Stock Transactions and Unit Redemptions - Schedule of Changes in Carrying Amount of Redeemable Partnership Interest (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Equity [Abstract]
Balance at beginning of period	$ 26,170	$ 21,096
Income allocation	5,288	6,779
Distributions of income	(1,677)	(2,843)
FPU redemptions	(905)	(1,101)
Issuance	0	2,239
Other	19	0
Balance at end of period	$ 28,895	$ 26,170

No definition available.

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- Definition

Value of accretion of temporary equity during the period due to unpaid dividends.

+ References

No definition available.

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- Definition

Value of accretion of temporary equity to its redemption value during the period.

+ References

No definition available.

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- Definition

Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.27(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The portion of net income or loss attributable to temporary equity interest.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in temporary equity from changes classified as other.

+ References

No definition available.

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- Definition

Value of new stock classified as temporary equity issued during the period.

+ References

No definition available.

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