EMPLOYEE RETIREMENT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Pension plans [Member] | Emc Insurance Companies [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 3,330	$ 3,240	$ 6,974	$ 6,431
Interest cost	2,364	2,451	4,642	4,832
Expected return on plan assets	(5,074)	(5,183)	(10,149)	(10,366)
Amortization of net actuarial loss	797	119	1,314	183
Amortization of prior service cost (credit)	7	8	15	16
Net periodic benefit cost (income)	1,424	635	2,796	1,096
Pension plans [Member] | EMC Insurance Group, Inc. [Member]
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost (income)	436	196	857	340
Entity's share of estimated contributions to employee benefit plan			2,100
Postretirement benefit plans [Member] | Emc Insurance Companies [Member]
Components of net periodic benefit cost [Abstract]
Service cost	353	315	706	630
Interest cost	537	563	1,074	1,127
Expected return on plan assets	(1,104)	(1,099)	(2,208)	(2,198)
Amortization of net actuarial loss	436	412	872	825
Amortization of prior service cost (credit)	(2,867)	(2,866)	(5,733)	(5,733)
Net periodic benefit cost (income)	(2,645)	(2,675)	(5,289)	(5,349)
Postretirement benefit plans [Member] | EMC Insurance Group, Inc. [Member]
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost (income)	$ (762)	$ (771)	(1,500)	$ (1,500)
Entity's share of estimated contributions to employee benefit plan			$ 0