to the application of the fair value option: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (Amounts in thousands) Fixed maturity securities $ 9,796 $ (19,521 ) $ 45,705 $ 20,913 Equity securities 7,765 (2,143 ) 14,227 13,430 Short-term investments 150 532 (89 ) 184 Total investments 17,711 (21,132 ) 59,843 34,527 Note receivable (103 ) — (103 ) — Total gains (losses) $ 17,608 $ (21,132 ) $ 59,740 $ 34,527

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2017
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Fair Value Measurement	Fair Value Measurements The Company employs a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The fair value of a financial instrument is the amount 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 using the exit price. Accordingly, when market observable data are not readily available, the Company’s own assumptions are used to reflect those that market participants would be presumed to use in pricing the asset or liability at the measurement date. Assets and liabilities recorded at fair value on the consolidated balance sheets are categorized based on the level of judgment associated with inputs used to measure their fair values and the level of market price observability, as follows: Level 1 Unadjusted quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Level 2 Pricing inputs are other than quoted prices in active markets, which are based on the following: • Quoted prices for similar assets or liabilities in active markets; • Quoted prices for identical or similar assets or liabilities in non-active markets; or • Either directly or indirectly observable inputs as of the reporting date. Level 3 Pricing inputs are unobservable and significant to the overall fair value measurement, and the determination of fair value requires significant management judgment or estimation. In certain cases, inputs used to measure fair value may fall into different levels of the fair value hierarchy. In such cases, the level in the fair value hierarchy within which the fair value measurement in its entirety falls has been determined based on the lowest level input that is significant to the fair value measurement in its entirety. Thus, a Level 3 fair value measurement may include inputs that are observable (Level 1 or Level 2) and unobservable (Level 3). The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and consideration of factors specific to the asset or liability. The Company uses prices and inputs that are current as of the measurement date, including during periods of market disruption. In periods of market disruption, the ability to observe prices and inputs may be reduced for many instruments. This condition could cause an instrument to be reclassified from Level 1 to Level 2, or from Level 2 to Level 3. The Company recognizes transfers between levels at either the actual date of the event or a change in circumstances that caused the transfer. Summary of Significant Valuation Techniques for Financial Assets and Financial Liabilities The Company’s fair value measurements are based on the market approach, which utilizes market transaction data for the same or similar instruments. The Company obtained unadjusted fair values on 97.9% of its investment portfolio from an independent pricing service. For 0.2% of its investment portfolio, classified as Level 3, the Company obtained specific unadjusted broker quotes based on net fund value and, to a lesser extent, unobservable inputs from at least one knowledgeable outside security broker to determine the fair value as of September 30, 2017 . Level 1 measurements - Fair values of financial assets and financial liabilities are obtained from an independent pricing service, and are based on unadjusted quoted prices for identical assets or liabilities in active markets. Additional pricing services and closing exchange values are used as a comparison to ensure that reasonable fair values are used in pricing the investment portfolio. U.S. government bonds and agencies/Short-term bonds : Valued using unadjusted quoted market prices for identical assets in active markets. Common stock : Comprised of actively traded, exchange listed U.S. and international equity securities and valued based on unadjusted quoted prices for identical assets in active markets. Money market instruments : Valued based on unadjusted quoted prices for identical assets in active markets. Options sold : Comprised of free-standing exchange listed derivatives that are actively traded and valued based on unadjusted quoted prices for identical instruments in active markets. Level 2 measurements - Fair values of financial assets and financial liabilities are obtained from an independent pricing service or outside brokers, and are based on prices for similar assets or liabilities in active markets or valuation models whose inputs are observable, directly or indirectly, for substantially the full term of the asset or liability. Additional pricing services are used as a comparison to ensure reliable fair values are used in pricing the investment portfolio. Municipal securities : Valued based on models or matrices using inputs such as quoted prices for identical or similar assets in active markets. Mortgage-backed securities : Comprised of securities that are collateralized by residential and commercial mortgage loans valued based on models or matrices using multiple observable inputs, such as benchmark yields, reported trades and broker/dealer quotes, for identical or similar assets in active markets. The Company had holdings of $24.4 million and $30.0 million at September 30, 2017 and December 31, 2016 , respectively, in commercial mortgage-backed securities. Corporate securities/Short-term bonds : Valued based on a multi-dimensional model using multiple observable inputs, such as benchmark yields, reported trades, broker/dealer quotes and issue spreads, for identical or similar assets in active markets. Non-redeemable preferred stock : Valued based on observable inputs, such as underlying and common stock of same issuer and appropriate spread over a comparable U.S. Treasury security, for identical or similar assets in active markets. Total return swaps : Valued based on multi-dimensional models using inputs such as interest rate yield curves, underlying debt/credit instruments and the appropriate benchmark spread for similar assets in active markets, observable for substantially the full term of the contract. Collateralized loan obligations ("CLOs") : Valued based on underlying debt instruments and the appropriate benchmark spread for similar assets in active markets. Other asset-backed securities : Comprised of securities that are collateralized by non-mortgage assets, such as automobile loans, valued based on models or matrices using multiple observable inputs, such as benchmark yields, reported trades and broker/dealer quotes, for identical or similar assets in active markets. Note receivable : Valued based on observable inputs, such as benchmark yields, and considering any premium or discount for the differential between the stated interest rate and market interest rates, based on quoted market prices of similar instruments. Level 3 measurements - Fair values of financial assets are based on inputs that are both unobservable and significant to the overall fair value measurement, including any items in which the evaluated prices obtained elsewhere were deemed to be of a distressed trading level. Private equity funds : Private equity funds, excluding a private equity fund measured at net asset value ("NAV"), are valued based on underlying debt/credit instruments and the appropriate benchmark spread for similar assets in active markets taking into consideration unobservable inputs related to liquidity assumptions. Fair value measurement using NAV practical expedient - The fair value of the Company's investment in private equity fund measured at net asset value is determined using NAV as advised by the external fund manager and the third party administrator. The NAV of the Company's limited partnership interest in this fund is based on the manager's and the administrator's valuation of the underlying holdings in accordance with the fund's governing documents and GAAP. In accordance with applicable accounting guidance, this investment, measured at fair value using the NAV practical expedient, is not classified in the fair value hierarchy. The strategy of the fund is to provide current income to investors by investing mainly in equity tranches and sub-investment grade rated debt tranches of CLO issuers in the new and secondary markets, and equity interests in vehicles established to purchase and warehouse loans in anticipation of a CLO closing or to satisfy regulatory risk retention requirements associated with certain CLOs. The Company has made all of its capital contributions in the fund during the third quarter of 2017 and had no outstanding unfunded commitments at September 30, 2017 with respect to this fund. The underlying assets of the fund are expected to be liquidated over the period of one to five years from the final closing of the fund, which is expected to occur during the fourth quarter of 2017. The Company does not have the contractual option to redeem but will receive distributions based on the liquidation of the underlying assets and the interest proceeds from the underlying assets. In addition, the Company does not have the ability to withdraw from the fund, or to sell, assign, pledge or transfer its investment, without the consent from the general partner of the fund. The Company’s financial instruments at fair value are reflected in the consolidated balance sheets on a trade-date basis. Related unrealized gains or losses are recognized in net realized investment gains or losses in the consolidated statements of operations. Fair value measurements are not adjusted for transaction costs. The following tables present information about the Company’s assets and liabilities measured at fair value on a recurring basis, and indicate the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair values: September 30, 2017 Level 1 Level 2 Level 3 Total (Amounts in thousands) Assets Fixed maturity securities: U.S. government bonds and agencies $ 13,892 $ — $ — $ 13,892 Municipal securities — 2,483,750 — 2,483,750 Mortgage-backed securities — 32,726 — 32,726 Corporate securities — 161,883 — 161,883 Collateralized loan obligations — 94,325 — 94,325 Other asset-backed securities — 55,160 — 55,160 Total fixed maturity securities 13,892 2,827,844 — 2,841,736 Equity securities: Common stock 410,834 — — 410,834 Non-redeemable preferred stock — 30,665 — 30,665 Private equity funds — — 8,684 8,684 Private equity fund measured at net asset value (1) 69,011 Total equity securities 410,834 30,665 8,684 519,194 Short-term investments: Short-term bonds 29,996 18,893 — 48,889 Money market instruments 317,513 — — 317,513 Total short-term investments 347,509 18,893 — 366,402 Other assets: Note receivable — 5,585 — 5,585 Total assets at fair value $ 772,235 $ 2,882,987 $ 8,684 $ 3,732,917 Liabilities Other liabilities: Total return swaps $ — $ 1,589 $ — $ 1,589 Options sold 146 — — 146 Total liabilities at fair value $ 146 $ 1,589 $ — $ 1,735 __________ (1) The fair value is measured using the NAV practical expedient; therefore, it is not categorized within the fair value hierarchy. The fair value amount is presented in this table to permit reconciliation of the fair value hierarchy to the amounts presented in the Company's consolidated balance sheets. December 31, 2016 Level 1 Level 2 Level 3 Total (Amounts in thousands) Assets Fixed maturity securities: U.S. government bonds and agencies $ 12,275 $ — $ — $ 12,275 Municipal securities — 2,449,292 — 2,449,292 Mortgage-backed securities — 39,777 — 39,777 Corporate securities — 189,688 — 189,688 Collateralized loan obligations — 86,525 — 86,525 Other asset-backed securities — 36,996 — 36,996 Total fixed maturity securities 12,275 2,802,278 — 2,814,553 Equity securities: Common stock 316,450 — — 316,450 Non-redeemable preferred stock — 31,809 — 31,809 Private equity funds — — 9,068 9,068 Total equity securities 316,450 31,809 9,068 357,327 Short-term investments: Short-term bonds 70,393 20,233 — 90,626 Money market instruments 285,054 — — 285,054 Total short-term investments 355,447 20,233 — 375,680 Other assets: Total return swaps — 667 — 667 Total assets at fair value $ 684,172 $ 2,854,987 $ 9,068 $ 3,548,227 Liabilities Other liabilities: Total return swaps $ — $ 765 $ — $ 765 Options sold 20 — — 20 Total liabilities at fair value $ 20 $ 765 $ — $ 785 The following table presents a summary of changes in fair value of Level 3 financial assets and financial liabilities: Private Equity Funds Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (Amounts in thousands) Beginning balance $ 8,764 $ 8,972 $ 9,068 $ 10,431 Realized (losses) gains included in earnings (80 ) 564 (384 ) (895 ) Ending balance $ 8,684 $ 9,536 $ 8,684 $ 9,536 The amount of total (losses) gains for the period included in earnings attributable to assets still held at September 30 $ (80 ) $ 564 $ (384 ) $ (895 ) There were no transfers between Levels 1, 2, and 3 of the fair value hierarchy during the nine months ended September 30, 2017 and 2016 . At September 30, 2017 , the Company did not have any nonrecurring fair value measurements of nonfinancial assets or nonfinancial liabilities. Financial Instruments Disclosed, But Not Carried, at Fair Value The following tables present the carrying value and fair value of the Company’s financial instruments disclosed, but not carried, at fair value, and the level within the fair value hierarchy at which such instruments are categorized: September 30, 2017 Carrying Value Fair Value Level 1 Level 2 Level 3 (Amounts in thousands) Liabilities Notes payable: Unsecured notes $ 371,236 $ 385,733 $ — $ 385,733 $ — December 31, 2016 Carrying Value Fair Value Level 1 Level 2 Level 3 (Amounts in thousands) Liabilities Notes payable: Secured notes $ 140,000 $ 140,000 $ — $ 140,000 $ — Unsecured notes 180,000 180,000 — 180,000 — Secured Notes The fair values of the Company’s $120 million secured note and $20 million secured note at December 31, 2016 were estimated based on assumptions and inputs, such as the market value of underlying collateral and reset rates, for similarly termed notes that are observable in the market. In addition, the fair values of these secured notes approximate their carrying values, as the interest rates on these securities are variable and approximate current market interest rates. Unsecured Notes The fair value of the Company’s publicly traded $375 million unsecured note at September 30, 2017 was based on the spreads above the risk-free yield curve. These spreads are generally obtained from the new issue market, secondary trading and broker-dealer quotes. The fair value of the Company's $180 million unsecured note at December 31, 2016 was based on the unadjusted quoted price for similar notes in active markets. In addition, the fair value of this unsecured note approximates its carrying value, as the interest rate on this security is variable and approximates current market interest rates. See Note 11. Notes Payable for additional information on secured and unsecured notes.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2017
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Company is exposed to certain risks relating to its ongoing business operations. The primary risk managed by using derivative instruments is equity price risk. Equity contracts (options sold) on various equity securities are intended to manage the price risk associated with forecasted purchases or sales of such securities. The Company also enters into derivative contracts to enhance returns on its investment portfolio. On February 13, 2014 , Fannette Funding LLC (“FFL”), a special purpose investment vehicle formed and consolidated by the Company, entered into a total return swap agreement with Citibank. Under the agreement, FFL receives the income equivalent on underlying obligations due to Citibank and pays to Citibank interest on the outstanding notional amount of the underlying obligations. The total return swap is secured by approximately $30 million of U.S. Treasuries as collateral, which are included in short-term investments on the consolidated balance sheets. The Company paid interest, which was equal to LIBOR plus 145 basis points prior to the renewal of the agreement in January 2017 and LIBOR plus 128 basis points subsequent to the renewal, on approximately $98 million and $108 million of underlying obligations as of September 30, 2017 and December 31, 2016 , respectively. The agreement had an initial term of one year, subject to annual renewal. In January 2017, the agreement was renewed for an additional year expiring February 17, 2018, and the interest rate was changed to LIBOR plus 128 basis points. On August 9, 2013 , Animas Funding LLC (“AFL”), a special purpose investment vehicle formed and consolidated by the Company, entered into a three -year total return swap agreement with Citibank, which has been renewed for an additional one-year term through February 17, 2018. The total portfolio of underlying obligations was liquidated during June 2017, and the total return swap agreement between AFL and Citibank was terminated on July 7, 2017. Under the agreement, AFL received the income equivalent on underlying obligations due to Citibank and paid to Citibank interest on the outstanding notional amount of the underlying obligations. The total return swap was secured by approximately $40 million of U.S. Treasuries as collateral, which were included in short-term investments on the consolidated balance sheets. The Company paid interest, which was equal to LIBOR plus 135 basis points prior to the amendment of the agreement in January 2017 and LIBOR plus 128 basis points subsequent to the amendment, on approximately $152 million of underlying obligations as of December 31, 2016 . The following tables present the location and amounts of derivative fair values in the consolidated balance sheets and derivative gains or losses in the consolidated statements of operations: Asset Derivatives Liability Derivatives September 30, 2017 December 31, 2016 September 30, 2017 December 31, 2016 (Amounts in thousands) Total return swaps - Other assets $ — $ 667 $ — $ — Options sold - Other liabilities — — 146 20 Total return swaps - Other liabilities — — 1,589 765 Total derivatives $ — $ 667 $ 1,735 $ 785 Gains (Losses) Recognized in Income Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (Amounts in thousands) Total return swaps - Net realized investment gains (losses) $ 118 $ 4,172 $ (2,535 ) $ 7,915 Options sold - Net realized investment gains 557 1,030 1,857 3,324 Total $ 675 $ 5,202 $ (678 ) $ 11,239 Most options sold consist of covered calls. The Company writes covered calls on underlying equity positions held as an enhanced income strategy that is permitted for the Company’s insurance subsidiaries under statutory regulations. The Company manages the risk associated with covered calls through strict capital limitations and asset diversification throughout various industries. See Note 5. Fair Value Measurements for additional disclosures regarding options sold.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill There were no changes in the carrying amount of goodwill during the three and nine months ended September 30, 2017 and 2016 . Goodwill is reviewed annually for impairment and more frequently if potential impairment indicators exist. No impairment indicators were identified during the three and nine months ended September 30, 2017 and 2016 . All of the Company's goodwill is associated with the Property and Casualty business segment (See Note 13. Segment Information for additional information on the reportable business segment). Other Intangible Assets The following table presents the components of other intangible assets: Gross Carrying Amount Accumulated Amortization Net Carrying Amount Useful Lives (Amounts in thousands) (in years) As of September 30, 2017: Customer relationships $ 52,430 $ (42,542 ) $ 9,888 11 Trade names 15,400 (5,615 ) 9,785 24 Technology 4,300 (3,762 ) 538 10 Insurance license 1,400 — 1,400 Indefinite Total other intangible assets, net $ 73,530 $ (51,919 ) $ 21,611 As of December 31, 2016: Customer relationships $ 52,430 $ (39,332 ) $ 13,098 11 Trade names 15,400 (5,133 ) 10,267 24 Technology 4,300 (3,440 ) 860 10 Insurance license 1,400 — 1,400 Indefinite Total other intangible assets, net $ 73,530 $ (47,905 ) $ 25,625 Other intangible assets are reviewed annually for impairment and more frequently if potential impairment indicators exist. No impairment indicators were identified during the three and nine months ended September 30, 2017 and 2016 . Other intangible assets with definite useful lives are amortized on a straight-line basis over their useful lives. Other intangible assets amortization expense was $1.3 million and $1.5 million for the three months ended September 30, 2017 and 2016 , respectively, and $4.0 million and $4.6 million for the nine months ended September 30, 2017 and 2016 , respectively. The following table presents the estimated future amortization expense related to other intangible assets as of September 30, 2017 : Year Amortization Expense (Amounts in thousands) Remainder of 2017 $ 1,335 2018 5,335 2019 4,905 2020 758 2021 738 Thereafter 7,140 Total $ 20,211

