W. R. Berkley (WRB) 10-K 22 Feb 16 2015 FY Annual report Financial data

Document and Entity Informatio

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 17, 2016	Jun. 30, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	BERKLEY W R CORP
Entity Central Index Key	11,544
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		122,586,752
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 5,048,029,512

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
REVENUES:
Net premiums written	$ 6,189,515	$ 5,996,947	$ 5,500,173
Change in net unearned premiums	(148,906)	(252,529)	(273,636)
Net premiums earned	6,040,609	5,744,418	5,226,537
Net investment income	512,645	600,885	544,291
Insurance service fees	139,440	117,443	107,513
Net investment gains:
Net realized gains on investment sales	125,633	254,852	127,586
Other-than-temporary impairments	(33,309)	0	(6,042)
Net investment gains	92,324	254,852	121,544
Revenues from wholly-owned investees	421,102	410,022	407,623
Other income	337	1,308	1,026
Total revenues	7,206,457	7,128,928	6,408,534
OPERATING COSTS AND EXPENSES:
Losses and loss expenses	3,656,270	3,490,567	3,197,024
Other operating costs and expenses	2,289,750	2,157,456	2,000,684
Expenses from wholly-owned investees	397,461	400,535	388,761
Interest expense	130,946	128,174	123,177
Total operating costs and expenses	6,474,427	6,176,732	5,709,646
Income before income taxes	732,030	952,196	698,888
Income Tax expense	(227,923)	(302,593)	(193,587)
Net income before noncontrolling interests	504,107	649,603	505,301
Noncontrolling interests	(413)	(719)	(5,376)
Net income to common stockholders	$ 503,694	$ 648,884	$ 499,925
NET INCOME PER SHARE:
Basic (dollars per share)	$ 4.06	$ 5.07	$ 3.69
Diluted (dollars per share)	$ 3.87	$ 4.86	$ 3.55

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Investments:
Fixed maturity securities	$ 12,444,394	$ 12,705,160
Equity securities available for sale	150,866	170,991
Arbitrage trading account	376,697	450,648
Loans receivable	273,103	322,012
Investment funds	1,170,040	1,211,401
Equity securities available for sale	936,367	731,612
Total investments	15,351,467	15,591,824
Cash and cash equivalents	763,631	674,441
Premiums and fees receivable	1,669,186	1,651,088
Due from reinsurers	1,532,829	1,503,441
Accrued investment income	123,164	120,367
Prepaid reinsurance premiums	394,387	395,748
Deferred policy acquisition costs	513,128	488,525
Property, furniture and equipment	348,224	332,098
Goodwill	153,291	150,944
Accrued investment income	383,115	371,034
Current federal and foreign income taxes	55,763	67,623
Other assets	442,782	369,558
Total assets	21,730,967	21,716,691
Liabilities:
Reserves for losses and loss expenses	10,669,150	10,369,701
Unearned premiums	3,137,133	3,026,732
Due to reinsurers	224,752	237,270
Trading account securities sold but not yet purchased	37,035	106,079
Deferred federal and foreign income taxes	6,811	37,452
Other liabilities	837,937	859,736
Subordinated debentures	340,320	340,060
Senior notes and other debt	1,844,621	2,115,527
Total liabilities	17,097,759	17,092,557
Equity:
Preferred stock, par value $.10 per share: Authorized 5,000,000 shares; issued and outstanding - none	0	0
Common stock, par value $.20 per share: Authorized 500,000,000 shares, issued and outstanding, net of treasury shares, 132,233,167 and 136,017,732 shares, respectively	47,024	47,024
Additional paid-in capital	1,005,455	991,512
Retained earnings	6,178,070	5,732,410
Accumulated other comprehensive income (loss)	(66,698)	183,550
Treasury stock, at cost, 111,810,081 and 108,369,082 shares, respectively	(2,563,605)	(2,364,551)
Total common stockholders’ equity	4,600,246	4,589,945
Noncontrolling interests	32,962	34,189
Total equity	4,633,208	4,624,134
Total liabilities and equity	$ 21,730,967	$ 21,716,691

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value (dollars per share)	$ 0.10	$ 0.10
Preferred stock, authorized (shares)	5,000,000	5,000,000
Preferred stock, issued (shares)	0	0
Preferred stock, outstanding (shares)	0	0
Common stock, par value (dollars per share)	$ 0.20	$ 0.20
Common stock, authorized (shares)	500,000,000	500,000,000
Common stock, issued (shares)	123,307,837	126,748,836
Common stock, outstanding (shares)	123,307,837	126,748,836
Treasury stock, at cost (shares)	111,810,081	108,369,082

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common stocks	Additional Paid In Capital	Retained Earnings	Accumulated Other Comprehensive Income	Unrealized Investment gains (losses)	Currency translation adjustments	Net pension asset	Treasury Stock	Noncontrolling Interests
Beginning of period at Dec. 31, 2012		$ 47,024	$ 945,166	$ 4,817,807		$ 517,658	$ (36,676)	$ (15,351)	$ (1,969,411)	$ 29,249
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised and restricted units issued including tax benefit			(1,143)
Restricted stock units expensed			22,881
Stock issued			536						597
Net income (loss)	$ 505,301			499,925						5,376
Dividends				(52,717)
Unrealized gains (losses) on securities not other-than-temporarily impaired	(261,064)					(261,791)
Unrealized gains (losses) on other-than-temporarily impaired securities						699
Net change in period	(23,848)						(23,848)
Net change in period	8,700							8,700
Stock exercised/vested									2,452
Stock repurchased									(166,473)
Acquisition (sale) of noncontrolling interest										(1,294)
Other comprehensive income, net of tax	(276,212)									28
End of period at Dec. 31, 2013		47,024	967,440	5,265,015	$ 189,391	256,566	(60,524)	(6,651)	(2,132,835)	33,359
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised and restricted units issued including tax benefit			(4,485)
Restricted stock units expensed			27,966
Stock issued			591						594
Net income (loss)	649,603			648,884						719
Dividends				(181,489)
Unrealized gains (losses) on securities not other-than-temporarily impaired	49,666					49,071
Unrealized gains (losses) on other-than-temporarily impaired securities						562
Net change in period	(62,125)						(62,125)
Net change in period	6,651							6,651
Stock exercised/vested									6,623
Stock repurchased									(238,933)
Acquisition (sale) of noncontrolling interest										78
Other comprehensive income, net of tax	(5,808)				(5,808)		(62,125)	6,651		33
End of period at Dec. 31, 2014	4,624,134	47,024	991,512	5,732,410	183,550	306,199	(122,649)	0	(2,364,551)	34,189
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised and restricted units issued including tax benefit			(17,456)
Restricted stock units expensed			30,691
Stock issued			708						623
Net income (loss)	504,107			503,694						413
Dividends				(58,034)
Unrealized gains (losses) on securities not other-than-temporarily impaired	(125,542)					(113)
Unrealized gains (losses) on other-than-temporarily impaired securities						(125,391)
Net change in period	(124,744)						(124,744)
Net change in period	0							0
Stock exercised/vested									23,975
Stock repurchased									(223,652)
Acquisition (sale) of noncontrolling interest										(1,602)
Other comprehensive income, net of tax	(250,286)				(250,286)		(124,744)	0		(38)
End of period at Dec. 31, 2015	$ 4,633,208	$ 47,024	$ 1,005,455	$ 6,178,070	$ (66,698)	$ 180,695	$ (247,393)	$ 0	$ (2,563,605)	$ 32,962

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income before noncontrolling interests	$ 504,107	$ 649,603	$ 505,301
Other comprehensive income:
Change in unrealized translation adjustments	(124,744)	(62,125)	(23,848)
Change in unrealized investment gains (losses), net of taxes	(125,542)	49,666	(261,064)
Change in unrecognized pension obligation, net of taxes	0	6,651	8,700
Other comprehensive loss	(250,286)	(5,808)	(276,212)
Comprehensive income	253,821	643,795	229,089
Comprehensive income to the noncontrolling interest	(375)	(752)	(5,404)
Comprehensive income to common shareholders	$ 253,446	$ 643,043	$ 223,685

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CASH FROM OPERATING ACTIVITIES:
Net income to common stockholders	$ 503,694	$ 648,884	$ 499,925
Adjustments to reconcile net income to net cash from operating activities:
Net investment gains	(92,324)	(254,852)	(121,544)
Depreciation and amortization	85,139	88,836	103,090
Noncontrolling interests	413	719	5,376
Investment funds	(62,228)	(131,649)	(67,712)
Stock incentive plans	32,123	28,068	23,784
Change in:
Arbitrage trading account	(7,173)	(50,817)	(10,324)
Premiums and fees receivable	(60,942)	(104,174)	(138,027)
Reinsurance accounts	(31,930)	(33,445)	(171,263)
Deferred policy acquisition costs	(29,860)	(42,789)	(52,124)
Increase (Decrease) in Income Taxes	20,428	(40,935)	(45,613)
Current Income Tax Expense (Benefit)	176,832	271,306	139,164
Deferred income taxes	47,260	30,812	56,281
Reserves for losses and loss expenses	397,685	376,617	372,002
Unearned premiums	142,699	277,826	323,160
Other	(63,680)	(58,254)	42,787
Net cash from operating activities	881,304	734,847	819,798
CASH FLOWS USED IN INVESTING ACTIVITIES:
Proceeds from sale of fixed maturity securities	1,388,680	633,459	1,344,707
Proceeds from sale of equity securities	15,833	113,251	267,554
Distributions from (contributions to) investment funds	177,424	69,319	(236,580)
Proceeds from maturities and prepayments of fixed maturity securities	2,999,339	2,605,839	2,718,156
Purchase of fixed maturity securities	(4,455,223)	(4,292,165)	(4,198,135)
Purchase of equity securities	(29,526)	(31,207)	(156,557)
Real estate purchased	(222,659)	(213,159)	(107,352)
Proceeds from Sale of Buildings	0	343,723	0
Change in loans receivable	48,909	21,608	(30,974)
Net additions to property, furniture and equipment	(63,562)	(41,958)	(63,150)
Change in balances due from security brokers	(22,666)	32,617	(26,155)
Proceeds from Divestiture of Businesses, Net of Cash Divested	0	15,783
Payment for business purchased, net of cash acquired	(7,312)	(65,421)	(56,878)
Net cash used in investing activities	(170,763)	(808,311)	(545,364)
CASH FLOWS USED IN FINANCING ACTIVITIES:
Net proceeds from issuance of debt	9,056	354,012	346,822
Net proceeds from stock options exercised	0	0	53
Repayment of senior notes and other debt	(281,086)	(3,700)	(465,389)
Cash dividends to common stockholders	(58,034)	(181,489)	(52,717)
Purchase of common treasury shares	(223,652)	(238,933)	(166,473)
Other	(1,602)	337	7,442
Net cash used in financing activities	(555,318)	(69,773)	(330,262)
Net impact on cash due to change in foreign exchange rates	(66,033)	(22,060)	(10,104)
Net increase (decrease) in cash and cash equivalents	89,190	(165,297)	(65,932)
Cash and cash equivalents at beginning of year	674,441	839,738	905,670
Cash and cash equivalents at end of year	$ 763,631	$ 674,441	$ 839,738

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies (A) Principles of consolidation and basis of presentation The consolidated financial statements, which include the accounts of W. R. Berkley Corporation and its subsidiaries (the "Company"), have been prepared on the basis of U.S. generally accepted accounting principles ("GAAP"). All significant intercompany transactions and balances have been eliminated. Reclassifications have been made in the 2014 and 2013 financial statements to conform to the presentation of the 2015 financial statements. 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 and disclosures of contingent assets and liabilities at the date of the financial statements and the revenues and expenses reflected during the reporting period. The most significant items on our balance sheet that involve a greater degree of accounting estimates that are subject to change in the future are the valuation of investments, other-than-temporary impairments, loss and loss expense reserves and premium estimates. Actual results could differ from those estimates. (B) Revenue recognition Insurance premiums are recognized as written at the inception of the policy. Reinsurance premiums are estimated based upon information received from ceding companies, and subsequent differences from such estimates are recorded in the period they are determined. Insurance and reinsurance premiums are primarily earned on a pro rata basis over the policy term. Fees for services are earned over the period that the services are provided. Audit premiums are recognized when they are reliably determinable. The change in accruals for earned but unbilled audit premiums increased net premiums written and premiums earned by $3 million , $9 million and $12 million in 2015 , 2014 and 2013 , respectively. Revenues from wholly-owned investees are derived from aircraft services provided to the general, commercial and military aviation markets. These services include (i) the distribution, manufacturing, repair and overhaul of aircraft parts and components, (ii) the sale of new and used aircraft, and (iii) avionics, fuel, maintenance, storage and charter services. Revenue is recognized upon the shipment of parts, the delivery of aircraft, the delivery of fuel, and upon completion of services. Insurance service fee revenue represents servicing fees for program administration and claims management services provided by the Company, including workers compensation assigned risk plans, as well as insurance brokerage and risk management services. Fees for program administration, claims management and risk management services are primarily recognized ratably over the related contract period for which the underlying services are rendered. Commissions for insurance brokerage are generally recognized when the underlying insurance policy is effective. (C) Cash and cash equivalents Cash equivalents consist of funds invested in money market accounts and investments with an effective maturity of three months or less when purchased. (D) Investments Fixed maturity securities classified as available for sale are carried at estimated fair value, with unrealized gains and losses, net of applicable income taxes, excluded from earnings and reported as a component of comprehensive income and a separate component of stockholders' equity. Fixed maturity securities that the Company has the positive intent and ability to hold to maturity are classified as held to maturity and reported at amortized cost. Investment income from fixed maturity securities is recognized based on the constant effective yield method. Premiums and discounts on mortgage-backed securities are adjusted for the effects of actual and anticipated prepayments on a retrospective basis. Equity securities classified as available for sale are carried at estimated fair value, with unrealized gains and losses, net of applicable income taxes, excluded from earnings and reported as a component of comprehensive income and a separate component of stockholders' equity. Equity and fixed maturity securities that the Company purchased with the intent to sell in the near-term are classified as trading account securities and are reported at estimated fair value. Realized and unrealized gains and losses from trading activity are reported as net investment income and are recorded at the trade date. Short sales and short call options are presented as trading securities sold but not yet purchased. Unsettled trades and the net margin balances held by the clearing broker are presented as a trading account receivable from brokers and clearing organizations. Investment funds are carried under the equity method of accounting. For certain investment funds, the Company's share of the earnings or losses is reported on a one-quarter lag in order to facilitate the timely completion of the Company's consolidated financial statements. Loans receivable primarily represent commercial real estate mortgage loans and bank loans and are carried at amortized cost. The Company monitors the performance of its loans receivable and establishes an allowance for loan losses for loans where the Company determines it is probable that the contractual terms will not be met, with a corresponding charge to earnings. For loans that are evaluated individually and deemed to be impaired, the Company establishes a specific allowance based on a discounted cash flow analysis and comparable cost and sales methodologies, if appropriate. Individual loans that are not considered impaired and smaller-balance homogeneous loans are evaluated collectively and a general allowance is established if it is considered probable that a loss has been incurred. The accrual of interest on loans receivable is discontinued if the loan is 90 days past due based on the contractual terms of the loan unless the loan is adequately secured and in process of collection. In general, loans are placed on non-accrual status or charged off at an earlier date if collection of principal or interest is considered doubtful. Interest on these loans is accounted for on a cash basis until qualifying for return to accrual status. Loans are returned to accrual status when all principal and interest amounts contractually due are brought current and future payments are reasonably assured. Fair value is defined as “the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.” Fair value of investments is determined based on a fair value hierarchy that prioritizes the use of observable inputs over the use of unobservable inputs and requires the use of observable inputs when available. (See Note 13 of the Notes to Consolidated Financial Statements.) Realized gains or losses represent the difference between the cost of securities sold and the proceeds realized upon sale and are recorded at the trade date. The Company uses primarily the first-in, first-out method to determine the cost of securities sold. The cost of securities is adjusted where appropriate to include a provision for a decline in value which is considered to be other than temporary. An other-than-temporary decline is considered to occur in investments where there has been a sustained reduction in fair value and where the Company does not expect to recover the cost basis of the investment prior to the time of sale or maturity. Since equity securities do not have a contractual cash flow or a maturity, the Company considers whether the price of an equity security is expected to recover within a reasonable period of time. For fixed maturity securities that the Company intends to sell or, more likely than not, would be required to sell, a decline in value below amortized cost is considered to be an other-than-temporary impairment (“OTTI”). The amount of OTTI is equal to the difference between amortized cost and fair value at the balance sheet date. For fixed maturity securities that the Company does not intend to sell or believes that it is more likely than not it would not be required to sell, a decline in value below amortized cost is considered to be an OTTI if the Company does not expect to recover the entire amortized cost basis of a security (i.e., the present value of cash flows expected to be collected is less than the amortized cost basis of the security). The portion of the decline in value considered to be a credit loss (i.e., the difference between the present value of cash flows expected to be collected and the amortized cost basis of the security) is recognized in earnings. The portion of the decline in value not considered to be a credit loss (i.e., the difference in the present value of cash flows expected to be collected and the fair value of the security) is recognized in other comprehensive income. Impairment assessments for structured securities, including mortgage-backed securities and asset-backed securities, collateralized debt obligations and corporate debt, are generally evaluated based on the performance of the underlying collateral under various economic and default scenarios that may involve subjective judgments and estimates by management. Modeling these securities involves various factors, such as projected default rates, the nature and realizable value of the collateral, if any, the ability of the issuer to make scheduled payments, historical performance and other relevant economic and performance factors. If an OTTI determination is made, a discounted cash flow analysis is used to ascertain the amount of the credit impairment. Real estate held for investment purposes is initially recorded at the purchase price, which is generally fair value, and is subsequently reported at cost less accumulated depreciation. Real estate taxes, interest and other costs incurred during development and construction are capitalized. Buildings are depreciated on a straight-line basis over the estimated useful lives of the building. Minimum rental income is recognized on a straight-line basis over the lease term. Income and expenses from real estate are reported as net investment income. The carrying value of real estate is reviewed for impairment and an impairment loss is recognized if the estimated undiscounted cash flows from the use and disposition of the property are less than the carrying value of the property. (E) Per share data The Company presents both basic and diluted net income per share (“EPS”) amounts. Basic EPS is calculated by dividing net income by weighted average number of common shares outstanding during the year. Diluted EPS is based upon the weighted average number of common and common equivalent shares outstanding during the year and is calculated using the treasury stock method for stock incentive plans. Common equivalent shares are excluded from the computation in periods in which they have an anti-dilutive effect. Stock options for which the exercise price exceeds the average market price over the period have an anti-dilutive effect on EPS and, accordingly, are excluded from the calculation. (F) Deferred policy acquisition costs Acquisition costs associated with the successful acquisition of new and renewed insurance and reinsurance contracts are deferred and amortized ratably over the terms of the related contracts. Ceding commissions received on reinsurance contracts are netted against acquisition costs and are recognized ratably over the life of the contract. Deferred policy acquisition costs are presented net of unearned ceding commissions. Deferred policy acquisition costs are comprised primarily of commissions, as well as employment-related underwriting costs and premium taxes. Deferred policy acquisition costs are reviewed to determine if they are recoverable from future income and, if not, are charged to expense. The recoverability of deferred policy acquisition costs is evaluated separately by each of our operating companies for each of their major lines of business. Future investment income is taken into account in measuring the recoverability of deferred policy acquisition costs. (G) Reserves for losses and loss expenses Reserves for losses and loss expenses are an accumulation of amounts determined on the basis of (1) evaluation of claims for business written directly by the Company; (2) estimates received from other companies for reinsurance assumed by the Company; and (3) estimates for losses incurred but not reported (based on Company and industry experience). These estimates are periodically reviewed and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments are reflected in the statements of income in the period in which they are determined. The Company discounts its reserves for excess and assumed workers' compensation claims using a risk-free or statutory rate. (See Note 14 of Notes to Consolidated Financial Statements.) (H) Reinsurance ceded The unearned portion of premiums ceded to reinsurers is reported as prepaid reinsurance premiums and earned ratably over the policy term. The estimated amounts of reinsurance recoverable on unpaid losses are reported as due from reinsurers. To the extent any reinsurer does not meet its obligations under reinsurance agreements, the Company must discharge its liability. Amounts due from reinsurers are reflected net of funds held where the right of offset is present. The Company has provided reserves for estimated uncollectible reinsurance. (I) Deposit accounting Contracts that do not meet the risk transfer requirements of GAAP are accounted for using the deposit accounting method. Under this method, an asset or liability is recognized at the inception of the contract based on consideration paid or received. The amount of the deposit asset or liability is adjusted at subsequent reporting dates using the interest method with a corresponding credit or charge to interest income or expense. Deposit liabilities for assumed reinsurance contracts were $54 million and $68 million at December 31, 2015 and 2014 , respectively. (J) Federal and foreign income taxes The Company files a consolidated income tax return in the U.S. and foreign tax returns in countries where it has overseas operations. The Company's method of accounting for income taxes is the asset and liability method. Under this method, deferred tax assets and liabilities are measured using tax rates currently in effect or expected to apply in the years in which those temporary differences are expected to reverse. Interest and penalties, if any, are reported as income tax expense. The Company believes there are no tax positions that would require disclosure under GAAP. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that all or a portion of the deferred tax assets will not be realized. (K) Foreign currency Gains and losses resulting from foreign currency transactions (transactions denominated in a currency other than the entity's functional currency) are reported on the statements of income as other operating costs and expenses. Unrealized gains or losses resulting from translating the results of non-U.S. dollar denominated operations are reported in accumulated other comprehensive income. Revenues and expenses denominated in currencies other than U.S. dollars are translated at the weighted average exchange rate during the year. Assets and liabilities are translated at the rate of exchange in effect at the balance sheet date. (L) Property, furniture and equipment Property, furniture and equipment are carried at cost less accumulated depreciation. Depreciation is calculated using the estimated useful lives of the respective assets. Depreciation expense was $45 million , $44 million and $38 million for 2015 , 2014 and 2013 , respectively. (M) Comprehensive income Comprehensive income encompasses all changes in stockholders' equity (except those arising from transactions with stockholders) and includes net income, net unrealized holding gains or losses on available for sale securities, unrealized foreign currency translation adjustments and changes in unrecognized pension obligations. (N) Goodwill and other intangible assets Goodwill and other intangible assets are tested for impairment on an annual basis and at interim periods where circumstances require. The Company's impairment test as of December 31, 2015 indicated that there were no impairment losses related to goodwill and other intangible assets. Intangible assets of $94 million and $96 million are included in other assets as of December 31, 2015 and 2014 , respectively. (O) Stock options The costs resulting from all share-based payment transactions with employees are recognized in the consolidated financial statements using a fair-value-based measurement method. Compensation cost is recognized for financial reporting purposes over the period in which the employee is required to provide service in exchange for the award (generally the vesting period). (P) Statements of cash flows Interest payments were $130 million , $120 million and $125 million in 2015 , 2014 and 2013, respectively. Income taxes paid were $165 million , $314 million and $186 million in 2015 , 2014 and 2013 , respectively. Other non-cash items include acquisitions, unrealized investment gains and losses and pension expense. (See Note 2, Note 11 and Note 25 of Notes to Consolidated Financial Statements.) (Q) Recent accounting pronouncements The accounting and reporting standards that became effective in 2015 were either not applicable to the Company or their adoption did not have a material impact on the Company. Accounting and reporting standards that are not yet effective: In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, Revenue from Customers. ASU 2014-09 clarifies the principles for recognizing revenue. While insurance contracts are not within the scope of this updated guidance, the Company’s insurance service fee revenue will be subject to this updated guidance. The updated guidance requires an entity to recognize revenue as performance obligations are met, in order to reflect the transfer of promised goods or services to customers in an amount that reflects the consideration the entity is entitled to receive for those goods or services. The updated guidance, as amended by ASU 2015-14, is effective for public business entities for annual and interim reporting periods beginning after December 15, 2017. The adoption of this guidance is not expected to have a material effect on the Company’s financial condition or results of operations. In February 2015, the FASB issued ASU 2015-02, Consolidation. ASU 2015-02 makes targeted amendments to the current consolidation accounting guidance, in response to accounting complexity concerns. The guidance simplifies consolidation accounting by reducing the number of approaches to consolidation. The updated guidance is effective for annual and interim reporting periods beginning after December 15, 2015. The adoption of this guidance is not expected to have a material effect on the Company’s financial condition or results of operations, but will result in additional disclosures. In May 2015, the FASB issued ASU 2015-09, Disclosures about Short-Duration Contracts. ASU 2015-09 requires companies that issue short duration insurance contracts to disclose additional information, including: (i) incurred and paid claims development tables; (ii) frequency and severity of claims; and (iii) information about material changes in judgments made in calculating the liability for unpaid claim adjustment expenses, including reasons for the change and the effects on the financial statements. ASU 2015-09 is effective for annual periods beginning after December 15, 2015, and interim periods within annual periods beginning after December 15, 2016. The amendments in ASU 2015-09 should be applied retrospectively by providing comparative disclosures for each period presented, except for those requirements that apply only to the current period. As the requirements of this literature are disclosure only, the adoption of this guidance will not impact our financial condition or results of operations. In January 2016, the FASB issued ASU 2016-01, Financial Instruments. ASU 2016-01 amends the accounting guidance for financial instruments to require all equity investments to be measured at fair value with changes in the fair value recognized through net income (other than those accounted for under equity method of accounting or those that result in consolidation of the investee). The updated guidance is effective for public business entities for annual reporting periods beginning after December 15, 2017 and interim periods within those years. The adoption of this guidance is not expected to have a material effect on the Company’s financial condition upon adoption, but will impact results of operations after adoption of this guidance as unrealized gains and losses on equity securities will no longer be reported directly in AOCI, but will instead be reported in net income. All other recently issued but not yet effective accounting and reporting standards are either not applicable to the Company or are not expected to have a material impact on the Company.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Acquisitions	Acquisitions / Dispositions In 2015, the Company acquired an aviation systems company for $8 million . In 2014, the Company acquired a specialty property and casualty insurance distribution company for $83 million . The fair values of the assets acquired and liabilities assumed have been estimated based on a valuation prepared by a third party. The estimated useful lives of the intangible assets acquired range from 7 years to 15 years, with approximately $10 million having an indefinite life. In 2014, the Company sold an aviation-related business for $ 16 million . The business had a net carrying value of $ 15 million , comprised of $7 million of goodwill, $6 million of other assets, $4 million of furniture and equipment and $2 million of liabilities. The following table summarizes the estimated fair value of net assets acquired and liabilities assumed for the business combination completed in 2014 : (In thousands) 2014 Cash and cash equivalents $ 17,457 Real estate, furniture and equipment 669 Goodwill and other intangibles assets 79,646 Premium and service fee receivable 24,432 Other assets 2,590 Total assets acquired 124,794 Deferred federal income tax (7,107 ) Debt — Other liabilities assumed (34,809 ) Net assets acquired $ 82,878

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Consolidated Statement of Comprehensive Income (Loss)	Consolidated Statement of Comprehensive Income (Loss) The following table presents the components of the changes in accumulated other comprehensive income (loss) (AOCI) as of and for the year ended December 31, 2015 : (In thousands) Unrealized investment gains (losses) Currency translation adjustments Net pension asset Accumulated other comprehensive income (loss) Changes in AOCI Beginning of period $ 306,199 $ (122,649 ) $ — $ 183,550 Other comprehensive income (loss) before reclassifications (119,994 ) (124,744 ) — (244,738 ) Amounts reclassified from AOCI (5,548 ) — — (5,548 ) Other comprehensive income (loss) (125,542 ) (124,744 ) — (250,286 ) Unrealized investment gain related to non-controlling interest 38 — — 38 Ending balance $ 180,695 $ (247,393 ) $ — $ (66,698 ) Amounts reclassified from AOCI Pre-tax $ (8,535 ) (1) $ — $ — $ (8,535 ) Tax effect 2,987 (2) — — 2,987 After-tax amounts reclassified $ (5,548 ) $ — $ — $ (5,548 ) Other comprehensive income (loss) Pre-tax $ (192,186 ) $ (124,744 ) $ — $ (316,930 ) Tax effect 66,644 — — 66,644 Other comprehensive income (loss) $ (125,542 ) $ (124,744 ) $ — $ (250,286 ) The following table presents the components of the changes in accumulated other comprehensive income (loss) (AOCI) as of and for the year ended December 31, 2014 : (In thousands) Unrealized investment gains (losses) Currency translation adjustments Net pension asset Accumulated other comprehensive income (loss) Changes in AOCI Beginning of period $ 256,566 $ (60,524 ) $ (6,651 ) $ 189,391 Other comprehensive income (loss) before reclassifications 98,294 (62,125 ) — 36,169 Amounts reclassified from AOCI (48,628 ) — 6,651 (41,977 ) Other comprehensive income (loss) 49,666 (62,125 ) 6,651 (5,808 ) Unrealized investment gain related to non-controlling interest (33 ) — — (33 ) Ending balance $ 306,199 $ (122,649 ) $ — $ 183,550 Amounts reclassified from AOCI Pre-tax $ (74,812 ) (1) $ — $ 10,232 (3) $ (64,580 ) Tax effect 26,184 (2) — (3,581 ) (2) 22,603 After-tax amounts reclassified $ (48,628 ) $ — $ 6,651 $ (41,977 ) Other comprehensive income (loss) Pre-tax $ 72,889 $ (62,125 ) $ 10,232 $ 20,996 Tax effect (23,223 ) — (3,581 ) (26,804 ) Other comprehensive income (loss) $ 49,666 $ (62,125 ) $ 6,651 $ (5,808 ) _______________ (1) Net investment gains in the consolidated statements of income. (2) Income tax expense in the consolidated statements of income. (3) Other operating costs and expenses in the consolidated statements of income.

