Non-controlling Interests - Additional Information (Detail) - Operating Partnership [Member] - ESL [Member]	Dec. 31, 2017
Noncontrolling Interest [Line Items]
Percentage of operating partnership interest held by parent	63.80%
Ownership interest percentage held by related party	36.20%

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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