Selective Insurance (SIGI) 10-Q 30 Oct 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014
Document Information [Line Items]	'
Document Type	'10-Q
Amendment Flag	'false
Document Period End Date	30-Sep-14
Document Fiscal Year Focus	'2014
Document Fiscal Period Focus	'Q3
Entity Registrant Name	'SELECTIVE INSURANCE GROUP INC
Entity Central Index Key	'0000230557
Current Fiscal Year End Date	'--12-31
Entity Filer Category	'Large Accelerated Filer
Entity Common Stock , Shares Outstanding	56,424,220

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
ASSETS	'	'
Fixed income securities, held-to-maturity – at carrying value (fair value: $354,190 – 2014; $416,981 – 2013)	$336,082	$392,879
Fixed income securities, available-for-sale – at fair value (amortized cost: $3,884,252– 2014; $3,675,977 – 2013)	3,967,638	3,715,536
Equity securities, available-for-sale – at fair value (cost: $180,419 – 2014; $155,350 – 2013)	211,266	192,771
Short-term investments (at cost which approximates fair value)	181,593	174,251
Other investments	106,548	107,875
Total investments	4,803,127	4,583,312
Cash	2,501	193
Interest and dividends due or accrued	37,563	37,382
Premiums receivable, net of allowance for uncollectible accounts of: $3,860 – 2014; $4,442 – 2013	591,686	524,870
Reinsurance recoverables, net	559,946	550,897
Prepaid reinsurance premiums	158,889	143,000
Current federal income tax	0	512
Deferred federal income tax	92,780	122,613
Property and equipment – at cost, net of accumulated depreciation and amortization of: $188,175 – 2014; $179,192 – 2013	55,532	50,834
Deferred policy acquisition costs	189,681	172,981
Goodwill	7,849	7,849
Other assets	77,865	75,727
Total assets	6,577,419	6,270,170
Liabilities And Stockholders' Equity	'	'
Reserve for loss and loss expenses	3,445,706	3,349,770
Unearned premiums	1,143,979	1,059,155
Notes payable	392,294	392,414
Current federal income tax	16,322	0
Accrued salaries and benefits	97,469	111,427
Other liabilities	214,724	203,476
Total liabilities	5,310,494	5,116,242
Stockholders' Equity:	'	'
Preferred stock of $0 par value per share: Authorized shares: 5,000,000; no shares issued or outstanding	0	0
Common stock of $2 par value per share Authorized shares: 360,000,000 Issued: 99,753,415 – 2014; 99,120,235 – 2013	199,507	198,240
Additional paid-in capital	300,425	288,182
Retained earnings	1,280,148	1,202,015
Accumulated other comprehensive income	49,125	24,851
Treasury stock - at cost (shares: 43,329,195 – 2014; 43,198,622 – 2013)	-562,280	-559,360
Total stockholders' equity	1,266,925	1,153,928
Commitments and contingencies	'	'
Total liabilities and stockholders' equity	$6,577,419	$6,270,170

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Fixed income securities, held-to-maturity, fair value	$354,190	$416,981
Fixed income securities, available-for-sale, amortized cost	3,884,252	3,675,977
Equity securities, available-for-sale, cost	180,419	155,350
Premiums receivable, allowance for uncollectible accounts	3,860	4,442
Property and equipment, accumulated depreciation and amortization	$188,175	$179,192
Preferred stock, par value per share	$0	$0
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value per share	$2	$2
Common stock, shares authorized	360,000,000	360,000,000
Common stock, shares issued	99,753,415	99,120,235
Treasury stock, shares	43,329,195	43,198,622

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenues:	'	'	'	'
Net premiums earned	$462,639	$437,568	$1,382,759	$1,284,760
Net investment income earned	34,292	32,457	106,600	99,330
Net realized gains:	'	'	'	'
Net realized investment gains	15,231	14,111	28,370	25,124
Other-than-temporary impairments	0	-680	-1,382	-3,107
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0	0	-77
Total net realized gains	15,231	13,431	26,988	21,940
Other income	3,196	3,357	14,931	9,677
Total revenues	515,358	486,813	1,531,278	1,415,707
Expenses:	'	'	'	'
Loss and loss expense incurred	270,932	283,317	889,273	832,760
Policy acquisition costs	158,101	145,314	462,540	428,570
Interest expense	5,558	5,570	16,544	16,971
Other expenses	5,441	8,127	22,990	27,852
Total expenses	440,032	442,328	1,391,347	1,306,153
Income from continuing operations, before federal income tax	75,326	44,485	139,931	109,554
Federal income tax expense:	'	'	'	'
Current	7,373	6,367	22,692	20,041
Deferred	14,791	5,465	16,762	7,433
Total federal income tax expense	22,164	11,832	39,454	27,474
Net income from continuing operations	53,162	32,653	100,477	82,080
Loss on disposal of discontinued operations, net of tax of $(538) - 2013	0	0	0	-997
Net income	$53,162	$32,653	$100,477	$81,083
Earnings per share:	'	'	'	'
Basic net income from continuing operations	$0.94	$0.59	$1.79	$1.48
Basic net loss from discontinued operations	$0	$0	$0	($0.02)
Basic net income	$0.94	$0.59	$1.79	$1.46
Diluted net income from continuing operations	$0.93	$0.57	$1.75	$1.45
Diluted net loss from discontinued operations	$0	$0	$0	($0.02)
Diluted net income	$0.93	$0.57	$1.75	$1.43
Dividends to stockholders	$0.13	$0.13	$0.39	$0.39

Consolidated_Statements_of_Inc1

Consolidated Statements of Income Parenthetical (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Tax effect of loss on disposal of discontinued operations	($538)

Consolidation_Statements_of_Co

Consolidation Statements of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net income	$53,162	$32,653	$100,477	$81,083
Unrealized holding (losses) gains arising during period	-8,988	6,383	41,767	-50,576
Non-credit portion of other-than-temporary impairments recognized in other comprehensive income	0	0	0	50
Amount reclassified into net income: Held-to-maturity securities	-243	-307	-683	-1,172
Amount reclassified into net income: Non-credit other-than-temporary impairments	780	1	1,085	9
Amount reclassified into net income: Realized gains on available for sale securities	-10,683	-8,785	-18,637	-16,107
Total unrealized (losses) gains on investment securities	-19,134	-2,708	23,532	-67,796
Net actuarial gain	0	0	0	28,600
Amount reclassified into net income: Net actuarial loss	247	513	742	2,222
Amount reclassified into net income: Prior service cost	0	0	0	6
Amount reclassified into net income: Curtailment expense	0	0	0	11
Total defined benefit pension and post-retirement plans	247	513	742	30,839
Other comprehensive (loss) income	-18,887	-2,195	24,274	-36,957
Comprehensive income	$34,275	$30,458	$124,751	$44,126

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (USD $)	Total	Common stock [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Accumulated other comprehensive income [Member]	Treasury stock [Member]
In Thousands
Beginning of year at Dec. 31, 2012	'	$196,388	$270,654	$1,125,154	$54,040	($555,644)
Dividend reinvestment plan (shares: 44,322 – 2014; 49,964 - 2013)	'	100	1,052	'	'	'
Stock purchase and compensation plans (shares: 588,858 - 2014; 712,994 - 2013)	'	1,426	12,361	'	'	'
Net income	81,083	'	'	81,083	'	'
Dividends to stockholders ($0.39 per share - 2014 and 2013)	'	'	'	-22,153	'	'
Other comprehensive income (loss)	-36,957	'	'	'	-36,957	'
Acquisition of treasury stock (shares: 130,573 - 2014; 151,555 - 2013)	'	'	'	'	'	-3,295
End of period at Sep. 30, 2013	1,124,209	197,914	284,067	1,184,084	17,083	-558,939
Beginning of year at Dec. 31, 2013	1,153,928	198,240	288,182	1,202,015	24,851	-559,360
Dividend reinvestment plan (shares: 44,322 – 2014; 49,964 - 2013)	'	89	957	'	'	'
Stock purchase and compensation plans (shares: 588,858 - 2014; 712,994 - 2013)	'	1,178	11,286	'	'	'
Net income	100,477	'	'	100,477	'	'
Dividends to stockholders ($0.39 per share - 2014 and 2013)	'	'	'	-22,344	'	'
Other comprehensive income (loss)	24,274	'	'	'	24,274	'
Acquisition of treasury stock (shares: 130,573 - 2014; 151,555 - 2013)	'	'	'	'	'	-2,920
End of period at Sep. 30, 2014	$1,266,925	$199,507	$300,425	$1,280,148	$49,125	($562,280)

Consolidated_Statements_of_Sto1

Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Dividend reinvestment plan, shares	'	'	44,322	49,964
Stock purchase and compensation plans, shares	'	'	588,858	712,994
Dividends to stockholders, per share	$0.13	$0.13	$0.39	$0.39
Acquisition of treasury stock, shares	'	'	130,573	151,555
Preferred stock, par value per share	$0	$0	$0	$0
Preferred stock, shares authorized	5,000,000	5,000,000	5,000,000	5,000,000
Preferred stock, shares issued	0	0	0	0
Series A Preferred Stock [Member]	'	'	'	'
Preferred stock, par value per share	$0	$0	$0	$0
Preferred stock, shares authorized	300,000	300,000	300,000	300,000

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flow (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Operating Activities	'	'
Net income	$100,477	$81,083
Adjustments to reconcile net income to net cash provided by operating activities	'	'
Depreciation and amortization	31,059	32,861
Sale of renewal rights	-8,000	0
Loss on disposal of discontinued operations	0	997
Stock-based compensation expense	7,421	7,428
Undistributed (gains) losses of equity method investments	-131	248
Net realized gains	-26,988	-21,940
Retirement income plan curtailment expense	0	16
Changes in assets and liabilities:	'	'
Increase in reserve for loss and loss expenses, net of reinsurance recoverables	86,887	112,876
Increase in unearned premiums, net of prepaid reinsurance	68,935	120,288
Decrease in net federal income taxes	33,596	8,990
Increase in premiums receivable	-66,816	-84,826
Increase in deferred policy acquisition costs	-16,700	-21,688
Increase in interest and dividends due or accrued	-82	-45
(Decrease) increase in accrued salaries and benefits	-13,958	8,286
(Decrease) increase in accrued insurance expenses	-12,545	6,895
Other-net	-25,036	-13,480
Net adjustments	57,642	156,906
Net cash provided by operating activities	158,119	237,989
Investing Activities	'	'
Purchase of fixed income securities, available-for-sale	-560,493	-838,634
Purchase of equity securities, available-for-sale	-185,529	-112,742
Purchase of other investments	-8,498	-7,864
Purchase of short-term investments	-1,082,192	-1,619,948
Sale of subsidiary	0	1,225
Sale of fixed income securities, available-for-sale	35,499	6,851
Sale of short-term investments	1,074,850	1,662,340
Redemption and maturities of fixed income securities, held-to-maturity	56,375	87,952
Redemption and maturities of fixed income securities, available-for-sale	336,939	413,722
Sale of equity securities, available-for-sale	186,001	109,399
Distributions from other investments	13,514	10,546
Purchase of property and equipment	-9,178	-10,493
Sale of renewal rights	8,000	0
Net cash used in investing activities	-134,712	-297,646
Financing Activities	'	'
Dividends to stockholders	-20,899	-20,532
Acquisition of treasury stock	-2,920	-3,295
Net proceeds from stock purchase and compensation plans	3,554	4,305
Proceeds from issuance of notes payable, net of debt issuance costs	0	178,435
Repayment of notes payable	0	-100,000
Excess tax benefits from share-based payment arrangements	1,024	1,479
Repayments of capital lease obligations	-1,858	-768
Net cash (used in) provided by financing activities	-21,099	59,624
Net increase (decrease) in cash	2,308	-33
Cash, beginning of year	193	210
Cash, end of period	$2,501	$177

Organization

Organization	9 Months Ended
	Sep. 30, 2014
Organization [Abstract]	'
Organization	'
	Organization
	Selective Insurance Group, Inc., through its subsidiaries, (collectively referred to as “we,” “us,” or “our”) offers standard and excess and surplus lines (“E&S”) property and casualty insurance products. Selective Insurance Group, Inc. (referred to as the “Parent”) was incorporated in New Jersey in 1977 and its main offices are located in Branchville, New Jersey. The Parent’s common stock is publicly traded on the NASDAQ Global Select Market under the symbol “SIGI.”
	We classify our business into three operating segments:
	•	Our Standard Insurance Operations segment, which is comprised of both commercial lines ("Commercial Lines") and personal lines ("Personal Lines") business, sells property and casualty insurance products and services in the standard market, including flood insurance through the National Flood Insurance Program's ("NFIP") write-your-own ("WYO") program;
	•	Our E&S Insurance Operations segment sells Commercial Lines property and casualty insurance products and services to insureds who have not obtained coverage in the standard market; and
	•	Our Investments segment, which invests the premiums collected by our Standard and E&S Insurance Operations and amounts generated through our capital management strategies, which may include the issuance of debt and equity securities.

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2014
Basis of Presentation [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	These interim unaudited consolidated financial statements (“Financial Statements”) include the accounts of the Parent and its subsidiaries, and have been prepared in conformity with: (i) U.S. generally accepted accounting principles (“GAAP”); and (ii) the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. The preparation of the Financial Statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported financial statement balances, as well as the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. All significant intercompany accounts and transactions between the Parent and its subsidiaries are eliminated in consolidation.
	Certain amounts in our prior years' Financial Statements and related notes have been reclassified to conform to the 2014 presentation. Such reclassifications had no effect on our net income, stockholders' equity, or cash flows.
	These Financial Statements reflect all adjustments that, in our opinion, are normal, recurring, and necessary for a fair presentation of our results of operations and financial condition. The Financial Statements cover the third quarters ended September 30, 2014 (“Third Quarter 2014”) and September 30, 2013 (“Third Quarter 2013”) and the nine-month periods ended September 30, 2014 ("Nine Months 2014") and September 30, 2013 ("Nine Months 2013"). The Financial Statements do not include all of the information and disclosures required by GAAP and the SEC for audited annual financial statements. Results of operations for any interim period are not necessarily indicative of results for a full year. Consequently, the Financial Statements should be read in conjunction with the consolidated financial statements contained in our Annual Report on Form 10-K for the year ended December 31, 2013 (“2013 Annual Report”) filed with the SEC.

Adoption_of_Accounting_Pronoun

Adoption of Accounting Pronouncements	9 Months Ended
	Sep. 30, 2014
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]	'
Adoption Of Accounting Pronouncements	'
	Adoption of Accounting Pronouncements
	In July 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2013-11, Income Taxes, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force) ("ASU 2013-11"). ASU 2013-11 applies to all entities with unrecognized tax benefits that also have tax loss or tax credit carryforwards in the same tax jurisdiction as of the reporting date. An unrecognized tax benefit is the difference between a tax position taken or expected to be taken in a tax return and the benefit that is more likely than not sustainable under examination. Under ASU 2013-11, an entity must net an unrecognized tax benefit, or a portion of an unrecognized tax benefit, against deferred tax assets for a net operating loss ("NOL") carryforward, a similar tax loss, or a tax credit carryforward except when:
	•	An NOL carryforward, a similar tax loss, or a tax credit carryfoward is not available as of the reporting date under the governing tax law to settle taxes that would result from the disallowance of the tax position; or
	•	The entity does not intend to use the deferred tax asset for this purpose.
	If either of these conditions exist, an entity should present an unrecognized tax benefit in the financial statements as a liability and should not net the unrecognized tax benefit with a deferred tax asset.
	ASU 2013-11 was effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this guidance did not impact our financial condition or results of operation.
	In January 2014, the FASB issued ASU 2014-01, Accounting for Investments in Qualified Affordable Housing Projects ("ASU 2014-01").  ASU 2014-01 applies to all reporting entities that invest in flow-through limited liability entities that manage or invest in affordable housing projects that qualify for a low-income housing tax credit. ASU 2014-01 permits reporting entities to make an accounting policy election to account for their investments in qualified affordable housing projects using a newly defined "proportional amortization method" if certain conditions are met. This policy election is required to be applied consistently to all qualifying investments, rather than a decision to be applied to individual investments. Under the proportional amortization method, an entity amortizes the initial cost of the investment in proportion to the tax credits and other tax benefits received, and recognizes the net investment performance in the income statement as components of income tax expense (benefit).  When a company does not make a policy election to account for investments in qualified affordable housing projects using the proportional amortization method, these investments are required to be accounted for as an equity method investment or a cost method investment.
	ASU 2014-01 is effective for public business entities for annual periods and interim periods within those annual periods, beginning after December 15, 2014, with early adoption being permitted. During Third Quarter 2014, we adopted this guidance and have made a policy election to use the proportional amortization method. The adoption of this guidance did not materially impact our financial condition or results of operation.
	Pronouncements to be effective in the future
	In June 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period (“ASU 2014-12”). ASU 2014-12 applies to all reporting entities that grant their employees share-based payments in which the terms of the award provide that a performance target that affects vesting could be achieved after the requisite service period. That is the case when an employee is eligible to retire or otherwise terminate employment before the end of the period in which a performance target could be achieved and still be eligible to vest in the award if and when the performance target is achieved. ASU 2014-12 is intended to resolve the diverse accounting treatment of these types of awards in practice. Many reporting entities were accounting for these types of performance targets as non-vesting conditions that affect the grant-date fair value of the award while other entities treated these performance targets as performance conditions that do not affect the grant-date fair value of the award. ASU 2014-12 clarifies that these types of performance targets should be treated as performance conditions that do not impact the grant-date fair value of the award.
	This guidance is effective for annual periods and interim periods within those annual periods, beginning after December 15, 2015. The implementation of ASU 2014-12 will not affect us, as we are currently recording expense consistent with the requirements of this accounting update.

Statements_of_Cash_Flow

Statements of Cash Flow	9 Months Ended
	Sep. 30, 2014
Supplemental Cash Flow Information [Abstract]	'
Statements of Cash Flow	'
	Statements of Cash Flow
	Supplemental cash flow information for Nine Months 2014 and 2013 is as follows:
		Nine Months ended September 30,
	($ in thousands)	2014		2013
	Cash paid during the period for:
	Interest	$	14,089	13,325
	Federal income tax	4,699		17,000
	Non-cash items:
	Tax-free exchange of fixed income securities, available-for-sale ("AFS")	14,954		23,733
	Tax-free exchange of fixed income securities, held-to-maturity ("HTM")	4,288		15,820
	Stock split related to equity securities, AFS	334		—
	Assets acquired under capital lease arrangements	4,853		2,290
	At September 30, 2014, included in "Other assets" on the Consolidated Balance Sheets was $8.1 million of cash received from the NFIP, which is restricted to pay flood claims under the WYO program.