Investments In Fixed Maturity S

Investments In Fixed Maturity Securities	12 Months Ended
	Dec. 31, 2013
Debt Securities
Schedule of Marketable Securities [Line Items]
Investments In Fixed Maturity Securities	Investments in Fixed Maturity Securities At December 31, 2015 and 2014 , investments in fixed maturity securities were as follows: (In thousands) Amortized Gross Unrealized Fair Carrying Gains Losses December 31, 2015 Held to maturity: State and municipal $ 77,129 $ 16,246 $ — $ 93,375 $ 77,129 Residential mortgage-backed 19,138 2,207 — 21,345 19,138 Corporate — — — — — Total held to maturity 96,267 18,453 — 114,720 96,267 Available for sale: U.S. government and government agency 645,092 27,660 (2,333 ) 670,419 670,419 State and municipal: Special revenue 2,510,816 102,909 (3,737 ) 2,609,988 2,609,988 State general obligation 583,456 28,068 (2,070 ) 609,454 609,454 Pre-refunded 439,772 32,056 (31 ) 471,797 471,797 Corporate backed 388,904 14,039 (402 ) 402,541 402,541 Local general obligation 342,158 24,270 (29 ) 366,399 366,399 Total state and municipal 4,265,106 201,342 (6,269 ) 4,460,179 4,460,179 Mortgage-backed securities: Residential (1) 1,126,382 18,935 (11,180 ) 1,134,137 1,134,137 Commercial 64,975 875 (128 ) 65,722 65,722 Total mortgage-backed securities 1,191,357 19,810 (11,308 ) 1,199,859 1,199,859 Asset-backed securities 1,706,694 12,892 (14,414 ) 1,705,172 1,705,172 Corporate: Industrial 1,976,393 75,168 (30,027 ) 2,021,534 2,021,534 Financial 1,153,096 31,744 (11,819 ) 1,173,021 1,173,021 Utilities 192,857 8,321 (2,527 ) 198,651 198,651 Other 81,607 245 (20 ) 81,832 81,832 Total corporate 3,403,953 115,478 (44,393 ) 3,475,038 3,475,038 Foreign 799,839 50,310 (12,689 ) 837,460 837,460 Total available for sale 12,012,041 427,492 (91,406 ) 12,348,127 12,348,127 Total investments in fixed maturity securities $ 12,108,308 $ 445,945 $ (91,406 ) $ 12,462,847 $ 12,444,394 (In thousands) Amortized Gross Unrealized Fair Carrying Gains Losses December 31, 2014 Held to maturity: State and municipal $ 72,901 $ 17,501 $ — $ 90,402 $ 72,901 Residential mortgage-backed 23,278 2,854 — 26,132 23,278 Corporate 4,998 291 — 5,289 4,998 Total held to maturity 101,177 20,646 — 121,823 101,177 Available for sale: U.S. government and government agency 773,192 33,353 (3,157 ) 803,388 803,388 State and municipal: Special revenue 2,264,210 111,841 (2,084 ) 2,373,967 2,373,967 State general obligation 674,022 37,615 (787 ) 710,850 710,850 Pre-refunded 504,778 35,619 (289 ) 540,108 540,108 Corporate backed 413,234 18,976 (855 ) 431,355 431,355 Local general obligation 281,622 25,099 (5 ) 306,716 306,716 Total state and municipal 4,137,866 229,150 (4,020 ) 4,362,996 4,362,996 Mortgage-backed securities: Residential (1) 1,201,924 27,124 (9,449 ) 1,219,599 1,219,599 Commercial 74,479 1,610 (52 ) 76,037 76,037 Total mortgage-backed securities 1,276,403 28,734 (9,501 ) 1,295,636 1,295,636 Asset-backed securities 2,019,032 18,868 (11,974 ) 2,025,926 2,025,926 Corporate: Industrial 1,606,724 117,206 (5,131 ) 1,718,799 1,718,799 Financial 1,140,801 38,080 (7,673 ) 1,171,208 1,171,208 Utilities 184,107 12,436 (1 ) 196,542 196,542 Other 86,294 1,370 (2 ) 87,662 87,662 Total corporate 3,017,926 169,092 (12,807 ) 3,174,211 3,174,211 Foreign 897,668 62,223 (18,065 ) 941,826 941,826 Total available for sale 12,122,087 541,420 (59,524 ) 12,603,983 12,603,983 Total investments in fixed maturity securities $ 12,223,264 $ 562,066 $ (59,524 ) $ 12,725,806 $ 12,705,160 (1) Gross unrealized losses for mortgage-backed securities include $1,269,491 and $1,095,671 , as of December 31, 2015 and 2014 , respectively, related to the non-credit portion of OTTI recognized in other comprehensive income. The amortized cost and fair value of fixed maturity securities at December 31, 2015 , by contractual maturity, are shown below. Actual maturities may differ from contractual maturities because certain issuers may have the right to call or prepay obligations. (In thousands) Amortized Cost Fair Value Due in one year or less $ 711,642 $ 717,075 Due after one year through five years 4,056,450 4,185,436 Due after five years through ten years 3,653,308 3,795,614 Due after ten years 2,476,413 2,543,518 Mortgage-backed securities 1,210,495 1,221,204 Total $ 12,108,308 $ 12,462,847 At December 31, 2015 and 2014 , there were no investments, other than investments in United States government and government agency securities, which exceeded 10% of common stockholders’ equity. At December 31, 2015 , investments with a carrying value of $1,201 million were on deposit in custodial or trust accounts, of which $963 million was on deposit with state insurance departments, $182 million was on deposit in support of the Company’s underwriting activities at Lloyd’s, $41 million was on deposit as security for reinsurance clients and $15 million was on deposit as security for letters of credit issued in support of the Company’s reinsurance operations.

Investments In Equity Securitie

Investments In Equity Securities Available for Sale	12 Months Ended
	Dec. 31, 2015
Equity securities available for sale
Schedule of Available-for-sale Securities [Line Items]
Investments in Equity Securities	Investments in Equity Securities Available for Sale At December 31, 2015 and 2014 , investments in equity securities available for sale were as follows: (In thousands) Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Carrying Value December 31, 2015 Common stocks $ 56,462 $ — $ (19,189 ) $ 37,273 $ 37,273 Preferred stocks 108,730 8,216 (3,353 ) 113,593 113,593 Total $ 165,192 $ 8,216 $ (22,542 ) $ 150,866 $ 150,866 December 31, 2014 Common stocks $ 69,870 $ 11,929 $ (5,453 ) $ 76,346 $ 76,346 Preferred stocks 90,425 8,385 (4,165 ) 94,645 94,645 Total $ 160,295 $ 20,314 $ (9,618 ) $ 170,991 $ 170,991

Arbitrage Trading Account

Arbitrage Trading Account	12 Months Ended
	Dec. 31, 2015
Trading Securities and Derivative Instruments [Abstract]
Arbitrage Trading Account	Arbitrage Trading Account At December 31, 2015 and 2014 , the fair value and carrying value of the arbitrage trading account were $377 million and $451 million , respectively. The primary focus of the trading account is merger arbitrage. Merger arbitrage is the business of investing in the securities of publicly held companies which are the targets in announced tender offers and mergers. Arbitrage investing differs from other types of investing in its focus on transactions and events believed likely to bring about a change in value over a relatively short time period (usually four months or less). The Company uses put options, call options and swap contracts in order to mitigate the impact of potential changes in market conditions on the merger arbitrage trading account. These options and contracts are reported at fair value. As of December 31, 2015 , the fair value of long option contracts outstanding was $3 million (notional amount of $52 million ) and the fair value of short option contracts outstanding was $1 million (notional amount of $62 million ). Other than with respect to the use of these trading account securities, the Company does not make use of derivatives.

Net Investment Income

Net Investment Income	12 Months Ended
	Dec. 31, 2015
Net Investment Income [Abstract]
Net Investment Income	Net Investment Income Net investment income consists of the following: (In thousands) 2015 2014 2013 Investment income earned on: Fixed maturity securities, including cash and cash equivalents and loans receivable $ 428,325 $ 439,489 $ 442,287 Equity securities available for sale 4,624 6,726 11,380 Investment funds 62,228 131,649 67,712 Arbitrage trading account 16,891 22,438 20,431 Real estate 11,294 10,228 12,498 Gross investment income 523,362 610,530 554,308 Investment expense (10,717 ) (9,645 ) (10,017 ) Net investment income $ 512,645 $ 600,885 $ 544,291

Investment Funds

Investment Funds	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Investment Funds	Investment Funds Investment funds consist of the following: Carrying Value as of December 31, Income (Losses) (In thousands) 2015 2014 2015 2014 2013 Real estate $ 580,830 $ 466,703 $ 58,032 $ 26,233 $ 9,315 Energy 93,719 152,056 (37,373 ) 12,797 29,739 Hedged equity 70,580 282,335 (2,762 ) 10,760 7,655 Other funds 424,911 310,307 44,331 81,859 21,003 Total $ 1,170,040 $ 1,211,401 $ 62,228 $ 131,649 $ 67,712 Other funds include private equity investments carried on the equity method of accounting, which includes a publicly traded common stock investment in HealthEquity, Inc. (HQY). Our ownership interest in HQY as of December 31, 2015 is approximately 21% with a fair value of $300.1 million and a carrying value of $45.4 million .

Real Estate (Notes)

Real Estate (Notes)	12 Months Ended
	Dec. 31, 2015
Real Estate [Abstract]
Real Estate	Real Estate Investment in real estate represents directly owned property held for investment, as follows: As of December 31, (In thousands) 2015 2014 Properties in operation $ 226,055 $ 196,980 Properties under development 710,312 534,632 Total $ 936,367 $ 731,612 In 2015, properties in operation included a long-term ground lease in Washington, D.C. and office buildings in West Palm Beach and Palm Beach, Florida. Properties in operation are net of accumulated depreciation and amortization of $9,073,000 and $1,609,000 as of December 31, 2015 and 2014 , respectively. Related depreciation expense was $7,425,000 and $4,808,000 for the years ended December 31, 2015 and 2014 , respectively. Future minimum rental income expected on operating leases relating to properties in operation is $13,141,756 in 2016 , $15,483,248 in 2017 , $14,623,307 in 2018 , $11,967,190 in 2019 , $9,584,128 in 2020 and $352,328,662 thereafter. Properties under development represent the following: an office building in London, a mixed-use project in Washington D.C. and an office complex in New York City.

Loans Receivable

Loans Receivable	12 Months Ended
	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Loans Receivable	Loans Receivable Loans receivable are as follows: As of December 31, (In thousands) 2015 2014 Amortized cost: Real estate loans $ 200,499 $ 243,407 Commercial loans 72,604 78,605 Total $ 273,103 $ 322,012 Fair value: Real estate loans $ 201,641 $ 245,112 Commercial loans 74,106 80,107 Total $ 275,747 $ 325,219 Valuation allowance: Specific $ — $ 115 General 2,094 2,371 Total $ 2,094 $ 2,486 For the Year Ended December 31, 2015 2014 (Decrease) increase in valuation allowance $ (392 ) $ 398 Loans receivable in non-accrual status were $3.1 million and $14.2 million as of December 31, 2015 and 2014 , respectively, primarily resulting from the sale of such loans. The Company monitors the performance of its loans receivable and assesses the ability of the borrower to pay principal and interest based upon loan structure, underlying property values, cash flow and related financial and operating performance of the property and market conditions. Loans receivable with a potential for default are further assessed using discounted cash flow analysis and comparable cost and sales methodologies, if appropriate. The real estate loans are secured by commercial real estate primarily located in Arizona, Maryland, New York and Tennessee. These loans generally earn interest at floating LIBOR-based interest rates and have maturities (inclusive of extension options) through August 2025. The commercial loans are with small business owners who have secured the related financing with the assets of the business. These loans generally earn interest on a fixed basis and have varying maturities not exceeding 10 years. The Company utilizes a risk rating system to assign a risk to each of its real estate loans. The loan rating system takes into consideration credit quality indicators including loan to value ratios, which compare the outstanding loan amount to the estimated value of the property, the borrower’s financial condition and performance with respect to loan terms, the Company’s position in the capital structure, and the overall leverage in the capital structure. Based on this rating system, none of the real estate loans were considered to be impaired at December 31, 2015 , and accordingly, the Company determined that a specific valuation allowance was not required.

Realized And Unrealized Investm

Realized And Unrealized Investment Gains and Losses	12 Months Ended
	Dec. 31, 2015
Realized and Unrealized Investment Gains (Losses) [Abstract]
Realized and Unrealized Investment Gains and Losses	Realized and Unrealized Investment Gains and Losses Realized and unrealized investment gains and losses are as follows: (In thousands) 2015 2014 2013 Realized investment gains and losses: Fixed maturity securities: Gains $ 23,755 $ 39,113 $ 48,860 Losses (4,065 ) (4,420 ) (14,670 ) Equity securities available for sale 9,639 38,296 70,235 Investment funds 93,529 96,204 10,976 Real estate — 85,659 — Other gains 2,775 — 12,185 Net realized gains on investments sales 125,633 254,852 127,586 Net other-than-temporary impairments: Other-than-temporary impairments (33,309 ) — (6,042 ) Net other-than-temporary impairments (33,309 ) — (6,042 ) Total net investment gains 92,324 254,852 121,544 Income tax expense (32,313 ) (89,198 ) (47,426 ) After-tax realized investment gain and losses $ 60,011 $ 165,654 $ 74,118 Change in unrealized gains and losses of available for sales securities: Fixed maturity securities $ (144,445 ) $ 155,765 $ (401,812 ) Previously impaired fixed maturity securities (174 ) 865 1,076 Equity securities available for sale (27,809 ) (69,016 ) 11,864 Investment funds (19,758 ) (14,725 ) (10,250 ) Total change in unrealized gains (192,186 ) 72,889 (399,122 ) Income tax benefit (expense) 66,644 (23,223 ) 138,058 Noncontrolling interests 38 (33 ) (28 ) After-tax change in unrealized investment gain and losses of available for sale securities $ (125,504 ) $ 49,633 $ (261,092 ) OTTI recognized in earnings were $33.3 million and $6 million for the years ended December 31, 2015 and December 31, 2013 , respectively. There were no OTTI for the year ended December 31, 2014 . For the year ended December 31, 2015 , OTTI related to equity securities were $24.3 million and related to fixed maturity securities were $9 million . For the year ended December 31, 2013 , OTTI related to equity securities. Realized and Unrealized Investment Gains and Losses Realized and unrealized investment gains and losses are as follows: (In thousands) 2015 2014 2013 Realized investment gains and losses: Fixed maturity securities: Gains $ 23,755 $ 39,113 $ 48,860 Losses (4,065 ) (4,420 ) (14,670 ) Equity securities available for sale 9,639 38,296 70,235 Investment funds 93,529 96,204 10,976 Real estate — 85,659 — Other gains 2,775 — 12,185 Net realized gains on investments sales 125,633 254,852 127,586 Net other-than-temporary impairments: Other-than-temporary impairments (33,309 ) — (6,042 ) Net other-than-temporary impairments (33,309 ) — (6,042 ) Total net investment gains 92,324 254,852 121,544 Income tax expense (32,313 ) (89,198 ) (47,426 ) After-tax realized investment gain and losses $ 60,011 $ 165,654 $ 74,118 Change in unrealized gains and losses of available for sales securities: Fixed maturity securities $ (144,445 ) $ 155,765 $ (401,812 ) Previously impaired fixed maturity securities (174 ) 865 1,076 Equity securities available for sale (27,809 ) (69,016 ) 11,864 Investment funds (19,758 ) (14,725 ) (10,250 ) Total change in unrealized gains (192,186 ) 72,889 (399,122 ) Income tax benefit (expense) 66,644 (23,223 ) 138,058 Noncontrolling interests 38 (33 ) (28 ) After-tax change in unrealized investment gain and losses of available for sale securities $ (125,504 ) $ 49,633 $ (261,092 )

Securities In An Unrealized Los

Securities In An Unrealized Loss Position	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Securities In An Unrealized Loss Position	Securities in an Unrealized Loss Position The following table summarizes all securities in an unrealized loss position at December 31, 2015 and 2014 by the length of time those securities have been continuously in an unrealized loss position. Less Than 12 Months 12 Months or Greater Total (In thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses December 31, 2015 U.S. government and government agency $ 101,660 $ 487 $ 64,500 $ 1,846 $ 166,160 $ 2,333 State and municipal 501,952 4,404 106,681 1,865 608,633 6,269 Mortgage-backed securities 381,986 3,639 184,807 7,669 566,793 11,308 Asset-backed securities 1,091,078 7,703 190,467 6,711 1,281,545 14,414 Corporate 1,232,940 35,406 76,797 8,987 1,309,737 44,393 Foreign government 169,190 8,822 19,528 3,867 188,718 12,689 Fixed maturity securities 3,478,806 60,461 642,780 30,945 4,121,586 91,406 Common stocks 18,641 18,005 7,829 1,184 26,470 19,189 Preferred stocks — — 22,320 3,353 22,320 3,353 Equity securities available for sale 18,641 18,005 30,149 4,537 48,790 22,542 Total $ 3,497,447 $ 78,466 $ 672,929 $ 35,482 $ 4,170,376 $ 113,948 December 31, 2014 U.S. government and government agency $ 84,750 $ 522 $ 84,850 $ 2,635 $ 169,600 $ 3,157 State and municipal 158,594 631 150,284 3,389 308,878 4,020 Mortgage-backed securities 75,739 332 312,922 9,169 388,661 9,501 Asset-backed securities 1,186,097 6,217 30,818 5,757 1,216,915 11,974 Corporate 400,141 2,480 183,810 10,327 583,951 12,807 Foreign government 76,471 3,907 85,025 14,158 161,496 18,065 Fixed maturity securities 1,981,792 14,089 847,709 45,435 2,829,501 59,524 Common stocks 15,929 5,453 — — 15,929 5,453 Preferred stocks 27,126 1,139 22,648 3,026 49,774 4,165 Equity securities available for sale 43,055 6,592 22,648 3,026 65,703 9,618 Total $ 2,024,847 $ 20,681 $ 870,357 $ 48,461 $ 2,895,204 $ 69,142 Fixed Maturity Securities — A summary of the Company’s non-investment grade fixed maturity securities that were in an unrealized loss position at December 31, 2015 is presented in the table below: (Dollars in thousands) Number of Securities Aggregate Fair Value Gross Unrealized Loss Mortgage-backed securities 8 $ 23,370 $ 1,790 Asset-backed securities 7 19,535 264 Corporate 12 128,716 6,717 Foreign government 1 13,956 3,766 Total 28 $ 185,577 $ 12,537 For OTTI of fixed maturity securities that management does not intend to sell or, more likely than not, would not be required to sell, the portion of the decline in value considered to be due to credit factors is recognized in earnings and the portion of the decline in value considered to be due to non-credit factors is recognized in other comprehensive income. For the year ended December 31, 2015 , OTTI for fixed maturities recognized in earnings were $9.0 million , all of which was considered due to credit factors. There were no OTTI of fixed maturity securities for the year ended December 31, 2014 . The Company has evaluated its fixed maturity securities in an unrealized loss position and believes the unrealized losses are due primarily to temporary market and sector-related factors rather than to issuer-specific factors. None of these securities are delinquent or in default on financial covenants. Based on its assessment of these issuers, the Company expects them to continue to meet their contractual payment obligations as they become due and does not consider any of these securities to be OTTI. Preferred Stocks – At December 31, 2015 , there was one preferred stock in an unrealized loss position, with an aggregate fair value of $22.3 million and a gross unrealized loss of $3.4 million . The preferred stock is rated investment grade. Management believes the unrealized loss is due primarily to market and sector related factors and does not consider it to be OTTI. For the year ended December 31, 2015 , OTTI for preferred stocks were $13.4 million . There were no OTTI of preferred stocks for the year ended December 31, 2014 . Common Stocks – At December 31, 2015 , there were two common stocks in an unrealized loss position, with an aggregate fair value of $26.5 million and a gross unrealized loss of $19.2 million . Based on management's view on the underlying securities, the Company does not consider the common stocks to be OTTI. For the year ended December 31, 2015 , OTTI for common stocks were $10.9 million . There were no OTTI of common stocks for the year ended December 31, 2014 . Loans Receivable – The Company monitors the performance of its loans receivable, including current market conditions for each loan and the ability to collect principal and interest. For loans where the Company determines it is probable that the contractual terms will not be met, an analysis is performed and a valuation reserve is established, if necessary, with a charge to earnings. Loans receivable are reported net of a valuation reserve of $2 million and $3 million at December 31, 2015 and 2014 , respectively.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company’s fixed maturity and equity securities classified as available for sale and its trading account securities are carried at fair value. Fair value is defined as “the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.” The Company utilizes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels, as follows: Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 - Quoted prices for similar assets or valuations based on inputs that are observable. Level 3 - Estimates of fair value based on internal pricing methodologies using unobservable inputs. Unobservable inputs are only used to measure fair value to the extent that observable inputs are not available. Substantially all of the Company’s fixed maturity securities were priced by independent pricing services. The prices provided by the independent pricing services are estimated based on observable market data in active markets utilizing pricing models and processes, which may include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, sector groupings, matrix pricing and reference data. The pricing services may prioritize inputs differently on any given day for any security based on market conditions, and not all inputs are available for each security evaluation on any given day. The pricing services used by the Company have indicated that they will only produce an estimate of fair value if objectively verifiable information is available. The determination of whether markets are active or inactive is based upon the volume and level of activity for a particular asset class. The Company reviews the prices provided by pricing services for reasonableness and periodically performs independent price tests of a sample of securities to ensure proper valuation. If prices from independent pricing services are not available for fixed maturity securities, the Company estimates the fair value. For Level 2 securities, the Company utilizes pricing models and processes which may include benchmark yields, sector groupings, matrix pricing, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, bids, offers and reference data. Where broker quotes are used, the Company generally requests two or more quotes and sets a price within the range of quotes received based on its assessment of the credibility of the quote and its own evaluation of the security. The Company generally does not adjust quotes received from brokers. For securities traded only in private negotiations, the Company determines fair value based primarily on the cost of such securities, which is adjusted to reflect prices of recent placements of securities of the same issuer, financial projections, credit quality and business developments of the issuer and other relevant information. For Level 3 securities, the Company generally uses a discounted cash flow model to estimate the fair value of fixed maturity securities. The cash flow models are based upon assumptions as to prevailing credit spreads, interest rate and interest rate volatility, time to maturity and subordination levels. Projected cash flows are discounted at rates that are adjusted to reflect illiquidity, where appropriate. The following tables present the assets and liabilities measured at fair value on a recurring basis as of December 31, 2015 and 2014 by level: (In thousands) Total Level 1 Level 2 Level 3 December 31, 2015 Assets: Fixed maturity securities available for sale: U.S. government and government agency $ 670,419 $ — $ 670,419 $ — State and municipal 4,460,179 — 4,460,179 — Mortgage-backed securities 1,199,859 — 1,199,859 — Asset-backed securities 1,705,172 — 1,704,973 199 Corporate 3,475,038 — 3,474,884 154 Foreign government 837,460 — 837,460 — Total fixed maturity securities available for sale 12,348,127 — 12,347,774 353 Equity securities available for sale: Common stocks 37,273 29,444 — 7,829 Preferred stocks 113,593 — 109,969 3,624 Total equity securities available for sale 150,866 29,444 109,969 11,453 Arbitrage trading account 376,697 256,914 119,607 176 Total $ 12,875,690 $ 286,358 $ 12,577,350 $ 11,982 Liabilities: Trading account securities sold but not yet purchased $ 37,035 $ 35,559 $ 1,476 $ — December 31, 2014 Assets: Fixed maturity securities available for sale: U.S. government and government agency $ 803,388 $ — $ 803,388 $ — State and municipal 4,362,996 — 4,362,996 — Mortgage-backed securities 1,295,636 — 1,295,636 — Asset-backed securities 2,025,926 — 2,005,315 20,611 Corporate 3,174,211 — 3,174,057 154 Foreign government 941,826 — 941,826 — Total fixed maturity securities available for sale 12,603,983 — 12,583,218 20,765 Equity securities available for sale: Common stocks 76,346 65,605 — 10,741 Preferred stocks 94,645 — 90,932 3,713 Total equity securities available for sale 170,991 65,605 90,932 14,454 Arbitrage trading account 450,648 295,047 154,881 720 Total $ 13,225,622 $ 360,652 $ 12,829,031 $ 35,939 Liabilities: Trading account securities sold but not yet purchased $ 106,079 $ 106,074 $ 5 $ — There were no significant transfers between Levels 1 and 2 for the years ended December 31, 2015 and 2014 . The following tables summarize changes in Level 3 assets and liabilities for the years ended December 31, 2015 and 2014 : Gains (Losses) Included in: (In thousands) Beginning Balance Earnings (Losses) Other Comprehensive Income (Losses) Impairments Purchases Sales Paydowns/Maturities Transfers In / Out Ending Balance Year ended December 31, 2015 Assets: Fixed maturity securities available for sale: Asset-backed securities $ 20,611 $ 19 $ 191 $ — $ — $ — $ (1,820 ) $ (18,802 ) $ 199 Corporate 154 — — — — — — — 154 Total 20,765 19 191 — — — (1,820 ) (18,802 ) 353 Equity securities available for sale: Common stocks 10,741 — (273 ) (2,331 ) — (308 ) — — 7,829 Preferred stocks 3,713 (89 ) — — — — — — 3,624 Total 14,454 (89 ) (273 ) (2,331 ) — (308 ) — — 11,453 Arbitrage trading account 720 (799 ) — — 72,640 (71,921 ) — (464 ) 176 Total $ 35,939 $ (869 ) $ (82 ) $ (2,331 ) $ 72,640 $ (72,229 ) $ (1,820 ) $ (19,266 ) $ 11,982 Liabilities: Trading account securities sold but not yet purchased $ — $ — $ — $ — $ — $ — $ — $ — $ — Year ended December 31, 2014 Assets: Fixed maturity securities available for sale: Asset-backed securities $ 42,710 $ 47 $ (3,711 ) $ — $ 238 $ (15,244 ) $ (3,429 ) $ — $ 20,611 Corporate $ 154 $ — $ — $ — $ — $ — $ — $ — $ 154 Total 42,864 47 (3,711 ) — 238 (15,244 ) (3,429 ) — 20,765 Equity securities available for sale: Common stocks 1,238 — (911 ) — 11,343 (929 ) — — 10,741 Preferred stocks 3,752 (17 ) — — 3,430 (3,452 ) — — 3,713 Total 4,990 (17 ) (911 ) — 14,773 (4,381 ) — — 14,454 Arbitrage trading account 1,780 2,274 — — 4,942 (14,073 ) — 5,797 720 Total $ 49,634 $ 2,304 $ (4,622 ) $ — $ 19,953 $ (33,698 ) $ (3,429 ) $ 5,797 $ 35,939 Liabilities: Trading account securities sold but not yet purchased $ — $ (20 ) $ — $ — $ 31 $ (11 ) $ — $ — $ — During the year ended December 31, 2015 , five securities were transferred out of Level 3 as an observable price was available. During the year ended December 31, 2014 , two securities were transferred into Level 3 as quoted prices were no longer available. Fair Value of Financial Instruments The following table presents the carrying amounts and estimated fair values of the Company’s financial instruments as of December 31, 2015 and 2014 : 2015 2014 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Assets: Fixed maturity securities $ 12,444,394 $ 12,462,847 $ 12,705,160 $ 12,725,806 Equity securities available for sale 150,866 150,866 170,991 170,991 Arbitrage trading account 376,697 376,697 450,648 450,648 Loans receivable 273,103 275,747 322,012 325,219 Cash and cash equivalents 763,631 763,631 674,441 674,441 Trading accounts receivable from brokers and clearing organizations 383,115 383,115 371,034 371,034 Due from broker 1,713 1,713 — — Liabilities: Due to broker — — 23,133 23,133 Trading account securities sold but not yet purchased 37,035 37,035 106,079 106,079 Subordinated debentures 340,320 355,880 340,060 332,640 Senior notes and other debt 1,844,621 2,029,572 2,115,527 2,344,292 The estimated fair values of the Company’s fixed maturity securities, equity securities available for sale and arbitrage trading account securities are based on various valuation techniques that rely on fair value measurements as described in Note 13 above. The fair value of loans receivable are estimated by using current institutional purchaser yield requirements for loans with similar credit characteristics, which is considered a Level 2 input. The fair value of the senior notes and other debt and the subordinated debentures is based on spreads for similar securities, which is considered a Level 2 input.

Reserves For Losses And Loss Ex

Reserves For Losses And Loss Expenses	12 Months Ended
	Dec. 31, 2014
Insurance [Abstract]
Reserves For Losses And Loss Expenses	Reserves for Losses and Loss Expenses The table below provides a reconciliation of the beginning and ending reserve balances: (In thousands) 2015 2014 2013 Net reserves at beginning of year $ 8,970,641 $ 8,683,797 $ 8,411,851 Net provision for losses and loss expenses: Claims occuring during the current year(1) 3,653,561 3,495,825 3,221,393 Decrease in estimates for claims occurring in prior years(2)(3) (46,713 ) (75,764 ) (78,810 ) Loss reserve discount accretion(4) 49,422 70,506 54,441 Total 3,656,270 3,490,567 3,197,024 Net payments for claims: Current year 914,637 898,944 822,787 Prior year 2,342,378 2,216,283 2,055,284 Total 3,257,015 3,115,227 2,878,071 Foreign currency translation (125,024 ) (88,496 ) (47,007 ) Net reserves at end of year 9,244,872 8,970,641 8,683,797 Ceded reserve at end of year 1,424,278 1,399,060 1,397,144 Gross reserves at end of year $ 10,669,150 $ 10,369,701 $ 10,080,941 _______________________________________ (1) Claims occurring during the current year are net of loss reserve discounts of $20,357,000 , $21,306,000 , and $22,680,000 in 2015 , 2014 and 2013 , respectively. (2) The decrease in estimates for claims occurring in prior years is net of loss reserve discount. On an undiscounted basis, the estimates for claims occurring in prior years decreased by $64,971,000 , $116,866,000 and $77,430,000 in 2015 , 2014 and 2013 , respectively. (3) For certain retrospectively rated insurance polices and reinsurance agreements, reserve development is offset by additional or return premiums. Favorable reserve development, net of additional and return premiums, was $63 million , $85 million and $98 million in 2015 , 2014 and 2013 , respectively. (4) In 2014, the Company entered into a commutation agreement that resulted in a reduction in prior year workers' compensation reserves of $ 30 million on an undiscounted basis and $12 million on a discounted basis. Favorable prior year development (net of additional and return premiums) was $63 million in 2015. Insurance-Domestic - Reserves for the Insurance-Domestic segment developed favorably by $47 million in 2015. The favorable development was primarily related to workers' compensation and other liability business, and was partially offset by unfavorable development for commercial automobile liability business. For workers' compensation, the favorable development was related to both primary and excess business and to many accident years, including those prior to 2006. In 2015, reported workers' compensation losses were below our expectations for many of our operating units. In addition, overall loss frequency and severity trends emerged better than the assumptions underlying our previous reserve estimates. The long term trend of declining workers' compensation claim frequency continued in 2015. The improvement is attributable to better workplace safety and to benign medical severity trends as we continue to invest in medical case management services and higher usage of preferred provider networks. For other liability business, favorable development was concentrated in accident years 2007 through 2013. The favorable development was primarily related to our excess and surplus lines casualty business that has benefited from a persistent improvement in claim frequency trends over the past several years. For commercial automobile business, adverse development was primarily related to large losses for long-haul trucking business and to accident years 2011 through 2014. The higher loss cost trends for the commercial automobile industry are attributable, in part, to the increase in miles driven as the economy has improved and fuel prices have declined over the past several years. Reinsurance-Global - Reserves for the Reinsurance-Global segment developed favorably by $11 million in 2015. The favorable development was primarily related to direct facultative reinsurance business and to accident years 2005 through 2013. Loss reserves developed favorably for umbrella business and for other liability coverage for contractors. Insurance-International - Reserves for the Insurance-International segment developed favorably by $5 million in 2015. The favorable development was related primarily to commercial property. The favorable commercial property development was attributable to accident years 2012 through 2014 and was driven by favorable frequency and severity trends on property business written in Lloyd's. The favorable property development was partially offset by unfavorable development for professional indemnity business in the U.K., primarily for accident years 2006 through 2013. Favorable prior year development (net of additional and return premiums) was $85 million in 2014. For the Insurance-Domestic segment, favorable development in 2014 of $ 92 million was driven primarily by other liability business for accident years 2006 through 2010, primarily related to our excess and surplus lines casualty business. Reported losses during these years continued to be below our initial expectations at the time the business was written, largely as a result of persistent improvement in claim frequency trends (i.e., number of reported claims per unit of exposure). As these accident years have matured, the weighting of actuarial methods has shifted from methods based on initial expected losses to methods based on actual reported losses. We believe the favorable claim frequency trends we have seen during this time period are due to changes in the mix of business written and to the general slowdown in the economy. Commercial automobile reported unfavorable development primarily as a result of large losses for long-haul trucking business in 2012 and 2013. For the Reinsurance-Global segment, favorable reserve development in 2014 of $16 million was driven primarily by assumed professional liability excess of loss and umbrella treaty business, as well as direct facultative business. This was partially offset by adverse development on brokerage facultative business caused by completed operations losses associated with construction projects in accident years prior to 2009. For the Insurance-International segment, adverse reserve development in 2014 of $23 million was driven primarily by unexpected large losses from accident years 2009-2012 in the professional indemnity line of business in the United Kingdom. Favorable prior year reserve development (net of additional and return premiums) was $98 million in 2013. Favorable development in 2013 was primarily attributable to accident years 2006 through 2012 and included favorable development of $39 million for other liability business, $32 million for reinsurance assumed liability business, $22 million for workers’ compensation, $18 million for commercial property and $24 million for other lines of business. The favorable development in 2013 was largely driven by loss cost trends, which were more favorable than originally anticipated. In particular, loss frequency trends have been more favorable than expected for excess & surplus lines casualty business, workers' compensation and excess of loss professional and other liability business. The 2013 favorable development was partially offset by unfavorable development of $23 million for commercial automobile business and $14 million for products liability business. Commercial automobile development was driven by large losses for long-haul trucking business in 2011 and 2012. Product liability development stemmed from completed operations losses associated with construction projects in accident years prior to 2009. Environmental and Asbestos — To date, known environmental and asbestos claims have not had a material impact on the Company’s operations, because its subsidiaries generally did not insure large industrial companies that are subject to significant environmental or asbestos exposures prior to 1986 when an absolute exclusion was incorporated into standard policy language. The Company’s net reserves for losses and loss expenses relating to asbestos and environmental claims was $33 million at December 31, 2015 and $36 million at December 31, 2014 . The Company’s gross reserves for losses and loss expenses relating to asbestos and environmental claims were $51 million and $56 million at December 31, 2015 and 2014 , respectively. Net incurred losses and loss expenses for reported asbestos and environmental claims decreased approximately $2 million in 2015 and increased by approximately $4 million and $5 million in 2014 and 2013 , respectively. Net paid losses and loss expenses for asbestos and environmental claims were approximately $2 million in 2015 , $3 million in 2014 and $3 million in 2013 . The estimation of these liabilities is subject to significantly greater than normal variation and uncertainty because it is difficult to make an actuarial estimate of these liabilities due to the absence of a generally accepted actuarial methodology for these exposures and the potential effect of significant unresolved legal matters, including coverage issues, as well as the cost of litigating the legal issues. Additionally, the determination of ultimate damages and the final allocation of such damages to financially responsible parties are highly uncertain. Discounting — The Company discounts its liabilities for certain workers’ compensation reserves. The amount of workers’ compensation reserves that were discounted was $2,308 million and $2,187 million at December 31, 2015 and December 31, 2014 , respectively. The aggregate net discount for those reserves, after reflecting the effects of ceded reinsurance, was $699 million and $746 million at December 31, 2015 and December 31, 2014 , respectively. At December 31, 2015 , discount rates by year ranged from 2.0% to 6.5%, with a weighted average discount rate of 3.9%. Substantially all of discounted workers’ compensation reserves (98% of total discounted reserves at December 31, 2015 ) are excess workers’ compensation reserves. In order to properly match loss expenses with income earned on investment securities supporting the liabilities, reserves for excess workers’ compensation business are discounted using risk-free discount rates determined by reference to the U.S. Treasury yield curve. These rates are determined annually based on the weighted average rate for the period. Once established, no adjustments are made to the discount rate for that period, and any increases or decreases in loss reserves in subsequent years are discounted at the same rate, without regard to when any such adjustments are recognized. The expected loss and loss expense payout patterns subject to discounting are derived from the Company’s loss payout experience. The Company also discounts reserves for certain other long-duration workers’ compensation reserves (representing approximately 2% of total discounted reserves at December 31, 2015 ), including reserves for quota share reinsurance and reserves related to losses regarding occupational lung disease. These reserves are discounted at statutory rates permitted by the Department of Insurance of the State of Delaware.

Reinsurance

Reinsurance	12 Months Ended
	Dec. 31, 2015
Reinsurance Disclosures [Abstract]
Reinsurance	Reinsurance The Company reinsures a portion of its insurance exposures in order to reduce its net liability on individual risks and catastrophe losses. Reinsurance coverage and retentions vary depending on the line of business, location of the risk and nature of loss. The Company’s reinsurance purchases include the following: property reinsurance treaties that reduce exposure to large individual property losses and catastrophe events; casualty reinsurance treaties that reduce its exposure to large individual casualty losses, workers’ compensation catastrophe losses and casualty losses involving multiple claimants or insureds; and facultative reinsurance that reduces exposure on individual policies or risks for losses that exceed treaty reinsurance capacity. Depending on the operating unit, the Company purchases specific additional reinsurance to supplement the above programs. The following is a summary of reinsurance financial information: (In thousands) 2015 2014 2013 Written premiums: Direct $ 6,412,533 $ 6,185,242 $ 5,626,172 Assumed 837,460 877,596 884,919 Ceded (1,060,478 ) (1,065,891 ) (1,010,918 ) Total net written premiums $ 6,189,515 $ 5,996,947 $ 5,500,173 Earned premiums: Direct $ 6,245,714 $ 5,889,021 $ 5,328,955 Assumed 845,735 886,063 857,119 Ceded (1,050,840 ) (1,030,666 ) (959,537 ) Total net earned premiums $ 6,040,609 $ 5,744,418 $ 5,226,537 Ceded losses and loss expenses incurred $ 501,999 $ 475,802 $ 556,108 Ceded commission earned $ 129,766 $ 160,215 $ 137,449 The Company reinsures a portion of its exposures principally to reduce its net liability on individual risks and to protect against catastrophic losses. Estimated amounts due from reinsurers are reported net of reserves for uncollectible reinsurance of $1,020,000 , $1,144,000 and $1,385,000 as of December 31, 2015 , 2014 and 2013 , respectively. The following table presents the amounts due from reinsurers as of December 31, 2015 : (In thousands) Allegany Group $ 138,163 Munich Re 121,661 Swiss Re 115,215 Lloyd’s of London 92,635 Axis Capital 69,840 Partner Re 65,793 Hannover Re Group 48,675 Everest Re 47,945 Berkshire Hathaway 47,309 Chubb Limited (1) 45,645 Arch Capital Group 23,273 Other reinsurers less than $20,000 213,169 Subtotal 1,029,323 Residual market pools 503,506 Total $ 1,532,829 (1) Includes the aggregate recoverables from Ace Group and Chubb Group.

Indebtedness

Indebtedness	12 Months Ended
	Dec. 31, 2014
Senior Notes and Other Debt
Debt Instrument [Line Items]
Senior Notes And Other Debt	Indebtedness Indebtedness consisted of the following as of December 31, 2015 (the difference between the face value and the carrying value is unamortized discount): (In thousands) Interest Rate Face Value 2015 Carrying Value 2014 Carrying Value Senior notes due on: May 15, 2015 5.6% $ — $ — $ 199,930 August 15, 2019 6.15% 150,000 149,484 149,342 September 15, 2019 7.375% 300,000 299,054 298,800 September 15, 2020 5.375% 300,000 298,411 298,074 January 1, 2022 8.7% 76,503 76,097 76,048 March 15, 2022 4.625% 350,000 347,417 346,999 February 15, 2037 6.25% 250,000 247,676 247,566 August 1, 2044 4.75% 350,000 344,730 344,545 Subsidiary debt (1) Various 81,752 81,752 154,223 Total senior notes and other debt $ 1,858,255 $ 1,844,621 $ 2,115,527 Subordinated debentures, due on April, 30, 2053 5.625% $ 350,000 $ 340,320 $ 340,060 _____________ (1) Subsidiary debt is due as follows: $43 million in 2016 , $37 million in 2017 and $2 million thereafter.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense consists of: (In thousands) Current Expense Deferred Expense Total December 31, 2015 Domestic $ 179,150 $ 31,145 $ 210,295 Foreign (2,318 ) 19,946 17,628 Total expense $ 176,832 $ 51,091 $ 227,923 December 31, 2014 Domestic $ 258,337 $ 28,029 $ 286,366 Foreign 12,969 3,258 16,227 Total expense $ 271,306 $ 31,287 $ 302,593 December 31, 2013 Domestic $ 116,802 $ 47,370 $ 164,172 Foreign 22,362 7,053 29,415 Total expense $ 139,164 $ 54,423 $ 193,587 Income before income taxes from domestic operations was $689 million , $910 million and $598 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Income before income taxes from foreign operations was $43 million , $42 million and $101 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. A reconciliation of the income tax expense and the amounts computed by applying the Federal and foreign income tax rate of 35% to pre-tax income are as follows: (In thousands) 2015 2014 2013 Computed “expected” tax expense $ 256,210 $ 333,269 $ 244,611 Tax-exempt investment income (39,283 ) (38,757 ) (40,679 ) Change in valuation allowance 2,702 1,335 — Impact of foreign tax rates 4,447 6,239 (4,851 ) State and local taxes 940 2,375 2,906 Other, net 2,907 (1,868 ) (8,400 ) Total expense $ 227,923 $ 302,593 $ 193,587 At December 31, 2015 and 2014 , the tax effects of differences that give rise to significant portions of the deferred tax asset and deferred tax liability are as follows: (In thousands) 2015 2014 Deferred tax asset: Loss reserve discounting $ 100,806 $ 77,216 Unearned premiums 176,465 165,075 Other-than-temporary impairments 26,509 45,367 Restricted stock units 62,442 60,061 Other 89,761 101,131 Gross deferred tax asset 455,983 448,850 Less valuation allowance (4,037 ) (1,335 ) Deferred tax asset 451,946 447,515 Deferred tax liability: Amortization of intangibles 20,316 22,747 Deferred policy acquisition costs 162,344 152,001 Unrealized investment gains 115,499 175,111 Other 160,598 135,108 Deferred tax liability 458,757 484,967 Net deferred tax asset (liability) $ (6,811 ) $ (37,452 ) The Company had current tax receivables of $55,763,000 and $67,623,000 at December 31, 2015 and 2014 , respectively. At December 31, 2015 , the Company had foreign net operating loss carryforwards $6.1 million that expire beginning in 2031, and an additional $43.2 million that have no expiration date. At December 31, 2015 , the Company had a valuation allowance of $4.0 million , as compared to $1.3 million at December 31, 2014 . The Company has provided a valuation allowance against future tax benefits of certain foreign operations. The statute of limitations has closed for the Company’s tax returns through December 31, 2011 . The realization of the deferred tax asset is dependent upon the Company’s ability to generate sufficient taxable income in future periods. Based on historical results and the prospects for future current operations, management anticipates that it is more likely than not that future taxable income will be sufficient for the realization of this asset.

Dividends From Subsidiaries And

Dividends From Subsidiaries And Statutory Financial Information	12 Months Ended
	Dec. 31, 2015
Insurance [Abstract]
Dividends From Subsidiaries And Statutory Financial Information (Unaudited)	Dividends from Subsidiaries and Statutory Financial Information The Company’s insurance subsidiaries are restricted by law as to the amount of dividends they may pay without the approval of regulatory authorities. The Company’s lead insurer, Berkley Insurance Company (BIC), directly or indirectly owns all of the Company’s other insurance companies. During 2016 , the maximum amount of dividends that can be paid by BIC without such approval is approximately $684 million . BIC’s combined net income and statutory capital and surplus, as determined in accordance with statutory accounting practices (SAP), are as follows: (In thousands) 2015 2014 2013 Net income $ 813,303 $ 757,010 $ 468,850 Statutory capital and surplus $ 5,296,435 $ 5,438,063 $ 4,908,010 The significant variances between SAP and GAAP are that for statutory purposes bonds are carried at amortized cost, acquisition costs are charged to income as incurred, deferred Federal income taxes are subject to limitations, excess and assumed workers’ compensation reserves are discounted at different discount rates and certain assets designated as “non-admitted assets” are charged against surplus. The Commissioner of Insurance of the State of Delaware has allowed BIC to discount non-tabular workers' compensation loss reserves, which is a permitted practice that differs from SAP. The effect of using this permitted practice was to increase BIC’s statutory capital and surplus by $294 million at December 31, 2015 . The National Association of Insurance Commissioners (“NAIC”) has risk-based capital (“RBC”) requirements that require insurance companies to calculate and report information under a risk-based formula which measures statutory capital and surplus needs based on a regulatory definition of risk in a company’s mix of products and its balance sheet. This guidance is used to calculate two capital measurements: Total Adjusted Capital and RBC Authorized Control Level. Total Adjusted Capital is equal to the Company’s statutory capital and surplus excluding capital and surplus derived from the use of permitted practices that differ from statutory accounting practices. RBC Authorized Control Level is the capital level used by regulatory authorities to determine whether remedial action is required. Generally, no remedial action is required if Total Adjusted Capital is 200% or more of the RBC Authorized Control Level. At December 31, 2015 , BIC’s Total Adjusted Capital of $5.002 billion was 456% of its RBC Authorized Control Level. See Note 4, Investments in Fixed Maturity Securities, for a description of assets held on deposit as security.

Common Stockholders' Equity

Common Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Common Stockholders' Equity	Common Stockholders’ Equity The weighted average number of shares used in the computation of net income per share was as follows: 2015 2014 2013 Basic 124,040,313 127,873,708 135,304,752 Diluted 130,188,866 133,651,855 140,742,922 Treasury shares have been excluded from average outstanding shares from the date of acquisition. The difference in calculating basic and diluted net income per share is attributable entirely to the dilutive effect of stock-based compensation plans. Changes in shares of common stock outstanding, net of treasury shares, are presented below. Shares of common stock issued and outstanding do not include shares related to unissued restricted stock units and unexercised stock options. 2015 2014 2013 Balance, beginning of year 126,748,836 132,233,167 136,017,732 Shares issued 1,061,026 332,137 139,790 Shares repurchased (4,502,025 ) (5,816,468 ) (3,924,355) Balance, end of year 123,307,837 126,748,836 132,233,167 The amount of dividends paid is dependent upon factors such as the receipt of dividends from our subsidiaries, our results of operations, cash flow, financial condition and business needs, the capital and surplus requirements of our subsidiaries, and applicable insurance regulations that limit the amount of dividends that may be paid by our regulated insurance subsidiaries.

Fair Value Of Financial Instrum

Fair Value Of Financial Instruments	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Of Financial Instruments	Fair Value Measurements The Company’s fixed maturity and equity securities classified as available for sale and its trading account securities are carried at fair value. Fair value is defined as “the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.” The Company utilizes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three broad levels, as follows: Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 - Quoted prices for similar assets or valuations based on inputs that are observable. Level 3 - Estimates of fair value based on internal pricing methodologies using unobservable inputs. Unobservable inputs are only used to measure fair value to the extent that observable inputs are not available. Substantially all of the Company’s fixed maturity securities were priced by independent pricing services. The prices provided by the independent pricing services are estimated based on observable market data in active markets utilizing pricing models and processes, which may include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, sector groupings, matrix pricing and reference data. The pricing services may prioritize inputs differently on any given day for any security based on market conditions, and not all inputs are available for each security evaluation on any given day. The pricing services used by the Company have indicated that they will only produce an estimate of fair value if objectively verifiable information is available. The determination of whether markets are active or inactive is based upon the volume and level of activity for a particular asset class. The Company reviews the prices provided by pricing services for reasonableness and periodically performs independent price tests of a sample of securities to ensure proper valuation. If prices from independent pricing services are not available for fixed maturity securities, the Company estimates the fair value. For Level 2 securities, the Company utilizes pricing models and processes which may include benchmark yields, sector groupings, matrix pricing, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, bids, offers and reference data. Where broker quotes are used, the Company generally requests two or more quotes and sets a price within the range of quotes received based on its assessment of the credibility of the quote and its own evaluation of the security. The Company generally does not adjust quotes received from brokers. For securities traded only in private negotiations, the Company determines fair value based primarily on the cost of such securities, which is adjusted to reflect prices of recent placements of securities of the same issuer, financial projections, credit quality and business developments of the issuer and other relevant information. For Level 3 securities, the Company generally uses a discounted cash flow model to estimate the fair value of fixed maturity securities. The cash flow models are based upon assumptions as to prevailing credit spreads, interest rate and interest rate volatility, time to maturity and subordination levels. Projected cash flows are discounted at rates that are adjusted to reflect illiquidity, where appropriate. The following tables present the assets and liabilities measured at fair value on a recurring basis as of December 31, 2015 and 2014 by level: (In thousands) Total Level 1 Level 2 Level 3 December 31, 2015 Assets: Fixed maturity securities available for sale: U.S. government and government agency $ 670,419 $ — $ 670,419 $ — State and municipal 4,460,179 — 4,460,179 — Mortgage-backed securities 1,199,859 — 1,199,859 — Asset-backed securities 1,705,172 — 1,704,973 199 Corporate 3,475,038 — 3,474,884 154 Foreign government 837,460 — 837,460 — Total fixed maturity securities available for sale 12,348,127 — 12,347,774 353 Equity securities available for sale: Common stocks 37,273 29,444 — 7,829 Preferred stocks 113,593 — 109,969 3,624 Total equity securities available for sale 150,866 29,444 109,969 11,453 Arbitrage trading account 376,697 256,914 119,607 176 Total $ 12,875,690 $ 286,358 $ 12,577,350 $ 11,982 Liabilities: Trading account securities sold but not yet purchased $ 37,035 $ 35,559 $ 1,476 $ — December 31, 2014 Assets: Fixed maturity securities available for sale: U.S. government and government agency $ 803,388 $ — $ 803,388 $ — State and municipal 4,362,996 — 4,362,996 — Mortgage-backed securities 1,295,636 — 1,295,636 — Asset-backed securities 2,025,926 — 2,005,315 20,611 Corporate 3,174,211 — 3,174,057 154 Foreign government 941,826 — 941,826 — Total fixed maturity securities available for sale 12,603,983 — 12,583,218 20,765 Equity securities available for sale: Common stocks 76,346 65,605 — 10,741 Preferred stocks 94,645 — 90,932 3,713 Total equity securities available for sale 170,991 65,605 90,932 14,454 Arbitrage trading account 450,648 295,047 154,881 720 Total $ 13,225,622 $ 360,652 $ 12,829,031 $ 35,939 Liabilities: Trading account securities sold but not yet purchased $ 106,079 $ 106,074 $ 5 $ — There were no significant transfers between Levels 1 and 2 for the years ended December 31, 2015 and 2014 . The following tables summarize changes in Level 3 assets and liabilities for the years ended December 31, 2015 and 2014 : Gains (Losses) Included in: (In thousands) Beginning Balance Earnings (Losses) Other Comprehensive Income (Losses) Impairments Purchases Sales Paydowns/Maturities Transfers In / Out Ending Balance Year ended December 31, 2015 Assets: Fixed maturity securities available for sale: Asset-backed securities $ 20,611 $ 19 $ 191 $ — $ — $ — $ (1,820 ) $ (18,802 ) $ 199 Corporate 154 — — — — — — — 154 Total 20,765 19 191 — — — (1,820 ) (18,802 ) 353 Equity securities available for sale: Common stocks 10,741 — (273 ) (2,331 ) — (308 ) — — 7,829 Preferred stocks 3,713 (89 ) — — — — — — 3,624 Total 14,454 (89 ) (273 ) (2,331 ) — (308 ) — — 11,453 Arbitrage trading account 720 (799 ) — — 72,640 (71,921 ) — (464 ) 176 Total $ 35,939 $ (869 ) $ (82 ) $ (2,331 ) $ 72,640 $ (72,229 ) $ (1,820 ) $ (19,266 ) $ 11,982 Liabilities: Trading account securities sold but not yet purchased $ — $ — $ — $ — $ — $ — $ — $ — $ — Year ended December 31, 2014 Assets: Fixed maturity securities available for sale: Asset-backed securities $ 42,710 $ 47 $ (3,711 ) $ — $ 238 $ (15,244 ) $ (3,429 ) $ — $ 20,611 Corporate $ 154 $ — $ — $ — $ — $ — $ — $ — $ 154 Total 42,864 47 (3,711 ) — 238 (15,244 ) (3,429 ) — 20,765 Equity securities available for sale: Common stocks 1,238 — (911 ) — 11,343 (929 ) — — 10,741 Preferred stocks 3,752 (17 ) — — 3,430 (3,452 ) — — 3,713 Total 4,990 (17 ) (911 ) — 14,773 (4,381 ) — — 14,454 Arbitrage trading account 1,780 2,274 — — 4,942 (14,073 ) — 5,797 720 Total $ 49,634 $ 2,304 $ (4,622 ) $ — $ 19,953 $ (33,698 ) $ (3,429 ) $ 5,797 $ 35,939 Liabilities: Trading account securities sold but not yet purchased $ — $ (20 ) $ — $ — $ 31 $ (11 ) $ — $ — $ — During the year ended December 31, 2015 , five securities were transferred out of Level 3 as an observable price was available. During the year ended December 31, 2014 , two securities were transferred into Level 3 as quoted prices were no longer available. Fair Value of Financial Instruments The following table presents the carrying amounts and estimated fair values of the Company’s financial instruments as of December 31, 2015 and 2014 : 2015 2014 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Assets: Fixed maturity securities $ 12,444,394 $ 12,462,847 $ 12,705,160 $ 12,725,806 Equity securities available for sale 150,866 150,866 170,991 170,991 Arbitrage trading account 376,697 376,697 450,648 450,648 Loans receivable 273,103 275,747 322,012 325,219 Cash and cash equivalents 763,631 763,631 674,441 674,441 Trading accounts receivable from brokers and clearing organizations 383,115 383,115 371,034 371,034 Due from broker 1,713 1,713 — — Liabilities: Due to broker — — 23,133 23,133 Trading account securities sold but not yet purchased 37,035 37,035 106,079 106,079 Subordinated debentures 340,320 355,880 340,060 332,640 Senior notes and other debt 1,844,621 2,029,572 2,115,527 2,344,292 The estimated fair values of the Company’s fixed maturity securities, equity securities available for sale and arbitrage trading account securities are based on various valuation techniques that rely on fair value measurements as described in Note 13 above. The fair value of loans receivable are estimated by using current institutional purchaser yield requirements for loans with similar credit characteristics, which is considered a Level 2 input. The fair value of the senior notes and other debt and the subordinated debentures is based on spreads for similar securities, which is considered a Level 2 input.

Lease Obligations

Lease Obligations	12 Months Ended
	Dec. 31, 2015
Leases [Abstract]
Lease Obligations	Lease Obligations The Company and its subsidiaries use office space and equipment under leases expiring at various dates. These leases are considered operating leases for financial reporting purposes. Some of these leases have options to extend the length of the leases and contain clauses for cost of living, operating expense and real estate tax adjustments. Future minimum lease payments, without provision for sublease income, are: $ 42,470,000 in 2016 ; $ 39,443,000 in 2017 ; $ 35,286,000 in 2018 ; $ 30,941,000 in 2019 ; $28,584,000 in 2020 and $ 105,825,000 thereafter. Rental expense was $ 46,271,000 , $ 45,198,000 and $ 44,752,000 for 2015 , 2014 and 2013 , respectively.

Commitments, Litigation And Con

Commitments, Litigation And Contingent Liabilities	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments, Litigation And Contingent Liabilities	Commitments, Litigation and Contingent Liabilities In the ordinary course of business, the Company is subject to disputes, litigation and arbitration arising from its insurance and reinsurance businesses. These matters are generally related to insurance and reinsurance claims and are considered in the establishment of loss and loss expense reserves. In addition, the Company may also become involved in legal actions which seek extra-contractual damages, punitive damages or penalties, including claims alleging bad faith in handling of insurance claims. The Company expects its ultimate liability with respect to such matters will not be material to its financial condition. However, adverse outcomes on such matters are possible, from time to time, and could be material to the Company’s results of operations in any particular financial reporting period. At December 31, 2015 , the Company had commitments to invest up to $117 million and $485 million in certain investment funds and real estate construction projects, respectively.

Stock Incentive Plan

Stock Incentive Plan	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Incentive Plan	Stock Incentive Plan The Company has not issued any stock options under its stock incentive plans since 2004, and there were no outstanding options at December 31, 2015 and December 31, 2014 . Pursuant to the stock incentive plan, the Company may issue restricted stock units (RSUs) to employees of the Company and its subsidiaries. The RSUs generally vest three to five years from the award date and are subject to other vesting and forfeiture provisions contained in the award agreement. The following table summarizes RSU information for the three years ended December 31, 2015 : 2015 2014 2013 RSUs granted and unvested at beginning of period: 5,330,445 4,491,520 4,701,120 Granted 997,522 1,154,950 108,400 Vested (1,938,000 ) (81,500 ) (146,250 ) Canceled (231,642 ) (234,525 ) (171,750 ) RSUs granted and unvested at end of period: 4,158,325 5,330,445 4,491,520 Upon vesting, shares of the Company’s common stock equal to the number of vested RSUs are issued or deferred to a later date, depending on the terms of the specific award agreement. As of December 31, 2015 , 4,275,474 RSUs had been deferred. RSUs that have not yet vested and vested RSUs that have been deferred are not considered to be issued and outstanding shares. The fair value of RSUs at the date of grant are recorded as unearned compensation, a component of stockholders’ equity, and expensed over the vesting period. Following is a summary of changes in unearned compensation for the three years ended December 31, 2015 : (In thousands) 2015 2014 2013 Unearned compensation at beginning of year $ 88,015 $ 73,205 $ 93,653 RSUs granted, net of cancellations 50,442 51,575 4,406 RSUs expensed (30,691 ) (27,966 ) (22,881 ) RSUs forfeitures (4,228 ) (8,799 ) (1,973 ) Unearned compensation at end of year $ 103,538 $ 88,015 $ 73,205

Compensation Plans

Compensation Plans	12 Months Ended
	Dec. 31, 2015
Compensation Related Costs [Abstract]
Compensation Plans	Compensation Plans The Company and its subsidiaries have profit sharing plans in which substantially all employees participate. The plans provide for minimum annual contributions of 5% of eligible compensation; contributions above the minimum are discretionary and vary with each participating subsidiary’s profitability. Employees will become eligible to participate in the plan on the first day of the calendar quarter following the first full calendar quarter after the employee's date of hire provided the employee has completed 250 hours of service during the calendar quarter. The plans provide that 40% of the contributions vest immediately and that the remaining 60% vest at varying percentages based upon years of service. Profit sharing expense was $42 million , $38 million , and $34 million in 2015 , 2014 and 2013 , respectively. The Company has a long-term incentive compensation plan ("LTIP") that provides for incentive compensation to key executives based on the growth in the company's book value per share over a five year period. The following table summarizes the outstanding LTIP awards as of December 31, 2015 : Units Outstanding Maximum Value Inception to date earned through December 31, 2015 on outstanding units 2011 grant 172,850 $ 43,212,500 $ 34,331,000 2013 grant 204,500 51,125,000 23,804,000 2014 grant 216,750 21,675,000 6,559,000 2015 grant 213,250 21,325,000 3,205,000 The following table summarizes the LTIP expense for each of the three years ended December 31, 2015 : (In thousands) 2015 2014 2013 2011 grant $ 7,397 $ 9,855 $ 6,939 2013 grant 7,336 9,493 7,231 2014 grant 2,935 3,663 — 2015 grant 3,205 — — Total $ 20,873 $ 23,011 $ 14,170

Retirement Benefits

Retirement Benefits	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Retirement Benefits	Retirement Benefits The Company and its executive chairman of the board entered into an unfunded supplemental benefit agreement (SBA) in 2004. On March 28, 2013, the Company agreed to terminate and distribute the retirement benefit of the SBA. As a result, the Company distributed retirement benefits of $0.3 million and $4.6 million in 2013 and 2014 , respectively. The final retirement benefit of $59.4 million , which was fully accrued at December 31, 2014, was distributed in 2015 . Net retirement benefit expense was $13,357,000 , $9,994,000 and none in 2013 , 2014 , and 2015 respectively.

Supplemental Financial Statemen

Supplemental Financial Statement Information	12 Months Ended
	Dec. 31, 2015
Other Income and Expenses [Abstract]
Supplemental Financial Statement Data	Supplemental Financial Statement Data Other operating costs and expenses consist of the following: (In thousands) 2015 2014 2013 Amortization of deferred policy acquisition costs $ 1,102,492 $ 1,053,397 $ 991,070 Other underwriting expenses 903,006 843,133 780,058 Service company expenses 127,365 102,726 88,662 Net foreign currency losses (gains) 400 (27 ) (10,120 ) Other costs and expenses 156,487 158,227 151,014 Total $ 2,289,750 $ 2,157,456 $ 2,000,684

Industry Segments

Industry Segments	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Industry Segments	Industry Segments The Company’s reportable segments include the following three business segments, plus a corporate segment: • Insurance-Domestic - commercial insurance business, including excess and surplus lines and admitted lines, primarily throughout the United States; • Insurance-International - insurance business primarily in the United Kingdom, Continental Europe, South America, Canada, Scandinavia, Asia, and Australia; • Reinsurance-Global - reinsurance business on a facultative and treaty basis, primarily in the United States, United Kingdom, Continental Europe, Australia, the Asia-Pacific Region, and South Africa. The accounting policies of the segments are the same as those described in the summary of significant accounting policies. Income tax expense and benefits are calculated based upon the Company’s overall effective tax rate. Summary financial information about the Company’s reporting segments is presented in the following table. Income (loss) before income taxes by segment includes allocated investment income. Identifiable assets by segment are those assets used in or allocated to the operation of each segment. Revenues (In thousands) Earned Premiums Investment Income Other Total Pre-Tax Income (Loss) Net Income (Loss) December 31, 2015: Insurance-Domestic $ 4,659,359 $ 358,935 $ 96,487 $ 5,114,781 $ 724,667 $ 495,082 Insurance-International 772,141 51,522 — 823,663 51,926 37,204 Reinsurance-Global 609,109 74,226 — 683,335 94,852 66,627 Corporate, other and eliminations(1) — 27,962 464,392 492,354 (231,739 ) (155,230 ) Net investment gains — — 92,324 92,324 92,324 60,011 Consolidated $ 6,040,609 $ 512,645 $ 653,203 $ 7,206,457 $ 732,030 $ 503,694 December 31, 2014: Insurance-Domestic $ 4,271,933 $ 428,632 $ 106,853 $ 4,807,418 $ 796,309 $ 539,461 Insurance-International 802,375 55,407 — 857,782 29,779 22,182 Reinsurance-Global 670,110 88,821 — 758,931 115,677 79,720 Corporate, other and eliminations(1) — 28,025 421,920 449,945 (244,421 ) (158,133 ) Net investment gains — — 254,852 254,852 254,852 165,654 Consolidated $ 5,744,418 $ 600,885 $ 783,625 $ 7,128,928 $ 952,196 $ 648,884 December 31, 2013: Insurance-Domestic $ 3,782,416 $ 404,280 $ 107,517 $ 4,294,213 $ 648,740 $ 449,981 Insurance-International 723,151 47,039 — 770,190 56,922 40,292 Reinsurance-Global 720,970 89,090 — 810,060 110,425 78,013 Corporate, other and eliminations(1) — 3,882 408,645 412,527 (238,743 ) (142,479 ) Net investment gains — — 121,544 121,544 121,544 74,118 Consolidated $ 5,226,537 $ 544,291 $ 637,706 $ 6,408,534 $ 698,888 $ 499,925 Identifiable Assets (In thousands) December 31, 2015 December 31, 2014 Insurance-Domestic $ 16,351,737 $ 16,065,409 Insurance-International 1,711,993 1,879,438 Reinsurance-Global 2,441,340 2,713,554 Corporate, other and eliminations(1) 1,225,897 1,058,290 Consolidated $ 21,730,967 $ 21,716,691 _______________________________________ (1) Corporate, other and eliminations represent corporate revenues and expenses and other items that are not allocated to business segments. Net premiums earned by major line of business are as follows: (In thousands) 2015 2014 2013 Insurance-Domestic Other liability $ 1,546,157 $ 1,449,425 $ 1,259,376 Workers' compensation 1,269,785 1,126,704 995,047 Short-tail lines 925,468 875,898 774,809 Commercial automobile 548,450 526,344 486,759 Professional liability 369,499 293,562 266,425 Total Insurance-Domestic 4,659,359 4,271,933 3,782,416 Insurance-International Other liability 103,974 92,411 65,528 Workers' compensation 93,728 71,997 84,637 Short-tail lines 373,415 415,123 336,814 Commercial automobile 125,628 116,369 130,020 Professional liability 75,396 106,475 106,152 Total Insurance-International 772,141 802,375 723,151 Reinsurance-Global Casualty 421,811 487,264 507,790 Property 187,298 182,846 213,180 Total Reinsurance-Global 609,109 670,110 720,970 Total $ 6,040,609 $ 5,744,418 $ 5,226,537

Quarterly Financial Information

Quarterly Financial Information (Unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (Unaudited)	Quarterly Financial Information (Unaudited) The following is a summary of quarterly financial data: (In thousands. except per share data) 2015 Three months ended March 31 June 30 September 30 December 31 Revenues $ 1,744,679 $ 1,789,765 $ 1,860,957 $ 1,811,056 Net income 118,307 123,035 152,607 109,745 Net income per share(1) Basic 0.94 0.99 1.24 0.89 Diluted 0.89 0.95 1.18 0.85 2014 Three months ended March 31 June 30 September 30 December 31 Revenues $ 1,706,906 $ 1,796,989 $ 1,840,605 $ 1,784,428 Net income 169,673 179,961 188,539 110,711 Net income per share(1) Basic 1.31 1.41 1.48 0.87 Diluted 1.25 1.35 1.42 0.83 _______________________________________ (1) Net income per share (“EPS”) in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Thus, the sum of the four quarters EPS does not necessarily equal the full-year EPS.

Schedule II - Condensed Financi

Schedule II - Condensed Financial Information of Registrant	12 Months Ended
	Dec. 31, 2013
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Schedule II - Condensed Financial Information of Registrant	Schedule II W. R. Berkley Corporation Condensed Financial Information of Registrant Balance Sheets (Parent Company) December 31, (In thousands) 2015 2014 Assets: Cash and cash equivalents $ 195,658 $ 90,693 Fixed maturity securities available for sale at fair value (cost $201,256 and $272,283 at December 31, 2015 and 2014, respectively) 201,738 273,773 Equity securities available for sale, at fair value (cost $3,430 in 2015 and $3,738 in 2014) 3,430 3,738 Investment in subsidiaries 6,454,065 6,693,731 Deferred Federal income taxes 37,135 — Current Federal income taxes 51,512 62,882 Property, furniture and equipment at cost, less accumulated depreciation 13,150 9,852 Other assets 6,153 6,978 Total assets $ 6,962,841 $ 7,141,647 Liabilities and stockholders’ equity Liabilities: Due to subsidiaries $ 143,669 $ 87,540 Other liabilities 115,737 162,648 Deferred Federal income taxes — 149 Subordinated debentures 340,320 340,060 Senior notes 1,762,869 1,961,305 Total liabilities 2,362,595 2,551,702 Stockholders’ equity: Preferred stock — — Common stock 47,024 47,024 Additional paid-in capital 1,005,455 991,512 Retained earnings (including accumulated undistributed net income of subsidiaries of $4,746,934 and $4,700,821 at December 31, 2015 and 2014, respectively) 6,178,070 5,732,410 Accumulated other comprehensive income (loss) (66,698 ) 183,550 Treasury stock, at cost (2,563,605 ) (2,364,551 ) Total stockholders’ equity 4,600,246 4,589,945 Total liabilities and stockholders’ equity $ 6,962,841 $ 7,141,647 ________________ See accompanying Report of Independent Registered Public Accounting Firm and note to condensed financial statements. Schedule II, Continued W. R. Berkley Corporation Condensed Financial Information of Registrant, Continued Statements of Income (Parent Company) Years Ended December 31, (In thousands) 2015 2014 2013 Management fees and investment income including dividends from subsidiaries of $642,421, $503,483, and $269,626 for the years ended December 31, 2015, 2014 and 2013, respectively $ 655,318 $ 515,775 $ 277,223 Net investment gains 696 5,487 24,550 Other income 348 450 223 Total revenues 656,362 521,712 301,996 Operating costs and expense 143,391 148,288 122,562 Interest expense 128,248 125,352 120,066 Income before federal income taxes 384,723 248,072 59,368 Federal income taxes: Federal income taxes provided by subsidiaries on a separate return basis 272,180 366,721 225,845 Federal income tax expense on a consolidated return basis (199,322 ) (273,310 ) (154,928 ) Net expense 72,858 93,411 70,917 Income before undistributed equity in net income of subsidiaries 457,581 341,483 130,285 Equity in undistributed net income of subsidiaries 46,113 307,401 369,640 Net income $ 503,694 $ 648,884 $ 499,925 ________________ See accompanying Report of Independent Registered Public Accounting Firm and note to condensed financial statements. Schedule II, Continued W. R. Berkley Corporation Condensed Financial Information of Registrant, Continued Statements of Cash Flows (Parent Company) Years Ended December 31, (In thousands) 2015 2014 2013 Cash flows from (used in) from operating activities: Net income $ 503,694 $ 648,884 $ 499,925 Adjustments to reconcile net income to net cash from operating activities: Net investment gains (696 ) (5,487 ) (24,550 ) Depreciation and amortization 2,693 2,916 10,397 Equity in undistributed earnings of subsidiaries (46,113 ) (307,401 ) (369,640 ) Tax payments received from subsidiaries 311,482 462,809 77,305 Federal income taxes provided by subsidiaries on a separate return basis (272,180 ) (366,721 ) (225,845 ) Stock incentive plans 29,725 28,068 23,784 Change in: Federal income taxes 51,772 (15,239 ) 21,866 Other assets 301 (364 ) (821 ) Other liabilities (92,752 ) (39,780 ) (15,470 ) Accrued investment income 524 (820 ) 967 Net cash from (used in) operating activities 488,450 406,865 (2,082 ) Cash from (used in) investing activities: Proceeds from sales of fixed maturity securities 380,986 289,683 230,854 Proceeds from maturities and prepayments of fixed maturity securities 123,639 103,646 68,918 Proceeds from sales of equity securities 308 7,356 23,395 Cost of purchases of fixed maturity securities (432,645 ) (605,768 ) (79,132 ) Cost of purchases of equity securities — — (4,668 ) Cost of acquired companies — (82,879 ) — Investments in and advances to subsidiaries, net 30,338 34,191 (58,454 ) Change in balance due to security broker — (2,151 ) 6,918 Net additions to real estate, furniture & equipment (4,425 ) (1,615 ) (1,896 ) Net cash from (used in) investing activities 98,201 (257,537 ) 185,935 Cash from (used in) financing activities: Net proceeds from issuance of senior notes — 344,472 339,627 Net proceeds from stock options exercised — — 53 Repayment of senior notes (200,000 ) — (450,000 ) Purchase of common treasury shares (223,652 ) (238,933 ) (166,473 ) Cash dividends to common stockholders (58,034 ) (181,489 ) (52,717 ) Net cash from (used in) financing activities (481,686 ) (75,950 ) (329,510 ) Net increase (decrease) in cash and cash equivalents 104,965 73,378 (145,657 ) Cash and cash equivalents at beginning of year 90,693 17,315 162,972 Cash and cash equivalents at end of year $ 195,658 $ 90,693 $ 17,315 ________________ See accompanying Report of Independent Registered Public Accounting Firm and note to condensed financial statements. W. R. Berkley Corporation Condensed Financial Information of Registrant,Continued December 31, 2015 Note to Condensed Financial Statements (Parent Company) The accompanying condensed financial statements should be read in conjunction with the notes to consolidated financial statements included elsewhere herein. Reclassifications have been made in the 2014 and 2013 financial statements as originally reported to conform them to the presentation of the 2015 financial statements. The Company files a consolidated federal tax return with the results of its domestic insurance subsidiaries included on a statutory basis. Under present Company policy, federal income taxes payable by subsidiary companies on a separate-return basis are paid to W. R. Berkley Corporation, and the Company pays the tax due on a consolidated return basis.

Schedule III - Supplementary In

Schedule III - Supplementary Insurance Information	12 Months Ended
	Dec. 31, 2015
Supplementary Insurance Information [Abstract]
Schedule III - Supplementary Insurance Information	Schedule III W. R. Berkley Corporation and Subsidiaries Supplementary Insurance Information December 31, 2015, 2014 and 2013 (In thousands) Deferred Policy Acquisition Cost Reserve for Losses and Loss Expenses Unearned Premiums Net Premiums Earned Net Investment Income Loss and Loss Expenses Amortization of Deferred Policy Acquisition Cost Other Operating Cost and Expenses Net Premiums Written December 31, 2015 Insurance-Domestic $ 367,977 $ 8,450,190 $ 2,529,931 $ 4,659,359 $ 358,935 $ 2,851,136 $ 760,020 $ 778,957 $ 4,812,830 Insurance-International 62,687 798,116 324,530 772,141 51,522 449,147 169,962 152,629 778,567 Reinsurance-Global 82,464 1,420,844 282,672 609,109 74,226 355,987 172,510 59,986 598,118 Corporate and adjustments — — — — 27,962 — — 195,686 — Total $ 513,128 $ 10,669,150 $ 3,137,133 $ 6,040,609 $ 512,645 $ 3,656,270 $ 1,102,492 $ 1,187,258 $ 6,189,515 December 31, 2014 Insurance-Domestic $ 347,261 $ 8,000,863 $ 2,384,511 $ 4,271,933 $ 428,632 $ 2,571,010 $ 710,141 $ 729,958 $ 4,517,587 Insurance-International 60,900 855,852 342,746 802,375 55,407 503,997 173,877 150,129 828,076 Reinsurance-Global 80,364 1,512,986 299,475 670,110 88,821 415,560 169,379 58,315 651,284 Corporate and adjustments — — — — 28,025 — — 165,657 — Total $ 488,525 $ 10,369,701 $ 3,026,732 $ 5,744,418 $ 600,885 $ 3,490,567 $ 1,053,397 $ 1,104,059 $ 5,996,947 December 31, 2013 Insurance-Domestic $ 306,464 $ 7,715,124 $ 2,107,768 $ 3,782,416 $ 404,280 $ 2,318,541 $ 651,524 $ 671,096 $ 3,994,387 Insurance-International 60,751 672,009 317,691 723,151 47,039 429,900 152,843 124,497 756,185 Reinsurance-Global 84,886 1,693,808 355,978 720,970 89,090 448,583 186,703 64,567 749,601 Corporate and adjustments — — — — 3,882 — — 149,454 — Total $ 452,101 $ 10,080,941 $ 2,781,437 $ 5,226,537 $ 544,291 $ 3,197,024 $ 991,070 $ 1,009,614 $ 5,500,173 See accompanying Report of Independent Registered Public Accounting Firm.

Schedule IV - Reinsurance

Schedule IV - Reinsurance	12 Months Ended
	Dec. 31, 2015
Supplemental Schedule of Reinsurance Premiums for Insurance Companies [Abstract]
Schedule IV - Reinsurance	Schedule IV W. R. Berkley Corporation and Subsidiaries Reinsurance Years ended December 31, 2015, 2014 and 2013 Premiums Written (In thousands, other than percentages) Direct Amount Ceded to Other Companies Assumed from Other Companies Net Amount Percentage of Amount Assumed to Net Year ended December 31, 2015: Insurance-Domestic $ 5,521,447 $ 871,358 $ 162,741 $ 4,812,830 3.4 % Insurance-International 874,359 144,737 48,945 778,567 6.3 % Reinsurance-Global 16,727 44,383 625,774 598,118 104.6 % Total $ 6,412,533 $ 1,060,478 $ 837,460 $ 6,189,515 13.5 % Year ended December 31, 2014: Insurance-Domestic $ 5,214,849 $ 866,092 $ 168,830 $ 4,517,587 3.7 % Insurance-International 927,799 156,195 56,472 828,076 6.8 % Reinsurance-Global 42,594 43,604 652,294 651,284 100.2 % Total $ 6,185,242 $ 1,065,891 $ 877,596 $ 5,996,947 14.6 % Year ended December 31, 2013: Insurance-Domestic $ 4,699,348 $ 809,368 $ 104,407 $ 3,994,387 2.6 % Insurance-International 887,027 142,591 11,749 756,185 1.6 % Reinsurance-Global 39,797 58,959 768,763 749,601 102.6 % Total $ 5,626,172 $ 1,010,918 $ 884,919 $ 5,500,173 16.1 % See accompanying Report of Independent Registered Public Accounting Firm.

Schedule V - Valuation and Qual

Schedule V - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2015
Valuation and Qualifying Accounts [Abstract]
Schedule V - Valuation and Qualifying Accounts	Schedule V W. R. Berkley Corporation and Subsidiaries Valuation and Qualifying Accounts Years ended December 31, 2015, 2014 and 2013 (In thousands) Opening Balance Additions- Charged to Expense Deduction- Amounts Written Off Ending Balance Year ended December 31, 2015: Premiums and fees receivable $ 21,446 $ 6,281 $ (5,203 ) $ 22,524 Due from reinsurers 1,144 (24 ) (100 ) 1,020 Deferred federal and foreign income taxes 1,335 2,702 — 4,037 Loan loss reserves 2,486 (392 ) — 2,094 Total $ 26,411 $ 8,567 $ (5,303 ) $ 29,675 Year ended December 31, 2014: Premiums and fees receivable $ 20,951 $ 5,944 $ (5,449 ) $ 21,446 Due from reinsurers 1,385 301 (542 ) 1,144 Deferred federal and foreign income taxes — 1,335 — 1,335 Loan loss reserves 2,087 399 — 2,486 Total $ 24,423 $ 7,979 $ (5,991 ) $ 26,411 Year ended December 31, 2013: Premiums and fees receivable $ 22,919 $ 3,133 $ (5,101 ) $ 20,951 Due from reinsurers 1,680 186 (481 ) 1,385 Loan loss reserves 5,620 308 (3,841 ) 2,087 Total $ 30,219 $ 3,627 $ (9,423 ) $ 24,423 See accompanying Report of Independent Registered Public Accounting Firm.

Schedule VI - Supplementary Inf

Schedule VI - Supplementary Information Concerning Property-Casualty Insurance Operations	12 Months Ended
	Dec. 31, 2015
Supplemental Information for Property, Casualty Insurance Underwriters [Abstract]
Schedule VI - Supplementary Information Concerning Property-Casualty Insurance Operations	Schedule VI W. R. Berkley Corporation and Subsidiaries Supplementary Information Concerning Property-Casualty Insurance Operations Years Ended December 31, 2015, 2014 and 2013 (In thousands) 2015 2014 2013 Deferred policy acquisition costs $ 513,128 $ 488,525 $ 452,101 Reserves for losses and loss expenses 10,669,150 10,369,701 10,080,941 Unearned premium 3,137,133 3,026,732 2,781,437 Net premiums earned 6,040,609 5,744,418 5,226,537 Net investment income 512,645 600,885 544,291 Losses and loss expenses incurred: Current year 3,653,561 3,495,825 3,221,393 Prior years (46,713 ) (75,764 ) (78,810 ) Loss reserve discount accretion 49,422 70,506 54,441 Amortization of deferred policy acquisition costs 1,102,492 1,053,397 991,070 Paid losses and loss expenses 3,257,015 3,115,227 2,878,071 Net premiums written 6,189,515 5,996,947 5,500,173 See accompanying Report of Independent Registered Public Accounting Firm.

Summary of Significant Accoun41

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Principles of consolidation and basis of presentation	Principles of consolidation and basis of presentation The consolidated financial statements, which include the accounts of W. R. Berkley Corporation and its subsidiaries (the "Company"), have been prepared on the basis of U.S. generally accepted accounting principles ("GAAP"). All significant intercompany transactions and balances have been eliminated. Reclassifications have been made in the 2014 and 2013 financial statements to conform to the presentation of the 2015 financial statements. 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 and disclosures of contingent assets and liabilities at the date of the financial statements and the revenues and expenses reflected during the reporting period. The most significant items on our balance sheet that involve a greater degree of accounting estimates that are subject to change in the future are the valuation of investments, other-than-temporary impairments, loss and loss expense reserves and premium estimates. Actual results could differ from those estimates.
Revenue recognition	Revenue recognition Insurance premiums are recognized as written at the inception of the policy. Reinsurance premiums are estimated based upon information received from ceding companies, and subsequent differences from such estimates are recorded in the period they are determined. Insurance and reinsurance premiums are primarily earned on a pro rata basis over the policy term. Fees for services are earned over the period that the services are provided. Audit premiums are recognized when they are reliably determinable. The change in accruals for earned but unbilled audit premiums increased net premiums written and premiums earned by $3 million , $9 million and $12 million in 2015 , 2014 and 2013 , respectively. Revenues from wholly-owned investees are derived from aircraft services provided to the general, commercial and military aviation markets. These services include (i) the distribution, manufacturing, repair and overhaul of aircraft parts and components, (ii) the sale of new and used aircraft, and (iii) avionics, fuel, maintenance, storage and charter services. Revenue is recognized upon the shipment of parts, the delivery of aircraft, the delivery of fuel, and upon completion of services.
Cash and cash equivalents	Cash and cash equivalents Cash equivalents consist of funds invested in money market accounts and investments with an effective maturity of three months or less when purchased.
Investments	Investments Fixed maturity securities classified as available for sale are carried at estimated fair value, with unrealized gains and losses, net of applicable income taxes, excluded from earnings and reported as a component of comprehensive income and a separate component of stockholders' equity. Fixed maturity securities that the Company has the positive intent and ability to hold to maturity are classified as held to maturity and reported at amortized cost. Investment income from fixed maturity securities is recognized based on the constant effective yield method. Premiums and discounts on mortgage-backed securities are adjusted for the effects of actual and anticipated prepayments on a retrospective basis. Equity securities classified as available for sale are carried at estimated fair value, with unrealized gains and losses, net of applicable income taxes, excluded from earnings and reported as a component of comprehensive income and a separate component of stockholders' equity. Equity and fixed maturity securities that the Company purchased with the intent to sell in the near-term are classified as trading account securities and are reported at estimated fair value. Realized and unrealized gains and losses from trading activity are reported as net investment income and are recorded at the trade date. Short sales and short call options are presented as trading securities sold but not yet purchased. Unsettled trades and the net margin balances held by the clearing broker are presented as a trading account receivable from brokers and clearing organizations. Investment funds are carried under the equity method of accounting. For certain investment funds, the Company's share of the earnings or losses is reported on a one-quarter lag in order to facilitate the timely completion of the Company's consolidated financial statements. Loans receivable primarily represent commercial real estate mortgage loans and bank loans and are carried at amortized cost. The Company monitors the performance of its loans receivable and establishes an allowance for loan losses for loans where the Company determines it is probable that the contractual terms will not be met, with a corresponding charge to earnings. For loans that are evaluated individually and deemed to be impaired, the Company establishes a specific allowance based on a discounted cash flow analysis and comparable cost and sales methodologies, if appropriate. Individual loans that are not considered impaired and smaller-balance homogeneous loans are evaluated collectively and a general allowance is established if it is considered probable that a loss has been incurred. The accrual of interest on loans receivable is discontinued if the loan is 90 days past due based on the contractual terms of the loan unless the loan is adequately secured and in process of collection. In general, loans are placed on non-accrual status or charged off at an earlier date if collection of principal or interest is considered doubtful. Interest on these loans is accounted for on a cash basis until qualifying for return to accrual status. Loans are returned to accrual status when all principal and interest amounts contractually due are brought current and future payments are reasonably assured. Fair value is defined as “the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.” Fair value of investments is determined based on a fair value hierarchy that prioritizes the use of observable inputs over the use of unobservable inputs and requires the use of observable inputs when available. (See Note 13 of the Notes to Consolidated Financial Statements.) Realized gains or losses represent the difference between the cost of securities sold and the proceeds realized upon sale and are recorded at the trade date. The Company uses primarily the first-in, first-out method to determine the cost of securities sold. The cost of securities is adjusted where appropriate to include a provision for a decline in value which is considered to be other than temporary. An other-than-temporary decline is considered to occur in investments where there has been a sustained reduction in fair value and where the Company does not expect to recover the cost basis of the investment prior to the time of sale or maturity. Since equity securities do not have a contractual cash flow or a maturity, the Company considers whether the price of an equity security is expected to recover within a reasonable period of time. For fixed maturity securities that the Company intends to sell or, more likely than not, would be required to sell, a decline in value below amortized cost is considered to be an other-than-temporary impairment (“OTTI”). The amount of OTTI is equal to the difference between amortized cost and fair value at the balance sheet date. For fixed maturity securities that the Company does not intend to sell or believes that it is more likely than not it would not be required to sell, a decline in value below amortized cost is considered to be an OTTI if the Company does not expect to recover the entire amortized cost basis of a security (i.e., the present value of cash flows expected to be collected is less than the amortized cost basis of the security). The portion of the decline in value considered to be a credit loss (i.e., the difference between the present value of cash flows expected to be collected and the amortized cost basis of the security) is recognized in earnings. The portion of the decline in value not considered to be a credit loss (i.e., the difference in the present value of cash flows expected to be collected and the fair value of the security) is recognized in other comprehensive income. Impairment assessments for structured securities, including mortgage-backed securities and asset-backed securities, collateralized debt obligations and corporate debt, are generally evaluated based on the performance of the underlying collateral under various economic and default scenarios that may involve subjective judgments and estimates by management. Modeling these securities involves various factors, such as projected default rates, the nature and realizable value of the collateral, if any, the ability of the issuer to make scheduled payments, historical performance and other relevant economic and performance factors. If an OTTI determination is made, a discounted cash flow analysis is used to ascertain the amount of the credit impairment. Real estate held for investment purposes is initially recorded at the purchase price, which is generally fair value, and is subsequently reported at cost less accumulated depreciation. Real estate taxes, interest and other costs incurred during development and construction are capitalized. Buildings are depreciated on a straight-line basis over the estimated useful lives of the building. Minimum rental income is recognized on a straight-line basis over the lease term. Income and expenses from real estate are reported as net investment income. The carrying value of real estate is reviewed for impairment and an impairment loss is recognized if the estimated undiscounted cash flows from the use and disposition of the property are less than the carrying value of the property.
Per share data	Per share data The Company presents both basic and diluted net income per share (“EPS”) amounts. Basic EPS is calculated by dividing net income by weighted average number of common shares outstanding during the year. Diluted EPS is based upon the weighted average number of common and common equivalent shares outstanding during the year and is calculated using the treasury stock method for stock incentive plans. Common equivalent shares are excluded from the computation in periods in which they have an anti-dilutive effect. Stock options for which the exercise price exceeds the average market price over the period have an anti-dilutive effect on EPS and, accordingly, are excluded from the calculation.
Deferred policy acquisition costs	Deferred policy acquisition costs Acquisition costs associated with the successful acquisition of new and renewed insurance and reinsurance contracts are deferred and amortized ratably over the terms of the related contracts. Ceding commissions received on reinsurance contracts are netted against acquisition costs and are recognized ratably over the life of the contract. Deferred policy acquisition costs are presented net of unearned ceding commissions. Deferred policy acquisition costs are comprised primarily of commissions, as well as employment-related underwriting costs and premium taxes. Deferred policy acquisition costs are reviewed to determine if they are recoverable from future income and, if not, are charged to expense. The recoverability of deferred policy acquisition costs is evaluated separately by each of our operating companies for each of their major lines of business. Future investment income is taken into account in measuring the recoverability of deferred policy acquisition costs.
Reserves for losses and loss expenses	Reserves for losses and loss expenses Reserves for losses and loss expenses are an accumulation of amounts determined on the basis of (1) evaluation of claims for business written directly by the Company; (2) estimates received from other companies for reinsurance assumed by the Company; and (3) estimates for losses incurred but not reported (based on Company and industry experience). These estimates are periodically reviewed and, as experience develops and new information becomes known, the reserves are adjusted as necessary. Such adjustments are reflected in the statements of income in the period in which they are determined. The Company discounts its reserves for excess and assumed workers' compensation claims using a risk-free or statutory rate.
Reinsurance ceded	Reinsurance ceded The unearned portion of premiums ceded to reinsurers is reported as prepaid reinsurance premiums and earned ratably over the policy term. The estimated amounts of reinsurance recoverable on unpaid losses are reported as due from reinsurers. To the extent any reinsurer does not meet its obligations under reinsurance agreements, the Company must discharge its liability. Amounts due from reinsurers are reflected net of funds held where the right of offset is present. The Company has provided reserves for estimated uncollectible reinsurance.
Deposit accounting	Deposit accounting Contracts that do not meet the risk transfer requirements of GAAP are accounted for using the deposit accounting method. Under this method, an asset or liability is recognized at the inception of the contract based on consideration paid or received. The amount of the deposit asset or liability is adjusted at subsequent reporting dates using the interest method with a corresponding credit or charge to interest income or expense.
Federal and foreign income taxes	Federal and foreign income taxes The Company files a consolidated income tax return in the U.S. and foreign tax returns in countries where it has overseas operations. The Company's method of accounting for income taxes is the asset and liability method. Under this method, deferred tax assets and liabilities are measured using tax rates currently in effect or expected to apply in the years in which those temporary differences are expected to reverse. Interest and penalties, if any, are reported as income tax expense. The Company believes there are no tax positions that would require disclosure under GAAP. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that all or a portion of the deferred tax assets will not be realized.
Foreign currency	Foreign currency Gains and losses resulting from foreign currency transactions (transactions denominated in a currency other than the entity's functional currency) are reported on the statements of income as other operating costs and expenses. Unrealized gains or losses resulting from translating the results of non-U.S. dollar denominated operations are reported in accumulated other comprehensive income. Revenues and expenses denominated in currencies other than U.S. dollars are translated at the weighted average exchange rate during the year. Assets and liabilities are translated at the rate of exchange in effect at the balance sheet date.
Property, furniture and equipment	Property, furniture and equipment Property, furniture and equipment are carried at cost less accumulated depreciation. Depreciation is calculated using the estimated useful lives of the respective assets.
Comprehensive income	Comprehensive income Comprehensive income encompasses all changes in stockholders' equity (except those arising from transactions with stockholders) and includes net income, net unrealized holding gains or losses on available for sale securities, unrealized foreign currency translation adjustments and changes in unrecognized pension obligations.
Goodwill and other intangible assets	Goodwill and other intangible assets Goodwill and other intangible assets are tested for impairment on an annual basis and at interim periods where circumstances require.
Stock options	Stock options The costs resulting from all share-based payment transactions with employees are recognized in the consolidated financial statements using a fair-value-based measurement method.
Recent accounting pronouncements	Recent accounting pronouncements The accounting and reporting standards that became effective in 2015 were either not applicable to the Company or their adoption did not have a material impact on the Company. Accounting and reporting standards that are not yet effective: In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, Revenue from Customers. ASU 2014-09 clarifies the principles for recognizing revenue. While insurance contracts are not within the scope of this updated guidance, the Company’s insurance service fee revenue will be subject to this updated guidance. The updated guidance requires an entity to recognize revenue as performance obligations are met, in order to reflect the transfer of promised goods or services to customers in an amount that reflects the consideration the entity is entitled to receive for those goods or services. The updated guidance, as amended by ASU 2015-14, is effective for public business entities for annual and interim reporting periods beginning after December 15, 2017. The adoption of this guidance is not expected to have a material effect on the Company’s financial condition or results of operations. In February 2015, the FASB issued ASU 2015-02, Consolidation. ASU 2015-02 makes targeted amendments to the current consolidation accounting guidance, in response to accounting complexity concerns. The guidance simplifies consolidation accounting by reducing the number of approaches to consolidation. The updated guidance is effective for annual and interim reporting periods beginning after December 15, 2015. The adoption of this guidance is not expected to have a material effect on the Company’s financial condition or results of operations, but will result in additional disclosures. In May 2015, the FASB issued ASU 2015-09, Disclosures about Short-Duration Contracts. ASU 2015-09 requires companies that issue short duration insurance contracts to disclose additional information, including: (i) incurred and paid claims development tables; (ii) frequency and severity of claims; and (iii) information about material changes in judgments made in calculating the liability for unpaid claim adjustment expenses, including reasons for the change and the effects on the financial statements. ASU 2015-09 is effective for annual periods beginning after December 15, 2015, and interim periods within annual periods beginning after December 15, 2016. The amendments in ASU 2015-09 should be applied retrospectively by providing comparative disclosures for each period presented, except for those requirements that apply only to the current period. As the requirements of this literature are disclosure only, the adoption of this guidance will not impact our financial condition or results of operations. In January 2016, the FASB issued ASU 2016-01, Financial Instruments. ASU 2016-01 amends the accounting guidance for financial instruments to require all equity investments to be measured at fair value with changes in the fair value recognized through net income (other than those accounted for under equity method of accounting or those that result in consolidation of the investee). The updated guidance is effective for public business entities for annual reporting periods beginning after December 15, 2017 and interim periods within those years. The adoption of this guidance is not expected to have a material effect on the Company’s financial condition upon adoption, but will impact results of operations after adoption of this guidance as unrealized gains and losses on equity securities will no longer be reported directly in AOCI, but will instead be reported in net income. All other recently issued but not yet effective accounting and reporting standards are either not applicable to the Company or are not expected to have a material impact on the Company.

