Subsequent Events - Additional Information (Detail) (Subsequent Event, Third Amendment, USD $) In Millions, unless otherwise specified	1 Months Ended
Dec. 11, 2013
Subsequent Event \| Third Amendment
Subsequent Event [Line Items]
Syndicated line of credit, minimum capacity	$ 650.0
Syndicated line of credit, increased capacity	$ 800.0
Syndicated line of credit facility, expiration date	Dec. 11, 2018
Decrease in percentage of commitment fee on the unused portion of the Facility	0.025%

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant