Accumulated Other Comprehensive (Loss)/Income (Tables)

6 Months Ended

Nov. 30, 2016

Accumulated Other Comprehensive (Loss)/Income [Abstract]

Changes in Accumulated Other Comprehensive (Loss)/Income

	For the three months ended,				For the six months ended
	November 30,				November 30,
In millions	2016		2015		2016		2015
Beginning balance	$	39.2	$	13.8	$	29.2	$	7.5
Other comprehensive (loss)/income:
Unrealized (losses)/gains on available-for-sale securities, net of tax		(56.0)		6.5		(46.0)		12.8
Total other comprehensive (loss)/ income, net of tax		(56.0)		6.5		(46.0)		12.8
Ending balance	$	(16.8)	$	20.3	$	(16.8)	$	20.3
Total tax (benefit)/expense included in other comprehensive income	$	(32.0)	$	3.8	$	(26.3)	$	7.4