Management Internalization - Additional Information (Detail) - USD ($)		12 Months Ended
Dec. 20, 2016	Dec. 31, 2016
Business Acquisition [Line Items]
Management internalization expense	$ 2,119,000	$ 44,976,000
Management Internalization
Business Acquisition [Line Items]
Other assets	25,000
Liabilities recognized	0
Present value of unfavorable difference between actual and potential payment based on agreements.	43,000,000
Net assets acquired	143,000
Consideration transferred	43,000,000
Business acquisition loss recognized amount	42,857,000
Management Internalization \| Customer List
Business Acquisition [Line Items]
Intangible assets	$ 118,000

Management internalization expense.

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Present value of unfavorable difference between actual and potential payment based on agreements.

+ References

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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.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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-Publisher FASB
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The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The net gains or losses recognized for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

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