Remaining Annual Principal Payments of Credit Obligations (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Line Of Credit Facility [Line Items]
Year 1	$ 20,000
Year 2	26,555
Year 3	140,000
Year 4	345,000
Total	531,555
Term Loans
Line Of Credit Facility [Line Items]
Year 1	20,000
Year 2	20,000
Year 3	15,000
Total	55,000	$ 65,000
Yen Line of Credit
Line Of Credit Facility [Line Items]
Year 2	2,721
Total	2,721	2,714
U.S. Dollar Line of Credit
Line Of Credit Facility [Line Items]
Year 3	125,000
Total	125,000	$ 80,000
Note Payable
Line Of Credit Facility [Line Items]
Year 2	3,834
Total	3,834
Convertible Notes
Line Of Credit Facility [Line Items]
Year 4	345,000
Total	$ 345,000

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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