Investments

Investments	9 Months Ended
	Sep. 30, 2014
Investments [Abstract]	'
Investments	'
	Investments
	(a) The amortized cost, net unrealized gains and losses, carrying value, unrecognized holding gains and losses, and fair value of HTM fixed income securities as of September 30, 2014 and December 31, 2013 were as follows:
	September 30, 2014
	($ in thousands)	Amortized			Net			Carrying			Unrecognized			Unrecognized Holding		Fair
		Cost			Unrealized Gains			Value			Holding			Losses		Value
					(Losses)						Gains
	Foreign government	$	5,292		68			5,360			47			—		5,407
	Obligations of state and political subdivisions	301,216			2,472			303,688			13,921			—		317,609
	Corporate securities	20,303			(325	)		19,978			2,749			(1	)	22,726
	Asset-backed securities (“ABS”)	3,111			(530	)		2,581			543			—		3,124
	Commercial mortgage-backed securities (“CMBS”)	4,953			(478	)		4,475			849			—		5,324
	Total HTM fixed income securities	$	334,875		1,207			336,082			18,109			(1	)	354,190
	December 31, 2013
	($ in thousands)	Amortized			Net			Carrying			Unrecognized			Unrecognized Holding		Fair
		Cost			Unrealized Gains			Value			Holding			Losses		Value
					(Losses)						Gains
	Foreign government	$	5,292		131			5,423			168			—		5,591
	Obligations of state and political subdivisions	348,109			4,013			352,122			17,634			—		369,756
	Corporate securities	28,174			(346	)		27,828			2,446			—		30,274
	ABS	3,413			(655	)		2,758			657			—		3,415
	CMBS	5,634			(886	)		4,748			3,197			—		7,945
	Total HTM fixed income securities	$	390,622		2,257			392,879			24,102			—		416,981
	Unrecognized holding gains and losses of HTM securities are not reflected in the Financial Statements, as they represent fair value fluctuations from the later of: (i) the date a security is designated as HTM; or (ii) the date that an other-than-temporary impairment (“OTTI”) charge is recognized on an HTM security, through the date of the balance sheet. Our HTM securities had an average duration of 2.0 years as of September 30, 2014.
	(b) The cost/amortized cost, unrealized gains and losses, and fair value of AFS securities as of September 30, 2014 and December 31, 2013 were as follows:
	September 30, 2014
	($ in thousands)	Cost/			Unrealized			Unrealized			Fair
		Amortized			Gains			Losses			Value
		Cost
	U.S. government and government agencies	$	143,742		8,210			(263	)		151,689
	Foreign government	27,041			832			(6	)		27,867
	Obligations of states and political subdivisions	1,196,478			34,533			(1,777	)		1,229,234
	Corporate securities	1,725,290			44,571			(6,631	)		1,763,230
	ABS	146,557			791			(382	)		146,966
	CMBS1	164,934			2,077			(1,493	)		165,518
	Residential mortgage-backed	480,210			7,664			(4,740	)		483,134
	securities (“RMBS”)2
	AFS fixed income securities	3,884,252			98,678			(15,292	)		3,967,638
	AFS equity securities	180,419			34,797			(3,950	)		211,266
	Total AFS securities	$	4,064,671		133,475			(19,242	)		4,178,904
	December 31, 2013
	($ in thousands)	Cost/			Unrealized			Unrealized			Fair
		Amortized			Gains			Losses			Value
		Cost
	U.S. government and government agencies	$	163,218		10,661			(504	)		173,375
	Foreign government	29,781			906			(72	)		30,615
	Obligations of states and political subdivisions	946,455			25,194			(20,025	)		951,624
	Corporate securities	1,707,928			44,004			(17,049	)		1,734,883
	ABS	140,430			934			(468	)		140,896
	CMBS1	172,288			2,462			(3,466	)		171,284
	RMBS2	515,877			7,273			(10,291	)		512,859
	AFS fixed income securities	3,675,977			91,434			(51,875	)		3,715,536
	AFS equity securities	155,350			37,517			(96	)		192,771
	Total AFS securities	$	3,831,327		128,951			(51,971	)		3,908,307
	1 CMBS includes government guaranteed agency securities with a fair value of $17.6 million at September 30, 2014 and $30.0 million at December 31, 2013.
	2 RMBS includes government guaranteed agency securities with a fair value of $35.9 million at September 30, 2014 and $55.2 million at December 31, 2013.
	Unrealized gains and losses of AFS securities represent fair value fluctuations from the later of: (i) the date a security is designated as AFS; or (ii) the date that an OTTI charge is recognized on an AFS security, through the date of the balance sheet. These unrealized gains and losses are recorded in Accumulated other comprehensive income ("AOCI") on the Consolidated Balance Sheets.
	(c) The following tables summarize, for all securities in a net unrealized/unrecognized loss position at September 30, 2014 and December 31, 2013, the fair value and gross pre-tax net unrealized/unrecognized loss by asset class and by length of time those securities have been in a net loss position:
	September 30, 2014	Less than 12 months						12 months or longer
	($ in thousands)	Fair Value			Unrealized			Fair Value			Unrealized
					Losses1						Losses1
	AFS securities
	U.S. government and government agencies	$	1,001		—			13,219			(263	)
	Foreign government	4,755			(6	)		—			—
Obligations of states and political subdivisions	121,728			(292	)		98,944			(1,485	)
Corporate securities	274,501			(1,529	)		158,127			(5,102	)
ABS	47,542			(134	)		14,149			(248	)
CMBS	16,969			(89	)		57,634			(1,404	)
RMBS	30,958			(101	)		163,237			(4,639	)
Total fixed income securities	497,454			(2,151	)		505,310			(13,141	)
Equity securities	35,229			(3,950	)		—			—
Subtotal	$	532,683		(6,101	)		505,310			(13,141	)
	Less than 12 months									12 months or longer
($ in thousands)	Fair			Unrealized			Unrecognized			Fair			Unrealized		Unrecognized
	Value			Losses1			Gains2			Value			Losses1		Gains2
HTM securities
Obligations of states and political subdivisions	460			(9	)		8			—			—		—
ABS	—			—			—			2,428			(530	)	516
Subtotal	$	460		(9	)		8			2,428			(530	)	516
Total AFS and HTM	$	533,143		(6,110	)		8			507,738			(13,671	)	516
December 31, 2013	Less than 12 months						12 months or longer
($ in thousands)	Fair			Unrealized			Fair Value			Unrealized
	Value			Losses1						Losses1
AFS securities
U.S. government and government agencies	$	16,955		(500	)		507			(4	)
Foreign government	2,029			(30	)		2,955			(42	)
Obligations of states and political subdivisions	442,531			(19,120	)		13,530			(905	)
Corporate securities	511,100			(15,911	)		14,771			(1,138	)
ABS	68,725			(468	)		—			—
CMBS	100,396			(2,950	)		6,298			(516	)
RMBS	268,943			(10,031	)		2,670			(260	)
Total fixed income securities	1,410,679			(49,010	)		40,731			(2,865	)
Equity securities	1,124			(96	)		—			—
Subtotal	$	1,411,803		(49,106	)		40,731			(2,865	)
	Less than 12 months									12 months or longer
($ in thousands)	Fair			Unrealized			Unrecognized			Fair			Unrealized		Unrecognized
	Value			Losses1			Gains2			Value			Losses1		Gains2
HTM securities
Obligations of states and political subdivisions	$	65		(5	)		5			441			(20	)	14
ABS	—			—			—			2,490			(655	)	621
Subtotal	65			(5	)		5			2,931			(675	)	635
Total AFS and HTM	$	1,411,868		(49,111	)		5			43,662			(3,540	)	635
1 Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI.  In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.
2 Unrecognized gains represent fair value fluctuations from the later of:  (i) the date a security is designated as HTM; or (ii) the date that an OTTI charge is recognized on an HTM security.
The table below provides our net unrealized/unrecognized loss positions by impairment severity as of September 30, 2014 compared to December 31, 2013:
($ in thousands)
September 30, 2014					December 31, 2013
Number of	% of Market/Book	Unrealized/			Number of		% of	Unrealized/
Issues		Unrecognized Loss			Issues		Market/Book	Unrecognized Loss
404	80% - 99%	$	16,417		556		80% - 99%	$	51,835
2	60% - 79%	2,840			1		60% - 79%	176
—	40% - 59%	—			—		40% - 59%	—
—	20% - 39%	—			—		20% - 39%	—
—	0% - 19%	—			—		0% - 19%	—
		$	19,257					$	52,011
At September 30, 2014, we had 406 securities in an aggregate unrealized/unrecognized loss position of $19.3 million, compared to 557 securities in an aggregate unrealized/unrecognized loss position of $52.0 million at December 31, 2013. This improvement was mainly driven by a lower interest rate environment. Fixed income security pricing in the marketplace has improved reflecting the 54 basis point decrease in 10-year U.S. Treasury Note yields during Nine Months 2014.
At September 30, 2014, $13.2 million of the aggregate unrealized/unrecognized losses related to securities that have been in a loss position for more than 12 months, while at December 31, 2013, these losses amounted to $2.9 million. Despite these securities being in a loss position, the nature of the loss is interest-rate related as opposed to credit-related concerns, as was evidenced by the fact that the severity of impairment on these securities improved from an average of 6% of amortized cost at year end to an average of 3% of amortized cost at the end of the third quarter. This movement is reflective of the overall interest rate decline experienced during the year.
For a discussion regarding the impact of interest rate movements on our fixed income securities portfolio, refer to Item 7A. "Quantitative and Qualitative Disclosures About Market Risk." in our 2013 Annual Report.
We have reviewed the securities in the tables above in accordance with our OTTI policy, as described in Note 2. “Summary of Significant Accounting Policies” in Item 8. “Financial Statements and Supplementary Data.” of our 2013 Annual Report.
In addition, we do not intend to sell any securities in an unrealized/unrecognized loss position, nor do we believe we will be required to sell these securities, and therefore we have concluded that they are temporarily impaired as of September 30, 2014. This conclusion reflects our current judgment as to the financial position and future prospects of the entity that issued the investment security and underlying collateral. If our judgment about an individual security changes in the future, we may ultimately record a credit loss after having originally concluded that one did not exist, which could have a material impact on our net income and financial position in future periods.
(d) Fixed income securities at September 30, 2014, by contractual maturity, are shown below. Mortgage-backed securities ("MBS") are included in the maturity tables using the estimated average life of each security. Expected maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations, with or without call or prepayment penalties.
Listed below are HTM fixed income securities at September 30, 2014:
($ in thousands)	Carrying Value			Fair Value
Due in one year or less	$	99,364		100,786
Due after one year through five years	220,937			235,038
Due after five years through 10 years	15,781			18,366
Total HTM fixed income securities	$	336,082		354,190
Listed below are AFS fixed income securities at September 30, 2014:
($ in thousands)	Fair Value
Due in one year or less	$	435,053
Due after one year through five years	1,915,327
Due after five years through 10 years	1,507,315
Due after 10 years	109,943
Total AFS fixed income securities	$	3,967,638
(e) The following table summarizes our other investment portfolio by strategy and the remaining commitment amount associated with each strategy:
Other Investments	Carrying Value						September 30,
							2014
($ in thousands)	September 30,			December 31,			Remaining Commitment
	2014			2013
Alternative Investments
Secondary private equity	$	23,064		25,618			6,978
Private equity	21,569			20,192			9,181
Energy/power generation	16,659			17,361			6,984
Mezzanine financing	11,273			12,738			13,774
Real estate	11,212			11,698			10,061
Distressed debt	9,205			11,579			2,981
Venture capital	7,115			7,025			350
Total alternative investments	100,097			106,211			50,309
Other securities	6,451			1,664			—
Total other investments	$	106,548		107,875			50,309
For a description of our seven alternative investment strategies, as well as information regarding redemption, restrictions, and fund liquidations, refer to Note 5. “Investments” in Item 8. “Financial Statements and Supplementary Data.” of our 2013 Annual Report.
The following table sets forth gross summarized financial information for our other investments portfolio, including the portion not owned by us. The investments are carried under the equity method of accounting. The last line of the table below reflects our share of the aggregate income, which is the portion included in our Financial Statements. As the majority of these investments report results to us on a one quarter lag, the summarized financial statement information for the three and nine-month periods ended September 30 is based on the investments' results through June 30 and is as follows:
Income Statement Information	Quarter ended September 30,1						Nine Months ended September 30,2
($ in millions)	2014			2013			2014				2013
Net investment income	$	81.3		97.8			$	167			352.8
Realized (losses) gains	(26.1		)	162.8			171.5				762.5
Net change in unrealized appreciation	628.6			104.8			1,471.00				85.9
Net income	$	683.8		365.4			$	1,809.50			1,201.20
Selective’s insurance subsidiaries’ other investments income	$	3.9		2.6			$	12.7			10.1
1 The majority of these results are for the second quarter of each respective year.
2 The majority of these results are for the nine months ended June 30 of each respective year.
(f) We have pledged certain AFS fixed income securities as collateral related to: (i) our outstanding borrowing of $58 million with the Federal Home Loan Bank of Indianapolis ("FHLBI"); and (ii) our reinsurance obligations related to our 2011 acquisition of our E&S book of business. In addition, certain securities were on deposit with various state and regulatory agencies to comply with insurance laws. We retain all rights regarding all securities pledged as collateral.
The following table summarizes the market value of these securities at September 30, 2014:
($ in millions)	FHLBI Collateral			Reinsurance Collateral			State and Regulatory Deposits			Total
U.S. government and government agencies	$	22.8		—			25.6			48.4
Obligations of states and political subdivisions	—			5.7			—			5.7
Corporate securities	—			5.3			—			5.3
ABS	—			2			—			2
CMBS	1.2			—			—			1.2
RMBS	37.6			2.3			—			39.9
Total pledged as collateral	$	61.6		15.3			25.6			102.5
(g) The components of pre-tax net investment income earned for the periods indicated were as follows:
	Quarter ended September 30,						Nine Months ended September 30,
($ in thousands)	2014			2013			2014				2013
Fixed income securities	$	30,706		30,569			$	95,515			$	90,956
Equity securities	1,909			1,341			5,094				4,422
Short-term investments	15			21			48				102
Other investments	3,906			2,639			12,677				10,110
Investment expenses	(2,244		)	(2,113	)		(6,734		)		(6,260		)
Net investment income earned	$	34,292		32,457			106,600				99,330
(h) The following tables summarize OTTI by asset type for the periods indicated. We had no OTTI charges in Third Quarter 2014:
Third Quarter 2013	Gross			Included in Other Comprehensive Income ("OCI")			Recognized in Earnings
($ in thousands)
AFS securities
Equity securities	$	680		—			680
OTTI losses	$	680		—			680
Nine Months 2014	Gross			Included in OCI			Recognized in
($ in thousands)							Earnings
AFS securities
Equity securities	$	1,382		—			1,382
OTTI losses	$	1,382		—			1,382
Nine Months 2013	Gross			Included in OCI			Recognized in Earnings
($ in thousands)
HTM fixed income securities
ABS	$	(44	)	(47	)		3
Total HTM fixed income securities	(44		)	(47	)		3
AFS fixed income securities
RMBS	(22		)	(30	)		8
Total AFS fixed income securities	(22		)	(30	)		8
Equity securities	1,326			—			1,326
Total AFS securities	1,304			(30	)		1,334
Other investments	1,847			—			1,847
OTTI losses	$	3,107		(77	)		3,184
For a discussion of our evaluation for OTTI of fixed income securities, short-term investments, equity securities, and other investments, refer to Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2013 Annual Report.
The following tables set forth, for the periods indicated, credit loss impairments on fixed income securities for which a portionof the OTTI charge was recognized in OCI, and the corresponding changes in such amounts:
	Quarter ended September 30,
($ in thousands)	2014			2013
Balance, beginning of period	$	5,534		7,488
Addition for the amount related to credit loss for which an OTTI was not previously recognized	—			—
Reductions for securities sold during the period	(90		)	—
Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost	—			—
Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected	—			—
Additional increases to the amount related to credit loss for which an OTTI was previously recognized	—			—
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected	—			—
Balance, end of period	$	5,444		7,488
	Nine Months ended September 30,
($ in thousands)	2014			2013
Balance, beginning of period	$	7,488		7,477
Addition for the amount related to credit loss for which an OTTI was not previously recognized	—			—
Reductions for securities sold during the period	(2,044		)	—
Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost	—			—
Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected	—			—
Additional increases to the amount related to credit loss for which an OTTI was previously recognized	—			11
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected	—			—
Balance, end of period	$	5,444		7,488
(i) The components of net realized gains, excluding OTTI charges, for the periods indicated were as follows:
	Quarter ended September 30,					Nine Months ended September 30,
($ in thousands)	2014			2013		2014			2013
HTM fixed income securities
Gains	$	—		32		3			35
Losses	(4		)	(37	)	(18	)		(86	)
AFS fixed income securities
Gains	695			662		1,633			2,580
Losses	(29		)	(31	)	(172	)		(330	)
AFS equity securities
Gains	14,576			13,801		27,255			24,272
Losses	(8		)	(236	)	(332	)		(407	)
Other investments
Gains	1			—		1			—
Losses	—			(80	)	—			(940	)
Total other net realized investment gains	15,231			14,111		28,370			25,124
Total OTTI charges recognized in earnings	—			(680	)	(1,382	)		(3,184	)
Total net realized gains	$	15,231		13,431		26,988			21,940
Realized gains and losses on the sale of investments are determined on the basis of the cost of the specific investments sold. The $15.2 million and $28.4 million in net realized gains in Third Quarter and Nine Months 2014, respectively, were primarily related to the sale of AFS equity securities due to the rebalancing of our high dividend yield strategy holdings within our equity portfolio.
Of the $14.1 million and $25.1 million in net realized gains in Third Quarter and Nine Months 2013, $13.5 million and $19.1 million, respectively, were related to the sale of AFS equity securities due to the rebalancing of our high dividend yield strategy holdings within our equity portfolio. In addition, $4.7 million in net realized gains in Nine Months 2013, was related to the sale of a private equity security due to the acquisition of this investment by a third party.
Proceeds from the sale of AFS securities were $89.9 million in Third Quarter 2014 and $221.5 million in Nine Months 2014, and $67.2 million and $116.3 million in the same periods a year ago.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	Fair Value Measurements
	The following table presents the carrying amounts and estimated fair values of our financial instruments as of September 30, 2014 and December 31, 2013:
			September 30, 2014						December 31, 2013
	($ in thousands)		Carrying Amount			Fair			Carrying Amount			Fair
						Value						Value
	Financial Assets
	Fixed income securities:
	HTM		$	336,082		354,190			392,879			416,981
	AFS		3,967,638			3,967,638			3,715,536			3,715,536
	Equity securities, AFS		211,266			211,266			192,771			192,771
	Short-term investments		181,593			181,593			174,251			174,251
	Financial Liabilities
	Notes payable:
	2.90% borrowings from FHLBI		13,000			13,085			13,000			13,319
	1.25% borrowings from FHLBI		45,000			45,220			45,000			45,259
	7.25% Senior Notes		49,896			56,970			49,916			50,887
	6.70% Senior Notes		99,398			110,310			99,498			98,247
	5.875% Senior Notes		185,000			179,598			185,000			146,298
	Total notes payable		$	392,294		405,183			392,414			354,010
	The fair values of our financial assets and liabilities are generated using various valuation techniques and are placed into the fair value hierarchy considering the following: (i) the highest priority is given to quoted prices in active markets for identical assets (Level 1); (ii) the next highest priority is given to quoted prices in markets that are not active or inputs that are observable either directly or indirectly, including quoted prices for similar assets in markets that are not active and other inputs that can be derived principally from, or corroborated by, observable market data for substantially the full term of the assets (Level 2); and (iii) the lowest priority is given to unobservable inputs supported by little or no market activity and that reflect our assumptions about the exit price, including assumptions that market participants would use in pricing the asset (Level 3). An asset or liability's classification within the fair value hierarchy is based on the lowest level of significant input to its valuation. Transfers between levels in the fair value hierarchy are recognized at the end of the reporting period.
	For a discussion of the techniques used to value our financial assets and liabilities, refer to Note 2. "Summary of Significant Accounting Policies" in Item 8. "Financial Statements and Supplementary Data." of our 2013 Annual Report.
	The following tables provide quantitative disclosures of our financial assets that were measured at fair value at September 30, 2014 and December 31, 2013:
	September 30, 2014					Fair Value Measurements Using
	($ in thousands)		Assets			Quoted Prices in			Significant Other			Significant Unobservable
			Measured at			Active Markets for			Observable			Inputs
			Fair Value			Identical Assets/			Inputs			(Level 3)
			at 9/30/2014			Liabilities (Level 1)1			(Level 2)1
	Description
	Measured on a recurring basis:
	AFS:
	U.S. government and government agencies		$	151,689		51,467			100,222			—
	Foreign government		27,867			—			27,867			—
	Obligations of states and political subdivisions		1,229,234			—			1,229,234			—
	Corporate securities		1,763,230			—			1,763,230			—
	ABS		146,966			—			146,966			—
	CMBS		165,518			—			165,518			—
	RMBS		483,134			—			483,134			—
	Total AFS fixed income securities		3,967,638			51,467			3,916,171			—
	Equity securities		211,266			208,366			—			2,900
	Total AFS Securities		4,178,904			259,833			3,916,171			2,900
	Short-term investments		181,593			181,593			—			—
	Total assets measured at fair value		$	4,360,497		441,426			3,916,171			2,900
	1	There were no transfers of securities between Level 1 and Level 2.
	December 31, 2013					Fair Value Measurements Using
	($ in thousands)		Assets			Quoted Prices in			Significant			Significant Unobservable
			Measured at			Active Markets for			Other Observable			Inputs
			Fair Value			Identical Assets/Liabilities			Inputs			(Level 3)
			at 12/31/13			(Level 1)1			(Level 2)1
	Description
	Measured on a recurring basis:
	AFS:
	U.S. government and government agencies		$	173,375		52,153			121,222			—
	Foreign government		30,615			—			30,615			—
	Obligations of states and political subdivisions		951,624			—			951,624			—
	Corporate securities		1,734,883			—			1,734,883			—
	ABS		140,896			—			140,896			—
	CMBS		171,284			—			171,284			—
	RMBS		512,859			—			512,859			—
	Total AFS fixed income securities		3,715,536			52,153			3,663,383			—
	Equity securities		192,771			189,871			—			2,900
	Total AFS Securities		3,908,307			242,024			3,663,383			2,900
	Short-term investments		174,251			174,251			—			—
	Total assets measured at fair value		$	4,082,558		416,275			3,663,383			2,900
1	There were no transfers of securities between Level 1 and Level 2.
There were no changes in the fair value of securities measured using Level 3 prices during Nine Months 2014. The following table provides a summary of these changes during full year 2013:
31-Dec-13
($ in thousands)		Government			Corporate				ABS			CMBS			Equity			Receivable for			Total
																		Proceeds
																		Related to Sale
																		of Selective HR Solutions ("Selective HR")
Fair value, December 31, 2012		$	19,789		2,946				6,068			7,162			3,607			2,705			42,277
Total net (losses) gains for the period included in:
OCI1		(537		)	(7		)		(74		)	772			3,935			—			4,089
Net income2,3		(76		)	—				—			361			—			(1,480		)	(1,195		)
Purchases		—			—				—			—			—			—			—
Sales		—			—				—			—			—			—			—
Issuances		—			—				—			—			—			—			—
Settlements		(1,847		)	(168		)		—			(2,420		)	—			(225		)	(4,660		)
Transfers into Level 3		—			—				—			—			—			—			—
Transfers out of Level 3		(17,329		)	(2,771		)		(5,994		)	(5,875		)	(4,642		)	(1,000		)	(37,611		)
Fair value, December 31, 2013		$	—		$	—			$	—		$	—		$	2,900		$	—		$	2,900
1 Amounts are reported in “Unrealized holding (losses) gains arising during period” on the Consolidated Statements of Comprehensive Income in our 2013 Annual Report.
2 Amounts are reported in “Net realized gains” for realized gains and losses and “Net investment income earned” for amortization of securities on the Consolidated Statements of Income in our 2013 Annual Report.
3 For the receivable related to the sale of Selective HR, amounts in "Loss on disposal of discontinued operations, net of tax" relate to an impairment charge and amounts in "Other income" relate to interest accretion on the Consolidated Statements of Income in our 2013 Annual Report.
As discussed in Note 2. "Summary of Significant Accounting Policies," in Item 8. "Financial Statements and Supplementary Data." in our 2013 Annual Report, the fair value of our Level 3 fixed income securities is typically obtained through non-binding broker quotes based on unobservable inputs, which we review for reasonableness. There were no fixed income securities measured using Level 3 inputs at September 30, 2014 and December 31, 2013. However, in 2013, fixed income securities with a fair value of $32.0 million were transferred out of Level 3 during the year due to the availability of Level 2 pricing at December 31, 2013 that was not available previously.
Equity securities with a fair value of $2.9 million were measured using Level 3 inputs at September 30, 2014 and at December 31, 2013. An equity security with a fair value of $4.6 million was transferred out of Level 3 during 2013 due to the availability of Level 2 pricing at the date of transfer. In addition, the receivable related to the sale of Selective HR was settled during 2013 and as a result was also transferred out of Level 3.
The following tables provide quantitative information regarding our financial assets and liabilities that were disclosed at fair value at September 30, 2014 and December 31, 2013:
September 30, 2014					Fair Value Measurements Using
($ in thousands)		Assets/			Quoted Prices in			Significant Other			Significant
		Liabilities			Active Markets for			Observable			Unobservable
		Disclosed at			Identical Assets/			Inputs			Inputs
		Fair Value at 9/30/2014			Liabilities			(Level 2)			(Level 3)
					(Level 1)
Financial Assets
HTM:
Foreign government		$	5,407		—			5,407			—
Obligations of states and political subdivisions		317,609			—			317,609			—
Corporate securities		22,726			—			22,726			—
ABS		3,124			—			3,124			—
CMBS		5,324			—			5,324			—
Total HTM fixed income securities		$	354,190		—			354,190			—
Financial Liabilities
Notes payable:
2.90% borrowings from FHLBI		$	13,085		—			13,085			—
1.25% borrowings from FHLBI		45,220			—			45,220			—
7.25% Senior Notes		56,970			—			56,970			—
6.70% Senior Notes		110,310			—			110,310			—
5.875% Senior Notes		179,598			179,598			—			—
Total notes payable		$	405,183		179,598			225,585			—
December 31, 2013					Fair Value Measurements Using
($ in thousands)		Assets/			Quoted Prices in			Significant Other			Significant
		Liabilities			Active Markets for			Observable			Unobservable
		Disclosed at			Identical Assets/			Inputs			Inputs
		Fair Value at 12/31/2013			Liabilities			(Level 2)			(Level 3)
					(Level 1)
Financial Assets
HTM:
Foreign government		$	5,591		—			5,591			—
Obligations of states and political subdivisions		369,756			—			369,756			—
Corporate securities		30,274			—			30,274			—
ABS		3,415			—			3,415			—
CMBS		7,945			—			7,945			—
Total HTM fixed income securities		$	416,981		—			416,981			—
Financial Liabilities
Notes payable:
2.90% borrowings from FHLBI		$	13,319		—			13,319			—
1.25% borrowings from FHLBI		45,259			—			45,259			—
7.25% Senior Notes		50,887			—			50,887			—
6.70% Senior Notes		98,247			—			98,247			—
5.875% Senior Notes		146,298			146,298			—			—
Total notes payable		$	354,010		146,298			207,712			—

