Equity Method Investments and Related-Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017
Schedule of Equity Method Investments [Line Items]
Foreign currency translation adjustments, net of tax		$ 203	$ 3,525
Income (loss) from equity method investments		1,065	(513)
Euro Infrastructure Co [Member]
Schedule of Equity Method Investments [Line Items]
Payments, net of transaction costs, to acquire the issued shares in investment	$ 139,500
Equity method investment ownership percentage	49.00%
Foreign currency translation adjustments, net of tax		$ 3,500	2,000
Maximum useful life of intangible assets basis difference, years		11 years
Weighted average useful life of intangible assets basis difference, years		10 years
Maximum useful life of tangible assets basis difference, years		11 years
Weighted average useful life of tangible assets basis difference, years		11 years
Income (loss) from equity method investments		$ 1,100	$ (500)
Retained earnings of undistributed cumulative earnings in equity interests, net of tax		$ 2,800

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of consolidated retained earnings that represent undistributed (not yet received) earnings from 50% or less owned persons accounted for by the equity method (equity method investees).

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The maximum useful life of the basis difference assigned to finite-lived intangible assets in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

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The weighted average amortization period of the basis difference assigned to finite-lived intangible assets, in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

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The net of transaction cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The maximum useful life of the portion of the basis difference assigned to tangible assets, in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

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The weighted average amortization period of the basis difference assigned to tangible assets, in 'PnYnMdDTnHnMnS' format (the basis difference defined as the difference between the amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee).

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