Debt - Schedule of Long-term Debt Outstanding (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018
Revolving Credit Agreement
Total	$ 550,600,000	$ 545,700,000
Less: amounts due within one year	0	0
Long-term debt, net of current portion	$ 550,600,000	545,700,000
Senior unsecured notes, 5.20% due July 2021 (face value of $250.0 million at June 30, 2019 and 2018)
Revolving Credit Agreement
Interest rate	5.20%
Face amount	$ 250,000,000.0	250,000,000.0
Total	$ 251,200,000	246,600,000
Senior unsecured notes, 4.45% due March 2023 (face value of $300.0 million at June 30, 2019 and 2018)
Revolving Credit Agreement
Interest rate	4.45%
Face amount	$ 300,000,000.0	300,000,000.0
Total	$ 299,400,000	$ 299,100,000

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

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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