Reinsurance

Reinsurance	9 Months Ended
	Sep. 30, 2014
Reinsurance Disclosures [Abstract]	'
Reinsurance	'
	Reinsurance
	The following table contains a listing of direct, assumed, and ceded reinsurance amounts for premiums written, premiums earned, and loss and loss expenses incurred for the periods indicated. For more information concerning reinsurance, refer to Note 8. “Reinsurance” in Item 8. “Financial Statements and Supplementary Data.” of our 2013 Annual Report.
		Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)	2014			2013		2014		2013
	Premiums written:
	Direct	$	592,858		570,849		1,723,063		1,650,855
	Assumed	5,780			22,053		19,467		34,913
	Ceded	(103,517		)	(100,154	)	(290,836	)	(280,719	)
	Net	$	495,121		492,748		1,451,694		1,405,049
	Premiums earned:
	Direct	$	548,734		518,307		1,630,347		1,516,454
	Assumed	6,789			11,066		27,359		32,480
	Ceded	(92,884		)	(91,805	)	(274,947	)	(264,174	)
	Net	$	462,639		437,568		1,382,759		1,284,760
	Loss and loss expense incurred:
	Direct	$	304,525		350,648		995,581		1,055,248
	Assumed	5,362			7,264		20,218		22,758
	Ceded	(38,955		)	(74,595	)	(126,526	)	(245,246	)
	Net	$	270,932		283,317		889,273		832,760
	Direct premiums earned increases in Third Quarter 2014 and Nine Months 2014 compared to Third Quarter 2013 and Nine Months 2013 reflect pure price increases coupled with stable retention that we have achieved in our Standard Insurance Operations. These increases were consistent with the fluctuation in DPW for the twelve-month period ended September 30, 2014 compared to the twelve-month period ended September 30, 2013.
	Assumed premiums written and earned decreased in Third Quarter 2014 and Nine Months 2014 compared to the same periods last year as a result of the March 2014 sale of the renewal rights to our self-insured group, or "SIG," book of pooled public entity business.
	Direct loss and loss expense incurred decreased by $46.1 million in Third Quarter 2014 compared to Third Quarter 2013 driven by: (i) lower catastrophe losses; (ii) favorable prior year casualty reserve development; and (iii) a $4.0 million reduction in our estimated ultimate exposure related to Hurricane Sandy, $3.6 million of which is ceded under our catastrophe excess of loss treaty.
	In addition, the ceded premiums and losses related to our participation in the NFIP, under which 100% of our flood premiums, losses, and loss expenses are ceded to the NFIP, are as follows:
	Ceded to NFIP	Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)	2014			2013		2014		2013
	Ceded premiums written	$	(69,922	)	(64,196	)	(193,000	)	(183,364	)
	Ceded premiums earned	(60,761		)	(57,920	)	(178,260	)	(169,697	)
	Ceded loss and loss expense incurred	(14,008		)	(34,879	)	(48,099	)	(162,780	)

Segment_Information

Segment Information	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Segment Information	'
	Segment Information
	The disaggregated results of our three operating segments are used by senior management to manage our operations. These segments are evaluated based on the following:
	•	Our Standard Insurance Operations segment and our E&S Insurance Operations segment are evaluated based on statutory underwriting results (net premiums earned, incurred loss and loss expenses, policyholders dividends, policy acquisition costs, and other underwriting expenses), and statutory combined ratios; and
	•	Our Investments segment is evaluated based on after-tax net investment income and net realized gains and losses.
	In computing the results of each segment, we do not make adjustments for interest expense or net general corporate expenses. While we do not fully allocate taxes to all segments, we do allocate taxes to our Investments segment as we manage that segment on after-tax results. We do not maintain separate investment portfolios for the segments and therefore, do not allocate assets to the segments.
	In the first quarter of 2014, we sold the renewal rights to our $38 million self-insured group, or "SIG," book of business within the Standard Insurance Operations segment. We decided to opportunistically sell this small and specialized book of pooled business as a significant portion of the business was produced outside of our standard lines footprint, and proved difficult to grow. As this was a renewal rights sale, we will continue to service policies that were in force at the date of the sale. We continue to remain active in the municipal and public school marketplace for individual risks that procure traditional insurance programs rather than pooling arrangements. The proceeds from this sale, which amounted to $8 million, are included in "Miscellaneous income" within the table below as a component of the Standard Insurance Operations revenue.
	The following summaries present revenues from continuing operations (net investment income and net realized gains on investments in the case of the Investments segment) and pre-tax income from continuing operations for the individual segments:
	Revenue by Segment		Quarter ended					Nine Months ended
			September 30,					September 30,
	($ in thousands)		2014			2013		2014			2013
	Standard Insurance Operations:
	Net premiums earned:
	Commercial automobile		$	83,536		79,138		249,224			230,191
	Workers compensation		66,732			66,510		205,137			197,449
	General liability		110,894			100,925		331,303			298,394
	Commercial property		61,304			57,004		182,716			165,356
	Businessowners’ policies		21,649			19,629		63,797			56,794
	Bonds		4,791			4,705		14,281			14,244
	Other		3,237			3,051		9,633			9,036
	Total Standard Commercial Lines		352,143			330,962		1,056,091			971,464
	Personal automobile		37,695			38,513		113,943			115,432
	Homeowners		33,957			32,374		100,831			95,211
	Other		2,725			3,827		8,965			10,655
	Total Standard Personal Lines		74,377			74,714		223,739			221,298
	Total Standard Insurance Operations net premiums earned		426,520			405,676		1,279,830			1,192,762
	Miscellaneous income		3,196			3,342		14,923			9,590
	Total Standard Insurance Operations revenue		429,716			409,018		1,294,753			1,202,352
	E&S Insurance Operations:
	Net premiums earned		36,119			31,892		102,929			91,998
	Investments:
	Net investment income		34,292			32,457		106,600			99,330
	Net realized investment gains		15,231			13,431		26,988			21,940
	Total investment revenues		49,523			45,888		133,588			121,270
	Total all segments		515,358			486,798		1,531,270			1,415,620
	Other income		—			15		8			87
	Total revenues from continuing operations		$	515,358		486,813		1,531,278			1,415,707
	Income from Continuing Operations before Federal Income Tax		Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)		2014			2013		2014				2013
	Standard Insurance Operations:
	Commercial Lines underwriting gain		$	27,771		8,776		$	39,844			24,621
	Personal Lines underwriting gain		8,037			1,362		95				4,360
	Total Standard Insurance Operations underwriting gain, before federal income tax		35,808			10,138		39,939				28,981
	GAAP combined ratio		91.6		%	97.5		96.9		%		97.6
	Statutory combined ratio		90.5		%	96		96.3		%		96.6
	E&S Insurance Operations:
	Underwriting (loss) gain		(1,371		)	13		(433		)		(2,186	)
	GAAP combined ratio		103.8		%	100		100.4		%		102.4
	Statutory combined ratio		102.9		%	100.5		100.3		%		101.9
	Investments:
	Net investment income		34,292			32,457		106,600				99,330
	Net realized investment gains		15,231			13,431		26,988				21,940
	Total investment income, before federal income tax		49,523			45,888		133,588				121,270
	Tax on investment income		13,858			12,648		36,374				31,960
	Total investment income, after federal income tax		35,665			33,240		97,214				89,310
	Reconciliation of Segment Results to Income from Continuing Operations,		Quarter ended					Nine Months ended
	before Federal Income Tax		September 30,					September 30,
	($ in thousands)		2014			2013		2014				2013
	Standard Insurance Operations underwriting gain, before federal income tax		$	35,808		10,138		$	39,939			28,981
	E&S Insurance Operations underwriting (loss) gain, before federal income tax		(1,371		)	13		(433		)		(2,186	)
	Investment income, before federal income tax		49,523			45,888		133,588				121,270
	Total all segments		83,960			56,039		173,094				148,065
	Interest expense		(5,558		)	(5,570	)	(16,544		)		(16,971	)
	General corporate and other expenses		(3,076		)	(5,984	)	(16,619		)		(21,540	)
Income from continuing operations, before federal income tax		$	75,326		44,485		$	139,931			109,554

Retirement_Plans

Retirement Plans	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Retirement Plans	'
	Retirement Plans
	The following table shows the net periodic benefit cost related to the Retirement Income Plan for Selective Insurance Company of America (“Retirement Income Plan”) and the life insurance benefits provided to eligible Selective Insurance Company of America retirees (referred to as the "Retirement Life Plan"). For more information concerning these plans, refer to Note 15. “Retirement Plans” in Item 8. “Financial Statements and Supplementary Data.” of our 2013 Annual Report.
		Retirement Income Plan							Retirement Life Plan
		Quarter ended September 30,							Quarter ended September 30,
	($ in thousands)	2014				2013			2014		2013
	Components of Net Periodic Benefit Cost:
	Net Periodic Benefit Cost:
	Service cost	$	1,627			1,857			—		—
	Interest cost	3,253				3,053			73		69
	Expected return on plan assets	(3,919		)		(3,986	)		—		—
	Amortization of unrecognized net actuarial loss	367				772			14		18
	Total net periodic cost	$	1,328			1,696			87		87
		Retirement Income Plan							Retirement Life Plan
		Nine Months ended September 30,							Nine Months ended September 30,
	($ in thousands)	2014				2013			2014		2013
	Components of Net Periodic Benefit Cost:
	Net Periodic Benefit Cost:
	Service cost	$	4,880			6,163			—		—
	Interest cost	9,760				9,407			219		208
	Expected return on plan assets	(11,756		)		(11,819	)		—		—
	Amortization of unrecognized prior service	—				10			—		—
	Amortization of unrecognized net actuarial loss	1,102				3,366			40		53
	Curtailment expense	—				16			—		—
	Total net periodic cost	$	3,986			7,143			259		261
		Retirement Income Plan					Retirement Life Plan
		Nine Months ended September 30,					Nine Months ended September 30,
		2014			2013		2014			2013
	Weighted-Average Expense Assumptions:
	Discount rate	5.16	%		4.66		4.85	%		4.42
	Expected return on plan assets	6.92			7.4		—			—
	Rate of compensation increase	4			4		—			—
	We presently anticipate contributing $10.4 million to the Retirement Income Plan in 2014, $8.0 million of which has been funded as of September 30, 2014.