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Schedule of estimated fair value of net assets acquired and liabilities assumed	(In thousands) 2014 Cash and cash equivalents $ 17,457 Real estate, furniture and equipment 669 Goodwill and other intangibles assets 79,646 Premium and service fee receivable 24,432 Other assets 2,590 Total assets acquired 124,794 Deferred federal income tax (7,107 ) Debt — Other liabilities assumed (34,809 ) Net assets acquired $ 82,878

Consolidated Statement of Com43

Consolidated Statement of Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Components of Changes in Accumulated Other Comprehensive Income (Loss) (AOCI)	The following table presents the components of the changes in accumulated other comprehensive income (loss) (AOCI) as of and for the year ended December 31, 2015 : (In thousands) Unrealized investment gains (losses) Currency translation adjustments Net pension asset Accumulated other comprehensive income (loss) Changes in AOCI Beginning of period $ 306,199 $ (122,649 ) $ — $ 183,550 Other comprehensive income (loss) before reclassifications (119,994 ) (124,744 ) — (244,738 ) Amounts reclassified from AOCI (5,548 ) — — (5,548 ) Other comprehensive income (loss) (125,542 ) (124,744 ) — (250,286 ) Unrealized investment gain related to non-controlling interest 38 — — 38 Ending balance $ 180,695 $ (247,393 ) $ — $ (66,698 ) Amounts reclassified from AOCI Pre-tax $ (8,535 ) (1) $ — $ — $ (8,535 ) Tax effect 2,987 (2) — — 2,987 After-tax amounts reclassified $ (5,548 ) $ — $ — $ (5,548 ) Other comprehensive income (loss) Pre-tax $ (192,186 ) $ (124,744 ) $ — $ (316,930 ) Tax effect 66,644 — — 66,644 Other comprehensive income (loss) $ (125,542 ) $ (124,744 ) $ — $ (250,286 ) The following table presents the components of the changes in accumulated other comprehensive income (loss) (AOCI) as of and for the year ended December 31, 2014 : (In thousands) Unrealized investment gains (losses) Currency translation adjustments Net pension asset Accumulated other comprehensive income (loss) Changes in AOCI Beginning of period $ 256,566 $ (60,524 ) $ (6,651 ) $ 189,391 Other comprehensive income (loss) before reclassifications 98,294 (62,125 ) — 36,169 Amounts reclassified from AOCI (48,628 ) — 6,651 (41,977 ) Other comprehensive income (loss) 49,666 (62,125 ) 6,651 (5,808 ) Unrealized investment gain related to non-controlling interest (33 ) — — (33 ) Ending balance $ 306,199 $ (122,649 ) $ — $ 183,550 Amounts reclassified from AOCI Pre-tax $ (74,812 ) (1) $ — $ 10,232 (3) $ (64,580 ) Tax effect 26,184 (2) — (3,581 ) (2) 22,603 After-tax amounts reclassified $ (48,628 ) $ — $ 6,651 $ (41,977 ) Other comprehensive income (loss) Pre-tax $ 72,889 $ (62,125 ) $ 10,232 $ 20,996 Tax effect (23,223 ) — (3,581 ) (26,804 ) Other comprehensive income (loss) $ 49,666 $ (62,125 ) $ 6,651 $ (5,808 ) _______________ (1) Net investment gains in the consolidated statements of income. (2) Income tax expense in the consolidated statements of income. (3) Other operating costs and expenses in the consolidated statements of income.

Investments In Fixed Maturity44

Investments In Fixed Maturity Securities (Tables) - Debt Securities	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2013
Schedule of Marketable Securities [Line Items]
Investments In Fixed Maturity Securities	At December 31, 2015 and 2014 , investments in fixed maturity securities were as follows: (In thousands) Amortized Gross Unrealized Fair Carrying Gains Losses December 31, 2015 Held to maturity: State and municipal $ 77,129 $ 16,246 $ — $ 93,375 $ 77,129 Residential mortgage-backed 19,138 2,207 — 21,345 19,138 Corporate — — — — — Total held to maturity 96,267 18,453 — 114,720 96,267 Available for sale: U.S. government and government agency 645,092 27,660 (2,333 ) 670,419 670,419 State and municipal: Special revenue 2,510,816 102,909 (3,737 ) 2,609,988 2,609,988 State general obligation 583,456 28,068 (2,070 ) 609,454 609,454 Pre-refunded 439,772 32,056 (31 ) 471,797 471,797 Corporate backed 388,904 14,039 (402 ) 402,541 402,541 Local general obligation 342,158 24,270 (29 ) 366,399 366,399 Total state and municipal 4,265,106 201,342 (6,269 ) 4,460,179 4,460,179 Mortgage-backed securities: Residential (1) 1,126,382 18,935 (11,180 ) 1,134,137 1,134,137 Commercial 64,975 875 (128 ) 65,722 65,722 Total mortgage-backed securities 1,191,357 19,810 (11,308 ) 1,199,859 1,199,859 Asset-backed securities 1,706,694 12,892 (14,414 ) 1,705,172 1,705,172 Corporate: Industrial 1,976,393 75,168 (30,027 ) 2,021,534 2,021,534 Financial 1,153,096 31,744 (11,819 ) 1,173,021 1,173,021 Utilities 192,857 8,321 (2,527 ) 198,651 198,651 Other 81,607 245 (20 ) 81,832 81,832 Total corporate 3,403,953 115,478 (44,393 ) 3,475,038 3,475,038 Foreign 799,839 50,310 (12,689 ) 837,460 837,460 Total available for sale 12,012,041 427,492 (91,406 ) 12,348,127 12,348,127 Total investments in fixed maturity securities $ 12,108,308 $ 445,945 $ (91,406 ) $ 12,462,847 $ 12,444,394 (In thousands) Amortized Gross Unrealized Fair Carrying Gains Losses December 31, 2014 Held to maturity: State and municipal $ 72,901 $ 17,501 $ — $ 90,402 $ 72,901 Residential mortgage-backed 23,278 2,854 — 26,132 23,278 Corporate 4,998 291 — 5,289 4,998 Total held to maturity 101,177 20,646 — 121,823 101,177 Available for sale: U.S. government and government agency 773,192 33,353 (3,157 ) 803,388 803,388 State and municipal: Special revenue 2,264,210 111,841 (2,084 ) 2,373,967 2,373,967 State general obligation 674,022 37,615 (787 ) 710,850 710,850 Pre-refunded 504,778 35,619 (289 ) 540,108 540,108 Corporate backed 413,234 18,976 (855 ) 431,355 431,355 Local general obligation 281,622 25,099 (5 ) 306,716 306,716 Total state and municipal 4,137,866 229,150 (4,020 ) 4,362,996 4,362,996 Mortgage-backed securities: Residential (1) 1,201,924 27,124 (9,449 ) 1,219,599 1,219,599 Commercial 74,479 1,610 (52 ) 76,037 76,037 Total mortgage-backed securities 1,276,403 28,734 (9,501 ) 1,295,636 1,295,636 Asset-backed securities 2,019,032 18,868 (11,974 ) 2,025,926 2,025,926 Corporate: Industrial 1,606,724 117,206 (5,131 ) 1,718,799 1,718,799 Financial 1,140,801 38,080 (7,673 ) 1,171,208 1,171,208 Utilities 184,107 12,436 (1 ) 196,542 196,542 Other 86,294 1,370 (2 ) 87,662 87,662 Total corporate 3,017,926 169,092 (12,807 ) 3,174,211 3,174,211 Foreign 897,668 62,223 (18,065 ) 941,826 941,826 Total available for sale 12,122,087 541,420 (59,524 ) 12,603,983 12,603,983 Total investments in fixed maturity securities $ 12,223,264 $ 562,066 $ (59,524 ) $ 12,725,806 $ 12,705,160 (1) Gross unrealized losses for mortgage-backed securities include $1,269,491 and $1,095,671 , as of December 31, 2015 and 2014 , respectively, related to the non-credit portion of OTTI recognized in other comprehensive income.
The Amortized Cost And Fair Value of Fixed Maturity Securities		The amortized cost and fair value of fixed maturity securities at December 31, 2015 , by contractual maturity, are shown below. Actual maturities may differ from contractual maturities because certain issuers may have the right to call or prepay obligations. (In thousands) Amortized Cost Fair Value Due in one year or less $ 711,642 $ 717,075 Due after one year through five years 4,056,450 4,185,436 Due after five years through ten years 3,653,308 3,795,614 Due after ten years 2,476,413 2,543,518 Mortgage-backed securities 1,210,495 1,221,204 Total $ 12,108,308 $ 12,462,847

Investments In Equity Securit45

Investments In Equity Securities Available For Sale (Tables)	12 Months Ended
	Dec. 31, 2015
Equity securities available for sale
Schedule of Available-for-sale Securities [Line Items]
Schedule of Investments in Equity Securities	At December 31, 2015 and 2014 , investments in equity securities available for sale were as follows: (In thousands) Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Carrying Value December 31, 2015 Common stocks $ 56,462 $ — $ (19,189 ) $ 37,273 $ 37,273 Preferred stocks 108,730 8,216 (3,353 ) 113,593 113,593 Total $ 165,192 $ 8,216 $ (22,542 ) $ 150,866 $ 150,866 December 31, 2014 Common stocks $ 69,870 $ 11,929 $ (5,453 ) $ 76,346 $ 76,346 Preferred stocks 90,425 8,385 (4,165 ) 94,645 94,645 Total $ 160,295 $ 20,314 $ (9,618 ) $ 170,991 $ 170,991

Net Investment Income (Tables)

Net Investment Income (Tables)	12 Months Ended
	Dec. 31, 2015
Net Investment Income [Abstract]
Net Investment Income	Net investment income consists of the following: (In thousands) 2015 2014 2013 Investment income earned on: Fixed maturity securities, including cash and cash equivalents and loans receivable $ 428,325 $ 439,489 $ 442,287 Equity securities available for sale 4,624 6,726 11,380 Investment funds 62,228 131,649 67,712 Arbitrage trading account 16,891 22,438 20,431 Real estate 11,294 10,228 12,498 Gross investment income 523,362 610,530 554,308 Investment expense (10,717 ) (9,645 ) (10,017 ) Net investment income $ 512,645 $ 600,885 $ 544,291

Investment Funds (Tables)

Investment Funds (Tables)	12 Months Ended
	Dec. 31, 2015
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Investment Funds	Investment funds consist of the following: Carrying Value as of December 31, Income (Losses) (In thousands) 2015 2014 2015 2014 2013 Real estate $ 580,830 $ 466,703 $ 58,032 $ 26,233 $ 9,315 Energy 93,719 152,056 (37,373 ) 12,797 29,739 Hedged equity 70,580 282,335 (2,762 ) 10,760 7,655 Other funds 424,911 310,307 44,331 81,859 21,003 Total $ 1,170,040 $ 1,211,401 $ 62,228 $ 131,649 $ 67,712 Other funds include private equity investments carried on the equity method of accounting, which includes a publicly traded common stock investment in HealthEquity, Inc. (HQY). Our ownership interest in HQY as of December 31, 2015 is approximately 21% with a fair value of $300.1 million and a carrying value of $45.4 million .

Real Estate (Tables)

Real Estate (Tables)	12 Months Ended
	Dec. 31, 2015
Real Estate [Abstract]
Schedule of real estate properties	Investment in real estate represents directly owned property held for investment, as follows: As of December 31, (In thousands) 2015 2014 Properties in operation $ 226,055 $ 196,980 Properties under development 710,312 534,632 Total $ 936,367 $ 731,612

Loans Receivable (Tables)

Loans Receivable (Tables)	12 Months Ended
	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Schedule of Loans Receivable	Loans receivable are as follows: As of December 31, (In thousands) 2015 2014 Amortized cost: Real estate loans $ 200,499 $ 243,407 Commercial loans 72,604 78,605 Total $ 273,103 $ 322,012 Fair value: Real estate loans $ 201,641 $ 245,112 Commercial loans 74,106 80,107 Total $ 275,747 $ 325,219 Valuation allowance: Specific $ — $ 115 General 2,094 2,371 Total $ 2,094 $ 2,486 For the Year Ended December 31, 2015 2014 (Decrease) increase in valuation allowance $ (392 ) $ 398

Realized And Unrealized Inves50

Realized And Unrealized Investment Gains and Losses (Tables)	12 Months Ended
	Dec. 31, 2015
Realized and Unrealized Investment Gains (Losses) [Abstract]
Realized and Unrealized Investment Gains (Losses)	Realized and unrealized investment gains and losses are as follows: (In thousands) 2015 2014 2013 Realized investment gains and losses: Fixed maturity securities: Gains $ 23,755 $ 39,113 $ 48,860 Losses (4,065 ) (4,420 ) (14,670 ) Equity securities available for sale 9,639 38,296 70,235 Investment funds 93,529 96,204 10,976 Real estate — 85,659 — Other gains 2,775 — 12,185 Net realized gains on investments sales 125,633 254,852 127,586 Net other-than-temporary impairments: Other-than-temporary impairments (33,309 ) — (6,042 ) Net other-than-temporary impairments (33,309 ) — (6,042 ) Total net investment gains 92,324 254,852 121,544 Income tax expense (32,313 ) (89,198 ) (47,426 ) After-tax realized investment gain and losses $ 60,011 $ 165,654 $ 74,118
Change In Unrealized Gains (Losses)	Change in unrealized gains and losses of available for sales securities: Fixed maturity securities $ (144,445 ) $ 155,765 $ (401,812 ) Previously impaired fixed maturity securities (174 ) 865 1,076 Equity securities available for sale (27,809 ) (69,016 ) 11,864 Investment funds (19,758 ) (14,725 ) (10,250 ) Total change in unrealized gains (192,186 ) 72,889 (399,122 ) Income tax benefit (expense) 66,644 (23,223 ) 138,058 Noncontrolling interests 38 (33 ) (28 ) After-tax change in unrealized investment gain and losses of available for sale securities $ (125,504 ) $ 49,633 $ (261,092 )

Securities In An Unrealized L51

Securities In An Unrealized Loss Position (Tables)	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Securities In An Unrealized Loss Position	The following table summarizes all securities in an unrealized loss position at December 31, 2015 and 2014 by the length of time those securities have been continuously in an unrealized loss position. Less Than 12 Months 12 Months or Greater Total (In thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses December 31, 2015 U.S. government and government agency $ 101,660 $ 487 $ 64,500 $ 1,846 $ 166,160 $ 2,333 State and municipal 501,952 4,404 106,681 1,865 608,633 6,269 Mortgage-backed securities 381,986 3,639 184,807 7,669 566,793 11,308 Asset-backed securities 1,091,078 7,703 190,467 6,711 1,281,545 14,414 Corporate 1,232,940 35,406 76,797 8,987 1,309,737 44,393 Foreign government 169,190 8,822 19,528 3,867 188,718 12,689 Fixed maturity securities 3,478,806 60,461 642,780 30,945 4,121,586 91,406 Common stocks 18,641 18,005 7,829 1,184 26,470 19,189 Preferred stocks — — 22,320 3,353 22,320 3,353 Equity securities available for sale 18,641 18,005 30,149 4,537 48,790 22,542 Total $ 3,497,447 $ 78,466 $ 672,929 $ 35,482 $ 4,170,376 $ 113,948 December 31, 2014 U.S. government and government agency $ 84,750 $ 522 $ 84,850 $ 2,635 $ 169,600 $ 3,157 State and municipal 158,594 631 150,284 3,389 308,878 4,020 Mortgage-backed securities 75,739 332 312,922 9,169 388,661 9,501 Asset-backed securities 1,186,097 6,217 30,818 5,757 1,216,915 11,974 Corporate 400,141 2,480 183,810 10,327 583,951 12,807 Foreign government 76,471 3,907 85,025 14,158 161,496 18,065 Fixed maturity securities 1,981,792 14,089 847,709 45,435 2,829,501 59,524 Common stocks 15,929 5,453 — — 15,929 5,453 Preferred stocks 27,126 1,139 22,648 3,026 49,774 4,165 Equity securities available for sale 43,055 6,592 22,648 3,026 65,703 9,618 Total $ 2,024,847 $ 20,681 $ 870,357 $ 48,461 $ 2,895,204 $ 69,142
Non-Investment Grade Fixed Maturity Securities	A summary of the Company’s non-investment grade fixed maturity securities that were in an unrealized loss position at December 31, 2015 is presented in the table below: (Dollars in thousands) Number of Securities Aggregate Fair Value Gross Unrealized Loss Mortgage-backed securities 8 $ 23,370 $ 1,790 Asset-backed securities 7 19,535 264 Corporate 12 128,716 6,717 Foreign government 1 13,956 3,766 Total 28 $ 185,577 $ 12,537

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Assets And Liabilities Measured At Fair value, On A Recurring Basis	The following tables present the assets and liabilities measured at fair value on a recurring basis as of December 31, 2015 and 2014 by level: (In thousands) Total Level 1 Level 2 Level 3 December 31, 2015 Assets: Fixed maturity securities available for sale: U.S. government and government agency $ 670,419 $ — $ 670,419 $ — State and municipal 4,460,179 — 4,460,179 — Mortgage-backed securities 1,199,859 — 1,199,859 — Asset-backed securities 1,705,172 — 1,704,973 199 Corporate 3,475,038 — 3,474,884 154 Foreign government 837,460 — 837,460 — Total fixed maturity securities available for sale 12,348,127 — 12,347,774 353 Equity securities available for sale: Common stocks 37,273 29,444 — 7,829 Preferred stocks 113,593 — 109,969 3,624 Total equity securities available for sale 150,866 29,444 109,969 11,453 Arbitrage trading account 376,697 256,914 119,607 176 Total $ 12,875,690 $ 286,358 $ 12,577,350 $ 11,982 Liabilities: Trading account securities sold but not yet purchased $ 37,035 $ 35,559 $ 1,476 $ — December 31, 2014 Assets: Fixed maturity securities available for sale: U.S. government and government agency $ 803,388 $ — $ 803,388 $ — State and municipal 4,362,996 — 4,362,996 — Mortgage-backed securities 1,295,636 — 1,295,636 — Asset-backed securities 2,025,926 — 2,005,315 20,611 Corporate 3,174,211 — 3,174,057 154 Foreign government 941,826 — 941,826 — Total fixed maturity securities available for sale 12,603,983 — 12,583,218 20,765 Equity securities available for sale: Common stocks 76,346 65,605 — 10,741 Preferred stocks 94,645 — 90,932 3,713 Total equity securities available for sale 170,991 65,605 90,932 14,454 Arbitrage trading account 450,648 295,047 154,881 720 Total $ 13,225,622 $ 360,652 $ 12,829,031 $ 35,939 Liabilities: Trading account securities sold but not yet purchased $ 106,079 $ 106,074 $ 5 $ —
Summarize Changes In Level 3 Assets and Liabilities	The following tables summarize changes in Level 3 assets and liabilities for the years ended December 31, 2015 and 2014 : Gains (Losses) Included in: (In thousands) Beginning Balance Earnings (Losses) Other Comprehensive Income (Losses) Impairments Purchases Sales Paydowns/Maturities Transfers In / Out Ending Balance Year ended December 31, 2015 Assets: Fixed maturity securities available for sale: Asset-backed securities $ 20,611 $ 19 $ 191 $ — $ — $ — $ (1,820 ) $ (18,802 ) $ 199 Corporate 154 — — — — — — — 154 Total 20,765 19 191 — — — (1,820 ) (18,802 ) 353 Equity securities available for sale: Common stocks 10,741 — (273 ) (2,331 ) — (308 ) — — 7,829 Preferred stocks 3,713 (89 ) — — — — — — 3,624 Total 14,454 (89 ) (273 ) (2,331 ) — (308 ) — — 11,453 Arbitrage trading account 720 (799 ) — — 72,640 (71,921 ) — (464 ) 176 Total $ 35,939 $ (869 ) $ (82 ) $ (2,331 ) $ 72,640 $ (72,229 ) $ (1,820 ) $ (19,266 ) $ 11,982 Liabilities: Trading account securities sold but not yet purchased $ — $ — $ — $ — $ — $ — $ — $ — $ — Year ended December 31, 2014 Assets: Fixed maturity securities available for sale: Asset-backed securities $ 42,710 $ 47 $ (3,711 ) $ — $ 238 $ (15,244 ) $ (3,429 ) $ — $ 20,611 Corporate $ 154 $ — $ — $ — $ — $ — $ — $ — $ 154 Total 42,864 47 (3,711 ) — 238 (15,244 ) (3,429 ) — 20,765 Equity securities available for sale: Common stocks 1,238 — (911 ) — 11,343 (929 ) — — 10,741 Preferred stocks 3,752 (17 ) — — 3,430 (3,452 ) — — 3,713 Total 4,990 (17 ) (911 ) — 14,773 (4,381 ) — — 14,454 Arbitrage trading account 1,780 2,274 — — 4,942 (14,073 ) — 5,797 720 Total $ 49,634 $ 2,304 $ (4,622 ) $ — $ 19,953 $ (33,698 ) $ (3,429 ) $ 5,797 $ 35,939 Liabilities: Trading account securities sold but not yet purchased $ — $ (20 ) $ — $ — $ 31 $ (11 ) $ — $ — $ —

Reserves For Losses And Loss 53

Reserves For Losses And Loss Expenses (Tables)	12 Months Ended
	Dec. 31, 2014
Insurance [Abstract]
Schedule of Liability for Unpaid Claims and Claims Adjustment Expense	The table below provides a reconciliation of the beginning and ending reserve balances: (In thousands) 2015 2014 2013 Net reserves at beginning of year $ 8,970,641 $ 8,683,797 $ 8,411,851 Net provision for losses and loss expenses: Claims occuring during the current year(1) 3,653,561 3,495,825 3,221,393 Decrease in estimates for claims occurring in prior years(2)(3) (46,713 ) (75,764 ) (78,810 ) Loss reserve discount accretion(4) 49,422 70,506 54,441 Total 3,656,270 3,490,567 3,197,024 Net payments for claims: Current year 914,637 898,944 822,787 Prior year 2,342,378 2,216,283 2,055,284 Total 3,257,015 3,115,227 2,878,071 Foreign currency translation (125,024 ) (88,496 ) (47,007 ) Net reserves at end of year 9,244,872 8,970,641 8,683,797 Ceded reserve at end of year 1,424,278 1,399,060 1,397,144 Gross reserves at end of year $ 10,669,150 $ 10,369,701 $ 10,080,941 _______________________________________ (1) Claims occurring during the current year are net of loss reserve discounts of $20,357,000 , $21,306,000 , and $22,680,000 in 2015 , 2014 and 2013 , respectively. (2) The decrease in estimates for claims occurring in prior years is net of loss reserve discount. On an undiscounted basis, the estimates for claims occurring in prior years decreased by $64,971,000 , $116,866,000 and $77,430,000 in 2015 , 2014 and 2013 , respectively. (3) For certain retrospectively rated insurance polices and reinsurance agreements, reserve development is offset by additional or return premiums. Favorable reserve development, net of additional and return premiums, was $63 million , $85 million and $98 million in 2015 , 2014 and 2013 , respectively. (4) In 2014, the Company entered into a commutation agreement that resulted in a reduction in prior year workers' compensation reserves of $ 30 million on an undiscounted basis and $12 million on a discounted basis.

Reinsurance (Tables)

Reinsurance (Tables)	12 Months Ended
	Dec. 31, 2015
Reinsurance Disclosures [Abstract]
Reinsurance Financial Information	The following is a summary of reinsurance financial information: (In thousands) 2015 2014 2013 Written premiums: Direct $ 6,412,533 $ 6,185,242 $ 5,626,172 Assumed 837,460 877,596 884,919 Ceded (1,060,478 ) (1,065,891 ) (1,010,918 ) Total net written premiums $ 6,189,515 $ 5,996,947 $ 5,500,173 Earned premiums: Direct $ 6,245,714 $ 5,889,021 $ 5,328,955 Assumed 845,735 886,063 857,119 Ceded (1,050,840 ) (1,030,666 ) (959,537 ) Total net earned premiums $ 6,040,609 $ 5,744,418 $ 5,226,537 Ceded losses and loss expenses incurred $ 501,999 $ 475,802 $ 556,108 Ceded commission earned $ 129,766 $ 160,215 $ 137,449
Schedule of Ceded Credit Risk by Reinsurer	The following table presents the amounts due from reinsurers as of December 31, 2015 : (In thousands) Allegany Group $ 138,163 Munich Re 121,661 Swiss Re 115,215 Lloyd’s of London 92,635 Axis Capital 69,840 Partner Re 65,793 Hannover Re Group 48,675 Everest Re 47,945 Berkshire Hathaway 47,309 Chubb Limited (1) 45,645 Arch Capital Group 23,273 Other reinsurers less than $20,000 213,169 Subtotal 1,029,323 Residual market pools 503,506 Total $ 1,532,829 (1) Includes the aggregate recoverables from Ace Group and Chubb Group.

