Stock Based Compensation - Assumptions Used To Estimate Fair Value For Stock Options Granted (Details) (USD $)
9 Months Ended 6 Months Ended
Mar. 31, 2015
Mar. 31, 2015
Incentive Equity Awards Converted From ADP Awards    
Assumptions used    
Risk-free interest rate 1.10%  
Dividend yield 1.10%  
Weighted average volatility factor 23.90%  
Weighted average expected life (in years) 3 years 4 months 24 days  
Weighted average fair value (in dollars) $ 12.50  
Employee Stock Option    
Assumptions used    
Risk-free interest rate   1.60%
Dividend yield   1.10%
Weighted average volatility factor   25.60%
Weighted average expected life (in years)   6 years 3 months 18 days
Weighted average fair value (in dollars)   $ 10.24