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 2017
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Share-Based Compensation	Share-Based Compensation Share-based compensation expense for all stock options granted or modified is based on the estimated grant-date fair value. The Company recognizes these compensation costs on a straight-line basis over the requisite service period of the award. As of September 30, 2017 , all outstanding stock options have a term of ten years from the date of grant and become exercisable in four equal installments on the first through fourth anniversaries of the grant date. The fair value of stock option awards is estimated using the Black-Scholes option pricing model with the grant-date assumptions and weighted-average fair values. In February 2015, the Company's Board of Directors adopted the 2015 Incentive Award Plan (the "2015 Plan"), replacing the 2005 Equity Incentive Plan (the "2005 Plan") which expired in January 2015. The 2015 Plan was approved at the Company's Annual Meeting of Shareholders in May 2015. A maximum of 4,900,000 shares of common stock are authorized for issuance under the 2015 Plan upon exercise of stock options, stock appreciation rights and other awards, or upon vesting of restricted stock unit ("RSU") or deferred stock awards. As of September 30, 2017 , 172,000 RSUs were outstanding and 4,728,000 shares of common stock were available for future issuances under the 2015 Plan. The Compensation Committee of the Company’s Board of Directors granted RSU awards to the Company’s senior management and key employees which will vest based upon the Company's performance during three-year performance periods ending on December 31, 2017 and 2018: Grant Year 2016 2015 Three-year performance period ending December 31, 2018 2017 Vesting shares, target (net of forfeited) 84,750 87,250 Vesting shares, maximum (net of forfeited) 158,906 163,594 The RSUs vest at the end of a three -year performance period beginning with the year of the grant, and then only if, and to the extent that, the Company’s performance during the performance period achieves the threshold established by the Compensation Committee of the Company’s Board of Directors. Performance thresholds are based on the Company’s cumulative underwriting income, annual underwriting income, and net earned premium growth. In March 2017, a total of approximately $3.6 million was paid upon the vesting of 61,445 RSUs awarded in 2014 resulting from the attainment of performance goals above the target threshold during the three -year performance period ended December 31, 2016 . In February 2016, 88,074 shares of common stock, net of 58,822 shares withheld for payroll taxes, were issued upon the vesting of 146,896 RSUs awarded in 2013 resulting from the attainment of performance goals above the target threshold during the three -year performance period ended December 31, 2015. As of September 30, 2017 , 11,000 and 12,000 target RSUs granted in 2016 and 2015, respectively, were forfeited because the recipients were no longer employed by the Company. The fair value of each RSU grant was determined based on the market price of the Company's common stock on the grant date for awards classified as equity and on each reporting date for awards classified as liability. Compensation cost is recognized based on management’s best estimate of the performance goals that will be achieved. If the minimum performance goals are not met, no compensation cost will be recognized and any recognized compensation cost will be reversed. No stock options or RSUs were awarded during the nine months ended September 30, 2017 .

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2017
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Income Taxes	Income Taxes For financial statement purposes, the Company recognizes tax benefits related to positions taken, or expected to be taken, on a tax return only if, the positions are “more-likely-than-not” sustainable. Once this threshold has been met, the Company’s measurement of its expected tax benefits is recognized in its consolidated financial statements. There was a $38,000 increase to the total amount of unrecognized tax benefits related to tax uncertainties during the nine months ended September 30, 2017 . The increase was the result of tax positions taken regarding federal tax credits and state tax apportionment issues based on management’s best judgment given the facts, circumstances, and information available at the reporting date. The Company does not expect any changes in such unrecognized tax benefits to have a significant impact on its consolidated financial statements within the next 12 months. The Company and its subsidiaries file income tax returns with the Internal Revenue Service and the taxing authorities of various states. Tax years that remain subject to examination by major taxing jurisdictions are 2014 through 2016 for federal taxes, and 2003 through 2016 for California state taxes. The Company is currently under examination by the California Franchise Tax Board (“FTB”) for tax years 2003 through 2013. The FTB issued Notices of Proposed Assessments ("NPAs") to the Company for tax years 2003 through 2010, which the Company formally protested. The proposed adjustments for tax years 2003 through 2006 were affirmed following an administrative protest process with the FTB examination. The Company is in settlement discussions with the FTB and believes a reasonable settlement could be reached during 2017 or early 2018 with regard to tax years 2003 through 2010. If a reasonable settlement is not reached, the Company intends to pursue other options, including a formal hearing with the State Board of Equalization, an appeal with the California Office of Tax Appeals, or litigation in superior court. The FTB has not yet issued NPAs for the 2011 through 2013 tax years. Management believes that the resolution of these examinations and assessments will not have a material impact on the Company's consolidated financial statements. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial reporting basis and the respective tax basis of the Company’s assets and liabilities, and expected benefits of utilizing net operating loss, capital loss, and tax-credit carryforwards. The Company assesses the likelihood that its deferred tax assets will be realized and, to the extent management does not believe these assets are more likely than not to be realized, a valuation allowance is established. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates or laws is recognized in earnings in the period that includes the enactment date. At September 30, 2017 , the Company’s deferred income taxes were in a net asset position, which included a combination of ordinary and capital deferred tax benefits. In assessing the Company’s ability to realize deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon generating sufficient taxable income of the appropriate character within the carryback and carryforward periods available under the tax law. Management considers the reversal of deferred tax liabilities, projected future taxable income of an appropriate nature, and tax-planning strategies in making this assessment. The Company believes that through the use of prudent tax planning strategies and the generation of capital gains, sufficient income will be realized in order to maximize the full benefits of its deferred tax assets. Although realization is not assured, management believes that it is more likely than not that the Company’s deferred tax assets will be realized.

