Retirement Plans (Tables)

12 Months Ended

Dec. 31, 2017

Defined Benefit Plan Disclosure [Line Items]

Schedule Of Plan Terms In Effect And Revisions Of Retirement Savings Plan

(a) Selective Insurance Retirement Savings Plan (“Retirement Savings Plan”)

SICA offers a voluntary defined contribution 401(k) plan, which is available to most of our employees and is a tax-qualified retirement plan subject to the Employee Retirement Income Security Act of 1974 ("ERISA"). Expense recorded for this plan was $15.8 million in 2017, $15.0 million in 2016, and $14.1 million in 2015.

Schedule of Funded Status Of Retirement Income Plan And Retirement Life Plan



December 31,	Pension Plan
($ in thousands)	2017			2016
Change in Benefit Obligation:
Benefit obligation, beginning of year	$	330,588		310,308
Service cost	—			1,647
Interest cost	12,490			12,336
Actuarial losses	31,158			15,086
Benefits paid	(9,825		)	(8,789	)
Benefit obligation, end of year	$	364,411		330,588

Change in Fair Value of Assets:
Fair value of assets, beginning of year	$	316,515		249,700
Actual return on plan assets, net of expenses	46,983			21,079
Contributions by the employer to funded plans	10,000			54,525
Benefits paid	(9,825		)	(8,789	)
Fair value of assets, end of year	$	363,673		316,515

Funded status	$	(738	)	(14,073	)

Schedule of Amounts Recognized in Consolidated Balance Sheet



Amounts Recognized in the Consolidated Balance Sheet:
Liabilities	$	(738	)	(14,073	)
Net pension liability, end of year	$	(738	)	(14,073	)

Schedule of Amounts recognized in Accumulated Other than Comprehensive Income



Amounts Recognized in AOCI:
Net actuarial loss	$	87,438	85,845
Total	$	87,438	85,845

Schedule of Other Information as of December 31



Other Information as of December 31:
Accumulated benefit obligation	$	364,411	330,588

Schedule of Components Of Net Periodic Benefit Cost And Other Amounts Recognized In Other Comprehensive Income



	Pension Plan
($ in thousands)	2017			2016		2015
Components of Net Periodic Benefit Cost and Other Amounts Recognized in Other Comprehensive Income:

Net Periodic Benefit Cost:
Service cost	$	—		1,647		7,215
Interest cost	12,490			12,336		13,668
Expected return on plan assets	(19,419		)	(17,309	)	(15,969	)
Amortization of unrecognized actuarial loss	2,001			6,299		6,831
Total net periodic cost	$	(4,928	)	2,973		11,745

Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income:
Net actuarial loss (gain)	$	3,594		11,316		(1,425	)
Reversal of amortization of net actuarial loss	(2,001		)	(6,299	)	(6,831	)
Total recognized in other comprehensive income	$	1,593		5,017		(8,256	)

Total recognized in net periodic benefit cost and other comprehensive income	$	(3,335	)	7,990		3,489

Schedule Of Weighted- Average Expense and Liability Assumptions



	Pension Plan
	2017		2016	2015
Weighted-Average Expense Assumptions for the years ended December 31:
Discount rate	4.41	%	4.69	4.29
Expected return on plan assets	6.24		6.37	6.27
Rate of compensation increase¹	—		—	4.00



Weighted-Average Liability Assumptions as of December 31:
Discount rate	3.78	%	4.41

Schedule of Allocation of Plan Assets



	2017				2016
	Target Percentage²		Actual Percentage		Actual Percentage
Return seeking assets¹	20% - 60%		58	%	50	%
Liability hedging assets	40% - 80%		42	%	50	%
Total	100	%	100	%	100	%

Schedule of Quantitative Disclosures of our Financial Assets that were Measured at Fair Value



December 31, 2017			Fair Value Measurements Using
($ in thousands)	Assets Measured at Fair Value		Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1)¹	Significant Other Observable Inputs (Level 2)¹	Significant Unobservable Inputs (Level 3)
Description
Measured on a recurring basis:
AFS fixed income securities:
U.S. government and government agencies	$	49,740	24,652	25,088	—
Foreign government	18,555		—	18,555	—
Obligations of states and political subdivisions	1,582,970		—	1,582,970	—
Corporate securities	1,617,468		—	1,617,468	—
CLO and other ABS	795,458		—	795,458	—
CMBS	383,449		—	376,895	6,554
RMBS	714,882		—	714,882	—
Total AFS fixed income securities	5,162,522		24,652	5,131,316	6,554
AFS equity securities:
Common stock²	167,757		138,640	—	5,398
Preferred stock	14,948		14,948	—	—
Total AFS equity securities	182,705		153,588	—	5,398
Total AFS securities	5,345,227		178,240	5,131,316	11,952
Short-term investments	165,555		165,555	—	—
Total assets measured at fair value	$	5,510,782	343,795	5,131,316	11,952