Indebtedness (Tables)

Indebtedness (Tables)	12 Months Ended
	Dec. 31, 2014
Senior Notes and Other Debt
Debt Instrument [Line Items]
Schedule of Debt	Indebtedness consisted of the following as of December 31, 2015 (the difference between the face value and the carrying value is unamortized discount): (In thousands) Interest Rate Face Value 2015 Carrying Value 2014 Carrying Value Senior notes due on: May 15, 2015 5.6% $ — $ — $ 199,930 August 15, 2019 6.15% 150,000 149,484 149,342 September 15, 2019 7.375% 300,000 299,054 298,800 September 15, 2020 5.375% 300,000 298,411 298,074 January 1, 2022 8.7% 76,503 76,097 76,048 March 15, 2022 4.625% 350,000 347,417 346,999 February 15, 2037 6.25% 250,000 247,676 247,566 August 1, 2044 4.75% 350,000 344,730 344,545 Subsidiary debt (1) Various 81,752 81,752 154,223 Total senior notes and other debt $ 1,858,255 $ 1,844,621 $ 2,115,527 Subordinated debentures, due on April, 30, 2053 5.625% $ 350,000 $ 340,320 $ 340,060 _____________ (1) Subsidiary debt is due as follows: $43 million in 2016 , $37 million in 2017 and $2 million thereafter.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	Income tax expense consists of: (In thousands) Current Expense Deferred Expense Total December 31, 2015 Domestic $ 179,150 $ 31,145 $ 210,295 Foreign (2,318 ) 19,946 17,628 Total expense $ 176,832 $ 51,091 $ 227,923 December 31, 2014 Domestic $ 258,337 $ 28,029 $ 286,366 Foreign 12,969 3,258 16,227 Total expense $ 271,306 $ 31,287 $ 302,593 December 31, 2013 Domestic $ 116,802 $ 47,370 $ 164,172 Foreign 22,362 7,053 29,415 Total expense $ 139,164 $ 54,423 $ 193,587
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of the income tax expense and the amounts computed by applying the Federal and foreign income tax rate of 35% to pre-tax income are as follows: (In thousands) 2015 2014 2013 Computed “expected” tax expense $ 256,210 $ 333,269 $ 244,611 Tax-exempt investment income (39,283 ) (38,757 ) (40,679 ) Change in valuation allowance 2,702 1,335 — Impact of foreign tax rates 4,447 6,239 (4,851 ) State and local taxes 940 2,375 2,906 Other, net 2,907 (1,868 ) (8,400 ) Total expense $ 227,923 $ 302,593 $ 193,587
Schedule of Deferred Tax Assets and Liabilities	(In thousands) 2015 2014 2013 Computed “expected” tax expense $ 256,210 $ 333,269 $ 244,611 Tax-exempt investment income (39,283 ) (38,757 ) (40,679 ) Change in valuation allowance 2,702 1,335 — Impact of foreign tax rates 4,447 6,239 (4,851 ) State and local taxes 940 2,375 2,906 Other, net 2,907 (1,868 ) (8,400 ) Total expense $ 227,923 $ 302,593 $ 193,587 At December 31, 2015 and 2014 , the tax effects of differences that give rise to significant portions of the deferred tax asset and deferred tax liability are as follows: (In thousands) 2015 2014 Deferred tax asset: Loss reserve discounting $ 100,806 $ 77,216 Unearned premiums 176,465 165,075 Other-than-temporary impairments 26,509 45,367 Restricted stock units 62,442 60,061 Other 89,761 101,131 Gross deferred tax asset 455,983 448,850 Less valuation allowance (4,037 ) (1,335 ) Deferred tax asset 451,946 447,515 Deferred tax liability: Amortization of intangibles 20,316 22,747 Deferred policy acquisition costs 162,344 152,001 Unrealized investment gains 115,499 175,111 Other 160,598 135,108 Deferred tax liability 458,757 484,967 Net deferred tax asset (liability) $ (6,811 ) $ (37,452 )

Dividends From Subsidiaries A57

Dividends From Subsidiaries And Statutory Financial Information (Tables)	12 Months Ended
	Dec. 31, 2015
Insurance [Abstract]
Schedule of Combined Net Income and Policyholders' Surplus in Accordance with Statutory Accounting Practices	BIC’s combined net income and statutory capital and surplus, as determined in accordance with statutory accounting practices (SAP), are as follows: (In thousands) 2015 2014 2013 Net income $ 813,303 $ 757,010 $ 468,850 Statutory capital and surplus $ 5,296,435 $ 5,438,063 $ 4,908,010

Common Stockholders' Equity (Ta

Common Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Weighted Average Number of Common Shares Used In the Computation of Basic and Diluted Earnings per Share	The weighted average number of shares used in the computation of net income per share was as follows: 2015 2014 2013 Basic 124,040,313 127,873,708 135,304,752 Diluted 130,188,866 133,651,855 140,742,922
Schedule of Changes in Shares of Common Stock Outstanding	Changes in shares of common stock outstanding, net of treasury shares, are presented below. Shares of common stock issued and outstanding do not include shares related to unissued restricted stock units and unexercised stock options. 2015 2014 2013 Balance, beginning of year 126,748,836 132,233,167 136,017,732 Shares issued 1,061,026 332,137 139,790 Shares repurchased (4,502,025 ) (5,816,468 ) (3,924,355) Balance, end of year 123,307,837 126,748,836 132,233,167

Fair Value of Financial Instr59

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Carrying Amounts and Estimated Fair Values of Financial Insruments	The following table presents the carrying amounts and estimated fair values of the Company’s financial instruments as of December 31, 2015 and 2014 : 2015 2014 (In thousands) Carrying Value Fair Value Carrying Value Fair Value Assets: Fixed maturity securities $ 12,444,394 $ 12,462,847 $ 12,705,160 $ 12,725,806 Equity securities available for sale 150,866 150,866 170,991 170,991 Arbitrage trading account 376,697 376,697 450,648 450,648 Loans receivable 273,103 275,747 322,012 325,219 Cash and cash equivalents 763,631 763,631 674,441 674,441 Trading accounts receivable from brokers and clearing organizations 383,115 383,115 371,034 371,034 Due from broker 1,713 1,713 — — Liabilities: Due to broker — — 23,133 23,133 Trading account securities sold but not yet purchased 37,035 37,035 106,079 106,079 Subordinated debentures 340,320 355,880 340,060 332,640 Senior notes and other debt 1,844,621 2,029,572 2,115,527 2,344,292

Stock Incentive Plan (Tables)

Stock Incentive Plan (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Stock Options, Activity
Schedule of Nonvested Restricted Stock Units Activity	The following table summarizes RSU information for the three years ended December 31, 2015 : 2015 2014 2013 RSUs granted and unvested at beginning of period: 5,330,445 4,491,520 4,701,120 Granted 997,522 1,154,950 108,400 Vested (1,938,000 ) (81,500 ) (146,250 ) Canceled (231,642 ) (234,525 ) (171,750 ) RSUs granted and unvested at end of period: 4,158,325 5,330,445 4,491,520
Schedule of Share-based Compensation, Unearned Compensation Related to RSU's	The fair value of RSUs at the date of grant are recorded as unearned compensation, a component of stockholders’ equity, and expensed over the vesting period. Following is a summary of changes in unearned compensation for the three years ended December 31, 2015 : (In thousands) 2015 2014 2013 Unearned compensation at beginning of year $ 88,015 $ 73,205 $ 93,653 RSUs granted, net of cancellations 50,442 51,575 4,406 RSUs expensed (30,691 ) (27,966 ) (22,881 ) RSUs forfeitures (4,228 ) (8,799 ) (1,973 ) Unearned compensation at end of year $ 103,538 $ 88,015 $ 73,205

Compensation Plans (Tables)

Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2015
Compensation Related Costs [Abstract]
Long-Term Incentive Compensation Plan Expense	The following table summarizes the LTIP expense for each of the three years ended December 31, 2015 : (In thousands) 2015 2014 2013 2011 grant $ 7,397 $ 9,855 $ 6,939 2013 grant 7,336 9,493 7,231 2014 grant 2,935 3,663 — 2015 grant 3,205 — — Total $ 20,873 $ 23,011 $ 14,170

Supplemental Financial Statem62

Supplemental Financial Statement Information (Tables)	12 Months Ended
	Dec. 31, 2015
Other Income and Expenses [Abstract]
Schedule of Other Operating Cost and Expense, by Component	Other operating costs and expenses consist of the following: (In thousands) 2015 2014 2013 Amortization of deferred policy acquisition costs $ 1,102,492 $ 1,053,397 $ 991,070 Other underwriting expenses 903,006 843,133 780,058 Service company expenses 127,365 102,726 88,662 Net foreign currency losses (gains) 400 (27 ) (10,120 ) Other costs and expenses 156,487 158,227 151,014 Total $ 2,289,750 $ 2,157,456 $ 2,000,684

Industry Segments (Tables)

Industry Segments (Tables)	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Financial Information Of Company Operating Segments	Summary financial information about the Company’s reporting segments is presented in the following table. Income (loss) before income taxes by segment includes allocated investment income. Identifiable assets by segment are those assets used in or allocated to the operation of each segment. Revenues (In thousands) Earned Premiums Investment Income Other Total Pre-Tax Income (Loss) Net Income (Loss) December 31, 2015: Insurance-Domestic $ 4,659,359 $ 358,935 $ 96,487 $ 5,114,781 $ 724,667 $ 495,082 Insurance-International 772,141 51,522 — 823,663 51,926 37,204 Reinsurance-Global 609,109 74,226 — 683,335 94,852 66,627 Corporate, other and eliminations(1) — 27,962 464,392 492,354 (231,739 ) (155,230 ) Net investment gains — — 92,324 92,324 92,324 60,011 Consolidated $ 6,040,609 $ 512,645 $ 653,203 $ 7,206,457 $ 732,030 $ 503,694 December 31, 2014: Insurance-Domestic $ 4,271,933 $ 428,632 $ 106,853 $ 4,807,418 $ 796,309 $ 539,461 Insurance-International 802,375 55,407 — 857,782 29,779 22,182 Reinsurance-Global 670,110 88,821 — 758,931 115,677 79,720 Corporate, other and eliminations(1) — 28,025 421,920 449,945 (244,421 ) (158,133 ) Net investment gains — — 254,852 254,852 254,852 165,654 Consolidated $ 5,744,418 $ 600,885 $ 783,625 $ 7,128,928 $ 952,196 $ 648,884 December 31, 2013: Insurance-Domestic $ 3,782,416 $ 404,280 $ 107,517 $ 4,294,213 $ 648,740 $ 449,981 Insurance-International 723,151 47,039 — 770,190 56,922 40,292 Reinsurance-Global 720,970 89,090 — 810,060 110,425 78,013 Corporate, other and eliminations(1) — 3,882 408,645 412,527 (238,743 ) (142,479 ) Net investment gains — — 121,544 121,544 121,544 74,118 Consolidated $ 5,226,537 $ 544,291 $ 637,706 $ 6,408,534 $ 698,888 $ 499,925
Identifiable Assets by Segments	Identifiable Assets (In thousands) December 31, 2015 December 31, 2014 Insurance-Domestic $ 16,351,737 $ 16,065,409 Insurance-International 1,711,993 1,879,438 Reinsurance-Global 2,441,340 2,713,554 Corporate, other and eliminations(1) 1,225,897 1,058,290 Consolidated $ 21,730,967 $ 21,716,691 _______________________________________ (1) Corporate, other and eliminations represent corporate revenues and expenses and other items that are not allocated to business segments.
Net Premiums Earned By Major Line Of Business	Net premiums earned by major line of business are as follows: (In thousands) 2015 2014 2013 Insurance-Domestic Other liability $ 1,546,157 $ 1,449,425 $ 1,259,376 Workers' compensation 1,269,785 1,126,704 995,047 Short-tail lines 925,468 875,898 774,809 Commercial automobile 548,450 526,344 486,759 Professional liability 369,499 293,562 266,425 Total Insurance-Domestic 4,659,359 4,271,933 3,782,416 Insurance-International Other liability 103,974 92,411 65,528 Workers' compensation 93,728 71,997 84,637 Short-tail lines 373,415 415,123 336,814 Commercial automobile 125,628 116,369 130,020 Professional liability 75,396 106,475 106,152 Total Insurance-International 772,141 802,375 723,151 Reinsurance-Global Casualty 421,811 487,264 507,790 Property 187,298 182,846 213,180 Total Reinsurance-Global 609,109 670,110 720,970 Total $ 6,040,609 $ 5,744,418 $ 5,226,537

Quarterly Financial Informati64

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	The following is a summary of quarterly financial data: (In thousands. except per share data) 2015 Three months ended March 31 June 30 September 30 December 31 Revenues $ 1,744,679 $ 1,789,765 $ 1,860,957 $ 1,811,056 Net income 118,307 123,035 152,607 109,745 Net income per share(1) Basic 0.94 0.99 1.24 0.89 Diluted 0.89 0.95 1.18 0.85 2014 Three months ended March 31 June 30 September 30 December 31 Revenues $ 1,706,906 $ 1,796,989 $ 1,840,605 $ 1,784,428 Net income 169,673 179,961 188,539 110,711 Net income per share(1) Basic 1.31 1.41 1.48 0.87 Diluted 1.25 1.35 1.42 0.83 _______________________________________ (1) Net income per share (“EPS”) in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Thus, the sum of the four quarters EPS does not necessarily equal the full-year EPS.

Summary of Significant Accoun65

Summary of Significant Accounting Policies (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Unbilled Audit Premiums	$ 3,000,000	$ 9,000,000	$ 12,000,000
Deposit contracts, liabilities	54,000,000	68,000,000
Depreciation	45,000,000	44,000,000	38,000,000
Goodwill and intangible asset impairment	0
Indefinite-lived Intangible Assets [Line Items]
Interest payments	130,000,000	120,000,000	125,000,000
Income taxes paid	165,000,000	314,000,000	$ 186,000,000
Other Assets
Indefinite-lived Intangible Assets [Line Items]
Intangible assets, net (excluding goodwill)	$ 94,000,000	$ 96,000,000

Summary of Significant Accoun66

Summary of Significant Accounting Policies (Recent accounting change) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operating costs and expenses													$ 2,289,750	$ 2,157,456	$ 2,000,684
Income before income taxes													732,030	952,196	698,888
Federal and foreign income taxes													(227,923)	(302,593)	(193,587)
Net income	$ 109,745	$ 152,607	$ 123,035	$ 118,307	$ 110,711		$ 188,539		$ 179,961		$ 169,673		$ 503,694	$ 648,884	$ 499,925
Basic net income per share (dollars per share)	$ 0.89	$ 1.24	$ 0.99	$ 0.94	$ 0.87	[1]	$ 1.48	[1]	$ 1.41	[1]	$ 1.31	[1]	$ 4.06	$ 5.07	$ 3.69
Diluted net income per share (dollars per share)	$ 0.85	$ 1.18	$ 0.95	$ 0.89	$ 0.83	[1]	$ 1.42	[1]	$ 1.35	[1]	$ 1.25	[1]	$ 3.87	$ 4.86	$ 3.55
[1]	Net income per share (“EPS”) in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Thus, the sum of the four quarters EPS does not necessarily equal the full-year EPS.

Acquisitions (Details)

Acquisitions (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Accumulated other comprehensive income (loss)		$ (66,698)	$ 183,550
Business acquisition, cost of acquired entity, cash paid		8,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Premium and service fee receivable		153,291	150,944
Deferred federal and foreign income taxes		6,811	37,452
Proceeds from Sales of Business, Affiliate and Productive Assets			16,000
Assets of Disposal Group, Including Discontinued Operation			15,000
Disposal Group, Including Discontinued Operation, Property, Plant, and Equipment, Net			4,000
Disposal Group, Including Discontinued Operation, Goodwill			7,000
Disposal Group, Including Discontinued Operation, Other Assets			6,000
Disposal Group, Including Discontinued Operation, Liabilities of Disposal Group			2,000
Other Comprehensive Income (Loss), Net of Tax		(250,286)	(5,808)	$ (276,212)
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest		732,030	952,196	698,888
Other Cost and Expense, Operating		2,289,750	2,157,456	2,000,684
Income Tax expense		(227,923)	(302,593)	(193,587)
Net income (loss)		504,107	649,603	505,301
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax		(192,186)	72,889
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax		(124,744)	(62,125)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax		0	10,232
Other Comprehensive Income (Loss), before Tax		(316,930)	20,996
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax		66,644	(23,223)
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax		0	0
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Tax		0	(3,581)
Other Comprehensive Income (Loss), Tax		66,644	(26,804)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax		(125,542)	49,666
Net change in period		(124,744)	(62,125)	(23,848)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax		$ 0	6,651
London Acquisition, Inactive insurance Company, and Worldwide Supplier of After-market (OEM) Parts [Member]
Business Acquisition [Line Items]
Indefinite-lived Intangible Assets Acquired			10,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Cash and cash equivalents			17,457
Real estate, furniture and equipment			669
Goodwill and other intangibles assets			79,646
Premium and service fee receivable			24,432
Other assets			2,590
Total assets acquired			124,794
Deferred federal and foreign income taxes			(7,107)
Debt			0
Other liabilities assumed			(34,809)
Net assets acquired			(82,878)
Minimum | Worldwide Supplier of After-market (OEM) Parts [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		2 years
Maximum | Worldwide Supplier of After-market (OEM) Parts [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		15 years
Unrealized investment gains (losses)
Business Acquisition [Line Items]
Accumulated other comprehensive income (loss)		$ 180,695	306,199	256,566
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Other comprehensive income (loss) before reclassifications		(119,994)	98,294
Amounts reclassified from AOCI		(5,548)	(48,628)
Other Comprehensive Income (Loss), Net of Tax		(125,542)	49,666
Unrealized investment gain related to non-controlling interest		38	(33)
Currency translation adjustments
Business Acquisition [Line Items]
Accumulated other comprehensive income (loss)		(247,393)	(122,649)	(60,524)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Other comprehensive income (loss) before reclassifications		(124,744)	(62,125)
Amounts reclassified from AOCI		0	0
Other Comprehensive Income (Loss), Net of Tax		(124,744)	(62,125)
Unrealized investment gain related to non-controlling interest		0	0
Net change in period		(124,744)	(62,125)	(23,848)
Net pension asset
Business Acquisition [Line Items]
Accumulated other comprehensive income (loss)		0	0	(6,651)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Other comprehensive income (loss) before reclassifications		0	0
Amounts reclassified from AOCI		0	6,651
Other Comprehensive Income (Loss), Net of Tax		0	6,651
Unrealized investment gain related to non-controlling interest		0	0
Accumulated other comprehensive income (loss)
Business Acquisition [Line Items]
Accumulated other comprehensive income (loss)		(66,698)	183,550	$ 189,391
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Other comprehensive income (loss) before reclassifications		(244,738)	36,169
Amounts reclassified from AOCI		(5,548)	(41,977)
Other Comprehensive Income (Loss), Net of Tax		(250,286)	(5,808)
Unrealized investment gain related to non-controlling interest		38	(33)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Unrealized investment gains (losses)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Marketable Securities, Realized Gain (Loss), Excluding Other than Temporary Impairments	[1]	(8,535)	(74,812)
Income Tax expense	[2]	2,987	26,184
Net income (loss)		(5,548)	(48,628)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Currency translation adjustments
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest		0	0
Income Tax expense		0	0
Net income (loss)		0	0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net pension asset
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Other Cost and Expense, Operating	[3]	0	10,232
Income Tax expense	[2]	0	(3,581)
Net income (loss)		0	6,651
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated other comprehensive income (loss)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest		(8,535)	(64,580)
Income Tax expense		2,987	22,603
Net income (loss)		$ (5,548)	$ (41,977)
[1]	Net investment gains in the consolidated statements of income.
[2]	Income tax expense in the consolidated statements of income.
[3]	Other operating costs and expenses in the consolidated statements of income.

Consolidated Statement of Com68

Consolidated Statement of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		$ 183,550
Other comprehensive loss		(250,286)	$ (5,808)	$ (276,212)
Ending balance		(66,698)	183,550
Income before income taxes		732,030	952,196	698,888
Other operating costs and expenses		2,289,750	2,157,456	2,000,684
Federal and foreign income taxes		(227,923)	(302,593)	(193,587)
Net income before noncontrolling interests		504,107	649,603	505,301
Unrealized investment gains, before tax		(192,186)	72,889
Currency translation adjustments, before tax		(124,744)	(62,125)
Net pension asset, before tax		0	10,232
Other comprehensive income (loss), before tax		(316,930)	20,996
Unrealized investment gains, tax		66,644	(23,223)
Currency translation adjustments, tax		0	0
Net pension asset, tax		0	(3,581)
Other comprehensive income (loss), tax		66,644	(26,804)
Unrealized investment gains, net of tax		(125,542)	49,666
Change in unrealized translation adjustments		(124,744)	(62,125)	(23,848)
Net pension asset, net of tax		0	6,651
Unrealized investment gains (losses)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		306,199	256,566
Other comprehensive income (loss) before reclassifications		(119,994)	98,294
Amounts reclassified from AOCI		(5,548)	(48,628)
Other comprehensive loss		(125,542)	49,666
Unrealized investment gain related to non-controlling interest		38	(33)
Ending balance		180,695	306,199	256,566
Unrealized investment gains (losses) | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net investment gains	[1]	(8,535)	(74,812)
Federal and foreign income taxes	[2]	2,987	26,184
Net income before noncontrolling interests		(5,548)	(48,628)
Currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		(122,649)	(60,524)
Other comprehensive income (loss) before reclassifications		(124,744)	(62,125)
Amounts reclassified from AOCI		0	0
Other comprehensive loss		(124,744)	(62,125)
Unrealized investment gain related to non-controlling interest		0	0
Ending balance		(247,393)	(122,649)	(60,524)
Change in unrealized translation adjustments		(124,744)	(62,125)	(23,848)
Currency translation adjustments | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before income taxes		0	0
Federal and foreign income taxes		0	0
Net income before noncontrolling interests		0	0
Net pension asset
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		0	(6,651)
Other comprehensive income (loss) before reclassifications		0	0
Amounts reclassified from AOCI		0	6,651
Other comprehensive loss		0	6,651
Unrealized investment gain related to non-controlling interest		0	0
Ending balance		0	0	(6,651)
Net pension asset | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other operating costs and expenses	[3]	0	10,232
Federal and foreign income taxes	[2]	0	(3,581)
Net income before noncontrolling interests		0	6,651
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning of period		183,550	189,391
Other comprehensive income (loss) before reclassifications		(244,738)	36,169
Amounts reclassified from AOCI		(5,548)	(41,977)
Other comprehensive loss		(250,286)	(5,808)
Unrealized investment gain related to non-controlling interest		38	(33)
Ending balance		(66,698)	183,550	$ 189,391
Accumulated other comprehensive income (loss) | Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income before income taxes		(8,535)	(64,580)
Federal and foreign income taxes		2,987	22,603
Net income before noncontrolling interests		$ (5,548)	$ (41,977)
[1]	Net investment gains in the consolidated statements of income.
[2]	Income tax expense in the consolidated statements of income.
[3]	Other operating costs and expenses in the consolidated statements of income.

Investments in Fixed Maturity69

Investments in Fixed Maturity Securities (Investments in Fixed Maturity Securities) (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
investments with a carrying value held on deposit in custodial or trust accounts	$ 963,000,000
Total held to maturity, Amortized Cost	96,267,000	$ 101,177,000
Total held to maturity, Gross Unrealized Gains	18,453,000	20,646,000
Total held to maturity, Gross Unrealized Losses	0	0
Total held to maturity, Fair Value	114,720,000	121,823,000
Total held to maturity, Carrying Value	96,267,000	101,177,000
Total available for sale, Amortized Cost	12,012,041,000	12,122,087,000
Total available for sale, Gross Unrealized Gains	427,492,000	541,420,000
Total available for sale, Gross Unrealized Losses	(91,406,000)	(59,524,000)
Total available for sale, Fair Value	12,348,127,000	12,603,983,000
Total available for sale, Carrying Value	12,348,127,000	12,603,983,000
Total investment in fixed maturity securities, Amortized Cost	12,108,308,000	12,223,264,000
Total investments in fixed maturity securities, Gross Unrealized Gains	445,945,000	562,066,000
Total investments in fixed maturity securities, Gross Unrealized Losses	(91,406,000)	(59,524,000)
Total investments in fixed maturity securities, Fair Value	12,462,847,000	12,725,806,000
Total investments in fixed maturity securities, carrying value	12,444,394,000	12,705,160,000
Foreign Government Debt Securities [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	799,839,000	897,668,000
Total available for sale, Gross Unrealized Gains	50,310,000	62,223,000
Total available for sale, Gross Unrealized Losses	(12,689,000)	(18,065,000)
Total available for sale, Fair Value	837,460,000	941,826,000
Total available for sale, Carrying Value	837,460,000	941,826,000
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	64,975,000	74,479,000
Total available for sale, Gross Unrealized Gains	875,000	1,610,000
Total available for sale, Gross Unrealized Losses	(128,000)	(52,000)
Total available for sale, Fair Value	65,722,000	76,037,000
Total available for sale, Carrying Value	65,722,000	76,037,000
U.S. government and government agency
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	645,092,000	773,192,000
Total available for sale, Gross Unrealized Gains	27,660,000	33,353,000
Total available for sale, Gross Unrealized Losses	(2,333,000)	(3,157,000)
Total available for sale, Fair Value	670,419,000	803,388,000
Total available for sale, Carrying Value	670,419,000	803,388,000
Held to maturity:
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	4,265,106,000	4,137,866,000
Total available for sale, Gross Unrealized Gains	201,342,000	229,150,000
Total available for sale, Gross Unrealized Losses	(6,269,000)	(4,020,000)
Total available for sale, Fair Value	4,460,179,000	4,362,996,000
Total available for sale, Carrying Value	4,460,179,000	4,362,996,000
State and municipal
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Accumulated Other Comprehensive Income (Loss), Other than Temporary Impairment, Not Credit Loss, Net of Tax, Available-for-sale, Debt Securities	1,269,491	1,095,671
Total available for sale, Amortized Cost	1,126,382,000	1,201,924,000
Total available for sale, Gross Unrealized Gains	18,935,000	27,124,000
Total available for sale, Gross Unrealized Losses	(11,180,000)	(9,449,000)
Total available for sale, Fair Value	1,134,137,000	1,219,599,000
Total available for sale, Carrying Value	1,134,137,000	1,219,599,000
Residential mortgage-backed
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	3,403,953,000	3,017,926,000
Total available for sale, Gross Unrealized Gains	115,478,000	169,092,000
Total available for sale, Gross Unrealized Losses	(44,393,000)	(12,807,000)
Total available for sale, Fair Value	3,475,038,000	3,174,211,000
Total available for sale, Carrying Value	3,475,038,000	3,174,211,000
Debt Securities
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	2,510,816,000	2,264,210,000
Total available for sale, Gross Unrealized Gains	102,909,000	111,841,000
Total available for sale, Gross Unrealized Losses	(3,737,000)	(2,084,000)
Total available for sale, Fair Value	2,609,988,000	2,373,967,000
Total available for sale, Carrying Value	2,609,988,000	2,373,967,000
Debt, State Government [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	583,456,000	674,022,000
Total available for sale, Gross Unrealized Gains	28,068,000	37,615,000
Total available for sale, Gross Unrealized Losses	(2,070,000)	(787,000)
Total available for sale, Fair Value	609,454,000	710,850,000
Total available for sale, Carrying Value	609,454,000	710,850,000
Revenue Subject to Refund [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	439,772,000	504,778,000
Total available for sale, Gross Unrealized Gains	32,056,000	35,619,000
Total available for sale, Gross Unrealized Losses	(31,000)	(289,000)
Total available for sale, Fair Value	471,797,000	540,108,000
Total available for sale, Carrying Value	471,797,000	540,108,000
Corporation [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	388,904,000	413,234,000
Total available for sale, Gross Unrealized Gains	14,039,000	18,976,000
Total available for sale, Gross Unrealized Losses	(402,000)	(855,000)
Total available for sale, Fair Value	402,541,000	431,355,000
Total available for sale, Carrying Value	402,541,000	431,355,000
Collateralized Mortgage Backed Securities [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	1,191,357,000	1,276,403,000
Total available for sale, Gross Unrealized Gains	19,810,000	28,734,000
Total available for sale, Gross Unrealized Losses	(11,308,000)	(9,501,000)
Total available for sale, Fair Value	1,199,859,000	1,295,636,000
Total available for sale, Carrying Value	1,199,859,000	1,295,636,000
Asset-backed Securities [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	1,706,694,000	2,019,032,000
Total available for sale, Gross Unrealized Gains	12,892,000	18,868,000
Total available for sale, Gross Unrealized Losses	(14,414,000)	(11,974,000)
Total available for sale, Fair Value	1,705,172,000	2,025,926,000
Total available for sale, Carrying Value	1,705,172,000	2,025,926,000
Industrial Property [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	1,976,393,000	1,606,724,000
Total available for sale, Gross Unrealized Gains	75,168,000	117,206,000
Total available for sale, Gross Unrealized Losses	(30,027,000)	(5,131,000)
Total available for sale, Fair Value	2,021,534,000	1,718,799,000
Total available for sale, Carrying Value	2,021,534,000	1,718,799,000
Domestic Corporate Debt Securities [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	1,153,096,000	1,140,801,000
Total available for sale, Gross Unrealized Gains	31,744,000	38,080,000
Total available for sale, Gross Unrealized Losses	(11,819,000)	(7,673,000)
Total available for sale, Fair Value	1,173,021,000	1,171,208,000
Total available for sale, Carrying Value	1,173,021,000	1,171,208,000
Public Utility, Bonds [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	192,857,000	184,107,000
Total available for sale, Gross Unrealized Gains	8,321,000	12,436,000
Total available for sale, Gross Unrealized Losses	(2,527,000)	(1,000)
Total available for sale, Fair Value	198,651,000	196,542,000
Total available for sale, Carrying Value	198,651,000	196,542,000
Other Security Investments [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	81,607,000	86,294,000
Total available for sale, Gross Unrealized Gains	245,000	1,370,000
Total available for sale, Gross Unrealized Losses	(20,000)	(2,000)
Total available for sale, Fair Value	81,832,000	87,662,000
Total available for sale, Carrying Value	81,832,000	87,662,000
Debt, Local Government [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total available for sale, Amortized Cost	342,158,000	281,622,000
Total available for sale, Gross Unrealized Gains	24,270,000	25,099,000
Total available for sale, Gross Unrealized Losses	(29,000)	(5,000)
Total available for sale, Fair Value	366,399,000	306,716,000
Total available for sale, Carrying Value	366,399,000	306,716,000
523991 Trust, Fiduciary, and Custody Activities [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
investments with a carrying value held on deposit in custodial or trust accounts	1,201,000,000
State and municipal
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total held to maturity, Amortized Cost	19,138,000	23,278,000
Total held to maturity, Gross Unrealized Gains	2,207,000	2,854,000
Total held to maturity, Gross Unrealized Losses	0	0
Total held to maturity, Fair Value	21,345,000	26,132,000
Total held to maturity, Carrying Value	19,138,000	23,278,000
Held to maturity:
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total held to maturity, Amortized Cost	77,129,000	72,901,000
Total held to maturity, Gross Unrealized Gains	16,246,000	17,501,000
Total held to maturity, Gross Unrealized Losses	0	0
Total held to maturity, Fair Value	93,375,000	90,402,000
Total held to maturity, Carrying Value	77,129,000	72,901,000
Residential mortgage-backed
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Total held to maturity, Amortized Cost	0	4,998,000
Total held to maturity, Gross Unrealized Gains	0	291,000
Total held to maturity, Gross Unrealized Losses	0	0
Total held to maturity, Fair Value	0	5,289,000
Total held to maturity, Carrying Value	$ 0	$ 4,998,000

Investments in Fixed Maturity70

Investments in Fixed Maturity Securities (The Amortized Cost and Fair Value of Fixed Maturity Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Amortized Cost, Due in one year or less	$ 711,642
Amortized Cost, Due after one year through five years	4,056,450
Amortized Cost, Due after five years through ten years	3,653,308
Amortized Cost, Due after ten years	2,476,413
Amortized Cost, Mortgage-backed securities	1,210,495
Total investment in fixed maturity securities, Amortized Cost	12,108,308	$ 12,223,264
Fair Value, Due in one year or less	717,075
Fair Value, Due after one year through five years	4,185,436
Fair Value, Due after five years through ten years	3,795,614
Fair Value, Due after ten years	2,543,518
Fair Value, Mortgage-backed securities	1,221,204
Total investments in fixed maturity securities, Fair Value	$ 12,462,847	$ 12,725,806

Investments in Fixed Maturity71

Investments in Fixed Maturity Securities (Narrative) (Details) $ in Millions	Dec. 31, 2015USD ($)
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Held-to-maturity Securities, Restricted	$ 963
Minimum ownership of Common stockholders equity	10.00%
Insurance-related Assessments [Member]
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Held-to-maturity Securities, Restricted	$ 182
Reinsurance-Global
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items]
Held-to-maturity Securities, Restricted	41
Letters of Credit Outstanding, Amount	$ 15

Investments in Equity Securit72

Investments in Equity Securities Available for Sale (Investments in Equity Securities Available for Sale) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 165,192	$ 160,295
Gross Unrealized, Gains	8,216	20,314
Gross Unrealized, Losses	(22,542)	(9,618)
Carrying value and fair value of equity securities	150,866	170,991
Common stocks
Schedule of Available-for-sale Securities [Line Items]
Cost	56,462	69,870
Gross Unrealized, Gains	0	11,929
Gross Unrealized, Losses	(19,189)	(5,453)
Carrying value and fair value of equity securities	37,273	76,346
Preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Cost	108,730	90,425
Gross Unrealized, Gains	8,216	8,385
Gross Unrealized, Losses	(3,353)	(4,165)
Carrying value and fair value of equity securities	$ 113,593	$ 94,645

Arbitrage Trading Account (Deta

Arbitrage Trading Account (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Trading Securities and Derivative Instruments [Abstract]
Arbitrage trading account	$ 376,697	$ 450,648
Options Held | Long
Derivative [Line Items]
Other derivatives not designated as hedging instruments at fair value, net	3,000
Derivative, notional amount	52,000
Options Held | Short
Derivative [Line Items]
Other derivatives not designated as hedging instruments at fair value, net	1,000
Derivative, notional amount	$ 62,000

Net Investment Income (Net Inve

Net Investment Income (Net Investment Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Investment Income [Line Items]
Gross investment income	$ 523,362	$ 610,530	$ 554,308
Investment expense	(10,717)	(9,645)	(10,017)
Net investment income	512,645	600,885	544,291
Fixed maturity securities, including cash and cash equivalents and loans receivable
Net Investment Income [Line Items]
Gross investment income	428,325	439,489	442,287
Equity securities available for sale
Net Investment Income [Line Items]
Gross investment income	4,624	6,726	11,380
Investment funds
Net Investment Income [Line Items]
Gross investment income	62,228	131,649	67,712
Arbitrage trading account
Net Investment Income [Line Items]
Gross investment income	16,891	22,438	20,431
Real estate
Net Investment Income [Line Items]
Gross investment income	$ 11,294	$ 10,228	$ 12,498

