Long-term Debt - Schedule of Long-term Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018
Debt Instrument [Line Items]
Principal amount of long-term debt	$ 1,106,664	$ 1,073,394
Less unamortized discounts and debt issuance costs	(10,475)	(11,054)
Total long-term debt	1,096,189	1,062,340
Less current portion	(46,920)	(46,920)
Long-term debt, net of current portion	1,049,269	1,015,420
Bank credit facility - term loans
Debt Instrument [Line Items]
Principal amount of long-term debt	926,664	938,394
Bank credit facility - revolver loans
Debt Instrument [Line Items]
Principal amount of long-term debt	$ 180,000	$ 135,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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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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