EMPLOYEE RETIREMENT PLANS (Tables)

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

Components of net periodic benefit cost

The components of net periodic benefit cost (income) for Employers Mutual’s pension and postretirement benefit plans is as follows:

	Three months ended   March 31,
($ in thousands)	2018			2017
Pension plans:
Service cost	$	4,126		$	3,860
Interest cost	2,665			2,795
Expected return on plan assets	(5,978		)	(5,191		)
Amortization of net actuarial loss	125			908
Amortization of prior service cost	—			5
Net periodic pension benefit cost	$	938		$	2,377
Postretirement benefit plans:
Service cost	$	368		$	341
Interest cost	521			570
Expected return on plan assets	(1,204		)	(1,078		)
Amortization of net actuarial loss	234			343
Amortization of prior service credit	(2,782		)	(2,789		)
Net periodic postretirement benefit income	$	(2,863	)	$	(2,613	)