Retirement Plans (Table)

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Schedule of Components of Net Periodic Benefit Cost

	Pension Plan			Pension Plan
	Quarter ended September 30,			Nine Months ended September 30,
($ in thousands)	2020		2019	2020	2019
Net Periodic Pension Cost (Benefit):
Interest cost	$	2,828	3,376	8,484	10,129
Expected return on plan assets	(5,477)		(5,278)	(16,430)	(15,835)
Amortization of unrecognized net actuarial loss	704		644	2,112	1,931
Total net periodic pension cost (benefit)1	$	(1,945)	(1,258)	(5,834)	(3,775)

1 The components of net periodic pension cost (benefit) are included within "Loss and loss expense incurred" and "Other insurance expenses" on the Consolidated Statements of Income.

Schedule of Weighted-Average Expense Assumptions

	Pension Plan
	Nine Months ended September 30,
	2020		2019
Weighted-Average Expense Assumptions:
Discount rate	3.33	%	4.46	%
Effective interest rate for calculation of interest cost	2.95		4.12
Expected return on plan assets	5.80		6.50