Comprehensive_Income

Comprehensive Income	9 Months Ended
	Sep. 30, 2014
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]	'
Comprehensive Income	'
	Comprehensive Income
	The components of comprehensive income, both gross and net of tax, for Third Quarter and Nine Months 2014 and 2013 are as follows:
	Third Quarter 2014
	($ in thousands)		Gross				Tax			Net
	Net income		$	75,326			22,164			53,162
	Components of OCI:
	Unrealized losses on investment securities:
	Unrealized holding losses during the period		(13,831		)		(4,843	)		(8,988	)
	Amounts reclassified into net income:
	HTM securities		(373		)		(130	)		(243	)
	Non-credit OTTI		1,200				420			780
	Realized gains on AFS securities		(16,435		)		(5,752	)		(10,683	)
	Net unrealized losses		(29,439		)		(10,305	)		(19,134	)
	Defined benefit pension and post-retirement plans:
	Amounts reclassified into net income:
	Net actuarial loss		381				134			247
	Defined benefit pension and post-retirement plans		381				134			247
	Other comprehensive loss		(29,058		)		(10,171	)		(18,887	)
	Comprehensive income		$	46,268			11,993			34,275
	Third Quarter 2013
	($ in thousands)		Gross				Tax			Net
	Net income		$	44,485			11,832			32,653
	Components of OCI:
	Unrealized losses on investment securities:
	Unrealized holding gains during the period		9,820				3,437			6,383
	Amounts reclassified into net income:
	HTM securities		(472		)		(165	)		(307	)
	Non-credit OTTI		1				—			1
	Realized gains on AFS securities		(13,516		)		(4,731	)		(8,785	)
	Net unrealized losses		(4,167		)		(1,459	)		(2,708	)
	Defined benefit pension and post-retirement plans:
	Amounts reclassified into net income:
	Net actuarial loss		790				277			513
	Defined benefit pension and post-retirement plans		790				277			513
	Other comprehensive loss		(3,377		)		(1,182	)		(2,195	)
	Comprehensive loss		$	41,108			10,650			30,458
	Nine Months 2014
	($ in thousands)		Gross				Tax			Net
	Net income		$	139,931			39,454			100,477
	Components of OCI:
	Unrealized gains on investment securities:
	Unrealized holding gains during the period		64,255				22,488			41,767
	Amounts reclassified into net income:
	HTM securities		(1,050		)		(367	)		(683	)
	Non-credit OTTI		1,669				584			1,085
	Realized gains on AFS securities		(28,672		)		(10,035	)		(18,637	)
	Net unrealized gains		36,202				12,670			23,532
	Defined benefit pension and post-retirement plans:
	Amounts reclassified into net income:
	Net actuarial loss		1,142				400			742
	Defined benefit pension and post-retirement plans		1,142				400			742
	Other comprehensive income		37,344				13,070			24,274
	Comprehensive income		$	177,275			52,524			124,751
	Nine Months 2013
	($ in thousands)		Gross				Tax			Net
	Net income		$	108,019			26,936			81,083
	Components of OCI:
	Unrealized losses on investment securities:
	Unrealized holding losses during the period		(77,810		)		(27,234	)		(50,576	)
	Non-credit OTTI recognized in OCI		77				27			50
	Amounts reclassified into net income:
	HTM securities		(1,803		)		(631	)		(1,172	)
	Non-credit OTTI		14				5			9
Realized gains on AFS securities		(24,780		)		(8,673	)		(16,107	)
Net unrealized losses		(104,302		)		(36,506	)		(67,796	)
Defined benefit pension and post-retirement plans:
Net actuarial gains		44,000				15,400			28,600
Amounts reclassified into net income:
Net actuarial loss		3,419				1,197			2,222
Prior service cost		10				4			6
Curtailment expense		16				5			11
Defined benefit pension and post-retirement plans		47,445				16,606			30,839
Other comprehensive loss		(56,857		)		(19,900	)		(36,957	)
Comprehensive income		$	51,162			7,036			44,126
The balances of, and changes in, each component of AOCI (net of taxes) as of September 30, 2014 are as follows:
September 30, 2014		Net Unrealized (Loss) Gain on Investment Securities
($ in thousands)		OTTI				HTM			All			Investments		Defined Benefit		Total AOCI
		Related				Related			Other			Subtotal		Pension and Post-Retirement Plans
Balance, December 31, 2013		$	(1,599	)		1,467			51,635			51,503		(26,652	)	24,851
OCI before reclassifications		—				—			41,767			41,767		—		41,767
Amounts reclassified from AOCI		1,085				(683	)		(18,637	)		(18,235	)	742		(17,493	)
Net current period OCI		1,085				(683	)		23,130			23,532		742		24,274
Balance, September 30, 2014		$	(514	)		784			74,765			75,035		(25,910	)	49,125
The reclassifications out of AOCI are as follows:
	Quarter ended						Nine Months ended
	September 30,						September 30,
($ in thousands)	2014			2013			2014			2013		Affected Line Item in the Unaudited Consolidated Statement of Income
OTTI related
Amortization of non-credit OTTI losses on HTM securities	—			1			—			14		Net investment income earned
Non-credit OTTI on disposed securities	1,200			—			1,669			—		Net realized gains
	1,200			1			1,669			14		Income from continuing operations, before federal income tax
	(420	)		—			(584	)		(5	)	Total federal income tax expense
	780			1			1,085			9		Net income
HTM related
Unrealized losses (gains) on HTM disposals	12			(19	)		87			(170	)	Net realized gains
Amortization of net unrealized gains on HTM securities	(385	)		(453	)		(1,137	)		(1,633	)	Net investment income earned
	(373	)		(472	)		(1,050	)		(1,803	)	Income from continuing operations, before federal income tax
	130			165			367			631		Total federal income tax expense
	(243	)		(307	)		(683	)		(1,172	)	Net income
Realized gains and losses on AFS and OTTI
Realized gains on AFS disposals and OTTI	(16,435	)		(13,516	)		(28,672	)		(24,780	)	Net realized gains
	(16,435	)		(13,516	)		(28,672	)		(24,780	)	Income from continuing operations, before federal income tax
	5,752			4,731			10,035			8,673		Total federal income tax expense
	(10,683	)		(8,785	)		(18,637	)		(16,107	)	Net income
Defined benefit pension and post-retirement life plans
Net actuarial loss	88			159			263			717		Loss and loss expense incurred
	293			631			879			2,702		Policy acquisition costs
	381			790			1,142			3,419		Income from continuing operations, before federal income tax
Prior service cost	—			—			—			7		Loss and loss adjustment expenses
	—			—			—			3		Policy acquisition costs
	—			—			—			10		Income from continuing operations, before federal income tax
Curtailment expense	—			—			—			16		Policy acquisition costs
	—			—			—			16		Income from continuing operations, before federal income tax
Total defined benefit pension and post-retirement life	381			790			1,142			3,445		Income from continuing operations, before federal income tax
	(134	)		(277	)		(400	)		(1,206	)	Total federal income tax expense
	247			513			742			2,239		Net income
Total reclassifications for the period	(9,899	)		(8,578	)		(17,493	)		(15,031	)	Net income

Litigation

Litigation	9 Months Ended
	Sep. 30, 2014
Loss Contingency, Information about Litigation Matters [Abstract]	'
Litigation	'
	Litigation
	In the ordinary course of conducting business, we are named as defendants in various legal proceedings. Most of these proceedings are claims litigation involving our Insurance Subsidiaries as either: (i) liability insurers defending or providing indemnity for third-party claims brought against insureds; or (ii) insurers defending first-party coverage claims brought against them. We account for such activity through the establishment of unpaid loss and loss expense reserves. We expect that the ultimate liability, if any, with respect to such ordinary course claims litigation, after consideration of provisions made for potential losses and costs of defense, will not be material to our consolidated financial condition, results of operations, or cash flows.
	Our Insurance Subsidiaries are also from time to time involved in other legal actions, some of which assert claims for substantial amounts. These actions include, among others, putative class actions seeking certification of a state or national class. Such putative class actions have alleged, for example, improper reimbursement of medical providers paid under workers compensation and personal and commercial automobile insurance policies. Our Insurance Subsidiaries also are involved from time to time in individual actions in which extra-contractual damages, punitive damages, or penalties are sought, such as claims alleging bad faith in the handling of insurance claims. We believe that we have valid defenses to these cases. We expect that the ultimate liability, if any, with respect to such lawsuits, after consideration of provisions made for estimated losses, will not be material to our consolidated financial condition. Nonetheless, given the large or indeterminate amounts sought in certain of these actions, and the inherent unpredictability of litigation, an adverse outcome in certain matters could, from time to time, have a material adverse effect on our consolidated results of operations or cash flows in particular quarterly or annual periods.

Statements_of_Cash_Flow_Tables

Statements of Cash Flow (Tables)	9 Months Ended
	Sep. 30, 2014
Supplemental Cash Flow Information [Abstract]	'
Schedule of Cash Flow, Supplemental Disclosures	'
		Nine Months ended September 30,
	($ in thousands)	2014		2013
	Cash paid during the period for:
	Interest	$	14,089	13,325
	Federal income tax	4,699		17,000
	Non-cash items:
	Tax-free exchange of fixed income securities, available-for-sale ("AFS")	14,954		23,733
	Tax-free exchange of fixed income securities, held-to-maturity ("HTM")	4,288		15,820
	Stock split related to equity securities, AFS	334		—
	Assets acquired under capital lease arrangements	4,853		2,290

Investments_Tables

Investments (Tables)	9 Months Ended
	Sep. 30, 2014
Investments [Line Items]	'
Schedule of Held-to-maturity Securities	'
	September 30, 2014
	($ in thousands)	Amortized			Net			Carrying			Unrecognized			Unrecognized Holding		Fair
		Cost			Unrealized Gains			Value			Holding			Losses		Value
					(Losses)						Gains
	Foreign government	$	5,292		68			5,360			47			—		5,407
	Obligations of state and political subdivisions	301,216			2,472			303,688			13,921			—		317,609
	Corporate securities	20,303			(325	)		19,978			2,749			(1	)	22,726
	Asset-backed securities (“ABS”)	3,111			(530	)		2,581			543			—		3,124
	Commercial mortgage-backed securities (“CMBS”)	4,953			(478	)		4,475			849			—		5,324
	Total HTM fixed income securities	$	334,875		1,207			336,082			18,109			(1	)	354,190
	December 31, 2013
	($ in thousands)	Amortized			Net			Carrying			Unrecognized			Unrecognized Holding		Fair
		Cost			Unrealized Gains			Value			Holding			Losses		Value
					(Losses)						Gains
	Foreign government	$	5,292		131			5,423			168			—		5,591
	Obligations of state and political subdivisions	348,109			4,013			352,122			17,634			—		369,756
	Corporate securities	28,174			(346	)		27,828			2,446			—		30,274
	ABS	3,413			(655	)		2,758			657			—		3,415
	CMBS	5,634			(886	)		4,748			3,197			—		7,945
	Total HTM fixed income securities	$	390,622		2,257			392,879			24,102			—		416,981
Schedule Of Available For Sale Securities	'
	September 30, 2014
	($ in thousands)	Cost/			Unrealized			Unrealized			Fair
		Amortized			Gains			Losses			Value
		Cost
	U.S. government and government agencies	$	143,742		8,210			(263	)		151,689
	Foreign government	27,041			832			(6	)		27,867
	Obligations of states and political subdivisions	1,196,478			34,533			(1,777	)		1,229,234
	Corporate securities	1,725,290			44,571			(6,631	)		1,763,230
	ABS	146,557			791			(382	)		146,966
	CMBS1	164,934			2,077			(1,493	)		165,518
	Residential mortgage-backed	480,210			7,664			(4,740	)		483,134
	securities (“RMBS”)2
	AFS fixed income securities	3,884,252			98,678			(15,292	)		3,967,638
	AFS equity securities	180,419			34,797			(3,950	)		211,266
	Total AFS securities	$	4,064,671		133,475			(19,242	)		4,178,904
	December 31, 2013
	($ in thousands)	Cost/			Unrealized			Unrealized			Fair
		Amortized			Gains			Losses			Value
		Cost
	U.S. government and government agencies	$	163,218		10,661			(504	)		173,375
	Foreign government	29,781			906			(72	)		30,615
	Obligations of states and political subdivisions	946,455			25,194			(20,025	)		951,624
	Corporate securities	1,707,928			44,004			(17,049	)		1,734,883
	ABS	140,430			934			(468	)		140,896
	CMBS1	172,288			2,462			(3,466	)		171,284
	RMBS2	515,877			7,273			(10,291	)		512,859
	AFS fixed income securities	3,675,977			91,434			(51,875	)		3,715,536
	AFS equity securities	155,350			37,517			(96	)		192,771
	Total AFS securities	$	3,831,327		128,951			(51,971	)		3,908,307
	1 CMBS includes government guaranteed agency securities with a fair value of $17.6 million at September 30, 2014 and $30.0 million at December 31, 2013.
	2 RMBS includes government guaranteed agency securities with a fair value of $35.9 million at September 30, 2014 and $55.2 million at December 31, 2013.
Schedule of Fair Value and Gross Pre-Tax Net Unrealized/Unrecognized Loss of Securities by Length of Time	'
	September 30, 2014	Less than 12 months						12 months or longer
	($ in thousands)	Fair Value			Unrealized			Fair Value			Unrealized
					Losses1						Losses1
	AFS securities
	U.S. government and government agencies	$	1,001		—			13,219			(263	)
	Foreign government	4,755			(6	)		—			—
	Obligations of states and political subdivisions	121,728			(292	)		98,944			(1,485	)
	Corporate securities	274,501			(1,529	)		158,127			(5,102	)
	ABS	47,542			(134	)		14,149			(248	)
	CMBS	16,969			(89	)		57,634			(1,404	)
	RMBS	30,958			(101	)		163,237			(4,639	)
	Total fixed income securities	497,454			(2,151	)		505,310			(13,141	)
	Equity securities	35,229			(3,950	)		—			—
	Subtotal	$	532,683		(6,101	)		505,310			(13,141	)
		Less than 12 months									12 months or longer
	($ in thousands)	Fair			Unrealized			Unrecognized			Fair			Unrealized		Unrecognized
		Value			Losses1			Gains2			Value			Losses1		Gains2
	HTM securities
	Obligations of states and political subdivisions	460			(9	)		8			—			—		—
	ABS	—			—			—			2,428			(530	)	516
	Subtotal	$	460		(9	)		8			2,428			(530	)	516
	Total AFS and HTM	$	533,143		(6,110	)		8			507,738			(13,671	)	516
	December 31, 2013	Less than 12 months						12 months or longer
	($ in thousands)	Fair			Unrealized			Fair Value			Unrealized
		Value			Losses1						Losses1
	AFS securities
	U.S. government and government agencies	$	16,955		(500	)		507			(4	)
	Foreign government	2,029			(30	)		2,955			(42	)
	Obligations of states and political subdivisions	442,531			(19,120	)		13,530			(905	)
	Corporate securities	511,100			(15,911	)		14,771			(1,138	)
	ABS	68,725			(468	)		—			—
	CMBS	100,396			(2,950	)		6,298			(516	)
	RMBS	268,943			(10,031	)		2,670			(260	)
	Total fixed income securities	1,410,679			(49,010	)		40,731			(2,865	)
	Equity securities	1,124			(96	)		—			—
	Subtotal	$	1,411,803		(49,106	)		40,731			(2,865	)
		Less than 12 months									12 months or longer
	($ in thousands)	Fair			Unrealized			Unrecognized			Fair			Unrealized		Unrecognized
		Value			Losses1			Gains2			Value			Losses1		Gains2
	HTM securities
	Obligations of states and political subdivisions	$	65		(5	)		5			441			(20	)	14
	ABS	—			—			—			2,490			(655	)	621
	Subtotal	65			(5	)		5			2,931			(675	)	635
	Total AFS and HTM	$	1,411,868		(49,111	)		5			43,662			(3,540	)	635
	1 Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI.  In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.
	2 Unrecognized gains represent fair value fluctuations from the later of:  (i) the date a security is designated as HTM; or (ii) the date that an OTTI charge is recognized on an HTM security.
Schedule Of The Number Of Securities In An Unrealized Unrecognized Loss Position	'
	($ in thousands)
	September 30, 2014					December 31, 2013
	Number of	% of Market/Book	Unrealized/			Number of		% of	Unrealized/
	Issues		Unrecognized Loss			Issues		Market/Book	Unrecognized Loss
	404	80% - 99%	$	16,417		556		80% - 99%	$	51,835
	2	60% - 79%	2,840			1		60% - 79%	176
	—	40% - 59%	—			—		40% - 59%	—
	—	20% - 39%	—			—		20% - 39%	—
	—	0% - 19%	—			—		0% - 19%	—
			$	19,257					$	52,011
Schedule Of Other Investment Portfolio By Strategy And Remaining Commitment Amount Associated With Each Strategy	'
	Other Investments	Carrying Value						September 30,
								2014
	($ in thousands)	September 30,			December 31,			Remaining Commitment
		2014			2013
	Alternative Investments
	Secondary private equity	$	23,064		25,618			6,978
	Private equity	21,569			20,192			9,181
	Energy/power generation	16,659			17,361			6,984
	Mezzanine financing	11,273			12,738			13,774
	Real estate	11,212			11,698			10,061
	Distressed debt	9,205			11,579			2,981
	Venture capital	7,115			7,025			350
	Total alternative investments	100,097			106,211			50,309
	Other securities	6,451			1,664			—
	Total other investments	$	106,548		107,875			50,309
Schedule Of Aggregated Summarized Income Statement Financial Information For Partnerships In Our Alternative Investment Portfolio	'
	Income Statement Information	Quarter ended September 30,1						Nine Months ended September 30,2
	($ in millions)	2014			2013			2014				2013
	Net investment income	$	81.3		97.8			$	167			352.8
	Realized (losses) gains	(26.1		)	162.8			171.5				762.5
	Net change in unrealized appreciation	628.6			104.8			1,471.00				85.9
	Net income	$	683.8		365.4			$	1,809.50			1,201.20
	Selective’s insurance subsidiaries’ other investments income	$	3.9		2.6			$	12.7			10.1
	1 The majority of these results are for the second quarter of each respective year.
	2 The majority of these results are for the nine months ended June 30 of each respective year.
Schedule Of Securities Pledged As Collateral	'
	($ in millions)	FHLBI Collateral			Reinsurance Collateral			State and Regulatory Deposits			Total
	U.S. government and government agencies	$	22.8		—			25.6			48.4
	Obligations of states and political subdivisions	—			5.7			—			5.7
	Corporate securities	—			5.3			—			5.3
	ABS	—			2			—			2
	CMBS	1.2			—			—			1.2
	RMBS	37.6			2.3			—			39.9
	Total pledged as collateral	$	61.6		15.3			25.6			102.5
Schedule of Net Investment Income Earned	'
		Quarter ended September 30,						Nine Months ended September 30,
	($ in thousands)	2014			2013			2014				2013
	Fixed income securities	$	30,706		30,569			$	95,515			$	90,956
	Equity securities	1,909			1,341			5,094				4,422
	Short-term investments	15			21			48				102
	Other investments	3,906			2,639			12,677				10,110
	Investment expenses	(2,244		)	(2,113	)		(6,734		)		(6,260		)
	Net investment income earned	$	34,292		32,457			106,600				99,330
Schedule of OTTI By Asset Type	'
	Third Quarter 2013	Gross			Included in Other Comprehensive Income ("OCI")			Recognized in Earnings
	($ in thousands)
	AFS securities
	Equity securities	$	680		—			680
	OTTI losses	$	680		—			680
	Nine Months 2014	Gross			Included in OCI			Recognized in
	($ in thousands)							Earnings
	AFS securities
	Equity securities	$	1,382		—			1,382
	OTTI losses	$	1,382		—			1,382
	Nine Months 2013	Gross			Included in OCI			Recognized in Earnings
	($ in thousands)
	HTM fixed income securities
	ABS	$	(44	)	(47	)		3
	Total HTM fixed income securities	(44		)	(47	)		3
	AFS fixed income securities
	RMBS	(22		)	(30	)		8
	Total AFS fixed income securities	(22		)	(30	)		8
	Equity securities	1,326			—			1,326
	Total AFS securities	1,304			(30	)		1,334
	Other investments	1,847			—			1,847
	OTTI losses	$	3,107		(77	)		3,184
Schedule of Gross Credit Loss Impairments on Fixed Maturity Securities for Which a Portion of the OTTI Charge was Recognized in OCI	'
		Quarter ended September 30,
	($ in thousands)	2014			2013
	Balance, beginning of period	$	5,534		7,488
	Addition for the amount related to credit loss for which an OTTI was not previously recognized	—			—
	Reductions for securities sold during the period	(90		)	—
	Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost	—			—
	Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected	—			—
	Additional increases to the amount related to credit loss for which an OTTI was previously recognized	—			—
	Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected	—			—
	Balance, end of period	$	5,444		7,488
		Nine Months ended September 30,
	($ in thousands)	2014			2013
	Balance, beginning of period	$	7,488		7,477
	Addition for the amount related to credit loss for which an OTTI was not previously recognized	—			—
	Reductions for securities sold during the period	(2,044		)	—
	Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost	—			—
	Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected	—			—
	Additional increases to the amount related to credit loss for which an OTTI was previously recognized	—			11
	Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected	—			—
	Balance, end of period	$	5,444		7,488
Schedule of Components of Net Realized Gains Excluding OTTI Charges	'
		Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)	2014			2013		2014			2013
	HTM fixed income securities
	Gains	$	—		32		3			35
	Losses	(4		)	(37	)	(18	)		(86	)
	AFS fixed income securities
	Gains	695			662		1,633			2,580
	Losses	(29		)	(31	)	(172	)		(330	)
	AFS equity securities
	Gains	14,576			13,801		27,255			24,272
	Losses	(8		)	(236	)	(332	)		(407	)
	Other investments
	Gains	1			—		1			—
	Losses	—			(80	)	—			(940	)
	Total other net realized investment gains	15,231			14,111		28,370			25,124
	Total OTTI charges recognized in earnings	—			(680	)	(1,382	)		(3,184	)
	Total net realized gains	$	15,231		13,431		26,988			21,940
Held To Maturity Fixed Income Securities [Member]	'
Investments [Line Items]	'
Schedule Of Fixed Maturity Securities By Contractual Maturities	'
	($ in thousands)	Carrying Value			Fair Value
	Due in one year or less	$	99,364		100,786
	Due after one year through five years	220,937			235,038
	Due after five years through 10 years	15,781			18,366
	Total HTM fixed income securities	$	336,082		354,190
AFS Fixed Income Securities [Member]	'
Investments [Line Items]	'
Schedule Of Fixed Maturity Securities By Contractual Maturities	'
	($ in thousands)	Fair Value
	Due in one year or less	$	435,053
	Due after one year through five years	1,915,327
	Due after five years through 10 years	1,507,315
	Due after 10 years	109,943
	Total AFS fixed income securities	$	3,967,638

