Condensed Consolidated Statements of Earnings (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Revenues	$ 634.2us-gaap_Revenues	$ 606.3us-gaap_Revenues	$ 1,764.6us-gaap_Revenues	$ 1,672.1us-gaap_Revenues
Cost of revenues	452.6us-gaap_CostOfRevenue	427.6us-gaap_CostOfRevenue	1,273.1us-gaap_CostOfRevenue	1,210.2us-gaap_CostOfRevenue
Selling, general and administrative expenses	92.0	95.6	284.8	255.1
Other expenses, net	7.7us-gaap_OtherNonoperatingIncomeExpense	6.2us-gaap_OtherNonoperatingIncomeExpense	23.2us-gaap_OtherNonoperatingIncomeExpense	17.9us-gaap_OtherNonoperatingIncomeExpense
Total expenses	552.3us-gaap_CostsAndExpenses	529.4us-gaap_CostsAndExpenses	1,581.1us-gaap_CostsAndExpenses	1,483.2us-gaap_CostsAndExpenses
Earnings before income taxes	81.9	76.9	183.5	188.9
Provision for income taxes	27.9us-gaap_IncomeTaxExpenseBenefit	26.1us-gaap_IncomeTaxExpenseBenefit	62.3us-gaap_IncomeTaxExpenseBenefit	66.1us-gaap_IncomeTaxExpenseBenefit
Net earnings	$ 54.0us-gaap_ProfitLoss	$ 50.8us-gaap_ProfitLoss	$ 121.2us-gaap_ProfitLoss	$ 122.8us-gaap_ProfitLoss
Basic earnings per share (in dollars per share)	$ 0.45us-gaap_EarningsPerShareBasic	$ 0.42us-gaap_EarningsPerShareBasic	$ 1.01us-gaap_EarningsPerShareBasic	$ 1.03us-gaap_EarningsPerShareBasic
Diluted earnings per share (in dollars per share)	$ 0.43us-gaap_EarningsPerShareDiluted	$ 0.41us-gaap_EarningsPerShareDiluted	$ 0.97us-gaap_EarningsPerShareDiluted	$ 0.99us-gaap_EarningsPerShareDiluted
Weighted-average shares outstanding:
Basic (in shares)	120.6	119.7	120.2	119.3
Diluted (in shares)	125.0	124.8	124.4	124.0
Dividends declared per common share (in dollars per share)	$ 0.27	$ 0.21	$ 0.81	$ 0.63

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Aggregate dividends declared during the period for each share of common stock outstanding.

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