Losses And Loss Adjustment Expe

Losses And Loss Adjustment Expense Reserves	9 Months Ended
	Sep. 30, 2017
Insurance Loss Reserves [Abstract]
Losses And Loss Adjustment Expense Reserves	Loss and Loss Adjustment Expense Reserves The following table presents the activity in loss and loss adjustment expense reserves: Nine Months Ended September 30, 2017 2016 (Amounts in thousands) Gross reserves at January 1 $ 1,290,248 $ 1,146,688 Less reinsurance recoverable (13,161 ) (14,253 ) Net reserves at January 1 1,277,087 1,132,435 Incurred losses and loss adjustment expenses related to: Current year 1,772,203 1,696,350 Prior years 18,347 69,134 Total incurred losses and loss adjustment expenses 1,790,550 1,765,484 Loss and loss adjustment expense payments related to: Current year 1,099,656 1,065,948 Prior years 606,615 601,379 Total payments 1,706,271 1,667,327 Net reserves at September 30 1,361,366 1,230,592 Reinsurance recoverable 10,798 13,961 Gross reserves at September 30 $ 1,372,164 $ 1,244,553 The increase in the provision for insured events of prior years in 2017 of approximately $18.3 million was primarily attributable to higher than estimated California automobile and property losses. The increase in the provision for insured events of prior years in 2016 of approximately $69.1 million primarily resulted from the re-estimation of losses for California and Florida automobile liability coverages. For the nine months ended September 30, 2017 and 2016 , the Company recorded catastrophe losses of approximately $59 million and $23 million , respectively. The 2017 catastrophe losses were primarily due to severe rainstorms in California, the impact of Hurricane Harvey in Texas and Hurricane Irma in Florida and Georgia, and storms and tornadoes in Oklahoma and Texas. The Winter of 2017 was extremely wet in California, setting new precipitation records in parts of the state. The 2016 catastrophe losses were primarily attributable to severe storms in Texas and Northern California and claims from the Sand Fire in Southern California.

Notes Payable

Notes Payable	9 Months Ended
	Sep. 30, 2017
Notes Payable [Abstract]
Notes Payable	Notes Payable The following table presents information about the Company's notes payable: Lender Interest Rate Maturity Date September 30, 2017 December 31, 2016 (Amounts in thousands) Secured credit facility (1) Bank of America LIBOR plus 40 basis points December 3, 2018 $ — $ 120,000 Secured loan (1) Union Bank LIBOR plus 40 basis points December 3, 2017 — 20,000 Unsecured credit facility (1) Bank of America and Union Bank LIBOR plus 112.5-162.5 basis points December 3, 2019 — 180,000 Senior unsecured notes (2) Publicly traded 4.40% March 15, 2027 375,000 — Unsecured credit facility (3) Bank of America and Wells Fargo Bank LIBOR plus 112.5-162.5 basis points March 29, 2022 — — Total principal amount 375,000 320,000 Less unamortized discount and debt issuance costs (4) 3,764 — Total debt $ 371,236 $ 320,000 __________ (1) On March 8, 2017, the loan and credit facility agreements were terminated and the Company repaid the total outstanding amounts with the proceeds from its public offering of $375 million of senior notes. (2) On March 8, 2017, the Company completed a public debt offering issuing $375 million of senior notes. The notes are unsecured senior obligations of the Company, with a 4.40% annual coupon payable on March 15 and September 15 of each year commencing September 15, 2017. These notes mature on March 15, 2027. The Company used the proceeds from the notes to pay off amounts outstanding under the existing loan and credit facilities and for general corporate purposes. The Company incurred debt issuance costs of approximately $3.4 million , inclusive of underwriters' fees. The notes were issued at a slight discount of 99.847% of par, resulting in the effective annualized interest rate, including debt issuance costs, of approximately 4.45% . (3) On March 29, 2017, the Company entered into an unsecured credit agreement that provides for revolving loans of up to $50 million and matures on March 29, 2022. The interest rates on borrowings under the credit facility are based on the Company's debt to total capital ratio and range from LIBOR plus 112.5 basis points when the ratio is under 15% to LIBOR plus 162.5 basis points when the ratio is greater than or equal to 25%. Commitment fees for the undrawn portions of the credit facility range from 12.5 basis points when the ratio is under 15% to 22.5 basis points when the ratio is greater than or equal to 25%. The debt to total capital ratio is expressed as a percentage of (a) consolidated debt to (b) consolidated shareholders' equity plus consolidated debt. The Company's debt to total capital ratio was 17.4% at September 30, 2017 , resulting in a 15 basis point commitment fee on the $50 million undrawn portion of the credit facility. As of October 26, 2017 , there have been no borrowings under this facility. (4) The unamortized discount and debt issuance costs of approximately $3.8 million are associated with the publicly traded $375 million senior unsecured notes. These are amortized to interest expense over the life of the notes, and the unamortized balance is presented in the Company's consolidated balance sheets as a direct deduction from the carrying amount of the debt. The unamortized debt issuance cost of approximately $0.2 million associated with the $50 million five -year unsecured revolving credit facility maturing on March 29, 2022 is included in other assets in the Company's consolidated balance sheets and amortized to interest expense over the term of the credit facility.

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies The Company is, from time to time, named as a defendant in various lawsuits or regulatory actions incidental to its insurance business. The majority of lawsuits brought against the Company relate to insurance claims that arise in the normal course of business and are reserved for through the reserving process. For a discussion of the Company’s reserving methods, see the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 . In March 2006, the California DOI issued an Amended Notice of Non-Compliance to a Notice of Non-Compliance originally issued in February 2004 (as amended, “2004 NNC”) alleging that the Company charged rates in violation of the California Insurance Code, willfully permitted its agents to charge broker fees in violation of California law, and willfully misrepresented the actual price insurance consumers could expect to pay for insurance by the amount of a fee charged by the consumer's insurance broker. The California DOI sought to impose a fine for each policy on which the Company allegedly permitted an agent to charge a broker fee, to impose a penalty for each policy on which the Company allegedly used a misleading advertisement, and to suspend certificates of authority for a period of one year. In January 2012, the administrative law judge bifurcated the 2004 NNC between (a) the California DOI’s order to show cause (the “OSC”), in which the California DOI asserts the false advertising allegations and accusation, and (b) the California DOI’s notice of noncompliance (the “NNC”), in which the California DOI asserts the unlawful rate allegations. In February 2012, the administrative law judge (“ALJ”) submitted a proposed decision dismissing the NNC, but the Commissioner rejected the ALJ’s proposed decision. The Company challenged the rejection in Los Angeles Superior Court in April 2012, and the Commissioner responded with a demurrer. Following a hearing, the Superior Court sustained the Commissioner’s demurrer, based on the Company’s failure to exhaust its administrative remedies, and the Company appealed. The Court of Appeal affirmed the Superior Court's ruling that the Company was required to exhaust its administrative remedies, but expressly preserved for later appeal the legal basis for the ALJ’s dismissal: violation of the Company’s due process rights. Following an evidentiary hearing in April 2013, post-hearing briefs, and an unsuccessful mediation, the ALJ closed the evidentiary record on April 30, 2014. Although a proposed decision was to be submitted to the Commissioner on or before June 30, 2014, after which the Commissioner would have 100 days to accept, reject or modify the proposed decision, the proposed decision was not submitted until December 8, 2014. On January 7, 2015, the Commissioner adopted the ALJ’s proposed decision, which became the Commissioner’s adopted order (the "Order"). The decision and Order found that from the period July 1, 1996, through 2006, the Company’s "brokers" were actually operating as "de facto agents" and that the charging of "broker fees" by these producers constituted the charging of "premium" in excess of the Company's approved rates, and assessed a civil penalty in the amount of $27.6 million against the Company. On February 9, 2015, the Company filed a Writ of Administrative Mandamus and Complaint for Declaratory Relief (the “Writ”) in the Orange County Superior Court seeking, among other things, to require the Commissioner to vacate the Order, to stay the Order while the Superior Court action is pending, and to judicially declare as invalid the Commissioner’s interpretation of certain provisions of the California Insurance Code. Subsequent to the filing of the Writ, a consumer group petitioned and was granted the right to intervene in the Superior Court action. The Court did not order a stay, and the $27.6 million assessed penalty was paid in March 2015. The Company filed an amended Writ on September 11, 2015, adding an explicit request for a refund of the penalty, with interest. On August 12, 2016, the Superior Court issued its ruling on the Writ, for the most part granting the relief sought by the Company. The Superior Court found that the Commissioner and the California DOI did commit due process violations, but declined to dismiss the case on those grounds. The Superior Court also agreed with the Company that the broker fees at issue were not premium, and that the penalties imposed by the Commissioner were improper, and therefore vacated the Order imposing the penalty. The Superior Court entered final judgment on November 17, 2016, issuing a writ requiring the Commissioner to refund the entire penalty amount within 120 days, plus prejudgment interest at the statutory rate of 7% . On January 12, 2017, the California DOI filed a notice of appeal of the Superior Court's judgment entered on November 17, 2016. While the appeal is still pending, the California DOI returned the entire penalty amount plus accrued interest, a total of $30.9 million , to the Company in June 2017 in order to avoid accruing further interest. Because the matter has been appealed, the Company has not yet recognized the $30.9 million as a gain in the consolidated statements of operations; instead, the Company recorded the $30.9 million plus interest earned, a total of approximately $31.0 million at September 30, 2017, in other liabilities in the consolidated balance sheets. The Company had filed a motion to dismiss the false advertising portion of the case based on the Superior Court's findings, but the ALJ denied that motion after the appeal was filed. The ALJ did, however, grant the Company's alternative request to stay further proceedings pending the final determination of the appeal. The Company has accrued a liability for the estimated cost to continue to defend itself in the false advertising OSC. Based upon its understanding of the facts and the California Insurance Code, the Company does not expect that the ultimate resolution of the false advertising OSC will be material to its financial position. The Company establishes reserves for non-insurance claims related lawsuits, regulatory actions, and other contingencies when the Company believes a loss is probable and is able to estimate its potential exposure. For loss contingencies believed to be reasonably possible, the Company also discloses the nature of the loss contingency and an estimate of the possible loss, range of loss, or a statement that such an estimate cannot be made. While actual losses may differ from the amounts recorded and the ultimate outcome of the Company's pending actions is generally not yet determinable, the Company does not believe that the ultimate resolution of currently pending legal or regulatory proceedings, either individually or in the aggregate, will have a material adverse effect on its financial condition or cash flows. In all cases, the Company vigorously defends itself unless a reasonable settlement appears appropriate. For a discussion of legal matters, see the Company’s Annual Report on Form 10-K for the year ended December 31, 2016.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Segment Information	Segment Information The Company is primarily engaged in writing personal automobile insurance and provides related property and casualty insurance products to its customers through 14 subsidiaries in 11 states, principally in California. The Company has one reportable business segment - the Property and Casualty business segment. The Company’s Chief Operating Decision Maker evaluates operating results based on pre-tax underwriting results which is calculated as net premiums earned less (a) losses and loss adjustment expenses and (b) underwriting expenses (policy acquisition costs and other operating expenses). Expenses are allocated based on certain assumptions that are primarily related to premiums and losses. The Company’s net investment income, net realized investment gains or losses, other income, and interest expense are excluded in evaluating pretax underwriting profit. The Company does not allocate its assets, including investments, or income taxes in evaluating pre-tax underwriting profit. Property and Casualty Lines The Property and Casualty business segment offers several insurance products to the Company’s individual customers and small business customers. These insurance products are: private passenger automobile which is the Company’s primary business, and related insurance products such as homeowners, commercial automobile and commercial property. These related insurance products are primarily sold to the Company’s individual customers and small business customers, which increases retention of the Company’s private passenger automobile client base. The insurance products comprising the Property and Casualty business segment are sold through the same distribution channels, mainly through independent and 100% owned insurance agents, and go through a similar underwriting process. Other Lines The Other business segment represents net premiums written and earned from an operating segment that does not meet the quantitative thresholds required to be considered a reportable segment. This operating segment offers automobile mechanical protection warranties which are primarily sold through automobile dealerships and credit unions. The following tables present the Company's operating results by reportable segment: Three Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Net premiums earned $ 792.7 $ 8.5 $ 801.2 $ 780.6 $ 10.3 $ 790.9 Less: Losses and loss adjustment expenses 591.1 4.2 595.3 570.8 5.5 576.3 Underwriting expenses 196.7 3.9 200.6 194.8 4.5 199.3 Underwriting gain 4.9 0.4 5.3 15.0 0.3 15.3 Investment income 31.0 30.3 Net realized investment gains (losses) 20.7 (15.5 ) Other income 5.4 2.4 Interest expense (4.2 ) (0.9 ) Pre-tax income $ 58.2 $ 31.6 Net income $ 46.5 $ 26.9 Nine Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Net premiums earned $ 2,362.4 $ 26.2 $ 2,388.6 $ 2,305.0 $ 32.3 $ 2,337.3 Less: Losses and loss adjustment expenses 1,777.1 13.5 1,790.6 1,748.2 17.3 1,765.5 Underwriting expenses 587.7 11.9 599.6 586.1 13.6 599.7 Underwriting (loss) gain (2.4 ) 0.8 (1.6 ) (29.3 ) 1.4 (27.9 ) Investment income 94.1 91.4 Net realized investment gains 66.3 55.0 Other income 9.7 6.4 Interest expense (10.9 ) (2.9 ) Pre-tax income $ 157.6 $ 122.0 Net income $ 125.1 $ 99.1 The following tables present the Company’s net premiums earned and direct premiums written by line of insurance business: Three Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Private passenger automobile $ 619.8 $ — $ 619.8 $ 614.0 $ — $ 614.0 Homeowners 108.3 — 108.3 105.5 — 105.5 Commercial automobile 43.6 — 43.6 41.2 — 41.2 Other 21.0 8.5 29.5 19.9 10.3 30.2 Net premiums earned $ 792.7 $ 8.5 $ 801.2 $ 780.6 $ 10.3 $ 790.9 Private passenger automobile $ 633.7 $ — $ 633.7 $ 630.1 $ — $ 630.1 Homeowners 125.8 — 125.8 116.0 — 116.0 Commercial automobile 45.6 — 45.6 41.9 — 41.9 Other 22.9 7.1 30.0 22.4 6.6 29.0 Direct premiums written $ 828.0 $ 7.1 $ 835.1 $ 810.4 $ 6.6 $ 817.0 Nine Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Private passenger automobile $ 1,850.3 $ — $ 1,850.3 $ 1,820.1 $ — $ 1,820.1 Homeowners 322.3 — 322.3 307.0 — 307.0 Commercial automobile 127.3 — 127.3 119.8 — 119.8 Other 62.5 26.2 88.7 58.1 32.3 90.4 Net premiums earned $ 2,362.4 $ 26.2 $ 2,388.6 $ 2,305.0 $ 32.3 $ 2,337.3 Private passenger automobile $ 1,872.8 $ — $ 1,872.8 $ 1,857.3 $ — $ 1,857.3 Homeowners 352.3 — 352.3 331.4 — 331.4 Commercial automobile 133.7 — 133.7 125.2 — 125.2 Other 69.9 21.3 91.2 66.3 20.9 87.2 Direct premiums written $ 2,428.7 $ 21.3 $ 2,450.0 $ 2,380.2 $ 20.9 $ 2,401.1

