Basis of Presentation and New Accounting Pronouncements - Additional Information (Detail)	Sep. 30, 2015
Variable Interest Entity, Primary Beneficiary [Member]
Basis Of Presentation [Line Items]
Direct ownership percentage in joint venture	75.00%
Unnamed Corporate Joint Venture [Member]
Basis Of Presentation [Line Items]
Equity method ownership percentage in joint venture	37.50%

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant