Other Noncontrolling Interests - Additional Information (Detail) - Other [Member]	Jun. 30, 2017 joint_venture
Noncontrolling Interest [Line Items]
Number of consolidated joint ventures	2
Maximum [Member]
Noncontrolling Interest [Line Items]
Voting interests of third-party owners	27.00%

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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