INVESTMENTS-AFFILIATED COMPANIES (Tables)

12 Months Ended

Dec. 31, 2017

Equity Method Investments and Joint Ventures [Abstract]

Investment in non-consolidated equity affiliates

The following table summarizes our investment in our non-consolidated equity affiliate:

	December 31,
	2017		2016
	($ in millions)
Bay Gas	$	28.5	$	26.7

Summary of equity earnings of non-consolidated affiliates

The following table summarizes our equity earnings of our non-consolidated affiliate:

	Years Ended December 31,
	2017		2016		2015
	($ in millions)
Bay Gas	$	1.8	$	1.7	$	1.7