EMPLOYEE BENEFITS (Tables)

6 Months Ended

Jun. 30, 2018

Retirement Benefits [Abstract]

Schedule of net benefit costs

The following tables show the components of net periodic pension and OPEB costs for our benefit plans.

	Pension Costs
	Three Months Ended June 30						Six Months Ended June 30
(in millions)	2018			2017			2018			2017
Service cost	$	11.8		$	10.4		$	23.8		$	22.1
Interest cost	28.7			30.2			57.0			61.4
Expected return on plan assets	(48.8		)	(48.5		)	(98.4		)	(98.1		)
Loss on plan settlement	0.3			5.3			0.7			5.3
Amortization of prior service cost	0.6			0.8			1.3			1.5
Amortization of net actuarial loss	23.9			21.1			47.0			43.0
Net periodic benefit cost	$	16.5		$	19.3		$	31.4		$	35.2

	OPEB Costs
	Three Months Ended June 30						Six Months Ended June 30
(in millions)	2018			2017			2018			2017
Service cost	$	5.6		$	5.6		$	11.8		$	11.9
Interest cost	7.4			8.4			14.9			16.9
Expected return on plan assets	(14.8		)	(13.6		)	(29.7		)	(27.3		)
Amortization of prior service credit	(3.9		)	(2.8		)	(7.7		)	(5.6		)
Amortization of net actuarial loss	0.2			0.1			0.5			1.6
Net periodic benefit credit	$	(5.5	)	$	(2.3	)	$	(10.2	)	$	(2.5	)

Schedule of non-service components

The following table shows the non-service credit components of net benefit costs:

	Three Months Ended June 30					Six Months Ended June 30
(in millions)	2018			2017		2018			2017
Non-service credit components	$	(5.3	)	$	—	$	(12.5	)	$	(2.6	)