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Schedule of The Carrying Amounts and Estimated Fair Values of Financial Instruments	'
			September 30, 2014						December 31, 2013
	($ in thousands)		Carrying Amount			Fair			Carrying Amount			Fair
						Value						Value
	Financial Assets
	Fixed income securities:
	HTM		$	336,082		354,190			392,879			416,981
	AFS		3,967,638			3,967,638			3,715,536			3,715,536
	Equity securities, AFS		211,266			211,266			192,771			192,771
	Short-term investments		181,593			181,593			174,251			174,251
	Financial Liabilities
	Notes payable:
	2.90% borrowings from FHLBI		13,000			13,085			13,000			13,319
	1.25% borrowings from FHLBI		45,000			45,220			45,000			45,259
	7.25% Senior Notes		49,896			56,970			49,916			50,887
	6.70% Senior Notes		99,398			110,310			99,498			98,247
	5.875% Senior Notes		185,000			179,598			185,000			146,298
	Total notes payable		$	392,294		405,183			392,414			354,010
Schedule of Quantitative Disclosures of Our Financial Assets That Were Measured At Fair Value	'
	September 30, 2014					Fair Value Measurements Using
	($ in thousands)		Assets			Quoted Prices in			Significant Other			Significant Unobservable
			Measured at			Active Markets for			Observable			Inputs
			Fair Value			Identical Assets/			Inputs			(Level 3)
			at 9/30/2014			Liabilities (Level 1)1			(Level 2)1
	Description
	Measured on a recurring basis:
	AFS:
	U.S. government and government agencies		$	151,689		51,467			100,222			—
	Foreign government		27,867			—			27,867			—
	Obligations of states and political subdivisions		1,229,234			—			1,229,234			—
	Corporate securities		1,763,230			—			1,763,230			—
	ABS		146,966			—			146,966			—
	CMBS		165,518			—			165,518			—
	RMBS		483,134			—			483,134			—
	Total AFS fixed income securities		3,967,638			51,467			3,916,171			—
	Equity securities		211,266			208,366			—			2,900
	Total AFS Securities		4,178,904			259,833			3,916,171			2,900
	Short-term investments		181,593			181,593			—			—
	Total assets measured at fair value		$	4,360,497		441,426			3,916,171			2,900
	1	There were no transfers of securities between Level 1 and Level 2.
	December 31, 2013					Fair Value Measurements Using
	($ in thousands)		Assets			Quoted Prices in			Significant			Significant Unobservable
			Measured at			Active Markets for			Other Observable			Inputs
			Fair Value			Identical Assets/Liabilities			Inputs			(Level 3)
			at 12/31/13			(Level 1)1			(Level 2)1
	Description
	Measured on a recurring basis:
	AFS:
	U.S. government and government agencies		$	173,375		52,153			121,222			—
	Foreign government		30,615			—			30,615			—
	Obligations of states and political subdivisions		951,624			—			951,624			—
	Corporate securities		1,734,883			—			1,734,883			—
	ABS		140,896			—			140,896			—
	CMBS		171,284			—			171,284			—
	RMBS		512,859			—			512,859			—
	Total AFS fixed income securities		3,715,536			52,153			3,663,383			—
	Equity securities		192,771			189,871			—			2,900
	Total AFS Securities		3,908,307			242,024			3,663,383			2,900
	Short-term investments		174,251			174,251			—			—
	Total assets measured at fair value		$	4,082,558		416,275			3,663,383			2,900
	1	There were no transfers of securities between Level 1 and Level 2.
Schedule of Summary of the Changes in Fair Value of Securities measured Using Level 3 Inputs	'
	31-Dec-13
	($ in thousands)		Government			Corporate				ABS			CMBS			Equity			Receivable for			Total
																			Proceeds
																			Related to Sale
																			of Selective HR Solutions ("Selective HR")
	Fair value, December 31, 2012		$	19,789		2,946				6,068			7,162			3,607			2,705			42,277
	Total net (losses) gains for the period included in:
	OCI1		(537		)	(7		)		(74		)	772			3,935			—			4,089
	Net income2,3		(76		)	—				—			361			—			(1,480		)	(1,195		)
	Purchases		—			—				—			—			—			—			—
	Sales		—			—				—			—			—			—			—
	Issuances		—			—				—			—			—			—			—
	Settlements		(1,847		)	(168		)		—			(2,420		)	—			(225		)	(4,660		)
	Transfers into Level 3		—			—				—			—			—			—			—
	Transfers out of Level 3		(17,329		)	(2,771		)		(5,994		)	(5,875		)	(4,642		)	(1,000		)	(37,611		)
	Fair value, December 31, 2013		$	—		$	—			$	—		$	—		$	2,900		$	—		$	2,900
	1 Amounts are reported in “Unrealized holding (losses) gains arising during period” on the Consolidated Statements of Comprehensive Income in our 2013 Annual Report.
	2 Amounts are reported in “Net realized gains” for realized gains and losses and “Net investment income earned” for amortization of securities on the Consolidated Statements of Income in our 2013 Annual Report.
	3 For the receivable related to the sale of Selective HR, amounts in "Loss on disposal of discontinued operations, net of tax" relate to an impairment charge and amounts in "Other income" relate to interest accretion on the Consolidated Statements of Income in our 2013 Annual Report.
Schedule of Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value	'
	:
	September 30, 2014					Fair Value Measurements Using
	($ in thousands)		Assets/			Quoted Prices in			Significant Other			Significant
			Liabilities			Active Markets for			Observable			Unobservable
			Disclosed at			Identical Assets/			Inputs			Inputs
			Fair Value at 9/30/2014			Liabilities			(Level 2)			(Level 3)
						(Level 1)
	Financial Assets
	HTM:
	Foreign government		$	5,407		—			5,407			—
	Obligations of states and political subdivisions		317,609			—			317,609			—
	Corporate securities		22,726			—			22,726			—
	ABS		3,124			—			3,124			—
	CMBS		5,324			—			5,324			—
	Total HTM fixed income securities		$	354,190		—			354,190			—
	Financial Liabilities
	Notes payable:
	2.90% borrowings from FHLBI		$	13,085		—			13,085			—
	1.25% borrowings from FHLBI		45,220			—			45,220			—
	7.25% Senior Notes		56,970			—			56,970			—
	6.70% Senior Notes		110,310			—			110,310			—
	5.875% Senior Notes		179,598			179,598			—			—
	Total notes payable		$	405,183		179,598			225,585			—
	December 31, 2013					Fair Value Measurements Using
	($ in thousands)		Assets/			Quoted Prices in			Significant Other			Significant
			Liabilities			Active Markets for			Observable			Unobservable
			Disclosed at			Identical Assets/			Inputs			Inputs
			Fair Value at 12/31/2013			Liabilities			(Level 2)			(Level 3)
						(Level 1)
	Financial Assets
	HTM:
	Foreign government		$	5,591		—			5,591			—
	Obligations of states and political subdivisions		369,756			—			369,756			—
	Corporate securities		30,274			—			30,274			—
	ABS		3,415			—			3,415			—
	CMBS		7,945			—			7,945			—
	Total HTM fixed income securities		$	416,981		—			416,981			—
	Financial Liabilities
	Notes payable:
	2.90% borrowings from FHLBI		$	13,319		—			13,319			—
	1.25% borrowings from FHLBI		45,259			—			45,259			—
	7.25% Senior Notes		50,887			—			50,887			—
	6.70% Senior Notes		98,247			—			98,247			—
	5.875% Senior Notes		146,298			146,298			—			—
	Total notes payable		$	354,010		146,298			207,712			—

Reinsurance_Tables

Reinsurance (Tables)	9 Months Ended
	Sep. 30, 2014
Reinsurance Disclosures [Abstract]	'
Schedule of List Of Direct, Assumed, And Ceded Reinsurance Amounts	'
		Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)	2014			2013		2014		2013
	Premiums written:
	Direct	$	592,858		570,849		1,723,063		1,650,855
	Assumed	5,780			22,053		19,467		34,913
	Ceded	(103,517		)	(100,154	)	(290,836	)	(280,719	)
	Net	$	495,121		492,748		1,451,694		1,405,049
	Premiums earned:
	Direct	$	548,734		518,307		1,630,347		1,516,454
	Assumed	6,789			11,066		27,359		32,480
	Ceded	(92,884		)	(91,805	)	(274,947	)	(264,174	)
	Net	$	462,639		437,568		1,382,759		1,284,760
	Loss and loss expense incurred:
	Direct	$	304,525		350,648		995,581		1,055,248
	Assumed	5,362			7,264		20,218		22,758
	Ceded	(38,955		)	(74,595	)	(126,526	)	(245,246	)
	Net	$	270,932		283,317		889,273		832,760
Schedule of Ceded Premiums and Losses Related to Flood Operations	'
	Ceded to NFIP	Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)	2014			2013		2014		2013
	Ceded premiums written	$	(69,922	)	(64,196	)	(193,000	)	(183,364	)
	Ceded premiums earned	(60,761		)	(57,920	)	(178,260	)	(169,697	)
	Ceded loss and loss expense incurred	(14,008		)	(34,879	)	(48,099	)	(162,780	)

Segment_Information_Tables

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Schedule Of Revenue From Continuing Operations By Segment	'
	Revenue by Segment	Quarter ended					Nine Months ended
		September 30,					September 30,
	($ in thousands)	2014			2013		2014			2013
	Standard Insurance Operations:
	Net premiums earned:
	Commercial automobile	$	83,536		79,138		249,224			230,191
	Workers compensation	66,732			66,510		205,137			197,449
	General liability	110,894			100,925		331,303			298,394
	Commercial property	61,304			57,004		182,716			165,356
	Businessowners’ policies	21,649			19,629		63,797			56,794
	Bonds	4,791			4,705		14,281			14,244
	Other	3,237			3,051		9,633			9,036
	Total Standard Commercial Lines	352,143			330,962		1,056,091			971,464
	Personal automobile	37,695			38,513		113,943			115,432
	Homeowners	33,957			32,374		100,831			95,211
	Other	2,725			3,827		8,965			10,655
	Total Standard Personal Lines	74,377			74,714		223,739			221,298
	Total Standard Insurance Operations net premiums earned	426,520			405,676		1,279,830			1,192,762
	Miscellaneous income	3,196			3,342		14,923			9,590
	Total Standard Insurance Operations revenue	429,716			409,018		1,294,753			1,202,352
	E&S Insurance Operations:
	Net premiums earned	36,119			31,892		102,929			91,998
	Investments:
	Net investment income	34,292			32,457		106,600			99,330
	Net realized investment gains	15,231			13,431		26,988			21,940
	Total investment revenues	49,523			45,888		133,588			121,270
	Total all segments	515,358			486,798		1,531,270			1,415,620
	Other income	—			15		8			87
	Total revenues from continuing operations	$	515,358		486,813		1,531,278			1,415,707
Schedule of Income from Continuing Operations Before Federal Income Tax	'
	Income from Continuing Operations before Federal Income Tax	Quarter ended September 30,					Nine Months ended September 30,
	($ in thousands)	2014			2013		2014				2013
	Standard Insurance Operations:
	Commercial Lines underwriting gain	$	27,771		8,776		$	39,844			24,621
	Personal Lines underwriting gain	8,037			1,362		95				4,360
	Total Standard Insurance Operations underwriting gain, before federal income tax	35,808			10,138		39,939				28,981
	GAAP combined ratio	91.6		%	97.5		96.9		%		97.6
	Statutory combined ratio	90.5		%	96		96.3		%		96.6
	E&S Insurance Operations:
	Underwriting (loss) gain	(1,371		)	13		(433		)		(2,186	)
	GAAP combined ratio	103.8		%	100		100.4		%		102.4
	Statutory combined ratio	102.9		%	100.5		100.3		%		101.9
	Investments:
	Net investment income	34,292			32,457		106,600				99,330
	Net realized investment gains	15,231			13,431		26,988				21,940
	Total investment income, before federal income tax	49,523			45,888		133,588				121,270
	Tax on investment income	13,858			12,648		36,374				31,960
	Total investment income, after federal income tax	35,665			33,240		97,214				89,310
Schedule of Reconciliation of Segment Results to Income From Continuing Operations, Before Federal Income Tax	'
	Reconciliation of Segment Results to Income from Continuing Operations,	Quarter ended					Nine Months ended
	before Federal Income Tax	September 30,					September 30,
	($ in thousands)	2014			2013		2014				2013
	Standard Insurance Operations underwriting gain, before federal income tax	$	35,808		10,138		$	39,939			28,981
	E&S Insurance Operations underwriting (loss) gain, before federal income tax	(1,371		)	13		(433		)		(2,186	)
	Investment income, before federal income tax	49,523			45,888		133,588				121,270
	Total all segments	83,960			56,039		173,094				148,065
	Interest expense	(5,558		)	(5,570	)	(16,544		)		(16,971	)
	General corporate and other expenses	(3,076		)	(5,984	)	(16,619		)		(21,540	)
	Income from continuing operations, before federal income tax	$	75,326		44,485		$	139,931			109,554

Retirement_Plans_Table

Retirement Plans (Table)	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Schedule of Components Of Net Periodic Benefit Cost And Other Amounts Recognized In Other Comprehensive Income	'
		Retirement Income Plan							Retirement Life Plan
		Quarter ended September 30,							Quarter ended September 30,
	($ in thousands)	2014				2013			2014		2013
	Components of Net Periodic Benefit Cost:
	Net Periodic Benefit Cost:
	Service cost	$	1,627			1,857			—		—
	Interest cost	3,253				3,053			73		69
	Expected return on plan assets	(3,919		)		(3,986	)		—		—
	Amortization of unrecognized net actuarial loss	367				772			14		18
	Total net periodic cost	$	1,328			1,696			87		87
		Retirement Income Plan							Retirement Life Plan
		Nine Months ended September 30,							Nine Months ended September 30,
	($ in thousands)	2014				2013			2014		2013
	Components of Net Periodic Benefit Cost:
	Net Periodic Benefit Cost:
	Service cost	$	4,880			6,163			—		—
	Interest cost	9,760				9,407			219		208
	Expected return on plan assets	(11,756		)		(11,819	)		—		—
	Amortization of unrecognized prior service	—				10			—		—
	Amortization of unrecognized net actuarial loss	1,102				3,366			40		53
	Curtailment expense	—				16			—		—
	Total net periodic cost	$	3,986			7,143			259		261
Schedule Of Weighted-Average Expense Assumptions	'
		Retirement Income Plan					Retirement Life Plan
		Nine Months ended September 30,					Nine Months ended September 30,
		2014			2013		2014			2013
	Weighted-Average Expense Assumptions:
	Discount rate	5.16	%		4.66		4.85	%		4.42
	Expected return on plan assets	6.92			7.4		—			—
	Rate of compensation increase	4			4		—			—

