Retirement Plans (Table)

6 Months Ended

Jun. 30, 2019

Retirement Benefits [Abstract]

Schedule of Components of Net Periodic Benefit Cost

	Pension Plan					Pension Plan
	Quarter ended June 30,					Six Months ended June 30,
($ in thousands)	2019			2018		2019		2018
Net Periodic Pension Cost (Benefit):
Interest cost	$	3,376		3,095		6,753		6,190
Expected return on plan assets	(5,278		)	(5,681	)	(10,557	)	(11,363	)
Amortization of unrecognized net actuarial loss	643			493		1,287		987
Total net periodic pension cost (benefit)1	$	(1,259	)	(2,093	)	(2,517	)	(4,186	)

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
	Six Months ended June 30,
	2019		2018
Weighted-Average Expense Assumptions:
Discount rate	4.46	%	3.78	%
Effective interest rate for calculation of interest cost	4.12		3.46
Expected return on plan assets	6.50		6.36