Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation - Additional Information (Detail)

v2.4.0.8
Basis of Presentation - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2013
Basis Of Presentation [Line Items]    
Payments received related to break-up fee and termination of certain purchase and sale agreement $ 9.2 $ 9.2
Third-party expenses related to the cancelled transaction $ 0.1 $ 0.1