Organization - Summary of Reconciliation of Noncontrolling Interests (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Redeemable Noncontrolling Interest Equity Fair Value [Abstract]
Noncontrolling interest, beginning balance			$ 19,373
Redemption of units			(203)
Net income attributable to noncontrolling interest in the Operating Partnership	$ 183	$ 77	344	$ 172
Distributions			(435)
Adjustment to redemption value			1,565
Noncontrolling interest, ending balance	$ 20,644		$ 20,644

Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

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- Definition

Amount after tax of income (loss) attributable to redeemable noncontrolling partner in an operating partnership.

+ References

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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- References

No definition available.

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