Borrowings - Outstanding Borrowings (Details) - USD ($)	Jun. 30, 2017	Jun. 30, 2016
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	$ 1,110,000,000
Current portion of long-term debt	0	$ 124,800,000
Long-term debt, excluding current portion	1,102,100,000	890,700,000
Total	1,102,100,000	1,015,500,000
Unused Available Capacity	790,000,000
Fair Value at June 30, 2017	1,123,700,000
Long-term debt, excluding current portion
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	1,110,000,000
Long-term debt, excluding current portion	1,102,100,000	890,700,000
Unused Available Capacity	790,000,000
Current portion of long-term debt
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	0
Current portion of long-term debt	0	124,800,000
Fair Value at June 30, 2017	0
Accounting Standards Update 2015-03 \| Other noncurrent assets
Line Of Credit Facility Covenant Compliance [Line Items]
Debt issuance costs		(7,100,000)
Accounting Standards Update 2015-03 \| Long-term debt, excluding current portion
Line Of Credit Facility Covenant Compliance [Line Items]
Debt issuance costs		7,000,000
Accounting Standards Update 2015-03 \| Current portion of long-term debt
Line Of Credit Facility Covenant Compliance [Line Items]
Debt issuance costs		100,000
Senior Notes \| Fiscal 2007 Senior Notes
Line Of Credit Facility Covenant Compliance [Line Items]
Debt issuance costs		100,000
Senior Notes \| Fiscal 2007 Senior Notes \| Current portion of long-term debt
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	0
Current portion of long-term debt	0	124,800,000
Senior Notes \| Fiscal 2014 Senior Notes
Line Of Credit Facility Covenant Compliance [Line Items]
Debt issuance costs	1,900,000	2,500,000
Senior Notes \| Fiscal 2014 Senior Notes \| Long-term debt, excluding current portion
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	400,000,000
Long-term debt, excluding current portion	397,900,000	397,200,000
Senior Notes \| Fiscal 2016 Senior Notes
Line Of Credit Facility Covenant Compliance [Line Items]
Debt issuance costs	4,000,000	4,500,000
Senior Notes \| Fiscal 2016 Senior Notes \| Long-term debt, excluding current portion
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	500,000,000
Long-term debt, excluding current portion	494,100,000	493,500,000
Revolving Credit Facility \| Fiscal 2017 Revolving Credit Facility \| Long-term debt, excluding current portion
Line Of Credit Facility Covenant Compliance [Line Items]
Par value at June 30, 2017	210,000,000
Long-term debt, excluding current portion	210,000,000	0
Unused Available Capacity	790,000,000
Fair Value at June 30, 2017	210,000,000
Level 1 \| Senior Notes \| Fiscal 2007 Senior Notes
Line Of Credit Facility Covenant Compliance [Line Items]
Fair Value at June 30, 2017	0	129,100,000
Level 1 \| Senior Notes \| Fiscal 2014 Senior Notes
Line Of Credit Facility Covenant Compliance [Line Items]
Fair Value at June 30, 2017	419,100,000	427,600,000
Level 1 \| Senior Notes \| Fiscal 2016 Senior Notes
Line Of Credit Facility Covenant Compliance [Line Items]
Fair Value at June 30, 2017	$ 494,600,000	$ 507,900,000

Line Of Credit Facility Covenant Compliance [Line Items]

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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