December 31, 2016			Fair Value Measurements Using
($ in thousands)	Assets Measured at Fair Value		Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1)¹	Significant Other Observable Inputs (Level 2)¹	Significant Unobservable Inputs (Level 3)
Description
Measured on a recurring basis:
AFS fixed income securities:
U.S. government and government agencies	$	77,333	27,520	49,813	—
Foreign government	26,865		—	26,865	—
Obligations of states and political subdivisions	1,379,593		—	1,379,593	—
Corporate securities	1,997,753		—	1,997,753	—
CLO and other ABS	528,960		—	528,960	—
CMBS	256,842		—	256,842	—
RMBS	525,194		—	525,194	—
Total AFS fixed income securities	4,792,540		27,520	4,765,020	—
AFS equity securities:
Common stock	130,608		122,932	—	7,676
Preferred stock	16,145		16,145	—	—
Total AFS equity securities	146,753		139,077	—	7,676
Total AFS securities	4,939,293		166,597	4,765,020	7,676
Short-term investments	221,701		221,701	—	—
Total assets measured at fair value	$	5,160,994	388,298	4,765,020	7,676

¹There were no transfers of securities between Level 1 and Level 2.

² In accordance with ASU 2015-07, investments amounting to $23.7 million at December 31, 2017, respectively, were measured at fair value using the net asset value per share (or its practical expedient) and have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to total assets measured at fair value.

Schedule of Expected Benefit Payments

Payments



($ in thousands)	Pension Plan
Benefits Expected to be Paid in Future
Fiscal Years:
2018	$	12,913
2019	12,936
2020	13,987
2021	15,093
2022	16,128
2023-2027	94,542

Retirement Income Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Quantitative Disclosures of our Financial Assets that were Measured at Fair Value



December 31, 2017			Fair Value Measurements at 12/31/17 Using
($ in thousands)	Assets Measured at Fair Value At 12/31/17		Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Description
Return seeking assets:
Long-duration fixed income:
Global asset allocation fund	$	41,309	41,309		—		—
Global equity:
Non-U.S. equity	67,989		67,989		—		—
U.S. equity	66,353		66,353		—		—
Total global equity	134,342		134,342		—		—
Private assets:
Limited partnerships (at net asset value)¹:
Real assets	16,305		—		—		—
Private equity	1,096		—		—		—
Private credit	460		—		—		—
Hedge fund	15,192		—		—		—
Total limited partnerships	33,053		—		—		—
Other private assets	980		—		—		980
Total private assets	34,033		—		—		980
Total return seeking assets	209,684		175,651		—		980

Liability hedging assets:
Long-duration fixed income:
Extended duration fixed income	146,837		146,837		—		—
Cash and short-term investments:
Short-term investments	4,939		4,939		—		—
Deposit administration contracts	1,615		—		1,615		—
Total cash and short-term investments	6,554		4,939		1,615		—
Total liability hedging assets	153,391		151,776		1,615		—
Total invested assets	$	363,075	$	327,427	$	1,615	$	980



December 31, 2016			Fair Value Measurements at 12/31/16 Using
($ in thousands)	Assets Measured at Fair Value At 12/31/16		Quoted Prices in Active Markets for Identical Assets/ Liabilities (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Description
Return seeking assets:
Long-duration fixed income:
Global asset allocation fund	$	37,878	37,878		—		—
Global equity:
Non-U.S. equity	48,836		48,836		—		—
U.S. equity	55,073		55,073		—		—
Total global equity	103,909		103,909		—		—
Private assets (limited partnerships, at net asset value)¹:
Real assets	15,466		—		—		—
Private equity	1,615		—		—		—
Private credit	1,108		—		—		—
Total private assets	18,189		—		—		—
Total return seeking assets	159,976		141,787		—		—

Liability hedging assets:
Long-duration fixed income:
Extended duration fixed income	131,457		131,457		—		—
Cash and short-term investments:
Short-term investments	23,722		23,722		—		—
Deposit administration contracts	1,832		—		1,832		—
Total cash and short-term investments	25,554		23,722		1,832		—
Total liability hedging assets	157,011		155,179		1,832		—
Total invested assets	$	316,987	$	296,966	$	1,832	$	—

¹In accordance with ASU 2015-07, certain investments that are measured at fair value using the net asset value per share (or its practical expedient) have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to total Pension Plan invested assets.