EMPLOYEE RETIREMENT PLANS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Pension plans [Member] | Emc Insurance Companies [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 3,216	$ 3,302	$ 9,647	$ 9,909
Interest cost	2,416	1,914	7,248	5,742
Expected return on plan assets	(5,183)	(4,288)	(15,549)	(12,863)
Amortization of net actuarial loss	91	1,491	274	4,472
Amortization of prior service cost (credit)	8	13	24	38
Net periodic benefit cost (income)	548	2,432	1,644	7,298
Pension plans [Member] | EMC Insurance Group, Inc. [Member]
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost (income)	170	753	510	2,260
Entity's share of estimated contributions to employee benefit plan			4,500
Postretirement benefit plans [Member] | Emc Insurance Companies [Member]
Components of net periodic benefit cost [Abstract]
Service cost	315	1,575	945	4,725
Interest cost	564	1,543	1,691	4,629
Expected return on plan assets	(1,099)	(908)	(3,297)	(2,723)
Amortization of net actuarial loss	413	923	1,238	2,770
Amortization of prior service cost (credit)	(2,867)	(622)	(8,600)	(1,868)
Net periodic benefit cost (income)	(2,674)	2,511	(8,023)	7,533
Amortization period for prior service credit from plan amendment			10 years
Postretirement benefit plans [Member] | EMC Insurance Group, Inc. [Member]
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost (income)	(770)	728	(2,312)	2,184
Entity's share of estimated contributions to employee benefit plan			$ 0