Subsequent Event

Subsequent Event	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event In October 2017 , a series of destructive wildfires burned across several counties in Northern California. Recent estimates put the total number of structures destroyed at over 8,000 . Based on claims reported to date and expected to be reported, the Company estimates that its share of the total structures destroyed will be fewer than 100 . The Company estimates a total gross loss in the range of $60 million to $100 million and a net loss, after the benefit of reinsurance, of $10 million , plus any reinstatement premiums required under the terms of the Company's catastrophe reinsurance treaty. Due to the recent occurrence and magnitude of this event, the total losses from these wildfires are difficult to estimate, and these figures may change in the future. The Company benefited significantly from its newly expanded catastrophe reinsurance treaty that became effective July 1, 2017 . Under the reinsurance treaty, covered catastrophe losses are reinsured 100% up to $190 million above the Company's $10 million retention. Losses above $200 million are shared pro-rata with 5% coverage by the reinsurers and 95% retention by the Company, up to a total of $15 million in coverage provided by the reinsurers. The reinsurance treaty is subject to reinstatement premiums based on the amount of reinsurance benefits paid to the Company, up to the maximum reinstatement premium of $19 million if the full amount of benefit is used.

General (Policy)

General (Policy)	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation and Basis of Presentation	The interim consolidated financial statements include the accounts of Mercury General Corporation and its subsidiaries (referred to herein collectively as the “Company”). For the list of the Company’s subsidiaries, see Note 1. Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 . These interim financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”), which differ in some respects from those filed in reports to insurance regulatory authorities. The financial data of the Company included herein are unaudited. In the opinion of management, all material adjustments of a normal recurring nature have been made to present fairly the Company’s financial position at September 30, 2017 and the results of operations and cash flows for the periods presented. All intercompany transactions and balances have been eliminated. Certain financial information that is normally included in annual financial statements prepared in accordance with GAAP, but that is not required for interim reporting purposes, has been omitted from the accompanying interim consolidated financial statements and related notes. Readers are urged to review the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 for more complete descriptions and discussions. Operating results and cash flows for the nine months ended September 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 .
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates require the Company to apply complex assumptions and judgments, and often the Company must make estimates about the effects of matters that are inherently uncertain and will likely change in subsequent periods. The most significant assumptions in the preparation of these consolidated financial statements relate to reserves for losses and loss adjustment expenses. Actual results could differ from those estimates. See Note 1. Summary of Significant Accounting Policies of the Notes to Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016
Earnings per Share	Potentially dilutive securities representing approximately 22,000 and 29,000 shares of common stock for the three and nine months ended September 30, 2016 , respectively, were excluded from the computation of diluted earnings per common share because their effect would have been anti-dilutive.
Deferred Policy Acquisition Costs	Deferred policy acquisition costs consist of commissions paid to outside agents, premium taxes, salaries, and certain other underwriting costs that are incremental or directly related to the successful acquisition of new and renewal insurance contracts and are amortized over the life of the related policy in proportion to premiums earned. Deferred policy acquisition costs are limited to the amount that will remain after deducting from unearned premiums and anticipated investment income, the estimated losses and loss adjustment expenses, and the servicing costs that will be incurred as premiums are earned. The Company’s deferred policy acquisition costs are further limited by excluding those costs not directly related to the successful acquisition of insurance contracts. Deferred policy acquisition cost amortization was $136.3 million and $140.2 million for the three months ended September 30, 2017 and 2016 , respectively, and $416.7 million and $421.7 million for the nine months ended September 30, 2017 and 2016 , respectively. The Company does not defer advertising expenditures but expenses them as incurred. The Company recorded net advertising expense of approximately $32.0 million and $34.1 million for the nine months ended September 30, 2017 and 2016 , respectively.
Recently Issued Accounting Standards	In May 2017, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2017-09, " Compensation - Stock Compensation (Topic 718), Scope of Modification Accounting. " ASU 2017-09 provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting in Topic 718. ASU 2017-09 will be effective for the Company beginning January 1, 2018 with early adoption permitted. The Company does not anticipate that ASU 2017-09 will have a material impact on its consolidated financial statements and related disclosures. In January 2017, the FASB issued ASU 2017-04, " Intangibles - Goodwill and Other (Topic 350), Simplifying the Test for Goodwill Impairment. " ASU 2017-04 removes the requirement to compare the implied fair value of goodwill with its carrying amount as part of Step 2 of the goodwill impairment test and requires an entity to recognize an impairment charge for the amount by which the carrying amount of a reporting unit exceeds its fair value. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. ASU 2017-04 will be effective for the Company beginning January 1, 2020 with early adoption permitted. The Company does not anticipate that ASU 2017-04 will have a material impact on its consolidated financial statements and related disclosures. In October 2016, the FASB issued ASU 2016-16, " Income Taxes (Topic 740), Intra-Entity Transfers of Assets Other Than Inventory. " ASU 2016-16 requires entities to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Current GAAP prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. ASU 2016-16 will be effective for the Company beginning January 1, 2018. The Company is evaluating the impact that ASU 2016-16 will have on its consolidated financial statements and related disclosures. In August 2016, the FASB issued ASU 2016-15, " Classification of Certain Cash Receipts and Cash Payments (Topic 230). " The new guidance is intended to reduce diversity in how certain transactions are classified in the consolidated statement of cash flows. ASU 2016-15 will be effective for the Company beginning January 1, 2018. The Company is evaluating the impact that ASU 2016-15 will have on its consolidated financial statements and related disclosures. In June 2016, the FASB issued ASU 2016-13, " Financial Instruments - Credit Losses (Topic 326). " The amendments in this ASU replace the "incurred loss" methodology for recognizing credit losses with a methodology that reflects expected credit losses and requires consideration of a broader range of information including past events, current conditions and reasonable and supportable forecasts that affect the collectibility of reported amounts of financial assets that are not accounted for at fair value through net income, such as loans, certain debt securities, trade receivables, net investment in leases, off-balance sheet credit exposures and reinsurance receivables. Under the current GAAP incurred loss methodology, recognition of the full amount of credit losses is generally delayed until the loss is probable of occurring. Current GAAP restricts the ability to record credit losses that are expected, but do not yet meet the probability threshold. ASU 2016-13 will be effective for the Company beginning with the first quarter ending March 31, 2020. While the Company is in the process of evaluating the impact of ASU 2016-13, it does not expect this ASU to have a material impact on its consolidated financial statements and related disclosures as most of its financial instruments with potential exposure to material credit losses are accounted for at fair value through net income. In March 2016, the FASB issued ASU 2016-09, " Compensation - Stock Compensation (Topic 718) ," which simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The Company adopted ASU 2016-09 for the quarter ended March 31, 2017. As a result of the adoption, the Company recognizes excess tax benefits in its provision for income taxes rather than paid-in capital. Additional amendments to accounting for income taxes and minimum statutory withholding tax requirements had no impact to retained earnings as of January 1, 2017, where the cumulative effect of these changes are required to be recorded. The Company elected to continue to estimate forfeitures expected to occur to determine the amount of compensation cost to be recognized in each period. The Company also elected to apply the presentation requirements for cash flows related to excess tax benefits retrospectively to all periods presented, which resulted in an increase to both net cash provided by operating activities and net cash used in financing activities of approximately $995,000 for the nine months ended September 30, 2016 . The adoption of the presentation requirements for cash flows related to employee taxes paid with shares resulted in an increase to both net cash provided by operating activities and net cash used in financing activities of approximately $3,270,000 for the nine months ended September 30, 2016 . In February 2016, the FASB issued ASU 2016-02, " Leases (Topic 842) ," which supersedes the guidance in Accounting Standards Codification ("ASC") 840, "Leases." ASU 2016-02 requires a lessee to recognize lease assets and lease liabilities resulting from all leases. ASU 2016-02 retains the distinction between a finance lease and an operating lease. Lessor accounting is largely unchanged from ASC 840. ASU 2016-02 will be effective for the Company beginning January 1, 2019. However, in transition, the Company will be required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. While the Company is in the process of evaluating the impact of ASU 2016-02, it does not expect this ASU to have a material impact on its consolidated financial statements, except for recognizing lease assets and lease liabilities for its operating leases. The Company's lease obligations under various non-cancellable operating lease agreements amounted to approximately $27,000,000 at December 31, 2016. In January 2016, the FASB issued ASU 2016-01, " Financial Instruments-Overall (Subtopic 825-10) , Recognition and Measurement of Financial Assets and Financial Liabilities. " The amendments in this ASU address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU 2016-01: (1) requires equity investments (except those accounted for under the equity method or those that result in the consolidation of the investee) to be measured at fair value with changes in the fair value recognized in net income; (2) simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; (3) eliminates the requirement for public business entities to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet; (4) requires the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (5) requires separate presentation of financial assets and financial liabilities by measurement category and form of financial asset on the balance sheet or the notes to the financial statements; and (6) clarifies that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity’s other deferred tax assets. ASU 2016-01 will be effective for the Company beginning January 1, 2018. The Company does not anticipate that ASU 2016-01 will have a material impact on its consolidated financial statements and related disclosures. In May 2014, the FASB issued ASU 2014-09, " Revenue from Contracts with Customers (Topic 606). " ASU 2014-09 requires entities to apply a five-step model to determine the amount and timing of revenue recognition. The model specifies, among other criteria, that revenue should be recognized when an entity transfers control of goods or services to a customer in the amount to which the entity expects to be entitled. In August 2015, the FASB issued ASU 2015-14, " Revenue from Contracts with Customers (Topic 606), Deferral of the Effective Date ," which deferred the effective date of ASU 2014-09 for the Company to January 1, 2018. Subsequently, the FASB has issued additional ASUs on Topic 606 that do not change the core principle of the guidance in ASU 2014-09 but merely clarify certain aspects of it. The additional ASUs will also be effective for the Company beginning January 1, 2018. Two methods of transition are permitted upon adoption: full retrospective and modified retrospective. The Company is evaluating both methods of transition and it is currently anticipated that a modified retrospective adoption approach will be used. However, as the accounting for insurance contracts is outside of the scope of ASU 2014-09, the Company does not expect the adoption of this ASU to have a material impact on its consolidated financial statements and related disclosures.

