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Preferred and Common Stockholder's Equity - Schedule of Stock Repurchases (Detail) - USD ($) shares in Millions, $ in Millions | 12 Months Ended
--- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2015
Stockholders Equity [Line Items] |  |  |
Shares purchased and retired | 1.6 | 4.5 | 6.0
Common stock and additional paid-in-capital reductions | $ 14.6 | $ 41.2 | $ 51.5
Charges to retained earnings | $ 17.0 | $ 121.4 | $ 159.2
Common Stock [Member] |  |  |
Stockholders Equity [Line Items] |  |  |
Shares purchased and retired | 1.6 | 4.5 | 6.0

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- Definition Number of shares that have been repurchased and retired during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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