Long-Lived Assets - Schedule of Accretion Discount Rates on Interest Method (Detail)	1 Months Ended			3 Months Ended	6 Months Ended	9 Months Ended	1 Months Ended
	Sep. 30, 2013 Incremental Estimates [Member]	Sep. 30, 2012 Incremental Estimates [Member]	Sep. 30, 2011 Incremental Estimates [Member]	Mar. 31, 2011 Additions [Member]	Sep. 30, 2011 Additions [Member]	Sep. 30, 2012 Additions [Member]	Dec. 31, 2013 Additions [Member] Incremental Estimates [Member]	Dec. 31, 2012 Additions [Member] Incremental Estimates [Member]	Dec. 31, 2011 Additions [Member] Incremental Estimates [Member]
Long Term Debt Percentage Interest Rate Type [Line Items]
Accretion discount rates on interest method	10.60%	12.14%	12.17%	12.46%	11.50%	10.77%	10.48%	10.60%	10.77%