Financial Instruments (Tables)

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
Financial Instruments, Owned, at Fair Value [Abstract]
Estimated Fair Values of Financial Instruments	The following table presents the fair values of financial instruments: September 30, 2017 December 31, 2016 (Amounts in thousands) Assets Investments $ 3,727,332 $ 3,547,560 Note receivable 5,585 — Total return swaps — 667 Liabilities Total return swaps $ 1,589 $ 765 Options sold 146 20 Secured notes — 140,000 Unsecured notes 385,733 180,000

Fair Value Option (Tables)

Fair Value Option (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Option [Abstract]
Gains And Losses Due To Changes In Fair Value Of Investments	The following table presents gains (losses) due to changes in fair value of investments and note receivable that are measured at fair value pursuant to the application of the fair value option: Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (Amounts in thousands) Fixed maturity securities $ 9,796 $ (19,521 ) $ 45,705 $ 20,913 Equity securities 7,765 (2,143 ) 14,227 13,430 Short-term investments 150 532 (89 ) 184 Total investments 17,711 (21,132 ) 59,843 34,527 Note receivable (103 ) — (103 ) — Total gains (losses) $ 17,608 $ (21,132 ) $ 59,740 $ 34,527

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2017
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Valuation Techniques	The following tables present information about the Company’s assets and liabilities measured at fair value on a recurring basis, and indicate the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair values: September 30, 2017 Level 1 Level 2 Level 3 Total (Amounts in thousands) Assets Fixed maturity securities: U.S. government bonds and agencies $ 13,892 $ — $ — $ 13,892 Municipal securities — 2,483,750 — 2,483,750 Mortgage-backed securities — 32,726 — 32,726 Corporate securities — 161,883 — 161,883 Collateralized loan obligations — 94,325 — 94,325 Other asset-backed securities — 55,160 — 55,160 Total fixed maturity securities 13,892 2,827,844 — 2,841,736 Equity securities: Common stock 410,834 — — 410,834 Non-redeemable preferred stock — 30,665 — 30,665 Private equity funds — — 8,684 8,684 Private equity fund measured at net asset value (1) 69,011 Total equity securities 410,834 30,665 8,684 519,194 Short-term investments: Short-term bonds 29,996 18,893 — 48,889 Money market instruments 317,513 — — 317,513 Total short-term investments 347,509 18,893 — 366,402 Other assets: Note receivable — 5,585 — 5,585 Total assets at fair value $ 772,235 $ 2,882,987 $ 8,684 $ 3,732,917 Liabilities Other liabilities: Total return swaps $ — $ 1,589 $ — $ 1,589 Options sold 146 — — 146 Total liabilities at fair value $ 146 $ 1,589 $ — $ 1,735 __________ (1) The fair value is measured using the NAV practical expedient; therefore, it is not categorized within the fair value hierarchy. The fair value amount is presented in this table to permit reconciliation of the fair value hierarchy to the amounts presented in the Company's consolidated balance sheets. December 31, 2016 Level 1 Level 2 Level 3 Total (Amounts in thousands) Assets Fixed maturity securities: U.S. government bonds and agencies $ 12,275 $ — $ — $ 12,275 Municipal securities — 2,449,292 — 2,449,292 Mortgage-backed securities — 39,777 — 39,777 Corporate securities — 189,688 — 189,688 Collateralized loan obligations — 86,525 — 86,525 Other asset-backed securities — 36,996 — 36,996 Total fixed maturity securities 12,275 2,802,278 — 2,814,553 Equity securities: Common stock 316,450 — — 316,450 Non-redeemable preferred stock — 31,809 — 31,809 Private equity funds — — 9,068 9,068 Total equity securities 316,450 31,809 9,068 357,327 Short-term investments: Short-term bonds 70,393 20,233 — 90,626 Money market instruments 285,054 — — 285,054 Total short-term investments 355,447 20,233 — 375,680 Other assets: Total return swaps — 667 — 667 Total assets at fair value $ 684,172 $ 2,854,987 $ 9,068 $ 3,548,227 Liabilities Other liabilities: Total return swaps $ — $ 765 $ — $ 765 Options sold 20 — — 20 Total liabilities at fair value $ 20 $ 765 $ — $ 785 The following tables present the carrying value and fair value of the Company’s financial instruments disclosed, but not carried, at fair value, and the level within the fair value hierarchy at which such instruments are categorized: September 30, 2017 Carrying Value Fair Value Level 1 Level 2 Level 3 (Amounts in thousands) Liabilities Notes payable: Unsecured notes $ 371,236 $ 385,733 $ — $ 385,733 $ — December 31, 2016 Carrying Value Fair Value Level 1 Level 2 Level 3 (Amounts in thousands) Liabilities Notes payable: Secured notes $ 140,000 $ 140,000 $ — $ 140,000 $ — Unsecured notes 180,000 180,000 — 180,000 —
Summary Of Changes In Fair Value Of Level 3 Financial Assets And Financial Liabilities Held At Fair Value	The following table presents a summary of changes in fair value of Level 3 financial assets and financial liabilities: Private Equity Funds Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (Amounts in thousands) Beginning balance $ 8,764 $ 8,972 $ 9,068 $ 10,431 Realized (losses) gains included in earnings (80 ) 564 (384 ) (895 ) Ending balance $ 8,684 $ 9,536 $ 8,684 $ 9,536 The amount of total (losses) gains for the period included in earnings attributable to assets still held at September 30 $ (80 ) $ 564 $ (384 ) $ (895 )

Derivative Financial Instrume24

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
General Discussion of Derivative Instruments and Hedging Activities [Abstract]
Summary Of Location And Amounts Of Derivative Fair Values In The Consolidated Balance Sheets	The following tables present the location and amounts of derivative fair values in the consolidated balance sheets and derivative gains or losses in the consolidated statements of operations: Asset Derivatives Liability Derivatives September 30, 2017 December 31, 2016 September 30, 2017 December 31, 2016 (Amounts in thousands) Total return swaps - Other assets $ — $ 667 $ — $ — Options sold - Other liabilities — — 146 20 Total return swaps - Other liabilities — — 1,589 765 Total derivatives $ — $ 667 $ 1,735 $ 785
Schedule Of Derivative Gains And Losses In The Consolidated Statements Of Operations	Gains (Losses) Recognized in Income Three Months Ended September 30, Nine Months Ended September 30, 2017 2016 2017 2016 (Amounts in thousands) Total return swaps - Net realized investment gains (losses) $ 118 $ 4,172 $ (2,535 ) $ 7,915 Options sold - Net realized investment gains 557 1,030 1,857 3,324 Total $ 675 $ 5,202 $ (678 ) $ 11,239

Goodwill and Other Intangible25

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule Of Components Of Other Intangible Assets	The following table presents the components of other intangible assets: Gross Carrying Amount Accumulated Amortization Net Carrying Amount Useful Lives (Amounts in thousands) (in years) As of September 30, 2017: Customer relationships $ 52,430 $ (42,542 ) $ 9,888 11 Trade names 15,400 (5,615 ) 9,785 24 Technology 4,300 (3,762 ) 538 10 Insurance license 1,400 — 1,400 Indefinite Total other intangible assets, net $ 73,530 $ (51,919 ) $ 21,611 As of December 31, 2016: Customer relationships $ 52,430 $ (39,332 ) $ 13,098 11 Trade names 15,400 (5,133 ) 10,267 24 Technology 4,300 (3,440 ) 860 10 Insurance license 1,400 — 1,400 Indefinite Total other intangible assets, net $ 73,530 $ (47,905 ) $ 25,625
Schedule Of Estimated Future Amortization Expense Related To Intangible Assets	The following table presents the estimated future amortization expense related to other intangible assets as of September 30, 2017 : Year Amortization Expense (Amounts in thousands) Remainder of 2017 $ 1,335 2018 5,335 2019 4,905 2020 758 2021 738 Thereafter 7,140 Total $ 20,211

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2017
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Schedule Of Performance Vesting Restricted Stock Units Granted	The Compensation Committee of the Company’s Board of Directors granted RSU awards to the Company’s senior management and key employees which will vest based upon the Company's performance during three-year performance periods ending on December 31, 2017 and 2018: Grant Year 2016 2015 Three-year performance period ending December 31, 2018 2017 Vesting shares, target (net of forfeited) 84,750 87,250 Vesting shares, maximum (net of forfeited) 158,906 163,594

