Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Summary of Company's Current Debt Portfolio (Parenthetical) (Detail)

v2.4.0.8
Long-Term Debt - Summary of Company's Current Debt Portfolio (Parenthetical) (Detail)
 9 Months Ended 12 Months Ended
Sep. 30, 2013
Dec. 31, 2012
Jul. 30, 2013
9.125% Senior Notes, due April 2018 [Member]
      
Debt Instrument [Line Items]      
Debt instrument maturity date April 2018 April 2018  
Debt instrument fixed interest rate 9.125% 9.125%  
7.50% Senior Notes, due August 2020 [Member]
      
Debt Instrument [Line Items]      
Debt instrument maturity date August 2020 August 2020  
Debt instrument fixed interest rate 7.50% 7.50% 7.50%