Investment in Affiliates - Additional Information (Detail) - Fund II - European Joint Venture € in Millions	6 Months Ended
Jun. 30, 2016 EUR (€)
Investments In And Advances To Affiliates [Line Items]
Remaining commitment amount	€ 149
Capital commitment extension period	one year

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.

No definition available.

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