Employee Benefit Plans Employee Benefit Plans (Investments of the Plan Measured at Fair Value) (Details) - USD ($) $ in Millions	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 2,009.8	$ 2,024.1	$ 1,676.1
Comingled Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	1,082.7	1,261.1
Comingled Trusts [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Comingled Trusts [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	1,082.7	1,261.1
Comingled Trusts [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	270.7	271.9
US Treasury and Government [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
US Treasury and Government [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	270.7	271.9
US Treasury and Government [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	89.0	88.2
Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	89.0	88.2
Mutual Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Mutual Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Corporate And Municipal Bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	347.5	368.3
Corporate And Municipal Bonds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Corporate And Municipal Bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	347.5	368.3
Corporate And Municipal Bonds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	34.5	22.9
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	34.5	22.9
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Total Pension Assets Excluding Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	1,824.4	2,012.4
Total Pension Assets Excluding Cash [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	89.0	88.2
Total Pension Assets Excluding Cash [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	1,735.4	1,924.2
Total Pension Assets Excluding Cash [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 0.0	$ 0.0