Investment Funds (Schedule of I

Investment Funds (Schedule of Investment Funds) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	21.00%
Equity Method Investments, Fair Value Disclosure	$ 300,100
Investment funds	1,170,040	$ 1,211,401
Income (Losses)	62,228	131,649	$ 67,712
Real estate
Schedule of Equity Method Investments [Line Items]
Investment funds	580,830	466,703
Income (Losses)	58,032	26,233	9,315
Energy
Schedule of Equity Method Investments [Line Items]
Investment funds	93,719	152,056
Income (Losses)	(37,373)	12,797	29,739
Hedged equity
Schedule of Equity Method Investments [Line Items]
Investment funds	70,580	282,335
Income (Losses)	(2,762)	10,760	7,655
Other funds
Schedule of Equity Method Investments [Line Items]
Investment funds	424,911	310,307
Income (Losses)	44,331	$ 81,859	$ 21,003
Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Investment funds	$ 45,400

Real Estate (Details)

Real Estate (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Real Estate [Abstract]
Properties in operation	$ 226,055	$ 196,980
Properties under development	710,312	534,632
Total	$ 936,367	$ 731,612

Real Estate (Narrative) (Detail

Real Estate (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Real Estate [Abstract]
Accumulated depreciation and amortization on properites	$ 9,073,000	$ 1,609,000
Depreciation	7,425,000	$ 4,808,000
Lease future minimum payments 2016	13,141,756
Lease future minimum payments 2017	15,483,248
Lease future minimum payments 2018	14,623,307
Lease future minimum payments 2019	11,967,190
Lease future minimum payments 2020	9,584,128
Lease future minimum payments thereafter	$ 352,328,662

Loans Receivable (Details)

Loans Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Loans Receivable [Line Items]
Loans and Leases Receivable, Gross	$ 273,103	$ 322,012
Loans receivable	$ 275,747	325,219
Debt Instrument, Term	10 years
Total loans receivable	$ 273,103	322,012
Valuation allowance, Specific	0	115
Valuation allowance, General	2,094	2,371
Valuation allowance	2,094	2,486
Increase (decrease) in valuation allowance	(392)	398
Loans in nonaccrual status	3,100	14,200
Real Estate
Loans Receivable [Line Items]
Loans and Leases Receivable, Gross	200,499	243,407
Loans receivable	201,641	245,112
Commercial
Loans Receivable [Line Items]
Loans and Leases Receivable, Gross	72,604	78,605
Loans receivable	$ 74,106	$ 80,107

Realized and Unrealized Inves79

Realized and Unrealized Investment Gains and Losses (Realized and Unrealized Investment Gains (Losses) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	$ 33,300,000	$ 0	$ 6,000,000
Fixed maturity securities, Gains	23,755,000	39,113,000	48,860,000
Fixed maturity securities, Losses	(4,065,000)	(4,420,000)	(14,670,000)
Investment funds	93,529,000	96,204,000	10,976,000
Gain (Loss) on Sale of Properties	0	85,659,000	0
Other gains	2,775,000	0	12,185,000
Net realized gains on investments sales	125,633,000	254,852,000	127,586,000
Other-than-temporary impairments	(33,309,000)	0	(6,042,000)
Net other-than-temporary impairments	(33,309,000)	0	(6,042,000)
Equity securities available for sale	9,639,000	38,296,000	70,235,000
Net investment gains	92,324,000	254,852,000	121,544,000
Income tax expense	(32,313,000)	(89,198,000)	(47,426,000)
Total after-tax investment gains	60,011,000	165,654,000	$ 74,118,000
Fixed Income Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	9,000,000	$ 0
Equity securities available for sale
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	$ 24,300,000

Realized and Unrealized Inves80

Realized and Unrealized Investment Gains and Losses (Change in Unrealized Gains (Losses) of Available For Sales Securities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Realized and Unrealized Investment Gains Losses [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	$ 33,300	$ 0	$ 6,000
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	(192,186)	72,889	(399,122)
Income tax benefit (expense)	66,644	(23,223)	138,058
Noncontrolling interests	38	(33)	(28)
Total change in unrealized gains and losses	(125,504)	49,633	(261,092)
Debt Securities
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	(144,445)	155,765	(401,812)
Debt Securities Previously Impaired
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	(174)	865	1,076
Equity securities available for sale
Realized and Unrealized Investment Gains Losses [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	24,300
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	(27,809)	(69,016)	11,864
Investment funds
Realized and Unrealized Investment Gains Losses [Line Items]
Total change in unrealized gains (losses) before income taxes and noncontrolling interests	$ (19,758)	$ (14,725)	$ (10,250)

Securities in an Unrealized L81

Securities in an Unrealized Loss Position (Securities in an Unrealized Loss Position) (Details)	12 Months Ended
	Dec. 31, 2015USD ($)position	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	$ 33,300,000	$ 0	$ 6,000,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	3,497,447,000	2,024,847,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	78,466,000	20,681,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	672,929,000	870,357,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	35,482,000	48,461,000
Available-for-sale Securities, Fair Value	4,170,376,000	2,895,204,000
Available For Sale Securities, Gross Unrealized Losses	113,948,000	69,142,000
Fixed Income Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	9,000,000	0
U.S. government and government agency
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	101,660,000	84,750,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	487,000	522,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	64,500,000	84,850,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	1,846,000	2,635,000
Available-for-sale Securities, Fair Value	166,160,000	169,600,000
Available For Sale Securities, Gross Unrealized Losses	2,333,000	3,157,000
Held to maturity:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	501,952,000	158,594,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	4,404,000	631,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	106,681,000	150,284,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	1,865,000	3,389,000
Available-for-sale Securities, Fair Value	608,633,000	308,878,000
Available For Sale Securities, Gross Unrealized Losses	6,269,000	4,020,000
Mortgage-backed securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	381,986,000	75,739,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	3,639,000	332,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	184,807,000	312,922,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	7,669,000	9,169,000
Available-for-sale Securities, Fair Value	566,793,000	388,661,000
Available For Sale Securities, Gross Unrealized Losses	11,308,000	9,501,000
Asset-backed Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	1,091,078,000	1,186,097,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	7,703,000	6,217,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	190,467,000	30,818,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	6,711,000	5,757,000
Available-for-sale Securities, Fair Value	1,281,545,000	1,216,915,000
Available For Sale Securities, Gross Unrealized Losses	14,414,000	11,974,000
Residential mortgage-backed
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	1,232,940,000	400,141,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	35,406,000	2,480,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	76,797,000	183,810,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	8,987,000	10,327,000
Available-for-sale Securities, Fair Value	1,309,737,000	583,951,000
Available For Sale Securities, Gross Unrealized Losses	44,393,000	12,807,000
Corporate backed
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	169,190,000	76,471,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	8,822,000	3,907,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	19,528,000	85,025,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	3,867,000	14,158,000
Available-for-sale Securities, Fair Value	188,718,000	161,496,000
Available For Sale Securities, Gross Unrealized Losses	12,689,000	18,065,000
Fixed maturity securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	3,478,806,000	1,981,792,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	60,461,000	14,089,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	642,780,000	847,709,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	30,945,000	45,435,000
Available-for-sale Securities, Fair Value	4,121,586,000	2,829,501,000
Available For Sale Securities, Gross Unrealized Losses	91,406,000	59,524,000
Common stocks
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	$ 10,900,000	0
Number Of Securities | position	2
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	$ 18,641,000	15,929,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	18,005,000	5,453,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	7,829,000	0
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	1,184,000	0
Available-for-sale Securities, Fair Value	26,470,000	15,929,000
Available For Sale Securities, Gross Unrealized Losses	19,189,000	5,453,000
Preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	$ 13,400,000	0
Number Of Securities | position	1
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	$ 0	27,126,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	0	1,139,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	22,320,000	22,648,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	3,353,000	3,026,000
Available-for-sale Securities, Fair Value	22,320,000	49,774,000
Available For Sale Securities, Gross Unrealized Losses	3,353,000	4,165,000
Equity securities available for sale
Schedule of Available-for-sale Securities [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Additions, No Previous Impairment	24,300,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale Securities, Less Than 12 Months, Fair Value	18,641,000	43,055,000
Available-for-sale Securities, Less Than 12 Months, Gross Unrealized Losses	18,005,000	6,592,000
Available-for-sale Securities, 12 Months or Greater, Fair Value	30,149,000	22,648,000
Available-for-sale Securities, 12 Months or Greater, Gross Unrealized Losses	4,537,000	3,026,000
Available-for-sale Securities, Fair Value	48,790,000	65,703,000
Available For Sale Securities, Gross Unrealized Losses	$ 22,542,000	$ 9,618,000

Securities in an Unrealized L82

Securities in an Unrealized Loss Position (Non-Investment Grade Fixed Maturity Securities) (Details) $ in Thousands	Dec. 31, 2015USD ($)position	Dec. 31, 2014USD ($)
Schedule of Available-for-sale Securities [Line Items]
Aggregate Fair Value	$ 4,170,376	$ 2,895,204
Preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities | position	1
Aggregate Fair Value	$ 22,320	49,774
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Aggregate Fair Value	566,793	388,661
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Aggregate Fair Value	1,281,545	1,216,915
Residential mortgage-backed
Schedule of Available-for-sale Securities [Line Items]
Aggregate Fair Value	1,309,737	583,951
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Aggregate Fair Value	$ 4,121,586	$ 2,829,501
Unrealized Loss Less than 5 Million | Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities	8
Aggregate Fair Value	$ 23,370
Gross Unrealized Loss	$ 1,790
Unrealized Loss Less than 5 Million | Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities	7
Aggregate Fair Value	$ 19,535
Gross Unrealized Loss	$ 264
Unrealized Loss Less than 5 Million | Residential mortgage-backed
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities	12
Aggregate Fair Value	$ 128,716
Gross Unrealized Loss	$ 6,717
Unrealized Loss Less than 5 Million | State and Municipal
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities	1
Aggregate Fair Value	$ 13,956
Gross Unrealized Loss	$ 3,766
Unrealized Loss Less than 5 Million | Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Number Of Securities	28
Aggregate Fair Value	$ 185,577
Gross Unrealized Loss	$ 12,537

Securities in an Unrealized L83

Securities in an Unrealized Loss Position (Narrative) (Details) $ in Thousands	Dec. 31, 2015USD ($)position	Dec. 31, 2014USD ($)
Schedule of Available-for-sale Securities [Line Items]
Securities in continuous unrealized loss position fair value	$ 4,170,376	$ 2,895,204
Securities in continuous unrealized loss position, aggregate losses accumulated In AOCI	113,948	69,142
Loans and Leases Receivable, Other, Allowance	$ 2,000	3,000
Preferred stocks
Schedule of Available-for-sale Securities [Line Items]
Securities in unrealized loss positions | position	1
Securities in continuous unrealized loss position fair value	$ 22,320	49,774
Securities in continuous unrealized loss position, aggregate losses accumulated In AOCI	$ 3,353	4,165
Common stocks
Schedule of Available-for-sale Securities [Line Items]
Securities in unrealized loss positions | position	2
Securities in continuous unrealized loss position fair value	$ 26,470	15,929
Securities in continuous unrealized loss position, aggregate losses accumulated In AOCI	$ 19,189	$ 5,453

Fair Value Measurements (Assets

Fair Value Measurements (Assets and Liabilities Measured At Fair Value, On a Recurring Basis) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	$ 12,348,127,000	$ 12,603,983,000
Equity securities available for sale	150,866,000	170,991,000
Arbitrage trading account	376,697,000	450,648,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	11,982,000	35,939,000	$ 49,634,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(869,000)	2,304,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(82,000)	(4,622,000)
Impairment of Intangible Assets (Excluding Goodwill)	(2,331,000)	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	72,640,000	19,953,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	72,229,000	33,698,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	1,820,000	3,429,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	19,266,000	(5,797,000)
Asset-backed Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	199,000	20,611,000	42,710,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	19,000	47,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	191,000	(3,711,000)
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	238,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	(15,244,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(1,820,000)	(3,429,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(18,802,000)	0
Residential mortgage-backed | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	154,000	154,000	154,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0
Debt Securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	353,000	20,765,000	42,864,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	19,000	47,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	191,000	(3,711,000)
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	238,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	15,244,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	1,820,000	3,429,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	18,802,000	0
Common stocks | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	7,829,000	10,741,000	1,238,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(273,000)	(911,000)
Impairment of Intangible Assets (Excluding Goodwill)	(2,331,000)	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	11,343,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	308,000	929,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0
Preferred stocks | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	3,624,000	3,713,000	3,752,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(89,000)	(17,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	3,430,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	3,452,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0
Equity securities available for sale | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	11,453,000	14,454,000	4,990,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(89,000)	(17,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(273,000)	(911,000)
Impairment of Intangible Assets (Excluding Goodwill)	(2,331,000)	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	14,773,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	308,000	4,381,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0	0
Trading Assets, Excluding Debt and Equity Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	176,000	720,000	$ 1,780,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(799,000)	2,274,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	72,640,000	4,942,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	71,921,000	14,073,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(464,000)	5,797,000
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	12,348,127,000	12,603,983,000
Equity securities available for sale	150,866,000	170,991,000
Arbitrage trading account	376,697,000	450,648,000
Total assets	12,875,690,000	13,225,622,000
Securities sold but not yet purchased	37,035,000	106,079,000
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Equity securities available for sale	29,444,000	65,605,000
Arbitrage trading account	256,914,000	295,047,000
Total assets	286,358,000	360,652,000
Securities sold but not yet purchased	35,559,000	106,074,000
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	12,347,774,000	12,583,218,000
Equity securities available for sale	109,969,000	90,932,000
Arbitrage trading account	119,607,000	154,881,000
Total assets	12,577,350,000	12,829,031,000
Securities sold but not yet purchased	1,476,000	5,000
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	353,000	20,765,000
Equity securities available for sale	11,453,000	14,454,000
Arbitrage trading account	176,000	720,000
Total assets	11,982,000	35,939,000
Securities sold but not yet purchased	0	0
Recurring | Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	1,705,172,000	2,025,926,000
Recurring | Asset-backed Securities [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Asset-backed Securities [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	1,704,973,000	2,005,315,000
Recurring | Asset-backed Securities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	199,000	20,611,000
Recurring | U.S. government and government agency
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	670,419,000	803,388,000
Recurring | U.S. government and government agency | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | U.S. government and government agency | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	670,419,000	803,388,000
Recurring | U.S. government and government agency | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Held to maturity:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	4,460,179,000	4,362,996,000
Recurring | Held to maturity: | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Held to maturity: | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	4,460,179,000	4,362,996,000
Recurring | Held to maturity: | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	1,199,859,000	1,295,636,000
Recurring | Mortgage-backed securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Mortgage-backed securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	1,199,859,000	1,295,636,000
Recurring | Mortgage-backed securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Residential mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	3,475,038,000	3,174,211,000
Recurring | Residential mortgage-backed | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Residential mortgage-backed | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	3,474,884,000	3,174,057,000
Recurring | Residential mortgage-backed | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	154,000	154,000
Recurring | Corporate backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	837,460,000	941,826,000
Recurring | Corporate backed | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Corporate backed | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	837,460,000	941,826,000
Recurring | Corporate backed | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity securities available for sale	0	0
Recurring | Common stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	37,273,000	76,346,000
Recurring | Common stocks | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	29,444,000	65,605,000
Recurring | Common stocks | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	0	0
Recurring | Common stocks | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	7,829,000	10,741,000
Recurring | Preferred stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	113,593,000	94,645,000
Recurring | Preferred stocks | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	0	0
Recurring | Preferred stocks | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	109,969,000	90,932,000
Recurring | Preferred stocks | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities available for sale	$ 3,624,000	$ 3,713,000

Fair Value Measurements (Summar

Fair Value Measurements (Summarize Changes in Level 3 Assets and Liabilities) (Details) - Level 3 - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0	$ 0
Earnings	0	(20,000)
Other Comprehensive Income	0	0
Fair Value, Impairment of Intangible Assets (Excluding Goodwill)	0
Purchases	0	31,000
Sales	0	(11,000)
Paydown/Maturities	0	0
Out	0	0
Ending balance	0	0
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	35,939,000	49,634,000
Earnings	(869,000)	2,304,000
Other Comprehensive Income	(82,000)	(4,622,000)
Impairment of Intangible Assets (Excluding Goodwill)	(2,331,000)	0
Purchases	72,640,000	19,953,000
Sales	(72,229,000)	(33,698,000)
Paydowns / Maturities	(1,820,000)	(3,429,000)
Out	(19,266,000)	5,797,000
Ending Balance	11,982,000	35,939,000
Residential mortgage-backed
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	154,000	154,000
Earnings	0	0
Other Comprehensive Income	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Purchases	0	0
Sales	0	0
Paydowns / Maturities	0	0
Out	0	0
Ending Balance	154,000	154,000
Fixed maturity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	20,765,000	42,864,000
Earnings	19,000	47,000
Other Comprehensive Income	191,000	(3,711,000)
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Purchases	0	238,000
Sales	0	(15,244,000)
Paydowns / Maturities	(1,820,000)	(3,429,000)
Out	(18,802,000)	0
Ending Balance	353,000	20,765,000
Common stocks
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	10,741,000	1,238,000
Earnings	0	0
Other Comprehensive Income	(273,000)	(911,000)
Impairment of Intangible Assets (Excluding Goodwill)	(2,331,000)	0
Purchases	0	11,343,000
Sales	(308,000)	(929,000)
Paydowns / Maturities	0	0
Out	0	0
Ending Balance	7,829,000	10,741,000
Preferred stocks
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	3,713,000	3,752,000
Earnings	(89,000)	(17,000)
Other Comprehensive Income	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Purchases	0	3,430,000
Sales	0	(3,452,000)
Paydowns / Maturities	0	0
Out	0	0
Ending Balance	3,624,000	3,713,000
Equity securities available for sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	14,454,000	4,990,000
Earnings	(89,000)	(17,000)
Other Comprehensive Income	(273,000)	(911,000)
Impairment of Intangible Assets (Excluding Goodwill)	(2,331,000)	0
Purchases	0	14,773,000
Sales	(308,000)	(4,381,000)
Paydowns / Maturities	0	0
Out	0	0
Ending Balance	11,453,000	14,454,000
Trading account
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	720,000	1,780,000
Earnings	(799,000)	2,274,000
Other Comprehensive Income	0	0
Impairment of Intangible Assets (Excluding Goodwill)	0	0
Purchases	72,640,000	4,942,000
Sales	(71,921,000)	(14,073,000)
Paydowns / Maturities	0	0
Out	464,000	(5,797,000)
Ending Balance	$ 176,000	$ 720,000

Reserves For Losses And Loss 86

Reserves For Losses And Loss Expenses (Schedule of Liability for Unpaid Claims and Claims Adjustment Expense) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014		Dec. 31, 2013
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Net reserves at beginning of year		$ 8,970,641	$ 8,683,797		$ 8,411,851
Net provision for losses and loss expenses:
Claims occuring during the current year		3,653,561	3,495,825	[1]	3,221,393	[1]
Decrease in estimates for claims occurring in prior years		(46,713)	(75,764)	[2],[3]	(78,810)	[2],[3]
Loss reserve discount accretion(4)	[4]	49,422	70,506		54,441
Total		3,656,270	3,490,567		3,197,024
Net payments for claims:
Current year		914,637	898,944		822,787
Prior year		2,342,378	2,216,283		2,055,284
Total		3,257,015	3,115,227		2,878,071
Foreign currency translation		(125,024)	(88,496)		(47,007)
Net reserves at end of year		9,244,872	8,970,641		8,683,797
Ceded reserve at end of year		1,424,278	1,399,060		1,397,144
Gross reserves at end of year		10,669,150	10,369,701		10,080,941
Workers' Compensation Discount, Current Year Amount		20,357	21,306		22,680
Decrease in estimates for claims occurring in prior years, undiscounted basis		64,971	116,866		77,430
Favorable reserve development and return premiums		$ 63,000	$ 85,000		$ 98,000
[1]	Claims occurring during the current year are net of loss reserve discounts of $20,357,000, $21,306,000, and $22,680,000 in 2015, 2014 and 2013, respectively.
[2]	For certain retrospectively rated insurance polices and reinsurance agreements, reserve development is offset by additional or return premiums. Favorable reserve development, net of additional and return premiums, was $63 million, $85 million and $98 million in 2015, 2014 and 2013, respectively.
[3]	The decrease in estimates for claims occurring in prior years is net of loss reserve discount. On an undiscounted basis, the estimates for claims occurring in prior years decreased by $64,971,000, $116,866,000 and $77,430,000 in 2015, 2014 and 2013, respectively.
[4]	In 2014, the Company entered into a commutation agreement that resulted in a reduction in prior year workers' compensation reserves of $30 million on an undiscounted basis and $12 million on a discounted basis.

Reserves For Losses And Loss 87

Reserves For Losses And Loss Expenses (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reserves For Losses And Loss Expenses [Line Items]
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims, Prior Years, Reserve Development, Net of Premiums, Favorable (Unfavorable)	$ 63,000	$ 85,000	$ 98,000
Prior year	2,342,378	2,216,283	2,055,284
Favorable Reserve Development Net Of Premium Offsets	63,000	85,000	98,000
Reserve for losses and loss adjustment expenses relating to asbestos and environmental claims, net	33,000	36,000
Reserve for losses and loss adjustment expenses relating to asbestos and environmental claims, gross	51,000	56,000
Increase (decrease) in net incurred losses and loss expenses relating to asbestos and environmental claims	2,000	4,000	5,000
Net paid losses and loss expenses for asbestos and environmental claims	2,000	3,000	3,000
Undiscounted [Member]
Reserves For Losses And Loss Expenses [Line Items]
Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Undiscounted Basis Prior Years	30,000
Discounted [Member]
Reserves For Losses And Loss Expenses [Line Items]
Prior year	12,000
Insurance-Domestic
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets	47,000	92,000
Insurance-Domestic | Other Insurance Liabilities [Member]
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets			39,000
Insurance-Domestic | Workers' Compensation [Member]
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets			22,000
Insurance-Domestic | Property Insurance Product Line [Member]
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets			18,000
Insurance-Domestic | Other Insurance Product Line [Member]
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets			24,000
Insurance-Domestic | Commercial Automobile [Member]
Reserves For Losses And Loss Expenses [Line Items]
reserve development unfavorable			23,000
Insurance-Domestic | Products Liability
Reserves For Losses And Loss Expenses [Line Items]
reserve development unfavorable			14,000
Reinsurance-Global
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets	11,000	16,000
Reinsurance-Global | Assumed Business [Member]
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets			$ 32,000
Insurance-International
Reserves For Losses And Loss Expenses [Line Items]
Favorable Reserve Development Net Of Premium Offsets	$ 5,000
Adverse Reserve Development		$ 23,000

Reinsurance (Reinsurance Financ

Reinsurance (Reinsurance Financial Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Disclosures [Abstract]
Due from reinsurers	$ 1,532,829	$ 1,503,441
Written premiums, Direct	6,412,533	6,185,242	$ 5,626,172
Written premiums, Assumed	837,460	877,596	884,919
Written premiums, Ceded	(1,060,478)	(1,065,891)	(1,010,918)
Total net premiums written	6,189,515	5,996,947	5,500,173
Earned premiums, Direct	6,245,714	5,889,021	5,328,955
Earned premiums, Assumed	845,735	886,063	857,119
Earned premiums, Ceded	(1,050,840)	(1,030,666)	(959,537)
Net premiums earned	6,040,609	5,744,418	5,226,537
Ceded losses incurred	501,999	475,802	556,108
Uncollectible reinsurance	1,020	1,144	1,385
Fees and Commissions, Other	$ 129,766	$ 160,215	$ 137,449

Reinsurance (Schedule Of Ceded

Reinsurance (Schedule Of Ceded Credit Risk by Reinsurer) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	$ 1,532,829	$ 1,503,441
Credit Risk Reinsurers, Subtotal, Excluding Residual Market Pools [Member]
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	1,029,323
Alleghany Group
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	138,163
Munich Re
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	121,661
Swiss Re
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	115,215
Lloyds of London
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	92,635
Axis Capital
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	69,840
Partner Re
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	65,793
Hannover Re Group
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	48,675
Everest Re
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	47,945
Berkshire Hathaway
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	47,309
Chubb Ltd. [Member]
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	45,645
Arch Capital Group
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	23,273
Other Reinsurers
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	213,169
Residual Market Pools
Ceded Credit Risk [Line Items]
Ceded reserve at end of year	$ 503,506

Indebtedness (Details)

Indebtedness (Details) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Subsidiary Debt
Debt Instrument [Line Items]
Face Value		$ 81,752
Carrying Value	[1]	81,752	$ 154,223
Repayments in 2015			43,000
Repayments in 2016			37,000
Repayments thereafter			2,000
Senior Notes and Other Debt
Debt Instrument [Line Items]
Face Value		1,858,255
Carrying Value		1,844,621	$ 2,115,527
Senior Notes | Senior Notes due May 15, 2015
Debt Instrument [Line Items]
Rate			5.60%
Face Value		0
Carrying Value		0	$ 199,930
Senior Notes | Senior Notes due August 15, 2019
Debt Instrument [Line Items]
Rate			6.15%
Face Value		150,000
Carrying Value		149,484	$ 149,342
Senior Notes | Senior Notes due September 15, 2019
Debt Instrument [Line Items]
Rate			7.375%
Face Value		300,000
Carrying Value		299,054	$ 298,800
Senior Notes | Senior Notes due September 15, 2020
Debt Instrument [Line Items]
Rate			5.375%
Face Value		300,000
Carrying Value		298,411	$ 298,074
Senior Notes | Senior Notes due January 1, 2022
Debt Instrument [Line Items]
Rate			8.70%
Face Value		76,503
Carrying Value		76,097	$ 76,048
Senior Notes | Senior Notes due March 15, 2022
Debt Instrument [Line Items]
Rate			4.625%
Face Value		350,000
Carrying Value		347,417	$ 346,999
Senior Notes | Senior Notes due February 15, 2037
Debt Instrument [Line Items]
Rate			6.25%
Face Value		250,000
Carrying Value		247,676	$ 247,566
Senior Notes | Senior Notes due August 1, 2044 [Member]
Debt Instrument [Line Items]
Rate			4.75%
Face Value		350,000
Carrying Value		344,730	$ 344,545
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Face Value			350,000
Carrying Value		$ 340,320	$ 340,060
Junior Subordinated Debt [Member] | Five Point Six Two Five Percent Subordinated Debentures [Member]
Debt Instrument [Line Items]
Rate			5.625%
[1]	Subsidiary debt is due as follows: $43 million in 2016, $37 million in 2017 and $2 million thereafter.

