Equity Method Investments and Related Party Transactions - Additional Information (Detail) - Euro Infrastructure Co [Member]	12 Months Ended
Mar. 31, 2017	Mar. 03, 2017
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	49.00%	49.00%
Estimated useful life, years	11 years
Estimated weighted average life (In years)	10 years
Tangible assets, useful life	11 years
Tangible assets, weighted average useful life	11 years

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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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- Definition

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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- Definition

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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- Definition

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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