Fair Value Measurements - Schedule of Balance Sheet Location and Fair Value of Company's Interest Rate Swaps (Detail) - Derivatives Designated as Hedging Instruments [Member] $ in Thousands	Sep. 30, 2017 USD ($)
Other Non current Assets [Member]
Derivatives Fair Value [Line Items]
Interest rate swaps	$ 6,771
Other Current Liabilities [Member]
Derivatives Fair Value [Line Items]
Interest rate swaps	$ (2,769)

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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