This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
-Paragraph 25
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Schedule of Equity in Nonconsolidated Investment (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Nov. 30, 2017
Schedule Of Equity Method Investments [Line Items]
Equity Investment, Ownership Percentage	93.80%		93.80%
Equity Investment	$ 75,289	$ 69,215
Equity Investment
Schedule Of Equity Method Investments [Line Items]
Equity Investment	$ 57,400	$ 56,300
Nonconsolidated Investment \| Equity Investment \| USA
Schedule Of Equity Method Investments [Line Items]
Equity Investment, Ownership Percentage	93.80%
Equity Investment	$ 57,436