Commitments and Contingencies - Additional Information (Detail) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2001
Commitments and Contingencies [Line Items]
Acquired interest percentage		33.80%
Minimum
Commitments and Contingencies [Line Items]
Lease term, (years)	1 year
Maximum
Commitments and Contingencies [Line Items]
Lease term, (years)	20 years
Contingent Promissory Note
Commitments and Contingencies [Line Items]
Principal amount of contingent promissory note		$ 40,000,000
Promissory note term (years)		20 years
Contingent promissory note, maximum amount including interest		$ 96,000,000

Commitments And Contingencies [Line Items]

No definition available.

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- Definition

Long Term Debt Contingent Payment Of Principal Or Interest Principal Including Unpaid Interest

+ References

No definition available.

+ Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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