INCOME TAXES - Unrecognized Tax Benefit Reconciliation (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
Unrecognized tax benefits [Roll Forward]
Unrecognized tax benefits, beginning of year	$ 0.3	$ 0.3	$ 0.1
Additions based on tax positions related to the current year			0.1
Additions for tax positions of prior years			0.2
Reductions for tax positions of prior years (lapse of statute of limitations)	(0.3)	0	(0.1)
Unrecognized tax benefits, end of year	$ 0	$ 0.3	$ 0.3