Comprehensive_Income_Tables

Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2014
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]	'
Schedule of Components of Comprehensive Income-Gross and Net of Tax	'
	Third Quarter 2014
	($ in thousands)		Gross				Tax			Net
	Net income		$	75,326			22,164			53,162
	Components of OCI:
	Unrealized losses on investment securities:
	Unrealized holding losses during the period		(13,831		)		(4,843	)		(8,988	)
	Amounts reclassified into net income:
	HTM securities		(373		)		(130	)		(243	)
	Non-credit OTTI		1,200				420			780
	Realized gains on AFS securities		(16,435		)		(5,752	)		(10,683	)
	Net unrealized losses		(29,439		)		(10,305	)		(19,134	)
	Defined benefit pension and post-retirement plans:
	Amounts reclassified into net income:
	Net actuarial loss		381				134			247
	Defined benefit pension and post-retirement plans		381				134			247
	Other comprehensive loss		(29,058		)		(10,171	)		(18,887	)
	Comprehensive income		$	46,268			11,993			34,275
	Third Quarter 2013
	($ in thousands)		Gross				Tax			Net
	Net income		$	44,485			11,832			32,653
	Components of OCI:
	Unrealized losses on investment securities:
	Unrealized holding gains during the period		9,820				3,437			6,383
	Amounts reclassified into net income:
	HTM securities		(472		)		(165	)		(307	)
	Non-credit OTTI		1				—			1
	Realized gains on AFS securities		(13,516		)		(4,731	)		(8,785	)
	Net unrealized losses		(4,167		)		(1,459	)		(2,708	)
	Defined benefit pension and post-retirement plans:
	Amounts reclassified into net income:
	Net actuarial loss		790				277			513
	Defined benefit pension and post-retirement plans		790				277			513
	Other comprehensive loss		(3,377		)		(1,182	)		(2,195	)
	Comprehensive loss		$	41,108			10,650			30,458
	Nine Months 2014
	($ in thousands)		Gross				Tax			Net
	Net income		$	139,931			39,454			100,477
	Components of OCI:
	Unrealized gains on investment securities:
	Unrealized holding gains during the period		64,255				22,488			41,767
	Amounts reclassified into net income:
	HTM securities		(1,050		)		(367	)		(683	)
	Non-credit OTTI		1,669				584			1,085
	Realized gains on AFS securities		(28,672		)		(10,035	)		(18,637	)
	Net unrealized gains		36,202				12,670			23,532
	Defined benefit pension and post-retirement plans:
	Amounts reclassified into net income:
	Net actuarial loss		1,142				400			742
	Defined benefit pension and post-retirement plans		1,142				400			742
	Other comprehensive income		37,344				13,070			24,274
	Comprehensive income		$	177,275			52,524			124,751
	Nine Months 2013
	($ in thousands)		Gross				Tax			Net
	Net income		$	108,019			26,936			81,083
	Components of OCI:
	Unrealized losses on investment securities:
	Unrealized holding losses during the period		(77,810		)		(27,234	)		(50,576	)
	Non-credit OTTI recognized in OCI		77				27			50
	Amounts reclassified into net income:
	HTM securities		(1,803		)		(631	)		(1,172	)
	Non-credit OTTI		14				5			9
	Realized gains on AFS securities		(24,780		)		(8,673	)		(16,107	)
	Net unrealized losses		(104,302		)		(36,506	)		(67,796	)
Defined benefit pension and post-retirement plans:
Net actuarial gains		44,000				15,400			28,600
Amounts reclassified into net income:
Net actuarial loss		3,419				1,197			2,222
Prior service cost		10				4			6
Curtailment expense		16				5			11
Defined benefit pension and post-retirement plans		47,445				16,606			30,839
Other comprehensive loss		(56,857		)		(19,900	)		(36,957	)
Comprehensive income		$	51,162			7,036			44,126
Schedule of Components of Accumulated Other Comprehensive Income	'
	September 30, 2014		Net Unrealized (Loss) Gain on Investment Securities
	($ in thousands)		OTTI				HTM			All			Investments		Defined Benefit		Total AOCI
			Related				Related			Other			Subtotal		Pension and Post-Retirement Plans
	Balance, December 31, 2013		$	(1,599	)		1,467			51,635			51,503		(26,652	)	24,851
	OCI before reclassifications		—				—			41,767			41,767		—		41,767
	Amounts reclassified from AOCI		1,085				(683	)		(18,637	)		(18,235	)	742		(17,493	)
	Net current period OCI		1,085				(683	)		23,130			23,532		742		24,274
	Balance, September 30, 2014		$	(514	)		784			74,765			75,035		(25,910	)	49,125
Schedule of Reclassifications Out Of Accumulated Other Comprehensive Income	'
		Quarter ended						Nine Months ended
		September 30,						September 30,
	($ in thousands)	2014			2013			2014			2013		Affected Line Item in the Unaudited Consolidated Statement of Income
	OTTI related
	Amortization of non-credit OTTI losses on HTM securities	—			1			—			14		Net investment income earned
	Non-credit OTTI on disposed securities	1,200			—			1,669			—		Net realized gains
		1,200			1			1,669			14		Income from continuing operations, before federal income tax
		(420	)		—			(584	)		(5	)	Total federal income tax expense
		780			1			1,085			9		Net income
	HTM related
	Unrealized losses (gains) on HTM disposals	12			(19	)		87			(170	)	Net realized gains
	Amortization of net unrealized gains on HTM securities	(385	)		(453	)		(1,137	)		(1,633	)	Net investment income earned
		(373	)		(472	)		(1,050	)		(1,803	)	Income from continuing operations, before federal income tax
		130			165			367			631		Total federal income tax expense
		(243	)		(307	)		(683	)		(1,172	)	Net income
	Realized gains and losses on AFS and OTTI
	Realized gains on AFS disposals and OTTI	(16,435	)		(13,516	)		(28,672	)		(24,780	)	Net realized gains
		(16,435	)		(13,516	)		(28,672	)		(24,780	)	Income from continuing operations, before federal income tax
		5,752			4,731			10,035			8,673		Total federal income tax expense
		(10,683	)		(8,785	)		(18,637	)		(16,107	)	Net income
	Defined benefit pension and post-retirement life plans
	Net actuarial loss	88			159			263			717		Loss and loss expense incurred
		293			631			879			2,702		Policy acquisition costs
		381			790			1,142			3,419		Income from continuing operations, before federal income tax
	Prior service cost	—			—			—			7		Loss and loss adjustment expenses
		—			—			—			3		Policy acquisition costs
		—			—			—			10		Income from continuing operations, before federal income tax
	Curtailment expense	—			—			—			16		Policy acquisition costs
		—			—			—			16		Income from continuing operations, before federal income tax
	Total defined benefit pension and post-retirement life	381			790			1,142			3,445		Income from continuing operations, before federal income tax
		(134	)		(277	)		(400	)		(1,206	)	Total federal income tax expense
		247			513			742			2,239		Net income
	Total reclassifications for the period	(9,899	)		(8,578	)		(17,493	)		(15,031	)	Net income

Organization_Narrative_Details

Organization (Narrative) (Details)	9 Months Ended
	Sep. 30, 2014
Number of Operating Segments	3

Statements_of_Cash_Flow_Cash_F

Statements of Cash Flow (Cash Flow Supplemental Disclosures) (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Interest	$14,089,000	$13,325,000
Federal income tax	4,699,000	17,000,000
Stock Split Related To Equity Securities, AFS	334,000	0
Assets acquired under capital lease arrangements	4,853,000	2,290,000
AFS Fixed Maturity Securities [Member]	'	'
Tax-free exchange of fixed maturity security	14,954,000	23,733,000
Held-to-maturity Securities [Member]	'	'
Tax-free exchange of fixed maturity security	4,288,000	15,820,000
National Flood Insurance Program [Member]	'	'
Restricted Cash	$8,100,000	'

Investments_HeldToMaturity_Sec

Investments (Held-To-Maturity Securities Disclosure) (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	$334,875	$390,622
Net Unrealized Gains (Losses)	1,207	2,257
Carrying Value	336,082	392,879
Unrecognized Holding Gains	18,109	24,102
Unrecognized Holding Losses	-1	0
HTM, Fair Value	354,190	416,981
Held To Maturity securities average duration	'2 years 0 months 0 days	'
Foreign Government [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	5,292	5,292
Net Unrealized Gains (Losses)	68	131
Carrying Value	5,360	5,423
Unrecognized Holding Gains	47	168
Unrecognized Holding Losses	0	0
HTM, Fair Value	5,407	5,591
Obligations of States and Political Subdivisions [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	301,216	348,109
Net Unrealized Gains (Losses)	2,472	4,013
Carrying Value	303,688	352,122
Unrecognized Holding Gains	13,921	17,634
Unrecognized Holding Losses	0	0
HTM, Fair Value	317,609	369,756
Corporate Securities [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	20,303	28,174
Net Unrealized Gains (Losses)	-325	-346
Carrying Value	19,978	27,828
Unrecognized Holding Gains	2,749	2,446
Unrecognized Holding Losses	-1	0
HTM, Fair Value	22,726	30,274
Asset-Backed Securities [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	3,111	3,413
Net Unrealized Gains (Losses)	-530	-655
Carrying Value	2,581	2,758
Unrecognized Holding Gains	543	657
Unrecognized Holding Losses	0	0
HTM, Fair Value	3,124	3,415
Commercial Mortgage Backed Securities [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	4,953	5,634
Net Unrealized Gains (Losses)	-478	-886
Carrying Value	4,475	4,748
Unrecognized Holding Gains	849	3,197
Unrecognized Holding Losses	0	0
HTM, Fair Value	$5,324	$7,945

Investments_AvailableForSale_S

Investments (Available-For-Sale Securities Disclosure) (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	$4,064,671,000		$3,831,327,000
Unrealized Gains	133,475,000		128,951,000
Unrealized Losses	-19,242,000		-51,971,000
Total AFS securities	4,178,904,000		3,908,307,000
AFS Fixed Income Securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	3,884,252,000		3,675,977,000
Unrealized Gains	98,678,000		91,434,000
Unrealized Losses	-15,292,000		-51,875,000
Total AFS securities	3,967,638,000		3,715,536,000
AFS Fixed Income Securities [Member] | U.S. Government and Government Agencies [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	143,742,000		163,218,000
Unrealized Gains	8,210,000		10,661,000
Unrealized Losses	-263,000		-504,000
Total AFS securities	151,689,000		173,375,000
AFS Fixed Income Securities [Member] | Foreign Government [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	27,041,000		29,781,000
Unrealized Gains	832,000		906,000
Unrealized Losses	-6,000		-72,000
Total AFS securities	27,867,000		30,615,000
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	1,196,478,000		946,455,000
Unrealized Gains	34,533,000		25,194,000
Unrealized Losses	-1,777,000		-20,025,000
Total AFS securities	1,229,234,000		951,624,000
AFS Fixed Income Securities [Member] | Corporate Securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	1,725,290,000		1,707,928,000
Unrealized Gains	44,571,000		44,004,000
Unrealized Losses	-6,631,000		-17,049,000
Total AFS securities	1,763,230,000		1,734,883,000
AFS Fixed Income Securities [Member] | Asset-Backed Securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	146,557,000		140,430,000
Unrealized Gains	791,000		934,000
Unrealized Losses	-382,000		-468,000
Total AFS securities	146,966,000		140,896,000
AFS Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	164,934,000	[1]	172,288,000	[1]
Unrealized Gains	2,077,000	[1]	2,462,000	[1]
Unrealized Losses	-1,493,000	[1]	-3,466,000	[1]
Total AFS securities	165,518,000	[1]	171,284,000	[1]
Government guaranteed agency securities fair value	17,600,000		30,000,000
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	480,210,000	[2]	515,877,000	[2]
Unrealized Gains	7,664,000	[2]	7,273,000	[2]
Unrealized Losses	-4,740,000	[2]	-10,291,000	[2]
Total AFS securities	483,134,000	[2]	512,859,000	[2]
Government guaranteed agency securities fair value	35,900,000		55,200,000
Equity Securities [Member]	'		'
Schedule of Available-for-sale Securities [Line Items]	'		'
Cost/Amortized Cost	180,419,000		155,350,000
Unrealized Gains	34,797,000		37,517,000
Unrealized Losses	-3,950,000		-96,000
Total AFS securities	$211,266,000		$192,771,000
[1]	CMBS includes government guaranteed agency securities with a fair value of $17.6 million at September 30, 2014 and $30.0 million at December 31, 2013.
[2]	RMBS includes government guaranteed agency securities with a fair value of $35.9 million at September 30, 2014 and $55.2 million at December 31, 2013.

Investments_Fair_Value_and_Gro

Investments (Fair Value and Gross Pre-Tax Net Unrealized Unrecognized Loss of Securities By Length of Time) (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
AFS Fair Value, Less than 12 months	$532,683		$1,411,803
AFS Unrealized Losses, Less than 12 months	-6,101	[1]	-49,106	[1]
AFS Fair Value, 12 months or longer	505,310		40,731
AFS Unrealized Losses, 12 months or longer	-13,141	[1]	-2,865	[1]
HTM Fair Value, Less than 12 months	460		65
HTM Unrealized Losses, Less than 12 months	-9	[1]	-5	[1]
HTM Unrecognized Gains, Less than 12 months	8	[2]	5	[2]
HTM Fair Value, 12 months or longer	2,428		2,931
HTM Unrealized Losses, 12 months or longer	-530	[1]	-675	[1]
HTM Unrecognized Gains, 12 months or longer	516	[2]	635	[2]
Total AFS and HTM Fair Value, Less than 12 months	533,143		1,411,868
Total AFS and HTM Unrealized Losses, Less than 12 months	-6,110	[1]	-49,111	[1]
Total AFS and HTM Securities Unrecognized Gains, Less Than 12 Months	8	[2]	5	[2]
Total AFS and HTM Fair Value, 12 months or longer	507,738		43,662
Total AFS and HTM Unrealized Losses, 12 months or longer	-13,671	[1]	-3,540	[1]
Total AFS and HTM Securities Unrecognized Gains, 12 months or longer	516	[2]	635	[2]
Obligations of States and Political Subdivisions [Member]	'		'
HTM Fair Value, Less than 12 months	460		65
HTM Unrealized Losses, Less than 12 months	-9	[1]	-5	[1]
HTM Unrecognized Gains, Less than 12 months	8	[2]	5	[2]
HTM Fair Value, 12 months or longer	0		441
HTM Unrealized Losses, 12 months or longer	0	[1]	-20	[1]
HTM Unrecognized Gains, 12 months or longer	0	[2]	14	[2]
Asset-Backed Securities [Member]	'		'
HTM Fair Value, Less than 12 months	0		0
HTM Unrealized Losses, Less than 12 months	0	[1]	0	[1]
HTM Unrecognized Gains, Less than 12 months	0	[2]	0	[2]
HTM Fair Value, 12 months or longer	2,428		2,490
HTM Unrealized Losses, 12 months or longer	-530	[1]	-655	[1]
HTM Unrecognized Gains, 12 months or longer	516	[2]	621	[2]
AFS Fixed Income Securities [Member]	'		'
AFS Fair Value, Less than 12 months	497,454		1,410,679
AFS Unrealized Losses, Less than 12 months	-2,151	[1]	-49,010	[1]
AFS Fair Value, 12 months or longer	505,310		40,731
AFS Unrealized Losses, 12 months or longer	-13,141	[1]	-2,865	[1]
AFS Fixed Income Securities [Member] | U.S. Government and Government Agencies [Member]	'		'
AFS Fair Value, Less than 12 months	1,001		16,955
AFS Unrealized Losses, Less than 12 months	0	[1]	-500	[1]
AFS Fair Value, 12 months or longer	13,219		507
AFS Unrealized Losses, 12 months or longer	-263	[1]	-4	[1]
AFS Fixed Income Securities [Member] | Foreign Government [Member]	'		'
AFS Fair Value, Less than 12 months	4,755		2,029
AFS Unrealized Losses, Less than 12 months	-6	[1]	-30	[1]
AFS Fair Value, 12 months or longer	0		2,955
AFS Unrealized Losses, 12 months or longer	0	[1]	-42	[1]
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member]	'		'
AFS Fair Value, Less than 12 months	121,728		442,531
AFS Unrealized Losses, Less than 12 months	-292	[1]	-19,120	[1]
AFS Fair Value, 12 months or longer	98,944		13,530
AFS Unrealized Losses, 12 months or longer	-1,485	[1]	-905	[1]
AFS Fixed Income Securities [Member] | Corporate Debt Securities [Member]	'		'
AFS Fair Value, Less than 12 months	274,501		511,100
AFS Unrealized Losses, Less than 12 months	-1,529	[1]	-15,911	[1]
AFS Fair Value, 12 months or longer	158,127		14,771
AFS Unrealized Losses, 12 months or longer	-5,102	[1]	-1,138	[1]
AFS Fixed Income Securities [Member] | Asset-Backed Securities [Member]	'		'
AFS Fair Value, Less than 12 months	47,542		68,725
AFS Unrealized Losses, Less than 12 months	-134	[1]	-468	[1]
AFS Fair Value, 12 months or longer	14,149		0
AFS Unrealized Losses, 12 months or longer	-248	[1]	0	[1]
AFS Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member]	'		'
AFS Fair Value, Less than 12 months	16,969		100,396
AFS Unrealized Losses, Less than 12 months	-89	[1]	-2,950	[1]
AFS Fair Value, 12 months or longer	57,634		6,298
AFS Unrealized Losses, 12 months or longer	-1,404	[1]	-516	[1]
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member]	'		'
AFS Fair Value, Less than 12 months	30,958		268,943
AFS Unrealized Losses, Less than 12 months	-101	[1]	-10,031	[1]
AFS Fair Value, 12 months or longer	163,237		2,670
AFS Unrealized Losses, 12 months or longer	-4,639	[1]	-260	[1]
Equity Securities [Member]	'		'
AFS Fair Value, Less than 12 months	35,229		1,124
AFS Unrealized Losses, Less than 12 months	-3,950	[1]	-96	[1]
AFS Fair Value, 12 months or longer	0		0
AFS Unrealized Losses, 12 months or longer	$0	[1]	$0	[1]
[1]	Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI. In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.
[2]	Unrecognized gains represent fair value fluctuations from the later of: (i) the date a security is designated as HTM; or (ii) the date that an OTTI charge is recognized on an HTM security.