Losses And Loss Adjustment Ex27

Losses And Loss Adjustment Expense Reserves (Tables)	9 Months Ended
	Sep. 30, 2017
Insurance Loss Reserves [Abstract]
Activity In The Reserves For Losses And Loss Adjustment Expenses	The following table presents the activity in loss and loss adjustment expense reserves: Nine Months Ended September 30, 2017 2016 (Amounts in thousands) Gross reserves at January 1 $ 1,290,248 $ 1,146,688 Less reinsurance recoverable (13,161 ) (14,253 ) Net reserves at January 1 1,277,087 1,132,435 Incurred losses and loss adjustment expenses related to: Current year 1,772,203 1,696,350 Prior years 18,347 69,134 Total incurred losses and loss adjustment expenses 1,790,550 1,765,484 Loss and loss adjustment expense payments related to: Current year 1,099,656 1,065,948 Prior years 606,615 601,379 Total payments 1,706,271 1,667,327 Net reserves at September 30 1,361,366 1,230,592 Reinsurance recoverable 10,798 13,961 Gross reserves at September 30 $ 1,372,164 $ 1,244,553

Notes Payable (Tables)

Notes Payable (Tables)	9 Months Ended
	Sep. 30, 2017
Notes Payable [Abstract]
Schedule of Long-term Debt Instruments	The following table presents information about the Company's notes payable: Lender Interest Rate Maturity Date September 30, 2017 December 31, 2016 (Amounts in thousands) Secured credit facility (1) Bank of America LIBOR plus 40 basis points December 3, 2018 $ — $ 120,000 Secured loan (1) Union Bank LIBOR plus 40 basis points December 3, 2017 — 20,000 Unsecured credit facility (1) Bank of America and Union Bank LIBOR plus 112.5-162.5 basis points December 3, 2019 — 180,000 Senior unsecured notes (2) Publicly traded 4.40% March 15, 2027 375,000 — Unsecured credit facility (3) Bank of America and Wells Fargo Bank LIBOR plus 112.5-162.5 basis points March 29, 2022 — — Total principal amount 375,000 320,000 Less unamortized discount and debt issuance costs (4) 3,764 — Total debt $ 371,236 $ 320,000 __________ (1) On March 8, 2017, the loan and credit facility agreements were terminated and the Company repaid the total outstanding amounts with the proceeds from its public offering of $375 million of senior notes. (2) On March 8, 2017, the Company completed a public debt offering issuing $375 million of senior notes. The notes are unsecured senior obligations of the Company, with a 4.40% annual coupon payable on March 15 and September 15 of each year commencing September 15, 2017. These notes mature on March 15, 2027. The Company used the proceeds from the notes to pay off amounts outstanding under the existing loan and credit facilities and for general corporate purposes. The Company incurred debt issuance costs of approximately $3.4 million , inclusive of underwriters' fees. The notes were issued at a slight discount of 99.847% of par, resulting in the effective annualized interest rate, including debt issuance costs, of approximately 4.45% . (3) On March 29, 2017, the Company entered into an unsecured credit agreement that provides for revolving loans of up to $50 million and matures on March 29, 2022. The interest rates on borrowings under the credit facility are based on the Company's debt to total capital ratio and range from LIBOR plus 112.5 basis points when the ratio is under 15% to LIBOR plus 162.5 basis points when the ratio is greater than or equal to 25%. Commitment fees for the undrawn portions of the credit facility range from 12.5 basis points when the ratio is under 15% to 22.5 basis points when the ratio is greater than or equal to 25%. The debt to total capital ratio is expressed as a percentage of (a) consolidated debt to (b) consolidated shareholders' equity plus consolidated debt. The Company's debt to total capital ratio was 17.4% at September 30, 2017 , resulting in a 15 basis point commitment fee on the $50 million undrawn portion of the credit facility. As of October 26, 2017 , there have been no borrowings under this facility. (4) The unamortized discount and debt issuance costs of approximately $3.8 million are associated with the publicly traded $375 million senior unsecured notes. These are amortized to interest expense over the life of the notes, and the unamortized balance is presented in the Company's consolidated balance sheets as a direct deduction from the carrying amount of the debt. The unamortized debt issuance cost of approximately $0.2 million associated with the $50 million five -year unsecured revolving credit facility maturing on March 29, 2022 is included in other assets in the Company's consolidated balance sheets and amortized to interest expense over the term of the credit facility.

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2017
Segment Reporting [Abstract]
Reconciliation of operating results by reportable segment	The following tables present the Company's operating results by reportable segment: Three Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Net premiums earned $ 792.7 $ 8.5 $ 801.2 $ 780.6 $ 10.3 $ 790.9 Less: Losses and loss adjustment expenses 591.1 4.2 595.3 570.8 5.5 576.3 Underwriting expenses 196.7 3.9 200.6 194.8 4.5 199.3 Underwriting gain 4.9 0.4 5.3 15.0 0.3 15.3 Investment income 31.0 30.3 Net realized investment gains (losses) 20.7 (15.5 ) Other income 5.4 2.4 Interest expense (4.2 ) (0.9 ) Pre-tax income $ 58.2 $ 31.6 Net income $ 46.5 $ 26.9 Nine Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Net premiums earned $ 2,362.4 $ 26.2 $ 2,388.6 $ 2,305.0 $ 32.3 $ 2,337.3 Less: Losses and loss adjustment expenses 1,777.1 13.5 1,790.6 1,748.2 17.3 1,765.5 Underwriting expenses 587.7 11.9 599.6 586.1 13.6 599.7 Underwriting (loss) gain (2.4 ) 0.8 (1.6 ) (29.3 ) 1.4 (27.9 ) Investment income 94.1 91.4 Net realized investment gains 66.3 55.0 Other income 9.7 6.4 Interest expense (10.9 ) (2.9 ) Pre-tax income $ 157.6 $ 122.0 Net income $ 125.1 $ 99.1
Schedule direct premiums attributable to segment	The following tables present the Company’s net premiums earned and direct premiums written by line of insurance business: Three Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Private passenger automobile $ 619.8 $ — $ 619.8 $ 614.0 $ — $ 614.0 Homeowners 108.3 — 108.3 105.5 — 105.5 Commercial automobile 43.6 — 43.6 41.2 — 41.2 Other 21.0 8.5 29.5 19.9 10.3 30.2 Net premiums earned $ 792.7 $ 8.5 $ 801.2 $ 780.6 $ 10.3 $ 790.9 Private passenger automobile $ 633.7 $ — $ 633.7 $ 630.1 $ — $ 630.1 Homeowners 125.8 — 125.8 116.0 — 116.0 Commercial automobile 45.6 — 45.6 41.9 — 41.9 Other 22.9 7.1 30.0 22.4 6.6 29.0 Direct premiums written $ 828.0 $ 7.1 $ 835.1 $ 810.4 $ 6.6 $ 817.0 Nine Months Ended September 30, 2017 2016 Property & Casualty Other Total Property & Casualty Other Total (Amounts in millions) Private passenger automobile $ 1,850.3 $ — $ 1,850.3 $ 1,820.1 $ — $ 1,820.1 Homeowners 322.3 — 322.3 307.0 — 307.0 Commercial automobile 127.3 — 127.3 119.8 — 119.8 Other 62.5 26.2 88.7 58.1 32.3 90.4 Net premiums earned $ 2,362.4 $ 26.2 $ 2,388.6 $ 2,305.0 $ 32.3 $ 2,337.3 Private passenger automobile $ 1,872.8 $ — $ 1,872.8 $ 1,857.3 $ — $ 1,857.3 Homeowners 352.3 — 352.3 331.4 — 331.4 Commercial automobile 133.7 — 133.7 125.2 — 125.2 Other 69.9 21.3 91.2 66.3 20.9 87.2 Direct premiums written $ 2,428.7 $ 21.3 $ 2,450.0 $ 2,380.2 $ 20.9 $ 2,401.1

General (Details)

General (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Aug. 31, 2017USD ($)a	Sep. 30, 2017USD ($)shares	Sep. 30, 2016USD ($)shares	Sep. 30, 2017USD ($)shares	Sep. 30, 2016USD ($)shares
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Potentially dilutive securities (in shares) | shares		0	22,000	0	29,000
Deferred policy acquisition cost amortization		$ 136,290	$ 140,203	$ 416,728	$ 421,685
Advertising expenses				32,000	34,100
Property, Plant and Equipment [Line Items]
Sale of land, gain				$ 3,307	$ 0
Brea, California [Member]
Property, Plant and Equipment [Line Items]
Area of land (in acres) | a	6
Sale of land, sales price	$ 12,200
Sale of land, Promissory note receivable	5,700
Sale of land, gain	$ 3,300
Brea, California [Member] | Note Receivable [Member]
Property, Plant and Equipment [Line Items]
Interest rate	3.50%

Recently Issued Accounting St31

Recently Issued Accounting Standards (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease obligations		$ 27,000
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excess tax benefit adjustment	$ 995
Employee taxes paid for withheld shares adjustment	$ 3,270

Financial Instruments (Narrativ

Financial Instruments (Narrative) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
VIE, implied or unfunded commitments	No	No
VIE, outstanding unfunded commitments	$ 0	$ 0
Liabilities, fair value	1,735,000	785,000
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	1,589,000	765,000
Level 2 [Member] | Secured Notes One [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured notes	0	120,000,000
Level 2 [Member] | Secured Notes Two [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured notes	0	20,000,000
Borrowings [Member] | Unsecured debt [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	385,733,000	180,000,000
Borrowings [Member] | Unsecured debt [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes	375,000,000	180,000,000
Liabilities, fair value	$ 385,733,000	$ 180,000,000

Financial Instruments (Estimate

Financial Instruments (Estimated Fair Values Of Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Liabilities
Liabilities, fair value	$ 1,735	$ 785
Total Return Swap [Member]
Assets
Total assets, fair value	0	667
Call Option [Member]
Liabilities
Liabilities, fair value	146	20
Note Receivable [Member]
Assets
Total assets, fair value	5,585	0
Investments [Member]
Assets
Total assets, fair value	3,727,332	3,547,560
Total Return Swap [Member]
Liabilities
Liabilities, fair value	1,589	765
Borrowings [Member] | Secured Debt [Member]
Liabilities
Liabilities, fair value	0	140,000
Borrowings [Member] | Unsecured debt [Member]
Liabilities
Liabilities, fair value	$ 385,733	$ 180,000

Fair Value Option (Gains And Lo

Fair Value Option (Gains And Losses Due To Changes In Fair Value Of Investments) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Gains (losses) due to changes in fair value of investments	$ 17,608	$ (21,132)	$ 59,740	$ 34,527
Note Receivable [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Gains (losses) due to changes in fair value of investments	(103)	0	(103)	0
Investments [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Gains (losses) due to changes in fair value of investments	17,711	(21,132)	59,843	34,527
Fixed maturity securities [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Gains (losses) due to changes in fair value of investments	9,796	(19,521)	45,705	20,913
Equity Securities [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Gains (losses) due to changes in fair value of investments	7,765	(2,143)	14,227	13,430
Short-term investments [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Gains (losses) due to changes in fair value of investments	$ 150	$ 532	$ (89)	$ 184

