Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 26.6	$ 16.0
Unrealized gain (loss) on available-for-sale securities, net of tax	0.1	(0.2)
Change in foreign currency translation adjustment, net of tax	(0.2)	(0.7)
Comprehensive income	$ 26.5	$ 15.1

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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