Investments_Number_of_Securiti

Investments (Number of Securities in an Unrealized Unrecognized Loss Position) (Details) (USD $)

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Securities

Securities

Eighty Percent to Ninety-Nine Percent [Member]

Eighty Percent to Ninety-Nine Percent [Member]

Sixty Percent to Seventy-Nine Percent [Member]

Sixty Percent to Seventy-Nine Percent [Member]

Forty Percent to Fifty-Nine Percent [Member]

Forty Percent to Fifty-Nine Percent [Member]

Twenty Percent to Thirty-Nine Percent [Member]

Twenty Percent to Thirty-Nine Percent [Member]

Zero Percent to Nineteen Percent [Member]

Zero Percent to Nineteen Percent [Member]

10 year U.S. Treasury Note [Member]

Securities

Securities

Securities

Securities

Securities

Securities

Securities

Securities

Securities

Securities

Schedule of Available-for-sale Securities [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

Number Of Securities In An Unrealized/Unrecognized Loss Position

406

557

404

556

2

1

0

0

0

0

0

0

'

Unrealized Unrecognized Loss

$19,257,000

$52,011,000

$16,417,000

$51,835,000

$2,840,000

$176,000

$0

$0

$0

$0

$0

$0

'

Decrease of Yield on 10-year U.S. Treasury Note

'

'

'

'

'

'

'

'

'

'

'

'

54

Securities In Unrealized Unrecognized Loss Position For More Than Twelve Months Unrealized Unrecognized Loss

$13,200,000

$2,900,000

'

'

'

'

'

'

'

'

'

'

'

Percentage Decline in Fair Value Percentage

3.00%

6.00%

'

'

'

'

'

'

'

'

'

'

'

Investments_HTM_Fixed_Income_S

Investments (HTM Fixed Income Securities by Contractual Maturity) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Investments [Abstract]	'	'
Due in one year or less carrying value	$99,364	'
Due after one year through five years carrying value	220,937	'
Due after five years through 10 years carrying value	15,781	'
Carrying Value	336,082	392,879
Due in one year or less fair value	100,786	'
Due after one year through five years fair value	235,038	'
Due after five years through 10 years fair value	18,366	'
HTM, Fair Value	$354,190	$416,981

Investments_AFS_Fixed_Income_s

Investments (AFS Fixed Income securities by Contractual Maturity) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Investments [Abstract]	'	'
Due in one year or less fair value	$435,053	'
Due after one year through five years fair value	1,915,327	'
Due after five years through 10 years fair value	1,507,315	'
Due after 10 years fair value	109,943	'
Total AFS fixed income securities	$3,967,638	$3,715,536

Investments_Other_Investment_P

Investments (Other Investment Portfolio by Strategy and the Remaining Commitment Amount Associated With Each Strategy) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Carrying Value	$106,548	$107,875
Other Investments [Member]	'	'
Carrying Value	106,548	107,875
Remaining Commitment	50,309	'
Alternative Investments [Member]	'	'
Carrying Value	100,097	106,211
Remaining Commitment	50,309	'
Secondary Private Equity Member | Alternative Investments [Member]	'	'
Carrying Value	23,064	25,618
Remaining Commitment	6,978	'
Private Equity [Member] | Alternative Investments [Member]	'	'
Carrying Value	21,569	20,192
Remaining Commitment	9,181	'
Energy Power Generation [Member] | Alternative Investments [Member]	'	'
Carrying Value	16,659	17,361
Remaining Commitment	6,984	'
Mezzanine Financing [Member] | Alternative Investments [Member]	'	'
Carrying Value	11,273	12,738
Remaining Commitment	13,774	'
Real estate [Member] | Alternative Investments [Member]	'	'
Carrying Value	11,212	11,698
Remaining Commitment	10,061	'
Distressed debt [Member] | Alternative Investments [Member]	'	'
Carrying Value	9,205	11,579
Remaining Commitment	2,981	'
Venture Capital [Member] | Alternative Investments [Member]	'	'
Carrying Value	7,115	7,025
Remaining Commitment	350	'
Other Securities [Member]	'	'
Carrying Value	6,451	1,664
Remaining Commitment	$0	'

Investments_Aggregated_Income_

Investments (Aggregated Income Statement Summarized Financial Information for Partnerhips in our Alternative Investment Portfolio) (Details) (USD $)	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Schedule of Equity Method Investments [Line Items]	'		'		'		'
Net investment income earned	$34,292,000		$32,457,000		$106,600,000		$99,330,000
Alternative Investments [Member]	'		'		'		'
Schedule of Equity Method Investments [Line Items]	'		'		'		'
Net investment income earned	3,900,000	[1]	2,600,000	[1]	12,700,000	[2]	10,100,000	[2]
Investments accounted for under the equity method [Member]	'		'		'		'
Schedule of Equity Method Investments [Line Items]	'		'		'		'
Net Investment Income	81,300,000	[1]	97,800,000	[1]	167,000,000	[2]	352,800,000	[2]
Realized gains	-26,100,000	[1]	162,800,000	[1]	171,500,000	[2]	762,500,000	[2]
Net change in unrealized appreciation (depreciation)	628,600,000	[1]	104,800,000	[1]	1,471,000,000	[2]	85,900,000	[2]
Net income	$683,800,000	[1]	$365,400,000	[1]	$1,809,500,000	[2]	$1,201,200,000	[2]
[1]	The majority of these results are for the second quarter of each respective year.
[2]	The majority of these results are for the nine months ended June 30 of each respective year.

Investments_Investments_Pledge

Investments (Investments Pledged as Collateral) (Details) (USD $)	Sep. 30, 2014
In Millions, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	$61.60
Securities Pledged As Collateral For Reinsurance Obligations	15.3
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	25.6
Securities Pledged As Collateral	102.5
Outstanding Borrowing With The Federal Home Loan Bank Of Indianapolis	58
U.S. Government and Government Agencies [Member]	'
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	22.8
Securities Pledged As Collateral For Reinsurance Obligations	0
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	25.6
Securities Pledged As Collateral	48.4
Obligations of States and Political Subdivisions [Member]	'
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	5.7
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	5.7
Corporate Securities [Member]	'
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	5.3
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	5.3
Asset-Backed Securities [Member]	'
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	2
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	2
Commercial Mortgage Backed Securities [Member]	'
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	1.2
Securities Pledged As Collateral For Reinsurance Obligations	0
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	1.2
Residential Mortgage Backed Securities [Member]	'
Schedule of Available-for-sale Securities [Line Items]	'
Fixed Income Securities Pledged For FHLBI Collateral	37.6
Securities Pledged As Collateral For Reinsurance Obligations	2.3
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	$39.90

Investments_Net_Investment_Inc

Investments (Net Investment Income) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net Investment Income [Line Items]	'	'	'	'
Net investment income earned	$34,292	$32,457	$106,600	$99,330
Fixed Income Securities [Member]	'	'	'	'
Net Investment Income [Line Items]	'	'	'	'
Net investment income earned	30,706	30,569	95,515	90,956
Equity Securities [Member]	'	'	'	'
Net Investment Income [Line Items]	'	'	'	'
Net investment income earned	1,909	1,341	5,094	4,422
Short-Term Investments [Member]	'	'	'	'
Net Investment Income [Line Items]	'	'	'	'
Net investment income earned	15	21	48	102
Other Investments [Member]	'	'	'	'
Net Investment Income [Line Items]	'	'	'	'
Net investment income earned	3,906	2,639	12,677	10,110
Investment Expenses [Member]	'	'	'	'
Net Investment Income [Line Items]	'	'	'	'
Net investment income earned	($2,244)	($2,113)	($6,734)	($6,260)

Investments_OTTI_by_Asset_Type

Investments (OTTI by Asset Type) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
OTTI Losses Gross	$0	$680	$1,382	$3,107
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	0	0	0	-77
OTTI Losses Recognized in Earnings	0	680	1,382	3,184
Other Investments [Member]	'	'	'	'
OTTI Losses Gross	'	'	'	1,847
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	'	'	0
OTTI Losses Recognized in Earnings	'	'	'	1,847
Held-to-maturity Securities [Member]	'	'	'	'
OTTI Losses Gross	'	'	'	-44
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	'	'	-47
OTTI Losses Recognized in Earnings	'	'	'	3
Held-to-maturity Securities [Member] | Asset-Backed Securities [Member]	'	'	'	'
OTTI Losses Gross	'	'	'	-44
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	'	'	-47
OTTI Losses Recognized in Earnings	'	'	'	3
AFS Fixed Income Securities [Member]	'	'	'	'
OTTI Losses Gross	'	'	'	-22
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	'	'	-30
OTTI Losses Recognized in Earnings	'	'	'	8
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member]	'	'	'	'
OTTI Losses Gross	'	'	'	-22
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	'	'	-30
OTTI Losses Recognized in Earnings	'	'	'	8
Total AFS Securities [Member]	'	'	'	'
OTTI Losses Gross	'	'	'	1,304
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	'	'	-30
OTTI Losses Recognized in Earnings	'	'	'	1,334
Total AFS Securities [Member] | Equity Securities [Member]	'	'	'	'
OTTI Losses Gross	'	680	1,382	1,326
Other-than-temporary impairments on fixed income securities recognized in other comprehensive income	'	0	0	0
OTTI Losses Recognized in Earnings	'	$680	$1,382	$1,326

Investments_Gross_Credit_Loss_

Investments (Gross Credit Loss Impairments of Fixed Maturity Securities for Which a Portion of the OTTI Charge was Recognized in OCI) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Investments [Abstract]	'	'	'	'
Balance, beginning of period	$5,534	$7,488	$7,488	$7,477
Addition for the amount related to credit loss for which an OTTI was not previously recognized	0	0	0	0
Reductions for securities sold during the period	-90	0	-2,044	0
Reductions for securities for which the amount previously recognized in OCI was recognized in earnings because of intention or potential requirement to sell before recovery of amortized cost	0	0	0	0
Reductions for securities for which the entire amount previously recognized in OCI was recognized in earnings due to a decrease in cash flows expected	0	0	0	0
Additional increases to the amount related to credit loss for which an OTTI was previously recognized	0	0	0	11
Accretion of credit loss impairments previously recognized due to increase in cash flows expected to be collected	0	0	0	0
Balance, end of period	$5,444	$7,488	$5,444	$7,488

Investments_Components_Of_Net_

Investments (Components Of Net Realized Gains, Excluding OTTI Charges) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'
HTM fixed income securities Gains	$0	$32,000	$3,000	$35,000
HTM fixed income securities Losses	-4,000	-37,000	-18,000	-86,000
Other investments Gains	1,000	0	1,000	0
Other Investments Losses	0	-80,000	0	-940,000
Total other net realized investment gains	15,231,000	14,111,000	28,370,000	25,124,000
Total OTTI charges recognized in earnings	0	-680,000	-1,382,000	-3,184,000
Total net realized gains	15,231,000	13,431,000	26,988,000	21,940,000
Proceeds From Sale Of Available For Sale Securities	89,900,000	67,200,000	221,500,000	116,300,000
Realized Gain On The Sale Of Private Equity [Member]	'	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'
Total net realized gains	'	'	'	4,700,000
Fixed Income Securities [Member]	'	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'
AFS securities Gains	695,000	662,000	1,633,000	2,580,000
AFS securities Losses	-29,000	-31,000	-172,000	-330,000
Equity Securities [Member]	'	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'
AFS securities Gains	14,576,000	13,801,000	27,255,000	24,272,000
AFS securities Losses	-8,000	-236,000	-332,000	-407,000
Proceeds Due To Rebalancing Of Equity Securities Portfolio [Member]	'	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'	'
Total net realized gains	'	$13,500,000	'	$19,100,000

Fair_Value_Measurements_Carryi

Fair Value Measurements (Carrying Value and Estimated Fair Value of Financial Instruments) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Held-to-maturity Securities	$336,082	$392,879
Available-for-sale Securities	3,967,638	3,715,536
Equity securities, AFS	211,266	192,771
Short-term investments	181,593	174,251
Notes payable	392,294	392,414
Carrying Amount [Member]	'	'
Held-to-maturity Securities	336,082	392,879
Available-for-sale Securities	3,967,638	3,715,536
Equity securities, AFS	211,266	192,771
Short-term investments	181,593	174,251
Notes payable	392,294	392,414
Carrying Amount [Member] | Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member]	'	'
Notes payable	13,000	13,000
Carrying Amount [Member] | One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member]	'	'
Notes payable	45,000	45,000
Carrying Amount [Member] | Seven Point Twenty Five Percent Senior Notes [Member]	'	'
Notes payable	49,896	49,916
Carrying Amount [Member] | Six Point Seventy Percent Senior Notes [Member]	'	'
Notes payable	99,398	99,498
Carrying Amount [Member] | Five Point Eight Hundred Seventy Five Senior Notes [Member]	'	'
Notes payable	185,000	185,000
Fair Value [Member]	'	'
Held-to-maturity Securities	354,190	416,981
Available-for-sale Securities	3,967,638	3,715,536
Equity securities, AFS	211,266	192,771
Short-term investments	181,593	174,251
Notes payable	405,183	354,010
Fair Value [Member] | Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member]	'	'
Notes payable	13,085	13,319
Fair Value [Member] | One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member]	'	'
Notes payable	45,220	45,259
Fair Value [Member] | Seven Point Twenty Five Percent Senior Notes [Member]	'	'
Notes payable	56,970	50,887
Fair Value [Member] | Six Point Seventy Percent Senior Notes [Member]	'	'
Notes payable	110,310	98,247
Fair Value [Member] | Five Point Eight Hundred Seventy Five Senior Notes [Member]	'	'
Notes payable	$179,598	$146,298

Fair_Value_Measurements_Quanti

Fair Value Measurements (Quantitative Disclosures of Fair Value Assets) (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Available-for-sale Securities, Debt Securities	$3,967,638		$3,715,536
Equity securities, AFS	211,266		192,771
Total AFS securities	4,178,904		3,908,307
Short-term investments	181,593		174,251
Fair Value [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	3,967,638		3,715,536
Equity securities, AFS	211,266		192,771
Total AFS securities	4,178,904		3,908,307
Short-term investments	181,593		174,251
Total assets measured at fair value	4,360,497		4,082,558
Fair Value [Member] | U.S. Government and Government Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	151,689		173,375
Fair Value [Member] | Foreign Government [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	27,867		30,615
Fair Value [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	1,229,234		951,624
Fair Value [Member] | Corporate Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	1,763,230		1,734,883
Fair Value [Member] | Asset-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	146,966		140,896
Fair Value [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	165,518		171,284
Fair Value [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	483,134		512,859
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	51,467	[1]	52,153	[1]
Equity securities, AFS	208,366	[1]	189,871	[1]
Total AFS securities	259,833	[1]	242,024	[1]
Short-term investments	181,593	[1]	174,251	[1]
Total assets measured at fair value	441,426	[1]	416,275	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | U.S. Government and Government Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	51,467	[1]	52,153	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Foreign Government [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0	[1]	0	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0	[1]	0	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Corporate Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0	[1]	0	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Asset-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0	[1]	0	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0	[1]	0	[1]
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0	[1]	0	[1]
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	3,916,171	[1]	3,663,383	[1]
Equity securities, AFS	0	[1]	0	[1]
Total AFS securities	3,916,171	[1]	3,663,383	[1]
Short-term investments	0	[1]	0	[1]
Total assets measured at fair value	3,916,171	[1]	3,663,383	[1]
Significant Other Observable Inputs (Level 2) [Member] | U.S. Government and Government Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	100,222	[1]	121,222	[1]
Significant Other Observable Inputs (Level 2) [Member] | Foreign Government [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	27,867	[1]	30,615	[1]
Significant Other Observable Inputs (Level 2) [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	1,229,234	[1]	951,624	[1]
Significant Other Observable Inputs (Level 2) [Member] | Corporate Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	1,763,230	[1]	1,734,883	[1]
Significant Other Observable Inputs (Level 2) [Member] | Asset-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	146,966	[1]	140,896	[1]
Significant Other Observable Inputs (Level 2) [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	165,518	[1]	171,284	[1]
Significant Other Observable Inputs (Level 2) [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	483,134	[1]	512,859	[1]
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Equity securities, AFS	2,900		2,900
Total AFS securities	2,900		2,900
Short-term investments	0		0
Total assets measured at fair value	2,900		2,900
Significant Unobservable Inputs (Level 3) [Member] | U.S. Government and Government Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Significant Unobservable Inputs (Level 3) [Member] | Foreign Government [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Significant Unobservable Inputs (Level 3) [Member] | Obligations of States and Political Subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Significant Unobservable Inputs (Level 3) [Member] | Corporate Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Significant Unobservable Inputs (Level 3) [Member] | Asset-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Significant Unobservable Inputs (Level 3) [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	0		0
Significant Unobservable Inputs (Level 3) [Member] | Residential Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]	'		'
Available-for-sale Securities, Debt Securities	$0		$0
[1]	1 There were no transfers of securities between Level 1 and Level 2.

Fair_Value_Measurements_Change

Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) (USD $)	12 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2013		Dec. 31, 2013		Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2013		Dec. 31, 2013		Dec. 31, 2013		Dec. 31, 2013		Dec. 31, 2013
			Equity Securities [Member]		Receivable For Proceeds From Divestiture Of Business [Member]		Fixed Income Securities [Member]	Fixed Income Securities [Member]	Fixed Income Securities [Member]		Fixed Income Securities [Member]		Fixed Income Securities [Member]		Fixed Income Securities [Member]		Fair Value, Inputs, Level 3 [Member]
									U.S. Government and Government Agencies [Member]		Corporate Securities [Member]		Asset-Backed Securities [Member]		Commercial Mortgage Backed Securities [Member]		AFS Fixed Income Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'		'		'		'	'	'		'		'		'		'
Fair value, Beginning balance	$42,277		$3,607		$2,705		$0	$0	$19,789		$2,946		$6,068		$7,162		'
Total net (losses) gains for the period included in OCI	4,089	[1]	3,935	[1]	0	[1]	'	'	-537	[1]	-7	[1]	-74	[1]	772	[1]	'
Total net (losses) gains for the period included in net income	-1,195	[2],[3]	0	[2],[3]	-1,480	[2],[3]	'	'	-76	[2],[3]	0	[2],[3]	0	[2],[3]	361	[2],[3]	'
Purchases	0		0		0		'	'	0		0		0		0		'
Sales	0		0		0		'	'	0		0		0		0		'
Issuances	0		0		0		'	'	0		0		0		0		'
Settlements	-4,660		0		-225		'	'	-1,847		-168		0		-2,420		'
Transfers into Level 3	0		0		0		'	'	0		0		0		0		'
Transfers out of Level 3	-37,611		-4,642		-1,000		'	'	-17,329		-2,771		-5,994		-5,875		-32,000
Fair value, Ending balance	$2,900		$2,900		$0		$0	$0	$0		$0		$0		$0		'
[1]	Amounts are reported in “Unrealized holding (losses) gains arising during period” on the Consolidated Statements of Comprehensive Income in our 2013 Annual Report.
[2]	For the receivable related to the sale of Selective HR, amounts in "Loss on disposal of discontinued operations, net of tax" relate to an impairment charge and amounts in "Other income" relate to interest accretion on the Consolidated Statements of Income in our 2013 Annual Report.
[3]	Amounts are reported in “Net realized gains” for realized gains and losses and “Net investment income earned” for amortization of securities on the Consolidated Statements of Income in our 2013 Annual Report.

