Fair Value of Financial Instruments - Carrying Amounts and Fair Values of Financial Instruments Measured based on Level Two Inputs (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Carrying Value
Fair Value of Financial Instruments
Indebtedness	$ 488,609	$ 522,180
Carrying Value \| Interest rate swaps
Fair Value of Financial Instruments
Interest rate liabilities	447	829
Interest rate assets	10	0
Carrying Value \| Interest rate caps
Fair Value of Financial Instruments
Interest rate assets	707	259
Fair Value \| Level 2
Fair Value of Financial Instruments
Indebtedness	491,026	527,414
Fair Value \| Level 2 \| Interest rate swaps
Fair Value of Financial Instruments
Interest rate liabilities	447	829
Interest rate assets	10	0
Fair Value \| Level 2 \| Interest rate caps
Fair Value of Financial Instruments
Interest rate assets	$ 707	$ 259

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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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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