Fair Value Measurement (Narrati

Fair Value Measurement (Narrative) (Details)	9 Months Ended
	Sep. 30, 2017USD ($)broker	Dec. 31, 2016USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of portfolio of unadjusted fair values obtained	97.90%
Percentage of portfolio of specific unadjusted broker quotes obtained	0.20%
Commercial Mortgage Backed Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities, fair value disclosure	$ 24,400,000	$ 30,000,000
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of knowledgeable outside security brokers consulted to determine fair value | broker	1
Borrowings [Member] | Unsecured debt [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unsecured notes	$ 375,000,000	180,000,000
Secured Notes One [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured notes	0	120,000,000
Secured Notes Two [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured notes	0	$ 20,000,000
Private Equity Funds, Net Asset Value [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments	$ 0
Private Equity Funds, Net Asset Value [Member] | Equity Securities [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liquidating investment, remaining period	1 year
Private Equity Funds, Net Asset Value [Member] | Equity Securities [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liquidating investment, remaining period	5 years

Fair Value Measurement (Schedul

Fair Value Measurement (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Valuation Techniques) (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	$ 3,732,917,000	$ 3,548,227,000
Liabilities, fair value	1,735,000	785,000
Notes payable	371,236,000	320,000,000
Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	366,402,000	375,680,000
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	772,235,000	684,172,000
Liabilities, fair value	146,000	20,000
Level 1 [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	347,509,000	355,447,000
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	2,882,987,000	2,854,987,000
Liabilities, fair value	1,589,000	765,000
Level 2 [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	18,893,000	20,233,000
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	8,684,000	9,068,000
Liabilities, fair value	0	0
Level 3 [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Note Receivable [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	5,585,000
Note Receivable [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0
Note Receivable [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	5,585,000
Note Receivable [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0
Fixed maturity securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	2,841,736,000	2,814,553,000
Fixed maturity securities [Member] | U.S. Government Bonds and Agencies [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	13,892,000	12,275,000
Fixed maturity securities [Member] | Municipal Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	2,483,750,000	2,449,292,000
Fixed maturity securities [Member] | Mortgage Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	32,726,000	39,777,000
Fixed maturity securities [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	161,883,000	189,688,000
Fixed maturity securities [Member] | Collateralized Loan Obligations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	94,325,000	86,525,000
Fixed maturity securities [Member] | Other Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	55,160,000	36,996,000
Fixed maturity securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	13,892,000	12,275,000
Fixed maturity securities [Member] | Level 1 [Member] | U.S. Government Bonds and Agencies [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	13,892,000	12,275,000
Fixed maturity securities [Member] | Level 1 [Member] | Municipal Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 1 [Member] | Mortgage Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 1 [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 1 [Member] | Collateralized Loan Obligations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 1 [Member] | Other Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	2,827,844,000	2,802,278,000
Fixed maturity securities [Member] | Level 2 [Member] | U.S. Government Bonds and Agencies [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 2 [Member] | Municipal Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	2,483,750,000	2,449,292,000
Fixed maturity securities [Member] | Level 2 [Member] | Mortgage Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	32,726,000	39,777,000
Fixed maturity securities [Member] | Level 2 [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	161,883,000	189,688,000
Fixed maturity securities [Member] | Level 2 [Member] | Collateralized Loan Obligations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	94,325,000	86,525,000
Fixed maturity securities [Member] | Level 2 [Member] | Other Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	55,160,000	36,996,000
Fixed maturity securities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 3 [Member] | U.S. Government Bonds and Agencies [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 3 [Member] | Municipal Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 3 [Member] | Mortgage Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 3 [Member] | Corporate Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 3 [Member] | Collateralized Loan Obligations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Fixed maturity securities [Member] | Level 3 [Member] | Other Asset-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	519,194,000	357,327,000
Equity Securities [Member] | Common Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	410,834,000	316,450,000
Equity Securities [Member] | Nonredeemable Preferred Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	30,665,000	31,809,000
Equity Securities [Member] | Private Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	8,684,000	9,068,000
Equity Securities [Member] | Private Equity Funds, Net Asset Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	69,011,000
Equity Securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	410,834,000	316,450,000
Equity Securities [Member] | Level 1 [Member] | Common Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	410,834,000	316,450,000
Equity Securities [Member] | Level 1 [Member] | Nonredeemable Preferred Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member] | Level 1 [Member] | Private Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	30,665,000	31,809,000
Equity Securities [Member] | Level 2 [Member] | Common Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member] | Level 2 [Member] | Nonredeemable Preferred Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	30,665,000	31,809,000
Equity Securities [Member] | Level 2 [Member] | Private Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	8,684,000	9,068,000
Equity Securities [Member] | Level 3 [Member] | Common Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member] | Level 3 [Member] | Nonredeemable Preferred Stock [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Equity Securities [Member] | Level 3 [Member] | Private Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	8,684,000	9,068,000
Short-term Investments [Member] | Short-term Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	48,889,000	90,626,000
Short-term Investments [Member] | Level 1 [Member] | Short-term Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	29,996,000	70,393,000
Short-term Investments [Member] | Level 2 [Member] | Short-term Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	18,893,000	20,233,000
Short-term Investments [Member] | Level 3 [Member] | Short-term Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Money Market Instruments [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	317,513,000	285,054,000
Money Market Instruments [Member] | Level 1 [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	317,513,000	285,054,000
Money Market Instruments [Member] | Level 2 [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Money Market Instruments [Member] | Level 3 [Member] | Money Market Instruments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value	0	0
Total Return Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value		667,000
Liabilities, fair value	1,589,000	765,000
Total Return Swap [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value		0
Liabilities, fair value	0	0
Total Return Swap [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value		667,000
Liabilities, fair value	1,589,000	765,000
Total Return Swap [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value		0
Liabilities, fair value	0	0
Equity contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	146,000	20,000
Equity contracts [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	146,000	20,000
Equity contracts [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	0	0
Equity contracts [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	0	0
Unsecured debt [Member] | Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	385,733,000	180,000,000
Notes payable	371,236,000	180,000,000
Unsecured debt [Member] | Borrowings [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	0	0
Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	385,733,000	180,000,000
Unsecured debt [Member] | Borrowings [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	0	0
Secured Debt [Member] | Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value	$ 0	140,000,000
Notes payable		140,000,000
Secured Debt [Member] | Borrowings [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value		0
Secured Debt [Member] | Borrowings [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value		140,000,000
Secured Debt [Member] | Borrowings [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities, fair value		$ 0

Fair Value Measurement (Summary

Fair Value Measurement (Summary Of Changes In Fair Value Of Level 3 Financial Assets And Financial Liabilities Held At Fair Value) (Details) - Private Equity Funds [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 8,764	$ 8,972	$ 9,068	$ 10,431
Realized (losses) gains included in earnings	(80)	564	(384)	(895)
Ending Balance	8,684	9,536	8,684	9,536
The amount of total (losses) gains for the period included in earnings attributable to assets still held at September 30	$ (80)	$ 564	$ (384)	$ (895)

Derivative Financial Instrume38

Derivative Financial Instruments (Narrative) (Details) - Swap [Member] - USD ($) $ in Millions	Feb. 13, 2014	Aug. 09, 2013	Sep. 30, 2017	Dec. 31, 2016	Jan. 31, 2017
FFL [Member]
Debt Instrument [Line Items]
Swap agreement collateral			$ 30
Notional amount			$ 98	$ 108
Term of swap agreement	1 year		1 year	1 year
FFL [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.45%		1.28%	1.45%	1.28%
AFL [Member]
Debt Instrument [Line Items]
Swap agreement collateral			$ 40
Notional amount				$ 152
Term of swap agreement		3 years	1 year	1 year
AFL [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate		1.35%	1.28%	1.35%	1.28%

Derivative Financial Instrume39

Derivative Financial Instruments (Summary Of Location And Amounts Of Derivative Fair Values In The Consolidated Balance Sheets) (Details) - Non-hedging derivatives [Member] - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Asset Derivatives	$ 0	$ 667
Liability Derivatives	1,735	785
Total Return Swap [Member] | Other Assets [Member]
Derivative [Line Items]
Asset Derivatives	0	667
Liability Derivatives	0	0
Total Return Swap [Member] | Other liabilities [Member]
Derivative [Line Items]
Asset Derivatives	0	0
Liability Derivatives	1,589	765
Option contracts [Member] | Other liabilities [Member]
Derivative [Line Items]
Asset Derivatives	0	0
Liability Derivatives	$ 146	$ 20

Derivative Financial Instrume40

Derivative Financial Instruments (Schedule Of Derivative Gains And Losses In The Consolidated Statements Of Operations) (Details) - Derivatives Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative [Line Items]
Gain Recognized in Income (Loss)	$ 675	$ 5,202	$ (678)	$ 11,239
Total Return Swap [Member] | Net realized investment (losses) gains [Member]
Derivative [Line Items]
Gain Recognized in Income (Loss)	118	4,172	(2,535)	7,915
Equity contracts [Member] | Net realized investment (losses) gains [Member]
Derivative [Line Items]
Gain Recognized in Income (Loss)	$ 557	$ 1,030	$ 1,857	$ 3,324

Goodwill and Other Intangible41

Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Change in Goodwill	$ 0	$ 0	$ 0	$ 0
Goodwill, impairment	0	0	0	0
Intangible assets amortization expense	$ 1,300,000	$ 1,500,000	$ 4,000,000	$ 4,600,000

Goodwill and Other Intangible42

Goodwill and Other Intangible Assets (Schedule Of Components Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 73,530	$ 73,530
Accumulated Amortization	(51,919)	(47,905)
Total	21,611	25,625
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	52,430	52,430
Accumulated Amortization	(42,542)	(39,332)
Total	$ 9,888	$ 13,098
Useful Lives (in years)	11 years	11 years
Trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 15,400	$ 15,400
Accumulated Amortization	(5,615)	(5,133)
Total	$ 9,785	$ 10,267
Useful Lives (in years)	24 years	24 years
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,300	$ 4,300
Accumulated Amortization	(3,762)	(3,440)
Total	$ 538	$ 860
Useful Lives (in years)	10 years	10 years
Licensing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,400	$ 1,400
Total	$ 1,400	$ 1,400

Goodwill and Other Intangible43

Goodwill and Other Intangible Assets (Schedule Of Estimated Future Amortization Expense Related To Intangible Assets) (Details) $ in Thousands	Sep. 30, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Remainder of 2017	$ 1,335
2,018	5,335
2,019	4,905
2,020	758
2,021	738
Thereafter	7,140
Total	$ 20,211

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		9 Months Ended
	Mar. 31, 2017	Feb. 29, 2016	Sep. 30, 2017	Feb. 28, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period of restricted stock units (in years)			3 years
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period		88,074
Shares withheld for payroll taxes			58,822
Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized				4,900,000
Incentive Award Plan 2015 [Member] | Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant			4,728,000
Shares issued during period			0
Target Restricted Stock Units, 2016 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested options forfeited			11,000
Target Restricted Stock Units, 2015 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested options forfeited			12,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting term (in years)			10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs vested during period		146,896
Restricted Stock [Member] | Incentive Award Plan 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of nonvested shares			172,000
Restricted Stock [Member] | Target Restricted Stock Units, 2014 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vested in period, amount	$ 3.6
RSUs vested during period	61,445

Share-Based Compensation (Sched

Share-Based Compensation (Schedule Of Performance Vesting Restricted Stock Units Granted) (Details) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]
Three-year performance period ending December 31,	2,018	2,017
Vesting shares, target	84,750	87,250
Vesting shares, maximum	158,906	163,594

Income Taxes (Details)

Income Taxes (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)
Components of Income Tax Expense (Benefit), Continuing Operations [Abstract]
Increase in unrecognized tax benefit	$ 38

Losses And Loss Adjustment Ex47

Losses And Loss Adjustment Expense Reserves (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Unusual or Infrequent Item, or Both [Line Items]
Prior years claims and claim adjustment expense	$ 18,347	$ 69,134
Catastrophe [Member]
Unusual or Infrequent Item, or Both [Line Items]
Pre-tax catastrophe losses	$ 59,000	$ 23,000

Losses And Loss Adjustment Ex48

Losses And Loss Adjustment Expense Reserves (Activity In The Reserves For Losses And Loss Adjustment Expenses) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross reserves at January 1	$ 1,290,248	$ 1,146,688
Reissuance recoverable	10,798	13,961	$ 13,161	$ 14,253
Net reserves at January 1	1,277,087	1,132,435
Incurred losses and loss adjustment expense related to:
Current year	1,772,203	1,696,350
Prior years claims and claim adjustment expense	18,347	69,134
Total incurred losses and loss adjustment expenses	1,790,550	1,765,484
Loss and loss adjustment expense payments related to:
Current year	1,099,656	1,065,948
Prior years	606,615	601,379
Total payments	1,706,271	1,667,327
Net reserves at period end	1,361,366	1,230,592
Gross reserves at period end	$ 1,372,164	$ 1,244,553

Notes Payable (Narrative) (Deta

Notes Payable (Narrative) (Details)	Mar. 29, 2017USD ($)	Mar. 08, 2017USD ($)	Sep. 30, 2017USD ($)	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Less unamortized discount and debt issuance costs			$ 3,764,000	$ 0
Unsecured debt [Member]
Debt Instrument [Line Items]
Gross proceeds from issuance of senior notes		$ 375,000,000
Interest rate		4.40%
Debt issuance cost		$ 3,400,000
Debt instrument, discount percent		99.847%
Effective interest rate		4.45%
Secured Notes Two [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Loan maximum borrowing capacity	$ 50,000,000
Revolving credit facility term	5 years
Secured Notes Two [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt to total capital ratio	0.15
Commitment fee on undrawn portion of facility	0.125%		0.15%
Secured Notes Two [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt to total capital ratio	0.25
Commitment fee on undrawn portion of facility	0.225%
Secured Notes Two [Member] | Revolving Credit Facility [Member] | LIBOR [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.125%
Debt to total capital ratio	0.15
Secured Notes Two [Member] | Revolving Credit Facility [Member] | LIBOR [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.625%
Debt to total capital ratio	0.25
Unsecured Notes Three [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility term	5 years
Unamortized debt issuance cost	$ 200,000
Unsecured Notes Three [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt to total capital ratio			0.174
Level 2 [Member] | Secured Notes Two [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			0.40%
Level 2 [Member] | Borrowings [Member] | Unsecured Notes Two [Member] | Unsecured debt [Member]
Debt Instrument [Line Items]
Unsecured debt			$ 375,000,000	$ 0
Interest rate			4.40%
Level 2 [Member] | Borrowings [Member] | Unsecured Notes Three [Member] | Unsecured debt [Member] | LIBOR [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			0.1125%
Level 2 [Member] | Borrowings [Member] | Unsecured Notes Three [Member] | Unsecured debt [Member] | LIBOR [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate			0.1625%

Notes Payable (Schedule of Long

Notes Payable (Schedule of Long-term Debt) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Mar. 08, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Liabilities, fair value	$ 1,735		$ 785
Total principal amount	375,000		320,000
Less unamortized discount and debt issuance costs(4)	3,764		0
Notes payable	371,236		320,000
Level 2 [Member]
Debt Instrument [Line Items]
Liabilities, fair value	1,589		765
Level 2 [Member] | Secured Notes One [Member]
Debt Instrument [Line Items]
Secured notes	0		120,000
Level 2 [Member] | Secured Notes Two [Member]
Debt Instrument [Line Items]
Secured notes	0		20,000
Unsecured debt [Member]
Debt Instrument [Line Items]
Interest rate		4.40%
Unsecured debt [Member] | Borrowings [Member]
Debt Instrument [Line Items]
Liabilities, fair value	385,733		180,000
Notes payable	371,236		180,000
Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member]
Debt Instrument [Line Items]
Liabilities, fair value	385,733		180,000
Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes One [Member]
Debt Instrument [Line Items]
Liabilities, fair value	$ 0		180,000
Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes Two [Member]
Debt Instrument [Line Items]
Interest rate	4.40%
Unsecured debt	$ 375,000		0
Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes Three [Member]
Debt Instrument [Line Items]
Liabilities, fair value	$ 0		$ 0
LIBOR [Member] | Level 2 [Member] | Secured Notes One [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.40%
LIBOR [Member] | Level 2 [Member] | Secured Notes Two [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.40%
LIBOR [Member] | Minimum [Member] | Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes One [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.1125%
LIBOR [Member] | Minimum [Member] | Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes Three [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.1125%
LIBOR [Member] | Maximum [Member] | Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes One [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.1625%
LIBOR [Member] | Maximum [Member] | Unsecured debt [Member] | Borrowings [Member] | Level 2 [Member] | Unsecured Notes Three [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.1625%

Contingencies - Loss Contingenc

Contingencies - Loss Contingencies (Details) - California DOI [Member] - USD ($) $ in Millions	Feb. 09, 2015	Mar. 31, 2015	Nov. 17, 2016
Loss Contingencies [Line Items]
Litigation, penalty assessed	$ 27.6
Payments for assessed penalty		$ 27.6
Penalty interest assessed, statutory rate			7.00%

Contingencies - Gain Contingenc

Contingencies - Gain Contingencies (Details) - USD ($) $ in Millions	Sep. 30, 2017	Jun. 30, 2017
Other liabilities [Member]
Gain Contingencies [Line Items]
Gain contingency	$ 31	$ 30.9

Segment Information - Summary o

Segment Information - Summary of Operating Results by Segment (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)SubsidiaryState	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)SubsidiaryState	Sep. 30, 2016USD ($)
Segment Reporting [Abstract]
Number of insurance companies | Subsidiary	14		14
Number of states in which company operates | State	11		11
Segment Reporting Information [Line Items]
Net premiums earned	$ 801,200	$ 790,900	$ 2,388,600	$ 2,337,300
Losses and loss adjustment expenses	595,290	576,316	1,790,550	1,765,484
Underwriting expenses	200,600	199,300	599,600	599,700
Underwriting gain	5,300	15,300	(1,600)	(27,900)
Net investment income	30,988	30,371	94,058	91,440
Net realized investment gains (losses)	20,718	(15,465)	66,334	54,973
Other	5,446	2,406	9,675	6,416
Interest Expense	(4,191)	(1,012)	(10,873)	(2,922)
Pre-tax income	58,247	31,625	157,598	121,994
Net income	46,485	26,930	125,098	99,126
Property and Casualty Lines [Member]
Segment Reporting Information [Line Items]
Net premiums earned	792,700	780,600	2,362,400	2,305,000
Losses and loss adjustment expenses	591,100	570,800	1,777,100	1,748,200
Underwriting expenses	196,700	194,800	587,700	586,100
Underwriting gain	4,900	15,000	(2,400)	(29,300)
Other Segments [Member]
Segment Reporting Information [Line Items]
Net premiums earned	8,500	10,300	26,200	32,300
Losses and loss adjustment expenses	4,200	5,500	13,500	17,300
Underwriting expenses	3,900	4,500	11,900	13,600
Underwriting gain	$ 400	$ 300	$ 800	$ 1,400

Segment Information - Summary54

Segment Information - Summary of Premiums Written and Earned by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net premiums earned	$ 801.2	$ 790.9	$ 2,388.6	$ 2,337.3
Direct Premiums Written	835.1	817	2,450	2,401.1
Private Passenger Automobile Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	619.8	614	1,850.3	1,820.1
Direct Premiums Written	633.7	630.1	1,872.8	1,857.3
Homeowners Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	108.3	105.5	322.3	307
Direct Premiums Written	125.8	116	352.3	331.4
Commercial Automobile Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	43.6	41.2	127.3	119.8
Direct Premiums Written	45.6	41.9	133.7	125.2
Other [Member]
Segment Reporting Information [Line Items]
Net premiums earned	29.5	30.2	88.7	90.4
Direct Premiums Written	30	29	91.2	87.2
Property and Casualty Lines [Member]
Segment Reporting Information [Line Items]
Net premiums earned	792.7	780.6	2,362.4	2,305
Direct Premiums Written	828	810.4	2,428.7	2,380.2
Property and Casualty Lines [Member] | Private Passenger Automobile Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	619.8	614	1,850.3	1,820.1
Direct Premiums Written	633.7	630.1	1,872.8	1,857.3
Property and Casualty Lines [Member] | Homeowners Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	108.3	105.5	322.3	307
Direct Premiums Written	125.8	116	352.3	331.4
Property and Casualty Lines [Member] | Commercial Automobile Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	43.6	41.2	127.3	119.8
Direct Premiums Written	45.6	41.9	133.7	125.2
Property and Casualty Lines [Member] | Other [Member]
Segment Reporting Information [Line Items]
Net premiums earned	21	19.9	62.5	58.1
Direct Premiums Written	22.9	22.4	69.9	66.3
Other Segments [Member]
Segment Reporting Information [Line Items]
Net premiums earned	8.5	10.3	26.2	32.3
Direct Premiums Written	7.1	6.6	21.3	20.9
Other Segments [Member] | Private Passenger Automobile Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	0	0	0	0
Direct Premiums Written	0	0	0	0
Other Segments [Member] | Homeowners Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	0	0	0	0
Direct Premiums Written	0	0	0	0
Other Segments [Member] | Commercial Automobile Line [Member]
Segment Reporting Information [Line Items]
Net premiums earned	0	0	0	0
Direct Premiums Written	0	0	0	0
Other Segments [Member] | Other [Member]
Segment Reporting Information [Line Items]
Net premiums earned	8.5	10.3	26.2	32.3
Direct Premiums Written	$ 7.1	$ 6.6	$ 21.3	$ 20.9

Subsequent Event (Details)

Subsequent Event (Details) - Wildfire [Member] - Subsequent Event [Member] $ in Millions	Oct. 15, 2017USD ($)structure
Subsequent Event [Line Items]
Structures destroyed | structure	100
Reinsurance recoverables	$ 10
Reinstatement premium, maximum	19
Minimum [Member]
Subsequent Event [Line Items]
Pre-tax catastrophe losses	60
Maximum [Member]
Subsequent Event [Line Items]
Pre-tax catastrophe losses	$ 100
Reinsurance Policy, Up To Two Hundred Million [Member]
Subsequent Event [Line Items]
Reinsurance retention policy, reinsured risk, percentage	100.00%
Reinsurance retention policy, excess retention, amount reinsured	$ 190
Reinsurance retention policy, retention	$ 10
Reinsurance Policy, Above Two Hundred Million [Member]
Subsequent Event [Line Items]
Reinsurance retention policy, reinsured risk, percentage	5.00%
Reinsurance retention policy, retention	$ 15
Reinsurance retention policy, lower limit	$ 200
Reinsurance retention policy, retention, percentage	95.00%
Northern California
Subsequent Event [Line Items]
Structures destroyed | structure	8,000