Fair_Value_Measurements_Quanti1

Fair Value Measurements (Quantitative Information of Our Financial Assets and Liabilities That Were Disclosed at Fair Value) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	$336,082	$392,879
Notes payable	392,294	392,414
Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	354,190	416,981
Notes payable	405,183	354,010
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Notes payable	179,598	146,298
Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	354,190	416,981
Notes payable	225,585	207,712
Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Notes payable	0	0
Foreign Government [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	5,407	5,591
Foreign Government [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Foreign Government [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	5,407	5,591
Foreign Government [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Obligations of States and Political Subdivisions [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	317,609	369,756
Obligations of States and Political Subdivisions [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Obligations of States and Political Subdivisions [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	317,609	369,756
Obligations of States and Political Subdivisions [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Corporate Securities [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	22,726	30,274
Corporate Securities [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Corporate Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	22,726	30,274
Corporate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Asset-Backed Securities [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	3,124	3,415
Asset-Backed Securities [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Asset-Backed Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	3,124	3,415
Asset-Backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Commercial Mortgage Backed Securities [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	5,324	7,945
Commercial Mortgage Backed Securities [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Commercial Mortgage Backed Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	5,324	7,945
Commercial Mortgage Backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Held-to-maturity Securities	0	0
Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	13,085	13,319
Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	13,085	13,319
Two Point Ninety Percent Borrowing From Federal Home Loan Bank [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	45,220	45,259
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	45,220	45,259
One Point Twenty Five Percent Borrowing From Federal Home Loan Bank [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Seven Point Twenty Five Percent Senior Notes [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	56,970	50,887
Seven Point Twenty Five Percent Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Seven Point Twenty Five Percent Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	56,970	50,887
Seven Point Twenty Five Percent Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Six Point Seventy Percent Senior Notes [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	110,310	98,247
Six Point Seventy Percent Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Six Point Seventy Percent Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	110,310	98,247
Six Point Seventy Percent Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Five Point Eight Hundred Seventy Five Senior Notes [Member] | Fair Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	179,598	146,298
Five Point Eight Hundred Seventy Five Senior Notes [Member] | Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	179,598	146,298
Five Point Eight Hundred Seventy Five Senior Notes [Member] | Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	0	0
Five Point Eight Hundred Seventy Five Senior Notes [Member] | Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Notes payable	$0	$0

Reinsurance_List_of_Direct_Ass

Reinsurance (List of Direct, Assumed, and Ceded Reinsurance Amounts) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Effects of Reinsurance [Line Items]	'	'	'	'
Decrease in direct loss and loss expense incurred	$46,100,000	'	'	'
Premiums written:	'	'	'	'
Direct	592,858,000	570,849,000	1,723,063,000	1,650,855,000
Assumed	5,780,000	22,053,000	19,467,000	34,913,000
Ceded premiums written	-103,517,000	-100,154,000	-290,836,000	-280,719,000
Net	495,121,000	492,748,000	1,451,694,000	1,405,049,000
Premiums earned:	'	'	'	'
Direct	548,734,000	518,307,000	1,630,347,000	1,516,454,000
Assumed	6,789,000	11,066,000	27,359,000	32,480,000
Ceded premiums earned	-92,884,000	-91,805,000	-274,947,000	-264,174,000
Net	462,639,000	437,568,000	1,382,759,000	1,284,760,000
Loss and loss expense incurred:	'	'	'	'
Direct	304,525,000	350,648,000	995,581,000	1,055,248,000
Assumed	5,362,000	7,264,000	20,218,000	22,758,000
Ceded loss and loss expense incurred	-38,955,000	-74,595,000	-126,526,000	-245,246,000
Net	270,932,000	283,317,000	889,273,000	832,760,000
Percentage of NFIP claims ceded by federal government	'	'	100.00%	'
Hurricane Sandy [Member]	'	'	'	'
Effects of Reinsurance [Line Items]	'	'	'	'
Reduction in estimated ultimate exposure	4,000,000	'	'	'
Hurricane Sandy [Member] | Catastrophe excess of loss treaty [Member]	'	'	'	'
Effects of Reinsurance [Line Items]	'	'	'	'
Reduction in estimated ultimate exposure	$3,600,000	'	'	'

Reinsurance_Ceded_Premiums_and

Reinsurance (Ceded Premiums and Losses Related to Flood Operations) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Ceded premiums written	($103,517)	($100,154)	($290,836)	($280,719)
Ceded premiums earned	-92,884	-91,805	-274,947	-264,174
Ceded loss and loss expense incurred	-38,955	-74,595	-126,526	-245,246
National Flood Insurance Program [Member]	'	'	'	'
Ceded premiums written	-69,922	-64,196	-193,000	-183,364
Ceded premiums earned	-60,761	-57,920	-178,260	-169,697
Ceded loss and loss expense incurred	($14,008)	($34,879)	($48,099)	($162,780)

Segment_Information_Narrative_

Segment Information Narrative (Details) (USD $)	3 Months Ended	9 Months Ended
	Mar. 31, 2014	Sep. 30, 2014	Sep. 30, 2013
Number of Operating Segments	'	3	'
Gross premiums of self-insured pooled group renewal book of business sold	$38,000,000	'	'
Proceeds from sale of renewal rights	$8,000,000	$8,000,000	$0

Segment_Information_Revenue_Fr

Segment Information (Revenue From Continuing Operations by Segment) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	$462,639	$437,568	$1,382,759	$1,284,760
Other income	3,196	3,357	14,931	9,677
Net investment income earned	34,292	32,457	106,600	99,330
Net realized investment gains	15,231	13,431	26,988	21,940
Total investment revenues	49,523	45,888	133,588	121,270
Total revenues from continuing operations	515,358	486,813	1,531,278	1,415,707
Commercial Automobile [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	83,536	79,138	249,224	230,191
Workers Compensation [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	66,732	66,510	205,137	197,449
General Liability [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	110,894	100,925	331,303	298,394
Commercial Property [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	61,304	57,004	182,716	165,356
Business Owners' Policies [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	21,649	19,629	63,797	56,794
Bonds Segment [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	4,791	4,705	14,281	14,244
Other Commercial [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	3,237	3,051	9,633	9,036
Total Standard Commercial Lines [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	352,143	330,962	1,056,091	971,464
Personal Automobile [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	37,695	38,513	113,943	115,432
Homeowners [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	33,957	32,374	100,831	95,211
Other Personal [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	2,725	3,827	8,965	10,655
Total Standard Personal Lines [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	74,377	74,714	223,739	221,298
Total Standard Insurance Operations [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	426,520	405,676	1,279,830	1,192,762
Total Standard insurance Operations revenues	429,716	409,018	1,294,753	1,202,352
Miscellaneous Income [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Other income	3,196	3,342	14,923	9,590
Excess And Surplus Operations [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total net premiums earned	36,119	31,892	102,929	91,998
Operating Segments [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Total revenues from continuing operations	515,358	486,798	1,531,270	1,415,620
Other Income [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Other income	$0	$15	$8	$87

Segment_Information_Income_Fro

Segment Information (Income From Continuing Operations, Before Federal Income Tax) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting Information [Line Items]	'	'	'	'
Net investment income earned	$34,292	$32,457	$106,600	$99,330
Net realized investment gains	15,231	13,431	26,988	21,940
Total investment revenues	49,523	45,888	133,588	121,270
Tax on investment income	13,858	12,648	36,374	31,960
Total investment income after federal income tax	35,665	33,240	97,214	89,310
Total Standard Commercial Lines [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Underwriting gain (loss), before federal income tax	27,771	8,776	39,844	24,621
Total Standard Personal Lines [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Underwriting gain (loss), before federal income tax	8,037	1,362	95	4,360
Total Standard Insurance Operations [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Underwriting gain (loss), before federal income tax	35,808	10,138	39,939	28,981
GAAP combined ratio	91.60%	97.50%	96.90%	97.60%
Statutory combined ratio	90.50%	96.00%	96.30%	96.60%
Excess And Surplus Operations [Member]	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'
Underwriting gain (loss), before federal income tax	($1,371)	$13	($433)	($2,186)
GAAP combined ratio	103.80%	100.00%	100.40%	102.40%
Statutory combined ratio	102.90%	100.50%	100.30%	101.90%

Segment_Information_Reconcilia

Segment Information (Reconciliation of Segment Results to Income from Continuing Operations, before Federal Income Tax (Details)) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'	'	'	'
Investment income, before federal income tax	$49,523	$45,888	$133,588	$121,270
Total all segments	83,960	56,039	173,094	148,065
Interest expense	-5,558	-5,570	-16,544	-16,971
General corporate and other expenses	-3,076	-5,984	-16,619	-21,540
Income from continuing operations, before federal income tax	75,326	44,485	139,931	109,554
Total Standard Insurance Operations [Member]	'	'	'	'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'	'	'	'
Underwriting gain (loss), before federal income tax	35,808	10,138	39,939	28,981
Excess And Surplus Operations [Member]	'	'	'	'
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]	'	'	'	'
Underwriting gain (loss), before federal income tax	($1,371)	$13	($433)	($2,186)

Retirement_Plans_Components_of

Retirement Plans (Components of Net Periodic Benefit Cost and Other Amount Recognized in Other Comprehensive Income) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items]	'	'	'	'
Curtailment expense	'	'	$0	$16
Retirement Income Plan [Member]	'	'	'	'
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items]	'	'	'	'
Service cost	1,627	1,857	4,880	6,163
Interest cost	3,253	3,053	9,760	9,407
Expected return on plan assets	-3,919	-3,986	-11,756	-11,819
Amortization of unrecognized prior service cost	'	'	0	10
Amortization of unrecognized net actuarial loss	367	772	1,102	3,366
Curtailment expense	'	'	0	16
Total net periodic cost	1,328	1,696	3,986	7,143
Retirement Life Plan [Member]	'	'	'	'
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items]	'	'	'	'
Service cost	0	0	0	0
Interest cost	73	69	219	208
Expected return on plan assets	0	0	0	0
Amortization of unrecognized prior service cost	'	'	0	0
Amortization of unrecognized net actuarial loss	14	18	40	53
Curtailment expense	'	'	0	0
Total net periodic cost	$87	$87	$259	$261

Retirement_Plans_WeightedAvera

Retirement Plans (Weighted-Average Expense Assumptions) (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Retirement Income Plan [Member]	'	'
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items]	'	'
Discount rate	5.16%	4.66%
Expected return on plan assets	6.92%	7.40%
Rate of compensation increase	4.00%	4.00%
Contributions by Employer	$8	'
Retirement Life Plan [Member]	'	'
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items]	'	'
Discount rate	4.85%	4.42%
Expected return on plan assets	0.00%	0.00%
Rate of compensation increase	0.00%	0.00%
Scenario, Forecast [Member] | Retirement Income Plan [Member]	'	'
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items]	'	'
Estimated contribution from the employer	$10.40	'

Comprehensive_Income_Component

Comprehensive Income (Components of Comprehensive Income-Gross and Net of Tax) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net income, Gross	$75,326	$44,485	$139,931	$108,019
Unrealized holding gains during the period, Gross	-13,831	9,820	64,255	-77,810
Non-credit OTTI recognized in OCI, Gross	'	'	'	77
Amounts reclassified into net income: HTM securities, Gross	-373	-472	-1,050	-1,803
Amounts reclassified into net income: non-credit OTTI	1,200	1	1,669	14
Realized gains on AFS securities, Gross	-16,435	-13,516	-28,672	-24,780
Net unrealized (losses) gains, Gross	-29,439	-4,167	36,202	-104,302
Net actuarial gain, Gross	'	'	'	44,000
Amount reclassified into Net Income: Net actuarial loss, Gross	381	790	1,142	3,419
Amount reclassified into Net Income: Prior service cost, Gross	'	'	'	10
Amount reclassified into Net Income: Curtailment expense	'	'	'	16
Defined pension and other post-retirement benefit plans, gross	381	790	1,142	47,445
Other comprehensive (loss) income, Gross	-29,058	-3,377	37,344	-56,857
Comprehensive income (loss), Gross	46,268	41,108	177,275	51,162
Net income, Tax	22,164	11,832	39,454	26,936
Unrealized holding (losses) gains during the period, Tax	-4,843	3,437	22,488	-27,234
Non-credit OTTI recognized in OCI, Tax	'	'	'	27
HTM securities, Tax	-130	-165	-367	-631
Non-credit OTTI, Tax	420	0	584	5
Realized gains on AFS securities, Tax	-5,752	-4,731	-10,035	-8,673
Net unrealized gains (losses), Tax	-10,305	-1,459	12,670	-36,506
Net actuarial gain, Tax	'	'	'	15,400
Amount reclassified into Net Income: Net actuarial loss, Tax	134	277	400	1,197
Amount reclassified into Net Income: Prior service cost, Tax	'	'	'	4
Amount reclassified into Net Income: Curtailment expense, tax	'	'	'	5
Defined pension and other post-retirement benefit plans, tax	134	277	400	16,606
Other comprehensive income (loss), Tax	-10,171	-1,182	13,070	-19,900
Comprehensive income (loss), Tax	11,993	10,650	52,524	7,036
Net income	53,162	32,653	100,477	81,083
Unrealized holding gains (losses) arising during period	-8,988	6,383	41,767	-50,576
Non-credit OTTI recognized in OCI	0	0	0	50
HTM Securities	-243	-307	-683	-1,172
Amounts reclassified into Net Income: Non-credit other-than-temporary impairments	780	1	1,085	9
Realized gains on available for sale securities	-10,683	-8,785	-18,637	-16,107
Total unrealized (losses) gains on investment securities	-19,134	-2,708	23,532	-67,796
Net actuarial gain	0	0	0	28,600
Amount reclassified into Net Income: Net actuarial loss	247	513	742	2,222
Amount reclassified into Net Income: Prior service cost	0	0	0	6
Other Comprehensive Income Loss Amortization Pension And Other Post Retirement Benefit Plans Curtailment Expense Recognized In Net Periodic Benefit Cost Net of Tax	0	0	0	11
Total defined benefit pension and post-retirement plans	247	513	742	30,839
Other comprehensive (loss) income	-18,887	-2,195	24,274	-36,957
Comprehensive income	$34,275	$30,458	$124,751	$44,126

Comprehensive_Income_Component1

Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	$24,851	'
Amounts reclassified into Net Income: Non-credit other-than-temporary impairments	780	1	1,085	9
OCI before reclassifications, Defined Benefit Pension and Post Retirement Plans	0	0	0	28,600
Amounts reclassified from AOCI, HTM Related	-243	-307	-683	-1,172
Amounts reclassified from AOCI, All Other	-10,683	-8,785	-18,637	-16,107
Other comprehensive income (loss)	-18,887	-2,195	24,274	-36,957
Other Comprehensive Income, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	247	513	742	30,839
Ending Balance, September 30, 2014	49,125	'	49,125	'
Available-for-sale Securities [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	51,635	'
OCI before reclassifications	'	'	41,767	'
Other comprehensive income (loss)	'	'	23,130	'
Ending Balance, September 30, 2014	74,765	'	74,765	'
Investments [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	51,503	'
OCI before reclassifications	'	'	41,767	'
Amounts reclassified from AOCI	'	'	-18,235	'
Other comprehensive income (loss)	'	'	23,532	'
Ending Balance, September 30, 2014	75,035	'	75,035	'
Accumulated Other-than-Temporary Impairment [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	-1,599	'
OCI before reclassifications	'	'	0	'
Other comprehensive income (loss)	'	'	1,085	'
Ending Balance, September 30, 2014	-514	'	-514	'
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Held-to-maturity Securities [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	1,467	'
OCI before reclassifications	'	'	0	'
Other comprehensive income (loss)	'	'	-683	'
Ending Balance, September 30, 2014	784	'	784	'
Accumulated Defined Benefit Plans Adjustment [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	-26,652	'
Other Comprehensive Income, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	'	'	742	'
Ending Balance, September 30, 2014	-25,910	'	-25,910	'
Accumulated other comprehensive income [Member]	'	'	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'
Beginning Balance,December 31, 2013	'	'	24,851	'
OCI before reclassifications	'	'	41,767	'
Amounts reclassified from AOCI	'	'	-17,493	'
Other comprehensive income (loss)	'	'	24,274	-36,957
Ending Balance, September 30, 2014	$49,125	'	$49,125	'

Comprehensive_Income_Reclassif

Comprehensive Income (Reclassification out of AOCI) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Amounts reclassified into net income: non-credit OTTI	$1,200	$1	$1,669	$14
Non-credit OTTI, Tax	-420	0	-584	-5
Amounts reclassified into Net Income: Non-credit other-than-temporary impairments	780	1	1,085	9
Total HTM Related, Tax	130	165	367	631
Amounts reclassified from AOCI, HTM Related	-243	-307	-683	-1,172
Realized gains on AFS disposals and OTTI	-16,435	-13,516	-28,672	-24,780
Total realized gains on AFS disposals and OTTI	5,752	4,731	10,035	8,673
Amounts reclassified into net income: realized gains on available for sale securities	-10,683	-8,785	-18,637	-16,107
Amount reclassified into Net Income: Net actuarial loss, Gross	381	790	1,142	3,419
Defined pension and other post-retirement benefit plans, tax	-134	-277	-400	-16,606
Amount reclassified into Net Income: Prior service cost, Gross	'	'	'	10
Amount reclassified into Net Income: Curtailment expense	'	'	'	16
Defined pension and other post-retirement benefit plans, gross	381	790	1,142	47,445
Total defined benefit pension and post-retirement plans	247	513	742	30,839
Net Investment Income Earned [Member]	'	'	'	'
Amortization of net unrealized gains on HTM securities	-385	-453	-1,137	-1,633
Net Investment Income Earned [Member] | Amortization Of Non Credit OTTI Losses On HTM Securities [Member]	'	'	'	'
Amounts reclassified into net income: non-credit OTTI	0	1	0	14
Income From Continuing Operations Before Federal Income Tax [Member]	'	'	'	'
Amounts reclassified into net income: non-credit OTTI	1,200	1	1,669	14
Amortization of net unrealized gains on HTM securities	-373	-472	-1,050	-1,803
Realized gains on AFS disposals and OTTI	-16,435	-13,516	-28,672	-24,780
Amount reclassified into Net Income: Net actuarial loss, Gross	381	790	1,142	3,419
Amount reclassified into Net Income: Prior service cost, Gross	0	0	0	10
Amount reclassified into Net Income: Curtailment expense	0	0	0	16
Defined pension and other post-retirement benefit plans, gross	381	790	1,142	3,445
Total Federal Income Tax Expense [Member]	'	'	'	'
Non-credit OTTI, Tax	-420	0	-584	-5
Total HTM Related, Tax	130	165	367	631
Total realized gains on AFS disposals and OTTI	5,752	4,731	10,035	8,673
Defined pension and other post-retirement benefit plans, tax	-134	-277	-400	-1,206
Net Income Financial Statement Line Item [Member]	'	'	'	'
Amounts reclassified into Net Income: Non-credit other-than-temporary impairments	780	1	1,085	9
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	-9,899	-8,578	-17,493	-15,031
Amounts reclassified from AOCI, HTM Related	-243	-307	-683	-1,172
Amounts reclassified into net income: realized gains on available for sale securities	-10,683	-8,785	-18,637	-16,107
Total defined benefit pension and post-retirement plans	247	513	742	2,239
Net Realized Investment Gains [Member]	'	'	'	'
Unrealized gains and losses on HTM disposals	12	-19	87	-170
Realized gains on AFS disposals and OTTI	-16,435	-13,516	-28,672	-24,780
Net Realized Investment Gains [Member] | Non-credit OTTI on Disposed Securities [Member]	'	'	'	'
Amounts reclassified into net income: non-credit OTTI	1,200	0	1,669	0
Loss And Loss Expense Incurred [Member]	'	'	'	'
Amount reclassified into Net Income: Net actuarial loss, Gross	88	159	263	717
Amount reclassified into Net Income: Prior service cost, Gross	0	0	0	7
Policy acquisition costs [Member]	'	'	'	'
Amount reclassified into Net Income: Net actuarial loss, Gross	293	631	879	2,702
Amount reclassified into Net Income: Prior service cost, Gross	0	0	0	3
Amount reclassified into Net Income: Curtailment expense	$0	$0	$0	$16