Income Taxes (Schedule of Compo

Income Taxes (Schedule of Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Current Expense, Domestic	$ 179,150	$ 258,337	$ 116,802
Deferred Expense (Benefit), Domestic	31,145	28,029	47,370
Domestic, Total	210,295	286,366	164,172
Current Expense, Foreign	(2,318)	12,969	22,362
Deferred Expense (Benefit), Foreign	19,946	3,258	7,053
Foreign, Total	17,628	16,227	29,415
Current Expense, Total	176,832	271,306	139,164
Deferred Expense (Benefit), Total	51,091	31,287	54,423
Total expense	227,923	302,593	193,587
Income (Loss) from Continuing Operations before Income Taxes, Domestic	689,000	910,000	598,000
Income (Loss) from Continuing Operations before Income Taxes, Foreign	$ 43,000	$ 42,000	$ 101,000

Income Taxes (Schedule of Effec

Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	35.00%
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Computed “expected” tax expense	$ 256,210	$ 333,269	$ 244,611
Tax-exempt investment income	(39,283)	(38,757)	(40,679)
Change in valuation allowance	2,702	1,335	0
Impact of foreign tax rates	4,447	6,239	(4,851)
State and local taxes	940	2,375	2,906
Other, net	2,907	(1,868)	(8,400)
Total expense	$ 227,923	$ 302,593	$ 193,587

Income Taxes (Schedule of Defer

Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Deferred tax asset:
Loss reserve discounting	$ 100,806,000	$ 77,216,000
Unearned premiums	176,465,000	165,075,000
Other-than-temporary impairments	26,509,000	45,367,000
Restricted stock units	62,442,000	60,061,000
Other	89,761,000	101,131,000
Gross deferred tax asset	455,983,000	448,850,000
Less valuation allowance	(4,037,000)	(1,335,000)
Deferred tax asset	451,946,000	447,515,000
Deferred tax liability:
Amortization of intangibles	20,316,000	22,747,000
Deferred policy acquisition costs	162,344,000	152,001,000
Unrealized investment gains	115,499,000	175,111,000
Other	160,598,000	135,108,000
Deferred tax liability	458,757,000	484,967,000
Net deferred tax asset (liability)	(6,811,000)	(37,452,000)
Current Federal income taxes	55,763,000	67,623,000
Operating Loss Carryforwards [Line Items]
Taxes Payable, Current		67,623,000
Tax Credit Carryforward, Valuation Allowance	4,000,000	$ 1,300,000
Foreign Tax Authority (expiration 2031) [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 6,100,000

Dividends From Subsidiaries A94

Dividends From Subsidiaries And Statutory Financial Information (Schedule of Combined Net Income and Policyholders' Surplus in Accordance with Statutory Accounting Practices) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Insurance [Abstract]
Amount available for dividend distribution without prior approval from regulatory authorities	$ 684,000
Net income	813,303	$ 757,010	$ 468,850
Policyholders' surplus	5,296,435	$ 5,438,063	$ 4,908,010
Increase in BIC's statutory capital and surplus	294,000
Total Adjusted Capital percentage threshold		200.00%
BIC's Total Adjusted Capital balance	$ 5,000,000
BIC's Total Adjusted Capital balance as percentage of RBC Authorized Control Level	456.00%

Common Stockholders' Equity (We

Common Stockholders' Equity (Weighted Average Number of Common Shares Used In the Computation of Basic and Diluted Earnings per Share) (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity [Abstract]
Basic	124,040,313	127,873,708	135,304,752
Diluted	130,188,866	133,651,855	140,742,922

Common Stockholders' Equity (Sc

Common Stockholders' Equity (Schedule of Changes in Shares of Common Stock Outstanding) (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Common Stock Shares Outstanding [Roll Forward]
Balance, beginning of year	126,748,836	132,233,167	136,017,732
Shares issued	1,061,026	332,137	139,790
Shares repurchased	(4,502,025)	(5,816,468)	(3,924,355)
Balance, end of year	123,307,837	126,748,836	132,233,167

Fair Value of Financial Instr97

Fair Value of Financial Instruments (Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets:
Arbitrage trading account	$ 376,697	$ 450,648
Loans receivable	275,747	325,219
Due To Broker	0	23,133
Due To Broker Fair Value	0	23,133
Carrying Value
Assets:
Fixed maturity securities	12,444,394	12,705,160
Equity securities available for sale	150,866	170,991
Arbitrage trading account	376,697	450,648
Loans receivable	273,103	322,012
Cash and cash equivalents	763,631	674,441
Trading accounts receivable from brokers and clearing organizations	383,115	371,034
Due from broker	1,713	0
Liabilities:
Trading account securities sold but not yet purchased	37,035	106,079
Subordinated debentures	340,320	340,060
Senior notes and other debt	1,844,621	2,115,527
Fair Value
Assets:
Fixed maturity securities	12,462,847	12,725,806
Equity securities available for sale	150,866	170,991
Arbitrage trading account	376,697	450,648
Loans receivable	275,747	325,219
Cash and cash equivalents	763,631	674,441
Trading accounts receivable from brokers and clearing organizations	383,115	371,034
Due from broker	1,713	0
Liabilities:
Trading account securities sold but not yet purchased	37,035	106,079
Subordinated debentures	355,880	332,640
Senior notes and other debt	$ 2,029,572	$ 2,344,292

Lease Obligations (Details)

Lease Obligations (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Leases [Abstract]
Future minimum lease payment - due in 2016	$ 42,470,000
Future minimum lease payment - due in 2017	39,443,000
Future minimum lease payment - due in 2018	35,286,000
Future minimum lease payment - due in 2019	30,941,000
Future Minimum Payments, Due in 2020	28,584,000
Future minimum lease payment - due thereafter	105,825,000
Rental expense	$ 46,271,000	$ 45,198,000	$ 44,752,000

Commitments, Litigation And C99

Commitments, Litigation And Contingent Liabilities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
Commitment to Invest in Certain Investment Funds	$ 117
Commitment to Invest in Real Estate Construction Projects	$ 485

Stock Incentive Plan (Schedule

Stock Incentive Plan (Schedule of Share-based Compensation, Stock Options, Activity) (Details) - shares	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of outstanding options - vested and exercisable	3,375	3,375	1,314,057

Stock Incentive Plan (Schedu101

Stock Incentive Plan (Schedule of Nonvested Restricted Stock Units Activity) (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Compensation Arrangement with Individual, Shares Issued	4,275,474
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
RSUs granted and unvested at beginning of period:	5,330,445,000	4,491,520,000	4,701,120
Granted	997,522,000	1,154,950,000	108,400
Vested	(1,938,000,000)	(81,500,000)	(146,250)
Canceled	(231,642,000)	(234,525,000)	(171,750)
RSUs granted and unvested at end of period:	4,158,325,000	5,330,445,000	4,491,520,000

Stock Incentive Plan (Schedu102

Stock Incentive Plan (Schedule of Share-based Compensation, Unearned Compensation Related to RSU's) (Details) - Restricted Stock Units (RSUs) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Changes In Unearned Compensation [Roll Forward]
Unearned compensation at beginning of year	$ 88,015	$ 73,205	$ 93,653
RSUs granted, net of cancellations	50,442	51,575	4,406
RSUs expensed	30,691	(27,966)	(22,881)
RSUs forfeitures	4,228	(8,799)	(1,973)
Unearned compensation at end of year	$ 103,538	$ 88,015	$ 73,205

Compensation Plans (Details)

Compensation Plans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)shares	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
LTIP Expense	$ 20,873	$ 23,011	$ 14,170
Deferred Profit Sharing
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Profit Sharing Plan Minimum Contribution, Percent	5.00%
Profit Sharing Plan, Contributions Vesting Immediately, Percent	40.00%
Profit Sharing Plan, Contributions Vesting Based on Years of Service, Percent	60.00%
Profit sharing expense	$ 42,000	38,000	34,000
2011 grant
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Long-Term Incentive Compensation Plan, Number of Units Oustanding | shares	172,850
Long-Term Incentive Compensation Plan, Maximum Value	$ 43,200
Long-Term Incentive Compensation Plan, Earned	34,300
LTIP Expense	$ 7,397	9,855	6,939
2013 grant
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Long-Term Incentive Compensation Plan, Number of Units Oustanding | shares	204,500
Long-Term Incentive Compensation Plan, Maximum Value	$ 51,100
Long-Term Incentive Compensation Plan, Earned	23,800
LTIP Expense	$ 7,336	9,493	7,231
Long-term Incentive Compensation Plan, 2014 [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Long-Term Incentive Compensation Plan, Number of Units Oustanding | shares	216,750
Long-Term Incentive Compensation Plan, Maximum Value	$ 21,700
Long-Term Incentive Compensation Plan, Earned	6,600
LTIP Expense	$ 2,935	3,663	0
Long-term Incentive Compensation Plan, 2015 [Member] [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Long-Term Incentive Compensation Plan, Number of Units Oustanding | shares	213,250,000
Long-Term Incentive Compensation Plan, Maximum Value	$ 21,300
Long-Term Incentive Compensation Plan, Earned	3,200
LTIP Expense	$ 3,205	$ 0	$ 0

Retirement Benefits (Schedule o

Retirement Benefits (Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amortization of:
Total recognized in other comprehensive income	$ 0	$ (10,232)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net after tax unamortized periodic pension cost	(4,633,208)	(4,624,134)
Net pension asset
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net after tax unamortized periodic pension cost	$ 0	$ 0	$ 6,651	$ 15,351

Retirement Benefits Retirement

Retirement Benefits Retirement Benefits (narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	$ 59,400,000
Pension Expense	$ 0	$ 9,994,000	$ 13,357,000
Supplemental Benefit Agreement (SBA) [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefits Paid		$ 4,600,000	$ 300,000

Supplemental Financial State106

Supplemental Financial Statement Information (Schedule of Other Operating Cost and Expense, by Component) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Income and Expenses [Abstract]
Amortization of deferred policy acquisition costs	$ 1,102,492	$ 1,053,397	$ 991,070
Other underwriting expenses	903,006	843,133	780,058
Service company expenses	127,365	102,726	88,662
Net foreign currency losses (gains)	400	(27)	(10,120)
Other costs and expenses	156,487	158,227	151,014
Total	$ 2,289,750	$ 2,157,456	$ 2,000,684

Industry Segments (Financial In

Industry Segments (Financial Information of Company Operating Segments) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014		Dec. 31, 2013
Segment Reporting Information [Line Items]
Earned Premiums										$ 6,040,609	$ 5,744,418		$ 5,226,537
Investment Income										512,645	600,885		544,291
Other Revenues										653,203	783,625		637,706
Total revenues		$ 1,811,056	$ 1,860,957	$ 1,789,765	$ 1,744,679	$ 1,784,428	$ 1,840,605	$ 1,796,989	$ 1,706,906	7,206,457	7,128,928		6,408,534
Pre-Tax Income (Loss)										732,030	952,196		698,888
Net income to common stockholders		$ 109,745	$ 152,607	$ 123,035	$ 118,307	$ 110,711	$ 188,539	$ 179,961	$ 169,673	503,694	648,884		499,925
Net investment gains, before tax										92,324	254,852		121,544
Net investment gains, net of tax										60,011	165,654		74,118
Insurance-Domestic
Segment Reporting Information [Line Items]
Earned Premiums										4,659,359	4,271,933		3,782,416
Insurance-International
Segment Reporting Information [Line Items]
Earned Premiums										772,141	802,375		723,151
Reinsurance-Global
Segment Reporting Information [Line Items]
Earned Premiums										609,109	670,110		720,970
Net Investment Gains Segment [Member]
Segment Reporting Information [Line Items]
Earned Premiums										0	0		0
Investment Income										0	0		0
Operating Segments | Insurance-Domestic
Segment Reporting Information [Line Items]
Earned Premiums										4,659,359	4,271,933		3,782,416
Investment Income										358,935	428,632		404,280
Other Revenues										96,487	106,853		107,517
Total revenues										5,114,781	4,807,418		4,294,213
Pre-Tax Income (Loss)										724,667	796,309		648,740
Net income to common stockholders										495,082	539,461		449,981
Operating Segments | Insurance-International
Segment Reporting Information [Line Items]
Earned Premiums										772,141	802,375		723,151
Investment Income										51,522	55,407		47,039
Other Revenues										0	0		0
Total revenues										823,663	857,782		770,190
Pre-Tax Income (Loss)										51,926	29,779		56,922
Net income to common stockholders										37,204	22,182		40,292
Operating Segments | Reinsurance-Global
Segment Reporting Information [Line Items]
Earned Premiums										609,109	670,110		720,970
Investment Income										74,226	88,821		89,090
Other Revenues										0	0		0
Total revenues										683,335	758,931		810,060
Pre-Tax Income (Loss)										94,852	115,677		110,425
Net income to common stockholders										66,627	79,720		78,013
Corporate, Other and Eliminations Segment
Segment Reporting Information [Line Items]
Earned Premiums										0	0	[1]	0	[1]
Investment Income										27,962	28,025	[1]	3,882	[1]
Other Revenues										464,392	421,920	[1]	408,645	[1]
Total revenues	[1]									492,354	449,945		412,527
Pre-Tax Income (Loss)										(231,739)	(244,421)	[1]	(238,743)	[1]
Net income to common stockholders										$ (155,230)	$ (158,133)	[1]	$ (142,479)	[1]
[1]	Corporate, other and eliminations represent corporate revenues and expenses and other items that are not allocated to business segments.

Industry Segments (Identifiable

Industry Segments (Identifiable Assets by Segment) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated Assets	$ 21,730,967	$ 21,716,691
Operating Segments | Insurance-Domestic
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated Assets	16,351,737	16,065,409
Operating Segments | Insurance-International
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated Assets	1,711,993	1,879,438
Operating Segments | Reinsurance-Global
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated Assets	2,441,340	2,713,554
Corporate, Other and Eliminations Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated Assets	$ 1,225,897	$ 1,058,290	[1]
[1]	Corporate, other and eliminations represent corporate revenues and expenses and other items that are not allocated to business segments.

Industry Segments (Net Premiums

Industry Segments (Net Premiums Earned By Major Line of Business) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Net premiums earned	$ 6,040,609	$ 5,744,418	$ 5,226,537
Insurance-Domestic
Segment Reporting Information [Line Items]
Net premiums earned	4,659,359	4,271,933	3,782,416
Insurance-Domestic | Other Liability [Member]
Segment Reporting Information [Line Items]
Net premiums earned	1,546,157	1,449,425	1,259,376
Insurance-Domestic | Workers' Compensation [Member]
Segment Reporting Information [Line Items]
Net premiums earned	1,269,785	1,126,704	995,047
Insurance-Domestic | Short-tail Lines [Member]
Segment Reporting Information [Line Items]
Net premiums earned	925,468	875,898	774,809
Insurance-Domestic | Commercial Automobile [Member]
Segment Reporting Information [Line Items]
Net premiums earned	548,450	526,344	486,759
Insurance-Domestic | Professional Liability
Segment Reporting Information [Line Items]
Net premiums earned	369,499	293,562	266,425
Insurance-International
Segment Reporting Information [Line Items]
Net premiums earned	772,141	802,375	723,151
Insurance-International | Other Liability [Member]
Segment Reporting Information [Line Items]
Net premiums earned	103,974	92,411	65,528
Insurance-International | Workers' Compensation [Member]
Segment Reporting Information [Line Items]
Net premiums earned	93,728	71,997	84,637
Insurance-International | Short-tail Lines [Member]
Segment Reporting Information [Line Items]
Net premiums earned	373,415	415,123	336,814
Insurance-International | Commercial Automobile [Member]
Segment Reporting Information [Line Items]
Net premiums earned	125,628	116,369	130,020
Insurance-International | Professional Liability
Segment Reporting Information [Line Items]
Net premiums earned	75,396	106,475	106,152
Reinsurance-Global
Segment Reporting Information [Line Items]
Net premiums earned	609,109	670,110	720,970
Reinsurance-Global | Casualty [Member]
Segment Reporting Information [Line Items]
Net premiums earned	421,811	487,264	507,790
Reinsurance-Global | Property [Member]
Segment Reporting Information [Line Items]
Net premiums earned	$ 187,298	$ 182,846	$ 213,180

Quarterly Financial Informat110

Quarterly Financial Information (Unaudited) (Schedule of Quarterly Financial Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 1,811,056	$ 1,860,957	$ 1,789,765	$ 1,744,679	$ 1,784,428		$ 1,840,605		$ 1,796,989		$ 1,706,906		$ 7,206,457	$ 7,128,928	$ 6,408,534
Net income	$ 109,745	$ 152,607	$ 123,035	$ 118,307	$ 110,711		$ 188,539		$ 179,961		$ 169,673		$ 503,694	$ 648,884	$ 499,925
Net income per share
Basic (dollars per share)	$ 0.89	$ 1.24	$ 0.99	$ 0.94	$ 0.87	[1]	$ 1.48	[1]	$ 1.41	[1]	$ 1.31	[1]	$ 4.06	$ 5.07	$ 3.69
Diluted (dollars per share)	$ 0.85	$ 1.18	$ 0.95	$ 0.89	$ 0.83	[1]	$ 1.42	[1]	$ 1.35	[1]	$ 1.25	[1]	$ 3.87	$ 4.86	$ 3.55
[1]	Net income per share (“EPS”) in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Thus, the sum of the four quarters EPS does not necessarily equal the full-year EPS.

Schedule II - Condensed Fina111

Schedule II - Condensed Financial Information of Registrant (Balance Sheets (Parent Company)) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 30, 2011
Assets:
Cash and cash equivalents	$ 763,631	$ 674,441	$ 839,738	$ 905,670
Fixed maturity securities available for sale at fair value (cost $201,256 and $272,283 at December 31, 2015 and 2014, respectively)	12,444,394	12,705,160
Equity securities available for sale, at fair value (cost $3,430 in 2015 and $3,738 in 2014)	150,866	170,991
Current Federal income taxes	55,763	67,623
Property, furniture and equipment at cost, less accumulated depreciation	348,224	332,098
Other assets	442,782	369,558
Total assets	21,730,967	21,716,691
Liabilities:
Other liabilities	837,937	859,736
Deferred Federal income taxes	6,811	37,452
Subordinated debentures	340,320	340,060
Total liabilities	17,097,759	17,092,557
Stockholders' equity:
Preferred stock	0	0
Common stock	47,024	47,024
Additional paid-in capital	1,005,455	991,512
Retained earnings (including accumulated undistributed net income of subsidiaries of $4,746,934 and $4,700,821 at December 31, 2015 and 2014, respectively)	6,178,070	5,732,410
Accumulated other comprehensive income (loss)	(66,698)	183,550
Treasury stock, at cost	(2,563,605)	(2,364,551)
Total common stockholders’ equity	4,600,246	4,589,945
Total liabilities and equity	21,730,967	21,716,691
Fixed maturity securities available for sale at cost	12,012,041	12,122,087
Equity securities available for sale at cost	165,192	160,295
Parent Company
Assets:
Cash and cash equivalents	195,658	90,693	$ 17,315		$ 162,972
Fixed maturity securities available for sale at fair value (cost $201,256 and $272,283 at December 31, 2015 and 2014, respectively)	201,738	273,773
Equity securities available for sale, at fair value (cost $3,430 in 2015 and $3,738 in 2014)	3,430	3,738
Investment in subsidiaries	6,454,065	6,693,731
Deferred Federal income taxes	37,135	0
Current Federal income taxes	51,512	62,882
Property, furniture and equipment at cost, less accumulated depreciation	13,150	9,852
Other assets	6,153	6,978
Total assets	6,962,841	7,141,647
Liabilities:
Due to subsidiaries	143,669	87,540
Other liabilities	115,737	162,648
Current Federal income taxes	0
Deferred Federal income taxes		149
Subordinated debentures	340,320	340,060
Senior notes	1,762,869	1,961,305
Total liabilities	2,362,595	2,551,702
Stockholders' equity:
Preferred stock	0	0
Common stock	47,024	47,024
Additional paid-in capital	1,005,455	991,512
Retained earnings (including accumulated undistributed net income of subsidiaries of $4,746,934 and $4,700,821 at December 31, 2015 and 2014, respectively)	6,178,070	5,732,410
Accumulated other comprehensive income (loss)	(66,698)	183,550
Treasury stock, at cost	(2,563,605)	(2,364,551)
Total common stockholders’ equity	4,600,246	4,589,945
Total liabilities and equity	6,962,841	7,141,647
Fixed maturity securities available for sale at cost	201,256	272,283
Equity securities available for sale at cost	3,430	3,738
Accumulated undistributed net income of subsidiaries	$ 4,746,934	$ 4,700,821

Schedule II - Condensed Fina112

Schedule II - Condensed Financial Information of Registrant (Statements of Income (Parent Company)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Income Statements, Captions [Line Items]
Other income									$ 337	$ 1,308	$ 1,026
Total revenues	$ 1,811,056	$ 1,860,957	$ 1,789,765	$ 1,744,679	$ 1,784,428	$ 1,840,605	$ 1,796,989	$ 1,706,906	7,206,457	7,128,928	6,408,534
Operating costs and expense									6,474,427	6,176,732	5,709,646
Income before income taxes									732,030	952,196	698,888
Federal income taxes:
Net expense									(227,923)	(302,593)	(193,587)
Net income to common stockholders	$ 109,745	$ 152,607	$ 123,035	$ 118,307	$ 110,711	$ 188,539	$ 179,961	$ 169,673	503,694	648,884	499,925
Dividends from subsidiaries									642,421	503,483	269,626
Parent Company
Condensed Income Statements, Captions [Line Items]
Management fees and investment income including dividends from subsidiaries of $642,421, $503,483, and $269,626 for the years ended December 31, 2015, 2014 and 2013, respectively									655,318	515,775	277,223
Net investment gains									696	5,487	24,550
Other income									348	450	223
Total revenues									656,362	521,712	301,996
Operating costs and expense									143,391	148,288	122,562
Interest expense									128,248	125,352	120,066
Income before income taxes									384,723	248,072	59,368
Federal income taxes:
Federal income taxes provided by subsidiaries on a separate return basis									272,180	366,721	225,845
Federal income tax expense on a consolidated return basis									(199,322)	(273,310)	(154,928)
Net expense									72,858	93,411	70,917
Income before undistributed equity in net income of subsidiaries									457,581	341,483	130,285
Equity in undistributed net income of subsidiaries									46,113	307,401	369,640
Net income to common stockholders									$ 503,694	$ 648,884	$ 499,925

Schedule II - Condensed Fina113

Schedule II - Condensed Financial Information of Registrant (Statements of Cash Flows (Parent Company)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Cash Flow Statements, Captions [Line Items]
Fixed maturity securities available for sale at fair value (cost $201,256 and $272,283 at December 31, 2015 and 2014, respectively)	$ 12,444,394				$ 12,705,160				$ 12,444,394	$ 12,705,160
Cash flows from operating activities:
Net income	109,745	$ 152,607	$ 123,035	$ 118,307	110,711	$ 188,539	$ 179,961	$ 169,673	503,694	648,884	$ 499,925
Adjustments to reconcile net income to net cash from operating activities:
Net investment gains									(92,324)	(254,852)	(121,544)
Depreciation and amortization									85,139	88,836	103,090
Stock incentive plans									32,123	28,068	23,784
Change in:
Other liabilities									(63,680)	(58,254)	42,787
Net cash from operating activities									881,304	734,847	819,798
Cash from (used in) investing activities:
Proceeds from sale of fixed maturity securities									1,388,680	633,459	1,344,707
Proceeds from maturities and prepayments of fixed maturity securities									2,999,339	2,605,839	2,718,156
Proceeds from sales of equity securities									15,833	113,251	267,554
Cost of purchases of fixed maturity securities									(4,455,223)	(4,292,165)	(4,198,135)
Payments to Acquire Available-for-sale Securities, Equity									(29,526)	(31,207)	(156,557)
Payments to Acquire Businesses, Net of Cash Acquired									(7,312)	(65,421)	(56,878)
Change in balance due to security broker									(22,666)	32,617	(26,155)
Net additions to real estate, furniture & equipment									(63,562)	(41,958)	(63,150)
Net cash used in investing activities									(170,763)	(808,311)	(545,364)
Cash from (used in) financing activities:
Net proceeds from stock options exercised									0	0	53
Purchase of common treasury shares									(223,652)	(238,933)	(166,473)
Cash dividends to common stockholders									(58,034)	(181,489)	(52,717)
Net cash used in financing activities									(555,318)	(69,773)	(330,262)
Net increase (decrease) in cash and cash equivalents									89,190	(165,297)	(65,932)
Cash and cash equivalents at beginning of year				674,441				839,738	674,441	839,738	905,670
Cash and cash equivalents at end of year	763,631				674,441				763,631	674,441	839,738
Parent Company
Condensed Cash Flow Statements, Captions [Line Items]
Fixed maturity securities available for sale at fair value (cost $201,256 and $272,283 at December 31, 2015 and 2014, respectively)	201,738				273,773				201,738	273,773
Cash flows from operating activities:
Net income									503,694	648,884	499,925
Adjustments to reconcile net income to net cash from operating activities:
Net investment gains									(696)	(5,487)	(24,550)
Depreciation and amortization									2,693	2,916	10,397
Equity in undistributed earnings of subsidiaries									(46,113)	(307,401)	(369,640)
Tax payments received from subsidiaries									311,482	462,809	77,305
Federal income taxes provided by subsidiaries on a separate return basis									(272,180)	(366,721)	(225,845)
Stock incentive plans									29,725	28,068	23,784
Change in:
Federal income taxes									51,772	(15,239)	21,866
Other assets									301	(364)	(821)
Other liabilities									(92,752)	(39,780)	(15,470)
Accrued investment income									524	(820)	967
Net cash from operating activities									488,450	406,865	(2,082)
Cash from (used in) investing activities:
Proceeds from sale of fixed maturity securities									380,986	289,683	230,854
Proceeds from maturities and prepayments of fixed maturity securities									123,639	103,646	68,918
Proceeds from sales of equity securities									308	7,356	23,395
Cost of purchases of fixed maturity securities									(432,645)	(605,768)	(79,132)
Payments to Acquire Available-for-sale Securities, Equity									0	0	(4,668)
Payments to Acquire Businesses, Net of Cash Acquired									0	(82,879)	0
Investments in and advances to subsidiaries, net									30,338	34,191	(58,454)
Change in balance due to security broker									0	(2,151)	6,918
Net additions to real estate, furniture & equipment									(4,425)	(1,615)	(1,896)
Net cash used in investing activities									98,201	(257,537)	185,935
Cash from (used in) financing activities:
Net proceeds from issuance of senior notes									0	344,472	339,627
Net proceeds from stock options exercised									0	0	53
Repayment of senior notes									(200,000)	0	(450,000)
Purchase of common treasury shares									(223,652)	(238,933)	(166,473)
Cash dividends to common stockholders									(58,034)	(181,489)	(52,717)
Net cash used in financing activities									(481,686)	(75,950)	(329,510)
Net increase (decrease) in cash and cash equivalents									104,965	73,378	(145,657)
Cash and cash equivalents at beginning of year				$ 90,693				$ 17,315	90,693	17,315
Cash and cash equivalents at end of year	$ 195,658				$ 90,693				$ 195,658	$ 90,693	$ 17,315

Schedule III - Supplementary114

Schedule III - Supplementary Insurance Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Cost	$ 513,128	$ 488,525	$ 452,101
Reserve for Losses and Loss Expenses	10,669,150	10,369,701	10,080,941
Unearned Premiums	3,137,133	3,026,732	2,781,437
Net Premiums Earned	6,040,609	5,744,418	5,226,537
Net Investment Income	512,645	600,885	544,291
Loss and Loss Expenses	3,656,270	3,490,567	3,197,024
Amortization of Deferred Policy Acquisition Cost	1,102,492	1,053,397	991,070
Other Operating Cost and Expenses	1,187,258	1,104,059	1,009,614
Net Premiums Written	6,189,515	5,996,947	5,500,173
Operating Segments | Insurance-Domestic
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Cost	367,977	347,261	306,464
Reserve for Losses and Loss Expenses	8,450,190	8,000,863	7,715,124
Unearned Premiums	2,529,931	2,384,511	2,107,768
Net Premiums Earned	4,659,359	4,271,933	3,782,416
Net Investment Income	358,935	428,632	404,280
Loss and Loss Expenses	2,851,136	2,571,010	2,318,541
Amortization of Deferred Policy Acquisition Cost	760,020	710,141	651,524
Other Operating Cost and Expenses	778,957	729,958	671,096
Net Premiums Written	4,812,830	4,517,587	3,994,387
Operating Segments | Insurance-International
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Cost	62,687	60,900	60,751
Reserve for Losses and Loss Expenses	798,116	855,852	672,009
Unearned Premiums	324,530	342,746	317,691
Net Premiums Earned	772,141	802,375	723,151
Net Investment Income	51,522	55,407	47,039
Loss and Loss Expenses	449,147	503,997	429,900
Amortization of Deferred Policy Acquisition Cost	169,962	173,877	152,843
Other Operating Cost and Expenses	152,629	150,129	124,497
Net Premiums Written	778,567	828,076	756,185
Operating Segments | Reinsurance-Global
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Cost	82,464	80,364	84,886
Reserve for Losses and Loss Expenses	1,420,844	1,512,986	1,693,808
Unearned Premiums	282,672	299,475	355,978
Net Premiums Earned	609,109	670,110	720,970
Net Investment Income	74,226	88,821	89,090
Loss and Loss Expenses	355,987	415,560	448,583
Amortization of Deferred Policy Acquisition Cost	172,510	169,379	186,703
Other Operating Cost and Expenses	59,986	58,315	64,567
Net Premiums Written	598,118	651,284	749,601
Corporate and adjustments
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Cost	0	0	0
Reserve for Losses and Loss Expenses	0	0	0
Unearned Premiums	0	0	0
Net Premiums Earned	0	0	0
Net Investment Income	27,962	28,025	3,882
Loss and Loss Expenses	0	0	0
Amortization of Deferred Policy Acquisition Cost	0	0	0
Other Operating Cost and Expenses	195,686	$ 165,657	$ 149,454
Net Premiums Written	$ 0

Schedule IV - Reinsurance (Deta

Schedule IV - Reinsurance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct Amount	$ 6,412,533	$ 6,185,242	$ 5,626,172
Ceded to Other Companies	1,060,478	1,065,891	1,010,918
Assumed from Other Companies	837,460	877,596	884,919
Total net premiums written	$ 6,189,515	$ 5,996,947	$ 5,500,173
Percentage of Amount Assumed to Net	13.50%	14.60%	16.10%
Insurance-Domestic
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct Amount	$ 5,521,447	$ 5,214,849	$ 4,699,348
Ceded to Other Companies	871,358	866,092	809,368
Assumed from Other Companies	162,741	168,830	104,407
Total net premiums written	$ 4,812,830	$ 4,517,587	$ 3,994,387
Percentage of Amount Assumed to Net	3.40%	3.70%	2.60%
Insurance-International
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct Amount	$ 874,359	$ 927,799	$ 887,027
Ceded to Other Companies	144,737	156,195	142,591
Assumed from Other Companies	48,945	56,472	11,749
Total net premiums written	$ 778,567	$ 828,076	$ 756,185
Percentage of Amount Assumed to Net	6.30%	6.80%	1.60%
Reinsurance-Global
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Direct Amount	$ 16,727	$ 42,594	$ 39,797
Ceded to Other Companies	44,383	43,604	58,959
Assumed from Other Companies	625,774	652,294	768,763
Total net premiums written	$ 598,118	$ 651,284	$ 749,601
Percentage of Amount Assumed to Net	104.60%	100.20%	102.60%

Schedule V - Valuation and Q116

Schedule V - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Valuation Allowances and Reserves [Roll Forward]
Opening Balance	$ 26,411	$ 24,423	$ 30,219
Additions - Charged to Expense	8,567	7,979	3,627
Deductions - Amounts Written Off	(5,303)	(5,991)	(9,423)
Ending Balance	29,675	26,411	24,423
Premiums and fees receivable
Movement in Valuation Allowances and Reserves [Roll Forward]
Opening Balance	21,446	20,951	22,919
Additions - Charged to Expense	6,281	5,944	3,133
Deductions - Amounts Written Off	(5,203)	(5,449)	(5,101)
Ending Balance	22,524	21,446	20,951
Due from reinsurers
Movement in Valuation Allowances and Reserves [Roll Forward]
Opening Balance	1,144	1,385	1,680
Additions - Charged to Expense	(24)	301	186
Deductions - Amounts Written Off	(100)	(542)	(481)
Ending Balance	1,020	1,144	1,385
Deferred federal and foreign income taxes
Movement in Valuation Allowances and Reserves [Roll Forward]
Opening Balance	1,335	0
Additions - Charged to Expense	2,702	1,335
Deductions - Amounts Written Off	0	0
Ending Balance	4,037	1,335	0
Loan loss reserves
Movement in Valuation Allowances and Reserves [Roll Forward]
Opening Balance	2,486	2,087	5,620
Additions - Charged to Expense	(392)	399	308
Deductions - Amounts Written Off	0	0	(3,841)
Ending Balance	$ 2,094	$ 2,486	$ 2,087

Schedule VI - Supplementary 117

Schedule VI - Supplementary Information Concerning Property-Casualty Insurance Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014		Dec. 31, 2013
Supplemental Information for Property, Casualty Insurance Underwriters [Abstract]
Deferred policy acquisition costs	$ 513,128	$ 488,525		$ 452,101
Reserves for losses and loss expenses	10,669,150	10,369,701		10,080,941
Unearned premium	3,137,133	3,026,732		2,781,437
Net premiums earned	6,040,609	5,744,418		5,226,537
Net investment income	512,645	600,885		544,291
Losses and loss expenses incurred:
Current year	3,653,561	3,495,825	[1]	3,221,393	[1]
Prior years	(46,713)	(75,764)		(78,810)
Loss reserve discount accretion	49,422	70,506		54,441
Amortization of deferred policy acquisition costs	1,102,492	1,053,397		991,070
Paid losses and loss expenses	3,257,015	3,115,227		2,878,071
Net premiums written	$ 6,189,515	$ 5,996,947		$ 5,500,173
[1]	Claims occurring during the current year are net of loss reserve discounts of $20,357,000, $21,306,000, and $22,680,000 in 2015, 2014 and 2013, respectively.

Uncategorized Items - wrb-20151

Label	Element	Value
Proceeds from Divestiture of Businesses, Net of Cash Divested	us-gaap_ProceedsFromDivestitureOfBusinessesNetOfCashDivested	$ 0