Goodwill and Other Intangibles (Tables)

3 Months Ended

Aug. 31, 2015

Goodwill and Intangible Assets Disclosure [Abstract]

Summary of Activity in Goodwill for the Periods Indicated

The following table summarizes the activity in Goodwill for the periods indicated: 

	Three months ended   August 31, 2015			Twelve months ended May 31, 2015			Three months ended   August 31, 2014
Gross beginning balance	$	155.9		$	156.0		$	156.0
Accumulated impairment	(39.6		)	(34.2		)	(34.2		)
Beginning balance	$	116.3		$	121.8		$	121.8
Impairment charge	—			(5.4		)	—
Foreign currency translation	(0.1		)	(0.1		)	0.0
Gross ending balance	$	155.8		$	155.9		$	156.0
Accumulated impairment	(39.6		)	(39.6		)	(34.2		)
Ending balance	$	116.2		$	116.3		$	121.8

Summary of Activity in Total Other Intangibles for the Periods Indicated

The following table summarizes the activity in Total other intangibles for the periods indicated:

	Three months ended   August 31, 2015			Twelve months ended May 31, 2015			Three months ended   August 31, 2014
Beginning balance - Other intangibles subject to amortization	$	4.7		$	5.8		$	5.8
Additions	0.5			0.8			0.6
Amortization expense	(0.5		)	(1.9		)	(0.5		)
Total other intangibles subject to amortization,   net of accumulated amortization of $17.8, $17.3     and $15.8, respectively	$	4.7		$	4.7		$	5.9
Total other intangibles not subject to   amortization	$	2.1		$	2.1		$	2.1
Total other intangibles	$	6.8		$	6.8		$	8.0